Effect of localized states on the optical properties in InGaAs/GaAs multiple quantum wells grown by MOCVD

Abstract

The InGaAs/GaAs multiple quantum wells (MQWs), as the most commonly used semiconductor laser epitaxial material, have important optical properties and wide-spread applications. However, the segregation of In atoms in the InGaAs/GaAs MQWs with the high In component has always been a serious problem. In this paper, the In0.29Ga0.71As/GaAs MQWs were prepared by metal-organic chemical vapor deposition (MOCVD), and then the temperature and excitation power-dependent photoluminescence spectra of MQWs were performed and studied. In the variable temperature measurement, the position peak of PL and full width at half maxima (FWHM) showed an "S"-shaped change from 20 to 300 K. Our systematic theoretical and experimental studies were performed that the peak before 50 K was considered to be the lasering caused by the localized states which play a leading role. And the α parameter value obtained by fitting the theoretical formula was less than 1, which also proved the existence of the localized states at low temperature in the variable power measurement at a fixed temperature. Through this research, it is of great significance to comprehensively understand the radiation emission mechanism in InGaAs materials and further develop the epitaxial growth of InGaAs quantum wells, and can deepen the understanding of the luminescence properties of InGaAs quantum well materials.