Comparative Study on Mechanical and Thermal Performance of eWLB, M-Series™ and Fan-Out Chip Last Packages

Abstract

In recent years, Fan-Out (FO) packages have become widely used in handheld, mobile consumer and internet of things (IoT) devices. FO packaging enables a greater I/O density as well as multiple components in the same package. Several types of FO packaging are offered in the market today, for example; embedded wafer level BGA (eWLB), M-Series™ as well as a flip chip based structure referred to as Fan-out Chip-Last Package (FOCLP) The work compares the mechanical and thermal performance of the three types of FO packages. Finite element analyses were carried out to examine mechanical performance metrics, including warpage, stress in the extreme low-k (ELK) interconnect and board level solder joint reliability. Thermal simulations were completed to compare the thermal dissipation differences among the FO package types. The paper concludes with a summary of the advantages and disadvantages of the different FO structures studied.