Semiconductor Devices Including Channel Regions with Varying Widths

A semiconductor device includes a semiconductor substrate, a fin-type structure on the semiconductor substrate, and a gate on a portion of a top surface and portions of two side surfaces of the fin-type structure. The gate has a first width at a first level from the top surface of the substrate and a second width at a second level from the top surface of the substrate that is lower than the first level. The first width is greater than the second width, and a width of the gate is reduced from the first width to the second width between the first level and the second level.