| 摘要 |
PURPOSE:To greatly simplify the manufacture of molded transistors, by tightly fitting silver leaves on the tips of lead parts of a lead frame by heat, brazing transistor substrates on the leaves, sealing up the substrates and the leaves and cutting off the lead parts from the lead frame. CONSTITUTION:A silver ribbon 13 is unwound from a reel 12 and cut off to a prescribed length so that silver leaves 14 are prepared. The leaves are placed on the lead parts of a lead frame 1 made of tin, aluminum, zinc or the like which is easy to remove a corrosion product film from the surface and which is anticorrosive. The frame 1 is set on a hot block 15 to heat the coupled parts 11 of the frame under an inert gas 16 such as N2. The silver leaves 14 are positioned on the heated coupled parts 11 by using a vacuum attraction collet 17 and then tightly fitted on the coupled parts by heat. Transistor substrates 5 are brazed on the silver leaves. Electrodes on the substrates are connected by a metal 6 to the leaves 14 on the coupled parts 11b, 11c for emitters and bases. The substrates and the leaves are sealed up with an epoxy resin or the like. The lead parts of the lead frame are cut off from its longitudinal part, thereby obtaining individual transistors. |
