Semiconductor devices having plug contact holes extending downward from a main surface of a semiconductor substrate and methods of forming the same

摘要

According to some embodiments of the invention, semiconductor devices and DRAM cells have plug contact holes. Methods of forming the same include forming a channel-portion hole disposed in a semiconductor substrate. Lower portions of the plug contact holes between first and second word line patterns extend downward from the main surface of the semiconductor substrate, thereby reducing a contact resistance between plug patterns and electrode impurity regions. The DRAM cell having the plug contact holes can improve the current driving capability of a transistor and the refresh characteristics of a capacitor.