Effects of bonding materials in screen-printing paste on the field-emission properties of carbon nanotube cathodes

Abstract

Relationship between field emission property and composition of carbon nanotube paste for large area cold cathode J. Vac. Sci. Technol. B 22, 1345 (2004 10.1116/1.1667514 Room-temperature fabrication of high-resolution carbon nanotube field-emission cathodes by self-assembly Appl.The effects of bonding materials in screen-printing paste on field-emission properties were investigated with respect to high-efficient carbon nanotube ͑CNT͒ cathodes. The materials used to bond the CNTs to the cathode were composed of an insulating glass frit and a conducting Ag paste. The dependence of the electrical conductivity of the CNT paste, bonding material, and CNT ink on the field-enhancement factor was investigated using the Fowler-Nordheim equation. The emission current from the CNT cathode as the result of an electron tunneling effect was increased with increasing ratio of the dielectric glass-frit fraction in the CNT paste. The larger emission current of CNT cathode containing insulating-bonding materials can be attributed to a combination of the increased effective height of the CNTs, which protrude over the film in the cathode, and an increased field-enhancement factor.

Field Emission and Application of Carbon Nanotubes

“…A temperature above the melting point of binder will boil binder and it will eventually coat CNT emitters. 30 If the temperature is too low, the binder did not melt, so they are unable to fix tubes on the substrate. In addition, the melting point of glass frit, commonly used inorganic binder, is above 450 • C. However, unfortunately, SWCNT burns near this temperature in air.…”

A High-Luminescence Fringelike Field Emission from Screen-Printed Carbon Nanotube and Zinc Oxide Composite Film

“…Firstly, the interspaces of CNTs were filled with ZnO grains and the CNT-ZnO film was formed a good conductive layer. The conductive bonding materials would result in low sheet resistance of screen-printed films so that the penetration of the electrical field can be ignored, leading to the low field enhancement factor [20].…”

X-ray generation using carbon nanotubes

“…It is a macro-scale process and affords very little reproducibility, Moreover; the necessary surfactants are usually vacuum unstable giving rise to emission profiles that deleteriously drift with time [170,[174][175][176]. CNT inks can often have significant out-gassing [177] when even modestly heated, compromising the vacuum envelope. The resultant reduction in field emission performance and reduced current density has, as a result, prevented CNT-based pastes and ink from gaining commercial traction, though cathodes fabricated in this way appeal as the reduced reproducibility is off-set by the ease of fabrication.…”

“…Elsewhere it has been widely used as a means of depositing phosphor materials. It has also been applied to the deposition of bundles of SWCNTs on various substrates, such as stainless steel or doped Si [167][168][169][170][171][172][173][174][175][176][177][178][179]. Composite CNT films deposited by electrophoresis have been fabricated with controlled surface density with good field emission performance, current density and long-term stability under high operating voltages, which has been applied to an electron source for high-resolution X-ray imaging [160].…”