Characterization of Optical Lifetime in Silicon-on-Insulator Wafers by Photoluminescence Decay Method

Abstract

ABSTRACTWe report observation of temporal decay of luminescence due to electron-hole condensation in silicon-on-insulator (SOI) wafers. The condensate luminescence was observable in SOI wafers under ultraviolet light excitation, because of shallow penetration depth of the light and confinement of photo-excited carriers in the top-Si layer. We found that the temporal decay of the luminescence depended on the surface/interface condition and fabrication method. These findings can be explained by the difference in the recombination process via surface, interface and defect states in the top-Si layer. We propose that the decay measurement of the condensate luminescence has great potential for characterization of SOI wafers.