半导体学报2011，Vol.32Issue(4)：35-38,4.DOI:10.1088/1674-4926/32/4/043003
Radial microstructure and optical properties of a porous silicon layer by pulse anodic etching*
Radial microstructure and optical properties of a porous silicon layer by pulse anodic etching*
摘要
Abstract
This paper investigates the radial refractive index and optical and physical thicknesses of porous silicon (PS) layers prepared by pulse etching by means of reflectance spectroscopy, photoluminescence spectroscopy and scanning electron microscopy (SEM). The relationship between the radial refractive index and optical thickness of the PS sample and the position away from the etched centre along the radial direction has been analyzed in detail.With the position farther away from the etched centre, the SEM image shows that the physical thickness of the PS sample decreases slowly, whereas intensely decreases from 2.48 to 1.72 μm near the edge at a distance of 58 μm. Moreover, the radial refractive index increases, indicating that the porosity becomes smaller. Meanwhile, the reflectance spectra exhibit the less intense interference oscillations, which mean that the uniformity and interface smoothness of the PS layers become worse, and the envelope curves of photoluminescence spectra exhibit a trend of blue-shift, indicating a reduction in nanocrystal dimensions. The PS micro-cavity is prepared to study the radial optical properties of the PS layer, and the results verify that the uniformity and smoothness of the PS layer in the centre are better than those at the edge.关键词
porous silicon/ radial microstructure/ optical thickness/ photoluminescenceKey words
porous silicon/ radial microstructure/ optical thickness/ photoluminescence引用本文复制引用
Long Yongfu..Radial microstructure and optical properties of a porous silicon layer by pulse anodic etching*[J].半导体学报,2011,32(4):35-38,4.基金项目
Project supported by the National Natural Science Foundation of China,and the Hunan Provincial Natural Science Foundation of China,and the Fund of the 12th Five-Year Plan for Key Construction Academic Subject (Optics) of Hunan Province,China. （Optics）
