Abstract
SiO2 films were prepared by plasma enhanced chemical vapor deposition (PECVD) using tetraethoxysilane (TEOS) and N2O. The Si-OH concentrations in the films deposited at a low temperature (200°C) was found to be below the detection limit of Fourier transform infrared spectroscopy (FTIR) with the RF Power more than 80W. Optical emission spectroscopic study for SiO2 deposition process in gas phase showed that emission intensities of both atomic oxygen and atomic hydrogen depended strongly on RF power. Further mass spectrometric study in N2O plasma indicated that atomic oxygen increased with RF power due to decomposition of N2O in N2 and O. In addition, we tried to prepare SiO2 films using TEOS and He in order to study the role of oxidant. It was found that low impurity SiO2 films can be obtained at temperarure lower than 200°C with higher RF power through the effects of oxidation by atomic oxygen and electron impact decomposition.
