Lo Kwok Wing. / Thesis submitted in: November 2003. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 95-98). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.ii / Table of Contents --- p.iii / List of Figures --- p.iv / List of Tables --- p.v / Chapter iii. --- Table of Contents / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Magnetic CoPt and FePt Alloys --- p.1 / Chapter 1.1.2 --- Crystal Structures --- p.2 / Chapter 1.1.3 --- Magnetic Properties --- p.5 / Chapter 1.2 --- Magnetic Nanocomposite Films --- p.6 / Chapter 1.2.1 --- Ferromagnetic CoPt & FePt Alloy Nanoparticles --- p.7 / Chapter 1.3 --- Preparation Methods of CoPt & FePt Nanocomposite Films --- p.8 / Chapter 1.4 --- Aim and Motivation of this Research Project --- p.9 / Chapter Chapter 2 --- Sample Preparation and Characterization Techniques --- p.11 / Chapter 2.1 --- Sample Preparation --- p.11 / Chapter 2.1.1 --- Metal Vapor Vacuum Arc (MEVVA) Implantation System --- p.11 / Chapter 2.1.2 --- Preparation Procedures --- p.13 / Chapter 2.2 --- Characterization Techniques --- p.18 / Chapter 2.2.1 --- Rutherford Backscattering Spectroscopy (RBS) --- p.18 / Chapter 2.2.2 --- X-ray Diffractometry (XRD) --- p.20 / Chapter 2.2.3 --- Atomic Force Microscopy (AFM) --- p.23 / Chapter 2.2.4 --- Vibrating Sample Magnetometry (VSM) --- p.24 / Chapter Chapter 3 --- Characterization of Co and CoPt Implanted Samples --- p.28 / Chapter 3.1 --- Composition of Implanted Samples --- p.28 / Chapter 3.2 --- Phase Evolution and Crystal Structures --- p.34 / Chapter 3.2.1 --- Phase Evolution with Annealing Temperature --- p.35 / Chapter 3.2.2 --- Grain Size of Implanted Samples --- p.37 / Chapter 3.3 --- Magnetic Properties --- p.37 / Chapter 3.3.1 --- Dependence of Hc on Film Compositions --- p.39 / Chapter 3.3.2 --- Dependence of Hc on annealing Temperature --- p.42 / Chapter Chapter 4 --- Characterization of Fe and FePt Implanted Samples --- p.44 / Chapter 4.1 --- Overview --- p.44 / Chapter 4.2 --- Low Dose Implanted Samples --- p.44 / Chapter 4.2.1 --- RBS --- p.44 / Chapter 4.2.2 --- Phase Formation and Crystal Structures --- p.48 / Chapter 4.2.2-1 --- Phase Evolution with Annealing Temperature --- p.49 / Chapter 4.2.3 --- Grain Size of Implanted Samples --- p.51 / Chapter 4.2.4 --- AFM Results --- p.53 / Chapter 4.2.5 --- Magnetic Properties --- p.55 / Chapter 4.2.5-1 --- M-H Characteristics --- p.55 / Chapter 4.2.5-2 --- Coercivity Against Annealing Temperature --- p.55 / Chapter 4.3 --- High Dose Implanted Samples --- p.61 / Chapter 4.3.1 --- RBS --- p.62 / Chapter 4.3.2 --- Phase Formation and Crystal Structures --- p.66 / Chapter 4.3.2-1 --- Phase Evolution with Annealing Temperature --- p.67 / Chapter 4.3.2-2 --- Grain Size of Implanted Samples --- p.70 / Chapter 4.3.3 --- Magnetic Properties --- p.72 / Chapter 4.3.3-1 --- M-H Characteristics --- p.73 / Chapter 4.3.3-2 --- Coercivity Against Annealing Temperature --- p.74 / Chapter 4.3.3-3 --- Low Temperature Measurements --- p.79 / Chapter 4.3.3-4 --- Coercivity against annealing time --- p.79 / Chapter 4.3.4 --- Microstructure --- p.84 / Conclusion --- p.88 / Appendices --- p.90 / Bibliolography --- p.95 / Publications --- p.98

