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Reduction of an oxidized copper layer (100nm thickness)

Hi

I would like to do nickel plating on a silicium substrate. Therefore I use a silicium wafer with a titanium layer (100 nm) sputtered on it. On that layer a copper layer is added (also sputtered I think, and also 100 nm). Now this copper layer has been oxidized, and I would have to reduce it again, so it would be possible to do the copper deposition. Anyone has an idea

Arne de Meester
student -- stage - Turnhout, Antwerp, Belgium
2004

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There is no way you will be able to chemically clean the copper - it is just too thin and you will lose it. If the oxide is not too extensive, you may be able to recover some of it by ion bombardment in a reducing atmosphere and/or vacuum. I know that sounds contradictory, but if you create a working vacuum in a chamber previously filled with a reducing gas, there will be enough reducer to perhaps do the job. Alternatively, contact a vacuum coating company in Belgium - you have some really good ones out there who are at the forefront of the technology.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2004