Light management in flexible thin‐film solar cells on transparent plastic substrates. Issue 7 (8th March 2016)

• Record Type: Journal Article
• Authors: Wilken, Karen; Paetzold, Ulrich W.; Meier, Matthias; Ablayev, Gani M.; Terukov, Evgeny I.; Prager, Nicole; Fahland, Matthias; Finger, Friedhelm; Smirnov, Vladimir
• Is Part Of: Physica status solidi. Volume 213:Issue 7(2016:Jul.)
• Page Start: 1955
• Page End: 1963
• Publication Date: 2016-03-08
• Subjects: etching -- flexible solar cells -- light management -- nanoimprint lithography -- PET -- textures; Solid state physics -- Periodicals; Solids -- Industrial applications -- Periodicals; 530.41
• DOI: 10.1002/pssa.201532984
• Languages: English
• ISSNs: 1862-6300

Abstract

Abstract : Maintaining efficient light management is an essential part for obtaining high efficiency flexible thin‐film solar cells. Transparent plastic films like polyethylene terephthalate (PET) are a cost efficient substrate alternative but also impose additional constraints on the light management approaches available. In this study, we investigate and compare two approaches to prepare substrates with light scattering characteristics. We have developed low temperature ZnO:Al layers, which are fully compatible with PET substrates, and are textured by wet‐chemical methods. These low temperature textured ZnO:Al layers implemented in amorphous silicon solar cells on glass substrates result in similar efficiencies as highly optimized high temperature‐etched ZnO:Al layers. Nanoimprint lithography was used as an alternative light management approach and we show that an improved solar cell performance can be achieved on flexible PET substrates with both methods. Besides the effect on solar cell performance, pros and cons of both approaches with respect to flexibility in choice of materials and textures, fabrication process, stress evolution, and reproducibility are discussed.