Hi Werner, We feel that the electroless copper is separating from the outer layer copper . I have attached an image. Hope it helps. rgds Pradeep > Hi Pradeep, > You do not give a sufficient description of the issue—what is separating > from what? > Werner > > > > > > > > > -----Original Message----- > From: Pradeep Menon <[log in to unmask]> > To: [log in to unmask] > Sent: Fri, Apr 2, 2010 2:11 am > Subject: [TN] Outer layer separation > > > Dear all, > > Wanted some inputs on a problem which we are facing currently > > We observe a separation, rather tendency for separation, on 2.5mm thick > MLB boards when subjected to 3X 288 deg 10 sec thermal stress. This is > mostly found only on one side ie in one of the outerlayers, and very few > on both outer layers. The inner layers are intact. > > We use N4000-6 as well as 4000-13EP laminates for fabricating PCBs and we > use laminate construction for the stack up. We do Plasma desmear followed > by a run thru permanganate too. We tried various parameters in drilling as > well as reviewed all the basic electroless / electroplating parameters , > and all were found as desired. > > We use 1-1.2 microns thick electroless copper followed by a flash > electrolplated copper of about 12 microns before pattern printing. The > board is then pattern plated to achieve a minimum PTH copper of 30 > microns. > > Looking forward fro ur inputs > > Rgds > > Pradeep > > > > > > > ______________________________________________________________________ > This email has been scanned by the MessageLabs Email Security System. > For more information please contact helpdesk at x2960 or [log in to unmask] > ______________________________________________________________________ > > --------------------------------------------------- > Technet Mail List provided as a service by IPC using LISTSERV 15.0 > 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/contentpage.asp?Pageid=4.3.16 > for > additional information, or contact Keach Sasamori at [log in to unmask] or > 847-615-7100 ext.2815 > ----------------------------------------------------- > > > = > > ______________________________________________________________________ > This email has been scanned by the MessageLabs Email Security System. > For more information please contact helpdesk at x2960 or [log in to unmask] > ______________________________________________________________________ > > --------------------------------------------------- > Technet Mail List provided as a service by IPC using LISTSERV 15.0 > 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/contentpage.asp?Pageid=4.3.16 > for additional information, or contact Keach Sasamori at [log in to unmask] or > 847-615-7100 ext.2815 > ----------------------------------------------------- > > ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------