High performance liquid epoxy encapsulant for advanced semiconductor package

LEE (liquid epoxy encapsulant) has been used in the electronic assembly industry mainly for COB (chip on board) applications in the past which do not require high performance reliability. Nevertheless, new package development has brought CDBGAs (cavity down BGAs), for example, such as tape-BGAs, metal-BGAs, and plastic BGAs, as well as flip chip applications in the market where high performance encapsulants are needed. Due to the unique configurations and requirements of these new packages, potting and underfilling processes have replaced transfer molding as the encapsulation method and the conventional EMC (epoxy molding compound) has been used on substrates (mainly organic and some ceramic) instead of a metal leadframe, and therefore low warpage is required. In addition, the reliability requirements of temperature cycling, thermal shock and moisture resistance which applied to conventional IC packages are also applied to BGA and flip chip applications. An advanced epoxy encapsulant system for potting and underfilling applications was developed to meet the stringent requirements of new semiconductor packages with excellent performance.