| 摘要 |
PURPOSE:To obtain a bipolar transistor by a method wherein a layer which has same conduction mechanizm as a base region is provided on a region in which an element isolation layer to be built and next thereto isolation by providing a V shaped groove is performed and short circuiting between an emitter and a collector is eliminated and self-alignment effect is utilized. CONSTITUTION:On a p-type substrate 10 on which an n<+>-buried layer 14 is fabricated n-epitaxial layer 11 is laminated, and an Si3N4 mask 13 is formed on an SiO2 film 12. By B ion implantation and sequential sintering, a p-layer is fabricated to be diffused horizontally. Next thereto the SiO2 film 12 is perforated and a V shaped groove 16 is fabricated by anisotropic etching. The groove surface is oxidized and a polycrystalline Si is laminated, and an SiO2 film is formed by oxidization of the surface, and the Si3N4 film is removed. Next thereto a resist mask 17 is provided, and after B ion implantation the mask 17 is removed, and sintering is performed, and thus an base layer 18 is fabricated. Next thereto they are covered with the SiO2 film, and an emitter layer 19 is fabricated through P diffusion. By this constitution the base layer 18 at the side of a isolation layer is completed by the p-layer 15, and short circuiting between emitter and collector does not occur on formation of the emitter layer 19. Thus 1C of a bipolar element which has a V shaped isolation layer can be fabricated by self-aligning effect with ease and high yield. |
