Performance of Si:Ga infrared detectors under reduced background fluxes

The performance of Si:Ga detectors over a wide range of background photon fluxes covering those of the cooled space telescope as well as those of ground-based applications are investigated, and the performance of these detectors is cooled 10 micron spectrometers for ground based telescopes is predicted. In a helium-cooled space telescope NEP values as low as 3 x 10 to the -17th W Hz to the -1/2 for photometric measurements are achievable. No spontaneous spiking or increased noise after changing the operation mode, as observed on the other dope Si detectors, was seen for Si:Ga. No significant performance difference was found between detectors with transparent and transverse contacts. When used in a 10 micron broad band photometer of a large ground based telescope with a six arcsec field of view, the sensitivity is limited by the 300 K background to NEP of about 4 x 10 to the -14th W Hz to the -1/2.