Effect of N doping on properties of diamond-like carbon thin films produced by RF capacitively coupled chemical vapor deposition from different precursors

摘要

In this paper, we report results concerning properties of diamond-like carbon (DLC) thin films obtained in different experimental conditions: various RF power values and different precursors (methane, acetone and toluene or in combination with nitrogen). The deposition rate of DLC thin films obtained from precursors with low ionizing energy and high number of carbon atoms in molecule as acetone and toluene was higher (142 nm/min for acetone and 607 nm/min for toluene as compared with 79 nm/min for methane at 400 W input power). The highest value of hardness was obtained from methane (18 GPa). In the case of acetone and toluene precursors, the hardness increased with input power to the highest values of 16.8 and 14.8 GPa. By utilizing nitrogen as doping element, the resistivity of DLC thin films obtained from methane and acetone decreased from values higher than 10{sup}7Ωcm to lower values of 12.5 × 10{sup}3Ωcm for 3.79% nitrogen atomic concentration in the case of films obtained from methane and 40 × 10{sup}3 Ω cm for 4.26% nitrogen atomic concentration in the case of films obtained from acetone.