Structural and Electronic Characterization of Nanocrystalline Diamondlike Carbon Thin Films

The origin of low threshold field-emission (threshold field 1.25 V/μm) in nanocrystalline diamond-like carbon (nc-DLC) thin films is examined. The introduction of nitrogen and thermal annealing are both observed to change the threshold field and these changes are correlated with changes to the film microstructure. A range of different techniques including micro-Raman and infrared spectroscopy, X-ray diffraction, electron microscopy, energy-dispersive X-ray analysis and time-of-flight-secondary ion mass spectroscopy are used to examine the properties of the films. A comparison of the field emission properties of nc-DLC films with atomically smooth amorphous DLC (a-DLC) films reveals that nc-DLC films have lower threshold fields. Our results show that nc-DLC can be a good candidate for large area field emission display panels and cold cathode emission devices.