Influence of the Structure of a-SiOxNy Thin Films on Their Electrical Properties

Amorphous silicon oxynitride thin films with composition varying from silicon nitride to silicon oxide were deposited by rf sputtering of a silicon target under different argon–oxygen–nitrogen atmospheres. The FTIR and XPS investigations revealed the presence of a mixture of SiO2, Si3N4 and a‐SiOxNy phases. The structural defects were identified and quantified by means of ESR analysis which showed the presence of silicon dangling bonds on decreasing the density which subsequently increases the oxygen content. C–V and I–V measurements were carried out on Pt‐SiOxNy‐Pt type structures. Permittivity and conductivity values were found to be dependent on both film composition and structure. The conductivity values were found to be low.