快速热退火对GaAs/AlGaAs量子阱材料结构及光学特性的影响研究

GaAs/AlGaAs Quantum Well Material is an important material to produce high-performance laser devices. However, the defects introduced during material growth and interface characteristics existing in heterogeneous interface of the material severely influence the performance of optoelectronic devices. RTA (rapid thermal annealing), fortunately, not only can recrystallize the material and improve the crystal quality of the material, but also promote the mixing of quantum well material interface to improve the structural characteristic of quantum well, tuning the band gap. Research on the impact of RTA on the the structure and optic character of GaAs/AlGaAs quantum well material indicates that when the temperature of RTA reaches 800℃, XRD shows that the crystal quality of the material and PL strength is significantly improved due to the elimination of the defects and dislocations on the interface of the material and the suppression of the non-radiative recombination caused by RTA. When the temperature of RTA reaches 900℃, XRD shows that the crystal quality of the material and PL luminescence strength are reduced because of the reduced quantum confinement effect of quantum well as mutual diffusion of Al-Ga atoms makes interface mixed. Besides, according to the calculation of the peak energy theory, the luminescence mechanism of PL peak at room temperature is obtained, and the result of peak fitting indicates that RTA leads to the blue shift of the whole PL peak and that mutual diffusion of Al-Ga atoms increases the transport energy between band gaps, which is the main cause of the blue shift of PL peak. PL mapping suggests that RTA can significantly improve the overall luminescence uniformity and overall quality of the material.