Bipolar transistor with base drive circuit protection
AssigneeNissan Motor Co., Ltd.
InventorTetsuya Hayashi
Life of this patent
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Abstract
An n+ type emitter region and a p-type base region are formed in contact with one main surface of an n-type collector region, a p-type cathode region is formed in a ring shape in contact with the main surface so as to enclose the emitter region and the base region, the potential at the cathode region is sustained at a level equal to the potential at the emitter region and a p-type guard ring region is formed in a ring shape so as to enclose the cathode region. This structure prevents the base drive circuit from becoming damaged by an avalanche breakdown current.
Claims8
A semiconductor device with base drive circuit protection having a semiconductor substrate of a first conduction type, with a collector region, an emitter region and a base region being formed on one main surface of the semiconductor substrate, including:
- a cathode region of a second conduction type different from the first conduction type that is formed at said main surface and is not in contact with either said emitter region or said base region, wherein said cathode region achieves a potential equal to the potential at said emitter region and is formed in a ring shape so as to enclose said emitter region and said base region and so as to being contact with said collector region.
Dependencies are inferred from the claim text.