| 摘要 |
PURPOSE:To obtain a surface silicon layer having no oxide precipitate by outward diffusing remaining unnecessary impurity to be implanted due to ion implantation at the time of manufacturing an SOI structure by implanting light element ions. CONSTITUTION:An oxygen ion beam 4 is emitted to the surface of a silicon substrate 2, and a buried oxygen layer 6 is formed in the substrate. In this case, a layer 10 which contains a large quantity of oxygen upon damaging of emitting is formed between the layer 8 remaining on the surface and the layer 6, and the oxygen remains also on the layer 8. In order to remove the remaining unnecessary introduced oxygen, a hydrogen ion beam 12 is implanted as light element ions in the state that the substrate is held at high temperature. Thus, a surface silicon layer 14 having low oxygen density is obtained. An MOS transistor 16 is formed in the layer 14 on the surface of the thus processed substrate. |
