Enhancement of Field Emission Properties in Ultra-Nano-Crystalline Diamond Films Upon 100 Kev Nickel Ion Implantation

The effects of 100 keV nickel (Ni) ion implantation on modifying the surface morphology and the electron field emission (EFE) properties of two types (ultra-nano-crystalline diamond) UNCD films (with or without the addition of nitrogen gas during their deposition process) were studied. The Ni ion implantation provides a moderate improvement in both electrical and EFE properties of two types of UNCD films. However, for the UNCD film of nitrogen(N) in the growth process after Ni ion implantation, the results in the surface resistivity of the UNCD film is as low as 87.6 Ω/sq, and the corresponding mobility reach to 48.5 cm 2 V -1 s -1 . The excellent EFE property can be attained when turn on field at E 0 =2.85 V/μm, and a current density of 200.16 μA/cm 2 can be obtained under an applied electric field of 4.53 V/μm. Formation of network structure on film surface shows the importance in forming the electron transport path on improving the EFE properties of UNCD film. The results of Raman spectroscopy confirmed that a multitude of nano-graphite phases were formed inside the UNCD film during Ni ion implantation, which provide an effective channel for the transportation and release of electrons. Presumably, the formation of network structures and the generation of nano-graphite phase enhance the EFE performance of the UNCD film by enhancing the electron transport channel and electron release ability