Patent ID: 6844622

Claim:
A semiconductor package with a heat sink, comprising: a chip carrier; at least one chip mounted on a surface of the chip carrier and electrically connected to the chip carrier; a heat sink having a first surface, a second surface opposing the first surface, and a plurality of side surfaces interconnecting the first surface and the second surface, wherein the first surface of the heat sink is attached to the chip for interposing the chip between the chip carrier and the heat sink; an interface layer formed on the second surface of the heat sink, and made of a material having adhesion with a molding compound smaller than adhesion between the heat sink and the molding compound, wherein the interface layer covers the entire second surface of the heat sink; and an encapsulant made of the molding compound for encapsulating the chip, tho heat sink and the chip carrier, wherein the interface layer and the side surfaces of the heat sink are exposed to outside of the encapsulant, the side surfaces of the heat sink are flush with side edges of the encapsulant, and the molding compound left on the interface layer during formation of the encapsulant is easily and thermally removable from the interface layer, so as to make the semiconductor package free of flash of the molding compound because of the relatively smaller adhesion between the interface layer and the molding compound and a difference in thermal expansion coefficient between the interface layer and the molding compound.