Heat sink of module with built-in IC

Disclosed is a heat sink of a module with a built-in integrated circuit (IC) including a circuit board formed with a plurality of first through holes extending from an upper surface of the circuit board to a lower surface of the circuit board, a metal-attached IC mounted to the lower surface of the circuit board and attached at an upper surface thereof with a metallic member, a first conductive material provided at the upper surface of the circuit board, the first conductive material filling the first through holes so that it is in contact with the metallic member, a module case adapted to receive the circuit board therein while including upper and lower cases made of a metal, and a depressed structure formed at the upper case and adapted to allow the first conductive material on the upper surface of the circuit board to be in contact with the upper case. By this configuration, a heat transfer path is formed which extends from the metal-attached IC to the module case via conductive materials, thereby allowing heat generated from the metal-attached IC to be efficiently outwardly discharged via the module case.