Effect of low negative bias on electrical properties of nitrogen doped amorphous carbon thin films using bias-assisted pyrolysis-CVD

Amorphous carbon thin films were deposited on glass substrates by using low negative bias voltage in the range of -10V to -50V at 500°C in 1 hour deposition. The effect of low negative bias voltage on electrical properties of nitrogen doped amorphous carbon thin films were determined. The amorphous carbon thin films were characterized by current-voltage measurement, and atomic force microscopy. Various responds of ohmic contacts were found from all samples due to different resistance value. The resistivity values of a-C thin films from 0V to -50V were 4.974×10⁷ Ωcm, 1.569×10³ Ωcm, 3.21×10² Ωcm, 0.11×10² Ωcm, and 1.845×10⁴ Ωcm respectively. It has seen that, doping with nitrogen in low negative bias voltage can modify the electrical properties where conductivity and photo response were increased compared without nitrogen doped and the optimum bias is found at -40V.