Functionalities of Cd_(1-x)Zn_xSe films deposited from a water solution in IR region of a spectrum

摘要

In the present work the features of an impurity and induced impurity photoconductivities in IR region, and also anomalous photoconduction and photochemical reaction in Cd_(1-x)Zn_xSe films are considered depending on film deposition and heat treatment (HT) modes. The formation of Cd_i-Cd_i, Zn_i-Zn_i, V_(se)-Zn_i etc. associations in Cd_(1-x)Zn_xSe films, providing occurrence of optical active electronic states, carried in an interval of energy 0.3÷0.6 eV, allows to use of these films for creation non-cooled photodetectors of IR-range. At illumination of films by λ=0.95 μm light, the anomalous photoconductivity and photomemory phenomenon were observed, connected with defects of metastable states, which concentration can be controlled by film structure, deposition and HT modes, and limits by tunnel transitions of no basic located electrons and holes between r- and s-centres. The photochemical reaction with activation energy of 0.17÷0.21 eV, was observed at illumination (by λ=1.25 μm light) of Cd_(0.8)Zn_(0.2)Se films heart treated on air during 10÷5 minutes. It represents a disintegration process of donor-acceptor pairs, consisting r-centres and Cd_i, Zn_i donors, and caused by precipitation conditions and HT.