| 摘要 |
PURPOSE:To acquire a silicon planar type semiconductor device having a structure whose depletion layer easily grows uniformly and resists external effect by forming the device of a first semiconductor layer of first conductivity type, a second semiconductor layer of second conductivity type, an insulating film, a conductive ring, a first main electrode and a second main electrode. CONSTITUTION:When a reverse voltage is applied to a main junction 4 between main electrodes 8, 9, a depletion layer grows from the main junction 4 and a guard ring 5 and a channel stopper 6 work to hold a reverse voltage of a main junction flat part 4a. In the process, a conductive ring 12 positions on an n<->-silicon layer 2 as a first semiconductor layer through an insulating film 7. Furthermore, since each conductive ring 12 is spaced regularly to a p-region 3, it does not have a detrimental effect on operation of the guard ring 5 and a channel stopper 6. When irregular electric charge exists inside an insulating film 7 below an insulating film-silicon interface and the conductive ring 12, electric charge easily moves inside the conductive ring 12 to cancel effect of irregular electric potential as electric potential of each conductive ring 12 is fixed; therefore the conductive ring 12 resists irregular charge. A depletion layer easily grows uniformly in this way. |
