Process for forming a stack of different materials, and device comprising this stack

Abstract

A stack of layers defines a filter and is formed by copper on hydrogenated silicon nitride supported by a carrier. The filter includes a layer of hydrogenated silicon nitride, a layer of silicon oxide on the layer of hydrogenated silicon nitride and a layer of copper on the layer of silicon oxide. The layer of hydrogenated silicon nitride may have, in a vicinity of its upper side, a ratio of a number of silicon atoms per cubic centimeter to a number of nitrogen atoms per cubic centimeter lower than 0.8 (or even lower than 0.6), with a number of silicon-hydrogen bonds smaller than or equal to 6×1021 bonds per cubic centimeter (or even smaller than 0.5×1021 bonds per cubic centimeter). The filter further includes an additional layer of copper between the layer of hydrogenated silicon nitride and the carrier.

Dependencies are inferred from the claim text.