Improved field emission stability and uniformity of printed carbon nanotubes prepared using high energy-milled glass frit

• Examine the effects of glass frit properties on the field emission properties and stability.
• Synthesis of MWCNTs having straight morphology by chemical vapor deposition.
• Finer and more uniformly distributed glass frits by 3 h of high energy milling.
• Uniform emission and enhanced long-term stability with the high energy-milled frits.

Stable and uniform electron field emitters were fabricated by the screen-printing of a carbon nanotube (CNT) paste. The CNT paste was prepared by mixing thin multi-walled CNTs, organic binder and glass frits in terpineol followed by three-roll milling. The paste was screen-printed onto an indium tin oxide (ITO)-coated glass substrate and exposed to firing. The emitters formed by the adhesive tape treatment of the printed pastes generally showed non-uniform heights of emitting tips due to the large-sized glass frit distributed in the paste. On the other hand, small glass frits with a uniform particle size distribution could be obtained by high energy milling. In addition, the CNT paste prepared using the high energy-milled glass frits showed very uniform tip heights. The uniform CNT tip height was found to play an important role in acquiring the long-term emission stability and uniformity of field emitters.