We have been having some problems with a BGA device where we see ball fatigue (solder ball cracks) after temp cycling. We think it may be related to severe undercut of the solder mask. Does anyone have information on different solder mask foot profiles? How difficult is it to get a straight sidewall on solder masks? Are there any that are much better than others for this attribute? What would be the trade offs? You can contact me off line if you prefer. Steve Joy 503-696-2239 [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 web site (http://jefry.ipc.org/forum.htm) for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################