The structure and field emission enhancement properties of nano-structured flower-like graphitic films

Nano-crystalline graphite films were grown on ceramic substrates by microwave plasma chemical vapor deposition system using Fe–Ni–Cr layer as catalyst deposited by magnetron sputtering method. The microstructure and surface morphology of the nano-crystalline graphite were characterized by X-ray diffraction, Raman spectrum, Scanning electron microscope, and Transmission electron microscope. The measurement results revealed that nano-crystalline graphite film consisted of a series flower-like carbon clusters, which contains a few nano-crystalline graphitic slices. The thickness of the slice is less than 10 nm. The nano-crystalline graphitic film exhibited good field emission properties, which has the turn-on field of 1.26 V/µm, and the current density of 2.1 mA/cm2 at electric field of 2.2 V/µm. The emission mechanism of nano-crystalline graphitic film was also studied.