Hi Ed,

I have plenty first-hand experience with all three types of foil. My opinion is that they all do equally well on fine line (5 mil line/spacing and under) works.

Double treat material is primarily used by small, quick turn shops for eliminating the preclean and oxide processes. DSTF really has no advantage over untreated copper if you don't give up preclean and still micro-etch in the subsequent oxide process. For fine line works, imaging is the most important process. Materials, treated or not, have little to do with what graphics definition you put on them. Once you weed out the exposure problems and operator errors you will have reasonable yields.

Yu-Shan Han, Ph.D., P.E.

Lead One Technology, Inc.

Seattle, WA

(206) 368-8429

-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Ed Cosper
Sent: Monday, August 09, 1999 1:55 PM
To: [log in to unmask]
Subject: [TN] Copper foil and fine line circuits

Hi all,

I am looking for feedback on the preferred foil treatment for use on .005" lines/spaces innerlayers. Doubletreat, Reverse treat, no treat with oxide, some other foil??????? All recommendations and reasons why would be appreciated?

Thanks for your help.

Ed Cosper