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. © 2002 American Institute of Physics.