AlInGaN量子阱垒层材料的优化

Research on Optimizing Barrier Material for AlInGaN Quantum Wells

采用k.p方法理论,考虑了极化电场和自由载流子重新分布等因素,通过薛定谔方程和泊松方程自洽求解得到InGaN/AlInGaN,InGaN/GaN,InGaN/InGaN,InGaN/AlGaN量子阱导带和价带的能带结构,并由此计算了不同量子阱结构的自发发射谱.分析对比发现AlInGaN材料特有的自发极化和压电极化效应在阱垒界面处形成的极化电荷对量子阱发光特性有重要的影响.以AlInGaN为垒,优化其中各元素的组分可以减小极化电场的影响,提高量子阱自发发射谱强度.同时,综合考虑了极化电荷和势垒高度的影响,提出了具体的优化方法,并给予了物理解释.

A self-consistent solution that simultaneously satisfies the Schrbdinger equations and Poisson equation is used to calculate the band structure and gain spectra of InGaN/AIInGaN, InGaN/GaN, InGaN/InGaN, and InGaN/A1GaN. It is found that the polarized electrons on the interface of the heterostructure are the main factor limiting the optical gain. The in-tensity of the spontaneous emission spectrum can be improved if AIlnGaN, which can reduce the number of polarized elec-trons,is used as a barrier. Considering the effect of the polarized electrons and the barrier energy gap,a method is put for-ward to optimize the proportion of every element in the AIInGaN barrier,and physical explanations are given.