Attached is the HASL thickness requirements that were in a Jim, Attached is the HASL thickness requirements that were in a Lucent X-Spec many years ago. These thickness requirements were really more in line of what HASL was capable of providing if you controlled the process rather than requirements of what we wanted. Since this X-Spec was first written there has been a little more control (but not much) to the HASL process. If anything, rather than control I believe what occurred is they would blow a little harder to make sure the HASL was thin for fine pitch surface mount. You know the old choices in electronics (Cost - Quality - Speed pick any two of the three) Well the big problem I see with HASL is that you can only have a choice of one out of two (Thin or Solderable pick only one). Regards, George George M. Wenger Andrew Wireless Solutions Senior Principal FMA / Reliability Engineer 40 Technology Drive, Warren, NJ 07059 (908) 546-4531 (office) (732) 309-8964 (cell) [log in to unmask] -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Guy Ramsey Sent: Wednesday, August 20, 2008 8:01 AM To: [log in to unmask] Subject: Re: [TN] Maximum HASL thickness for SMT of QFN R&D Assembly is a subsidiary of R&D Circuits. Our facility is located in Allentown PA. Circuits is in South Plainfield NJ. I can't answer your question. About a year ago Circuits relocated, expanding from a 10,000 sqft building into a 26,000. I don't think they have turned on the HASL equipment since the move. It isn't often they fabricate a board suited to the finish. -----Original Message----- From: James Verrette [mailto:[log in to unmask]] Sent: Tuesday, August 19, 2008 4:58 PM To: [log in to unmask] Subject: RE: [TN] Maximum HASL thickness for SMT of QFN Guy, Since it looks like you work for a PCB fabricator. Do you know what is your typical target mean and std deviation for the surface thickness of SnPb HASL process? Thanks, Jim -----Original Message----- From: Guy Ramsey [mailto:[log in to unmask]] Sent: Tuesday, August 19, 2008 3:49 PM To: 'TechNet E-Mail Forum'; James Verrette Subject: RE: [TN] Maximum HASL thickness for SMT of QFN I would not recommend HASL, choose one of the flat alternative finishes. Remember type 3 paste is about 50% solder by volume. A 100 um of variation in the HASL is more than the total applied volume of solder in the paste deposit. This type package will not work well with 100% variation in solder volume in the solder connection. You might be successful with 25 um of variation in the HASL finish. -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of James Verrette Sent: Tuesday, August 19, 2008 1:22 PM To: [log in to unmask] Subject: [TN] Maximum HASL thickness for SMT of QFN What is the maximum SnPb HASL thickness/uniformity that can be tolerated in the SMT assembly of a .5mm pitch QFN package? Is there anyone else out there putting .5mm pitch parts on HASL finished boards that is willing to share their experiences? Jim Senior Electrical Engineer --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 ----------------------------------------------------- No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.138 / Virus Database: 270.6.6/1621 - Release Date: 8/19/2008 6:53 PM ------------------------------------------------------------------------------------------------ This message is for the designated recipient only and may contain privileged, proprietary, or otherwise private information. If you have received it in error, please notify the sender immediately and delete the original. Any unauthorized use of this email is prohibited. ------------------------------------------------------------------------------------------------ [mf2] --------------------------------------------------- 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 -----------------------------------------------------