Enhanced light trapping in thin film silicon solar cells deposited on PET and glass

The goal of this work is to reduce the production cost of thin-film silicon solar cells, by using PET substrates and thereby maintain a reasonable efficiency. The authors studied different kinds of textured back reflectors fabricated on glass and PET with the aim of increasing the short-circuit current density (J/sub sc/) in a-Si:H and /spl mu/c-Si:H n-i-p-type solar cells: random textures and periodic gratings were both tested. Compared to co-deposited cells on flat mirrors, the gain in J/sub sc/ is 15% for a-Si:H solar cells on randomly-textured PET at the initial state and 20% after light soaking, 8% for a-Si:H solar cells on gratings (so far only on glass and at the initial state) and 15.2% for /spl mu/c-Si:H solar cells on randomly-textured back reflectors, on glass. Best n-i-p a-Si:H solar cells on PET and /spl mu/c-Si:H cells on glass have so far reached 5.8% (after light-soaking) and 9.2% efficiencies, resp.