| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a multi-layer wiring board capable of improving the strength of the board at a low cost. <P>SOLUTION: A plurality of terminal pads 27 for mounting an IC chip 31 are provided on a main surface 12 of a coreless wiring board 10, and a plurality of pads 41 for BGA (ball grid array) for electrical connection with an external board are provided on a rear surface 13. On the coreless wiring board 10, a solder resist 42 is formed so as to cover the rear surface 13, and a resin-made reinforcing plate 50 is fixed in a plane contact state on the solder resist 42 via an adhesive layer 51. Openings 45, 52, 53 are formed on positions corresponding to the pads 41 for BGA on the solder resist 42, the reinforcing plate 50 and the adhesive layer 51. The diameters of the opening 45 of the solder resist 42 and the opening 52 of the reinforcing plate 50 are set to be smaller than the diameter of the opening 53 of the adhesive layer 51. <P>COPYRIGHT: (C)2010,JPO&INPIT |
