A strategy for forming robust adhesion with the substrate in a carbon-nanotube field-emission array

A method of how to form a strong adhesion of carbon nanotubes (CNTs) to substrate by introducing an intermediate metal layer in fabricating spray-based field emitters and its effect to the field-emission properties were addressed. An Indium or tin layer was deposited on an indium-tin-oxide glass substrate and thermally annealed to hold the CNTs tightly. This underlying metal layer forms a strong bond to CNTs by wetting while melting without any detectable evaporation of metal atoms. This gave rise to a stable field-emission current at high voltage, which was confirmed by a mass spectrometer. The tube density and field-emission characteristics strongly depend on the annealing temperature of metal layers.