| 摘要 |
PROBLEM TO BE SOLVED: To change the shapes of burying members and to facilitate burying of an element isolation insulating film by a method wherein in the section in the depth direction of a groove formed in the surface of a semiconductor substrate, the relation of the sectional areas of the upper part of the groove and the part near bottom of the groove to the radius of curvature of the circular form of the groove makes smaller the upper part than the part near the bottom. SOLUTION: A trench (groove) 15 of an aspect ratio of 10 or more to 1 is formed in a silicon substrate 11 and a colored insulating film 16 is formed from the sidewall of the upper part of the trench. The shape, which is located at a position lower than the film 16, of the trench 15 is formed into a circular form, which is a form of a radius of curvature of the minimum value larger than that of the radius of curvature of a square form, and the sectional area in the depth direction of the trench is large. An n<+> heavily doped diffused layer 17, which is used as a capacitor electrode, is formed on the inner surface of the trench 15 by impurity diffusion from a vapor phase. Moreover, an arsenic- doped amorphous silicon film (burying member) 19, which is used as a storage electrode, is buried-formed in the interior of the trench 15 via a capacitor insulating film (burying member) 18. |
