Metal film protection of the surface of a structure formed on a semiconductor substrate during etching of the substrate by a KOH etchant

摘要

The present invention concerns the field of microstructures and in particular microstructures made via CMOS technology on semiconductor substrates intended to undergo micro-machining by wet chemical etching, in particular by a KOH etchant.According to the present invention, protection against the KOH reactive agent is provided to such a structure by the deposition of a metal film (40, 41, 43) including at least on external gold layer (43) on the surface of the structure.This metal film (40, 41, 43) advantageously allows the use of mechanical protective equipment to be omitted and thus allows the wafers to be processed in batches. The present invention also proves perfectly compatible with a standard gold bumping process.