Is there an IPC void size specification for PBGA's detected by transmission X-ray (we use Nicolett Systems). Our current guideline is- voids are acceptable only if they are smaller than 20% of the diameter of the solder ball. What is your criteria for acceptability? Do you have reliability data to support your specification? Has there been any published papers specifically on the effects of voids on the reliability of PBGA solder joints? Sincerely, Eric Fremd Process Developement Engineer Solectron Technical Center (408) 956-6194 [log in to unmask] *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * ***************************************************************************