高等学校化学学报2026，Vol.47Issue(6)：42-51,10.DOI:10.7503/cjcu20250338
纳米空气柱阵列-SiO2复合超材料的制备和折射率调控
Fabrication and Refractive Index Tuning of Air Nanocolumn Array-Silica Composite Metamaterials
摘要
Abstract
This study proposes and validates a novel strategy for fabricating ultra-low refractive index films based on nanostructure regulation via secondary chemical etching.Initially,Ag nanowire array-silica composite metamaterial films were prepared using multi-target magnetron co-sputtering technology.After the first-step chemical etching process to remove the metallic phase,an air-nanocolumn array-silica composite metamaterial film was constructed.However,due to the limited porosity achieved by the first etching step,the resulting refractive index could not meet the requirement for further reduction.To address this issue,this work introduces a secondary chemical etching step to enlarge the diameter of the air nanocolumns,thereby increasing the porosity and successfully obtaining a composite metamaterial with an ultra-low refractive index(<1.2).The optical properties and microstructure of the films were characterized using spectroscopic ellipsometry and scanning electron microscopy.Based on the anisotropic effective medium approximation(EMA)model,the ellipsometric parameters Ψ and Δ were fitted to establish the relationship between porosity and anisotropic refractive indices,clarifying the minimum refractive index achievable by the first etching step.The effects of secondary etching time and etchant concentration on the refractive index were systematically investigated,demonstrating that the proposed ultra-low refractive index tuning method exhibits excellent process repeatability.This enables the controllable preparation of films with an ordinary refractive index ranging from 1.367 to 1.159 and an extraordinary refractive index between 1.392 and 1.191.This research provides a new pathway for the controllable preparation of ultra-low refractive index materials,holding significant application potential in photonic devices such as automotive lenses and display panels.关键词
超材料薄膜/低折射率/纳米空气柱阵列/化学刻蚀/磁控溅射Key words
Metamaterial film/Low refractive index/Nano-air column array/Chemical etching/Magnetron sputtering分类
化学化工引用本文复制引用
刘旭,黄玉铸,刘奇,曹鸿涛..纳米空气柱阵列-SiO2复合超材料的制备和折射率调控[J].高等学校化学学报,2026,47(6):42-51,10.基金项目
浙江省尖兵科技计划项目(批准号:2024C01243(SD2))和宁波市自然科学基金(批准号:2021J201)资助.Supported by the"Pioneer"and"Leading Goose"Research and Development Program of Zhejiang Province,China[No.2024C01243(SD2)]and the Natural Science Foundation of Ningbo City,China(No.2021J201). （批准号:2024C01243(SD2）
