HfO2/SiO2增透膜激光诱导损伤形貌分析

摘要

HfO2/SiO2 antireflection films were prepared by electron beam evaporation method, and one of them was annealed. The transmittance spectra were measured. Because the absorbed water in the films was dislodged after annealing, to be compared with as-deposited sample, the spectrum of annealed sample shifted to short wavelength evidently. The laser induced damage test was carried out by the Nd:YAG laser in “S-on-1” mode. The laser-induced damage morphologies of the samples were mainly craters. The formation mechanism of the damage morphologies was discussed, and found that the damages were initiated by the absorption particles in the subsurface damage layer of substrate. The absorption particles located in the cracks and absorbed laser energy, then the cracks were opened and the craters were formed. Because of the mechanism of the laser-induced damage, annealing had no evident effect on the damage morphologies. Ripples could be observed by microscope.%用电子束蒸发法制备了HfO2/SiO2增透膜样品，并进行退火。测量未退火样品与退火样品的透射光谱，发现退火样品的光谱明显向短波方向移动，原因是退火后薄膜中的吸附水被去除。使用Nd：YAG激光器在“S-on-1”模式下对样品进行了激光诱导损伤处理。两种样品的损伤形貌均主要是损伤坑。考虑到损伤的成因是基底的亚表面微裂纹中的吸收颗粒吸收激光能量后导致裂纹扩大，最终形成损伤坑。基于这种损伤机制，退火对损伤没有明显影响。通过显微镜在损伤形貌中观察到了冲击波传输形成的波动条纹。