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Blue-laser excitation studies of ZnO thin films and rare-earth doped ZnO powdersBhebhe, Nkosiphile Andile January 2016 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfillment of the academic requirements for the degree of Master of Science. Johannesburg, March 2016. / Zinc oxide (ZnO) continues to receive widespread attention due to its excellent optical and electronic properties; it demonstrates the combined characteristics of high transmittance and electrical conductivity. Despite the tremendous drive for its application in optoelectronic devices, the full nature of the point defects and defect complexes have not been characterised comprehensively. In this work, luminescence characteristics of the intrinsic defects in ZnO thin films and the rare-earth ions Eu3+ and Tb3+ in ZnO powders are investigated under blue-laser excitation.
The thin films used in this study were deposited using the radio-frequency magnetron sputtering method over a 2 hour duration under varied power and substrate bias conditions. The powders were synthesized by the chemical bath deposition method with dopant concentrations of 1.0 mol%. Grazing incidence X-ray diffraction (XRD) was used to determine the lattice properties of the samples. Photoluminescence studies were primarily conducted at room temperature (300 K) with the 457.9 nm, 476.5 nm and 488.0 nm laser lines as excitation sources.
For the ZnO thin films, XRD patterns of a hexagonal wurtzite structure with a c/a ratio of about 1.60 and a u-parameter of 0.38 were obtained. Photoluminescence measurements show a broad emission band in the 500.0-900.0 nm range, centred at 656.0 nm. Annealed films yielded relatively more intense photoluminescence spectra than the as-prepared films. The intrinsic point defects and defect level transitions responsible for the broad emission are discussed.
For the ZnO powders, the XRD patterns of the annealed samples of pristine ZnO, ZnO:Eu3+ and ZnO:Tb3+ are similarly consistent with a hexagonal wurtzite ZnO phase. Energy dispersive spectroscopy (EDS) confirmed the presence of the Eu3+ and Tb3+ dopants in the respective ZnO host while scanning electron microscopy (SEM) measurements showed the morphology of the sample powders. Photoluminescence spectra of pelletized samples, obtained in the 460.0-900.0 nm range, exhibit relatively intense Eu3+ and Tb3+ emission bands superimposed on a broad emission background. The RE3+ emission bands are
attributed to the 5D0 → 7FJ (J = 0, 1, 2, 3, 4) and the 5D4 → 7FJ (J = 0, 1, 2, 3, 4, 5, 6) electronic transitions of Eu3+ and Tb3+, respectively, while the background emission is attributed to intrinsic defects. Crystal-field energy levels for the Eu3+ ion and the Tb3+ ion occupying a C3v symmetry site were deduced from fitting Gaussian curves to the RE3+ emission bands. Possible channels for transfer of energy from the intrinsic defects to Eu3+ and Tb3+ are discussed. / LG2017
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Geometric photovoltaics applied to amorphous silicon thin film solar cellsKirkpatrick, Timothy January 2012 (has links)
Thesis advisor: Michael J. Naughton / Geometrically generalized analytical expressions for device transport are derived from first principles for a photovoltaic junction. Subsequently, conventional planar and unconventional coaxial and hemispherical photovoltaic architectures are applied to detail the device physics of the junction based on their respective geometry. For the conventional planar cell, the one-dimensional transport equations governing carrier dynamics are recovered. For the unconventional coaxial and hemispherical junction designs, new multi-dimensional transport equations are revealed. Physical effects such as carrier generation and recombination are compared for each cell architecture, providing insight as to how non-planar junctions may potentially enable greater energy conversion efficiencies. Numerical simulations are performed for arrays of vertically aligned, nanostructured coaxial and hemispherical amorphous silicon solar cells and results are compared to those from simulations performed for the standard planar junction. Results indicate that fundamental physical changes in the spatial dependence of the energy band profile across the intrinsic region of an amorphous silicon p-i-n junction manifest as an increase in recombination current for non-planar photovoltaic architectures. Despite an increase in recombination current, however, the coaxial architecture still appears to be able to surpass the efficiency predicted for the planar geometry, due to the geometry of the junction leading to a decoupling of optics and electronics. / Thesis (PhD) — Boston College, 2012. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Physics.
