[ { "id": "https://thesis.library.caltech.edu/id/eprint/4010", "eprint_id": 4010, "rev_number": 12, "documents": [ { "id": "/id/document/6678", "doc_id": 6678, "rev_number": 3, "files": [ { "id": "/id/file/40373", "fileid": 40373, "datasetid": "document", "objectid": 6678, "filename": "Tsaur_by_1980.pdf", "mime_type": "application/pdf", "filesize": 8394565, "mtime": "2012-12-26 03:04:43", "url": "/4010/1/Tsaur_by_1980.pdf" } ], "eprint_id": 4010, "pos": 1, "mime_type": "application/pdf", "format": "application/pdf", "format_desc": "Tsaur_by_1980.pdf", "language": "en", "security": "public", "license": "other", "main": "Tsaur_by_1980.pdf", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "final", "relation": { "items": [ { "type": "http://eprints.org/relation/hasVolatileVersion", "uri": "/id/document/23212" }, { "type": "http://eprints.org/relation/haspreviewThumbnailVersion", "uri": "/id/document/23212" }, { "type": "http://eprints.org/relation/hasVersion", "uri": "/id/document/23212" } ] } }, { "id": "/id/document/23212", "doc_id": 23212, "rev_number": 3, "files": [ { "id": "/id/file/40371", "fileid": 40371, "datasetid": "document", "objectid": 23212, "filename": "preview.png", "mime_type": "image/png", "hash": "54863987a4dcfd6dc92da3a7e8309af6", "hash_type": "MD5", "filesize": 8998, "mtime": "2012-12-26 03:04:43", "url": "/4010/2/preview.png" } ], "eprint_id": 4010, "pos": 2, "placement": 2, "mime_type": "image/png", "format": "image/png", "language": "en", "security": "public", "license": "other", "main": "preview.png", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "relation": { "items": [ { "type": "http://eprints.org/relation/isVolatileVersionOf", "uri": "/id/document/6678" }, { "type": "http://eprints.org/relation/ispreviewThumbnailVersionOf", "uri": "/id/document/6678" }, { "type": "http://eprints.org/relation/isVersionOf", "uri": "/id/document/6678" } ] } } ], "eprint_status": "archive", "userid": 2, "dir": "disk0/00/00/40/10", "datestamp": "2006-10-19", "lastmod": "2021-04-16 22:24:26", "status_changed": "2009-09-25 03:09:45", "type": "thesis", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tsaur-Bor-Yeu", "name": { "family": "Tsaur", "given": "Bor-Yeu" }, "show_email": "NO" } ] }, "title": "Ion-beam-induced modifications of thin film structures and formation of metastable phases", "ispublished": "unpub", "full_text_status": "public", "abstract": "The influences of energetic ion bombardment on the composition and structure of thin film materials and the utilization of ion-beam-mixing techniques to produce compounds and alloys are reported in this thesis.\r\n\r\nMotivated by recent experimental observations that ion bombardment can induce alteration of atomic distributions in composite materials, a systematic study of ion-induced modification of interface profile and structure has been carried out. By bombarding through a thin transition-metal film deposited on a Si substrate, significant atomic mixing was observed near the metal-Si interface at dose levels of ~10(15)cm(-2). The atomic mixing led to the formation of well-defined silicide phases which are identical to those obtained by normal thermal treatment. A macroscopic model based on collision-cascade mixing and radiation-enhanced diffusion mechanisms was proposed to account for the ion-induced interface reaction. The mixing process and its products were found to be strongly influenced by the implantation conditions such as ion energy, mass, fluence and sample temperature, as well as by the intrinsic properties of target material such as thermal diffusivity and radiation stability. Ion-beam-mixing at higher ion doses (~10(16)cm(-2)) led to the formation of more Si-rich phases or disordered metal-Si layers which are difficult to form or, in some cases, inaccessible by normal thermal process. The phenomenon of ion-induced silicide formation is similar to that observed in thermal annealing except that the radiation stability of phase structure is important in determining whether a silicide phase is formed or a disordered metal-Si mixture is formed. (Chapter 2)\r\n\r\nThe ion-beam-mixing process was then utilized to investigate the production of nonequilibrium (or metastable) phases. A metastable silicide phase of a stoichiometry Pt2Si3 has been obtained by heat treating a Si-rich amorphous Pt-Si alloy layer produced by ion-beam-mixing of thin PtSi (or Pt) films on Si. The Pt2Si3 phase is absent in the equilibrium phase diagram of Pt-Si and has not been reported before. X-ray diffraction analysis established the crystal structure of Pt2Si3 to be hexagonal with lattice parameters a = 3.841 \u00c5, c = 11.924 \u00c5 and with 10 atoms per unit cell. The metastable phase was found to exhibit a superconducting transition onset at about 4.2K and to become completely superconductive at temperature below 3.6K. For the first time, a compound of this structure was observed to be a superconductive material. The transformation behavior of the ion-induced amorphous Pt2Si3 alloy has been studied by using resistivity measurements. The amorphous to metastable crystalline transformation occurred at ~400\u00b0C as indicated by an abrupt decrease of resistivity. The metastable phase then gradually decomposed into an equilibrium PtSi and Si mixture at temperatures above 550\u00b0C. The kinetics of amorphous to crystalline transformation have been determined by isothermal treatment over the temperature interval 376-392\u00b0C. The results were interpreted in terms of a classical nucleation and growth mechanism with a t4 (time) dependence and an apparent activation enthalpy of 4.69 eV (108 kcal/mole). The microstructures of the alloys at various stages of transformation were studied by transmission electron microscopy and diffraction. The results were found to correlate well to the phase transformation behavior observed by resistivity measurements. (Chapters 3 and 4)\r\n\r\nTo further investigate the production of metastable phases by ion-beam mixing, experiments have been performed in the simple eutectic system of Au-Si. An amorphous alloy with a uniform composition Au-28 at .% Si (~Au5Si2) was formed by bombarding through a thin Au film on Si, a result distinctly different from that obtained in normal thermal treatment. Upon thermal annealing, the amorphous phase transforms into a metastable crystalline phase at ~100\u00b0C, which then gradually decomposes into an equilibrium Au and Si mixture at higher temperatures. The present observations were compared with those obtained previously by rapid quenching techniques. The comparison of metastable phase formation in the Pt-Si and Au-Si systems revealed a correlation between the existence of metastable phases and eutectic compositions, as well as the importance of sample temperature during implantation for direct observation of metastable phases. (Chapter 5)\r\n\r\nAs an extension of compound formation by ion-beam-mixing of a thin layer on a thick substrate, we investigated the mixing of thin deposited layers as a scheme for producing compounds or alloys of desirable compositions. Multiple-layered samples consisting of thin alternate layers of two elements were prepared by sequential vacuum deposition of the two components onto an inert substrate such as Si02 or Al2O3. The relative thicknesses of the individual layers were adjusted such that the average film composition was equal to a fixed, predetermined value. Ion bombardment was then performed to homogenize the layers on an atomic scale. Formation of supersaturated Ag-Cu and Au-Co solid solutions over a wide range of composition has been achieved. Extensions of alloy solubility and formation of amorphous phases have been obtained in the almost completely immiscible systems of Ag-Ni and Cu-Ta, respectively. The present scheme may promise to be a new technique for producing metastable phases which are difficult to form or unattainable by conventional rapid quenching techniques. (Chapter 6)\r\n\r\nFinally, we consider the possibility of using ion-beam-mixing techniques as an alternative approach to direct high dose implantation for material surface modification. Comparison between ion-beam-mixing and high dose implantation is made to demonstrate the \"effectiveness\" of ion-beam mixing in incorporating Au or Ag in single crystal Cu substrates. A simple diffusion model for the evolution of ion-beam-mixing of a thin surface layer on a thick substrate was then proposed. The model predicts the influence of implantation conditions and material properties on the redistribution of the thin surface layers. From a practical point of view, the technique of introducing foreign species by ion-beam-mixing process exhibits many attractive advantages over direct implantation because of significantly lower ion doses required and the ability to use simple ion sources. (Chapter 7).", "date": "1980", "date_type": "degree", "id_number": "CaltechETD:etd-10102006-094500", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechETD:etd-10102006-094500", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "collection": "CaltechTHESIS", "deposited_by": "Imported from ETD-db", "deposited_on": "2006-10-19", "doi": "10.7907/2v82-tm86", "divisions": { "items": [ "div_eng" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "advisor" }, { "id": "Nicolet-M", "name": { "family": "Nicolet", "given": "Marc-Aurele" }, "role": "advisor" } ] }, "thesis_committee": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "chair" }, { "id": "Nicolet-M", "name": { "family": "Nicolet", "given": "Marc-Aurele" }, "role": "member" }, { "id": "Vreeland-T", "name": { "family": "Vreeland", "given": "Thad" }, "role": "member" }, { "id": "Johnson-W-L", "name": { "family": "Johnson", "given": "William Lewis" }, "role": "member" } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_submitted_date": "2006-10-10", "thesis_defense_date": "1980-04-21", "thesis_approved_date": "2006-10-19", "review_status": "approved", "option_major": { "items": [ "eleceng" ] }, "copyright_statement": "I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive\nlicense to archive and make accessible, under the conditions specified below,\nmy thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1980", "author_list": "Tsaur, Bor-Yeu", "advisor_list": "Mayer, James Walter and Nicolet, Marc-Aurele", "comittee_list": "Mayer, James Walter; Nicolet, Marc-Aurele; et el." }, { "id": "https://thesis.library.caltech.edu/id/eprint/4045", "eprint_id": 4045, "rev_number": 12, "documents": [ { "id": "/id/document/6719", "doc_id": 6719, "rev_number": 3, "files": [ { "id": "/id/file/40665", "fileid": 40665, "datasetid": "document", "objectid": 6719, "filename": "Cheung_wn_1980.pdf", "mime_type": "application/pdf", "filesize": 8911149, "mtime": "2012-12-26 03:05:00", "url": "/4045/1/Cheung_wn_1980.pdf" } ], "eprint_id": 4045, "pos": 1, "mime_type": "application/pdf", "format": "application/pdf", "format_desc": "Cheung_wn_1980.pdf", "language": "en", "security": "public", "license": "other", "main": "Cheung_wn_1980.pdf", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "final", "relation": { "items": [ { "type": "http://eprints.org/relation/hasVolatileVersion", "uri": "/id/document/23253" }, { "type": "http://eprints.org/relation/haspreviewThumbnailVersion", "uri": "/id/document/23253" }, { "type": "http://eprints.org/relation/hasVersion", "uri": "/id/document/23253" } ] } }, { "id": "/id/document/23253", "doc_id": 23253, "rev_number": 3, "files": [ { "id": "/id/file/40663", "fileid": 40663, "datasetid": "document", "objectid": 23253, "filename": "preview.png", "mime_type": "image/png", "hash": "db33c9e52a5f045f4fa8f595d1c33ce0", "hash_type": "MD5", "filesize": 10437, "mtime": "2012-12-26 03:05:00", "url": "/4045/2/preview.png" } ], "eprint_id": 4045, "pos": 2, "placement": 2, "mime_type": "image/png", "format": "image/png", "language": "en", "security": "public", "license": "other", "main": "preview.png", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "relation": { "items": [ { "type": "http://eprints.org/relation/isVolatileVersionOf", "uri": "/id/document/6719" }, { "type": "http://eprints.org/relation/ispreviewThumbnailVersionOf", "uri": "/id/document/6719" }, { "type": "http://eprints.org/relation/isVersionOf", "uri": "/id/document/6719" } ] } } ], "eprint_status": "archive", "userid": 2, "dir": "disk0/00/00/40/45", "datestamp": "2006-10-27", "lastmod": "2021-04-16 23:20:27", "status_changed": "2009-09-25 03:10:33", "type": "thesis", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheung-Woontong-Nathan", "name": { "family": "Cheung", "given": "Woontong Nathan" }, "show_email": "NO" } ] }, "title": "I. Channeling studies of silicon interfaces. II. Diffusion barrier properties of titanium nitride", "ispublished": "unpub", "full_text_status": "public", "abstract": "NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.