PHOTOCONDUCTIVITY STUDIES IN VANADIUM-DOPED CDTE AND CD1-XZNXTE

Semi-insulating Cd1-xZnxTe:V crystals, for x = 0.01, 0.04, 0.07 and 0. 10, art investigated in comparison with CdTe:V i.e. for x = 0, and wit h undoped CdTe by spectral response of steady-state photoconductivity at various temperatures, mainly in the near infrared, and by thermal d ependence of the intrinsic photoconductivity. The results, which confi rm that V is indeed the dominant carrier donor, are discussed in terms of electronic transitions for the two vanadium charge states V2+ and V3+, related to the zinc concentration. It is found that the magnitude of some of these transitions vary strongly with temperature due to a two-step photo-thermal ionization process. (C) 1998 Elsevier Science B .V. All rights reserved.