JPS55134957A - Semiconductor device - Google Patents

Abstract

PURPOSE:To obtain an IC suitable for a watch or the like by forming a buried source of a static induction transistor logic semiconductor (SIT) by As diffusion, and a buried collector of a pnp transistor by p diffusion, with the outward diffusion much encoraged. CONSTITUTION:P of a large diffusion constant, which is used for the buried layer 11 directly below a p-type base 8 of an npn transistor, is allowed to accumulate on a substrate, with the diffusion depth into the substrate and concentration previously controlled, and outward diffused during epitaxial growth in order to make the distance 12 to the base 8 a desired value. On the other hand, As of a small diffusion constant is used for a buried layer 2, since a large outward diffusion of the buried source 2 of a SIT hinders a depletion layer 10 from diffusion, so that capacitance is increased and speed is lowered. Thus, the saturation voltage between the collector and emitter of the npn transistor is permitted to lower without damaging characteristics of the, high speed and little power consumption of SIT, so that an IC suitable for a watch or the like can be obtained.