沉积温度对LaF_3薄膜性能的影响  

Influence of deposition temperature on properties of LaF_3 coating

作　　者：余华[1] 崔云[1] 申雁鸣[1] 齐红基[1] 邵建达[1] 范正修[1] 

机构地区：[1]中国科学院上海光学精密机械研究所

出　　处：《强激光与粒子束》2007年第9期1507-1511,共5页High Power Laser and Particle Beams

基　　金：国家自然科学基金资助课题(60678004)

摘　　要：在189,255,277和321℃的沉积温度下用热舟蒸发方法制备了LaF3薄膜。通过X射线衍射(XRD)测试了薄膜的晶体结构;采用分光光度计测量了薄膜的透射光谱,并计算得到样品的折射率、消光系数和截止波长;利用光学干涉仪测试得到了薄膜的残余应力;采用三倍频Nd:YAG脉冲激光测试了薄膜的激光损伤阈值。结果表明:随沉积温度的提高,LaF3薄膜的结晶状况明显变好,晶粒尺寸逐渐变大;膜层变得更加致密,折射率变大,然而薄膜吸收变得严重,截止波段向长波漂移,同时薄膜的残余应力也增加,内应力在薄膜的残余应力中起着决定作用;薄膜的激光损伤阈值在高温制备时相对较高。LaF3 single-layer coatings were prepared by thermal boat evaporation at the deposition temperatures of 189, 255, 277 and 321 ＂C respectively. The crystal structures of the coatings were characterized by X-ray diffraction（XRD）. A spectrophotometer was employed to measure its transmittance. Moreover, refractive index, extinction coefficient and cut-off wavelength were obtained from the measured transmittance spectral curve. The residual stress was evaluated by the Stoney＇s equation and optical interferometer. Laser induce damage threshold（LIDT） was performed by a tripled Nd= YAG laser system. The results show that the crystallization status becomes better with the deposition temperature increasing. Correspondingly, the grain size also gets larger. Meanwhile, the coatings become more compact and the refractive index increases. However, the absorption of coatings seriously rises and the cut-off wavelength drifts to the long wave. In addition, the residual stress also increases and the intrinsic stress plays a determinant role in the coating. The LIDT of the coating also enhances at high temperature.

关 键 词：LaFa薄膜 沉积温度 晶体结构 折射率 残余应力 激光损伤阈值 

分 类 号：O484.4[理学—固体物理]