Singapore– 29 July 2014 – STATS ChipPAC Ltd., a leading provider of advanced semiconductor packaging and test services, today announced new quality benefits for fan-in wafer level packaging made possible by its encapsulated Wafer Level Chip Scale Package (eWLCSP^TM) solution. The combined benefits of superior quality, lower cost structure and the ease of conversion through a drop-in replacement have led to a strong demand for eWLCSP^TM and an accelerated adoption across its customer base.  

An intrinsic feature of eWLCSP^TM is the thin polymer casing formed on the back and four sidewalls of the die, providing mechanical robustness and resistance to chipping, cracking and handling damage as well as improved long term reliability compared to traditional bare die WLCSP. Mechanical damage has been an ongoing quality concern for WLCSP technology, necessitating special processes such as back side coating and additional inspection steps to manage outgoing quality and ensure a defect free product. As the industry transitions to more advanced silicon (Si) node products, the fragile, exposed Si structure in traditional WLCSP is expected to become an even greater concern. These issues are addressed with eWLCSP technology.

“WLCSP is a compelling solution for space constrained mobile devices and new applications such as wearable technology. With the added inspection costs and quality issues that customers face with bare die packaging, there is a clear and immediate need for a more robust WLCSP solution. The molded eWLCSP offers just that,” said Dr. Han Byung Joon, Executive Vice President and Chief Technology Officer, STATS ChipPAC. “Instead of managing quality through inspection, customers now have the opportunity to build quality into their product by design.” 

The encapsulation material that is a natural part of STATS ChipPAC’s FlexLine^TM manufacturing process is used to form the protective polymer casing for the eWLCSP package. This provides mechanical and optical protection for the bare die, both during shipping and handling as well as socket insertion for electrical test. In addition to eliminating localised damage such as chipping and cracking, eWLCSP provides a measurable increase in overall component strength. Bulk mechanical testing of eWLCSP has revealed an increase in component break strengths of more than 50% over traditional WLCSP structures.

Dr. Han continued, “While the reconstitution approach inherent to eWLCSP manufacturing has brought down the cost of eWLCSP below standard WLCSP, significantly lower costs can be realised with the use of a large panel format. The additional prospect of improved mechanical robustness with built in quality and a low risk, seamless conversion path from standard WLCSP has made the eWLCSP^TM an even more compelling value proposition.”