介绍了应变SiGe层的特性,包括SiGe应变层临界厚度与Ge组分的关系,能带变窄,折射率增加以及应变SiGe层的亚稳态特性。然后从材料生长方面入手,提出了4种改善长波长锗硅光电探测器性能的方案,包括采用生长缓冲层来减小位错的方法、生长高组分表面起伏多量子阱的方法和生长Ge岛超晶格的方法,随之给出了相关的实验结果,并对这4种方案进行了分析。最后对上述内容进行小结,并对Ge量子点共振腔增强型光电探测器的应用前景进行了探讨与展望。
Characteristics of SiGe strain layers are described, including the relation between critical thickness of SiGe strain layers and Ge composition, the narrowed energy band, the increased refractive index and the metastable state of SiGe strain layers. In order to improve the performance of SiGe photodetector, four methods focused on the growth of SiGe material are put forward, such as growing buffer layers to reduce dislocation, growing high composition surface fluctuations multiple quantum well, growing Ge islands superlattice, and the experimental results are ginen. The four methods are analyzed. At last, the above contents are summarized. The underling importance of the Ge quantum dot resonant cavity enhanced photodetector is discussed and its prospects are offered.