Mass densification and defect restoration in chemical vapor deposition silicon dioxide film using Ar plasma excited by microwave

Abstract

Silicon dioxide (SiO2) films formed by chemical vapor deposition (CVD) have been treated with Ar plasma excited by microwave. The changes of the mass densities, carrier trap densities, and thicknesses of the CVD-SiO2 films with the Ar plasma treatments were investigated. The mass density depth profiles were estimated with X-Ray Reflectivity (XRR) analysis using synchrotron radiation. The densities of carrier trap centers due to defects of Si-O bond network were estimated with X-ray Photoelectron Spectroscopy (XPS) time-dependent measurement. The changes of the thicknesses due to the oxidation of Si substrates were estimated with the XRR and XPS. The mass densities of the CVD-SiO2 films are increased by the Ar plasma treatments. The carrier trap densities of the films are decreased by the treatments. The thicknesses of the films are not changed by the treatments. It has been clarified that the mass densification and defect restoration in the CVD-SiO2 films are caused by the Ar plasma treatments without the oxidation of the Si substrates.