1.55μmSi_(1-x)Ge_x/Si光开关与光探测器集成的分析及设计

对１．５５μｍ波长的Ｓｉ１－ｘＧｅｘ光波导开关和Ｓｉ１－ｘＧｅｘ／Ｓｉ红外探测器的集成结构进行了系统的理论分析和优化设计。设计结果为：（１）对Ｓｉ１－ｘＧｅｘ光开关，Ｇｅ含量ｘ＝０．０５，波导的内脊高、脊宽和腐蚀深度分别为３，８．５和２．６μｍ，分支角为５～６°。要实现对１．５５μｍ波长光的开关作用，ｐｎ＋结上所需加的正向偏压值应为０．９７Ｖ；（２）对Ｓｉ１－ｘＧｅｘ／Ｓｉ探测器，Ｇｅ含量ｘ＝０．５，探测器由２３个周期的６ｎｍＳｉ０．５Ｇｅ０．５和１７ｎｍＳｉ交替组成厚度为５５０ｎｍ，长度约为１．５～２ｍｍ的超晶格，内量子效率达８０％以上。

Analysis and Design of Optical Switch and Superlattices Photodetector Combination in Si 1-x Ge x/Si for 1.55 μm Operation

A systematic analysis and optimum design have been reported for the integration of the Si1-xGex optical switch and the Si1-xGex/Si infrared detector at λ=1.55 μm. The optimizing design results are:(1) For the Si1-xGex optical switch,Ge content x=0.05. Waveguide height,width and etched depth are 3, 8.5 and 2.6 μm, respectively, branch angles are 5～6°, and the bias voltage of pn+ junction is 0.97 V.(2) For the Si1-xGex/Si infrared detector, Ge content x=0.5. Total thickness of the detector is 550 nm, shich consists of 23 periods alternate 6 nm Si0.5Ge0.5 +17 nm Si. The length of the detector is about 1.5～2 mm. The results show that the internal quantum effciency of the detector of this structure can be as high as 80%.