光子学报, 2019, 48 (7): 0731001, 网络出版: 2019-07-31
薄膜微结构的近红外透射诱导增强特性
Characteristics of Near-infrared Induced Transmission Enhancement of Thin Film Micro-structures
薄膜微结构 单点金刚石切削 纳米压印 减反射 透射增强 Thin film microstructure Single point diamond turning Nano-imprint lithography Anti-reflection Transmission enhancement
摘要
在SiNx薄膜中引入微金字塔结构, 综合利用包含界面的薄膜光学微结构的折射、衍射与干涉现象, 实现透反射的调控.通过单点金刚石切削与纳米压印、等离子体各向异性刻蚀技术相结合, 将大面积、高效率、低成本的微结构制备方法推广至光学薄膜中, 实现了多种尺寸的金字塔薄膜微结构的制备, 结构单元尺寸可以在1.5~10 μm之间进行调控.光谱特性检测结果表明, SiNx薄膜微金字塔结构阵列在近红外至长波红外波段, 表现出超宽波段的减反射特性;在0.8~2.5 μm的近红外波段, 反射率低于1.0%; 在3~5 μm的中红外波段, 反射率小于2.5%; 在10~12 μm长波红外波段, 平均反射率低于5%; 与传统的四分之一波长抗反射膜系相比, SiNx薄膜微金字塔结构阵列的减反射效果的实现, 无需膜系设计时的折射率匹配, 简化了膜系结构.研究发现SiNx薄膜微金字塔结构阵列的近红外透射诱导增强特性, 高度为2~4 μm的SiNx薄膜微金字塔结构阵列, 均在2.1μm波长处出现明显的透射诱导增强效应, 且高为4 μm, 底宽为8 μm的微金字塔结构阵列的透射增强作用最为明显, 透射率达到了96%以上.实验检测与仿真分析证明, 透射增强的位置和强度由微结构的形貌尺寸及其结构比例关系决定.
Abstract
The micropyramid structures was integrated into the silicon nitride thin film. The refraction, diffraction and interference of the thin film optical microstructures which contains interface were comprehensively utilized to realize the regulation of transmission and reflection.The preparation of micro-pyramid array in SiNx film by single-point diamond turning technology combined with nano-imprint and inductively coupled plasma etching was presented. The large-area, high-efficiency, low-cost microstructure preparation method was applied to generate thin film optical microstructures. The thin film optical micropyramid structures with different sizes were fabricated. The structural unit size could be adjusted between 1.5 μm and 10 μm. Spectral characteristics test results proved the ultra-wide band anti-reflection of the SiNx thin film optical micropyramid array during near-infrared to long wave infrared region. In the near-infrared band of 0.8~2.5 μm, the reflectivity is less than 1.0%. In the mid-infrared band of 3~5 μm, the reflectivity is less than 2.5%. In the long-wavelength infrared band of 10~12 μm, the average reflectance is less than 5%. Compared to antireflection film,the anti-reflective effect of SiNx thin film micro-pyramid structure array can be achieved without the refractive index matching in the design of the films, which simplifies the structure of the films. It is also found that the SiNx thin film micro-pyramid structure array has induced transmission enhancement characteristics at near-infrared. The SiNx thin film micro-pyramid array with a height of 2 μm to 4 μm have obvious transmission-induced enhancement effects at the wavelength of 2.1μm, and the micro-pyramid structure array with a height of 4 μm and a bottom width of 8 μm has the most obvious transmission enhancement effect, and the transmittance reaches 96% at least. The position and intensity of transmission enhancement are determined by the morphology, size and structure proportion of the micro-structure based on experimental test and simulation analysis.
葛少博, 刘卫国, 周顺, 杨鹏飞, 李世杰, 黄岳田, 孙雪平, 林大斌, 张进. 薄膜微结构的近红外透射诱导增强特性[J]. 光子学报, 2019, 48(7): 0731001. GE Shao-bo, LIU Wei-guo, ZHOU Shun, YANG Peng-fei, LI Shi-jie, HUANG Yue-tian, SUN Xue-ping, LIN Da-bin, ZHANG Jin. Characteristics of Near-infrared Induced Transmission Enhancement of Thin Film Micro-structures[J]. ACTA PHOTONICA SINICA, 2019, 48(7): 0731001.