link to homepage

Institute of Energy and Climate Research

Navigation and service

Flexible solar cells

Flexible solar cells benefit from low weight, flexibility and versatility regarding shapes and sizes of the module. These advantages make flexible solar cells attractive for a broad field of applications, such as building integrated photovoltaics, clothing and mobile applications, which is due to their low weight and versatility regarding shapes and sizes of the module. Additionally, the possibility to use roll-to-roll fabrication additionally facilitates high throughput production for extensive large area modules. To reduce the cost of the device, inexpensive plastic substrates like transparent polyethylene terephthalate (PET) can be used. The research of our group focuses on the development of thin-film silicon solar cells on these flexible transparent PET substrates. As the substrate is temperature sensitive, all fabrication steps of the solar cell need to be compatible with temperatures below 140 °C. This demands new concepts for e.g. the texturing of the film substrates, which is needed to maintain light trapping in the solar cell and therefore improved performance of flexible devices can be achieved. Our light management concepts involve development and application of advanced nanoimprint method, allowing to replicate required textures on flexible substrates. Other topics of interest include investigations of the effects of mechanical strain (e.g. bending) on the solar cell performance, upscaling of the process as well as the feasibility for industrial applications, investigated in collaboration with other research groups and industrial partners.

Front-Cover-RRLThin film silicon solar cell on low-cost and flexible PET substrate with nano-imprint light-trapping structure.
Copyright: Phys. Status Solidi R 9, 215-219 (2015)


K. Wilken, U. W. Paetzold, M. Meier, N. Prager, M. Fahland, F. Finger, and V. Smirnov, “Nanoimprint texturing of transparent flexible substrates for improved light management in thin-film solar cells,” Phys. status solidi - Rapid Res. Lett., vol. 4, pp. 215–219, Apr. 2015. []

K. Wilken, U.W. Paetzold, M. Meier, M. Smeets, N. Prager, M. Fahland, F. Finger and V. Smirnov, “Light Management in Flexible Thin-Film Solar Cells - The Role of Nanoimprinted Textures and Tilted Surfaces," IEEE Journal of Photovoltaics, DOI: 10.1109/JPHOTOV.2015.2470672 (accepted)


Dipl.-Ing. Karen Wilken

Dr. Vladimir Smirnov