Processing and design techniques for InGaAs/InAlAs/InP photoFETs and MSMs

Despite the theoretical advantages of InGaAs/InAlAs/InP photoFETs for electro-optical system applications, fully optimized device structures and processing protocols have yet to be developed. We report here results from several device variations directed toward such optimization. This includes variation of HEMT channel thickness and current density, grading of the hole-blocking InGaAs/InAlAs heterojunction. A novel substrate removal process with backside illumination, and frontside and backside passivation is explored for optimized discrete components as well as integrated devices. Many of these advances are applicable to both MSM photodetectors and photoFETs; results from each are presented.<
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