| 摘要 |
PURPOSE:To obtain a MOSLSI which has high reliability and prevents parasitic channel from occurring between element regions by repeating the steps of forming a groove, ion implanting an impurity, ion implanting an impurity which has atomic number larger than the previous impurity and activating it, thereby forming channel cut regions. CONSTITUTION:A mask is formed on a p type silicon substrate 11, a groove 14 is formed, ions are implanted to the substrate in the bottom of the groove 14 to form a boron ion implantation layer 15, an impurity which has atomic number larger than the boron such as argon is ion implanted to the layer 15. Subsequently, the mask is removed, a heat treatment is performed to activate the boron ion implanted layer 15' to form high density p<+> type channel cut region 16 on the bottom and side of the groove 14. Then, an element isolating region 19 which has an isolating material 18 made of CVD-SiO2 is formed. Thereafter, a plurality of gate electrodes 20, a gate oxidized film 21, an n<+> type regions 22,... are formed on the substrate 11, thereby forming an n-channel MOSLSI. |
