Abstract: Thermally conductive heat transfer bodies are included in plastic packages to extend from the die pad and/or circuit chip to or near the surface of the package. Leakage is prevented by encapsulating the heat transfer body in a thin film of plastic and/or by arranging the interface between metal and plastic to be elongated and convoluted. The heat transfer body is attached to the die pad and/or lead frame to stabilize the body during molding and to aid in thermal communication between the chip and the heat transfer body. Air cavities and EMI shielding are provided by caps secured to the lead frames.

Abstract: Solderable connections are formed in a grid array pattern on the surface of a plastic package by modifying conventional lead frame assemblies so that the outer ends of the leads terminate at the bottom surface of the package and forming solder pads or balls on the ends of the leads. Conventional lead frames are used and, after modification, are encapsulated using conventional plastic packaging techniques to form plastic packages with solderable terminal ends arranged in an interconnection array on one surface of the package.