Scanning Photodielectric Spectroscopy of CdZnTe Crystals

An original method of scanning photodielectric spectroscopy (SPDS), which belongs to photoelectric methods for studying localized states of charge carriers in wide-gap semiconductors, is presented. A distinctive feature of this method is the possibility of measuring not only the energy spectrum of carrier states but also the near-surface electrostatic potential of the crystal. The method is based on high sensitivity measurements of the spectral dependences of the real and imaginary parts effective values of the crystal permittivity in the low-frequency region. The obtained dependencies are presented in the form of diagrams in the complex plane. Modifications of the method are considered. The main results of the SPDS study of cadmium zinc telluride crystals are presented.