Compositional and structural studies of amorphous silicon-nitrogen alloys deposited at room temperature using a sputtering-type electron cyclotron resonance microwave plasma

Abstract

Abstract High-quality amorphous silicon-nitrogen alloys (a-SiN x ) have been deposited at room temperature by a sputtering-type electron cyclotron resonance (ECR) plasma. A detailed analysis of the properties of a-SiNx films in terms of their composition, microstructure and dielectric characteristics was performed using X-ray photoelectron spectroscopy, infrared (IR) spectroscopy and ramp current-voltage measurement techniques. Their characteristics were correlated with the N2 gas flow rate (NGFR) in the ECR plasma formation. The dependence of solid-state [N]/[Si] ratios in the films on the NGFR indicated that the film composition changed from non-stoichiometry to stoichiometry as the NGFR increased from 0.5 to 1 seem. The dependence of the IR spectra on the NGFR indicated that silicon nitride network was well ordered for an NGFR of 1 seem, in which the dielectric breakdown-field was over 4 MVcm−1. However, when the NGFR was over 1 seem, significant N≡N triple bonds (gaseous N2 molecule) were formed ...