| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve whisker resistance of external plating. <P>SOLUTION: A semiconductor device comprises a tab on which a semiconductor chip is fixed; a plurality of inner leads; a plurality of outer leads 2b formed integrally with the inner leads; a plurality of wires connecting an electrode pad of the semiconductor chip and the inner leads; and a sealing body sealing the semiconductor chip. Outer plating 8 made of lead-free plating is formed on a surface of each of the plurality of outer leads 2b projecting from the sealing body. In the outer plating 8, the number of particles with a diameter of 1 μm or less existing in an interface side 8c in the thickness direction is larger than the number of particles with a diameter of 1 μm or less existing in a surface side 8d in the thickness direction. Therefore a difference in a linear expansion coefficient between the particles and the outer lead 2b of the outer plating 8 is reduced and whisker growth can be suppressed. <P>COPYRIGHT: (C)2012,JPO&INPIT |
