| 摘要 |
PURPOSE:To obtain a resin-sealed type device of excellent heat radiation characteristic by determining the position of a heat radiation plate in a sealed metal mold using at least four projections provided on the heat radiation plate. CONSTITUTION:Projections 5, 6 are provided at four positions of a heat radiation plate 1 to determine the position of the heat radiation plate in a metal mold at the forming of resin. The accuracy of the interval (i) between the bottom surface of the heat radiation plate and the lower surface of the projection 6 is determined by the press accuracy of lead frame machining and is approx. + or -0.01mm.. When a semiconductor pellet 3, a metal thin wire 4 and the front and the back surfaces of the heat radiation plate 1 are covered with resin 7, the dispersion of the resin thickness (t) under the heat radiation plate is approx. 0.25- 0.27mm. and the dispersion of the heat radiation characteristic is reduced. Consequently, the thickness of the resin under the heat radiation plate can further be made thinner. The heat radiation plate 1 is connected with the parts A, B of a lead frame and after resin forming, the parts A, B are cut and separated together with a lead wire 2. |
