Transistor having asymmetric channel region, semiconductor device including the same, and method of fabricating semiconductor device including the same

Abstract

According to embodiments of the invention, a transistor includes a semiconductor substrate having an active region. A channel trench is disposed to cross the active region. A gate insulating layer covers an inner wall of the channel trench. A gate pattern is disposed to fill the channel trench and to extend over a main surface of the semiconductor substrate. Source/drain regions having a first conductivity are disposed in the active region at both sides of the channel trench. A channel impurity region having a second conductivity is disposed beneath one of the source/drain regions to be in contact with at least a sidewall of the channel trench.