ABSTRACT
Optical experiments were carried out on In-rich CuIn(Ga)Se2 thin films prepared by rapid thermal processing (RTP). The In-rich layers show a single, broad and structurless luminescence band in the spectral range from 0.8 eV to 1.05 eV. The excitation power dependence and the temperature dependence of the recombination are well described by switching over from tail-impurity recombination to band-impurity recombination in a highly compensated semiconductor. The impurity concentrations are determined to be in the 1018cm−3 range, while the carrier concentrations at room temperature are about 1016cm−3.
