🚀 go-pugleaf

In article <C0nqAB.55B@gantz.bowlgreen.oh.us> gantzm@gantz.bowlgreen.oh.us (Michael L. Gantz) writes:
>I have been reading all the articles concerning the etching of circuit
>boards, something I have a great need to do.  And they all assume that
>one would be etching the copper off of the board.  Is it possible for
>the home hobbyist to devise a system to deposit copper onto blank
>boards?
>
>I would picture a system where the hobbyist would pre-drill a blank
>board, then treat it with a photo-sensitive material.  After the
>photo-sensitive material has been applied both sides of the board
>would be exposed.  The exposed images would then be developed most
>likely in a chemical process.
>
>After the circuit images have been developed the board would then be
>treated either chemically or electrically to bond copper to the traces
>developed on the board.  The might solve the problem of plated through
>holes as they might get coated also.
>


Here would be a possible process, and the problems I see -

A) predrill blank panel ( no copper)
B) resist, expose, develop, bake, touchup - negative image
C) electroless plate entire surface
   
   electroless plating requires a surface that allows some of the
catalylst (typically rubidium chlorides) to soak in - this is easy
in holes, smooth surfaces are hard to do this on... but say you got this
to work somehow.

D) remove resist

  Electroless copper is very delicate, and you'd have to be able to
not damage it on removal... this is another real good place for problems.

E) Ok, now elecltroplate the entire board.

   this would be difficult also since you need to be able to tie all the
copper segments together to plate them - kinda tough. Ok, so, for some
boards lAyouts it would work.  I dunno if the electrical characteristics of
plated copper would be OK. And, Economically, - 1) Copper cost from
electroplating lots of copper on a board is high and, 2) Possible high
energy cost of electroplating lots of copper



Ok, so, you say, take out step E & D and just do electroless deposition.
You could, I suppose, but .... I've found *that* to be a very tricky
*and* time consuming thing in itself for a very thin layer. it's very
unlikley you will be able to get away with ONLY electroless. Also the grain
tends to be large which would not conduct uniformly.





-- 
Alex P. Novickis, Real Time systems demi-guru.  (W)   408-862-4541
ALINK:alex.n                                    (H)   415-691-0657
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