Integrated Circuit Devices Including FIN Active Areas with Different Shapes

An integrated circuit device can include a substrate having a first area and a second area and a pair of first fin-shaped active areas each having a first shape protruding from the first area in a first direction, adjacent to each other, and extending in a straight line. A fin separation insulating film can be between the pair of first fin-shaped active areas in the first area and a second fin-shaped active area can protrude from the second area in the first direction and have a second shape that is different from the first shape, wherein respective widths of each of the pair of first fin-shaped active areas are less than a corresponding width of the second fin-shaped active area.