Flexible amorphous and microcrystalline silicon tandem solar modules in the temporary superstrate concept

• Published in: Solar energy materials and solar cells 2007-04, Vol.91 (7), p.572-580
• Main Authors: van den Donker, M.N., Gordijn, A., Stiebig, H., Finger, F., Rech, B., Stannowski, B., Bartl, R., Hamers, E.A.G., Schlatmann, R., Jongerden, G.J.
• Format: Article
• Language: English
• Subjects: Applied sciences; Energy; Exact sciences and technology; Flexible; Natural energy; Photovoltaic conversion; Photovoltaic modules; Solar cells. Photoelectrochemical cells; Solar energy; Thin-film silicon
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2006.11.012

Encapsulated and series-connected amorphous silicon (a-Si:H) and microcrystalline silicon (μc-Si:H) based thin film silicon solar modules were developed in the superstrate configuration using an aluminum foil as temporary substrate during processing and a commodity polymer as permanent substrate in the finished module. For the development of μc-Si:H single junction modules, aspects regarding TCO conductivity, TCO reduction, deposition uniformity, substrate temperature stability and surface morphology were addressed. It was established that on sharp TCO morphologies where single junction μc-Si:H solar cells fail, tandem structures consisting of an a-Si:H top cell and a μc-Si:H bottom cell can still show a good performance. Initial aperture area efficiencies of 8.2%, 3.9% and 9.4% were obtained for fully encapsulated amorphous silicon (a-Si:H) single junction, microcrystalline silicon (μc-Si:H) single junction and a-Si:H/μc-Si:H tandem junction modules, respectively.