A method for manufacturing a semiconductor device that includes mounting a semiconductor chip on a circuit board having an insulating substrate, a plurality of wiring layers arranged on the insulating substrate, and bumps formed on the wiring layers respectively, in which the bump is provided across a longitudinal direction of a corresponding one of the wiring layers so as to extend over regions on both sides of the wiring layer and contact a surface of the insulating substrate, without a stepped portion formed on a surface of the bump, and a cross sectional shape of the bump taken in a width direction of the wiring layer is such that a central portion is higher than both side portions. The method also includes connecting electrode pads of the semiconductor chip to the bumps, thereby achieving connection between the electrode pads of the semiconductor chip and the wiring layers via the bumps.