Stitch-Bond-Shearing in Optoelectronic Devices, Caused by Lead-Free-Wave-Soldering – Do We Need Improved Wire-Bonding Methods?

This case study shows a typical example of a manufacturing-chain-induced reliability problem. All participants of the chain do their work within specifications, but, looking at the system level, severe reliability problems have been observed. In order to get back into the system-level process window, several corrective actions are possible. In this case, the most promising approach is an improvement of the stitch bond robustness, combined with a clear user specification.