Fabrication of DLC nanoparticle clusters by μ-wave oven based plasma reactor with acetylene diluted in air precursor

Abstract

This work developed a microwave oven based plasma reactor operated under vacuum pressure. This microwave plasma deposition system used to deposit diamond-like carbon (DLC) thin film on silicon substrate. System is custom-made and economically provides a very inexpensive way to conduct film deposition experiments by using a household microwave oven as a microwave source to get plasma discharge. DLC thin films were successfully deposited on silicon substrates by pure acetylene (C2H2) plasma. Plasma species composed of; CN, N2, CO, C2, and H are presented revealed by Optical Emission Spectroscopy. Energy Dispersive X-ray analysis indicated that the deposited film composed of carbon atoms 46.25% and silicon atoms 53.75%. Raman analysis showed D-band, G-band and nanocrystalline diamond band with sp3-hybridization contained in the films in the range of 48.75–64.08% that composed of chemical bonding; CC, CO, CN, CN, CO, CNH, NO, OH and HOH, analyzed by XPS technique. XRD indicated that the grown films are cubic diamond (1 1 1) crystallography and formed in coral-like clusters from nanoparticles of a mixture between sp2 and sp3 hybridization with high porosity in surface texture that introducing the hydrophobic property on the grown DLC surface by changing the hydrophilic property of smooth silicon substrate surface.