A plasma sustained by electromagnetic surface waves (SW’s) has been used to study the deposition rateRof hydrocarbon and fluorocarbon plasma polymer films as a function of the applied field frequencyfin the range 12–400 MHz. The SW technique allows one to vary onlyfwhile keeping constant all other parameters known to influenceR, for example, power densityPin the plasma. A plot ofR/Pat a total pressure of 200 mTorr (27 Pa) displays two plateaus, that atf<30 MHz being about five times lower than that atf>100 MHz. This is attributed to the fact that electron energy distribution functions differ fundamentally at radio and microwave frequencies, for the gas pressure range considered.