Abstract: A semiconductor device includes a first isolation structure extending through an upper portion of a substrate and defining a first active region, a first gate structure on the substrate, and first source/drain regions at upper portions of the first active region adjacent to the first gate structure. The first isolation structure includes an upper isolation pattern structure and a lower isolation pattern. The upper isolation pattern structure includes a first isolation pattern and a second isolation pattern covering a sidewall of the first isolation pattern. The lower isolation pattern is formed under and contacting the upper isolation pattern structure, and a width of the lower isolation pattern is greater than a width of the upper isolation pattern structure.

Abstract: A semiconductor device includes a gate structure disposed on a substrate. The gate structure has a first sidewall and a second sidewall facing the first sidewall. A first impurity region is disposed within an upper portion of the substrate. The first impurity region is spaced apart from the first sidewall. A third impurity region is within the upper portion of the substrate. The third impurity region is spaced apart from the second sidewall. A first trench is disposed within the substrate between the first sidewall and the first impurity region. The first trench is spaced apart from the first sidewall. A first barrier insulation pattern is disposed within the first trench.

Abstract: A semiconductor device includes a gate structure disposed on a substrate. The gate structure has a first sidewall and a second sidewall facing the first sidewall. A first impurity region is disposed within an upper portion of the substrate. The first impurity region is spaced apart from the first sidewall. A third impurity region is within the upper portion of the substrate. The third impurity region is spaced apart from the second sidewall. A first trench is disposed within the substrate between the first sidewall and the first impurity region. The first trench is spaced apart from the first sidewall. A first barrier insulation pattern is disposed within the first trench.