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CuxS/ZnyCd1-yS polycrystalline thin film solar cells using chemical-sprayed techniques.January 1982 (has links)
by Leung Ming-yuen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1982 / Bibliography: leaves 174-177
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Preparation of PZT thin films by pulsed laser deposition.January 1992 (has links)
by Au Wing Shing. / Parallel title in Chinese characters. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 56-58). / Acknowledgements --- p.i / Abstract --- p.ii / Table of Content --- p.iii / Chapter CHATPER 1 : --- INTRODUCTION --- p.1 / Chapter CHAPTER 2 : --- EXPERIMENTAL SET-UP / Chapter A. --- General Description --- p.4 / Chapter B. --- Vacuum System and Chamber --- p.6 / Chapter C. --- Target Rotation and Motor Connection --- p.7 / Chapter D. --- Substrate Heating and Temperature Control --- p.8 / Chapter E. --- Pressure and Flow Control --- p.9 / Chapter CHAPTER 3 : --- THICKNESS AND COMPOSITION DISTRIBUTIONS OF FILMS DEPOSITED AT ROOM TEMPERATURE / Chapter A. --- Experimental Details --- p.10 / Chapter B. --- Shape of the Plume --- p.12 / Chapter C. --- Effect of Laser Fluence --- p.15 / Chapter D. --- Investigation of the Pb Deficiency in the Deposited Film --- p.24 / Chapter E. --- Effect of Oxygen Pressure --- p.27 / Chapter CHAPTER 4 : --- TARGET MODIFICATION AND DEPOSITION RATE / Chapter A. --- Introduction --- p.34 / Chapter B. --- Experimental Details --- p.40 / Chapter C.i. --- Result 1 : Normal Incidence Case --- p.41 / Chapter ii. --- Result 2 : 45° Incidence Case --- p.42 / Chapter D. --- Discussion --- p.43 / Chapter CHAPTER 5 : --- HIGH TEMPERATURE GROWTH ON DIFFERRENT KINDS OF SUBSTRATES / Chapter A. --- Introduction --- p.45 / Chapter B. --- Experimental Details --- p.47 / Chapter C. --- High Temperature Growth / Chapter i. --- Films grown on MgO (100) --- p.49 / Chapter ii. --- Films grown on Spinel --- p.50 / Chapter iii. --- Films grown on c-plane Sapphire --- p.51 / Chapter D. --- Discussion --- p.52 / Chapter CHAPTER 6 : --- OVERALL CONCLUSION AND FURTHER WORKS --- p.54 / References --- p.56 / Appendix1 --- p.59 / Appendix2 --- p.61
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Structural and composition analysis of high Tc superconducting YBa2Cu3O7-x thin films on spinel.January 1992 (has links)
by Siu Wing Hon. / On t.p. T"c", "2", "3", and "7-x" are subscripts following "superconducting" in the title. / Parallel title in Chinese characters. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves [79]-[80]). / Acknowledgement --- p.i / Abstract --- p.ii / Table of Content --- p.iii / Chapter Chapter 1 : --- Introduction / Chapter Chapter 2 : --- Growth of YBCO on Spinel / Chapter 2-1. --- Why Spinel --- p.2-1 / Chapter 2-2. --- Film Deposition Technique --- p.2-3 / Chapter 2-2.1 --- Magnetron Sputtering Technique --- p.2-3 / Chapter 2-2.2 --- Pulsed Laser Ablation --- p.2-4 / Chapter Chapter 3 : --- Composition Analysis by XRF / Chapter 3-1. --- Introduction --- p.3-1 / Chapter 3-2. --- Minimum Penetration Depth of EDX for YBCO film --- p.3-5 / Chapter 3-3. --- Thin Film Method and Thin Film Limit --- p.3-9 / Chapter 3-4. --- XRF Setup --- p.3-14 / Chapter 3-5. --- Calibration --- p.3-14 / Chapter 3-5.1 --- Chemical method --- p.3-18 / Chapter 3-5.2 --- Absorption Factor --- p.3-18 / Chapter 3-5.3 --- Diffusion Rate --- p.3-22 / Chapter 3-5.4 --- Justification of Thin Film Method --- p.3-22 / Chapter 3-5.5 --- Result of Calibration by Chemical Method --- p.3-24 / Chapter 3-5.6 --- Calibration by Rutherford Backscattering --- p.3-28 / Chapter 3-6. --- Discussion on XRF --- p.3-31 / Chapter 3-6.1 --- Effect of diffraction line by substrate on X-ray spectrum --- p.3-31 / Chapter 3-6.2 --- Stability of X-ray power supply and its influence on spectrum --- p.3-34 / Chapter Chapter 4 : --- Structural Analysis and Rapid Thermal Annealing / Chapter 4-1. --- XRD Setup --- p.4-1 / Chapter 4-2. --- XRD Analysis --- p.4-2 / Chapter 4-2.1 --- θ-2θ Scan --- p.4-1 / Chapter 4-2.2 --- Phi Scan --- p.4-3 / Chapter 4-2.3 --- Study of Diffraction Peak --- p.4-9 / Chapter 4-3. --- RTA and its influence on structure --- p.4-11 / Chapter 4-3.1 --- RTA Setup --- p.4-13 / Chapter 4-3.2 --- Structural Improvement by RTA --- p.4-13 / Chapter Chapter 5 : --- Conclusion --- p.5-1 / Chapter Appendix : A. --- Mathematical Derivation of Thin Film Limit / Chapter B. --- Powder Diffraction Patterns of YBCO system / Reference
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Epitaxial growth of oxide thin films.January 1994 (has links)
Ling Siu-hing. / Title also in Chinese characters. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 220-227). / ACKNOWLEDGEMENT --- p.i / ABSTRACT --- p.ii / Chapter Chapter 1 --- Ceramic thin film --- p.1 / Chapter 1. 1 --- """New stone era""---the importance of ceramics" --- p.1 / Chapter 1.2 --- The importance of epitaxial growth of YBCO films --- p.4 / Chapter 1.3 --- The importance of epitaxial growth of PZT films --- p.9 / Chapter 1.4 --- The similar structures of YBCO and PZT --- p.10 / Chapter Chapter 2 --- Epitaxy --- p.12 / Chapter 2. 1 --- Introduction --- p.12 / Chapter 2.2 --- Basic principle --- p.13 / Chapter Chapter 3 --- Sample preparation Techniques --- p.25 / Chapter 3.1 --- A glimpse at epitaxial film deposition --- p.25 / Chapter 3.2 --- Magnetron sputtering --- p.28 / Chapter 3.2.1 --- Principle --- p.28 / Chapter 3.2.2 --- Set-ups --- p.30 / Chapter 3.2.3 --- High pressure magnetron sputter gun --- p.33 / Chapter 3.2.4 --- Type II unbalanced magnetron gun modification --- p.42 / Chapter 3.3 --- Pulsed Laser Deposition (PLD) --- p.54 / Chapter 3.4 --- Rapid thermal annealing (RTA) --- p.62 / Chapter Chapter 4 --- Characterizations-principles and setups --- p.66 / Chapter 4.1 --- Structure-X-ray diffractometer --- p.66 / Chapter 4.1.1 --- Setup --- p.57 / Chapter 4.1.2 --- Characterization --- p.71 / Chapter 4.1.3 --- High temperature X-ray diffractometer (HTXRD) --- p.83 / Chapter 4.2 --- Surface morphology --- p.86 / Chapter 4.2.1 --- Scanning electron microscopy (SEM) --- p.86 / Chapter 4. 3 --- Composition --- p.89 / Chapter 4.3.1 --- Energy dispersive X-ray spectroscopy --- p.89 / Chapter 4.3.2 --- Rutherford backscattering spectrometry (RBS) --- p.91 / Chapter 4.4 --- Other characterization techniques --- p.93 / Chapter 4.4.1 --- Thickness measurement --- p.93 / Chapter 4.4.2 --- Measurement of Tc in YBCO --- p.93 / Chapter 4.4.3 --- Thermomechanical analysis system (TMS) --- p.95 / Chapter 4.4.4 --- Differential scanning calorimeter (DSC) --- p.98 / Chapter Chapter 5 --- Epitaxial films --- p.99 / Chapter 5. 