Patent ID: 6455908
Filing Date: 2002-09-24
Classification: B82Y,H01L,Y02E

Abstract:
A radiation detector for detecting radiation directed into the radiation detector, the radiation detector comprising:a substrate: and a layer stack grown on the substrate, the layer stack comprising first and second photodiodes having respective first and second strain-compensating superlattice absorbing layers, each of the strain-compensating superlattice absorbing layers being substantially lattice matched to adjacent layers of the radiation detector and having an energy gap responsive to radiation energy in a corresponding spectral region and different from the energy gap of other strain-compensating superlattice absorbing layer of the radiation detector, the layer stack further comprising a transparent barrier layer between said fist and second strain-compensating superlattice absorbing layers, wherein the first and second strain-compensating superlattice absorbing layers are either n-type or p-type and the transparent barrier layer has a conductivity type opposite to that of the strain-compensating superlattice absorbing layers, whereby the first strain-compensating superlattice absorbing layer, the transparent barrier layer, and the second strain-compensating superlattice absorbing layer form either an n-p-n or p-n-p structure.