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Need a thin insulative coating for micro stainless steel housing

Q. My company builds a silicon chip device that is inserted into a very small metal tube housing. The OD is 0.015" and the ID is only 0.012". The problem I face is that the silicon circuit is leaking current into the housing. Since this is a implanted medical device, this is not acceptable.

I need to find a coating that will prevent this current flow. It should insulate both the inside and outside of the housing. The magnitude of the current is in the order of 2 milliamps.

Because my clearance from IC to housing is only 0.001" the coating must be very thin.

Peter Plouf
medical devices - London ,Ontario, Canada
2005

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A. A PVD coating might work. It depends on the aspect ratio of the hole. PVD coatings can go down holes, but not very far, maybe twice the diameter or so. Jim Treglio - scwineryreview.com PVD Consultant & Wine Lover - San Diego, California 2005 A. Your gap is really very small. If there is such a coating it will probably be a lacquer or enamel. Problem is to assure it remains impervious and dielectric after insertion due to possible damage. G. Marrufo-Mexico Guillermo Marrufo Monterrey, NL, Mexico 2005