Hi Jim, We did dye penetration testing of plastic BGAs a few years ago (see "Reliability of Ball Grid Array Packages in an Automotive Environment", Proc. Surface Mount International, 1997, pp. 85-92). The trick is to let the solder creep when you remove the package. We achieved that by gluing a steel hook on top of the package with a high-strength epoxy (make sure that the surface is clean before you apply the glue) and a weight of 10 kg was then attached to the hook, applying a vertical pull force. With time, sometimes for several hours, and in some cases with a little help from elevating the temperature to approximately 85 degree C, all BGAs could be removed in a consistent way. Hope this will help you. Please contact me if you want to discuss it further. Per-Erik Tegehall IVF SWEDEN Phone: +46 31 706 61 48 Fax: +46 31 27 61 30 Email: [log in to unmask] > ---------- > > As part of our BGA reliability testing we would like to perform dye > penetration testing of some of our BGA solder joints (typically after > they've seen vibration and/or thermal stress tests.) > > I've seen references to dye penetration tests being done (and even > photo's of joints); what I am looking for is a reference to a person > that actually has done this. We've tried and frankly are having > difficulties (with plastic BGAs) "popping off" the BGA to look at the > solder joint. Typically, we tend to fail at the interface between the > substrate (sometimes the PWB, sometimes the interposer) and the pad > rather than in the solder joint. Now this happens EVEN on parts that > have gone through extensive life testing (thermal cycle/shock) and > gone "open". We've cross sectioned some parts and the solder joints > (many of them) are in fact cracked. > > I have a feeling there is a "technique" to this and I want to talk > first hand with a person that's "got the touch". > > Thanks for your assistance. > > -------------------------------------------------------- > Jim Maguire > Boeing Phantom Works > E/E M&P > Phone (253)657-9063 > Fax (253)657-8903 > email: [log in to unmask] > --------------------------------------------------------- > --------------------------------------------------------- > Jim Maguire > Boeing Phantom Works > E/E M&P > (253)657-9063 > email: [log in to unmask] > --------------------------------------------------------- > > ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################