To provide an ultrasonic flip chip mounting method exhibiting high connection reliability by reducing adverse effect of ultrasonic vibration onto a semiconductor chip.

Bumps 207 are formed on the electrodes 205 of a semiconductor chip 204, the bumps 207 are aligned with electrodes 105 of a circuit board 104, and then a pressing force and an ultrasonic vibration are applied to the bonding face in order to perform face down bonding. In such a flip chip mounting method, an organic resin film 213 is formed on one side of the semiconductor chip 204 where the bumps 207 are formed with such a thickness as the forward end of the bumps 207 projects, the organic resin film 213 is cured, foreign matters adhering to the forward end part of the projecting bumps 207 are removed, and then the bumps 207 are bonded to the electrodes 105 of the circuit board 104.