PERFORMANCE OF SI(LI) DETECTORS OVER A WIDE TEMPERATURE RANGE

The properties of three Si(Li) detectors have been studied over the temperature range 8.5 to 200°K. The detectors performed as high resolution spectrometers from ≈ 50°K to temperatures determined by leakage current noise; the upper temperature limit depended on the individual detector and on the bias voltage. Best spectrometer performance was attained in the temperature range 50 to 80°K. At lower temperatures, charge collection is dominated by trapping and detrapping from shallow level traps, which have no effect operation at 77°K. These traps may be due to the primary dopant (boron) and lithium; if so, a low temperature limit for the operation of lithium drifted devices is established. © 1969.