Plasma polymerization of ethylene by magnetron discharge

The deposition rate of plasma-polymerized ethylene is measured on the electrode and on a substrate placed midway between electrodes in a capacitively coupled system with internal electrodes. Polymerization is carried out under a variety of conditions including low flow rate and pressure, high flow rate and pressure, three frequencies (60 Hz, 10 kHz, 13.56MHz), and with and without a magnetic field at the electrodes. It is found that the low pressure (30–50 mTorr) plasma yields considerably higher conversion of monomer to polymer at the substrate than the high-pressure plasma (500 mtorr). With a low-pressure plasma, the use of magnetic field results in higher deposition rates at a given power input. A plasma polymer which adheres exceptionally well to aluminum is formed only midway between electrodes (not at the electrodes) in the 10-kHz and 13.56-Mhz low-pressure plasma.