一种基于Ni80Cr20薄膜的高精度中性密度滤光片的制备方法  

The manufacture of a high precision neutral density filter based on Ni80Cr20 nanofilm

作　　者：郭谟强 黄元申[1] GUO Moqiang;HUANG Yuanshen(School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093)

机构地区：[1]上海理工大学光电信息与计算机工程学院,上海200093

出　　处：《光学仪器》2021年第6期70-76,共7页Optical Instruments

基　　金：上海市自然科学基金项目(19ZR1436100)。

摘　　要：Ni80Cr20合金薄膜在可见光波段展现出很好的光学中性度。真空镀膜系统中石英晶振膜厚传感器的测量误差是导致薄膜的实际光密度值偏离设定值的主要原因。为此,提出了一种提高中性密度滤光片光密度值精度的制备方法,即采用真空镀膜结合离子束蚀刻技术,通过对镀膜和蚀刻参数的精确控制,实现对薄膜厚度的精密调控,将光密度值的相对误差控制在±2%以内,绝对误差不超过±0.01,使得薄膜的厚度调控量处于原子层尺度,满足了滤光片在高精度要求下光谱系统中的使用要求。同时验证了中性密度滤光片在离子束蚀刻微量减薄后,依旧拥有良好的光学性能和表面平整度,使得离子束轰击蚀刻薄膜技术成为一种新的且可靠的薄膜厚度微量调控方法。Ni80Cr20 alloy film shows a good neutral transmission in visible light.The quartz crystal sensor in the coating machine has a system error,which results in the actual thickness being different from the standard value.To solve this problem,a new manufacturing method for controlling film thickness of neutral density filters was proposed in this paper,which is bombarded the membrane surface with low energy ion beams.Make the relative error of optical density value is controlled within±2%,and the absolute error is not more than±0.01.The error of the thickness of the film is controlled at the atomic layer scale,which meets the requirements of the use of the filter in the spectral system with high precision.It is verified that the neutral density filter still has good optical properties and surface flatness after ion beam etching in this experiment.The technology of ion beam bombardment etching becomes a new and reliable method to control the thin film thickness.

关 键 词：中性密度滤光片 Ni80Cr20 光密度 离子束蚀刻 

分 类 号：TN253[电子电信—物理电子学]