Radio frequency identification tag device

PROBLEM TO BE SOLVED: To provide a radio frequency(RF) identification tag device with which mass production is enabled at reduced cost by providing an antenna element with a wire, connected through a wire bond connection to a connecting part on a semiconductor, and encapsulating it with a cover made of an organic substance. SOLUTION: An antenna 133 connected to a semiconductor circuit 111 on a substrate 141 is formed of 1st and 2nd wires 131 and 132 having connecting terminals connected to and opening terminals disconnected from 1st and 2nd connecting parts 121 and 122 by wire bond connections. Then, lengths 162 and 163 of wires 131 and 132 are determined corresponding to the frequency of RF signal to be transmitted. Besides, the circuit 111, the antenna 133 and the substrate 141 are encapsulated by a cover made of an organic substance 151. Thus, an RF identification tag device 100 can be produced from daily utensil materials at reduced cost while enable mass production. In this case, it is preferable that the lengths of wires 131 and 132 are equal and a wavelength is the 1/4 wavelength of the frequency of a signal.