Integrated Copper Heat Slugs and EMI Shields in Panel Laminate (LFO) and Glass Fanout (GFO) Packages for High Power RF ICs

摘要

This paper demonstrates, for the first time, ultra-thin, panel laminate fan-out (LFO) and glass fan-out (GFO) packages with embedded copper heat spreaders and electromagnetic shields for packaging high-power RF ICs in much smaller form factors and at potentially much lower cost than current ceramic and metal flange packages. This unique double-sided package addresses the thermal dissipation requirements of 30-100W power amplifiers by bonding the IC directly to a large copper heat spreader embedded in the substrate, using high thermal conductivity die-attach paste. It also addresses the RF, microwave and mm-wave performance requirements by utilizing low-loss tangent glass and polymer dielectrics, as opposed to lossy epoxy dielectrics or mold compounds. The combination of glass and high temperature polymers also enables superior harsh environment reliability with built-in stress buffer layers to mitigate the CTE mismatch induced stresses from large copper thermal structures.