Open AccessDisordered nanostructures by hole-mask colloidal lithography for advanced light trapping in silicon solar cells
Author(s) -
Christos Trompoukis,
Inès Massiot,
Valérie Depauw,
Ounsi El Daïf,
Ki-Dong Lee,
Alexandre Dmitriev,
Ivan Gordon,
R. Mertens,
Jef Poortmans
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.00a191
Subject(s) - materials science , wafer , silicon , lithography , optoelectronics , etching (microfabrication) , optics , nanotechnology , nanostructure , crystalline silicon , physics , layer (electronics)
We report on the fabrication of disordered nanostructures by combining colloidal lithography and silicon etching. We show good control of the short-range ordered colloidal pattern for a wide range of bead sizes from 170 to 850 nm. The inter-particle spacing follows a Gaussian distribution with the average distance between two neighboring beads (center to center) being approximately twice their diameter, thus enabling the nanopatterning with dimensions relevant to the light wavelength scale. The disordered nanostructures result in a lower integrated reflectance (8.1%) than state-of-the-art random pyramid texturing (11.7%) when fabricated on 700 µm thick wafers. When integrated in a 1.1 µm thin crystalline silicon slab, the absorption is enhanced from 24.0% up to 64.3%. The broadening of resonant modes present for the disordered nanopattern offers a more broadband light confinement compared to a periodic nanopattern. Owing to its simplicity, versatility and the degrees of freedom it offers, this potentially low-cost bottom-up nanopatterning process opens perspectives towards the integration of advanced light-trapping schemes in thin solar cells.