PMV (Plating Mold Via) interconnection development in molded SiP modules

Abstract

Recently, there are increasing demands of a size reduction and a fine interconnection technology, especially for System-in-Package (SiP) module and Package on Package (POP) module in a smart phone and a wearable electronic device. In this study, we presented the Plating Mold Via (PMV) interconnection technology as an innovative fine pitch interconnection solution between substrate I/O pads and package I/O pads in molded System-in-Package (SiP) modules. Similar to the Through Mold Via (TMV), the laser mold via process is first performed to produce a through-via in the Epoxy Mold Compound (EMC) mold, but plating and Soldering process are used simultaneously to produce the metallurgical interconnection to embody the I/O pins of the over-molded surface. After the PMV technology is described, a study of PMV in the molded packaging module is followed. The study is conducted using a test vehicle of SiP module that contains flip chips, Quad Flat Non-leaded (QFN) packages and passives. It is focused on several interface reliability issues, including the interfacial strength of PMV to substrate metal pad as well as to the laser projected area of EMC, and the study of IMC at the plating metal and solder interfaces. The study clearly shows that the PMV technology is a promising fine pitch interconnect solution for various SiP modules.