An analytical model for rectifying contacts on polycrystalline semiconductors

A simple approach allows the calculation of the electrostatic potential of rectifying junctions on polycrystalline semiconductor. We exemplify the method for Schottky contacts and compute the junction capacitance and the electrical field at the metal-semiconductor interface. For fine grained material, significant tunnelling may occur if the density of states at the grain boundaries is high. These states are also responsible for a quasi-static junction capacitance which is independent of voltage.