| 摘要 |
PROBLEM TO BE SOLVED: To provide a dynamic random access memory wherein a junction leak current can be reduced. SOLUTION: A cut layer 7a of a second conductivity type is provider only immediately below a trench isolation oxide film 5 in a semiconductor board 1. A punch through stopper layer 9 of a second conductivity type and a low concentration impurity diffusion layer 15 of a first conductivity type sandwiching the punch through stopper layer 9 are provided toward inside a board from a main surface of the semiconductor board 1. A pair of source/drain regions 12 of a first conductivity type of LDD structure containing a high concentration part and a low concentration part are provided in a main surface of the semiconductor board 1. |
