Thermally activated capture of charge carriers into irradiation induced Si/SiO2 interface states

Deep-level transient spectroscopy (DLTS) measurements of capture cross sections of Co60 induced silicon-silicon dioxide (Si/SiO2) interface states have been performed. For the accurate analysis of measured data a new technique based on numerical solutions of the emission rate equations has been used. Computer simulations of DLTS measurements have been compared with measured data in order to extract reliable results in the case of nonexponential transients. We show that the capture cross sections are thermally activated. Together with earlier consistent results on the same kind of centers, this leads us to the conclusion that vibronic properties play important roles for the electron capture into these traps.