Wang Juan = 納米金顆粒與氧化鋁複合物薄膜光學吸收譜中的尺寸和濃度效應 / 王娟. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 55-58). / Text in English; abstracts in English and Chinese. / Wang Juan = Na mi jin ke li yu yang hua lv fu he wu bo mo guang xue xi shou pu zhong de chi cun he nong du xiao ying / Wang Juan. / Abstract --- p.i / 摘要 --- p.ii / Acknowledgment --- p.iii / Table of contents --- p.iv / List of Figures --- p.vii / List of Tables --- p.ix / Chapter CHAPTER 1: --- Introduction --- p.1 / Chapter CHAPTER 2: --- Background --- p.3 / Chapter 2.1 --- Optical response of metal-particle/matrix composite system in an electronic field --- p.3 / Chapter 2.1.1 --- The concept of plasmon and the dielectric function of metal particle --- p.3 / Chapter 2.1.2 --- The concept of surface plasmon resonance --- p.4 / Chapter 2.2 --- The theories describing the optical absorption properties of metal particle/matrix composite system --- p.5 / Chapter 2.2.1 --- The Mie theory --- p.5 / Chapter 2.2.2 --- The Maxwell-Garnett (M.G.) effective medium theory --- p.6 / Chapter 2.3 --- Previous experimental works in the field --- p.7 / Chapter CHAPTER 3: --- Experimental and instrumentation --- p.8 / Chapter 3.1 --- Fabrication of the Au-nanoparticle /A12O3-matrix composite thin films --- p.11 / Chapter 3.1.1 --- Sputtering techniques and radio-frequency magnetron sputtering --- p.11 / Chapter 3.1.2 --- Experimental set up and the deposition process --- p.13 / Chapter 3.2 --- The chemical and structural characterizations of the films --- p.14 / Chapter 3.2.1 --- X-ray Photoelectron Spectroscopy (XPS) --- p.14 / Chapter 3.2.2 --- X-ray Diffraction (XRD) --- p.15 / Chapter 3.2.3 --- Transmission Electron Microscopy (TEM) --- p.17 / Chapter 3.3 --- The optical absorption measurement: UV spectrometer --- p.21 / Chapter CHAPTER 4: --- Results and discussions --- p.23 / Chapter 4.1 --- General description of the as-prepared samples --- p.23 / Chapter 4.1.1 --- Chemical composition of the films --- p.23 / Chapter 4.1.2 --- General microstructure of the films and the relationship between the deposition parameters --- p.25 / Chapter 4.2 --- The optical absorption: relationship between the SPR absorption and the microstructure --- p.27 / Chapter 4.2.1 --- The shifting of the surface plasmon resonance --- p.27 / Chapter 4.2.1.1 --- The size effect on the SPR frequency shifting --- p.27 / Chapter 4.2.1.2 --- The concentration effect on the SPR frequency shifting --- p.42 / Chapter 4.2.2 --- The broadening of the surface plasmon resonance: size dependence of the relaxation time of free electrons --- p.51 / Chapter CHAPTER 5: --- Conclusions --- p.53 / Appendix --- p.54 / Reference --- p.55

Strong size effects in plastic deformation of thin films have been experimentally observed, indicating non-traditional deformation mechanisms. These observations require improved understanding of the behavior of dislocation in small size materials, as they are the primary plastic deformation carrier. Dislocation dynamics (DD) is a computational method that is capable of directly simulating the motion and interaction of dislocations in crystalline materials. This provides a convenient approach to study micro plasticity in thin films. While two-dimensional dislocation dynamics simulation in thin film proved that the size effect fits Hall-Petch equation very well, there are issues related to three-dimensional size effects. In this work, three-dimensional dislocation dynamics simulations are used to study model cooper thin film deformation. Grain boundary is modeled as impenetrable obstacle to dislocation motion in this work. Both tension and cyclic loadings are applied and a wide range of size and geometry of thin films are studied. The results not only compare well with experimentally observed size effects on thin film strength, but also provide many details on dislocation processes in thin films, which could greatly help formulate new mechanisms of dislocation-based plasticity.

Zhao Kun. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese. / Zhao Kun.

