Active matrix substrate and manufacturing method thereof

An active matrix substrate comprising:

• a gate electrode deposited on an insulating substrate;
• a gate insulating film deposited on said gate electrode;
• a semiconductor layer deposited on said gate insulating film;
• a source electrode and a drain electrode which are deposited on said semiconductor layer;
• and
• a transparent conductive layer including portions deposited on said source electrode and said drain electrode to take substantially the same patterns as those of said source and drain electrodes, said transparent conductive layer is connected to either said source electrode or said drain electrode and constitutes a pixel electrode.

An active matrix substrate comprising:

• a gate electrode deposited on an insulating substrate;
• a gate insulating film deposited on said gate electrode;
• a semiconductor layer deposited on said gate insulating film;
• source and drain electrodes deposited on said semiconductor layer;
• and
• an ITO film deposited on said source and drain electrodes to include a portion having substantially the same pattern as that of said source and drain electrodes.

A display device comprising:

• a thin film transistor structure formed on an insulating substrate;
• a pixel electrode formed to be connected to either a source electrode or a drain electrode of said thin film transistor structure;
• a data line formed to be connected to either the source electrode or the drain electrode of said thin film transistor structure;
• and
• a gate line formed to be connected to a gate electrode of said thin film transistor structure,
• wherein an upper surface of an upper electrode among said source, drain and gate electrodes of said thin film transistor structure is covered with an ITO film, and an upper surface of either said data line or said gate line is covered with a gate insulating film.

A method for manufacturing an active matrix substrate in which a source electrode, a drain electrode, a semiconductor layer, a gate insulating film and a gate electrode are sequentially deposited on an insulating substrate directly or indirectly, comprising the steps of:

• patterning a gate metal deposited on said gate insulating film by the use of a resist mask;
• patterning said gate insulating film and said semiconductor layer by using said patterned gate metal as a mask;
• forming an ITO film and patterning the ITO film by using a resist mask;
• and
• patterning said gate electrode by using said patterned ITO film as a mask.

A method of manufacturing an active matrix substrate comprising the steps of:

• forming a pattern of a gate electrode on an insulating substrate;
• sequentially depositing a gate insulating film and a semiconductor layer on said gate electrode and then forming a metal film;
• depositing an ITO film in consideration of a pattern of said metal film to be patterned and in consideration of a pattern of a pixel electrode;
• and
• patterning said metal film by using said ITO film as a mask thus forming a source electrode and a drain electrode.