1 --- YBCO films --- p.99 / Chapter 5.1.1 --- YBCO on sapphire --- p.99 / Chapter 5.1.2 --- YBCO on spinel (MgAl2O4) --- p.115 / Chapter 5.1.3 --- YBC0//SrTi〇3//spinel --- p.130 / Chapter 5.1.4. --- YBCO on Mg〇 --- p.134 / Chapter 5.1.5 --- YBCO on SrTi〇3(110) --- p.143 / Chapter 5.2 --- PZT films --- p.182 / Chapter 5.2.1 --- PZT on MgO --- p.182 / Chapter 5.2.2 --- PZT on spinel --- p.188 / Chapter 5.2.3 --- High temperature structural transition of PZT films --- p.195 / Chapter Chapter 6 --- Conclusion --- p.218 / REFERENCES --- p.220
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study of chemical and electronic properties of silicon nitride and silicon oxynitride thin films =: 氮化硅與氮氧化硅薄膜的化學與電子性質的硏究. / 氮化硅與氮氧化硅薄的化學與電子性質的硏究 / The study of chemical and electronic properties of silicon nitride and silicon oxynitride thin films =: Dan hua gui yu dan yang hua gui bo mo de hua xue yu dian zi xing zhi de yan jiu. / Dan hua gui you dan yang hua gui bo mo de hua xue you dian zi xing zhi de yan jiuJanuary 1999 (has links)
by Yun-hung Ng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / by Yun-hung Ng. / Abstract --- p.ii / 論文摘要 --- p.iii / Acknowledgements --- p.iv / Table of Contents --- p.v / List of Figures --- p.ix / List of Tables --- p.xi / Chapter Chapter 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Background of Study --- p.1 / Chapter 1.2 --- General Properties of a-SiNx and a-SiOxNy --- p.1 / Chapter 1.3 --- Common Preparation Methods of a-SiNx and a-SiOxNy --- p.2 / Chapter 1.4 --- Applications of a-SiNx in Microelectronics --- p.4 / Chapter 1.5 --- Applications of a-SiOxNy in Microelectronics --- p.6 / References --- p.8 / Chapter Chapter 2 --- METHODOLOGY --- p.10 / Chapter 2.1 --- Introduction --- p.10 / Chapter 2.2 --- Mott Rule --- p.10 / Chapter 2.3 --- Random Mixture Model --- p.11 / Chapter 2.4 --- Random Bonding Model --- p.12 / Chapter 2.5 --- Hasegawa Model --- p.15 / References --- p.20 / Chapter Chapter 3 --- INSTRUMENTATION --- p.21 / Chapter 3.1 --- X-ray Photoelectron Spectroscopy (XPS) --- p.21 / Chapter 3.1.1 --- Fundamental Theory of XPS --- p.21 / Chapter 3.1.2 --- Qualitative Analysis using XPS --- p.25 / Chapter 3.1.2.1 --- Chemical Shift --- p.25 / Chapter 3.1.2.2 --- Angular Effect on XPS --- p.28 / Chapter 3.1.2.3 --- Valence Band Investigation --- p.28 / Chapter 3.1.3 --- Quantitative Analysis using XPS --- p.30 / Chapter 3.1.4 --- Instrumental Setup of XPS --- p.33 / Chapter 3.2 --- Ultraviolet Photoelectron Spectroscopy --- p.37 / Chapter 3.2.1 --- Basic Theory of UPS --- p.37 / Chapter 3.2.2 --- Instrumentation --- p.38 / References --- p.41 / Chapter Chapter 4 --- SHORT RANGE ORDER OF a-SiNx --- p.42 / Chapter 4.1 --- Sample Preparation --- p.42 / Chapter 4.2 --- XPS Analysis of a-SiNx --- p.43 / Chapter 4.2.1 --- Angle Resolved XPS Analysis --- p.43 / Chapter 4.2.2 --- RB Model and RM Model Simulation of a-SiNx --- p.43 / Chapter 4.2.3 --- Intermediate Mixture (IM) Model --- p.50 / Chapter 4.2.4 --- Valence Band Structure of a-SiNx --- p.51 / Chapter 4.3 --- Raman Measurements --- p.54 / Chapter 4.4 --- Photoluminescence of a-SiNx --- p.54 / Chapter 4.5 --- Large Scale Potential Fluctuations in a-SiNx --- p.56 / Chapter 4.6 --- Conclusion --- p.61 / References --- p.62 / Chapter Chapter 5 --- MOTT RULE VERIFICATION OF a-SiOxNy --- p.65 / Chapter 5.1 --- Sample Preparation --- p.65 / Chapter 5.2 --- Validity of Mott Rule on a-SiOxNy --- p.66 / Chapter 5.3 --- Conclusion --- p.73 / References --- p.74 / Chapter Chapter 6 --- SHORT RANGE ORDER OF a-SiOxNy --- p.75 / Chapter 6.1 --- Angle Resolved XPS Analysis --- p.75 / Chapter 6.2 --- Random Bonding Model Simulation of a-SiOxNy --- p.75 / Chapter 6.3 --- Conclusion --- p.79 / References --- p.82 / Chapter Chapter 7 --- CONCLUSIONS --- p.83
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Epitaxial growth of La-Ca-Mn-O thin films with ultra-sharp metal-insulator transition =: 外延生長金屬--絶緣轉變非常明顯的La-Ca-Mn-薄膜. / 外延生長金屬--絶緣轉變非常明顯的La-Ca-Mn-O薄膜 / Epitaxial growth of La-Ca-Mn-O thin films with ultra-sharp metal-insulator transition =: Wai yan sheng chang jin shu--jue yuan zhuan bian fei chang ming xian de La-Ca-Mn-O bo mo. / Wai yan sheng chang jin shu--jue yuan zhuan bian fei chang ming xian de La-Ca-Mn-O bo moJanuary 1999 (has links)
by Leung Chi Hung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / by Leung Chi Hung. / Acknowledgments --- p.i / Abstract --- p.ii-iii / Table of Contents --- p.iv-v / Figures Caption --- p.vi-xii / Tables Caption --- p.xiii / Chapter 1. --- Introduction / Chapter 1.1 --- "Magnetoresistance (MR),Giant Magnetoresistance (GMR),Colossal Magnetoresistance (CMR) and Their Applications" --- p.1-1 / Chapter 1.2 --- Colossalmagnetoresistance Effect in LCMO --- p.1-5 / Chapter 1.3 --- Significance of Ultra-Sharp Metal-Semiconductor Transition LCMO Thin Film --- p.1-12 / Chapter 1.4 --- The Use of Silver in the YBCO --- p.1-14 / Chapter 1.5 --- Previews --- p.1-15 / Chapter 1.6 --- References --- p.1-17 / Chapter 2. --- Epitixial Growth of Single-Crystal LCMO Thin Film by FTS method / Chapter 2.1 --- Facing-Target Sputtering Method --- p.2-1 / Chapter 2.2 --- Fabrication of LCMO Targets --- p.2-4 / Chapter 2.3 --- Deposition of the LCMO Thin Film / Chapter 2.3.1 --- Deposition Condition --- p.2-6 / Chapter 2.3.2 --- Deposition Process --- p.2-9 / Chapter 2.4 --- X-ray Diffraction Studies and Surface Morphology --- p.2-11 / Chapter 2.5 --- M-S Transition of LCMO Thm Film --- p.2-15 / Chapter 2.6 --- Discussions --- p.2-19 / Chapter 3. --- The Role of Silver in LCMO / Chapter 3.1 --- Reaction between Ag and LCMO --- p.3-1 / Chapter 3.2 --- Grain Size and Transition Temperature in Bulk LCMO --- p.3-9 / Chapter 3.3 --- Improving the Sharpness of Metal - Semiconductor Transition and Crystallinity of LCMO Film --- p.3-15 / Chapter 3.4 --- Stabilization of the LCMO Structure --- p.3-21 / Chapter 3.5 --- Discussions --- p.3-25 / Chapter 4 --- Epitaxial Growth of the Ultra-Sharp Metal-Semiconductor Transition LCMO Thin Film / Chapter 4.1 --- Synthesis Process of the Ultra-Sharp Metal-Semiconductor Transition LCMO Thin Films --- p.4-1 / Chapter 4.2 --- Resistivity and Magnetoresistance --- p.4-6 / Chapter 4.3 --- Thermal Annealing Effects / Chapter 4.3.1 --- Oxygen Annealing Effect --- p.4-15 / Chapter 4.3.1 --- High Pressure Annealing Effect --- p.4-20 / Chapter 4.3.2 --- Vacuum Annealing Effect --- p.4-23 / Chapter 4.4 --- Surface Morphology and Characterization --- p.4-27 / Chapter 4.5 --- Discussions --- p.4-37
