Looking for solvents to etch FR4 and multilayer laminate

[meshmesh]

Solvents

Dear all,

does anyone know good selective solvents to etch the FR4 material and the multilayer laminate material without affecting copper .. ??

regards
meshmesh

 

[FoxyRick]

Re: Solvents

If you are trying to leave the copper patters so that you can inspect the design, it will be *very* difficult.

There are solvents for the resin that should leave the copper intact, but you will still be left with the glass matting. This will make seperation and inspection of the copper very difficult without messing up the placement of the tracks. Basically, you will end up with a pile of glass fibre strands and copper shapes all tangled together. There is no sensible solvent that will remove the glass. Hydrogen fluroide probably will, but I don't like it, it may attack the copper, and you will still be left with a jumbled tangle of copper tracks.

A much better way to reverse engineer a board is to depopulate it and check every pad for connectivity to every other. May take a long time, but not as much as the solvent method!

I have read several discussion over the years on this topic, always with this outcome.

Decapping IC's is much simpler!

Cheers,
FoxyRick.