Plasma polymer films from sputtered polyimide

Deposition of plasma polymer films by r.f. magnetron sputtering of polyimide in an atmosphere of argon, nitrogen and in a self-sputtering mode is studied. In situ analytical techniques are applied to monitor the composition of both plasma and growing film during the deposition. A co-evaporation regime is observed at higher applied powers. Such a regime is characterized by a significant increase in deposition rate of plasma polymer films. In addition CO-based groups appear in the plasma volume and in the resulting films. The films deposited in a pulsed mode are similar in composition to those deposited in the continuous regime at equivalent power. The plasma polymer films are found to be stable to short-term oxidation in air.