title: Laser damage study of nodules in electron-beam-evaporated HfO2/SiO2 high reflectors.
abstract: A reactive electron beam evaporation process was used to fabricate 1.064 μm HfO2/SiO2 high reflectors. The deposition process was optimized to reduce the nodular density. Cross-sectioning of nodular defects by a focused ion-beam milling instrument showed that the nodule seeds were the residual particles on the substrate and the particulates from the silica source "splitting." After optimizing the substrate preparation procedure and the evaporation process, a low nodular density of 2.7/mm2 was achieved. The laser damage test revealed that the ejection fluences and damage growth behaviors of nodules created from deep or shallow seeds were totally different. A mechanism based on directional plasma scald was proposed to interpret observed damage growth phenomenon.
authors: Institute of Precision Optical Engineering, Department of Physics, Tongji University, Shanghai, China.
authors: Xinbin
authors: X
authors: Cheng
authors: Zhengxiang
authors: Z
authors: Shen
authors: Hongfei
authors: H
authors: Jiao
authors: Jinlong
authors: J
authors: Zhang
authors: Bin
authors: B
authors: Ma
authors: Tao
authors: T
authors: Ding
authors: Jiangtao
authors: J
authors: Lu
authors: Xiaodong
authors: X
authors: Wang
authors: Zhanshan
authors: Z
authors: Wang