Characterization and modeling of electrical transport in undoped hydrogenated microcrystalline silicon

Abstract

In this paper, we present the characterization and modeling of the electrical transport of hydrogenated microcrystalline silicon (μc-Si:H). Electrical conductivity measurements for several crystalline fractions have been carried out. The latter have been combined with surface potential measurements from atomic force microscopy in order to investigate the electrical transport in the heterogeneous structure. We propose a new numerical model based on a three-dimensional electrical circuit to extract the parameters involved in the transport. A physical based model of tunneling at large grain boundary is implemented. Combining the latter with other conductivities in the large electrical circuit, the percolation behavior in respect to crystalline fraction is fully simulated. A benefit of such a model is that it captures the fundamental physics phenomena with only a few comprehensible parameters.