The effects of nitrogen and annealing on the electrical property of the diamond-like carbon (DLC) films

The nitrogenated diamond-like carbon films (a-C:H:N) were deposited on Si-wafer by the rf-PECVD method with the addition of nitrogen to the mixture gas of methane and hydrogen. We were investigating the effect of the additive nitrogen gases and annealing in relationship between bonding structure and electrical properties of the deposited films. The electrical conductivity of films increased with the flow rate of nitrogen increasing up to 10 seem. Also as annealing temperature was increased, the electrical conductivity of films increased. The structure analysis results show that an increase of the flow rate of nitrogen and annealing temperature favor the formation of sp(2) bonding in the films. Therefore, we confirmed that the increase of the electrical conductivity is due to structure change by graphitization of the films.