| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To improve the reliability as a circuit board, by suppressing the impairment of a dielectric strength resulting from an opening part of a metal plate. <P>SOLUTION: The circuit board is provided with the metal plate 1 having the opening part 2 as a core member, and the opening part 2 is arranged so that the size gradually increases toward the upper surface side from the lower surface side. Wiring patterns 5, 7 are arranged through insulating layers 4, 6 in the both surface sides of the metal plate 1, respectively. The insulating layer 4 and the wiring pattern 5 in the upper region of the opening part 2 are arranged so that the upper faces are depressed. Moreover, in order to connect each wiring pattern electrically, a conductor part 10, which penetrates the metal plate 1 through the opening part 2, and connects the wiring pattern 5 and the wiring pattern 7, is arranged. Further, an LSI chip 11 is connected directly with the upper surface side of the metal plate 1 through a solder ball 12. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
