Triode structure field emission display device using carbon nanotubes and method of fabricating the same
A field emission display device and a method of fabricating the same are provided. The field emission display device may include a substrate, a transparent cathode layer, an insulation layer, a gate electrode, a resistance layer, and carbon nanotubes. The transparent cathode layer is deposited on the substrate. The insulation layer is formed on the cathode layer and has a well exposing the cathode layer. The gate electrode is formed on the insulation layer and has an opening corresponding to the well. The resistance layer is formed to surround the surface of the gate electrode and the inner walls of the opening and the well so as to block ultraviolet rays. The carbon nanotube field emitting source is positioned on the exposed cathode layer.
1. A method of fabricating a field emission display device which has a triode-structure composed of an cathode layer formed on a substrate, an insulation layer formed on the cathode layer such as to have a well, and a gate electrode formed on the insulation layer such as to have an opening corresponding to the well, the method comprising:
(a) depositing a resistance layer for blocking light on the surface of the gate electrode and the inner wall of the well and patterning the resistance layer to expose the cathode layer at the bottom of the well;
(b) depositing a protective layer on the resistance layer so as to surround the insulation layer and the gate electrode and patterning the protective layer such that the protective layer remains only on the tops of the insulation layer and the gate electrode;
(c) depositing carbon nanotube paste such as the carbon nanotube paste covers the protective layer and fills the well and the opening;
(d) radiating light at the rear of the substrate to expose the carbon nanotube paste to the light and performing development to lift off non-exposed carbon nanotube paste and the protective layer, thereby forming a carbon nanotube column; and
(e) firing the carbon nanotube column to lower it and performing surface treatment, thereby forming a field emitting source in which carbon nanotube tips protrude from the surface of the carbon nanotube column.
2. The method of claim 1 , wherein the protective layer is a dry film release (DFR) film.
3. The method of claim 2 , wherein in step (d), the non-exposed carbon nanotube paste and the protective layer are simultaneously lifted off.
4. The method of claim 3 , wherein in step (d), the non-exposed carbon nanotube paste and the protective layer are simultaneously lifted off using a solution of sodium hydroxide.
5. The method of claim 2 , wherein in step (d), the non-exposed carbon nanotube paste is first removed using a developer, and the protective layer is lifted off.
6. The method of claim 5 , wherein the non-exposed carbon nanotube paste is removed using a solution of Na 2 CO 3 .
7. The method of claim 5 , wherein the protective layer is removed using a solution of sodium hydroxide.