论文部分内容阅读
在“Y”型光纤一个端面上垂直放置涂有透明薄膜的基片 ,入射光在光纤—薄膜层—空气的界面处两次反射 ,由于两束反射光之间存在光程差 ,所以反射光发生干涉。不需要测量干涉条纹 ,仅通过对反射光谱的分析计算 ,可以测出薄膜的厚度以及折射率的数值。在单晶硅基片上做非晶的PSiO2 膜的甩膜实验中使用该方法测试PSiO2 膜的厚度 ,实验证明 ,该方法测量精度高、速度快 ,对薄膜无破坏作用。用卤素白光和红光的准单色光( 60 0nm～ 860nm)作为光源 ,膜厚范围为 0 5到几十微米 ,测量误差小于 4 0nm。进行了实验验证 ,给出了对噪声的处理方法
A substrate coated with a transparent film is placed vertically on one end of a “Y” type optical fiber. The incident light is reflected twice at the interface of the optical fiber and the film layer. Due to the optical path difference between the two reflected lights, the reflected light Intervention occurred. Without the need to measure interference fringes, the thickness of the film and the value of the refractive index can be measured only by analyzing and calculating the reflection spectrum. This method was used to test the thickness of PSiO2 film on the mono-crystalline silicon substrate. The experiment shows that this method has the advantages of high precision, high speed and no damage to the film. With white light and red light of the quasi-monochromatic light (60 0nm ~ 860nm) as a light source, the film thickness range of 0 5 to several tens of microns, the measurement error is less than 400nm. The experimental verification is given, and the method to deal with noise is given