The method of manufacturing a semiconductor mounting object intermediate structure and a semiconductor device

PROBLEM TO BE SOLVED: To reform the warp of a circuit board and materialize stable connection reliability, by interposing a circuit board between plates A and B having openings corresponding to the positions where semiconductor elements A and B are to be mounted on both sides of the faces A and B of the circuit board, in a semiconductor mounting method which is used in the case of flip-chip- mounting semiconductor elements on both the face A and the face B of the circuit board. SOLUTION: Since the warp of a circuit board where semiconductor elements A and B are mounted is suppressed by providing an integrated structure of plate where a circuit board is interposed between the plates A1 and B2 having openings in the positions where the semiconductor elements A and B are to be mounted at the face A and the face B of the circuit board 3.