How to remove IC coating from PCBs?

by uhe on Mon Nov 08, 2010 10:46 am

I'd like to know if there is any known (non hazardous) method to remove the black coating that gets placed over ICs on PCBs:
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Re: How to remove IC coating from PCBs?

by westfw on Mon Nov 08, 2010 11:18 am

Not really; that's a blob of epoxy, same as IC packages are made of. So you can look into the techniques used for dissolving IC packages. There was http://hackaday.com/2010/07/16/decappin ... -with-sap/

Note that what is underneath these "blobs" is typically not a "full" IC, but just a chip of silicon ("bare die") bound directly to the board ("Chip on board" technology.) The blob is not just "hiding" the chip, but is the only physical protection of the chip itself and some very fragile die wires.

http://www.tutorialsweb.com/smt/smd-com ... -board.htm
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Re: How to remove IC coating from PCBs?

by uhe on Mon Nov 08, 2010 12:12 pm

Thanks westfw,
I don't intend to play with nitric acid but I know a few chemists hmmmmmm
Dissolving because of the chip is not that interesting but a bare die... that would be a reason ;)
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Re: How to remove IC coating from PCBs?

by Agent24 on Thu Nov 03, 2011 12:24 am

Why would you want to dissolve the coating?
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Re: How to remove IC coating from PCBs?

by mkm558 on Tue Feb 05, 2013 6:13 pm

I want to remove the coating from PCB s, and IC s to expose the copper tracings for use in art. posting.php?mode=reply&f=44&t=17991#
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