\r\n\r\nPart I\r\n\r\nThe channeling effect of MeV ions in crystalline materials has been applied to study the interfaces of metals, silicides and oxides with single-crystal Si substrates. The study was facilitated by the development of thin (1500-5000\u00c5) Si crystals which enabled channeled ions to probe the interfacial region without first traversing the metal or silicide layers. These investigations revealed that a reaction occurs between the silicon and as-deposited metal layers. For the Ni-Si system, about three monolayers of Ni penetrate into Si and occupy interstitial sites. An interfacial layer is also found between silicides and Si. In contrast, an abrupt interface is found between SiO2 and Si.\r\n\r\nWith conventional channeling techniques, the ion beam traverses first the overlayer and then the Si substrate. A Si peak is observed in the energy spectrum and the area of the peak can be converted to Si atoms/cm(2) from known Rutherford scattering cross-sections. The Si peak corresponds to the first few monolayers of crystalline Si (the \"surface peak\"), the non-registered Si at the interface and the amount of Si in the silicide or oxide. From recent theoretical and experimental studies on surfaces, the surface peak contribution can be accurately predicted.\r\n\r\nUsing different overlayer thicknesses, the stoichiometry of silicides and oxides and the interfacial disordered Si can be determined. In the case of metal-Si interfaces, the interfacial reactivity can be monitored by measuring the amount of non-registered Si at the interface. However, the conventional channeling technique is applicable only when the multiple scattering of the incident beam by the overlayer is small (i.e. thin overlayers and low atomic number elements).\r\n\r\nAdditional information on the nature of the interfacial disordered Si can be obtained by the thin-crystal channeling technique which involves the use of thin ([...]), self-supporting Si crystals. With the ions first traversing the Si thin crystal along a channeling direction, the channeled ions are steered away from the atomic rows. At the interfacial region, the channeled ions only interact with the interfacial Si atoms which are displaced [...] laterally from the atomic rows. There is no contribution from the first few crystalline Si layers to the measured Si peak; as there is in the case of conventional channeling. The combination of both conventional and thin-crystal channeling techniques provides further information about the interfacial disorder because of the different sensitivities of the two techniques to lateral displacements. Thin-crystal channeling has also been used to locate the relative position of foreign atoms with respect to the Si lattice near the interfacial region. This technique requires angular scan experiments along various axial and planar channeling directions.\r\n\r\nFor metal-Si interfaces, channeling results show that an interfacial reaction is initiated at room temperature with as-deposited metal layers (Ni, Pd, Cr, V and Au); Ag is the only exception. With the Ni-Si system, the interfacial reaction can be greatly reduced by cooling the substrate to 170\u00b0K during Ni deposition and ion beam analysis. The temperature dependence of the interfacial reactivity emphasizes the kinetic nature of the metal-Si interfaces and the importance of interfacial studies at low temperatures for meaningful comparison with abrupt metal-semiconductor interface models. The amount of disordered interfacial Si is observed to be high for metals which are dominant diffusion species in silicide formation (e.g. Ni and Pd). A lattice location experiment on the Ni-Si interface shows that ~3 monolayers of Ni atoms are situated interstitially at the tetrahedral sites of crystalline Si. This observation supports the interstitial diffusion model which was proposed by Tu to explain the low-temperature formation of silicides.\r\n\r\nInterfaces between Si and Pd2Si, Ni2Si, NiSi or NiSi2 have also been investigated by thin-crystal channeling. The Ni2Si-Si interface shows ~4x10(16) atoms/cm(2) of excess Si above an \"ideal\" Ni2Si-Si interface. The other silicide-Si interfaces all show disordered interfacial Si of <8x10(15) atoms/cm(2). The amount of interfacial disorder correlates with the transformation temperature for the next stable silicide phase. For example, the Ni2Si phase (which exhibits the highest interfacial disorder) transforms to NiSi at ~350\u00b0C. In contrast, the other silicide phases, Pd2Si and NiSi, require a much higher transformation temperature (~700\u00b0C).\r\n\r\nThe SiO2-Si interface has been studied by both conventional and thin-crystal channeling. The results show that thermally grown oxides on (110)Si are stoichiometric SiO2 at least down to a thickness of 4\u00c5. By comparing the channeling data with predictions based on a various number of reconstructed Si layers, an abrupt SiO2-Si interface is deduced with 2 monolayers of the Si single crystal being reconstructed at the interface.\r\n\r\nPart II\r\n\r\nThis part of the thesis is concerned with the deposition and evaluation of titanium nitride (TiN) layers as diffusion barriers in contact metallization on Si devices. The application of TiN to Si solar cell contacts (i.e., the TiN-Ti-Ag metallization scheme) has been demonstrated to withstand a 600\u00b0C, 10 min anneal without degrading the cell's performance.\r\n\r\nTitanium nitride films have been prepared by reactive sputtering of Ti in a nitrogen plasma. The nitride films are identified by TEM and X-ray diffraction to have the NaCl structure with a lattice parameter of 4.24\u00b10.02\u00c5. Electrical properties and atomic composition of the films have been studied as a function of sputtering RF power (500-1500 W) and nitrogen pressure (3-100 mT). Backscattering analysis shows that the films have a composition close to stoichiometric TiN but with a slight tendency for higher nitrogen content. Oxygen is the major contaminant in the nitride films. The oxygen content strongly depends on the sputtering parameters and a high oxygen content corresponds to high electrical resistivity of the TiN films. The lowest resistivity (~170[...]-cm) is obtained by sputtering with high RF power and low nitrogen pressure.\r\n\r\nThe effectiveness of titanium nitride films as a diffusion barrier between various metals and single-crystal Si substrate or Ti on single-crystal Si substrate is investigated by backscattering spectrometry, SEM and EDAX. The temperature range of interest is from 400\u00b0C to 700\u00b0C. Various metals of high electrical conductivity such as Au, Ag, Al, Cu and Pd are used as the top metal layer. By interposing a thin layer of TiN ([...] 1000 \u00c5) between the metal and substrate, the failure temperature (i.e., the temperature at which metal-substrate interdiffusion becomes significant) can be greatly increased. The failure temperature of the TiN layers as a diffusion barrier is related to the metal-silicon eutectic temperature. SEM studies show that the interdiffused layer is laterally non-uniform and is initiated at isolated spots across the sample's surface. It is believed that grain boundaries or pinholes in the TiN films are the weak links in the diffusion barrier properties of TiN.\r\n\r\nAs an application for high-temperature diffusion barriers, the Ag-Ti-TiN metallization scheme has been tested on shallow-junction (~2000A) Si solar cells. The conventional Ti-Pd-Ag metallization scheme has been shown to fail after a 600\u00b0C, 10 min anneal which is required for a glass encapsulation process. With the TiN-Ti-Ag scheme, no degradation of cell performance can be observed after the 600\u00b0C, 10 min anneal if the TiN layer is [...]1500\u00c5.", "date": "1980", "date_type": "degree", "id_number": "CaltechETD:etd-10122006-090333", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechETD:etd-10122006-090333", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "collection": "CaltechTHESIS", "deposited_by": "Imported from ETD-db", "deposited_on": "2006-10-27", "doi": "10.7907/e47n-cg57", "divisions": { "items": [ "div_eng" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "advisor" }, { "id": "Nicolet-M", "name": { "family": "Nicolet", "given": "Marc-Aurele" }, "role": "advisor" } ] }, "thesis_committee": { "items": [ { "name": { "family": "Unknown", "given": "Unknown" } } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_submitted_date": "2006-10-12", "thesis_defense_date": "1980-05-12", "thesis_approved_date": "2006-10-27", "review_status": "approved", "option_major": { "items": [ "eleceng" ] }, "copyright_statement": "I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive\nlicense to archive and make accessible, under the conditions specified below,\nmy thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1980", "author_list": "Cheung, Woontong Nathan", "advisor_list": "Mayer, James Walter and Nicolet, Marc-Aurele", "comittee_list": "Unknown, Unknown" }, { "id": "https://thesis.library.caltech.edu/id/eprint/8575", "eprint_id": 8575, "rev_number": 20, "documents": [ { "id": "/id/document/51051", "doc_id": 51051, "rev_number": 2, "files": [ { "id": "/id/file/147802", "fileid": 147802, "datasetid": "document", "objectid": 51051, "filename": "Olowolafe_jo_1977.pdf", "mime_type": "application/pdf", "hash": "3b4049c4bbf85a7aff7f6354f2a9c614", "hash_type": "MD5", "filesize": 15634652, "mtime": "2014-07-21 21:33:56", "url": "/8575/1/Olowolafe_jo_1977.pdf" } ], "eprint_id": 8575, "pos": 1, "placement": 1, "mime_type": "application/pdf", "format": "application/pdf", "language": "en", "security": "public", "license": 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"/id/document/51051" }, { "type": "http://eprints.org/relation/isIndexCodesVersionOf", "uri": "/id/document/51051" } ] } } ], "eprint_status": "archive", "userid": 87, "dir": "disk0/00/00/85/75", "datestamp": "2014-07-23 16:57:50", "lastmod": "2021-01-25 22:16:38", "status_changed": "2014-07-23 16:57:50", "type": "thesis", "metadata_visibility": "show", "creators": { "items": [ { "id": "Olowolafe-Johnson-Olufemi", "name": { "family": "Olowolafe", "given": "Johnson Olufemi" } } ] }, "title": "Silicide formation and the interaction of metals with polycrystalline Si", "ispublished": "unpub", "full_text_status": "public", "keywords": "Applied Physics ", "note": "Part of this thesis has been previously published\r\nunder the following titles:\r\n.. Iron Silicide Thin Film Formation at Low Temperatures,\"\r\nThin Solid Films~, 415 (1975), s.s. Lau, J.S.Y.\r\nFeng, J.O. Olowolafe and M-A. Nicolet .\r\n.. Interaction of Metal Layers with Polycrystalline Si, ..\r\nJ. Appl. Phys. !I, 1278 (1976), K. Nakamura,\r\nJ.O. Olowolafe, S.S. Lau, M-A. Nicolet and\r\nJ.H. Mayer.\r\n\"Influence of the Si Substrates on the Formation of Ni\r\nSilicides,\" Thin Solid Films ~, 143 (1976).\r\nJ.O. Olowolafe, M-A. Nicolet and J.W. Mayer .\r\n\"Formation Kinetics of CrSj 2 Films on Si Substrates with\r\nand Without Interposed Pd2si Layer,\" J. Appl.\r\nPhys. !l\u2022 5182 (1976), J.O. Olowolafe, M-A.\r\nNicolet and J.W. Mayer.\r\n\"Chromium Thin Films as a Barrier to the Interaction of\r\nPd2Si withAl,\" Solid-State Electron. (in press),\r\nJ.O. Olowolafe, M-A. Nicolet and J.W. Mayer.\r\n\"Analysis of Semiconductor Structures by Nuclear and Electrical\r\nTechniques,\" (Section D), Air Force\r\nCambridge Research Laboratories Scientific\r\nReport No. 2 (1975).\r\n\"Radioactive Silicon Tracer Studies of the Formation of\r\nCrsi2 on Pd2Si and PtSi,\" (to be published),\r\nR. Pretorius, J.O. Olowolafe anu J.W. Mayer.", "abstract": "
The main factors affecting solid-phase Si-metal interactions are reported in this work. The influence of the orientation of the Si substrates and the presence of impurities in metal films and at the Si-metal interface on the formation of nickel and chromium silicides have been demonstrated. We have observed that the formation and kinetic rate of growth of nickel silicides is strongly dependent on the orientation and crystallinity of the Si substrates; a fact which, up to date, has never been seriously investigated in silicide formation. Impurity contaminations in the Cr film and at the Si-Cr interface are the most dominant influencing factors in the formation and kinetic rate of growth of CrSi2. The potentiality and use of silicides as a diffusion barrier in metallization on silicon devices were also investigated.
