The variation of residual stress with the water absorption was reduced drastically by the N2O plasma treatment for fluorinated silicon-oxide thin films. Fourier transformed infrared spectroscopy analysis showed that the film was oxidized by the plasma treatment. It was also determined that the oxidation occurred on the film surface from the P-etch rate and x-ray photoelectron spectroscopy analysis. The experimental results show that the stabilization results from the oxidation of the surface by the N2O plasma treatment.

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Fluorinated silicon-oxide (SiOF) films were produced by electron-cyclotron-resonance plasma-enhanced chemical-vapor deposition. The effect of water absorption on the film properties was studied by measuring the residual stress as a function of exposure time to room air. The residual stress shows an increase of the compressive component as the film absorbs water. However, the chemical bonding structure does not change after the water absorption. The residual stress returns to the initial value when the film is dried. It is suggested that the water absorption occurs entirely by physical adsorption of H2O molecules to Si–F bonds.

Fluorinated silicon oxide (SiOF) films were deposited by electron cyclotron resonance plasma enhanced chemical vapor deposition (ECRPECVD). The behavior of residual stress w as studied with water absorption. SiOF film showed compressive stress after deposition. The compressive stress increased after the exposure to room air. Fourier transformed infrared (FTI R) spectroscopy analysis was carried after the water absorption. However, the change of chemical bonding structure was not observed during the water absorption in this study. After the exposu re to room air, the films were kept in dry air. The residual stress returns to the initial value after 1 week. Considering the results of the residual stress and FTIR analysis, it is supposed that the water absorption in this study occurs entirely by physical adsorption of H2O molecules to Si-F bonds on the surface.