| 摘要 |
PURPOSE:To enable a transistor to be stably prevented from surge voltages by obtaining a clip voltage independent of the variation of ambient temperature by a method wherein the distance on the surface of a collector is set shorter than the width of a depletion layer spreading from the collector-base junction of the transistor. CONSTITUTION:All of the part immediately under a P-region forming a base 4 are an original N<-> collector region 2; the clip voltage VA is electrically connected to an end of the base region 4 and to an N<+> channel stopper 12, and is determined by the lateral substantial distance l to a voltage control electrode 14 extended to an inner direction via passivation film 11, and by the specific resistance of the N<-> collector region 2. The electrode 14, on high-voltage impressing, comes into a positive voltage and then induces negative charges to the surface of the collector region 2 via passivation film 11, the insulation film; thus enabling the control of the spreading of a depletion layer. From this point, it becomes possible to vary the withstand voltage by varying the position of the electrode 14. |
