ON THE ENERGY-BALANCE OF SUBSTRATE SURFACES DURING PLASMA CLEANING OFLUBRICANTS

During de oxygen plasma cleaning of hydocarbon-containing light lubric ants deposited on aluminum the energy fluxes towards the substrates ha ve been determined by temperature measurements. The contributions to t he total energy influx are due to exothermic combustion reactions of t he petroleum-like lubricants by the plasma generated oxygen atoms and due to kinetic ion energy transfer. By variation of the discharge mode and substrate voltage the effect of the two contributions could be se parated. In the anomalous glow discharge mode, where the ion energy in flux was of importance, the treated substrates were at cathode potenti al (-500 to -1200 V) and vice versa, in the hollow cathode discharge m ode the substrates were at floating potential where only the chemical component contributes to substrate heating. A comparison of the measur ements with calculations based on simple model assumptions is given. ( C) 1997 Elsevier Science Ltd. All rights reserved.