\r\n\r\nTwo phases, Ni2Si and NiSi, form simultaneously in two distinct sublayers in the reaction of Ni with amorphous Si, while only the former phase was observed on other substrates. On (111) oriented Si substrates the growth rate is about 2 to 3 times less than that on <100> or polycrystalline Si. Transmission electron micrographs establish-\u00b7that silicide layers grown on different substrates have different microcrystalline structures. The concept of grain-boundary diffusion is speculated to be an important factor in silicide formation.
\r\n\r\nThe composition and kinetic rate of CrSi2 formation are not influenced by the underlying Si substrate. While the orientation of the Si substrate does not affect the formation of CrSi2 , the purity of the Cr film and the state of Si-Cr interface become the predominant factors in the reaction process. With an interposed layer of Pd2Si between the Cr film and the Si substrate, CrSi2 starts to form at a much lower temperature (400\u00b0C) relative to the Si-Cr system. However, the growth rate of CrSi2 is observed to be independent of the thickness of the Pd2Si layer. For both Si-Cr and Si-Pd2Si-Cr samples, the growth rate is linear with time with an activation energy of 1.7 \u00b1 0.1 ev.
\r\n \r\nA tracer technique using radioactive 31Si (T1/2 = 2.26 h) was used to study the formation of CrSi2 on Pd2Si. It is established from this experiment that the growth of CrSi2 takes place partly by transport of Si directly from the Si substrate and partly by breaking Pd2Si bonds, making free Si atoms available for the growth process.
\r\n\r\nThe role of CrSi2 in Pd-Al metallization on Si was studied. It is established that a thin CrSi2 layer can be used as a diffusion barrier to prevent Al from interacting with Pd2Si in the Pd-Al metallization on Si.
\r\n\r\nAs a generalization of what has been observed for polycrystalline-Si-Al interaction, the reactions between polycrystalline Si (poly Si) and other metals were studied. The metals investigated include Ni, Cr, Pd, Ag and Au. For Ni, Cr and Pd, annealing results in silicide formation, at temperatures similar to those observed on single crystal Si substrates. For Al, Ag and Au, which form simple eutectics with Si annealing results in erosion of the poly Si layer and growth of Si crystallites in the metal films.
\r\n\r\nBackscattering spectrometry with 2.0 and 2.3 MeV 4He ions was the main analytical tool used in all our investigations. Other experimental techniques include the Read camera glancing angle x-ray diffraction, scanning electron, optical and transmission electron microscopy. Details of these analytical techniques are given in Chapter II.
\r\n", "date": "1977", "date_type": "degree", "id_number": "CaltechTHESIS:07212014-113955709", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechTHESIS:07212014-113955709", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "collection": "CaltechTHESIS", "reviewer": "Kathy Johnson", "deposited_by": "Benjamin Perez", "deposited_on": "2014-07-23 16:57:50", "doi": "10.7907/JZBN-0V57", "divisions": { "items": [ "div_eng" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "advisor" } ] }, "thesis_committee": { "items": [ { "name": { "family": "Unknown", "given": "Unknown" } } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_defense_date": "1977-01-14", "review_status": "approved", "option_major": { "items": [ "appliedphys" ] }, "copyright_statement": "Author's Rights Authorization: I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted here is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive license to archive and make accessible, under the conditions specified under \"Thesis Availability\" in this submission, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation, or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1977", "author_list": "Olowolafe, Johnson Olufemi", "advisor_list": "Mayer, James Walter", "comittee_list": "Unknown, Unknown" }, { "id": "https://thesis.library.caltech.edu/id/eprint/8550", "eprint_id": 8550, "rev_number": 32, "documents": [ { "id": "/id/document/50880", "doc_id": 50880, "rev_number": 2, "files": [ { "id": "/id/file/147284", "fileid": 147284, "datasetid": "document", "objectid": 50880, "filename": "Harris_jm_1976.pdf", "mime_type": "application/pdf", "hash": "459f900759d866b2c96095c91976ad1d", "hash_type": "MD5", "filesize": 12049594, "mtime": "2014-07-17 18:00:06", "url": "/8550/7/Harris_jm_1976.pdf" } ], "eprint_id": 8550, "pos": 7, "placement": 7, "mime_type": "application/pdf", "format": "application/pdf", "language": "en", "security": "public", "license": "other", "main": 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"media_sample_stop": "0", "content": "final" }, { "id": "/id/document/129227", "doc_id": 129227, "rev_number": 1, "files": [ { "id": "/id/file/374663", "fileid": 374663, "datasetid": "document", "objectid": 129227, "filename": "indexcodes.txt", "mime_type": "text/plain", "hash": "0ac00dbbf7e2891c8f0cadc21d0a0114", "hash_type": "MD5", "filesize": 22378, "mtime": "2021-06-24 03:35:54", "url": "/8550/14/indexcodes.txt" } ], "eprint_id": 8550, "pos": 14, "placement": 14, "mime_type": "text/plain", "format": "other", "format_desc": "Generate index codes conversion from application/pdf to indexcodes", "language": "en", "security": "public", "license": "other", "main": "indexcodes.txt", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "relation": { "items": [ { "type": "http://eprints.org/relation/isVersionOf", "uri": "/id/document/50880" }, { "type": "http://eprints.org/relation/isVolatileVersionOf", "uri": "/id/document/50880" }, { "type": "http://eprints.org/relation/isIndexCodesVersionOf", "uri": "/id/document/50880" } ] } } ], "eprint_status": "archive", "userid": 87, "dir": "disk0/00/00/85/50", "datestamp": "2014-07-17 18:23:20", "lastmod": "2021-01-25 22:16:56", "status_changed": "2014-07-17 18:23:20", "type": "thesis", "metadata_visibility": "show", "creators": { "items": [ { "id": "Harris-Joe-Marion", "name": { "family": "Harris", "given": "Joe Marion" }, "show_email": "NO" } ] }, "title": "Part I. Energy Straggling of \u2074He below 2.0 MeV in Al, Ni, Au, and Pt. Part II. Studies of the Ti-W Metallization System on Si", "ispublished": "unpub", "full_text_status": "public", "keywords": "Applied Physics ", "abstract": "Part I.
\r\n\r\nIn recent years, backscattering spectrometry has become an important\r\ntool for the analysis of thin films. An inherent limitation,\r\nthough, is the loss of depth resolution due to energy straggling of\r\nthe beam. To investigate this, energy straggling of 4He has been\r\nmeasured in thin films of Ni, Al, Au and Pt. Straggling is roughly\r\nproportional to square root of thickness, appears to have a slight\r\nenergy dependence and generally decreases with decreasing atomic\r\nnumber of the adsorber. The results are compared with predictions\r\nof theory and with previous measurements. While Ni measurements are\r\nin fair agreement with Bohr's theory, Al measurements are 30% above\r\nand Au measurements are 40% below predicted values. The Au and Pt\r\nmeasurements give straggling values which are close to one another.
\r\n\r\nPart II.
\r\n\r\nMeV backscattering spectrometry and X-ray diffraction are used to\r\ninvestigate the behavior of sputter-deposited Ti-W mixed films on Si\r\nsubstrates. During vacuum anneals at temperatures near 700\u00b0C for several\r\nhours, the metallization layer reacts with the substrate. Backscattering\r\nanalysis shows that the resulting compound layer is uniform in composition\r\nand contains Ti, Wand Si. The Ti:W ratio in the compound corresponds\r\nto that of the deposited metal film. X-ray analyses with\r\nReed and Guinier cameras reveal the presence of the ternary TixW(1-x)Si2\r\ncompound. Its composition is unaffected by oxygen contamination during\r\nannealing, but the reaction rate is affected. The rate measured on\r\nsamples with about 15% oxygen contamination after annealing is linear, of\r\nthe order of 0.5 \u00c5 per second at 725\u00b0C, and depends on the crystallographic\r\norientation of the substrate and the dc bias during sputter-deposition\r\nof the Ti-W film.
\r\n\r\nAu layers of about 1000 \u00c5 thickness were deposited onto unreacted\r\nTi-W films on Si. When annealed at 400\u00b0C these samples\r\nunderwent a color change,and SEM micrographs of the samples showed\r\nthat an intricate pattern of fissures which were typically 3\u00b5m wide\r\nhad evolved. Analysis by electron microprobe revealed that Au had\r\nsegregated preferentially into the fissures. This result suggests\r\nthat Ti-W is not a barrier to Au-Si intermixing at 400\u00b0C.
