A thin film transistor substrate includes a gate electrode arranged on a substrate, a gate insulation layer arranged on the gate electrode, an active pattern arranged on the gate insulation layer, a source electrode overlapping a first end portion of the active pattern, and a drain electrode overlapping a second and opposite end portion of the active pattern. A fluorocarbon-like material is arranged on one or more of surfaces of at least one of the active pattern, the source electrode and the drain electrode, and on a photoresist pattern used in the formation process of the thin film substrate. The fluorocarbon-like material on the photoresist pattern serves to maintain a shape and size of the photoresist pattern during subsequent patterning processes.