| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve reliability of the connection of an NSMD(non-solder mask defined) package to a motherboard. SOLUTION: An NSMD semiconductor package is equipped with a pad electrode 4 and a solder resist opening 6, which are both nearly circular, where the pad electrode 4 is smaller than the solder resist opening 6, and the plane center C1 of the solder resist opening 6 deviates from the plane center C2 of the pad electrode 4. A solder bump 11 is formed by surface tension of molten solder applied to the pad electrode 4, whereby a contacting part P1 where the bump 11 comes into contact with the circumference of the opening 6 and a noncontacting part P2 are produced. Impurities, such as flux or the like left between the solder resist opening 6 and the solder bump 11, is easily discharged out by cleaning through the non-contacting part P2 that is open, and a connection between a semiconductor package and a motherboard can be improved in reliability.</p> |
