| 摘要 |
PURPOSE:To facilitate mounting a high output semiconductor device and reduce a pitch between leads or a width of a lead and facilitate application to a multiposition package and a miniature package by a method wherein a tab and lead wires are made of different materials and the tab is made of the material with high thermal conductivity. CONSTITUTION:Leads 4' are made of material whose tensile strength is more than 60kg/mm<2> and a tab 3' is made of material whose thermal conductivity is more than 0.2cal/cm.sec. deg.C. Iron system alloy material such as 42 alloy (Fe-42% Ni)or Kovar (Fe-29% Ni-17% Co) can be used as the material for the lead and copper system alloy such as tin copper alloy (Cu-0.1-8% Sn) or iron copper alloy (Cu-0.1-3% Fe) can be used as the material for the tab. A lead frame 10 is composed of the tab 3' and the leads 4' which are formed independently by stamping and jointed together by spot welding. A semiconductor device 2 is mounted on the tab 3' with a junction layer 5 made of silver paste between and the junction layers 5 provided on the tips of the inner lead portions 4a of the leads 4' are connected to the semiconductor device 2 by bonding wires 7 and the semiconductor device 2 and the inner lead portions 4a are molded with sealing resin 6. |
