The disclosure provides a thin film transistor, an array substrate, and a method for fabricating the same. An embodiment of the disclosure provides a method for fabricating a thin film transistor, the method including: forming a gate, a gate insulation layer, and an active layer above an underlying substrate successively; forming a patterned hydrophobic layer above the active layer, wherein the hydrophobic layer includes first pattern components, and orthographic projections of the first pattern components onto the underlying substrate overlap with a orthographic projection of a channel area at the active layer onto the underlying substrate; and forming a source and a drain above the hydrophobic layer, wherein the source and the drain are located respectively on two sides of a channel area, and in contact with the active layer.