| 摘要 |
PURPOSE:To control the auto-doping of impurities into an epitaxial growth layer easily by forming a plane of a buried layer buried between a semiconductor substrate and the epitaxial growth layer in a netty or plural insular shape. CONSTITUTION:B is introduced selectively into the P type Si substrate 1, the impurity diffusion layer 12 with a netty pattern or an insular pattern is formed, the N type Si epitaxial growth layer 3 is shaped, and the whole is thermally treated. Consequently, B in the impurity diffusion layer 12 is diffused into the epitaxial layer 3, a P type diffusion layer 14 is molded, and a P type diffusion layer 5 for forming an element is shaped so as to join with the layer 14. Accordingly, the concentration of B in the N type epitaxial growth layer through auto-doping can easily be controlled because the amount of impurities introduced into the substrate can be decreased. |