by Xianting Zeng. / Publication date from spine. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 165-173). / ABSTRACT --- p.iii / ACKNOWLEDGEMENT --- p.v / TABLE OF CONTENTS --- p.vii / LIST OF FIGURES --- p.x / LIST OF TABLES --- p.xiv / Chapter I. --- Introduction --- p.1 / Chapter 1.1 --- Previous research on magnetoresistance --- p.1 / Chapter 1.2 --- Preparation methods --- p.12 / Chapter 1.3 --- Application prospects and existing problems of GMR materials --- p.15 / Chapter 1.4 --- Main contents in this thesis --- p.17 / Chapter II. --- The facing-target sputtering technique --- p.20 / Chapter 2.1 --- Brief description of FTS method --- p.20 / Chapter 2.2 --- Considerations and studies about the deposition conditions of La-Ca-Mn-O thin films --- p.26 / Chapter 2.2.1 --- Substrate materials --- p.26 / Chapter 2.2.1.1 --- Mismatch of lattice constant --- p.26 / Chapter 2.2.1.2 --- Thermal expansion coefficient --- p.31 / Chapter 2.2.1.3 --- Cleaning and surface treatment --- p.33 / Chapter 2.2.2 --- Substrate temperature --- p.35 / Chapter 2.2.3 --- Discharge pressure and sputtering power --- p.36 / Chapter 2.2.4 --- Oxygen content and critical thickness --- p.36 / Chapter 2.3 --- Fabrication and characteristics of La-Ca-Mn-O target materials --- p.42 / Chapter 3.2.1 --- Fabrication process --- p.42 / Chapter 2.3.2 --- Characterizations --- p.46 / Chapter 2.3.2.1 --- Structural parameters --- p.46 / Chapter 2.3.2.2 --- Electrical and magnetic properties --- p.51 / Chapter III. --- Growth of La-Ca-Mn-O thin films with c-axis orientation --- p.53 / Chapter 3.1 --- Thin film deposition --- p.53 / Chapter 3.2 --- Characterization methods --- p.53 / Chapter 3.2.1 --- XRD --- p.54 / Chapter 3.2.2 --- SEM/EDX --- p.54 / Chapter 3.2.3 --- VSM --- p.57 / Chapter 3.3 --- Results and discussions --- p.58 / Chapter 3.3.1 --- Structures of the films grown on (100) MgO --- p.58 / Chapter 3.3.2 --- Resistance and magnetoresistance --- p.62 / Chapter 3.3.3 --- Annealing effect --- p.69 / Chapter 3.4.3.4 --- Magnetization --- p.71 / Chapter 3.4 --- Conclusion --- p.75 / Chapter IV. --- Epitaxial growth of single crystal LCMO thin films with a-axis orientation --- p.77 / Chapter 4.1 --- Motivation and thin film deposition --- p.77 / Chapter 4.2 --- Characterizations --- p.79 / Chapter 4.2.1 --- DCD/GID --- p.79 / Chapter 4.2.2 --- Laue diffractometry --- p.84 / Chapter 4.3 --- Results and discussions --- p.85 / Chapter 4.4 --- Conclusion --- p.91 / Chapter V. --- Crystal growth mechanisms in the deposition of LCMO thin films --- p.93 / Chapter 5.1 --- Introduction --- p.93 / Chapter 5.2 --- AFM/STM --- p.96 / Chapter 5.3 --- Step-flow growth --- p.100 / Chapter 5.4 --- Roughening growth --- p.107 / Chapter 5.5 --- 3-D growth --- p.111 / Chapter 5.6 --- Conclusion --- p.119 / Chapter VI. --- Anisotropy properties of epitaxial LCMO thin films and colossal low field magnetoresistance --- p.122 / Chapter 6.1 --- Introduction --- p.122 / Chapter 6.2 --- Experiments --- p.124 / Chapter 6.3 --- Results and discussions --- p.125 / Chapter 6.3.1 --- Morphology --- p.125 / Chapter 6.3.2 --- Transport properties --- p.125 / Chapter 6.4 --- Conclusion --- p.134 / Chapter VII. --- Optical response of epitaxial LCMO thin films --- p.135 / Chapter 7.1 --- Introduction --- p.135 / Chapter 7.2 --- Experimental procedures --- p.138 / Chapter 7.2.1 --- Sample preparation --- p.138 / Chapter 7.2.2 --- Measurements of the optical spectra --- p.140 / Chapter 7.2.3 --- Measurements of the optical response --- p.140 / Chapter 7.3 --- Experimental results and discussions --- p.142 / Chapter 7.3.1 --- Optical spectra --- p.142 / Chapter 7.3.2 --- Optical response characteristics --- p.145 / Chapter 7.3.3 --- 1/f noise in LCMO materials --- p.148 / Chapter 7.4 --- Potential applications --- p.154 / Chapter 7.5 --- Conclusion --- p.156 / Chapter VIII. --- Conclusion and further studies --- p.158 / Chapter 8.1 --- Conclusion --- p.158 / Chapter 8.2 --- Further studies --- p.161 / References --- p.165

