Plastic IC packages rely on a contiguous structure for efficientheat conduction from the chip to the surrounding environment. Anydiscontinuity within the package, such as an interfacial separation ordelamination, degrades the thermal efficiency of the package. Fourpackage types have been studied with respect to the thermal impact ofinterfacial delaminations; a 240 pin plastic Quad-Flat-Pack (PQFP), athermally enhanced 240 PQFP, a 28 pin Lead-on-Chip (LOC) package, and aplastic overmolded 388 Ball-Grid-Array (PBGA) package. Modeling foundwide variation in the sensitivity of the package to thermal degradationbased on package type and delamination location. The largest shifts(50%) were found in thermally enhanced packages. The results identifyinterfaces critical to thermal integrity. In addition to studying thethermal impact of delaminations, practices to thermally enhance the PBGApackage will be discussed
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