An active matrix addressing LCD device having an active matrix substrate on which conductive lines are formed is provided, which suppress the AI hillock without complicating the structure of the lines and which decreases the electrical connection resistance increase at the terminals of the lines, thereby improving the connection reliability. The device comprises an active matrix substrate having a transparent, dielectric plate, thin-film transistors (TFTs) arranged on the plate, and pixel electrodes arranged on the plate. Gate electrodes of the TFTs and scan lines have a first multilevel conductive structure. Common electrodes and common lines may have the first multilevel conductive structure. Source and drain electrodes of the TFTs and signal lines may have a second multilevel conductive structures. Each of the first and second multilevel conductive structures includes a three-level TiN/Ti/Al or TiN/Al/Ti structure or a four-level TiN/Ti/AI/Ti structure. Each of the TiN film of the first and second structures has a nitrogen concentration of 25 atomic % or higher. The Al file may be replaced with an Al alloy.