Electrical and electronic properties of nitrogen doped amorphous carbon (a-CNx) thin films

Nitrogen-doped amorphous carbon thin films (a-CNx) were prepared on silicon substrate by pulsed laser deposition process using methane (CH4) and nitrogen (N2) as source gas. The electrical properties of a-CNx films changes with nitrogen concentration in the film structure. The intensity ratio of the D and G peak (ID/IG) increases with higher nitrogen concentration, which means that sp2-clusters were formed in these films and is responsible for the enhancement of conductivity of the a-CNx films. We observed that the amorphous carbon (a-C) films becoming more graphitic in nature yielding higher conductivity/lower resistivity with increase of nitrogen concentration. Electron field emission result shows that the emission current density enhances with nitrogen doping that indicates the useful in electron field emission devices application.