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Titanium-containing tetrahedral amorphous carbon (ta-C:Ti) films with different titanium content were deposited by a filtered cathodic vacuum arc technique. The microstructure of these films was confirmed to be of ta-C+TiCx(x<1) nanocomposite by Rutherford backscattering spectroscopy, x-ray diffraction, and micro-Raman spectroscopy experiments. With the increase of titanium content, the titanium carbide content increased and the sp3 fraction in the residual ta-C phase decreased gradually. In the electron field emission tests, it was found that proper conditioning processes are necessary for all these films in order to get a steady reproducible emission behavior. After conditioning, the emission threshold field of the films is about the same value, around 10 V/μm, except for the film with the lowest titanium content (∼1.2 at%) of which the threshold field is much higher, around 17–18 V/μm. The optimum titanium concentration in the film for field emission, showing the highest emission current and emission site density, is about 12 at%. After field emission testing, graphitization was involved and the titanium carbide phase, at least some of the sub-stoichiometric TiCx phase, in the ta-C:Ti films decomposed.

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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.