Photo-carrier transport in nanocrystalline silicon films

Randomly distributed grain and grain boundaries dominate the electronic transport in hydrogenated nanocrystalline silicon films (nc-Si:H) at relatively high temperatures. At temperatures below 100 K, the effect of grain boundaries on photoconductivity is ignored and hence a standard transport model for homogeneous semiconductors can be applied to explain the experimental results. A reasonable value of μτ-product is predicted and is very close to that obtained experimentally. One of the important factors, an extent of barrier height distribution, can be also deduced from the present formulation.