Argon Content of SiO2 Films Deposited by RF Sputtering in Argon

When SiO
2
is deposited by sputtering in an argon rf glow discharge, the films so produced contain considerable amounts of trapped argon, as determined by x-ray fluorescence analysis. This argon content was measured as a function of various sputtering parameters: argon pressure, rf power, electrode spacing, substrate temperature, and magnetic field, the latter two being most influential. A simple theoretical model for the capture and release of argon is presented which explains an observed linear decrease of the argon concentration in SiO
2
with increasing temperature. Incorporation of argon into the sputtered SiO
2
film does not seem to impair the film's ability to act as a good passivating and insulating layer.