In_xGa_(1-x)As/GaAs量子阱应变量对变温光致发光谱的影响  

Strain Effect on Temperature Dependent Photoluminescencefrom In_xGa_(1-x)As/GaAs Quantum Wells

作　　者：叶志成[1] 舒永春[1] 曹雪[1] 龚亮[1] 姚江宏[1] 皮彪[1] 邢晓东[1] 许京军[1] 

机构地区：[1]南开大学泰达应用物理学院弱光非线性教育部重点实验室

出　　处：《发光学报》2011年第2期164-168,共5页Chinese Journal of Luminescence

基　　金：天津应用基础研究基金(06YFJZJC01100;08JCYBJC14800);国家"863"计划(2006AA03Z413)资助项目

摘　　要：利用变温光致发光(PL)研究了In0.182Ga0.818As/GaAs应变及应变补偿量子阱在77～300 K温度范围内的发光特性。随着温度T的升高,PL峰位向低能方向移动。在应力作用下In0.182Ga0.818As/GaAs量子阱的价带顶轻空穴带和重空穴带发生了劈裂。通过理论计算推导应变随温度变化对InxGa1-xAs/GaAs量子阱带隙能量的影响。在Varshni公式基础上,引入由应力导致的带隙能量变化项ΔEg。带隙能量计算结果与实验数据吻合较好。通过不同温度下光致发光半峰全宽的变化验证了应力随温度变化对量子阱发光峰的影响。The variable-temperature photoluminescence （PL） spectra of In0.1822 Ga0.818 As/GaAs strained and strain-compensation quantum wells （QWs） were experimentally determined in the temperature range of 77 - 300 K. The PL peak positions shift to lower energies with the increasing temperature. Strain which is induced by lattice mismatch between epitaxial layer and substrate removes the degeneracy between the light-hole and heavy-hole states at the top of the valence band. A theoretical calculation was presented that takes into account the temperature-induced variations in band gap and biaxial strain to explain the PL spectra. Based on the Varshni relationship, the change of the band gap energy caused by the strain was introduced. It is the function of the temperature and the alloy composition. The calculated results are agree with the experimental data. The full-width at half-maximum （FWHM） of PL spectra of In0.182Ga0.818 As/GaAs strained three quantum wells is larger than that of strain-compensation one, and increases more quickly, which is caused by exciton-LO phonon coupling. At last, strain effect on the PL spectra was confirmed through the FWHM curve at various temperature.

关 键 词：分子束外延 INGAAS/GAAS 应变量子阱 变温光致发光 

分 类 号：O472.3[理学—半导体物理]