Improvement of SiO 2 Properties by Heating Treatment in High Pressure H 2O Vapor

Properties of SiO2 and SiO2/Si interfaces formed by plasma chemical vapor deposition were improved by heating at 270°C in high pressure H2O vapor. The treatment reduced the fixed oxide charge density from 2.5×1012 cm-2 (initial) to 8×1010 cm-2 as the H2O vapor pressure increased to 54 bar. The peak frequency of the absorption band caused by the Si-O antisymmetric stretching vibration mode was increased to 1078 cm-1 for treatment with 54 bar H2O vapor, while it was 1062 cm-1 before the treatment. The full width at half-maximum of the absorption band was reduced to 65 cm-1.