", "date": "1976", "date_type": "degree", "id_number": "CaltechTHESIS:07172014-102340032", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechTHESIS:07172014-102340032", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "collection": "CaltechTHESIS", "reviewer": "Tony Diaz", "deposited_by": "Benjamin Perez", "deposited_on": "2014-07-17 18:23:20", "doi": "10.7907/C4FY-ZX66", "alt_title": { "items": [ "Part I. Energy Straggling of ^4He below 2.0 MeV in Al, Ni, Au, and Pt. Part II. Studies of the Ti-W Metallization System on Si", "Part I. Energy Straggling of 4He below 2.0 MeV in Al, Ni, Au, and Pt. Part II. Studies of the Ti-W Metallization System on Si", "Energy Straggling of 4He below 2.0 MeV in Al, Ni, Au, and Pt", "Energy Straggling of \u2074He below 2.0 MeV in Al, Ni, Au, and Pt", "Studies of the Ti-W Metallization System on Si" ] }, "divisions": { "items": [ "div_eng" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Nicolet-M", "name": { "family": "Nicolet", "given": "Marc-Aurele" }, "role": "advisor" }, { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "co-advisor" } ] }, "thesis_committee": { "items": [ { "name": { "family": "Unknown", "given": "Unknown" } } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_defense_date": "1975-07-16", "review_status": "approved", "option_major": { "items": [ "appliedphys" ] }, "copyright_statement": "Author's Rights Authorization: I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted here is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive license to archive and make accessible, under the conditions specified under \"Thesis Availability\" in this submission, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation, or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1976", "author_list": "Harris, Joe Marion", "advisor_list": "Nicolet, Marc-Aurele and Mayer, James Walter", "comittee_list": "Unknown, Unknown" }, { "id": "https://thesis.library.caltech.edu/id/eprint/14392", "eprint_id": 14392, "rev_number": 18, "documents": [ { "id": "/id/document/135073", "doc_id": 135073, "rev_number": 2, "files": [ { "id": "/id/file/384135", "fileid": 384135, "datasetid": "document", "objectid": 135073, "filename": "Lee_T-WF_1975.pdf", "mime_type": "application/pdf", "hash": "eec3028514c0a9ebdccb1961472a5d85", "hash_type": "MD5", "filesize": 31889090, "mtime": "2021-10-13 20:44:53", "url": "/14392/1/Lee_T-WF_1975.pdf" } ], "eprint_id": 14392, "pos": 1, "placement": 1, "mime_type": "application/pdf", "format": "application/pdf", "language": "en", "security": "public", "license": "other", "main": "Lee_T-WF_1975.pdf", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "final" }, { "id": "/id/document/135074", "doc_id": 135074, "rev_number": 4, "files": [ { "id": "/id/file/384137", "fileid": 384137, "datasetid": "document", "objectid": 135074, "filename": "Lee_T-WF_1975.zip", "mime_type": "application/zip", "hash": "d707fa71a9cc0d6dde17078b65d52fd9", "hash_type": "MD5", "filesize": 126650349, "mtime": "2021-10-13 20:45:11", "url": "/14392/2/Lee_T-WF_1975.zip" } ], "eprint_id": 14392, "pos": 2, "placement": 2, "mime_type": "application/zip", "format": "application/zip", "format_desc": "TIFFs", "language": "en", "security": "internal", "license": "other", "main": "Lee_T-WF_1975.zip", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "archival" }, { "id": "/id/document/135196", "doc_id": 135196, "rev_number": 1, "files": [ { "id": "/id/file/384711", "fileid": 384711, "datasetid": "document", "objectid": 135196, "filename": "indexcodes.txt", "mime_type": "text/plain", "hash": "417336017145ea17d018d79ce0cee8a9", "hash_type": "MD5", "filesize": 15954, "mtime": "2021-10-20 16:40:11", "url": "/14392/3/indexcodes.txt" } ], "eprint_id": 14392, "pos": 3, "placement": 3, "mime_type": "text/plain", "format": "other", "format_desc": "Generate index codes conversion from application/pdf to indexcodes", "language": "en", "security": "public", "license": "other", "main": "indexcodes.txt", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "relation": { "items": [ { "type": "http://eprints.org/relation/isVersionOf", "uri": "/id/document/135073" }, { "type": "http://eprints.org/relation/isVolatileVersionOf", "uri": "/id/document/135073" }, { "type": "http://eprints.org/relation/isIndexCodesVersionOf", "uri": "/id/document/135073" } ] } } ], "eprint_status": "archive", "userid": 87, "dir": "disk0/00/01/43/92", "datestamp": "2021-10-13 22:28:42", "lastmod": "2021-10-13 22:29:27", "status_changed": "2021-10-13 22:28:42", "type": "thesis", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Tsu-wei-Frank", "name": { "family": "Lee", "given": "Tsu-wei Frank" }, "show_email": "NO" } ] }, "title": "Deep Levels and High Concentrations of Impurities in Silicon", "ispublished": "unpub", "full_text_status": "public", "keywords": "Electrical Engineering; Applied Mathematics", "abstract": "A study of the electronic levels associated with the divacancy in silicon is reported. The extended H\u00fcckel theory is shown to \r\nreproduce the band structure of silicon near the energy gap. The electronic levels of the divacancy are calculated by considering a periodic array of large unit cells each containing 62 atoms; a 64 atom perfect cell with 2 atoms removed to form the divacancy. The results are found to be in qualitative agreement with the results of EPR and infrared absorption measurements.
\r\n\r\nA theory of the variation of conduction electron density with the temperature for various impurity concentrations is presented. In addition to previously noted effects of conduction band edge lowering and screening of the impurity potential by the conduction electrons, the influence of a finite energy transfer integral and spatial fluctuation in the potential are included. The results show that for ND \u2272 1017 cm-3 silicon one must not view the activation as occurring between a single impurity level and a well defined conduction band edge, but must include the broadening of the impurity level and tailing of the conduction band density of states, Calculations for the shallow donors P, Sb, and As in Si are found to be in satisfactory agreement with experiment.
\r\n\r\nHall and sheet resistivity measurements as a function of temperature combined with layer removal have been used to study Si implanted with Te at energies up to 220 KeV. At low doses (\u2272 4 x 1012 cm-2), Te has a donor level with 140 meV activation energy. The activation energy decreases at higher Te doses and is approximately equal to zero for Te doses \u2273 1015 cm-2. At high dose levels, the number Ns of conduction electrons is more than an order of magnitude below the number of Te cm-2. High temperature anneal treatments followed by quenching did not produce a substantial increase in Ns suggesting that the formation of Te clusters was not responsible for the low value of Ns. Also channeling measurements indicated a high substitutional fraction. Based on differential Hall measurements on P-implanted samples, with and without Si pre-damage, we conclude that residual radiation damage is not a major factor. A theoretical calculation, which includes the effect of decrease of activation energy with increasing impurity concentrations, indicated that the number of conduction electrons could be much less than the number of implanted Te even though the apparent activation energy is almost zero. Although the results of theoretical calculation do not give quantitative agreement with the experimental results, they do confirm the changes in apparent activation energy with concentration.
", "date": "1975", "date_type": "degree", "id_number": "CaltechTHESIS:10122021-201307143", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechTHESIS:10122021-201307143", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "collection": "CaltechTHESIS", "reviewer": "Melissa Ray", "deposited_by": "Benjamin Perez", "deposited_on": "2021-10-13 22:28:42", "doi": "10.7907/j2rb-3s97", "divisions": { "items": [ "div_eng" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "advisor" }, { "id": "McGill-T-C", "name": { "family": "McGill", "given": "Thomas C." }, "role": "co-advisor" }, { "email": "man@caltech.edu", "id": "Nicolet-M", "name": { "family": "Nicolet", "given": "Marc-Aurele" }, "role": "co-advisor" } ] }, "thesis_committee": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "chair" }, { "id": "McGill-T-C", "name": { "family": "McGill", "given": "Thomas C." }, "role": "co-chair" }, { "email": "man@caltech.edu", "id": "Nicolet-M", "name": { "family": "Nicolet", "given": "Marc-Aurele" }, "role": "co-chair" } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_defense_date": "1974-08-01", "review_status": "approved", "option_major": { "items": [ "eleceng" ] }, "option_minor": { "items": [ "appmath" ] }, "copyright_statement": "Author's Rights Authorization: I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted here is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive license to archive and make accessible, under the conditions specified under \"Thesis Availability\" in this submission, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation, or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1975", "author_list": "Lee, Tsu-wei Frank", "advisor_list": "Mayer, James Walter; McGill, Thomas C.; et el.", "comittee_list": "Mayer, James Walter; McGill, Thomas C.; et el." }, { "id": "https://thesis.library.caltech.edu/id/eprint/14349", "eprint_id": 14349, "rev_number": 24, "documents": [ { "id": "/id/document/134864", "doc_id": 134864, "rev_number": 2, "files": [ { "id": "/id/file/382766", "fileid": 382766, "datasetid": "document", "objectid": 134864, "filename": "Marrello_V_1975.pdf", "mime_type": "application/pdf", "hash": "8fa01da55d485a2fe9f7b117291fb0fe", "hash_type": "MD5", "filesize": 32051744, "mtime": "2021-09-01 15:56:29", "url": "/14349/3/Marrello_V_1975.pdf" } ], "eprint_id": 14349, "pos": 3, "placement": 3, "mime_type": "application/pdf", "format": "application/pdf", "language": "en", "security": "public", "license": "other", "main": "Marrello_V_1975.pdf", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "final" }, { "id": "/id/document/134870", "doc_id": 134870, "rev_number": 1, "files": [ { "id": "/id/file/382809", "fileid": 382809, "datasetid": "document", "objectid": 134870, "filename": "indexcodes.txt", "mime_type": "text/plain", "hash": "3d416e545606a1c099a32e47813e283b", "hash_type": "MD5", "filesize": 16066, "mtime": "2021-09-02 19:49:18", "url": "/14349/4/indexcodes.txt" } ], "eprint_id": 14349, "pos": 4, "placement": 4, "mime_type": "text/plain", "format": "other", "format_desc": "Generate index codes conversion from application/pdf to indexcodes", "language": "en", "security": "public", "license": "other", "main": "indexcodes.txt", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "relation": { "items": [ { "type": "http://eprints.org/relation/isVersionOf", "uri": "/id/document/134864" }, { "type": "http://eprints.org/relation/isVolatileVersionOf", "uri": "/id/document/134864" }, { "type": "http://eprints.org/relation/isIndexCodesVersionOf", "uri": "/id/document/134864" } ] } } ], "eprint_status": "archive", "userid": 87, "dir": "disk0/00/01/43/49", "datestamp": "2021-09-07 17:43:06", "lastmod": "2021-09-07 17:44:02", "status_changed": "2021-09-07 17:43:06", "type": "thesis", "metadata_visibility": "show", "creators": { "items": [ { "id": "Marrello-Vincent", "name": { "family": "Marrello", "given": "Vincent" }, "show_email": "NO" } ] }, "title": "Part I. Solid-Phase Growth of Germanium Structures. Part II. Condensation of Injected Electrons and Holes in Germanium", "ispublished": "unpub", "full_text_status": "public", "keywords": "Electrical Engineering", "note": "Title in 1975 commencement program -- I. Solid-Phase Growth of Ge Structures. II. Condensation of Injected Electrons and Holes in Ge -- differs slightly from title in thesis file (PDF). Page 103 missing from thesis file (PDF).", "abstract": "Part I
\r\n\r\nSolid-solid reactions between a semiconductor and evaporated metal films can lead to semiconductor crystal growth. In this work, two aspects of solid-phase growth have been investigated; 1) growth of epitaxial Ge layers from a solid solution of Ge in an Al film onto single crystal Ge substrate (solid-phase epitaxy), and 2) growth of Ge crystallites in Al films from amorphous Ge films deposited on the Al film.
\r\n\r\nIn solid-phase epitaxial studies, backscattering measurements with MeV 4He+ ions showed that a solid-solid reaction occurred at temperatures below the Ge/Al eutectic point. Channeling effect measurements with MeV 4He+ ions indicated that the Ge layers were well-ordered and epitaxial. Electron microprobe measurements indicated the Ge layers contained Al. Hall effect measurements showed the Ge layers to be heavily p-doped. These Ge layers have been used to construct p-type contacts on p-n diodes, double injection diodes and nuclear particle detectors.
\r\n\r\nGe crystallite growth in Al films occurs when an amorphous Ge film is deposited on an Al film and is heated at temperatures below the Ge/Al eutectic point. Crystallization of Ge occurs by an initial dissolution of Ge into the Al film followed by diffusion and growth of Ge crystallites in the Al films.
\r\n\r\nThe nature of Ge crystallite growth has been studied by MeV 4He+ ion backscattering techniques, transmission electron diffractometry, scanning electron microscopy and electron microprobe analysis.
