| abstract |
The subject of the present invention is to provide a lead frame, which is a lead frame in which only the upper surface is plated with silver as the outermost layer of the upper surface, the side surface, and the lower surface of the lead frame base material, which can reduce cost and operating time. The productivity is improved, while the thickness of the entire plating layer including the silver plating layer is suppressed to be thin, and the adhesion to the sealing resin is significantly improved. The solution is to provide a roughened silver plating layer (11) with needle-shaped protrusion groups as the outermost plating layer on the upper surface, side surface, and lower surface of the lead frame base material (10) made of copper-based material. The roughened silver plating layer has a crystal structure in which the ratio of crystal orientation <101> is the highest among the ratios of crystal orientations <001>, <111>, and <101>. |