by Yueng Hiu Wa. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaf 56). / Text in English; abstracts in English and Chinese. / by Yueng Hiu Wa. / Acknowledgements --- p.i / Abstract --- p.ii / 論文摘要 --- p.iii / Table of contents --- p.iv / List of Figures --- p.v / List of Tables --- p.vi / Chapter Chapter I --- Introduction / Chapter 1.1 --- Development of magnetoresistance materials --- p.1 / Chapter 1.1.1 --- Magnetoresistance (MR) --- p.1 / Chapter 1.1.2 --- Giant magnetoresistance (GMR) --- p.1 / Chapter 1.1.3 --- Colossal magnetoresistance (CMR) in rare-earth manganites ..… --- p.4 / Chapter 1.2 --- Our research motivation --- p.5 / Chapter 1.2.1 --- Scope of this thesis --- p.7 / Chapter Chapter II --- Instrumentation / Chapter 2.1 --- Vacuum annealing system --- p.8 / Chapter 2.2 --- X-ray diffraction (XRD) --- p.11 / Chapter 2.3 --- Rutherford backscattering spectroscopy --- p.13 / Chapter Chapter III --- Oxygen diffusion / Chapter 3.1 --- Introduction --- p.15 / Chapter 3.2 --- Theory --- p.16 / Chapter 3.3 --- Experimental --- p.21 / Chapter 3.4 --- Result and discussion --- p.24 / Chapter Chapter IV --- Vacuum annealing effect in La0.67Ca0.33Mn03 thin films / Chapter 4.1 --- Introduction --- p.31 / Chapter 4.2 --- Principles of resonant RBS and ion channeling --- p.32 / Chapter 4.2.1 --- Resonant RBS and its application / Chapter 4.2.2 --- Ion channeling and its application / Chapter 4.3 --- Experimental --- p.39 / Chapter 4.4 --- Data analysis and discussion --- p.48 / Chapter 4.5 --- Conclusion --- p.50 / Chapter Chapter V --- Conclusion

by Li Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / by Li Ho. / Abstract --- p.i / 論文摘要 --- p.ii / Acknowledgements --- p.iii / Table of Contents --- p.iv / List of Figures --- p.vi / List of Tables --- p.viii / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Magnetoresistance --- p.1 / Chapter 1.1.1 --- Giant magnetoresistance (GMR) --- p.3 / Chapter 1.1.2 --- Colossal magnetoresistance (CMR) in perovskite manganites --- p.5 / Chapter 1.1.2.1 --- Perovskite-type structure --- p.5 / Chapter 1.1.2.2 --- Metal-insulator transition --- p.7 / Chapter 1.1.2.3 --- Possible origin of CMR --- p.11 / Chapter 1.2 --- Low field magnetoresistance in CMR materials --- p.12 / Chapter 1.2.1 --- Single crystal and polycrystalline perovskite manganites --- p.12 / Chapter 1.2.2 --- Manganite trilayer junctions --- p.13 / Chapter 1.2.3 --- Possible mechanism of low field MR --- p.15 / Chapter 1.3 --- Our motivation --- p.15 / Chapter 1.3.1 --- Brief review of several manganite multilayer systems --- p.16 / Chapter 1.3.2 --- Scope of this thesis work --- p.18 / Reference --- p.19 / Chapter Chapter 2 --- Preparation and characterization of manganite thin films / Chapter 2.1 --- Thin film deposition --- p.22 / Chapter 2.1.1 --- Facing-target sputtering (FTS) --- p.22 / Chapter 2.1.2 --- Vacuum system --- p.25 / Chapter 2.2 --- Fabrication and characterization of PCMO and LCMO targets --- p.27 / Chapter 2.3 --- Epitaxial growth of LCMO thin films --- p.31 / Chapter 2.3.1 --- Substrate materials --- p.31 / Chapter 2.3.2 --- Deposition conditions --- p.32 / Chapter 2.3.3 --- Deposition procedure --- p.33 / Chapter 2.3.4 --- Results and discussions --- p.34 / Chapter 2.3.4.1 --- Morphology --- p.35 / Chapter 2.3.4.2 --- Structure --- p.39 / Chapter 2.3.4.3 --- Transport properties --- p.42 / Chapter 2.3.4.4 --- Conclusion --- p.48 / Chapter 2.4 --- Epitaxial growth of PCMO thin films --- p.49 / References --- p.51 / Chapter Chapter 3 --- LCMO/PCMO multilayer / Chapter 3.1 --- Sample preparation --- p.53 / Chapter 3.2 --- Results and discussion --- p.53 / Chapter 3.2.1 --- Structure characterization --- p.55 / Chapter 3.2.2 --- Transport properties --- p.59 / Chapter 3.2.3 --- Low-field magnetoresistance --- p.55 / Chapter 3.2.4 --- Magnetization --- p.73 / Chapter 3.3 --- Conclusion --- p.76 / References --- p.77 / Chapter Chapter 4 --- Conclusions --- p.78

