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采用定位横断面制样的高分辨电子显微技术（ＨＲＥＭ）观察了Ｐ＋ －Ｓｉ０．６５Ｇｅ０．３５／Ｐ－Ｓｉ异质结内光发射红外探测器的微结构．该器件光敏区是由３ 层Ｐ＋ －Ｓｉ０．６５Ｇｅ０．３５和２ 层ＵＤ－Ｓｉ（未掺杂硅）组成，Ｓｉ０．６５Ｇｅ０．３５／ＵＤ－Ｓｉ层间界面不明锐，有一个由于Ｇｅ 原子不均匀扩散造成的过渡带．这个过渡带缓和了界面的失配应力，因而未观察到界面晶体缺陷和严重的晶格畸变．在光敏区边缘有呈倒三角形的缺陷区，缺陷的主要类型为层错和微孪晶．层错在（１ １１）面上，而微孪晶的厚度约为２～４晶面间距，其孪晶面为（１ １１）．非晶ＳｉＯ２ 台阶上的Ｓｉ０．６５Ｇｅ０．３５和ＵＤ－Ｓｉ层由随机形核生长的多晶组成，层面呈波浪状
The microstructure of P + -Si0.65Ge0.35 / P-Si heterojunction internal light-emitting infrared detector was observed by high resolution electron microscopy (HREM). The photosensitive area of the device is composed of three layers of P + -Si0.65Ge0.35 and two layers of UD-Si (undoped silicon). The interface between Si0.65Ge0.35 / UD-Si layers is not clear and sharp, Uniform diffusion caused by the transition zone. This transition zone alleviates the interface mismatch stress and therefore no interface crystal defects and severe lattice distortion are observed. At the edge of the photosensitive area is an inverted triangle defects, the main types of defects for the fault and micro-twins. The layer faults are on the (11 11) plane, while the micro-twins have a thickness of about 2 to 4 planes with twin planes (1 11). The Si0.65Ge0.35 and UD-Si layers on amorphous SiO2 steps consist of polycrystals grown by random nucleation with wavy