Abstract: Disclosed in the present invention is a method for fabricating a triode-type field emitter, the method comprising the steps of: growing carbon nanotubes on a substrate using semiconductor-processing technology; coating an insulating material, particularly SOG (Spin-On-Glass), on the substrate having the carbon nanotubes grown thereon; drying the coated insulating material; and cutting the coated insulating material with a grinder to uniform height so as to control the height of the carbon nanotubes. According to the present invention, the following advantages are obtained: (1) the insulation between the carbon nanotubes and the substrate can be achieved so as to prevent leakage current, (2) the damage of the carbon nanotubes in the polishing step, (3) the adhesion between the carbon nanotubes and the substrate is maintained, (4) the field emission stability of the field emitter is improved.

Abstract: The present application is directed to a method for synthesizing carbon nanotubes using magnetic fluid by thermal chemical vapor deposition. The method includes the steps of producing a catalytic metal using the magnetic fluid, coating the produced catalytic metal on a substrate, and thereby synthesizing carbon nanotubes.