Semiconductor devices

A semiconductor device, comprising:

• an active pattern on a substrate, the active pattern extending in a first direction parallel to an upper surface of the substrate;
• a gate structure on the active pattern, the gate structure extending in a second direction parallel to the upper surface of the substrate and crossing the first direction;
• channels spaced apart from each other in a vertical direction perpendicular to the upper surface of the substrate, each of the channels extending through the gate structure;
• and
• a through contact extending through the substrate and the active pattern, the through contact including a lower portion and an upper portion sequentially arranged in the vertical direction;
• wherein a width in the second direction of the lower portion of the through contact decreases as the distance in the vertical direction from a lower surface of the substrate increases, and a width in the second direction of the upper portion of the through contact increases as the distance in the vertical direction from the lower surface of the substrate increases.

A semiconductor device, comprising:

• an active pattern on a substrate, the active pattern extending in a first direction parallel to an upper surface of the substrate;
• a gate structure on the active pattern, the gate structure extending in a second direction parallel to the upper surface of the substrate and crossing the first direction;
• channels spaced apart from each other in a vertical direction perpendicular to the upper surface of the substrate, each of the channels extending through the gate structure;
• an insulating interlayer on the active pattern and the gate structure;
• and
• a through contact extending through the insulating interlayer and the substrate, the through contact commonly contacting sidewalls in the first direction of the channels, and an upper portion and a lower portion of the through contact contacting each other and formed of the same material.