| 摘要 |
A low-noise transistor comprising a cutoff region (38; 47) laterally surrounding the emitter region (36; 45) in the surface portion of the transistor and of such conductivity as to practically turn off the surface portion of the transistor, so that the transistor operates mainly in the bulk portion. In the NPN transistor, the cutoff region is formed by a P ring (38) in a P<-> type well region (35), and, in the PNP transistor, by the N<+> type enriched base region (47) between the emitter region (45) and the collector region (49). <IMAGE> |
