Design and development challenges for micro chip carrier

The development of size and cost-effective leadframe based packages to replace conventional packages such as TSSOP or TQFP with the same or better package integrity and electrical performance is critical for penetration of future wireless subscriber applications. In this report, the development of a 0.9 mm thick MO-208 thin fine pitch plastic quad flat no lead package (5×5 mm, 28 leads, 0.5 mm pitch) with moisture sensitivity level (MSL) 1 reliability is discussed. Technical challenges for the development of package MO-208, called micro chip carrier in ASE Korea, are to control the mechanical impact on leads after mold array packaging (MAP) and to reduce the die stress with leadframe design based on various simulation processes. No mechanical impact on the leads after molding has been found to be a critical factor for control of the package integrity and to increase the lifetime of saw blades. It was also discovered that the package under development is able to achieve JEDEC MSL 1 reliability criteria. This paper discusses the package and process development performed in order to meet these new wireless subscriber application requirements. Benchmark and internal evaluation supported our approaches and our micro chip carrier (MCC) technology is very competitive