Open AccessNanoimprinted backside reflectors for a-Si:H thin-film solar cells: Critical role of absorber front textures
Author(s) -
Yao-Chung Tsao,
Christian Fisker,
Thomas Garm Pedersen
Publication year - 2014
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.22.00a651
Subject(s) - materials science , nanoimprint lithography , fabrication , silicon , optics , thin film , optoelectronics , solar cell , amorphous silicon , plasmonic solar cell , polymer solar cell , crystalline silicon , nanotechnology , medicine , alternative medicine , physics , pathology
The development of optimal backside reflectors (BSRs) is crucial for future low cost and high efficiency silicon (Si) thin-film solar cells. In this work, nanostructured polymer substrates with aluminum coatings intended as BSRs were produced by positive and negative nanoimprint lithography (NIL) techniques, and hydrogenated amorphous silicon (a-Si:H) was deposited hereon as absorbing layers. The relationship between optical properties and geometry of front textures was studied by combining experimental reflectance spectra and theoretical simulations. It was found that a significant height variation on front textures plays a critical role for light-trapping enhancement in solar cell applications. As a part of sample preparation, a transfer NIL process was developed to overcome the problem of low heat deflection temperature of polymer substrates during solar cell fabrication.