Amorphous carbon deposited by pulsed laser ablation as material for cold cathode flat emitters

Pulsed laser deposition of carbon-based materials has been explored in order to obtain cold cathode flat emitters with high emission current density and low threshold field, and to examine the factors controlling the electron field emission behaviour. In this paper, results on amorphous carbon thin films deposited on silicon by pulsed laser ablation (PLA) from a graphite target, using a KrF excimer laser are presented. The structure and surface morphology of carbon materials have been examined by transmission electron microscopy (TEM) and Raman spectroscopy. I–V characteristics of the carbon films have been measured by a diode technique (below 10-4Pa). Some effects of the deposition parameters on thin film uniformity, adhesion, and field emission performances have been investigated. Emission current density as high as 50mA/cm2 at an electric field of 70V/µm has been obtained on 100nm thick, smooth and glassy carbon films deposited at 150°C.