\r\n\r\nPart II
\r\n\r\nWe demonstrate for the first time that the condensation of electrons and holes in Ge can be produced by electrical injection of carriers. The condensate occurs in double injection diodes at temperatures of at least up to 5\u00b0K.
\r\n\r\nThe recombination radiation from the condensate was analysed using an infrared spectrometer. The LA- and TO-phonon assisted recombination radiation lines from the condensate occur at 709 meV and 700 meV respectively. The linewidth at half maximum of the 709 meV line is 3 meV. We measure a lifetime for the condensate of 40 \u03bcs. The radiation was emitted almost uniformly from the volume between the contacts of the double injection diode. The radiation intensity increased with increasing current and decreasing temperature.
\r\n\r\nLA-phonon assisted exciton and bound exciton recombination radiation lines at 714 meV and 712 meV respectively were observed from 7 to 15\u00b0K. Above 15\u00b0K, only the exciton line was observed. The recombination radiation lifetime of the exciton at 20\u00b0K is 6 \u03bcs.
", "date": "1975", "date_type": "degree", "id_number": "CaltechTHESIS:08312021-204039498", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechTHESIS:08312021-204039498", "related_url": { "items": [ { "description": "Article adapted for thesis chapter.", "type": "doi", "url": "https://doi.org/10.1063/1.1654169" }, { "description": "Article adapted for thesis chapter.", "type": "doi", "url": "https://doi.org/10.1002/pssa.2210130223" }, { "description": "Article adapted for thesis chapter.", "type": "doi", "url": "https://doi.org/10.1016/0029-554x(73)90640-x" }, { "description": "Article adapted for thesis chapter.", "type": "doi", "url": "https://doi.org/10.1126/science.180.4089.948" }, { "description": "Article adapted for thesis chapter.", "type": "doi", "url": "https://doi.org/10.1016/0022-3093(73)90061-6" }, { "description": "Article adapted for thesis chapter.", "type": "doi", "url": "https://doi.org/10.1063/1.1663483" }, { "description": "Article adapted for thesis chapter.", "type": "doi", "url": "https://doi.org/10.1103/physrevlett.31.593" } ] }, "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "U.S. Atomic Energy Commission" }, { "agency": "Office of Naval Research (ONR)" }, { "agency": "Air Force Office of Scientific Research (AFOSR)" }, { "agency": "IBM" }, { "agency": "Shlumberg Foundation" } ] }, "collection": "CaltechTHESIS", "reviewer": "Melissa Ray", "deposited_by": "Benjamin Perez", "deposited_on": "2021-09-07 17:43:06", "doi": "10.7907/56z0-0h91", "alt_title": { "items": [ "I. Solid-Phase Growth of Ge Structures. II. Condensation of Injected Electrons and Holes in Ge" ] }, "divisions": { "items": [ "div_eng" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "advisor" }, { "id": "McGill-T-C", "name": { "family": "McGill", "given": "Thomas C." }, "role": "co-advisor" } ] }, "thesis_committee": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "chair" }, { "id": "McGill-T-C", "name": { "family": "McGill", "given": "Thomas C." }, "role": "member" } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_defense_date": "1974-09-19", "review_status": "approved", "option_major": { "items": [ "eleceng" ] }, "copyright_statement": "Author's Rights Authorization: I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted here is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive license to archive and make accessible, under the conditions specified under \"Thesis Availability\" in this submission, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation, or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1975", "author_list": "Marrello, Vincent", "advisor_list": "Mayer, James Walter and McGill, Thomas C.", "comittee_list": "Mayer, James Walter and McGill, Thomas C." }, { "id": "https://thesis.library.caltech.edu/id/eprint/6893", "eprint_id": 6893, "rev_number": 21, "documents": [ { "id": "/id/document/14499", "doc_id": 14499, "rev_number": 4, "files": [ { "id": "/id/file/93148", "fileid": 93148, "datasetid": "document", "objectid": 14499, "filename": "Feng_jsy_1975.pdf", "mime_type": "application/pdf", "filesize": 6730763, "mtime": "2012-12-26 04:41:20", "url": "/6893/1/Feng_jsy_1975.pdf" } ], "eprint_id": 6893, "pos": 1, "mime_type": "application/pdf", "format": "application/pdf", "language": "en", "security": "public", "license": "other", "main": "Feng_jsy_1975.pdf", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "final", "relation": { "items": [ { "type": "http://eprints.org/relation/hasVolatileVersion", "uri": "/id/document/27890" }, { "type": "http://eprints.org/relation/haspreviewThumbnailVersion", "uri": "/id/document/27890" }, { "type": "http://eprints.org/relation/hasVersion", "uri": "/id/document/27890" } ] } }, { "id": "/id/document/14500", "doc_id": 14500, "rev_number": 3, "files": [ { "id": "/id/file/207801", "fileid": 207801, "datasetid": "document", "objectid": 14500, "filename": "Feng_jsy_1975.zip", "mime_type": "application/zip", "filesize": 6514304, "mtime": "2016-08-22 21:23:44", "url": "/6893/2/Feng_jsy_1975.zip" } ], "eprint_id": 6893, "pos": 2, "format": "application/zip", "format_desc": "TIFF", "language": "en", "security": "internal", "license": "other", "main": "Feng_jsy_1975.zip", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "final" }, { "id": "/id/document/27890", "doc_id": 27890, "rev_number": 2, "files": [ { "id": "/id/file/93146", "fileid": 93146, "datasetid": "document", "objectid": 27890, "filename": "preview.png", "mime_type": "image/png", "hash": "091bea720b7543ee57199daea077efdf", "hash_type": "MD5", "filesize": 20280, "mtime": "2012-12-26 04:41:20", "url": "/6893/3/preview.png" } ], "eprint_id": 6893, "pos": 3, "placement": 3, "mime_type": "image/png", "format": "image/png", "language": "en", "security": "public", "license": "other", "main": "preview.png", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "relation": { "items": [ { "type": "http://eprints.org/relation/isVolatileVersionOf", "uri": "/id/document/14499" }, { "type": "http://eprints.org/relation/ispreviewThumbnailVersionOf", "uri": "/id/document/14499" }, { "type": "http://eprints.org/relation/isVersionOf", "uri": "/id/document/14499" } ] } }, { "id": "/id/document/127295", "doc_id": 127295, "rev_number": 1, "files": [ { "id": "/id/file/372729", "fileid": 372729, "datasetid": "document", "objectid": 127295, "filename": "indexcodes.txt", "mime_type": "text/plain", "hash": "e0f536484ab87f5a1782aea380e3fea3", "hash_type": "MD5", "filesize": 4726, "mtime": "2021-06-24 01:37:47", "url": "/6893/4/indexcodes.txt" } ], "eprint_id": 6893, "pos": 4, "placement": 4, "mime_type": "text/plain", "format": "other", "format_desc": "Generate index codes conversion from application/pdf to indexcodes", "language": "en", "security": "public", "license": "other", "main": "indexcodes.txt", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "relation": { "items": [ { "type": "http://eprints.org/relation/isVersionOf", "uri": "/id/document/14499" }, { "type": "http://eprints.org/relation/isVolatileVersionOf", "uri": "/id/document/14499" }, { "type": "http://eprints.org/relation/isIndexCodesVersionOf", "uri": "/id/document/14499" } ] } } ], "eprint_status": "archive", "userid": 51, "dir": "disk0/00/00/68/93", "datestamp": "2012-04-09 15:34:28", "lastmod": "2021-01-25 22:17:34", "status_changed": "2012-04-09 15:34:28", "type": "thesis", "metadata_visibility": "show", "creators": { "items": [ { "id": "Feng-Joseph-Shao-Ying", "name": { "family": "Feng", "given": "Joseph Shao-Ying" }, "show_email": "NO" } ] }, "title": "I. Stopping cross section additivity for O-2 MeV ^4He ions in solids. II. Magnetite thin films: fabrication and electrical properties", "ispublished": "unpub", "full_text_status": "public", "keywords": "Electrical Engineering", "abstract": "Part I:
\r\n\r\nRutherford backscattering can be used to determine the depth\r\ndistribution of the constituent elements in the first micron of a sample. The interpretation of the spectra requires an accurate knowledge of the rate at which the probe ions lose their kinetic energy. The microscopic rate of energy loss, the stopping cross section, has been\r\nfairly intensively investigated, both experimentally and theoretically, in elemental targets.
\r\n\r\nIn 1905, Bragg and Kleeman proposed that the rate of energy loss in a compound is a linear superposition of the atomic stopping powers. Because of the experimental difficulties, the uncertainties in the tests of this assumption have been 5-10%. Within the sensitivities of these experiments, Bragg's rule has usually been reported to be valid at high ion velocities (E\u2273I MeV/amu). We describe two new methods of testing Bragg's rule in which the apparent sensitivity limit is below 1%.
\r\n\r\nThe first test requires that Bragg's rule be extended in the obvious way to include at toys and non-stoichiometric compounds. This experiment requires a multi-layered sample in which the components of these layers can somehow be redistributed. If there is no chemical interaction with the ambient, including the substrate, the total energy\r\nloss in this multi-layered structure should be independent of the distribution of the constituent elements. This test was applied to two-layered structures of Au-Ag, Au-Cu, Au-Al, and their alloys or compounds. The total energy loss before and after the two layers were mixed was reproducible to within 1%, as predicted by Bragg's rule.
\r\n\r\nThe second test is particularly useful in those targets in which one of the component elements(or chemical radicals) is not readily available as a separate layer. Some examples that were included in this experiment are the oxides, SiO_2 and Al_2O_3. The analytical procedure\r\nrequired that three assumptions in addition to Bragg's rule be invoked. When this procedure was applied to MgO, SiO_2, Al_2O_3, Fe_2O_3 and Fe_3O_4, it was possible to demonstrate that there is a unique contribution by oxygen\r\nto the molecular stopping cross sections of these compounds. However, this value is apparently 6-22% lower than the value expected from the measured stopping cress section of molecular O_2 in the gas phase.
\r\n\r\nPart II:
\r\n\r\nA low-temperature process for manufacturing magnetite (Fe_3O_4) thin films by converting hematite(\u03b1-Fe_2O_3) thin films is described. The films produced are unambiguously identified as magnetite.
\r\n\r\nResistivity, dc Hall effect and transverse magnetoreslstance measurements were performed on these films from 104\u00b0K to room temperature. The Verwey transition is observed at 123\u00b0K, about 4\u00b0K higher than reported for stoichiometric bulk magnetite. The ordinary and extraordinary Hall coefficients are both negative over the entire temperature range, consistent with negatively charged carriers. The extraordinary Hall coefficient exhibits a \u03c1^(1/3) dependence on the resistivity above T_V and a \u03c1^(2/3) dependence below T_V. The magnetoresistance\r\nis negative at all temperatures and field strengths and its magnitude increases monotonically with the magnetic field at all temperatures. The planar Hall effect signal was below the sensitivity of the present experiment.
\r\n\r\nOne particular anomalous result observed in these measurements is the elevated Verwey transition temperature. To account for this unusual behavior, the Verwey transition in magnetite thin films was investigated by measuring the temperature dependence of the sheet resistivity. It was demonstrated that substrate-induced stresses are responsible for the elevated Verwey transition temperature. The ratio of the resistances in the two states, as evaluated at the transition temperature, is apparently proportional to the thickness of the film and independent of the substrate. The combination of these two results suggests that there is a 600-1200 \u00c5 layer that remains in the high conductivity state at all temperatures and that it is probably at the free surface of the magnetite film.
