Nonradiative carrier recombination in dry-etched InGaAs/GaAs air-post structures is investigated by time-resolved photoluminescence measurement. Both linearly and squarely size-dependent regions are observed in the measured carrier lifetime. It is shown that in-plane diffusivity Dr and sidewall nonradiative recombination velocity Sr can be simultaneously evaluated using a carrier diffusion model. Comparing an as-etched sample and a sample wet etched after dry etching shows that Dr as well as S r are changed by removing the subsurface layer at the sidewall by wet etching. Possible causes of this change and the mechanism determining S r are discussed.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)