Enhanced electron field emission characteristics of single-walled carbon nanotube films by ultrasonic bonding

• A novel ultrasonic bonding process was used to fabricate the electron field emission.
• The mechanical and electrical contact between SWCNTs and metal layer was impoved.
• Electron field emission properties were improved remarkably.
• Turn-on voltage of bonded SWCNTs film showed significant decrease.
• The emission current of bonded SWCNTs film was much stabilized.

A novel ultrasonic bonding process was used to fabricate the electron field emission cathode of single-walled nanotube film, which was deposited on an Al plate substrate by electrophoretic deposition. Electron field emission properties were improved remarkably after the cathode carbon nanotubes nanobonded with the Al substrate. Turn-on voltage showed a significant decrease and the emission current was much stabilized. This can be attributed to the reduction of the contact resistance in bonding area and easily moving electrons for field emission after ultrasonic bonding. In addition, the field emission performances of SWCNTs films formed at different bonding conditions were also studied. With a simple nano-bonding apparatus, this technique has low cost, and can be utilized for extensively roboticized fabrication of high performance field emission cathodes with short process time.