| 摘要 |
<p>PURPOSE:To enable an IC lead frame to be improved in external appearance, W/B properties, solder wettability, and reliability so as to enhance an assembly process in productivity by a method wherein art Ni or Ni alloy plating layer is provided to all the surface of the lead frame, and an Au plating layer is provided to the Ni or Ni alloy plating layer excluding the outer frame part of the lead frame. CONSTITUTION:An Ni or an Ni alloy plating layer is previously provided as an acid-resistant layer to all the surface of a lead frame 1 for the improvement of the frame 1 in acid-resistance before an Au plating layer 17 is formed. At this point, an Ni or Ni alloy plating layer 11 and an Au plating layer 17 are formed through such a manner that a required pattern is formed and them Au plating layer 17 is formed on the Ni or Ni alloy player 11 through Au plating excluding an outer frame 2 of the lead frame 1. Thereafter, the lead frame 1 is subjected to an Au strike plating process, if necessary. Finally, an excessive Au strike plating layer is removed off through separation for the formation of the lead frame 1.</p> |
