快速热处理对应变InGaAs/GaAs单量子阱激光二极管电子发射和DX中心的影响

研究分子束外延(MBE)生长的应变In0.2Ga0.8AsGaAs折射率梯度变化异质结单量子阱激光二极管的快速热处理(RTA)效应.结果表明,RTA移除了InGaAsGaAs界面非辐射中心,提高77K光致发光效率和有源层电子发射.同时Al和Ga原子互扩散,也增加了AlGaAs波导层DX中心浓度.RTA处理后样品电流冲击老化实验证明DX中心浓度呈现出相应的增加.这表明DX中心可能是激光二极管性能退化的原因之一. 关键词： 量子阱 快速热处理 电子发射 DX中心

Effect of rapid thermal annealing on electron emission and DX centers in strained InGaAs GaAs single quantum well laser diodes

Thermal processing of strained In 0.2Ga {0.8}As/GaAs graded-index separate confinement heterostructure single quantum well laser diodes grown by molecular beam epitaxy is investigated.It is found that rapid thermal annealing can improve the 77K photoluminescence efficiency and electron emission from the active layer,due to the removal of nonradiative centers from the InGaAs/GaAs interface.Because of the interdiffusion of Al and Ga atoms,rapid thermal annealing increases simultaneously the density of DX centers in the AlGaAs graded layer.The current stressing experiments of postgrowth and annealed laser diodes are indicative of a corresponding increase in the concentration of DX centers,suggesting that DX centers may be responsible for the degradation of laser diode performance.