Made available in DSpace on 2014-06-11T19:31:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-12-05Bitstream added on 2014-06-13T20:41:14Z : No. of bitstreams: 1 lima_ec_dr_ilha.pdf: 2673140 bytes, checksum: 4fe5d64f1442666680854f09eb619017 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O sistema ferroelétrico PbZr1-xTixO3 (PZT) vem sendo amplamente estudado devido às interessantes propriedades físicas para composições próximas ao Contorno de Fases Morfotrópico (CFM). A compreensão da fenomenologia de filmes ferroelétricos está atualmente sob intensa investigação, pois o fenômeno da ferroeletricidade exibe uma dependência intrínseca com relação à dimensão das amostras. O processamento de filmes é muito importante para o desenvolvimento da miniaturização de dispositivos eletrônicos com baixo consumo de energia e baixa tensão de operação. Desta forma, os métodos químicos tem tido grande evolução com respeito à obtenção de filmes com boa homogeneidade e cristalinidade. As temperaturas de pirólise e de cristalização desempenham um papel fundamental na cristalinidade dos filmes. Devido às altas temperaturas de obtenção dos filmes produzidos com os métodos químicos, a volatilidade do óxido de chumbo no sistema PZT torna-se um problema fundamental para discussão. Esta observação evidenciou a presença de uma fase indesejada intitulada pirocloro. A resposta dielétrica e ferroelétrica dos filmes obtidos com a fase pirocloro revela uma degradação destas propriedades. Para contornar o problema várias hipóteses foram testadas a fim de encontrar um meio para supressão da fase pirocloro. Desta forma, a síntese dos filmes foi empregada de forma a estudar o desempenho do excesso de óxido de chumbo em função da temperatura de pirólise para diferentes substratos. A transformação da fase pirocloro para perovskita foi reportada em função da temperatura de pirólise. Diferentes técnicas experimentais foram utilizadas neste estudo visando mapear a estrutura cristalina de longo e curto alcance ao longo da espessura dos filmes, o stress/strain residual em torno da interface... / The system ferroelectric PbZr1-xTixO3 (PZT) has been widely studied due to interesting physical properties for compositions near the Morphotropic Phase Boundary (MPB). The understanding of the phenomenology of ferroelectric films is currently under intense investigation, because the phenomenon of ferroelectricity shows an intrinsic dependence with respect to sample size. The film processing is very important for the development of miniaturization of electronic devices with low power consumption and low voltage operation. Therefore, chemical methods have had great progress with respect to obtaining films with good homogeneity and crystallinity. The pyrolysis temperature and crystallization play a key role in the crystallinity of the films. Due to high temperatures for obtaining films with chemical methods, the volatility of lead oxide in the PZT system becomes a fundamental problem for discussion. This observation revealed the presence of an unwanted entitled pyrochlore phase. The ferroelectric and dielectric response of the films obtained with the pyrochlore phase shows a degradation of these properties. To overcome this problem several hypotheses were tested in order to find a way to suppress the pyrochlore phase. Thus, the synthesis of the films was employed in order to study the performance of the excess lead oxide as a function of pyrolysis temperature for different substrates. The transformation of pyrochlore to perovskite phase was reported as a function of pyrolysis temperature. Different experimental techniques were used in this study to map the crystal structure of long and short range along the different thicknesses of the films, the stress/strain residual around the interface film/substrate, morphology, electrical properties, piezoelectric and ferroelectric films. The integrated analysis of the results aims to understand the phenomenology associated with the origins of self-polarization in ferroelectric thin films

