Zn杂质扩散诱导AlGaInP/GaInP量子阱混杂

杂质扩散诱导量子阱混杂技术可用于制作腔面非吸收窗口,提高大功率半导体激光器的输出功率.以Zn2As2为扩散源,采用闭管扩散方式,在550℃下对650 nm半导体激光器的外延片进行了一系列Zn杂质扩散诱导量子阱混杂的实验.实验发现,随着扩散时间从20～120 min,样品光致发光(PL)谱蓝移偏移增加,峰值波长蓝移53 nm;当扩散时间超过60 min后,样品的PL谱中不仅出现了常见的蓝移峰,同时还出现了红移峰,峰值波长红移32 nm.分析表明PL谱蓝移来自Zn扩散引起的AlGaInP/GaInP间的量子阱混杂;红移来自Zn杂质扩散对样品中Ga0.51In0.49P缓冲层的影响.还研究了扩散温度(550℃)和扩散时间对样品晶体品质的影响,并在理论上计算了AlGaInP/GaInP量子阱混杂巾的Al-Ga的互扩散系数.

AlGaInP/GaInP Quantum Well Intermixing Induced by Zinc Impurity Diffusion

Quantum well intermixing induced by impurity diffusion has been used in fabricating nonabsorbing windows in the cavity facets to improve the output power of high-power laser diodes. A series of experiments on quantum well intermixing induced by Zn impurity diffusion were done on 650 nm laser diode wafers at 550 ℃. Zn was diffused using a closed ampoule method with Zn3As2 as source material. Blue shifts of photoluminescence (PL) spectra taken on the sample increase with the increasing of diffusion time, and the maximum PL blue shift is 53 nm. When the diffusion time was above 60 min, PL red shift occurred with a PL blue shift on the samples and the maximum PL red shift is 32 nm. It is concluded that the PL blue shifts come from the inter-diffusion of Al and Ga atoms between GaInP wells and AlGaInP barrier layers, while the PL red shifts come from the Ga0.51In0.49P buffer layer, and they are both induced by the Zn impurity diffusion into the sample. Additionally, the effects of the diffusion time and temperature on the crystal quality of the sample were studied, and the Al-Ga diffusion coefficient was calculated.