LATEST RESULTS ON STABILIZED FLEXIBLE THIN FILM SILICON SOLAR CELLS

ABSTRACT: Our primary goal is to increase the stabilized efficiency of thin film silicon solar cells in the substrate (nip) configuration by using textured substrates and tandem structures, based on amorphous (a-Si:H) and microcrystalline silicon (μc-Si:H). In order to reduce costs of mass-produced thin film solar modules, special attention has been paid in developing processes compatible with plastic foils and roll to roll technology. In this report, we give an overview on the current status of development of solar cells in the nip configuration at IMT Neuchâtel. In summary, the best stabilized efficiencies were: 7.0% for an amorphous solar cell (with an absorber layer thickness of 270 nm), 8.7 % for a microcrystalline solar cell (with an absorber layer thickness of 1.2 µm), 8.0 % for an amorphous tandem solar cell, and 9.0 % for a micromorph tandem solar cell. In addition, damp heat tests on encapsulated flexible a-Si:H solar cells with a textured back reflector showed no degradation of the electrical parameters