| 摘要 |
PURPOSE:To prevent the deterioration of characteristics by isolating an insulator region surrounding the side surface section of an MISFET and source-drain regions and forming an insulator region coating the bottom of the MISFET. CONSTITUTION:An insulator region 3 is formed on the inside opposite to the main surface of a semiconductor substrate 1 through a method such as ion implantation, and the semiconductor layer 1 consisting of the same substance as the substrate 1 is grown in an epitaxial manner. An insulating film 18 is shaped, and an n type well region 4 and a p type well region 5 are formed selectively through ion implantation or impurity diffusion. The insulating film 18 is oxidized selectively, and insulator regions 2 are formed so as to surround the well regions 4, 5. MISFETs are shaped in the well regions 4, 5. Accordingly, source- drain regions for the MISFETs can be isolated from the insulator region 3, and the deterioration of characteristics by unequal crystal structure on the formation of the insulator region 3 can be prevented. |
