Electrical properties in silicon oxynitride and silicon nitride prepared by plasma-enhanced chemical vapor deposition

We have investigated the conduction mechanism of a-SiO_xN_y:H and a-SiN_z:H films by measuring the conduction current and the capacitance-voltage characteristics in MIS structure capacitors. The low-field conduction is attributable to an Ohmic process and the high-field conduction is attributable to Poole-Frenkel emission for both materials. From the similarity of many aspects of the conduction process, it is considered that the carriers are transported via the same sites associated with Si-N bonds located in the forbidden band in both materials