| 摘要 |
Contact pins are provided in a socket main body into which an IC package is accommodated and brought into electrical contact with connection terminals of the accommodated IC package. Each contact pin is formed of a plurality of layers obtained by laminating an underlying layer containing Ni and a surface layer successively on a conductive base material. Furthermore, the surface layer includes a first layer on an underlying layer side, and a second layer in contact with the connection terminals of the IC package. The first layer is formed of a plating layer of which a principal ingredient is a Pd-Ni alloy which is a material lower in diffusion speed of Sn than that of Pd, among materials into which Sn dissolves and diffuses by applying heat. The second layer is formed of a plating layer of which a principal ingredient is Ag which is a material lower in diffusion speed of Sn than that of the first layer. |
