IMPROVEMENT OF SIO2/SI INTERFACE BY LOW-TEMPERATURE ANNEALING IN WET ATMOSPHERE

A postannealing technique was developed in order to improve the quality of SiO2 films formed by a parallel-plate remote plasma chemical vapor deposition. The wave number of the antisymmetric stretching mode of Si-O-Si bonding in the SiO2 film increased from 1058 to 1069 cm-1 by an annealing in H2O vapor at 270°C. It was estimated that averaged bonding angle of Si-O-Si was widened from 137.8°to 141.0°. The annealing in the H2O vapor ambient at 270°C for 30 min efficiently reduced the interface trap density to 2.0×1010cm-2 eV-1 and the effective oxide charges density from 7×1011 to 5×109 cm-2 for a metal-oxide-semiconductor (MOS) diode using the SiO2 film.© 1995 American Institute of Physics.