Plasma nanotexturing of silicon surfaces for photovoltaics applications: Influence of initial surface finish on the evolution of topographical and optical properties

Published

November 27, 2017

Author(s)

Guillaume Fischer, Etienne Drahi, Martin Foldyna, Thomas Germer, Erik V. Johnson

Abstract

Using a plasma to generate a surface texture with feature sizes on the order of nanometers ("nanotexturing") is a promising technique being considered for application in thin, high- efficiency crystalline silicon solar cells. This study investigates the evolution of the optical properties of silicon samples with various initial surface finishes (from mirror polish to various states of micron-scale roughness) during a plasma nanotexturing process. It is shown that during said process, the appearance and growth of nanocone-like structures are essentially independent of the initial surface finish, as quantified by the auto-correlation function of the surface morphology. During the first stage of the process (2 min to 15 min etching), the reflectance and light-trapping abilities of the nanotextured surfaces are strongly influenced by the initial surface roughness; however, the differences tend to diminish as the nanostructures become larger. For the longest etching times (15 min or more), the effective reflectance is less than 5% and a strong anisotropic scattering behavior is also observed for all samples, leading to very elevated levels of light-trapping.

Citation

Optics Express

Volume

25

Issue

24

Pub Type

Journals

Download Paper

https://doi.org/10.1364/OE.25.0A1057

Local Download

Keywords

black silicon, light-trapping, plasma nanotexturing, silicon photovoltaics

Citation

Fischer, G. , Drahi, E. , Foldyna, M. , Germer, T. and Johnson, E. (2017), Plasma nanotexturing of silicon surfaces for photovoltaics applications: Influence of initial surface finish on the evolution of topographical and optical properties, Optics Express, [online], https://doi.org/10.1364/OE.25.0A1057, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=923036 (Accessed April 19, 2024)