| abstract |
A circuit board having lands provided on the top surface of the circuit board and the bottom surface of a recess formed in the top surface and a metal mask having a projection on the bottom surface thereof are prepared. Solder cream is applied to the lands using the metal mask. Then, chip components and a flip chip IC are placed on the solder cream, and the circuit board is put into a reflow oven where the solder cream is melted and solidified so that external terminals of the chip components are reflow-soldered on the lands on the top surface of the circuit board and solder balls of the flip chip IC are reflow-soldered on the lands on the bottom surface of the recess. |