A method for manufacturing a heat sink miniaturizes the heat sink by improving the heat exchange efficiency per unit area. A photosensitive film is formed on the heat sink(10) base material made of the metal. The photosensitive film is processed by a mask pattern corresponding to the desired heat sink shape. A penetration hole(13) is formed by wet-etching the heat sink base material exposed from the photosensitive film. The photosensitive film is removed from the heat sink base material in which the penetration hole is formed. A plating layer is formed on the whole surface of the heat sink base material including the inner wall of the penetration hole. A diamond-like carbon layer(30) is formed on the plating layer by coating the whole surface of the heat sink base material with diamond like carbon to fill the penetration hole.
