| 摘要 |
<p>PROBLEM TO BE SOLVED: To accurately position and fix ball bumps for electronic component by forming three-dimensionally recessed electrode pads. SOLUTION: On an outer layer conductor 3 laid on the top surface of a wiring board 1, electrode pads 6 each having a recess at the center are formed three-dimensionally, corresponding to the locations of ball bumps 15. The conductor 3 is for mounting electronic components 30. A conductive paste 38 such as a cream solder is coated or filled in the recessed electrode pads 6, the ball bumps 15 of the components 30 are fitted in the pads, and the solder is reflowed for connecting them to conductor circuits of the board 1. On a multilayered wiring board 2 blind through-holes 9 formed between the top surface outer layer conductor 3 and nearest inner conductor 8 may be used as the recessed pads 6 where the ball bumps 15 of the components are mounted in the through- holes 9.</p> |
