| 摘要 |
PROBLEM TO BE SOLVED: To obtain an element isolation structure which is not affected by the misalignment of a mask nor deviated exposure focusing, by providing element isolating regions having third insulating film areas between first and second insulating films and between and on second and fourth conductive films between trench capacitors. SOLUTION: Trench capacitors are obtained by forming second and third conductive films 12 and 13 in trenches and completely burying a conductive film 17 between the trenches. Since the third conductive films in the two adjacent trenches do not come into contact with a semiconductor substrate 1, but are sufficiently isolated from the substrate 1, the volumes and contacting areas of the second and third conductive films 12 and 13 can be secured in the greatest states. Therefore, such an element isolating region that is not affected by the misalignment of a mask nor deviated exposure focusing can be formed by covering the whole surfaces of the trenches with a mask material used for forming the element isolating region. |
