Characterization and Identification of Defects in CdTe Detectors Using Scanning Laser Transient Current Technique

Cadmium Telluride (CdTe) detectors have excellent detection efficiency for high-energy photons. However, various types of defects in the bulk impair their performance. The effect of the defects can be studied using laser Transient Current Technique. By combining the technique with raster scanning, and by utilizing various imaging techniques, the defects can be classified and their impact to the detector operation can be estimated. By varying the laser focus, power, and the detector bias, different effects can be studied. In this contribution, we study defects in CdTe pad detectors by raster scanning the detector surfaces with 660 nm and 1064 nm lasers.