V-I characteristics of X-ray conductivity and UV photoconductivity of ZnSe crystals

Abstract

This article outlines the resulting experimental V-I curves for high resistance ZnSe single crystals at temperatures of 8, 85, 295, and 420 K under three intensities of X-ray and UV excitations (hvUV > Eg). This paper considers the major factors that affect the nonlinearity in the V-I curves of high resistance ZnSe. We observe superlinear dependences at low temperatures, shifting to sublinear at room temperature and above. However, at all temperatures, we have initial linear areas of V-I curves. Using the initial linear areas of these characteristics, we obtained the lifetime values of free electrons and their mobility. The comparison of the conductivity values of X-ray and UV excitations made it possible to reveal the fact that most of the electron-hole pairs recombine in the local generation area, creating a scintillation pulse, while not participating in the conductivity. When analyzing the nonlinearity of the V-I curve, two new processes were considered in the first approximation: an increase in the average thermal velocity of electrons under the action of the electric field and the selectivity of the velocity direction of the electron upon delocalization from the traps under the Poole-Frenkel effect. It is assumed that the observed nonlinearity is due to the photoinduced contact difference in potentials.

Light Sum Accumulation in ZnSe Crystals at X-Ray Excitation

“…It is confirmed experimentally by the dose dependencies of the luminescence at low temperatures [20]. It also means that not all generated free charge carriers are involved in the conductivity and localization on deep traps [23,24].…”

The Dependencies of X-Ray Conductivity and X-Ray Luminescence of ZnSe Crystals on the Excitation Intensity

“…The results of the X-ray and UV excitation of luminescence and conductivity of ZnSe crystals [37] pave the way to study zinc selenide as semiconductor detectors of ionizing radiation for the detection of ionizing radiation.…”