Wireless IC device and manufacturing method thereof

A wireless IC device comprising:

• a radiation plate;
• a wireless IC chip;
• and
• a substrate on which the wireless IC chip is mounted, the substrate being provided with a feed circuit, the feed circuit including at least one of a resonant circuit or a matching circuit, the at least one of the resonant circuit or the matching circuit including an inductance element, the feed circuit being electromagnetically coupled to the radiation plate;
• wherein
• the substrate is made of a resin material and includes a recess in a first main surface thereof;
• the substrate is provided with a wiring electrode arranged along a bottom surface of the recess, the wiring electrode being electrically connected to the feed circuit;
• the substrate is provided with a wedge member made of a different material from that of the resin material, the wedge member extending between the bottom surface of the recess and a second main surface of the substrate so as to be spaced apart from the wiring electrode;
• the wireless IC chip is mounted in the recess and coupled to the wiring electrode.