Effect of high-temperature ablation on protective coating of ZnS optical windows

While infrared （IR） hard protective film of ZnS optical window is used in high temperature environment, its optical and mechanical stabilities are the premise of the IR optical system. IR hard protective film is deposited on ZnS optical windows by chemical vapor deposition （CVD）, and ablation experiments are done to the maximum temperature the film can endure. The effects of ablation temperature on the optical and mechanical properties of the protective films are investigated by surface profiler, Fourier-transform infrared （FTIR） spectrometry, IR ellipsometer, and Metallographic microscope. It is shown that the optical and mechanical properties of ZnS hard protective film change little before 500 ℃, and film refractive index and optical thickness reduce while ablation temperature surpassing 500 ℃, forming crater-like ablation structure, which leads to the reduction of film combination significantly.     

SiO2薄膜内部短程有序微结构研究

SiO₂薄膜是重要的低折射率材料之一, 针对离子束溅射(IBS)和电子束蒸发(EB)的SiO₂薄膜, 采用红外光谱反演技术获得在400–1500 cm^-1波数内的介电常数, 通过对介电能损函数的分析获得了两种薄膜在横向和纵向光学 振动模式下的振动频率和Si–O–Si键角.研究结果表明, 在EB SiO₂薄膜短程有序范围内, SiO₄的连接方式主要是类柯石英结构、3-平面折叠环和热液石英结构的SiO₄连接方式; 在IBS SiO₂薄膜短程有序范围内, SiO₄的连接方式复杂主要是类柯石英结构、3-平面折叠环、 4-平面折叠环结构和类热液石英结构. 关键词： 2薄膜')" href="#">SiO₂薄膜 离子束溅射 电子束蒸发 短程有序