Persistent photoconductivity in a bulk CdTe(Sb) semiconductor

Persistent photoconductivity (ppc) has been investigated in detail in a bulk CdTe(Sb) Semiconductor. The relaxation of ppc in CdTe(Sb) is found to follow a power_law, Ippc (t)= t –α, in temperature region 110K< T < 295 K, The parameter α as a function of temperature is obtaind. However, the ppc is observed only above 90K, that is contrast to previous reported results on most materials which exhibit PPC effects predominantly at low temperatures. Apossible mechanism is the presence of random local potential fluctuations in the sample, which strongly influence the carrier transport properties. Such fluctuations could be induced either by the compositional fluctuations or the impurity potential.