Shrinking device geometry has produced a need for lower dielectric constant materials for intermetal dielectric to reduce circuit RC time constants and intertrace "cross-talk" capacitance and reduce power consumption at high frequency. One such material is F-doped SiO2. This study utilized an electron cyclotron resonance high-density oxygen plasma source to produce SiO2 from a mixture of SiH4 and SiF4, O-2, and Ar. The total silicon gas flow was held constant and the ratio of SiH4 to SiF4 was varied from 0% to 100%. The fluorine content was measured using nuclear resonance analysis (NRA) with the reaction F-19(p,alpha gamma)O-16. A comparison of the NRA data and the ratio of the Fourier transform infrared Si-F absorbance near 934 cm(-1) to the Si-O peak near 1080 cm(-1) gives a proportionality constant of 144. The refractive index and dielectric constant were determined as a function of fluorine content. The dielectric constant decreased linearly from 4.0 at zero F to 3.55 at 10.5 at. % F and the refractive index decreased from 1.474 to 1.417, Film stress, thermal stability, moisture absorption, and electrical breakdown were also measured. Film stress decreased from 150 to 70 MPa compressive as the F content increased.