Nano Archive

ZnO nanostructures as efficient antireflection layers in solar cells

Lee, Yun-Ju and Ruby, Douglas S. and Peters, David W. and McKenzie, Bonnie B. and Hsu, Julia W. P. (2008) ZnO nanostructures as efficient antireflection layers in solar cells. NANO LETTERS, 8 (5). pp. 1501-1505.

Full text is not hosted in this archive but may be available via the Official URL, or by requesting a copy from the corresponding author.

Official URL: http://dx.doi.org/10.1021/nl080659j

Abstract

An efficient antireflection coating (ARC) can enhance solar cell performance through increased light coupling. Here, we investigate solution-grown ZnO nanostructures as ARCs for Si solar cells and compare them to conventional single layer ARCs. We find that nanoscale morphology, controlled through synthetic chemistry, has a great effect on the macroscopic ARC performance. Compared with a silicon nitride (SiN) single layer ARC, ZnO nanorod arrays display a broadband reflection suppression from 400 to 1200 nm. For a tapered nanorod array with average tip diameter of 10 nm, we achieve a weighted global reflectance of 6.6%, which is superior to an optimized SiN single layer ARC. Calculations using rigorous coupled wave analysis suggest that the tapered nanorod arrays behave like modified single layer ARCs, where the tapering leads to impedance matching between Si and air through a gradual reduction of the effective refractive index away from the surface, resulting in low reflection particularly at longer wavelengths and eliminating interference fringes through roughening of the air-ZnO interface. According to the calculations, we may further improve ARC performance by tailoring the thickness of the bottom fused ZnO layer and through better control of tip tapering.

Item Type:Article
Subjects:Physical Science > Nano objects
Technology > Nanotechnology and energy applications
Material Science > Nanochemistry
ID Code:2385
Deposited By:Anuj Seth
Deposited On:17 Dec 2008 13:01
Last Modified:20 Jan 2009 10:31

Repository Staff Only: item control page