应变In_（0．20）Ga_（0．80）As／GaAs单量子阱结构的光谱研究

SPECTROSCOPIC STUDIES OF STRAINED In 0.20 Ga 0.80 As/GaAs SINGLE QUANTUM WELL

报道了用光致发光光谱、吸收光谱和光电流谱研究具有相同组分和阱宽、不同覆盖层厚度的应变Ｉｎ０．２０Ｇａ０．８０Ａｓ／ＧａＡｓ单量子阱结构的实验结果．结合理论计算，观察到ＧａＡｓ覆盖层厚度对单量子阱结构的材料质量、应力驰豫和发光淬灭机制的影响，确定了各样品的应变值和导带不连续因子Ｑｃ（为０．７０±０．０５）。

The photoluminescence(PL), absorption(AB) and in plane photocurrent(PC) spectroscopies for strained In 0.20 Ga 0.80 As/GaAs single quantum well(SQW) structures were investigated.Combined with the theoretical calculation,the influence of the GaAs cap layer thickness on the material quality,strain relaxation and luminescence quenching mechanism was observed.The strain values for each sample and the conduction band offset ratio Q c (￣0.70±0.05) were deduced.The PL generation mechanism was also discussed.