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Looking for a UV curable plating resist which holds up in MSA Tin plating bath

2007

I am looking for a UV curable resist for a pattern plating application using Nickel Sulfamate, copper sulphate [on eBay or Amazon]and MSA Tin.

The resists we have tried so far have not been able to withstand the MSA in the Tin bath, does anyone have any ideas of resists or companies I should try?

Thanks Helen Dundas
Production Engineer NM

Helen Dundas
Production engineer - Albuquerque, NM

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2007

When I used positive photoresists (AZ 4620) for pattern generation on thin film sputtered ceramic substrates which where then electroplated with Au, Cu, or Ni, if I required additional chemical resistance of the photoresists, I would hard bake them at 100-120C for up to 1 hour after UV exposure and subsequent developing. This greatly increased the durability to acid etching as well, however, HNO3 would still attack the resists no matter what.
Another avenue might be to utilize a polyimide photoresist that could be patterned and hard baked at over 200-300C, basically making a "Kapton" photo pattern, which is extremely chemical resistant. The same materials are used as the flex circuit board materials for cellphones, and similar devices. Good luck!

Kevin Dowhower
- Lompoc, California, USA

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I have successfully used a product developed by LVH Coatings Ltd, Coleshill, West Midlands UK (www.clearclad.co.uk). They have developed a good UV curable electrophoretic photoresist that can withstand very low pH's. I believe the company has global outlets, including the USA. My major interest have been using it with sulphamate nickel and acid copper electroforming baths.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2007

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