The invention provides a package with an improved semiconductor device heat transfer structure including a semiconductor integrated circuit chip mounted on a substrate, a package for receiving the semiconductor integrated circuit chips mounted on the substrate, a radiator being attached to the package for radiation of a heat to an exterior and for sealing the package and a foil which made of a heat conductive material has corrugations having top portions in contact with the chip and bottom portions in contact with the radiator for transferring the heat from the semiconductor integrated circuit chip to the radiator.