Antireflective silicon nanostructures with hydrophobicity by metal-assisted chemical etching for solar cell applications
1 School of Information and Mechatronics, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712, South Korea
2 Department of Nanobio Electronics and Materials, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712, South Korea
Nanoscale Research Letters 2013, 8:159 doi:10.1186/1556-276X-8-159Published: 8 April 2013
We present broadband antireflective silicon (Si) nanostructures with hydrophobicity using a spin-coated Ag ink and by subsequent metal-assisted chemical etching (MaCE). Improved understanding of MaCE, by conducting parametric studies on optical properties, reveals a design guideline to achieve considerably low solar-weighted reflectance (SWR) in the desired wavelength ranges. The resulting Si nanostructures show extremely low SWR (1.96%) and angle-dependent SWR (<4.0% in the range of 0° to 60°) compared to that of bulk Si (SWR, 35.91%; angle-dependent SWR, 37.11%) in the wavelength range of 300 to 1,100 nm. Relatively large contact angle (approximately 102°) provides a self-cleaning capability on the solar cell surface.