| abstract |
A semiconductor device including a gate structure and a spacer structure is provided. The semiconductor device includes: a first active region and a second active region; an insulating layer between the first active region and the second active region; a first gate structure on the first active region and the insulating layer, the first gate structure having a first end on the insulating layer; a second gate structure on the second active region and the insulating layer, the second gate structure having a second end portion facing the first end portion in the first direction, the second end portion being on the insulating layer; and a separation structure located between the first and second ends and extending into the insulating layer. The partition structure includes a lower portion, a middle portion, and an upper portion, the middle portion having a maximum width in the first direction greater than a maximum width of the lower portion in the first direction, and the middle portion having a maximum width in the first direction greater than a maximum width of the upper portion in the first direction. |