【摘要】 为了研究失配应变的弛豫机理 ,利用高分辨电子显微镜 (HREM)对超高真空化学气相沉积 (U HVCVD) Si/Si Ge- OI材料横截面的完整形貌和不同层及各层之间界面区的高分辨晶格像进行观察 .发现此多层结构中存在 6 0°位错和堆垛层错 .结合 Matthews和 Blakeslee提出的临界厚度的模型和相关的研究结果对 6 0°位错组态的形成和存在原因进行了分析 .在具有帽层结构的 Si1 - x Gex 应变层靠近基体一侧的界面中仅存在单一位错 ,验证了 Gosling等人的理论预测结果更多还原

【Abstract】 Observations on cross-sectional microstructure of Si/SiGe-OI grown by ultra-h igh vacuum chemical vapor deposition are done with an electron microscope with high resolution for investigating relaxation mechanism of strain induced by misf it.The cross-sectional image of Si/SiGe-OI multi-layer structure,the lattice image of every epitaxial layer,and the interfaces of adjoining epitaxial layers are shown respectively.60° dislocations and stacking faults distributed in the multi-layer structure are found.Some related theories are applied to explain th e configuration of the defects.The reasons are discussed about formation and exi sting of 60° misfit dislocations using critical thickness model developed by Ma tthews and Blakeslee and other related investigations.The theoretical conclusion predicted by Gosling and his co-workers is proved reliable that single misfit dislocations generally lie in the interface between strained Si 1- x Ge x layer and Si substrate for a heterostructure with a capping layer thinne r than its critical thickness.更多还原