I am looking at the possibility of making boards with electroplated tin finish (tin over copper). From the experiments I've done so far with tin finished boards there exists a problem with tin slivers after etching. This same problem agrees with what people have mentioned in a couple of past posts on IPC TechNet forum regarding tin as the final finish. Etching undercut is unavoidable and therefore slivers will always be around. I am interested to know if people are successfully making such boards and if so what are they doing to minimize this problem. Some of the ideas are: 1) Follow with a solder reflow stage to remove the slivers 2) tin plate at minimal thickness so the slivers are too week to be supported and fall off during normal etching and rinsing cycles. Practical minimum plating thickness is about 1 um (40 micro inches). This idea doesn't sound very good going by what I hear about copper/tin migration and the poor solderability that can result over a period of time. 3) go over each board with a nylon brush and hope that no problematic slivers remain to cause shorts sometime down the track. I am just starting out with PCB fabrication and trying to learn more about the industry. Please excuse me for asking such basic questions. Adam Seychell --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------