| The research work of this thesis was mainly supported by the sub-project one "Theory on heterogeneous materials compatibility and Key Structure & Technology Innovations for Monolithic Integrated Optoelectronic Devices"(Project No.2003CB3149001) of the major project "Basic Research on Integrated Optoelectronic Devices and Microstructure Optical Fibers with Structure and Technology Innovations for Future Advanced Optical Communications", which is the State Key Development Program for Basic Research of China (Project No.2003CB314900) , in which professor Ren Xiaomin is responsible for as a chief scientist. Additionally, part of research was also assisted by the Program for New Century Excellent Talents in University (Grand No.NCET-05-0111) .At present, optical communication technologies, which are underpinning of the information society, have pulled most research attractions. In which, WDM and All-Optical Network developing rapidly, have been the research focus for a period of time. The problem how to improve the performance of hetero semiconductor materials epitaxy growth, especially compatibility ofⅢ/Ⅴcompound semiconductor with Si, for achievement of monolithic or quasi-monolithic integration is definitely the crux of the matter.In this master's thesis, the theoretical mechanisms about hetero epitaxy growth techniques, especially EPITAXIAL LATERAL OVERGROWTH and TWO STEP METHOD, for integration of larger lattice mismatch semiconductor materials in OEIC have been studied systemically. Several experiments about the above were carried out meantime by corresponding schemes. The research results can be summarized as follows:1．Theoretical expressions of the Epitaxial Lateral Overgrowth (ELOG) rate in the Metal Organic Chemical Deposition (MOCVD) have been formulated, with respect to two separate processes: vapor phase diffusion and mask surface diffusion. On the condition of InP deposition on GaAs substrate, a parametric study was accomplished in order to determine the impact of the mask/window width to the growth rate. The model, which was calculated by Finite Element Method, revealed that the key determining factors of the growth rate are mask/window width and mask width/effective mask length. The model, which ameliorates the theoretical research of ELOG, can be also used as a prediction tool to identify the growth conditions leading to expectable growth rate.2．The model of the isotropic crystal surface evolution grown on a substrate covered by the mask material in the MOCVD environment has been set up inherited from the M Khenner's theoretical research, with respect to there physical mechanisms: crystal surface diffusion, surface deposition by the chemical potential difference across the interface and the mask surface diffusion. The model was solved by a Finite Difference Method and Euler Method. Using Matlab and Fortran API techniques, the evolution of the crystal surface could be simulated dynamically in future. This evolution model could describe the whole ELOG with the above growth rate model.3．The experimental ELOG epitaxial wafers were evaluated by the means of SEM thanks to doctor Zhou Jing. The results reveal that InP/GaAs heteroepitaxy wafer based on ELOG has been achieved.4．The GaAs/Si heteroepitaxy growth structure based on Two Step Method was achieved with LP-MOCVD thanks to Doctor Xiong Deping. The optimizing growth parameters were: buffer layer growth time is 250s, buffer layer growthtemperature is 450℃. The epi-layer thickness is 1．4μm and the DCXRDω-2θFWHM is 493．6 arcsec. |
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