The authoritative public forum
  for Metal Finishing 1989-2025
  

  -----

Metallic resist for cupric chloride etchant?

 

We are a flexible printed circuit manufacturer and use a Cupric Chloride (acid based) etchant. While this is fine for a photoresist process, I would like to know if anyone has experience using any metallic platings as an etch resist ? Someone suggested a tin-nickel plate, does that work? It is my experience that this etchant will etch nickel, tin, tin lead.. etc. Any experience or suggestions?

Richard Breslin
- Lowell, Massachusetts

--
Ed. note: You may want to hear "The Lost Art of Tin-Nickel Plating".

---

I would think that something along the lines of gold would work.

James Totter, CEF
- Tallahassee, Florida
 

I know those who have used gold successfully as a resist in cupric etching processes. You must control carefully because you can undercut the nickel and cause gold slivers.

Scott Campbell
- Tempe, Arizona, USA

You will find that gold works well, We usually use about 1 micron of hard gold with no nickel.

John Yarno
- Snoqualmie, Washington