title: Nanoimprinted backside reflectors for a-Si:H thin-film solar cells: critical role of absorber front textures.
abstract: 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.
authors.forename: Yao-Chung
authors.initials: YC
authors.lastname: Tsao
authors.forename: Christian
authors.initials: C
authors.lastname: Fisker
authors.forename: Thomas Garm
authors.initials: TG
authors.lastname: Pedersen