A transistor, a display driver integrated circuit having the transistor, and a method for fabricating a transistor are provided. A transistor, according to example embodiments, may include a substrate with a device active region defined by an isolation layer, wherein the device active region may include a source active region, a channel active region, and a drain active region and the channel active region may include a pair of edges contacting the isolation layer. The transistor, according to example embodiments, may also include a gate electrode overlapping the channel active region, wherein the edges are exposed beyond a periphery of the gate electrode, a gate dielectric between the gate electrode and the channel active region, and source and drain impurity regions within the source and drain active regions.