CDTE AND CDZNTE PIXEL DETECTORS FOR X-RAY SPECTROSCOPIC IMAGING

Cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) wide band gap semiconductors for x-ray detectors have experienced a rather rapid development in the last few years. Among the traditional x-ray detectors based on silicon (Si) and germanium (Ge), CdTe and CdZnTe detectors show higher detection efficiency at high energies and good room temperature performance and are well suited for the development of compact detection systems and pixel arrays for simultaneous measurements of photon interaction position and energy. This chapter is an introduction to the physics and the technology of CdTe and CdZnTe pixel detectors for x-ray spectroscopy and imaging. The physical properties of CdTe and CdZnTe and the device fabrication technology are presented. A detailed discussion on physical processes and signal formation in CdTe and CdZnTe pixel detectors follows the introduction. We describe the electrical, the spectroscopic and the spatial properties of different CdTe/CdZnTe pixel detector configurations. Finally, we present the performance and the test results of recently developed pixel detector prototypes designed for astrophysical applications.