| 摘要 |
<p>A semiconductor device according to the invention comprises: a first semiconductor layer having a low impurity concentration formed on a semiconductor substrate; a second semiconductor layer of a first conductivity type formed on the first semiconductor layer and forming a heterojunction therewith; an emitter region and a collector region formed in the first and second semiconductor layers; and a semiconductor region of a second conductivity type formed in at least the second semiconductor layer between the emitter region and the collector region, wherein two-dimensional electron gas layers, induced in portions of the first semiconductor layer adjacent to the heterojunction and between the emitter region and the semiconductor region and between the collector region and the semiconductor region, are used as current paths, and a virtual base region is formed in the first semiconductor layer below the semiconductor region by majority carriers injected from the semiconductor region into the first semiconductor layer by forward biasing the emitter region and the semiconductor region, thereby enabling a bipolar transistor operation.</p> |
