James, Eddie, Cupric chloride yields the highest etch factor of all etchants. Using cupric, the etch factor ranges from 2:1 on up to 6.7:1, depending on the type of controller used. The answer to obtaining and easily maintaining a higher etch factor is to reduce your free acid down to zero and to raise your copper content above 30 oz/gal. Please contact me off line for complete details at: [log in to unmask] Phil ------------------------------ > Date: Tue, 7 Jul 1998 07:18:57 -0700 > From: James Patten <[log in to unmask]> > Subject: etch factor > > REGARDING [TN] etch factor > > What is typical etch factor for 1oz Cu these days? What about 2oz? What = > is a > common trace-space that suppliers see these days? Thanks. > > ------------------------------ > > Date: Tue, 7 Jul 1998 15:42:10 +0100 > From: Eddie Brunker <[log in to unmask]> > Subject: Re: etch factor > > At 07:18 07/07/98 -0700, you wrote: > > REGARDING [TN] etch factor > > > >What is typical etch factor for 1oz Cu these days? What about 2oz? What is a > >common trace-space that suppliers see these days? Thanks. > > > > May I extend that question from the assembly point of view... > and ask what overall reduction is seen on pads and traces on 1/2 oz outer layer? > Due not only to etching but also because of collimation?? tolerance. > > Thanks > > ------------------------------ > ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################