An array substrate includes first and second lines on a substrate and formed of a metallic material; a gate electrode connected to the first line; a gate insulating layer on the first and second lines and the gate electrode and including a groove exposing the substrate and positioned between the first and second lines; a semiconductor layer on the gate insulating layer and corresponding to the gate electrode; a data line crossing the first and second lines and on the gate insulating layer; a source electrode connected to the data line; a drain electrode spaced apart from the source electrode; a passivation layer on the data line, the source electrode and the drain electrode and including an opening, the opening exposing the gate insulating layer and the drain electrode; and a pixel electrode positioned on the gate insulating layer and in the opening and contacting the drain electrode.