Electron field emission from diamond-like carbon nanodot arrays

Diamond-like carbon (DLC) nanodot arrays were prepared by filtered cathodic arc plasma (FCAP) technique at room temperature with the aid of anodic aluminum oxide (AAO) template at a bias of −50 V. The average diameter of highly ordered and vertical DLC nanodots was ∼90 nm, and the nanodot density was estimated to be ∼1010 cm−2. A broad asymmetric band attributed to characteristic band of DLC ranging from 1000 to 2000 cm−1 was detected by Raman spectrum. A sp3/(sp3+sp2) ratio of 68.2% was measured by X-ray photoelectron spectrum (XPS). A low threshold field of 4 V/μm at 10 mA/cm2 and a high current density of 43.2 mA/cm2 at 5 V/μm were achieved. And based on Fowler–Nordheim plot, the value of work function for the DLC nanodot arrays was estimated in the range 0.4–1.84 from a linear plot. The results show that the DLC nanodot arrays can be a promising candidate as a field emission emitter.