通过双离子束溅射方法在蓝宝石、硅衬底上制备了单层SiO2薄膜,分析了SiO2薄膜残余应力、表面形貌、微观结构以及光学性能(可见-近红外0.41.2μm和中红外35μm波段)在400℃1 000℃温度范围内的演化规律.研究结果表明:在400℃附近,SiO2薄膜残余应力存在局部极小值;SiO2薄膜光学性能的演化与膜层表面质量、内部残余应力及微观结构变化密切相关;经1 000℃高温处理后,蓝宝石窗口表面SiO2薄膜红外透射性能仍能保持很好的稳定性,且膜层表面没有出现显著的气泡、开裂等损伤形貌.该研究结果可为恶劣环境下光学窗口头罩表面薄膜系统的设计提供指导.
SiO2 films are deposited on Si and sapphire(α-Al2O3)substrates by Dual Ion beam sputtering method.The microstructure,surface morphology,residual stress and optical stability of SiO2 coating in the wavelength of 0.41.2μm and 35μm are investigated,systematically.The results indicate that the residual stress goes through a local minimum value at400℃.There is a close relationship between the optical constant and the surface conditions,residual stress,microstructure of SiO2 film.As the temperature increases up to 1 000 ℃,SiO2 film can keep well thermal stability without notable damage morphology.The result can give some guidance for designing the optical coatings used in harsh environments.