Infrared photodetectors using capacitance variation in InAs1-xSbx MIS devices

We report a demonstration of a photo-capacitive response in p-type InAs_{1- x} Sb _x metal-insulator-semiconductor (MIS) devices to normaiiy incident interband infrared radiation. Strong infrared response covering a wide spectral range from 2 μm ham has been observed at 77 K. This spectral response depends on the MBE growth composition x in the InAs_{1- x} Sb _x compound. A peak response of R_p (λλ) = 8.4 x 10⁵V/W at 5.5 μm was obtained. The performance of such an InAs_{1- x} Sb _x MIS device is relatively insensitive to material growth parameters. Thus such devices are promising for use as IR photodetectors and in arrays.