预应变InGaN/GaN多量子阱发光特性调控研究

Control of The Emission Properties of InGaN/GaN Multiple Quantum Wells with Prestrained InGaN Interlayer

摘要:

为了减弱InGaN/GaN量子阱内的压电极化场,在蓝紫光InGaN/GaN多量子阱激光器结构中采用了预应变InGaN插入层,通过变温电致发光和高分辨X射线衍射测量研究了预应变插入层对量子阱晶体质量和发光特性的影响。实验结果显示,常温下有预应变层的量子阱电致发光谱积分强度显著提高。模拟计算进一步表明,预应变层对量子阱内压电极化场有调制效果,有利于量子阱中的应力弛豫,可以有效减弱量子限制斯塔克效应,有助于提高量子阱的发光效率。

Abstract:

In order to reduce the strong piezoelectric field in InGaN/GaN multiple quantum wells (MQWs), the influence of the prestrained InGaN interlayer on crystal quality and the emission properties of blue-violet InGaN/GaN MQWs in LD structures was investigated by means of the electroluminescence (EL) and high resolution X-ray diffraction (HRXRD). It is observed that the integrated EL intensity is increased by inserting a prestrained InGaN interlayer at room temperature. Furthermore, theoretical simulation shows that the piezoelectric field is reduced by inserting the InGaN interlayer. Therefore, the prestrained InGaN interlayer is beneficial to release the strain of MQW layer and weaken the quantum-confined Stark effect (QCSE), leading to the improvement of the light emission efficiency of blue-violet InGaN/GaN MQW LDs.