Abstract
The development of noncontact IC cards is in a rapid progress toward their practical use. A process of connecting an IC chip with antenna wires poses problems from viewpoints of mass productivity and antenna characteristics. The present paper proposes a method of laser soldering of antenna wires for noncontact IC cards : fluxless laser soldering that consists of heating a copper wire with an Nd : YAG laser beam and pressing it onto the chip and solder bump successively. Comparing with the conventional pulse heat method, some advantages are confirmed : shorter soldering time and maintenance-free operation. The soldered part shows a good wettability and a sufficient tensile strength of 3.64MPa.
