Stability of field emission current for tetrahedral amorphous carbon films prepared by filtered vacuum arc deposition

We have studied the field emission characteristics and the stabilities of tetrahedral amorphous carbon (ta-C) films deposited by FAD (filtered cathodic vacuum arc deposition method) on the p⁺-Si at the bias of 200 V. The emission current of conventional ta-C increases at first and then decreases with increasing stress time. On the other hand, the multi-layered ta-C showed less degradation in emission current during bias-stress. The fluctuation of emission current decreased after bias-stress for long time. The resistivity of the ta-C increases after bias-stress for long time due to the change in the density of states in the gap of the ta-C.