", "date": "1975", "date_type": "degree", "id_number": "CaltechTHESIS:04062012-150944579", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechTHESIS:04062012-150944579", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "collection": "CaltechTHESIS", "reviewer": "BP", "deposited_by": "Tony Diaz", "deposited_on": "2012-04-09 15:34:28", "doi": "10.7907/1C3P-AH34", "divisions": { "items": [ "div_eng" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Nicolet-M", "name": { "family": "Nicolet", "given": "Marc-Aurele" }, "role": "advisor" }, { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "advisor" } ] }, "thesis_committee": { "items": [ { "id": "Nicolet-M", "name": { "family": "Nicolet", "given": "Marc-Aurele" }, "role": "chair" }, { "id": "Wilts-C-H", "name": { "family": "Wilts", "given": "Charles Harold" }, "role": "member" }, { "id": "McGill-T-C", "name": { "family": "McGill", "given": "Thomas C." }, "role": "member" } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_defense_date": "1974-09-12", "review_status": "approved", "option_major": { "items": [ "eleceng" ] }, "copyright_statement": "Author's Rights Authorization: I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted here is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive license to archive and make accessible, under the conditions specified under \"Thesis Availability\" in this submission, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation, or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1975", "author_list": "Feng, Joseph Shao-Ying", "advisor_list": "Nicolet, Marc-Aurele and Mayer, James Walter", "comittee_list": "Nicolet, Marc-Aurele; Wilts, Charles Harold; et el." }, { "id": "https://thesis.library.caltech.edu/id/eprint/14101", "eprint_id": 14101, "rev_number": 25, "documents": [ { "id": "/id/document/114594", "doc_id": 114594, "rev_number": 2, "files": [ { "id": "/id/file/352252", "fileid": 352252, "datasetid": "document", "objectid": 114594, "filename": "Pashley_RD_1974.pdf", "mime_type": "application/pdf", "hash": "389d1ef35c26db37a86a294f906f74f1", "hash_type": "MD5", "filesize": 43829216, "mtime": "2021-03-10 18:42:04", "url": "/14101/1/Pashley_RD_1974.pdf" } ], "eprint_id": 14101, "pos": 1, "placement": 1, "mime_type": "application/pdf", "format": "application/pdf", "language": "en", "security": "public", "license": "other", "main": "Pashley_RD_1974.pdf", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "final" }, { "id": "/id/document/114595", "doc_id": 114595, "rev_number": 4, "files": [ { "id": "/id/file/352256", "fileid": 352256, "datasetid": "document", "objectid": 114595, "filename": "Pashley_RD_1974.zip", "mime_type": "application/zip", "hash": "da92d38cf79ba9c99d975f97d762c32a", "hash_type": "MD5", "filesize": 142422017, "mtime": "2021-03-10 18:45:40", "url": "/14101/2/Pashley_RD_1974.zip" } ], "eprint_id": 14101, "pos": 2, "placement": 2, "mime_type": "application/zip", "format": "application/zip", "format_desc": "TIFFs", "language": "en", "security": "internal", "license": "other", "main": "Pashley_RD_1974.zip", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "archival" }, { "id": "/id/document/131514", "doc_id": 131514, "rev_number": 1, "files": [ { "id": "/id/file/376953", "fileid": 376953, "datasetid": "document", "objectid": 131514, "filename": "indexcodes.txt", "mime_type": "text/plain", "hash": "45d86d0ee139e7ed0657884754a5948d", "hash_type": "MD5", "filesize": 17303, "mtime": "2021-06-24 18:00:31", "url": "/14101/3/indexcodes.txt" } ], "eprint_id": 14101, "pos": 3, "placement": 3, "mime_type": "text/plain", "format": "other", "format_desc": "Generate index codes conversion from application/pdf to indexcodes", "language": "en", "security": "public", "license": "other", "main": "indexcodes.txt", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "relation": { "items": [ { "type": "http://eprints.org/relation/isVersionOf", "uri": "/id/document/114594" }, { "type": "http://eprints.org/relation/isVolatileVersionOf", "uri": "/id/document/114594" }, { "type": "http://eprints.org/relation/isIndexCodesVersionOf", "uri": "/id/document/114594" } ] } } ], "eprint_status": "archive", "userid": 87, "dir": "disk0/00/01/41/01", "datestamp": "2021-03-16 16:58:26", "lastmod": "2021-03-16 16:58:50", "status_changed": "2021-03-16 16:58:26", "type": "thesis", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pashley-Richard-Dana", "name": { "family": "Pashley", "given": "Richard Dana" }, "show_email": "NO" } ] }, "title": "Electrical Properties of Ion Implanted Layers in Silicon and Gallium Arsenide", "ispublished": "unpub", "full_text_status": "public", "keywords": "Electrical Engineering", "abstract": "Part I
\r\n\r\nWith the advent of ion implantation, it has become possible to introduce many new dopant species into silicon. The electrical behavior of implanted species displaying deep energy levels was investigated in this work. Hall effect and sheet resistivity measurements were taken as a function of temperature to determine the carrier concentration, mobility, compensation, and impurity ionization energy in the implanted layers. However, since these electrical parameters varied with depth in the samples, conventional Hall effect methods were inadequate. Special differential Hall techniques were developed to characterize the inhomogeneous samples.
\r\n\r\nThe validity of this differential technique was demonstrated by investigating the doping effects of indium in silicon. Differential measurements were first made on samples shallow diffused with indium. Then the results were compared with bulk values that had been obtained in a uniformly doped sample by standard methods. In addition, studies were made on indium implanted silicon to determine the influence of radiation effects. In all three cases an indium acceptor level of 160 meV was observed. Mobility plots versus temperature were also consistent with bulk measurements. However, significant compensation effects were noticed in the implanted layers.
\r\n\r\nWith the analysis technique experimentally confirmed, the electrical behavior of tellurium implanted silicon was investigated. Samples were implanted with several doses to study the electrical activity as a function of impurity concentration. Isothermal anneal cycles were performed to determine the anneal temperature necessary to attain peak electrical activity. After anneal, differential Hall measurements were made from 100\u00b0 to 278\u00b0K to characterize the implanted layers. Tellurium was found to behave as a donor with an energy level of 140 meV in ion implanted silicon. For room temperature e1ectron densities above 1017 carriers/cm3, the ionization energy was observed to decrease. In conjunction with this decrease, the doping efficiency of ion implanted tellurium was also observed to decrease for concentrations in excess of 1017/cm3. Both of these effects were attributed to the influence of energy level broadening.
\r\n\r\nPart II
\r\n\r\nIon implantation was investigated as a doping process for the fabrication of submicron n-type layers in GaAs. Tellurium implantation was performed as a function of dose (3 x 1013 - 1 x 1015 Te/cm2) and substrate temperature (23\u00b0C - 350\u00b0C). After implantation, a protective dielectric coating was sputtered on the samples to prevent the GaAs from disassociating during the anneal. The protective qualities of three dielectrics (SiO2, Si3N4, AlN) were compared. Anneal temperatures ranged from 750\u00b0C to 950\u00b0C. The residual radiation damage and defects in the implanted layers were studied by photoluminescence and Rutherford backscatteringmeasurements. The electrical characteristics were analyzed by Schottky barrier capacitance-voltage and Hall effect measurements. Sequential Hall measurements in conjunction with layer removal were used to determine the carrier concentration and mobility profiles in the implanted layers. In addition, junction capacitance-voltae and current-voltage measurements were performed to evaluate the quality of implanted diodes.
\r\n\r\nThe samples implanted at room temperature and subsequently annealed with a SiO2 protective coating displayed almost no electrical activity and had intrinsic regions extending several microns into the GaAs. In contrast, high electrical activity was observed in samples implanted at elevated temperatures followed by anneal with a Si3N4 coating. A doping efficiency of 50% was achieved with a carrier density approaching the maximum attainable in tellurium doped GaAs (7 x 1018 electrons/cm3). However, the electrical activity varied over a wide range for samples with identical implant conditions. This scatter in the electrical measurements was attributed to the poor adherence of the Si3N4 layers to the GaAs surface during the anneal.
\r\n\r\nThe maximum electrical activity achieved using an AlN encapsulent was comparable to the value attained using a Si3N4 coating. However, the electrical activity was consistently high for the AlN protected samples and the AlN displayed better adherence to the GaAs during anneal than Si3N4.
