Modeling of the electrical properties of polycrystalline ceramic semiconductors with submicron grains

A numerical model for simulation of the microstructure and electrical properties of semiconductor ceramic materials is presented. For the case of the average grain size being comparable to the grain boundary depleted region and the double Schottky barriers of the neighboring grain boundaries overlap. The two-dimensional (2D) simulation is performed in the drift-diffusion approximation using Voronoi network method. The influence of the grain size on the volt-ampere characteristic and specific electrical capacitance is analyzed for p-type SrTiO3.