New progress in the fabrication of n-i-p micromorph solar cells for opaque substrates

作者：Biron Remi^*; Haenni Simon; Boccard Mathieu; Pahud Celine; Soederstroem Karin; Duchamp Martial; Dunin Borkowski Rafal; Bugnon Gregory; Ding Laura; Nicolay Sylvain; Parascandolo Gaetano; Meillaud Fanny; Despeisse Matthieu; Haug Franz Josef; Ballif Christophe

来源：Solar Energy Materials and Solar Cells, 2013, 114: 147-155.

DOI：10.1016/j.solmat.2013.02.032

• Thin film silicon solar cells
• Micromorph
• Light trapping
• Back reflector
• Intermediate reflector

In this paper, we investigate tandem amorphous/microcrystalline silicon solar cells with asymmetric intermediate reflectors grown in the n-i-p substrate configuration. We compare different types of substrates with respect to their light-trapping properties as well as their influence on the growth of single-junction microcrystalline cells. Our most promising back reflector combines a textured zinc oxide film grown by low-pressure chemical vapor deposition, a silver film for reflection, and a zinc oxide buffer layer. Grown on this substrate, microcrystalline cells exhibit excellent response in the infrared while keeping high open-circuit voltage and fill factor, leading to efficiencies of up to 10.0%. After optimizing the morphology of the asymmetric intermediate reflector, we achieve an n-i-p micromorph solar cell stabilized efficiency of 11.6%, using 270 nm and 1.7 mu m of silicon for the absorber layer of the amorphous top cell and the microcrystalline bottom cell, respectively. Using this original device architecture, we reach efficiencies close to those of state-of-the-art n-i-p and p-i-n micromorph devices, demonstrating a promising route to deposit high-efficiency thin-film silicon solar cells on opaque substrates.

• 出版日期2013-7