Electron field emission from diamond-like carbon films and a patterned array by using a Ti interfacial layer

Abstract

Electron field emission from diamond-like carbon (DLC) films deposited on Si, Ti/Si, and Au/Si substrates by a filtered arc deposition technique was studied. As compared to DLC/Si and DLC/Au/Si, electron field emission from DLC/Ti/Si was enhanced, showing an increased emission current density and emission site density (∼1.2×103/cm2). An emission site density up to 2.2∼2.2×103/cm2 was obtained after the DLC/Ti/Si had been annealed at 430 °C for 0.5 h. A patterned DLC/Ti/Si array fabricated by the oxygen reactive ion beam etching technique showed further field emission enhancement. An emission site density up to 3.2∼3.5×103/cm2 and a threshold field as low as 2.1 V/μm were achieved. It was shown that the low potential barrier at the interface and high local geometric electric field enhancement around the edges produced by reactive ion beam etching were possible causes of the enhancing effects. It could also be explained by Geis’ metal-diamond-vacuum triple junction emission mechanism.