Structural and electrical properties of nitrogen-doped Cr-C:H films synthesized by a cathodic-arc activated deposition process

Nitrogen-doped Cr-C:H/N films were synthesized by using a cathodic-arc activated deposition process. Chromium plasma with intensive ion energies catalyzes the decomposition of hydrocarbon gas (C2H2), and results in the deposition of amorphous carbon films. Nitrogen was introduced to form nitrogen-containing Cr-C:H/N films, which contained a mixture of sp2 and sp3 carbon bonds. The deposited carbon films consist of nanocomposite Cr-C:H/N films on top of a graded chromium nitride interlayer. It has been found that the structural and electrical properties of the films were correlated as a function of nitrogen doping. The nature of the heterojunction is confirmed by the spreading resistance characteristics of the Cr-C:H/N film/Si junction showing a behavior dependant on the nitrogen doping induced structure changes. With increasing nitrogen concentration, the increasing π states of sp2 hybridization results in a more pronounced enhancement of conductivity.