", "date": "1974", "date_type": "degree", "id_number": "CaltechTHESIS:03102021-184153613", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechTHESIS:03102021-184153613", "related_url": { "items": [ { "description": "Conference paper adapted for chapter in thesis.", "type": "doi", "url": "https://doi.org/10.1007/978-3-642-80660-5_65" }, { "description": "Article adapted for chapter in thesis.", "type": "doi", "url": "https://doi.org/10.1080/00337577108230459" }, { "description": "Article adapted for chapter in thesis.", "type": "doi", "url": "https://doi.org/10.1063/1.321347" }, { "description": "Article adapted for chapter in thesis.", "type": "doi", "url": "https://doi.org/10.1063/1.1654271" }, { "description": "Conference paper adapted for chapter in thesis.", "type": "doi", "url": "https://doi.org/10.1007/978-1-4684-2064-7_55" }, { "description": "Article", "type": "related", "url": "https://doi.org/10.1109/JSSC.1976.1050799" }, { "description": "Article", "type": "related", "url": "https://doi.org/10.1088/0022-3719/8/7/017" } ] }, "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "Caltech" }, { "agency": "Air Force Cambridge Research Center (AFCRC)" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)" } ] }, "collection": "CaltechTHESIS", "reviewer": "Melissa Ray", "deposited_by": "Benjamin Perez", "deposited_on": "2021-03-16 16:58:26", "doi": "10.7907/gat7-kp43", "divisions": { "items": [ "div_eng" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "advisor" } ] }, "thesis_committee": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "member" }, { "email": "carver@caltech.edu", "id": "Mead-C", "name": { "family": "Mead", "given": "Carver" }, "role": "member" }, { "id": "McCaldin-J-O", "name": { "family": "McCaldin", "given": "James Oeland" }, "role": "member" }, { "email": "man@caltech.edu", "id": "Nicolet-M", "name": { "family": "Nicolet", "given": "Marc-Aurele" }, "role": "member" } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_defense_date": "1974-01-10", "review_status": "approved", "option_major": { "items": [ "eleceng" ] }, "copyright_statement": "Author's Rights Authorization: I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted here is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive license to archive and make accessible, under the conditions specified under \"Thesis Availability\" in this submission, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation, or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1974", "author_list": "Pashley, Richard Dana", "advisor_list": "Mayer, James Walter", "comittee_list": "Mayer, James Walter; Mead, Carver; et el." }, { "id": "https://thesis.library.caltech.edu/id/eprint/14060", "eprint_id": 14060, "rev_number": 29, "documents": [ { "id": "/id/document/114269", "doc_id": 114269, "rev_number": 2, "files": [ { "id": "/id/file/350166", "fileid": 350166, "datasetid": "document", "objectid": 114269, "filename": "Lugujjo_e_1974.pdf", "mime_type": "application/pdf", "hash": "261b6a46651d2287ef82853efda1ca35", "hash_type": "MD5", "filesize": 34379951, "mtime": "2021-01-28 19:27:31", "url": "/14060/1/Lugujjo_e_1974.pdf" } ], "eprint_id": 14060, "pos": 1, "placement": 1, "mime_type": "application/pdf", "format": "application/pdf", "language": "en", "security": "public", "license": "other", "main": "Lugujjo_e_1974.pdf", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "final" }, { "id": "/id/document/114270", "doc_id": 114270, "rev_number": 4, "files": [ { "id": "/id/file/350168", "fileid": 350168, "datasetid": "document", "objectid": 114270, "filename": "Lugujjo_e_1974 .zip", "mime_type": "application/zip", "hash": "095d12429abcbbec0155d70c7dc75f4e", "hash_type": "MD5", "filesize": 113516377, "mtime": "2021-01-28 19:31:48", "url": "/14060/2/Lugujjo_e_1974 .zip" } ], "eprint_id": 14060, "pos": 2, "placement": 2, "mime_type": "application/zip", "format": "application/zip", "format_desc": "TIFFs", "language": "en", "security": "internal", "license": "other", "main": "Lugujjo_e_1974 .zip", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "archival" }, { "id": "/id/document/131451", "doc_id": 131451, "rev_number": 1, "files": [ { "id": "/id/file/376890", "fileid": 376890, "datasetid": "document", "objectid": 131451, "filename": "indexcodes.txt", "mime_type": "text/plain", "hash": "ac0502a5f7bde04b85ec95e7cbfe69b7", "hash_type": "MD5", "filesize": 23369, "mtime": "2021-06-24 17:55:13", "url": "/14060/3/indexcodes.txt" } ], "eprint_id": 14060, "pos": 3, "placement": 3, "mime_type": "text/plain", "format": "other", "format_desc": "Generate index codes conversion from application/pdf to indexcodes", "language": "en", "security": "public", "license": "other", "main": "indexcodes.txt", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "relation": { "items": [ { "type": "http://eprints.org/relation/isVersionOf", "uri": "/id/document/114269" }, { "type": "http://eprints.org/relation/isVolatileVersionOf", "uri": "/id/document/114269" }, { "type": "http://eprints.org/relation/isIndexCodesVersionOf", "uri": "/id/document/114269" } ] } } ], "eprint_status": "archive", "userid": 2032, "dir": "disk0/00/01/40/60", "datestamp": "2021-01-29 00:47:21", "lastmod": "2021-01-30 00:19:41", "status_changed": "2021-01-29 00:47:21", "type": "thesis", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lugujjo-Eriabu", "name": { "family": "Lugujjo", "given": "Eriabu" }, "show_email": "NO" } ] }, "title": "I. Backscattering and Channeling Effect Studies on Semiconductor-Metal Systems. II. Low Temperature Migration of Silicon through Metal Films", "ispublished": "unpub", "full_text_status": "public", "keywords": "Electrical Engineering", "abstract": "PART I
\r\n\r\nChanneling measurements by backscattering of He and H ions have been made on <111>- and <110>-oriented Si covered with evaporated layers of Al and Au. The energy range was 0.4 - 1.8 MeV and the film thicknesses ranged between 100 and 1100\u00c5 for Au, and between 900 and 3000\u00c5 for Al. As a first approach to analysis of disorder in crystals, we have investigated the effects of simulated disorder in form of metal layers on the surface of Si and Ge. This has an advantage in that particle scattering in the metal films can be controlled independently of scattering in the underlying substrate. The minimum yield, half-width of the angular-yield profile and the depth dependence of aligned yield have been studied as a function of metal-film thickness and beam energy. Comparisons between experimental and calculated values have been made on the basis of two different treatments of plural scattering.
\r\n\r\nThe minimum yield values obtained by applying only a step-function approximation to the angular yield profile were first evaluated as a function of film thickness. The minimum yield, angular-yield profiles and dechanneling dependence on depth obtained witl1 Al films follow the predictions of Meyer's treatment of plural scattering.
\r\n\r\nA detailed study of minimum yield values on covered Si was then made. In this case the minimum yield was calculated from the Meyer treatment and probability curves determined from (i) a step-function approximation to the angular-yield profile, and (ii) two different axial scans on uncovered Si, one of which is azimuthally averaged. The minimum yields calculated using the step-function approximation and average probability curves are in good agreement with experimental results. This suggests that the step-function approximation, although less accurate than the azimuthally averaged procedure, is adequate for use with investigations of disorder in crystals by channeling-effect measurements. On the basis of the step function approximation, we have established universal curves from which minimum yield values as a function of disorder may be obtained.
\r\n\r\nPART II
\r\n\r\nThe backscattering spectrometry using 2 MeV He\u207a ions have been employed to study the phenomenon of low temperature migration of Si through thin films of Au and Ag evaporated on <110> and <111> Si single crystal substrates. The thicknesses of Au films ranged from 200 to 4000\u00c5, and those of Ag from 200 to 800\u00c5. Migration of Si into these metal films is observed when the systems are heat treated in an oxidizing ambient at low temperatures (150\u00b0C for Au, 400\u00b0C for Ag), well below their eutectic points (375\u00b0C for Au and 830\u00b0C for Ag).
\r\n\r\nThe migration of Si is followed by formation of a silicon-oxide layer on top of the metal film. The initial growth of this oxide layer is proportional to (time)\u00bd. The factors controlling this low-temperature oxide formation have been investigated. Both oxidizing ambient and orientation of the substrate influence the oxide growth rate, and the thickness of evaporated film determines the final thickness of the oxide. A model to explain the oxide-growth mechanism is presented.
\r\n\r\nThe migration of Si also has been studied through layers of Au with superimposed layers of Ag, and vice versa. It is found that the interface between Si and the metal film plays a leading role in these low-temperature migration studies.
", "date": "1974", "date_type": "degree", "id_number": "CaltechTHESIS:01282021-190841642", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechTHESIS:01282021-190841642", "related_url": { "items": [ { "description": "Channeling in Si Overlaid with Al and Au Films", "type": "doi", "url": "https://doi.org/10.1103/PhysRevB.6.718" }, { "description": "Low-temperature migration of silicon through metal films: importance of silicon-metal interface", "type": "doi", "url": "https://doi.org/10.1002/pssa.2210070212" }, { "description": "Formation of silicon oxide over gold layers on silicon substrates", "type": "doi", "url": "https://doi.org/10.1063/1.1661782" }, { "description": "Low-Temperature Migration of Silicon in Metal Films on Silicon Substrates Studied by Backscattering Techniques", "type": "doi", "url": "https://doi.org/10.1116/1.1316540" }, { "description": "Optical Line and Broad-Band Emission from Ion-Bombarded Targets", "type": "doi", "url": "https://doi.org/10.1007/978-1-4615-8996-9_4" }, { "description": "Stoichiometry of thin silicon oxide layers on silicon", "type": "doi", "url": "https://doi.org/10.1063/1.1655112" } ] }, "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "collection": "CaltechTHESIS", "reviewer": "Melissa Ray", "deposited_by": "Kristofer Jolley", "deposited_on": "2021-01-29 00:47:21", "doi": "10.7907/0zd4-s880", "alt_title": { "items": [ "Backscattering and Channeling Effect Studies on Semiconductor-Metal Systems", "Low Temperature Migration of Silicon through Metal Films" ] }, "divisions": { "items": [ "div_eng" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "advisor" } ] }, "thesis_committee": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "member" } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_defense_date": "1974-01-29", "review_status": "approved", "option_major": { "items": [ "eleceng" ] }, "copyright_statement": "Author's Rights Authorization: I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted here is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive license to archive and make accessible, under the conditions specified under \"Thesis Availability\" in this submission, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation, or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1974", "author_list": "Lugujjo, Eriabu", "advisor_list": "Mayer, James Walter", "comittee_list": "Mayer, James Walter" }, { "id": "https://thesis.library.caltech.edu/id/eprint/1349", "eprint_id": 1349, "rev_number": 16, "documents": [ { "id": "/id/document/2062", "doc_id": 2062, "rev_number": 2, "files": [ { "id": "/id/file/12857", "fileid": 12857, "datasetid": "document", "objectid": 2062, "filename": "Bower_rw_1973.pdf", "mime_type": "application/pdf", "filesize": 5277518, "mtime": "2012-12-26 02:37:28", "url": "/1349/1/Bower_rw_1973.pdf" } ], "eprint_id": 1349, "pos": 1, "mime_type": "application/pdf", "format": "application/pdf", "format_desc": "Bower_rw_1973.pdf", "language": "en", "security": "public", "license": "other", "main": "Bower_rw_1973.pdf", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "content": "final", "relation": { "items": [ { "type": "http://eprints.org/relation/hasVolatileVersion", "uri": "/id/document/18827" }, { "type": "http://eprints.org/relation/haspreviewThumbnailVersion", "uri": "/id/document/18827" }, { "type": "http://eprints.org/relation/hasVersion", "uri": "/id/document/18827" } ] } }, { "id": "/id/document/18827", "doc_id": 18827, "rev_number": 2, "files": [ { "id": "/id/file/12855", "fileid": 12855, "datasetid": "document", "objectid": 18827, "filename": "preview.png", "mime_type": "image/png", "hash": "2de501e37f5878e10d65a53e238f293c", "hash_type": "MD5", "filesize": 8166, "mtime": "2012-12-26 02:37:28", "url": "/1349/2/preview.png" } ], "eprint_id": 1349, "pos": 2, "placement": 2, "mime_type": "image/png", "format": "image/png", "language": "en", "security": "public", "license": "other", "main": "preview.png", "media_duration": "0", "media_aspect_ratio": "0", "media_sample_start": "0", "media_sample_stop": "0", "relation": { "items": [ { "type": "http://eprints.org/relation/isVolatileVersionOf", "uri": "/id/document/2062" }, { "type": "http://eprints.org/relation/ispreviewThumbnailVersionOf", "uri": "/id/document/2062" }, { "type": "http://eprints.org/relation/isVersionOf", "uri": "/id/document/2062" } ] } } ], "eprint_status": "archive", "userid": 2, "dir": "disk0/00/00/13/49", "datestamp": "2004-04-14", "lastmod": "2021-07-22 19:10:26", "status_changed": "2009-09-25 02:02:06", "type": "thesis", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bower-Robert-William", "name": { "family": "Bower", "given": "Robert William" }, "show_email": "NO" } ] }, "title": "Reaction Kinetics of Pd and Ti-Al Films on Si", "ispublished": "unpub", "full_text_status": "public", "keywords": "(Applied Physics)", "abstract": "The growth of compound phases from thin film layers of Pd and Ti-Al deposited on Si is described in this work. The growth kinetics and composition of the compound phases were measured utilizing 2 MeV \u2074He backscattering. Crystalline structure and film texture effects of the compounds layers were measured by X-ray diffraction techniques.
\r\n\r\nThe Pd-Si system was first studied by depositing 1000 to 3000\u00c5 of Pd onto a Si substrate and heating to 200 to 700\u00b0C. A single phase of material with a composition Pd2Si developed when specimens were heated to a temperature of 200\u00b0C. The phase grows at a rate proportional to (time)1/2 indicating transport limited growth. The temperature dependence of the growth constant was found to be expressible as a single activation energy of approximately 1.5 eV over the 200 to 275\u00b0C temperature range where growth kinetics were measured.
