| 摘要 |
PURPOSE:To prevent the destruction of a semiconductor device to be caused by overvoltage by a method wherein a diode region having shallow diffusion depth is formed surrounding a base region formed by diffusion from the main surface of a collector substrate. CONSTITUTION:A P type base region 3 is formed by diffusion from the main surface of an N<-> type collector substrate 1. Duffusion is performed from the main surface thereof to form a diode region 5 of which one side is formed as to surround the base region 3 and the other side as to exist in the collector substrate 1. At this time, depth of diffusion of the diode region 5 is made shallower than the base region 3. Accordingly the same result can be obtained with the case when a protective diode is connected to a transistor by outside equipment, VCE of the transistor is limited by breakdown voltage of the diode, and withstand voltage of the transistor is enhanced. |
