On method of estimating recombination rates by analysis of time-resolved luminescence

Combined cathodoluminescence (CL) and photoluminescence (PL) studies in time resolved regime were used to characterize recombination properties of the semiconductor material. The characterization is based on new instantaneous decay time analysis [P. Strak et al., Journal of Alloys and Compounds 823, 153791 (2020)]. The investigation provided detailed picture of the deexcitation processes in GaN bulk layer close to the surface. The studies, based on different type of excitation allowed to identify the difference in various recombination modes related to the presence of the semiconductor surface. Moreover, it is demonstrated that the method used allows for recombination analysis of local sub-surface semiconductor material region (CL) as well as large bulk volume (PL).