SiO2半波覆盖层对HfO2/SiO2rn高反射膜激光损伤的影响

摘要

研究了SiO2半波覆盖层对HfO2/SiO2高反射膜1064nm激光损伤的影响，分析薄膜的激光损伤特性及图貌得出, 对于单脉冲（1-ON-1）激光损伤，SiO2半波覆盖层能提高HfO2/SiO2高反射膜的激光损伤阈值；可显著降低激光损伤程度，减小灾难性损伤发生的概率；可大幅度提高HfO2/SiO2高反射膜的抗激光损伤能力。%The laser damage of HfO2/SiO2 high reflecting coating with and without　λ/2 silica overcoat was studied in detail respectively, the damage threshold and possibility was measured by using a 1064nm longitude mode,　10ns Nd:YAG laser, the laser damage size and morphology were observed and analyzed by using a Normaski microscope, main conclusions are as follows: （1) The　λ/2 silica overcoat does affect laser damage threshold of HfO2/SiO2 high reflecting coating significantly，and increase the laser damage threshold of coating up to 1.5 times; （2)　According to laser damage morphologies, λ/2 silica overcoat can reduce the serious damage of HfO2/SiO2 high reflecting coating, and prevent catastrophic damage of the hafnia top layer; （3) For multi-shot laser,　λ/2 silica overcoat can greatly improve the stability of HfO2/SiO2 high reflector against the laser pulses after the first shot.