\r\n\r\nThe X-ray diffraction data indicated that the Pd2Si phase which formed has the crystalline structure of Pd2Si known from metallurgical studies of bulk materials. The Pd2Si layers which formed from the thin film structures were found to be oriented with the hexagonal basal plane parallel to the substrate material. The degree of the preferred orientation of the Pd2Si depends on the Si substrate orientation. By far the highest degree of orientation was found when the Pd2Si was formed on <lll>-Si.
\r\n\r\nThe more complex Si-Ti-Al system is treated following the Pd-Si system. In this case a layer of Ti and then Al was evaporated on Si after which the specimens were heated to temperatures of 400\u00b0 to 500\u00b0C. Backscattering of \u2074He ions was used to measure growth kinetics and composition of compound phases which develop. While the spectra are more complex the same basic analysis techniques developed for the Pd-Si system were applicable. While no measurable reaction of the Si and Ti was found in this temperature range, the Ti-Al reacts to form a phase of TiAl\u2083. The rate of formation of TiAl\u2083 was also found to be proportional to (time)1/2 indicating transport limited growth. The temperature dependence of the growth constant was found to be again expressible by a single activation energy over the temperature range measured. The value of activation energy was found to be approximately 1.85 eV.
\r\n\r\nThe X-ray diffraction analysis indicates that a single phase of TiAl3 forms until the entire Ti layer is consumed. At this point Si reacts with the system displacing most of the Al to form a Si-rich Ti-Al-Si ternary phase.
\r\n\r\nThe Ti-Al metal system is used to make contact to Si in integrated circuit applications. The TiAl\u2083 and subsequent Si-rich Ti-Al-Si ternary formation in this system can be directly related to severe erosion of metal -Si contact areas which result in failure of the integrated circuits.
\r\n\r\nThe measured rate of formation of TiAl\u2083 found from the backscattering measurements allows the thickness of Ti to be chosen large enough so that heat treatments following metal deposition will not cause contact failure. Thus, the rate kinetics of TiAl3 formation measured by 2 MeV \u2074He backscattering is found to have practical application in predicting and controlling a failure mechanism in an integrated circuit metallization scheme.
", "date": "1973", "date_type": "degree", "id_number": "CaltechETD:etd-04122004-132122", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechETD:etd-04122004-132122", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "collection": "CaltechTHESIS", "reviewer": "Kathy Johnson", "local_group": { "items": [ "Caltech Distinguished Alumni Award" ] }, "deposited_by": "Imported from ETD-db", "deposited_on": "2004-04-14", "doi": "10.7907/NY05-4E97", "divisions": { "items": [ "div_eng" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "advisor" }, { "id": "Nicolet-M", "name": { "family": "Nicolet", "given": "Marc-Aurele" }, "role": "advisor" } ] }, "thesis_committee": { "items": [ { "name": { "family": "Unknown", "given": "Unknown" } } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_submitted_date": "2004-04-12", "thesis_defense_date": "1973-04-30", "thesis_approved_date": "2004-04-14", "thesis_awards": "Caltech Distinguished Alumni Award, 2001", "review_status": "approved", "option_major": { "items": [ "appliedphys" ] }, "copyright_statement": "I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive\nlicense to archive and make accessible, under the conditions specified below,\nmy thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1973", "author_list": "Bower, Robert William", "advisor_list": "Mayer, James Walter and Nicolet, Marc-Aurele", "comittee_list": "Unknown, Unknown" }, { "id": "https://thesis.library.caltech.edu/id/eprint/10389", "eprint_id": 10389, "rev_number": 23, "documents": [ { "id": "/id/document/82253", "doc_id": 82253, "rev_number": 2, "files": [ { "id": "/id/file/232345", "fileid": 232345, "datasetid": "document", "objectid": 82253, "filename": "Westmoreland_III_JE_1971.pdf", "mime_type": "application/pdf", "hash": "fb1cedf96e276806880013b56ff4f860", "hash_type": "MD5", "filesize": 36518892, "mtime": "2017-08-29 15:38:19", "url": "/10389/1/Westmoreland_III_JE_1971.pdf" } ], "eprint_id": 10389, "pos": 1, "placement": 1, "mime_type": "application/pdf", "format": "application/pdf", "language": "en", "security": "public", 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A simple description of the interactions of the analyzing beam in partially disordered samples was acceptable for obtaining the disorder peak depth and shape when applied to both helium and proton backscattering spectra. For samples held at temperatures below -45\u00b0C during implantation of between ~2 x 1014 and ~8 x 1014 boron ions/cm2, plural scattering gave self consistent results for the dechanneling mechanism. An essentially phenomenological multiple scattering treatment of dechanneling was also given for the analysis of room temperature implants. The mechanism governing the dechanneling was shown to depend on the detailed structure of the disordered layer, so an all-inclusive treatment of backscattering spectra to extract arbitrary disorder distributions was not feasible at the present time.
\r\n\r\n\r\nThe measured results for the disorder peak depths agreed well with the values for these depths calculated by D.K. Brice, but were 80-85% less than the boron projected range. The measured disorder peak widths were 60-70% less than the calculated values.
\r\n\r\n\r\nThe amount of disorder in samples held at room temperature during implantation was about a factor of twenty less than that in samples implanted at -150\u00b0C with the same dose of boron ions. Comparison of the disorder production data with the anneal of a -150\u00b0C implant showed the nonequivalence of dynamic anneal processes at a given temperature and thermal instabilities of disorder produced at lower temperatures\r\nand then warmed to the given temperature.
\r\n\r\nIt was shown that analyzing beam bombardment could effect the amount of disorder measured.
\r\n\r\nThe depth scale of the backscattering spectra was determined directly by layer removal. The composition of the anodic oxide layers employed in the layer removals was measured by a backscattering analysis. Stopping power measurements were given showing that the aligned beam stopping power as measured by backscattering was ~80% of the random value at 1.0 MeV, an energy near the maximum of the random stopping power curve for helium in silicon.
\r\n \r\n\r\n", "date": "1971", "date_type": "degree", "id_number": "CaltechTHESIS:08242017-130415823", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechTHESIS:08242017-130415823", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Air Force Cambridge Research Laboratory" }, { "agency": "NSF" }, { "agency": "Office of Naval Research" } ] }, "collection": "CaltechTHESIS", "reviewer": "Tony Diaz", "deposited_by": "Benjamin Perez", "deposited_on": "2017-08-29 16:32:11", "doi": "10.7907/K38Q-NC50", "divisions": { "items": [ "div_pma" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "advisor" } ] }, "thesis_committee": { "items": [ { "name": { "family": "Unknown", "given": "Unknown" } } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_defense_date": "1971-04-23", "review_status": "approved", "option_major": { "items": [ "physics" ] }, "copyright_statement": "Author's Rights Authorization: I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted here is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive license to archive and make accessible, under the conditions specified under \"Thesis Availability\" in this submission, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation, or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1971", "author_list": "Westmoreland, James Edward, III", "advisor_list": "Mayer, James Walter", "comittee_list": "Unknown, Unknown" }, { "id": "https://thesis.library.caltech.edu/id/eprint/10159", "eprint_id": 10159, "rev_number": 28, "documents": [ { "id": "/id/document/77822", "doc_id": 77822, "rev_number": 2, "files": [ { "id": "/id/file/220684", "fileid": 220684, "datasetid": "document", "objectid": 77822, "filename": "Picraux_ST_1969.pdf", "mime_type": "application/pdf", "hash": "0edb763cd4f1c266f2473deab917d30e", "hash_type": "MD5", "filesize": 29869346, "mtime": "2017-05-10 21:29:20", "url": "/10159/1/Picraux_ST_1969.pdf" } ], "eprint_id": 10159, "pos": 1, "placement": 1, "mime_type": "application/pdf", "format": "application/pdf", "language": "en", "security": "public", "license": "other", "main": 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measured and\r\ncompared to theory. The values of \u03c8\u00bd for axial channeling have a functional\r\ndependence which agrees well with calculations based on the average\r\npotential along the row - both for uniform and for non-uniform spacing\r\nand (in the case of the compound semiconductors) for mixed atomic\r\ncomposition. Planar critical angles also show a functional dependence\r\nin agreement with average potential calculations. However, it is necessary\r\nto include in the calculation the effect of surface transmission\r\nwhich becomes increasingly important for higher order planar directions\r\n(e.g. lower atomic density of the planes). Measured full angular distributions\r\nare compared with calculated distributions for planar channeling. \r\nFor both axial and planar channeling the measured critical\r\nangles are \u2248 25% lower in absolute magnitude than calculated.
\r\n\r\n\r\nChanneling and electrical measurements are combined to study ion\r\nimplanted impurities in silicon. The lattice disorder and impurity atom\r\nlattice location are investigated by channeling effect measurements\r\nusing a 1 MeV helium ion analyzing beam. The electrical type, number of\r\ncarriers/cm2 and mobility are determined by use of Hall effect and sheet\r\nresistivity measurements.
\r\n\r\n\r\nThe anneal behavior of Cd and Te implantations (20-50 keV) into Si\r\nat substrate temperatures of 23\u00b0C and 350\u00b0C were investigated. The room\r\ntemperature Te implants showed substitutional behavior and donor action\r\nafter anneal at 600\u00b0C. In room temperature Cd implantations, outdiffusion\r\nof the Cd was observed when the disordered layer annealed. Implantations\r\nof Cd at 350\u00b0C indicated the presence of an interstitial\r\ncomponent and n-type behavior was observed.
\r\n", "date": "1969", "date_type": "degree", "id_number": "CaltechTHESIS:05102017-142717261", "refereed": "FALSE", "official_url": "https://resolver.caltech.edu/CaltechTHESIS:05102017-142717261", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Cambridge Research Laboratory" }, { "agency": "NASA" }, { "agency": "NSF" } ] }, "collection": "CaltechTHESIS", "reviewer": "Tony Diaz", "deposited_by": "Benjamin Perez", "deposited_on": "2017-05-11 21:07:16", "doi": "10.7907/EBXR-QS35", "divisions": { "items": [ "div_eng" ] }, "institution": "California Institute of Technology", "thesis_type": "phd", "thesis_advisor": { "items": [ { "id": "Mayer-J-W", "name": { "family": "Mayer", "given": "James Walter" }, "role": "advisor" } ] }, "thesis_committee": { "items": [ { "name": { "family": "Unknown", "given": "Unknown" } } ] }, "thesis_degree": "PHD", "thesis_degree_grantor": "California Institute of Technology", "thesis_defense_date": "1969-04-30", "review_status": "approved", "option_major": { "items": [ "eng" ] }, "option_minor": { "items": [ "physics" ] }, "copyright_statement": "Author's Rights Authorization: I hereby certify that, if appropriate, I have obtained a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted here is the same as that approved by my advisory committee.\n\nI hereby grant to California Institute of Technology or its agents the non-exclusive license to archive and make accessible, under the conditions specified under \"Thesis Availability\" in this submission, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation, or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.", "resource_type": "thesis", "pub_year": "1969", "author_list": "Picraux, Samuel Thomas", "advisor_list": "Mayer, James Walter", "comittee_list": "Unknown, Unknown" } ]