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Electroless Pb deposition

1998

Hello,

I am interested in any technique and/or chemistry that would allow us to deposit a thin lead(Pb) coating in a 60 to 1 high aspect ratio structure.

Specifically we are attempting to deposit this lead coating on the sidewalls of a six micron diameter opening three hundred microns deep. This channel is opened at both ends. We have successfully deposited nickel onto the sidewalls but are experiencing some difficulties in the lead coating. We have attempted traditional electroplating methods inclusive of pulse plating at high frequencies. Are there any electroless formulations for lead(Pb) chemistries?

Any help in direction or methods would be appreciated.

Many thanks,

Sincerely,
bob boerstler

Robert Boerstler
- Oxford, Connecticut

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Since it is a through-hole, the practicle aspect ratio is about 25 to 30 I assume. I can think of 3 scenarios without consideration to practicality: 1) make a bigger hole, and fill it with molten lead using vacuum suction, then drill a smaller hole; 2) go to Jet Process Corporation in New Jersey, they use a vapor jet that migh be suitable; 3) new vapor-dep process development, I have one in mind for a while. We could talk when you are ready.

Mandar.

Mandar Sunthankar
- Fort Collins, Colorado
1998

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Dear Mr Boestler

Although I have nothing at this time to contribute to the solution of your problem I have an interest in the subject about which you are inquiring, from a different aspect than yours. I am attempting to coat aluminum foam with lead. I accomp lished this by dipping the articles in molten lead over a previously deposited Zincate coating. The results are far from satisfactory. Perhaps you would be able to guide me to sources of information which have resulted from your inquiry that would enlighten me Thank you Sincerely Yours

Frank C. Farrell
- Las Vegas Nevada
1999

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