HgCdTe has been shown to be the first semiconductor exhibiting single-carrier multiplication in avalanchephotodiodes (APDs) up to gain values larger than 1000 and with close to zero excess noise. These results haveopened a new windows for low-flux and versatile imaging. In this paper, we report the latest results on MWIRHgCdTe APDs manufactured at SITP. These APDs display a gain of 1000 around 10V reverse bias. The excess noisefactor is between 1.2 to 1.45 up to gain of 100, and the quantum efficiency is more than 60% from 1μm wavelengthto peak wavelength 4.2 μm. These results show that the technological processes used at SITP are well adapted toAPD manufacturing. However, at present, the dark current starts increasing significantly faster than the gain at highbias, and then the device becomes dark current noise limited. APD gain performance was successfully modeled by thesimulation of electrical characteristics used Synopsys Sentaurus based on Okuto-Crowell ionizaition coefficientmodel. Therefore, Sentaurus would be used as a powerful predictive tool for SITP technology and stress itsreproducibility and optimize the devices .
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