为提高940nm半导体激光器抗灾变性光学损伤(COD)能力,采用无杂质空位量子阱混杂技术制备了带有无吸收窗口的940nm GaInP/GaAsP/GaInAs半导体激光器。借助光致发光光谱分析了退火温度和介质膜厚度对GaInP/GaAsP/GaInAs单量子阱混杂的影响;通过电化学电容-电压(EC-V)方法检测了经高温退火后激光器外延片的掺杂浓度分布的变化情况。实验发现,在875℃快速热退火条件下,带有磁控溅射法制备的200nm厚的SiO2盖层样品发生蓝移达29.8nm,而电子束蒸发法制备的200nm厚TiO2样品在相同退火条件下蓝移量仅为4.3nm。两种方法分别对蓝移起到很好的促进和抑制作用。将优化后的条件用于带有窗口结构的激光器器件制备,其抗COD能力提高了1.6倍。
To improve catastrophic optical damage (COD) threshold power of 940 nm semiconductor laser, the 940 nm GaInP/GaAsP/GaInAs semiconductor laser with non-absorbing window is fabricated. The impacts of rapid thermal annealing (RTA) temperature and thickness of Si02 on intermixing are evaluated by photoluminescence spectra. The distribution of doped concentration tested by electrochemical capacitance-voltage (EC-V) method is also studied. Experimental results show that, the samples coated by sputtering method with 200-nm Si02 show 29.8-nm blueshift at 875 ~C after RTA. But the blue shift of samples coated with 200-nm TiO2 by electron beam evaporation method is only 4.3 nm, which ensures a large band gap shift in the window region and maintains original band gap in gain region simultaneously. The optimized condition is used on semiconductor lasers with non-absorption window. It is found that the COD threshold is improved by 1.6 times, and the output power has been greatly improved.