| 摘要 |
PURPOSE:To enable the fluctuation in potential of an isolated substrate to be avoided without deteriorating the rapidity of a semiconductor device by a method wherein a conductor layer connecting to one conductivity type semiconductor substrate is provided as if encircling an element region having an impurity region. CONSTITUTION:An insulating film 17, a p type Si semiconductor layer 18, an SiO2 film 22 and a PSG film 26 are successively formed on an Si underneath substrate 16 and then opening parts 26a are made in the films 26, 22. An Si film is formed and then etched away to leave SiO2 films 27 on the sidewalls of the opening parts 26a. B (b) ions are implanted in the semiconductor layer 13 on the bottoms of the opening parts 26a using the films 27 as masks to form ion implanted regions 19a. Poly Si films 20 are formed and then etched away to be left in the opening parts 26a while SiO2 films 29 are formed on poly Si films 20. Next, the PSG film 26 is removed and the conductor films 20 are formed into element isolating regions 73. The poly Si films are formed on the film 22 so as to be patterned into gate electrodes 23. Next, As ions are implanted in the layer 18 and then diffused to form S/D regions 24a, 24b. Finally, S/D electrodes 31a, 31b are formed into an element region 72. |
