To address pad cratering, a vexing problem in lead-free assemblies that is largely attributable to problems with the resin used to make a PCB (printed-circuit board), IPC-Association Connecting Electronics Industries has released IPC-9708, "Test Methods for Characterization of PCB Pad Cratering." The new standard provides three test methods that enable product developers to determine the best material for their application. "In the beginning, there wasn't much attention [paid] to these types of failures because they were almost unheard of," said Dr. Reza Ghaffarian, an engineer at NASA's Jet Propulsion Laboratory and the chair of the IPC SMT Attachment Reliability Test Methods Task Group that developed IPC-9708. He explained in a press release that as companies started getting products ready to ship, they began to realize they had a problem that was affecting not just one or two parts, but many. "These are catastrophic failures that are sometimes latent. The defect doesn't always show itself in testing," he said.
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