On the verification of the simple trap model by simultaneous TL/TSC measurements

Abstract

Simultaneous detection of thermoluminescence (TL) and thermally stimulated conductivity (TSC) allows acquiring a lot of information concerning basic trapping processes in dielectrics. The values of activation energies and other trap parameters determined this way noticeably depend on the kinetic model applied. This paper shows that assuming some general conditions the TL/TSC ratio should yield a monotone decreasing function. This simple property holds for the standard model consisting of an arbitrary number of trap levels and recombination centres including also continuous distribution of traps. Counter examples considering simultaneous release of electrons and holes and temperature-dependent recombination probability are given. The later case, in some situations, could be ruled out by plotting a special test function. Thus, the TL/TSC ratio provides a test for a broad class of one-carrier trap models that are used for theoretical description of trapping and recombination phenomena.