New technique for lifetime and surface/interface recombination velocity measurement in thin semiconductor layers

A nondestructive photoluminescence (PL) method for measurement of the bulk lifetime tau and interface recombination velocity S is presented. The method is based on an exact analytical solution for the PL decay in a thin semiconductor layer, S and tau are obtained by analyzing the PL-decay response to a pulsed laser excitation for layers with different thicknesses. The decay analysis is done in the frequency domain, which improves accuracy and suppresses noise. The method is demonstrated on isotype double AlGaAs-GaAs-AlGaAs heterostructure, but it is also applicable for thin layers bounded by interfaces with different recombination velocities, such as SOI, GaAs-Si, and Si/sub 1-x/Ge/sub x/-Si systems.<
>