| 摘要 |
PURPOSE:To form diffusion layers having different carrier concentrations by two or more at the same time by a method wherein oxide films to act as the diffusion sources and having different impurity concentrations are formed by two or more on a substrate, and perform diffusion. CONSTITUTION:The oxide films 6, 7 of diffusion sources having different contents of impurities are formed in order respectively on the semiconductor substrate 3, and an oxide film 8 is formed thereon. The oxide film 8 carriers out the duty to protect the surface of the substrate, and to prevent the atmosphere of the semiconductor substrate 3 from diffusion of impurities when diffusion is performed. By thermally treating the semiconductor substrate 3 manufactured by this way in a vacuum or in inactive gas, impurities are diffused in the semiconductor substrate 3 from the oxide films 6, 7 of diffusion sources, and the diffusion layers 1, 2 having different carrier concentrations are formed respectively. |
