Improving crystal quality of InGaAs∕GaAs quantum dots by inductively coupled Ar plasma

Abstract

The crystal quality of InGaAs∕GaAs quantum dots (QDs) is substantially improved without redistribution of composition using inductively coupled Ar plasma exposure. After plasma exposure, the QDs exhibit an increase in photoluminescence intensity by a factor of 1.7 while keeping the peak wavelength unshifted, and the band gap blueshift after rapid thermal annealing is suppressed, denoting an improvement in thermal stability. The time-resolved photoluminescence shows an increase in carrier lifetime from 735to1140ps by plasma exposure, indicating the mechanism of grown-in defects reduction in the QD regions.