PURPOSE: To enable assigning more lead terminals where solderability between an integrated circuit and a printed board can be confirmed by providing the periphery of substrate with an irregular part and then providing it with an electrode terminal part.

CONSTITUTION: On the periphery of a substrate 1 on which a cold chip 96, etc., are mounted, protruded part 11 and recessed part 12 are formed, and, along the protruded/recessed parts 11 and 12, a terminal pattern 21 is formed. Then, into the terminal pattern 21, a lead terminal 31 containing a U-shape engagement part is inserted, and, it is heated with such heating means as infrared ray, and, the solder on the terminal pattern 21 which has been soldered in advance is melted, so that, the terminal pattern 21 and lead terminal 31 are tightly jointed together. Thus, where solderability between an integrated circuit and printed board 1 is confirmed, more lead terminals are assigned.