Infrared multispectral detection using Si/SixGe1-x quantum well infrared photodetectors

A modified p-type Si/SiGe quantum well infrared photodetector for multispec tral infrared imaging applications is demonstrated. In order to improve the detector's performances we have used a SiGe emitter and a low-temperature wet passivation process that give rise to a reduced dark current, even at r elatively high bias voltages. Multispectral photoresponse at the long, mid and short wavelength infrared atmospheric windows was observed. The respons e peaks are assigned to the various classes of intervalence band transition s in the quantum wells and in the SiGe emitter layers. (C) 2001 American In stitute of Physics.