Detection and Electrical Properties of Cd 1–x Zn x Te Detectors at Elevated Temperatures

Abstract

We have studied the behavior of Cd_1–xZn_xTe detectors in the temperature range 24–70°C. The detector count rate stability and leakage currents are presented as a function of voltage, time, and temperature. Detector polarization due to bulk and surface effects leading to a decreased leakage current was observed. At 70°C, the position of the 32 keV photopeak of ¹³³Ba was stable with time. The peak position varies within only 3 keV, and the peak quality factor varied between 0.31 and 0.41, for a 24 h period of operation at a 60 V bias. The net count to total count ratio was also stable, with values varying between 0.56 and 0.59. The net count to total count ratio decreased from 0.78 at 25°C to 0.71 at 60°C. The conclusion is that Cd_1–xZn_xTe is a promising material for gamma ray detection at temperatures above room temperature.