Semiconductor memory device with a ring-shaped bit line

摘要

The invention relates to a semiconductor memory device in which a bit line ring which functions as a bit line is formed at the upper and lower stage of the bit line and a storage node is formed to be overlapped in the same direction with said bit line formed perpendicularly to a word line to improve the integration degree. Therefore, a capacitor area can be increased without an increase of an area of the unit cell to improve the integration degree of a semiconductor memory device and the generation of the bent portion of the active region can be avoided to decrease the distortion.