Effect of Gas Flow Rate on the Properties of Amorphous Carbon Thin Films Prepared by Thermal CVD Using Camphoric Carbon Precursor

Abstract

Amorphous carbon (a-C) thin films have been prepared by a simple thermal CVD using camphor oil as precursor. The effects of argon gas flow rate on electrical, optical and structural properties of a-C thin films have been investigated. The a-C thin films were characterized by using current-voltage (I-V) measurement, UV-Vis-NIR spectroscopy, Raman and FTIR spectroscopy. The I-V study reveals that the electrical conductivity was increased with increasing argon gas flow rate. It was found that the optical band gap decreased from 0.88 to 0.42 eV as gas flow rate increased which indicates a microstructural disorder at different gas flow rate. Raman and FTIR studies reveal the amorphous structures which consist of a mixture of sp2 and sp3 bonded carbon atoms.