Orientador: Eudes Borges de Araújo / Banca: José de los Santos Guerra / Banca: Keizo Yukimitu / Banca: Antonio Sergio Bezerra Sombra / Banca: José Antonio Eiras / Resumo: O sistema ferroelétrico PbZr1-xTixO3 (PZT) vem sendo amplamente estudado devido às interessantes propriedades físicas para composições próximas ao Contorno de Fases Morfotrópico (CFM). A compreensão da fenomenologia de filmes ferroelétricos está atualmente sob intensa investigação, pois o fenômeno da ferroeletricidade exibe uma dependência intrínseca com relação à dimensão das amostras. O processamento de filmes é muito importante para o desenvolvimento da miniaturização de dispositivos eletrônicos com baixo consumo de energia e baixa tensão de operação. Desta forma, os métodos químicos tem tido grande evolução com respeito à obtenção de filmes com boa homogeneidade e cristalinidade. As temperaturas de pirólise e de cristalização desempenham um papel fundamental na cristalinidade dos filmes. Devido às altas temperaturas de obtenção dos filmes produzidos com os métodos químicos, a volatilidade do óxido de chumbo no sistema PZT torna-se um problema fundamental para discussão. Esta observação evidenciou a presença de uma fase indesejada intitulada pirocloro. A resposta dielétrica e ferroelétrica dos filmes obtidos com a fase pirocloro revela uma degradação destas propriedades. Para contornar o problema várias hipóteses foram testadas a fim de encontrar um meio para supressão da fase pirocloro. Desta forma, a síntese dos filmes foi empregada de forma a estudar o desempenho do excesso de óxido de chumbo em função da temperatura de pirólise para diferentes substratos. A transformação da fase pirocloro para perovskita foi reportada em função da temperatura de pirólise. Diferentes técnicas experimentais foram utilizadas neste estudo visando mapear a estrutura cristalina de longo e curto alcance ao longo da espessura dos filmes, o stress/strain residual em torno da interface... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The system ferroelectric PbZr1-xTixO3 (PZT) has been widely studied due to interesting physical properties for compositions near the Morphotropic Phase Boundary (MPB). The understanding of the phenomenology of ferroelectric films is currently under intense investigation, because the phenomenon of ferroelectricity shows an intrinsic dependence with respect to sample size. The film processing is very important for the development of miniaturization of electronic devices with low power consumption and low voltage operation. Therefore, chemical methods have had great progress with respect to obtaining films with good homogeneity and crystallinity. The pyrolysis temperature and crystallization play a key role in the crystallinity of the films. Due to high temperatures for obtaining films with chemical methods, the volatility of lead oxide in the PZT system becomes a fundamental problem for discussion. This observation revealed the presence of an unwanted entitled pyrochlore phase. The ferroelectric and dielectric response of the films obtained with the pyrochlore phase shows a degradation of these properties. To overcome this problem several hypotheses were tested in order to find a way to suppress the pyrochlore phase. Thus, the synthesis of the films was employed in order to study the performance of the excess lead oxide as a function of pyrolysis temperature for different substrates. The transformation of pyrochlore to perovskite phase was reported as a function of pyrolysis temperature. Different experimental techniques were used in this study to map the crystal structure of long and short range along the different thicknesses of the films, the stress/strain residual around the interface film/substrate, morphology, electrical properties, piezoelectric and ferroelectric films. The integrated analysis of the results aims to understand the phenomenology associated with the origins of self-polarization in ferroelectric thin films / Doutor

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