Temperature dependence of the responsivity of ZnS-based UV detectors

This work focused on the studies of the high-temperature dependence of the responsivity of ZnS, ZnSTe and ZnSSe photodiodes. It was found that in gene ral the responsivity at higher temperatures will shift to longer wavelength s because of band gap narrowing. A remarkable observation is that the near- band-edge responsivities of these diodes increase at higher temperature. We believe that this observation is attributed to the change of the density o f state distribution due to lattice expansion at high temperature and a sim plified model is used to illustrate this hypothesis. (C) 2000 Elsevier Scie nce B.V. All rights reserved.