一种简单高效的制备硅纳米孔阵结构的方法*

摘要

This article presents a simple and efficient method for preparing silicon nanopit arrays structure using laser interference lithogra-phy (LIL). Highly ordered nanopit arrays in two dimensions were fabricated on 2 inch Si (001) substrate by LIL and in combination with dry etching and wet etching processes. Dot arrays were directly etched to nanopit arrays with this method, which omitted the necessary steps of metal deposition and lift off in pattern reversal process. Forming a fluorocarbon organic polymer layer on silicon surface after dry etching, which can be used as a wet etching mask, and producing a thin silicon mesa layer under the SiO2 dot arrays by slight over-etching in dry etching process, are two key steps for this method. SEM images show the uniform and controllable pit arrays were prepared; the period of the arrays is 450 nm, the length of the pit is 200-280 nm. The pit arrays are composes of square and inverted pyramids, and the four facets of the inverted pyramid correspond to four crystal planes (111) of Si substrate.%　　本文介绍了一种简单高效的制备硅纳米孔阵结构的方法.利用激光干涉光刻技术,结合干法和湿法刻蚀工艺,直接将光刻胶点阵刻蚀为硅纳米孔阵结构,省去了图形反转工艺中的金属蒸镀和光刻胶剥离等必要步骤,在2英寸的硅(001)衬底上制备了高度有序的二维纳米孔阵结构.利用干法刻蚀产生的氟碳有机聚合物作为湿法刻蚀的掩膜,以及在干法刻蚀时对样品进行轻微的过刻蚀,使 SiO2点阵图形下形成一层很薄的硅台面,是本方法的两个关键工艺步骤.扫描电子显微镜图片结果表明制备的孔阵图形大小均匀,尺寸可控,孔阵周期为450 nm,方孔大小为200-280 nm.