Madhu, Have you checked your artwork(films) with a densitometer. Your d-min, d-max may be off which would mean you have a photoplotting/ film developing problem. ----- Original Message ----- From: "S.R. Madhuchandra" <[log in to unmask]> To: <[log in to unmask]> Sent: Wednesday, November 05, 2003 7:19 AM Subject: Re: [TN] Scum ring or Ring Mask on pad > Dear Franklin, > > Please find the answers for your comments > > 1 - Tack drying is as per the specification provided by the Lacquer > supplier. > In order to check for over curing, we cured panelsfor more time than > specified and washed off the mask with out exposing. The developability of > the mask was good and no solder mask residue was seen on the > pads ( With this could we suspect the Exposing process to create the > problem?) > > 2 - Checked the vacuum and found to be with in the specification. > I feel if the vacuum problem is there, the outer part of the ring > must have the mask on pad and not the inner ring. Your coments on this? > > 3 - Developing - The developer temp has been increased to 35 deg C > Chemistry has been changed > Dwell time and pressuer is maintained as per specification. > > Madhu > > > > |---------+-----------------------------> > | | Franklin D Asbell | > | | <fasbell@NETWORKCI| > | | RCUITS.COM> | > | | Sent by: TechNet | > | | <[log in to unmask]> | > | | | > | | | > | | 10/29/2003 08:03 | > | | PM | > | | Please respond to | > | | "TechNet E-Mail | > | | Forum."; Please | > | | respond to | > | | Franklin D Asbell | > | | | > |---------+-----------------------------> > >--------------------------------------------------------------------------- ---------------------------------------------------| > | | > | To: [log in to unmask] | > | cc: (bcc: S.R. Madhuchandra/NAN/ATS/IN) | > | Subject: Re: [TN] Scum ring or Ring Mask on pad | > >--------------------------------------------------------------------------- ---------------------------------------------------| > > > > > What do you mean by excessive drying? do you mean final cure? By the time > the panel gets to dry (either post-develop drying, or final cure) there > should not be any mask there at all...if you're talking drying after copper > plate (leaving moisture or residuals) then again, this would cause adhesion > issues...your comments are puzzling... > > Franklin > > --------------------------------------------------- > Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 > for additional information, or contact Keach Sasamori at [log in to unmask] or > 847-509-9700 ext.5315 > ----------------------------------------------------- > > > > Scan by AT&S virus protection > > --------------------------------------------------- > Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 > ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------