Latest Technologies of Epoxy Molding Compound (EMC) for FO-WLP

FO-WLP is used for RF etc. for mobile as a package excellent in low profile, low warpage, cost reduction, electric performance etc. and this market is expanding since it began to be used in Application processer (AP) in 2016. It is expected that adoption to AP for mobile will continue to grow and further expansion to other products is also expected. Meanwhile, Epoxy molding compound (EMC) for FO-WLP is required to have functions not found in EMC for low-end packages. For example, since the molding area is large and the molding thickness is thin, if a conventional EMC is used, the warpage becomes large after curing and it cannot proceed to the subsequent process. In order to control warpage after curing, it is important to reduce cure shrinkage of EMC. In addition, in order to fill completely the gap between flip chip bumps of large size chip, control of filler size, melt viscosity etc. is more severely required.