i read all the pre-clean and clean and post scrub and scrub - whole lotta scrubbing goin on!!!! just kidding folks. >From the experience in the pcb field over many years i have found out that sometimes cleaning is just a band-aid for processes which aren't maintained properly - or just outside the optimum operating parameters. proper neutralization after electroless copper and an anti-tarn - with forced air drying capabilities - is adequate for dryfilm lamination and exposing. CHECK pH OF ANTI-TARN - or get into worse trouble than when you started. LPI applications sometimes leaves a film behind on the surface of the exposed copper. {shops have used peroxide based tin-lead strippers in removing film - especially when using thermal cure soldermask prior to HASL} but usually the breakpoint on the developer is a little off ( seems no one checks these things such as breakpoints anymore - all look for solution contact ). then when skip occurs - it's zap that board again. a little preventative process capability check has always paid off in the long run - there's production and at some point - maitenance has to kick in. regards richard fudalewski Atotech Canada Ltd *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To subscribe/unsubscribe send a message <to: [log in to unmask]> * * with <subject: subscribe/unsubscribe> and no text in the body. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************