An integrated circuit device includes: a fin-type active area protruding from a substrate, extending in a first direction parallel to an upper surface of the substrate, and including a first semiconductor material; an isolation layer arranged on the substrate and covering a lower portion of a sidewall of the fin-type active area, the isolation layer including an insulation liner conformally arranged on the lower portion of the sidewall of the fin-type active area, and an insulation filling layer on the insulation liner; a capping layer surrounding an upper surface and the sidewall of the fin-type active area, including a second semiconductor material different from the first semiconductor material, and with the capping layer having an upper surface, a sidewall, and a facet surface between the upper surface and the sidewall; and a gate structure arranged on the capping layer and extending in a second direction perpendicular to the first direction.