Field emission from nitrogen doped tetrahedral amorphous carbon prepared by filtered cathodic vacuum arc technique

A study of field emission from nitrogen doped tetrahedral amorphous carbon (ta-C:N) films prepared by the filtered cathodic vacuum arc (FCVA) deposition technique is reported. Field emission from ta-C:N films deposited on Si substrates was investigated in a diode configuration at room temperature and base pressure of 2.0 × 10^-6 Torr. The J-E curves shift significantly towards the low potential side with increasing nitrogen concentration. The lowest field at which field emission was obtained was 10 V μm^-1. A current density of 0.1 mA mm^-2 (assuming the entire film surface is emitting) at 50 V μm^-1 was obtained from these films. Electronic parameters, i.e., the band gap energy and activation energy were measured in order to construct an energy band diagram for the heterojunction structure, and the field emission mechanism is proposed based on this structure.