| 摘要 |
PURPOSE:To improve characteristics of semiconductor element through realization of reduction in number of manufacturing steps and high integration density by forming the graft base region with self-alignment to the emitter region and base region and through reduction in noise by covering the junction surface of the emitter and base regions with the oxide film. CONSTITUTION:An oxide film 22 is formed by oxidizing the substrate 21 providing the n type Si layer forming the collector contact region 20 and the photo resist film 25 is formed by stacking the BSG film 23 and thin film 24. An aperture 26 is formed by etching and an aperture 27 is formed laterally and uniformly by over-etching the BSG film 23. Then, the oxide film 28 is formed on the Si substrate surface of aperture 27. At this time, the graft base diffusion layer 29 is formed. When the base diffusion layer 30 is formed by ion implantation, the base damage region 32 is formed. When the base region 30' and graft base region 29' are formed by the thermal treatment, the emitter diffusion layer 31 is formed by the ion implantation. At this time, the emitter damage region 33 is formed. Then, the emitter region 31' is formed by thermal treatment. The surface of junction area between the emitter region 31' and base region 29' is covered with the oxide film 28 not containing impurity. |
