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A polymer, poly͑phenylcarbyne͒ ͑PPC͒, was converted to carbon film by ultraviolet pulsed-laser ͑KrF, ϭ248 nm͒ irradiation in nitrogen atmosphere at room temperature. The irradiated PPC consisted of fine graphitic carbon particles of several tens of nm in size, and exhibited good field emission properties. Low turn-on emission field of 2 V/m ͑at 1 nA/cm 2 ͒, high emission current density of 20 mA/cm 2 ͑at 12 V/m͒, and high emission luminescent spots density of 10 4 /cm 2 were observed for the polymer film irradiated by a pulsed-laser fluence of 40 mJ/cm 2 . We demonstrate multiple-lines and 2ϫ5 array field emission patterns using the laser irradiation of PPC.

Ta-C and iron containing amorphous carbon (a-C:Fe) films were deposited by filtered cathodic vacuum arc technique. The influences of Fe contents on the wettability of the films were investigated in terms of surface energy. The surface energy of a-C:Fe films was determined by the contact angle measurement. Atomic force microscopy (AFM), Raman spectroscopy and X-ray induced photoelectron spectroscopy (XPS) were employed to analyze the origin of the variation of surface energy with various Fe content. It is found that the contact angle for water increases significantly after incorporating Fe into the films and the films become hydrophobic. The roughness of these films has a little effect on the contact angle. The surface energy is reduced after incorporating Fe into the a-C film which is due to the reduction of both dispersive and polar component. The reduction in dispersive component is ascribed to the decrease of atomic density of the a-C:Fe films due to the increase in sp2 bonded carbon. The absorption of oxygen on the surface play an important role in the reduction of polar component for the a-C:Fe films. It is proposed that such network as (Ca-O-Fe)-O-(Fe-O-Ca) may be formed and responsible for the reduction of polar component.

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