| 摘要 |
PURPOSE:To decrease thermal damage on wafer by forming a silicon oxide film on the first impurity vacuum-deposited layer formed in the specified region of a silicon substrate in such a manner as it is partly in contact with the vacuum- deposited layer, vacuum-depositing a second impurity thereon and thereafter diffusing the first and second impurity. CONSTITUTION:A base impurity layer 2 is formed by depositing base impurity to the specified region of a silicon substrate 1. Next, an SiO2 layer of the emitter forming area is removed from the SiO2 layer 3 including base impurity and an SiO2 layer 4 not including impurity is further formed. Thereafter, an emitter impurity is deposited on the SiO2 layer 4 not including impurity, an emitter impurity layer 5 is formed and base emitter impurity diffusion is then carried out. In this diffusion process, the base impurity of base impurity layer 2 diffuses into the silicon substrate 1, but the emitter impurity of emitter impurity layer 5 diffuses first into the SiO2 layer and thereafter reaches the substrate surface of silicon substrate 1. Then, the emitter diffusion diffuses into the silicon substrate 1, forming the emitter. |
