Emission characteristics of printed carbon nanotube cathodes after laser treatment

Abstract

Relationship between field-emission characteristics and defects measured by Raman scattering in carbonnanotube cathodes treated by plasma and laser Improvement of emission characteristics uniformity of carbon nanotube field emission display by surface treatment J.Recently, field emission displays using printed carbon nanotubes ͑CNTs͒ as an emitter have been researched eagerly. By laser irradiation, some CNTs in the printed CNT layer stand out, and they work as the emission sites. We found that the higher CNTs that are easier to be the emission sites tend to exist at the boundary of the laser irradiation pattern. We used the irradiation patterns that consist of the arrays of microirradiation pattern to increase the total length of boundary. Both emission characteristics and emission uniformity were improved by the increase of the boundary length. We examined several lasers, and the irradiation by the second harmonic generation yttrium aluminum garnet laser of which wavelength was greatest in our experiment provided the best emission characteristics ͑turn-on electric field Ͻ2 V/m͒ and emission uniformity ͑turn-on electric field deviation Ͻ5%͒.

Enhanced field emission characteristics of zinc oxide mixed carbon nano-tubes films

“…To improve adhesion and emission uniformity of cathode film, CNT paste was synthesized using different inorganic and organic vehicles [7,8]. In addition, laser treatment [9][10][11], plasma treatment [12], mechanical rubbing [13][14][15] and adhesive tapping [16] have been applied to increase effective CNT emitters. Moreover, processing temperature and time [17,18] as effective parameter are also studied to activate more emission sites.…”

Field Emission from Conducting Polymer/Single-Walled Carbon Nanotube Composite Prepared by AC Coupled Electrophoresis

“…Field-emission displays (FEDs) have been attracting a great deal of attention recently as one of the most promising flat-panel displays owing to their high display quality and low power consumption since the field emission characteristics of carbon nanotubes (CNTs) were first reported in 1995. [1][2][3][4] Many fabrication techniques of CNT arrays have been reported, such as chemical vapor deposition (CVD), [1][2][3][4][5][6][7][8] screen-printing method, [9][10][11][12] electrophoresis [13][14][15] as well as patterning and alignment processes. Among them, wellaligned CNT emitters fabricated by CVD are currently expected to be used as field emitters because of their low turn-on/threshold voltage and excellent current density.…”

“…16) Printing techniques such as screen printing and electrophoresis have an advantage in terms of low-cost and largearea processing. [9][10][11][12][13][14][15] However, several surface treatments to make CNT tips protrude from the cathode surface have been required for the improvement of emission properties and uniformity, such as mechanical surface, plasma, and laser treatments. [9][10][11][12] Therefore, a technique for the alignment of CNTs during the deposition process seems to be one of the key issues for the fabrication of low-cost, large-area cathodes.…”

Enhanced Field Emission of Single-Wall Carbon Nanotube Cathode Prepared by Screen Printing with a Silver Paste Buffer Layer

“…Paste mixing of CNTs in the printed cathode layer showed very poor electron emission characteristics because of their insufficient outcrop to the surface, random distribution, and possible organic residues. In order to remove these residues, tape pasting [ 22 ], mechanical friction [ 23 ], and laser irradiation [ 24 ] are generally used. Tape sticking and mechanical friction methods mainly remove the organic matter through the action of mechanical force.…”