PURPOSE: To surely and firmly join terminals using a necessary amount of solder without causing a 'bridge' phenomenon even if the space between the terminals is small by providing an engagement channeled portion in solder for joining terminal pins.

CONSTITUTION: An engagement channel 12 is provided in solder 10 and one terminal 1 is engaged in the channel 12 perpendicular to the solder 10 and the other terminal is disposed on the upper face of the engagement portion. When the terminals thus arranged are heated by a heating coil, a 'bridge' phenomenon will not occur even with a small space between terminals, and terminals are surely and firmly joined together with a necessary amount of solder.