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About nickel electroless plating

I want to plate a nickel film (onto Thicon, a glass which is sputtered with gold). I want to know what solution is required? (Do I need to buy several chemicals for activator, etc.) And what is the step of the electroless plating?
Thanks.

Leo Tam
University - Hong Kong
2005

Ed. note: Hello, Leo. We corrected a couple of spelling errors and changed some punctuation, but I'm not sure we got your question right. Could you please spend a couple of more paragraphs explaining in detail what you are trying to accomplish? Thanks.

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2005

Hello Leo,
It is funny that you want nickel over gold... normally people do the contrary.
First of all electroless nickel has only about 90% nickel and is amorphous (after deposition).

But the main problem is to plate over gold. Once I saw that it might be possible but you don't have a good adhesion (maybe because we cannot prepare gold).
If you can achieve an oxidoreaction between gold and plating, then you can put electroless nickel over plating.
But I don't know if it's possible and it is surely "very expensive"
Then you can try any eless nickel bath (Schloetter, Durnicoat, ...) you can get from 5% to 15% Phosphor in your nickel.
Regards,

Gregory Bellynck

Bellynck Gregory
semiconductor - Regensburg, Germany

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Thanks for reply my question. The adhesion is not the problem as I will etch away the gold after plating. However, after reading some books, I saw that mixed colloidal catalyst is required before the electroless plating. I want to know that if I already have gold surface on the surface, can I omit this part and directly immerse the glass with sputtered gold after cleaning? (As I want to use photoresist as a barrier for patterning, immersion of that catalyst may cause the plating on both gold and photoresist surface.)
Thanks.

Leo Tam
University - Hong Kong
2005

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Yes you can skip that step when the object you wish to electroless plate (autocatalytic plate) is already conductive. I am not sure, however, whether gold is catalytic to nickel (I doubt that it is). That means you need to 'spark' the plating to get it started, i.e., apply electricity for a second to get the first few atoms of nickel deposited onto the gold.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005

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2005

I think everything can be plated without "catalyst"... that is the reason for plating problem and instability...

Sometimes I get nickel on non conductive materials (but organic resist work fine to protect from plating). I think it won't be difficult to plate on gold. If you have your own chemicals, try to reduce the stabilizer concentration or simply remove it.
Regards,

Gregory

Bellynck Gregory
- Regensburg, Germany