Effects of Gamma Irradiation on Surface Properties and Detector Properties of Hg1-xCdxTe Photoconductors

It has been suggested that surface states influence minority carrier trapping at low optical backgrounds in HgCdTe detectors. If this is the case then these detectors may be vulnerable to ionizing radiation degradation. Using photo MIS detectors as the test vehicle, it was the purpose of this study to obtain further information on the effects of surface potential on detector parameters, ard or the consequences of irradiating these devices with ionizing radiation. We conclude that surface states themselves are not responsible for trapping; however a depleted surface appears to be necessary for trapping.