| 摘要 |
A method for manufacturing a base of a pressure mount type semiconductor device which has a base body of electrically and thermally conductive metal material and a cylindrical wall integrally and vertically provided on the top of the base body and adapted to engage a pellet pressurizing member so that the pellet pressurizing member is restrained from its upward movement, the base body being integrally provided with an annular projection of weldable material which is used to projection weld to the base on the upper surface, a shell to cover a semiconductor pellet on the base and with a stud to be threaded later. In this method, a metal blank which comprises a lower metal layer of electrically and thermally conductive material having a relatively large thickness and an annular upper metal layer of copper-nickel alloy having a relatively small thickness and secured to said lower metal layer on the upper surface is prepared and then deformed by extrusion so as to form the annular projection from the upper metal layer and to form the cylindrical wall and the stud from the lower metal layer. |
