Improvement of SiO₂ Properties by Heating Treatment in High Pressure H₂O Vapor

Abstract

Properties of SiO 2 and SiO 2 /Si interfaces formed by plasma chemical vapor deposition were improved by heating at 270°C in high pressure H 2 O vapor. The treatment reduced the fixed oxide charge density from 2.5×10 12 cm -2 (initial) to 8×10 10 cm -2 as the H 2 O 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 H 2 O 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 .