A reliable low cost assembly technology for 0201 compatible QFN, X3 Thin QFN

Electronics devices nowadays, especially the portable consumer devices like notebooks, GPS, multimedia players, digital cameras, camcorders, cellular phone handsets and accessories, are increasingly driving product demand and technological developments. Each succeeding product generation is expected to be smaller and lighter in weight, driving the needs of miniaturization technologies. There are several options available for such technologies. This paper shall focus on one of the most cost effective and good reliability options, a sawn QFN package, using almost the same infrastructure as a typical leadframe based package assembly line, where it does not require totally new assembly technologies or unestablished production technologies or material. The process flow and process development methodologies for key areas are described. The criteria adopted for materials selection of these areas are also outlined in detail. Finally, results of full reliability testing and qualification of MSL1/260 are presented.