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We synthesize the diamond-like carbon(DLC) films using pulsed laser deposition(PLD) process. And then post-treat the films using plasma, which is induced by radio frequency(RF). We are going to examine the effect of the plasma-to-film interaction on the physical and electrical properties of the DLC films. The characteristics of plasma; which includes Ar, N_2 or O_2 species, will be systematically varied in order to further understand their influence on electronfield emission. It is known that pulsed laser deposited DLC films contain high sp^3/sp^2 ratio, which significantly influences the electron field emission properties of the DLC films. We expect that plasma-to-film interaction will markedly modify the sp^3/sp^2 ratio and thus pronouncedly alter the field emission properties of thefilms. We systematically examine modifications on the post-treated films using Raman spectroscopy and atomic force microscopy. We found that the argon plasma modifies the characteristics of the DLC films mainly through the ionic bombardment, resulting in significant damage on the DLC films. By contrast, thenitrogen and oxygen-plasma interact with the DLC films chemically such that thesp^3-to-sp^2 bond ratio is altered. The modification on the electron field emission of the DLC films is proportional to the density of the plasma. The DLC/Cr/Si films (0.4 um) deposited at 200℃ possess good emission current density (J_e)=45 uA/cm^2, with turn-on field (E_0)=7.2 V/um, and the emission properties increase to (J_e)_Ar=942 uA/cm^2, with turn-on field (E_0)_Ar=6.8 V/um, after plasma treatment.
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