Interfacial failure Analysis of CdZnTe detectors by Scanning Acoustic Microscopy and Auger Electron Spectrum

The contacts of CdZnTe detectors are rather complicated in their structure and the common failures or instabilities observed depend largely on the quality of the contacts. However, few works has been reported on the failure analysis of the interfacial layers between the contact and CdZnTe surface. In this paper, scanning acoustic microscopy (SAM) has been adopted to characterize these contact layers. By measuring the acoustic signal at various points of contacted samples, information on the surface uniformity can be obtained. These measurements have also been complemented by Auger electron spectrum (AES) measurements, giving the chemical distribution in the near-surface region of the elements of interest