| 摘要 |
PURPOSE:To enable to bring the impurity density distribution within the range of desired impurity density by a method wherein, after gallium has been diffused in the prescribed depth on an N type silicon layer, boron is diffused and a press-in oxidation is performed subsequently. CONSTITUTION:First, gallium Ga is diffused in the prescribed depth on an N type silicon layer. At this time, said diffusion is performed in such a manner that it will be lower than the target impurity density distribution. Then, boron B diffusion only is performed for the purpose adjusting characteristics. Subsequently, the target impurity density distribution is formed and adjusted in the vicinity of peak density by performing oxidation by push-out diffusion. The original impurity density distribution of gallium Ga is affected by the diffusion performed for said adjustment of impurity density distribution, but the degree of this affection is very small can be neglected. |
