Fabrication of black silicon anti-reflection via nanocatalytic wet-chemical etch

• Published in: Molecular Crystals and Liquid Crystals Vol. 644; no. 1; pp. 169 - 174
• Main Authors: Ho, Van Thi Thanh, Giang, Bach Long, Hong, Lu-Sheng, Nguyen, Nam Giang
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis 11.02.2017; Taylor & Francis Ltd
• Subjects: anti-reflection; Au coating; Black Si; thickness; wet chemical etch
• ISSN: 1542-1406; 1563-5287; 1527-1943
• DOI: 10.1080/15421406.2016.1277470

Black silicon (b-Si) has been a subject of great interest in various fields including photovoltaics for its ability to reduce significantly the surface reflectance so that b-Si can absorb more than 98% of light signing on them. We have fabricated the b-Si anti-reflection via metal-assisted etching process using gold (Au) layer assisted nano-porous etching in this study. The b-Si layers were produced through a simple and effective method consist of a thin Au coating (d < 10 nm) that played as a catalyst layer onto Si (100) wafers prior immersion in a HF-H 2 O 2 -H 2 O solution at room temperature, resulting catalyze formation of a network of [100]-oriented nanopores. The SEM observation suggested that the vertically columnar structure with a ∼300 nm deep nanopores layers can be formed in the limited synthesis conditions as well as achieved the extremely low reflectance about 2% at wavelength from 400-1000 nm.