A semiconductor device includes: a semiconductor substrate; a power device formed in the semiconductor substrate; a metal bilayer formed over the semiconductor substrate, the metal bilayer including a discontinuous metal layer formed on and in contact with a continuous base metal layer; and one or more contact pads formed in the metal bilayer or in a metallization layer above the metal bilayer. The discontinuous metal layer includes a plurality of metal blocks which are laterally spaced apart from one another and which form a heat sink structure over the power device. The continuous base metal layer is configured to laterally spread heat energy from the power device to the plurality of metal blocks. Methods of producing the semiconductor device are also described.