| 摘要 |
PURPOSE:To reduce the collector resistance without deteriorating the characteristic of a transistor by a method wherein, after a collector has been formed on the surface of the first semiconductor substrate, one surface of the second semiconductor substrate is glued onto the surface of the first semiconductor substrate so that a semiconductor device can be formed on the other surface of the second semiconductor substrate. CONSTITUTION:The surface of the first p type semiconductor substrate 17 is doped with phosphorus or arsenic so as to form n<+> type diffusion layers 181, 182. Then, one surface of the second semiconductor substrate 19 of the same conduction type as that of the substrate 17 is glued onto the first p type semiconductor substrate 17. Then, a bipolar transistor 20, a p channel type MOS transistor 21 and an n channel type MOS transistor 22 are formed on the other surface of the second semiconductor substrate 19. Through this constitution, an epitaxial layer which is apt to cause a crystal defect is not used, and it is possible to reduce the collector resistance without deteriorating the characteristic of a transistor. |
