Low Temperature Characteristics of Solid State Detectors for Energetic X-Ray, Ion and Electron Spectrometers

The low temperature characteristics of silicon surface barrier detectors have been investigated to obtain high resolution energetic particle and x-ray measurements for spacecraft applications. Relatively simple electrical and thermal coupling techniques were implemented such that large detector array concepts are feasible. For a 50 mm2 by 1.5 mm depletion depth surface barrier detector cooled to -80°C the x-ray resolution is 800 eV FWHM using an AC coupled spacecraft instrument preamplifier. Detector system design and calibration results are presented for a spacecraft instrument using both passive radiators and thermoelectric coolers. Energy loss rates in the dead zone region are given for energetic electrons with gold and aluminum surface deposits on the detectors.