| 摘要 |
<p>PROBLEM TO BE SOLVED: To reinforce the perimeter of a semiconductor device and prevent reduction of yields due to process failures after mounting the semiconductor device, by using a flexible printed circuit board in which a reinforcing plate made from an insulating resin within a specified thickness range is stuck on the opposite side of a semiconductor device mounting surface. SOLUTION: In a flexible printed circuit board 2 for mounting a semiconductor device, a reinforcing plate made from an insulating resin is stuck in advance on the forming surface of a circuit pattern 7 opposite to the mounting surface of a semiconductor device 1, and formation of a reinforcing plate by molding after device mounting is not performed. A sheet made from a non-thermoplastic polyimide resin 10 and a thermosetting polyimide resin, or a sheet made from an epoxy resin reinforced with a glass fiber and the like is used as the reinforcing plate. The reinforcing plate is preferably 50μm to 500μm thick. If the thickness is thinner than 50μm, the strength of the reinforcing plate would be low and reinforcing effect would be insufficient. Also, if the plate is thicker than 500μm, the whole size of a semiconductor package would be too thick.</p> |
