Plasma reactor for diamond layer deposition

摘要

The invention concerns a plasma reactor for generating and maintaining plasma. The plasma reactor comprises a resonant cavity (11) whose cross-section tapers in summit regions (13, 16) in which the wall (14) of the resonant cavity (11) is closed to such an extent that an excited field mode in the region of the cross-sectional tapered portions displays main peaks (15, 31) whose maximum field intensity is increased with respect to the field intensity of adjacent secondary peaks. A reaction unit (18) is provided in the region of a main peak (31) with a substrate (21) which is to be processed and which can be coated in the gas phase of the plasma (32). As a result of the field intensity distribution brought about by a resonant cavity (11) of the given shape, with main peaks (15, 31) which are greatly increased with respect to secondary peaks, process parameters such as gas pressure and coupled electromagnetic power can be selected very largely independently of one another when the plasma (32) is in a stable situation, without the plasma (32) igniting undesirably in the region of secondary peaks. Furthermore, the comparatively homogeneous field intensity distribution in the main peak (31) maintaining the plasma (32) causes the substrate (21) to be processed uniformly.