Hydrogenated microcrystalline silicon (µc-Si:H) thin films were prepared by hot-wire chemical vapor deposition. Large grains containing nano-sized crystallites were observed by scanning electron microscopy. The change in defect density in the absorbers of experimentally-prepared solar cells as a function of crystalline volume fraction was estimated from a comparison of simulated results using an AMPS-1D device simulator and previously reported solar cell performance. The modelled structure of grains in µc-Si:H thin films which was built, based on the observed results, was combined with the estimated defect density in the i-layer. The combination showed that the change in defect density in the i-layer of a solar cell could be explained well by employing the assumption that the defects existed at boundaries between the large grains; not between the nano-sized crystallites.

Characterization of Defects-Location in Hydrogenated Microcrystalline Silicon Thin Films and Its Influence on Solar Cell Performance. S.Hiza, A.Yamada, M.Konagai: Japanese Journal of Applied Physics, 2008, 47, 6222-7