| 摘要 |
PROBLEM TO BE SOLVED: To provide a printed circuit board, in which the connecting strength of the bottom of a via is strengthened, without thickening the entire circuit pattern in a via-on-pad structure. SOLUTION: A lower layer circuit pattern 16, including a connecting pad 6, is formed on the main surface of a core substrate 11, a via hole bottom strengthening pad 7 is formed on this connection pad 6, and a via hole 5 reaching the via hole bottom strengthening pad 7 is formed on an interlayer insulating film 10. An upper-layer circuit pattern 14 is formed on the inner surface of the via hole 5 and the interlayer insulating film 10 through electrolytic plating or electroless plating, the electrode pad 4 of the upper-layer circuit pattern 14 is connected to the via hole bottom strengthening pad 7 through the via hole 5, the electrode pad 4 exposed to the opening formed in a protective film 9 is covered with a solder bump 3, and the electrode 2 of a CSP 1 of the electronic part for a semiconductor device, etc. is connected to the solder bump 3. COPYRIGHT: (C)2004,JPO&NCIPI |
