Andrew, I came across X-ray laminography 8 years ago when I attended an AOI seminar. It detects open , bridge and cracked solder joints by 3D imaging and non-destructive method. Now, HP makes 5DX digital laminography machines (formerly, Four Pi system). I was told HP sells these machines by pounds since each weights a couple of tons. Here is a link to get you started with digital laminography. http://www.dgzfp.de/pages/tagungen/berichtsbaende/bb_67-CD/bb67_v11.pdf thanks Matthew S. Park Vansco Electronics. >>> [log in to unmask] 5/30/2006 9:23:52 AM >>> Good Morning Technetters, I have been reading this forum for some time now and have thoroughly enjoyed learning from group (including the lesson on good and bad puns). I am hoping that the collective wisdom can help me out again. We are a manufacturer of embedded computer boards for the military industry. As a result, these board tend to be fairly complex, very dense, and very expensive. Some of our boards are conformally coated and the BGA components are underfilled. The conformal coat is removable with solvent and the underfill is reworkable at solder rework temperatures. My problem is failure analysis of the solder balls that may be embedded in the underfill. Thusfar, we have not had a significant problem, but I am still stuck with the dilemma of how to analyze a solder joint problem without destructive cross-sectioning of the very expensive PCB assembly. On boards without underfill/conformal coat, we have had good success in many cases with optical imaging under the BGA package (Ersascope). On the underfilled boards, we have tried acoustic imaging and several X-ray systems, but none seem to provide the resolution necessary to determine a possible solder joint problem. Due to the cost of these assemblies and our need to provide the utmost in product reliability, I would like to consider any means of analyzing a suspect solder joint, without having to cross sectioning the board unless I know that there really is a solder joint problem (as opposed to a component or PCB/HDI problem). I was wondering if any Technetters have come upon a similar problem and found a solution. Thanks! Andrew Shieh --------------------------------------------------- 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 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- 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 847-615-7100 ext.2815 -----------------------------------------------------