| 摘要 |
PURPOSE:To constitute a fundamental logic circuit with a simple constitution by forming in the emitter layer branched regions each independently elongated to the surface of the emitter layer and having the opposite conductivity type to that thereof as a multibase. CONSTITUTION:On one surface of a P type semiconductor substrate 1, an N type semiconductor layer 2 is separated into island regions by a P type isolation region 3. A P type impurity region 4 is formed in one 2a of the island regions, forming a P-N junction surface between the region 2a as a collector region, the terminal portion of the P-N junction being exposed to the surface of the layer 2a. In the layer 4, an N type emitter layer 5 is formed. Moreover, in the layer 5, as a multibase independent branched regions are formed so as to extend over from the surface to the layer 4. In such a constitution, owing to a pinch effect the impurity region below the layer 5 between the regions 6a-6c presents an extremely high resistance, so that the regions 6a-6c can be regarded as disconnected from each other with respect to the operating level of a logic circuit. Thereby, a logic circuit can be simply constituted. |
