For those PWB shops doing panel plate, photoresist acts as the etch resist.
It can be either dry film or electrophoretic (electro-deposited).
Though not done much in the U.S., a positive-acting ED photoresist
completely protects the hole/via walls and also permits extremely small or
no pads around vias.  It is much thinner and adheres better than a dry film
resist, which can benefit the etching process.  In addition, the process can
be incorporated into the automatic copper plating line (panel plate only).

Patty
Patricia J. Goldman
PPG Industries, Inc.
412-492-5516
[log in to unmask]


-----Original Message-----
From: Howieson, Rick [mailto:[log in to unmask]]
Sent: Friday, February 11, 2000 10:14 AM
To: [log in to unmask]
Subject: [TN] Etch Resist


Hello All,
Aside from Tin or Tin Lead, on outers, what else is being used for an
etch resist? Anything new or in development?
Have a good FRIDAY!
Rick Howieson
GTC
http://www.gt-corp.com

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