| 摘要 |
<p>PURPOSE:To cut down the silver consumption notably while providing the silver with excellent bond properties onto a lead frame by a method wherein, after forming a film with excellent bond properties to a silver on the whole surface of a lead frame, partial silver plated layers are formed on the ends of a multitude of inner leads to be wire-bonded. CONSTITUTION:A copper base raw material lead frame composed of a tab 16, a multitude of inner leads 14 with their ends approaching to the tab 16, a multitude of outer leads 10 comprising outer terminals and connecting parts connecting the inner leads 14 to the outer leads 10 is prepared and after forming a film 26 with excellent bond properties to silver on the whole surface of the lead frame, partial silver-plated layers 24 are formed on the ends of said multitude of inner leads 14 to be wire-bonded. Finally, a semiconductor pellet 18 is bonded onto said tab 16 while one ends of wires 22 are bonded to the electrode part of the pellet 18 and the outer ends to the ends of said inner leads 14 to seal said inner leads 14, semiconductor pellet 18, tab 16 and wires 22 with a package 28.</p> |
