| 摘要 |
PURPOSE:To enhance the gain band width product fr and to reduce the irregularity of hFE by providing an ion implanted region in a base region, thereby generating a drift electric field. CONSTITUTION:An epitaxial layer 22 is grown on a substrate 21. At this time, the lower diffusion of a buried layer 23, a collector region 25 and an elevational isolating region 24 are diffused elevationally, thereby forming the buried layer 23 having the prescribed width and the region 25. Subsequently, an ion implanted region 34 is formed. In other words, the surface of the layer 22 is selectively covered with a thick photoresist layer, and phosphorus ions are implanted on the surface of the base region 27 of the prescribed vertical P-N-P transistor. This ion implanted region 34 is formed near the center of the region 27, and formed deeper than the emitter region 28 without reaching the collector region 25. Thereafter, the upper diffusion of the region 24 and the collector introduction region 26 from the surface of the layer 22 are simultaneously diffused, the upper and lower isolating regions 24 are coupled to P-N isolate the layer 22. |
