利用电子束蒸发技术制备了氧化铪薄膜, 并分别用氧气氛下退火和激光预处理两种后处理方法对样品进行了处理。介绍了两种后处理工艺和相关的设备, 测试分析了样品的透过率、吸收和抗激光损伤阈值。对比了两种后处理方法对降低吸收和提高激光损伤阈值的效果, 讨论了它们的作用原理。实验结果表明,激光预处理能有效降低样品的吸收值, 提高样品的抗激光损伤阈值。采用一步法(50%初始损伤阈值)预处理后, 三倍频氧化铪薄膜的损伤阈值从13 J/cm2提升到15 J/cm2; 采用两步法(依次50%、80%初始损伤阈值)预处理后, 三倍频氧化铪薄膜的损伤阈值从13 J/cm2提升到17.5 J/cm2 , 损伤几率曲线整体向高通量区域平移。

HfO2 thin films were prepared by electron beam evaporation technique. Two kinds of post-treatment methods, anneal in oxygen and laser treatment, were employed to treat the samples under the oxygen condition. The procedures of post-treatment and corresponding treatment equipment were introduce and the optical transmittance, absorption and laser induced damage threshold of a HfO2 thin film sample at 355 nm were measured before and after the treatments. The treatment results on reducing absorption and improving the LIDT by above two post-treatment methods were compared, and their working principles were discussed. The experiments demonstrate that laser treatment decreases the sample absorption and improves the LIDT of HfO2 thin films. With one step(50% LIDT), the LIDT of the HfO2 film at 355 nm increases from 13 J/cm2 to 15 J/cm2. With two steps(50% LIDT and 80% LIDT ), the LIDT of the HfO2 film at 355 nm increases from 13 J/cm2 to 17.5 J/cm2, and the damage probability curve translates to a high flux area wholly.