UN METODO DE CONTROLAR EL TAMANO DEL AREA DE SUPERFICIE DE UN ELECTRODO DESDE EL CUAL SE GENERA UN PLASMA EN UN PROCESO DE REVESTIMIENTO POR DEPOSICION DE VAPOR.

摘要

Vapour deposition coating can be performed in equipment in which a plasma of the coating material is generated from the surface of an electrode. The surface area of the electrode from which the plasma is generated can be selectively adjusted by exposing the plasma generating surface of the electrode to the effect of a magnetic field and adjusting the strength of the magnetic field to spread the plasma over the evaporation surface of the electrode in order to permit more efficient use of the electrode. Preferably the electrode is in the form of a flat disc of metal (e.g. titanium) and the magnetic field is generated by a permanent magnet or an electromagnetic coil which substantially surrounds or is coaxial with the electrode, the electrode or an associated element acting as the core of the coil. (Figure 1).