High performance antimony-doped germanium photoconductors

Abstract

We have produced two new single crystals of antimony-doped germanium that were specifically designed for far-infrared photoconductor applications. Variable-temperature Hall effect analysis shows that these materials are well suited for photoconductor use in terms of majority and minority dopant concentration. We have fabricated sample detectors from these materials and compared their performance to state-of-the-art high sensitivity gallium-doped germanium detectors under low-background and dark conditions. Test results indicate that these devices are nearly identical in sensitivity to the best Ge:Ga in terms of responsivity, detective quantum efficiency, and dark current, and may be favored in some applications that require longer wavelength spectral response.