Stationary aperture plate for reactive sputter deposition

Abstract

The aperture plate of the present invention is positioned between a sputter target and a substrate to be coated with a film of target material. The substantially non-collimating plate contains a plurality of apertures which intercept a percentage of the sputter particles while allowing other sputter particles to be deposited upon the substrate to form the film. The rate of deposition achieved by the aperture plate is less than the rate of sputtering so that the target may be sputtered at a sufficiently higher rate to reduce the formation of a reactant film on the sputter target while the deposition rate is sufficiently low to allow adequate reaction between a reactive gas and sputter particles to form the desired reactant film on the substrate. In accordance with another aspect of the invention, the apertures of the plate have different aspect ratios or different densities in various different regions of the plate to achieve various different deposition rates in different areas of the substrate. The aspect ratios of the apertures may be selectively varied to achieve a more uniform film thickness or a film of selectively varied thicknesses. The various aspect ratios are achieved by selectively varying a cross-sectional area and/or depth of the apertures in the plate.