A method of fabricating a liquid crystal display device includes forming a first active layer on a substrate, forming a first gate insulating film on the first active layer, forming a first gate electrode on the first gate insulating film, forming a first interlayer insulating layer on the first gate electrode, forming a pixel electrode on the first interlayer insulating layer, forming at least one insulating film to cover the pixel electrode, forming a first plurality of contact holes in the first interlayer insulating layer and the at least one insulating film, the first plurality of contact holes including a first source contact hole to expose a first source area of the first active layer and a first drain contact hole to expose a first drain area of the first active layer, forming a pixel contact hole in the at least one insulating film to expose the pixel electrode, performing a hydrogenating treatment to the substrate including the first source contact hole, the first drain contact hole, and the pixel contact hole, and forming a first source electrode contacting the first source area of the first active layer, and a first drain electrode contacting the direct drain area of the first active layer and connected to the pixel electrode.