| 摘要 |
PURPOSE:To improve turn-OFF characteristics by forming a high impurity- concentration n-type region as surrounding a region superposing to an (n) emitter region in an (n) base layer while shaping another gate electrode being in contact with one part of the n-type region. CONSTITUTION:A p base layer 13 is formed through a diffusion from the upper surface of an n-type silicon board 1, an n<+> region 4 is shaped through a selective diffusion from a lower surface when an n emitter layer 14 is formed onto the whole surface through the diffusion from an upper surface, and a (p) emitter layer 11 is laminated onto a lower surface through an epitaxial method. The (p) base layer 13 surrounding the (n) emitter region and the N<+> region 4 at the central section of the lower surface are exposed through selective etching, and a cathode electrode 3 and an anode gate electrode 6 are each shaped. Excess carriers stored n the (p) base layer 13 by main currents are lead out by gate currents from the cathode gate electrode 3 while excess carriers stored in an (n) base layer 12 are drawn out by anode gate currents from the anode gate electrode 6. Accordingly, turn-OFF characteristics are improved. |
