Determination of trapping center parameters of Tl_2Ga _2S_3Se layered crystals by thermally stimulated current measurements

摘要

We have carried out thermally stimulated current (TSC) measurements on as-grown Tl_2Ga_2S_3Se layered single crystals in the temperature range 1060 K with different heating rates of 0.61.5 K s ~1. The data were analyzed by curve fitting, initial rise, and peak shape methods. The results were in good agreement with each other. Experimental evidence was obtained for trapping center in Tl_2Ga_2S _3Se crystal with activation energy of 11 meV. The capture cross section and concentration of the traps were found to be 1.5 × 10 ~(-23) cm~2 and 1.44 × 10~(10) cm~(-3), respectively. Analysis of the TSC data at different light excitation temperatures leads to a value of 18meV/decade for the traps distribution.