Effects of nitrogen addition on the structure and field emission properties of amorphous carbon

The films of amorphous carbon with different amount of incorporated nitrogen are deposited by helical resonator plasma enhanced chemical vapor deposition using CH/sub 4/, Ar, and N/sub 2/ gas mixture. As the increase of nitrogen in the films, the optical band gap and sp/sup 3/ bond fraction decreased. The higher field emission current and the lower turn-on voltage are obtained from the sample of the higher nitrogen content. The increase of the conducting part of the films and the role of nitrogen as an electrical donor are responsible for the enhanced field emission.