Nanoimprint texturing of transparent flexible substrates for improved light management in thin‐film solar cells. Issue 4 (12th March 2015)

• Record Type: Journal Article
• Authors: Wilken, Karen; Paetzold, Ulrich W.; Meier, Matthias; Prager, Nicole; Fahland, Matthias; Finger, Friedhelm; Smirnov, Vladimir
• Is Part Of: Physica status solidi. Volume 9:Issue 4(2015:Apr.)
• Page Start: 215
• Page End: 219
• Publication Date: 2015-03-12
• Subjects: flexible substrates -- solar cells -- texturing -- light trapping -- thin films; Solid state physics -- Periodicals; 530.4105
• DOI: 10.1002/pssr.201510040
• Languages: English
• ISSNs: 1862-6254

Abstract

Abstract : We present a nanoimprint based approach to achieve efficient light management for solar cells on low temperature transparent polymer films. These films are particularly low‐priced, though sensitive to temperature, and therefore limiting the range of deposition temperatures of subsequent solar cell layers. By using nanoimprint technology, we successfully replicated optimized light trapping textures of etched high temperature ZnO:Al on a low temperature PET film without deterioration of optical properties of the substrate. The imprint‐textured PET substrates show excellent light scattering properties and lead to significantly improved incoupling and trapping of light in the solar cell, resulting in a current density of 12.9 mA/cm 2, similar to that on a glass substrate. An overall efficiency of 6.9% was achieved for a flexible thin‐film silicon solar cell on low cost PET substrate. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) Abstract : Transparent polymer substrates enable the fabrication of flexible solar cells at low cost, yet narrow the choice of applied processes by additional requirements such as lower temperature limits. This Letter presents a nanoimprint lithography approach to achieve efficient light management schemes at low temperatures without deterioration of the optical properties of the substrate, significantly improving the performance of flexible solar cells.