| 摘要 |
<p>[PROBLEMS] To provide a circuit device manufacturing method by which downward warping of a wiring board is suppressed even in an existing reflow furnace, without arranging a special supporting part on the lower plane of the wiring board. [MEANS FOR SOLVING PROBLEMS] A cream solder (23a) is applied on the upper plane of a wiring board (1A), a circuit module (2) is mounted on the wiring board through the cream solder, the wiring board is carried into a reflow furnace (40) while supporting the both end sections of the wiring board in the width direction, and the circuit module (2) is bonded on the upper plane of the wiring board (1A) by reflow soldering. The wiring board (1A) is a resin multilayer board wherein a plurality of resin layers are stacked by having prescribed wiring patterns in between, and the total area of the wiring patterns (11a, 11b, 12, 13) on the upper plane side is set larger than the total area of the wiring patterns (11c, 11d, 14) on the lower plane side, to the center plane of the wiring substrate (1A) in the thickness direction. Thus, downward warping of the wiring board (1A) is suppressed by using thermal expansion of the wiring patterns.</p> |