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Pressure effects on the transport properties of La₀.₆₇Ca₀.₃₃MnO₃ thin films. / 壓力對La₀.₆₇Ca₀.₃₃MnO₃薄膜的導電能的效應 / Pressure effects on the transport properties of La₀.₆₇Ca₀.₃₃MnO₃ thin films. / Ya li dui La₀.₆₇Ca₀.₃₃MnO₃ bo mo de dao dian neng de xiao yingJanuary 2001 (has links)
by Chan Hing Nam = 壓力對La₀.₆₇Ca₀.₃₃MnO₃薄膜的導電能的效應 / 陳慶楠. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / by Chan Hing Nam = Ya li dui La₀.₆₇Ca₀.₃₃MnO₃ bo mo de dao dian neng de xiao ying / Chen Qingnan. / Acknowledgements --- p.i / Abstract --- p.ii / 論文摘要 --- p.iii / Table of contents --- p.iv / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Introduction to colossal magnetoresistance --- p.1-1 / Chapter 1.2 --- Effects of chemical pressure and strain on LCMO thin films --- p.1-7 / Chapter 1.3 --- Review of pressure effects on bulk LCMO --- p.1-11 / Chapter Chapter 2 --- Instrumentation and Characterization / Chapter 2.1 --- Preparation of LCMO thin films --- p.2-1 / Chapter 2.2 --- X-ray diffraction (XRD) --- p.2-3 / Chapter 2.3 --- Self-clamping pressure cell --- p.2-5 / Chapter 2.3.1 --- Electrical feedthroughs --- p.2-5 / Chapter 2.3.2 --- Teflon cell --- p.2-8 / Chapter 2.3.3 --- Pressure variations in the pressure-transmitting medium --- p.2-9 / Chapter Chapter 3 --- Pressure effect on LCMO thin films grown on different substrates / Chapter 3.1 --- Annealing effect --- p.3-1 / Chapter 3.2 --- Thickness effect --- p.3-4 / Chapter 3.3 --- Lattice effect and pressure effect --- p.3-5 / Chapter 3.4 --- Crystallinity effect --- p.3-13 / Chapter Chapter 4 --- Activation energy of small polaron in LCMO thin films / Chapter 4.1 --- Motivation --- p.4-1 / Chapter 4.2 --- Basic theory --- p.4-2 / Chapter 4.3 --- Activation energy --- p.4-4 / Chapter Chapter 5 --- Conclusion --- p.5-1
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Thickness and vacuum annealing effects in single-crystal La₀.₆₇Ca₀.₃₃MnO3 thin films. / 厚度和眞空熱處理對單晶 La0.67Ca0.33 薄膜特性之影響 / Thickness and vacuum annealing effects in single-crystal La0.67₆₇Ca₀.₃₃MnO₃ thin films. / Hou du he zhen kong re chu li dui dan jing La0.67Ca0.33 bo mo te xing zhi ying xiangJanuary 2000 (has links)
Yeung Chun Fai = 厚度和眞空熱處理對單晶 La0.67Ca0.33MnO3 薄膜特性之影響 / 楊進輝. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / by Yeung Chun Fai = Hou du he zhen kong re chu li dui dan jing La0.67Ca0.33MnO3 bo mo te xing zhi ying xiang / Yang Jinhui. / Acknowledgements --- p.i / Abstract --- p.ii / 論文摘要 --- p.iv / Table of contents --- p.v / List of Figures --- p.viii / List of Tables --- p.xiii / Chapter Chapter I --- Introduction / Chapter 1.1 --- Development of magnetoresistance materials --- p.1-1 / Chapter 1.1.1 --- Magnetoresistance (MR) --- p.1-1 / Chapter 1.1.2 --- Anisotropy magnetoresistance (AMR) --- p.1-1 / Chapter 1.1.3 --- Giant magnetoresistance (GMR) --- p.1-2 / Chapter 1.1.4 --- Colossal magnetoresistance (CMR) in rare-earth manganites --- p.1-3 / Chapter 1.1.5 --- Possible origin of CMR in rare-earth manganites --- p.1-4 / Chapter 1.1.5.1 --- Double exchange mechanism --- p.1-4 / Chapter 1.1.5.2 --- Jahn-teller effect --- p.1-6 / Chapter 1.1.5.3 --- Other mechanisms --- p.1-7 / Chapter 1.1.6 --- Possible origins of CMR in Thallium manganite pyrochlores (TI2Mn207) --- p.1-7 / Chapter 1.2 --- New developments in manganite materials --- p.1-8 / Chapter 1.3 --- Our approach --- p.1-8 / Chapter 1.3.1 --- Why choose La0 .67Ca0.33Mn03 material? --- p.1-8 / Chapter 1.3.2 --- The role of oxygen content in manganite materials --- p.1-9 / Chapter 1.4 --- The scope of this thesis work --- p.1-11 / References --- p.1-12 / Chapter Chapter II --- Instrumentation / Chapter 2.1 --- Thin film deposition --- p.2-1 / Chapter 2.1.1 --- Introduction --- p.2-1 / Chapter 2.1.2 --- Facing-target sputtering (FTS) --- p.2-3 / Chapter 2.1.3 --- Deposition profile calculation for sputtering with FTS --- p.2-4 / Chapter 2.1.4 --- Vacuum system --- p.2-7 / Chapter 2.2 --- Characterization --- p.2-8 / Chapter 2.2.1 --- Profilometer --- p.2-8 / Chapter 2.2.2 --- Atomic force microscopy (AFM) --- p.2-8 / Chapter 2.2.3 --- X-ray diffraction (XRD) --- p.2-8 / Chapter 2.2.4 --- Resistance and magnetoresistance measurement --- p.2-10 / Chapter 2.2.5 --- Hall effect measurement --- p.2-11 / References --- p.2-13 / Chapter Chapter III --- Epitaxial growth of La0.67Ca0.33 Mn03 thin films / Chapter 3.1 --- Introduction --- p.3-1 / Chapter 3.2 --- Fabrication and characteristics of LCMO target --- p.3-1 / Chapter 3.3 --- Substrate materials --- p.3-5 / Chapter 3.4 --- Deposition --- p.3-10 / Chapter 3.4.1 --- Sample preparation --- p.3-10 / Chapter 3.4.2 --- Substrate temperature --- p.3-10 / Chapter 3.4.3 --- Deposition process --- p.3-17 / Chapter 3.5 --- Post-annealing effect --- p.3-18 / Chapter 3.6 --- Film composition analysis --- p.3-22 / Chapter 3.7 --- Epitaxial growth examination --- p.3-22 / References --- p.3-27 / Chapter Chapter IV --- Thickness effect in single-crystal LCMO thin films grown on NGO and STO / Chapter 4.1 --- Motivation --- p.4-1 / Chapter 4.2 --- Resistance measurement --- p.4-2 / Chapter 4.3 --- Magnetoresistance (MR) --- p.4-8 / Chapter 4.4 --- Crystal structure --- p.4-12 / Chapter 4.5 --- Surface morphology --- p.4-16 / Chapter 4.6 --- Hall effect measurement --- p.4-19 / Chapter 4.6.1 --- Basic principle --- p.4-19 / Chapter 4.6.2 --- Experiment --- p.4-20 / Chapter 4.6.3 --- Carrier concentration & mobility --- p.4-20 / Chapter 4.7 --- Discussions --- p.4-25 / References --- p.4-27 / Chapter Chapter V --- Strain dependent vacuum annealing effectin single-crystal La0.67Ga0.33MnO3 thin films / Chapter 5.1 --- Motivation --- p.5-1 / Chapter 5.2 --- Sample description --- p.5-1 / Chapter 5.3 --- Vacuum annealing process --- p.5-2 / Chapter 5.4 --- Crystal structure --- p.5-2 / Chapter 5.5 --- Resistance measurement --- p.5-6 / Chapter 5.6 --- Discussions --- p.5-8 / Chapter 5.6.1 --- Lattice expansion --- p.5-8 / Chapter 5.6.2 --- Determination of oxygen content --- p.5-9 / References --- p.5-11 / Chapter Chapter VI --- Activation energy of small polaron in La0.67Ca0.33MnO3 thin films / Chapter 6.1 --- Motivation --- p.6-1 / Chapter 6.2 --- Basic theory --- p.6-1 / Chapter 6.2.1 --- Variable range hopping --- p.6-1 / Chapter 6.2.2 --- Semiconduction --- p.6-2 / Chapter 6.2.3 --- Nearest-neighbor hoping of small polarons --- p.6-2 / Chapter 6.3 --- Sample description --- p.6-3 / Chapter 6.4 --- Resistance measurement --- p.6-4 / Chapter 6.5 --- Activation energy --- p.6-4 / Chapter 6.6 --- Discussions --- p.6-5 / References --- p.6-12 / Chapter Chapter VII --- Conclusions --- p.7-1
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