Fan having an impeller including a resin portion and a metal plate

A fan includes an impeller and a metallic base portion. The base portion is arranged to be in thermal contact with a heat source. The impeller includes a resin portion including a plurality of blades, and a metal plate. In addition, the metal plate includes a flat plate portion arranged below the blades. A lower surface of the flat plate portion and an upper surface of the base portion are arranged axially opposite to each other with a gap intervening therebetween. An axial dimension of the gap is arranged to be 200 □m or less at least at a portion of the gap. Heat of the heat source is transferred to the metal plate through radiation from the base portion. Then, an air current produced by the impeller absorbs the heat from the metal plate. The heat generated from the heat source is thus efficiently discharged to an outside.