| 摘要 |
PURPOSE:To improve operability by a method wherein chips are bonded to a lead frame to which a plurality of supporting plates joined together are connected, connection of leads is conducted, and thereafter joining portions of the supporting plates are cut off and removed. CONSTITUTION:A transistor chip 11 is fixed on one main surface of a supporting plate 2 by solder, and the base electrode of the chip 11 and an external lead 3 as well as the emitter electrode thereof and an external lead 5, are connected together by internal leads 12 and 13 respectively. The chip 11 is coated with coating resin 14. A supporting plate joining portion 10 of a lead frame is cut off and removed by pressing so that a plurality of supporting plates 2 are isolated from each other, and the lead frame thus prepared is put in a mold for sealing with resin. Then, thermo setting epoxy resin is filled up under pressure in a cavity 18 through a gate 19. Clamping of the mold being released subsequently, the lead frame is removed from the mold, and a molded resin body 20 is subjected to heat treatment, while a tie bar 6 and a common connecting slender piece 7 are cut off and removed by pressing. By this method, positional difference of the supporting plates is lessened, the operation is facilitated, and the imperfect insulation can be prevented since the joining portions of the supporting plates are cut off and removed before these plates are placed in the mold. |
