Field emission properties of diamond-like carbon films annealed at different temperatures

Effect of annealing on the field emission properties of diamond-like carbon (DLC) films deposited by high power excime laser technique was studied. Raman spectrometry and X-ray photoelectron spectrometry (XPS) were used to determine the chemical bonding structural change of the annealed DLC films. It was found that the annealing transformed gradually DLC films into a graphitic structure as annealing temperature was increased to more than 600 8C, simultaneously field emission properties of DLC films were enhanced markedly. Graphitization of DLC films induced by annealing caused the formation of a large fraction of sp2 C in the DLC films, which played an important role in the enhancement of field emission properties for DLC films. Rich sp2 C cluster acted as a conduction part in the films could increase the conductivity of DLC films and lower the effective work function of DLC films, consequently improve field emission properties of DLC films.