PURPOSE: To enable adjustment of resistance values without making the whole insulating substrate inferior by applying laser beams to an overlapping part between a lower layer electrode and an upper layer electrode so as to make the lower layer electrode and the upper layer electrode electrically conductive.

CONSTITUTION: A first resistor 15 is connected in parallel with a short-circuit while partially overlapping layer electrodes 12 and 13 on an insulating substrate 11. Also, an electrode 16 whose one part is parallel with the lower layer electrode 12 is formed, and a second resistor 17 whose one part overlap the electrode 16 is formed in series with the first resistor 15 between the electrode 16 and the lower layer electrode wiring layer 13. When trimming the first resistor 15 in the longitudinal direction of the lower layer electrode 12 from its end part, a laser beam is applied to the part that the lower layer electrode 12 and the upper layer electrode 13 overlap each other so as to selectively evaporate the varied layer 14 between both electrodes to open a hole and further they fuse the lower layer electrode 12 and the upper layer electrode 13 to make both electrically conductive. Hereby, the resistance can be adjusted without making the whole insulating substrate inferior.