采用电子束热蒸发技术制备了ZnSe薄膜, 研究了532 nm波长的不同能量(2.0 mJ、2.5 mJ、3.0 mJ)、不同脉冲数(3、10、15)激光诱导前后, ZnSe薄膜的透射率、折射率、消光系数、损伤阈值(LIDT)的变迁。研究结果显示, 在能量为2.0 mJ激光辐照后, ZnSe薄膜折射率提高, 透射率下降。相比较能量为2.5 mJ、3.0 mJ激光辐照, 在能量为2.0 mJ激光辐照后折射率提高最明显, 由2.489 4提高到2.501 6。薄膜损伤阈值从0.99 J/cm2提高到1.39 J/cm2(10脉冲辐照); 薄膜的损伤经过了无损伤到严重损伤突变的损伤演变过程。采用原子力显微镜对预处理后薄膜表面粗糙度进行检测, 发现激光预处理后的薄膜表面粗糙度Ra有所下降, 从0.563 nm降低到0.490 nm(15脉冲激光辐照)。

The ZnSe thin films were manufactured by electron beam thermal evaporation technique and the whole changes were studied in transmittance, refractive index, extinction coefficient and laser-induced damage threshold (LIDT) of ZnSe thin films under the laser induction of 532 nm wavelength in different levels of energy (2.0 mJ, 2.5 mJ, 3.0 mJ) and pulse number (3, 10, 15). The results show that after laser irradiation of 2.0 mJ, the refractive index of ZnSe increases while the transmittance decreases. Compared with the laser irradiation of 2.5 mJ and 3.0 mJ, the laser irradiation of 2.0 mJ has the most obvious refractive index increase, from 2.489 4 to 2.501 6. The damage threshold of the film also increases from 0.99 J/cm2 to 1.39 J/cm2 (10-pulse irradiation), and the damage process of the film evolves from zero damage to severe damage and mutation. Besides, the atomic force microscopy (APM) helped test the surface roughness of the preprocessed film, finding a certain drop of the average surface roughness, namely Ra, in the film with laser preprocessing, from 0.563 nm to 0.490 nm (15-pulse laser irradiation).