title: Coating of diamond-like carbon nanofilm on alumina by microwave plasma enhanced chemical vapor deposition process.
abstract: Diamond-like carbon (DLC) nanofilms with thickness varied from under one hundred to a few hundred nanometers have been successfully deposited on alumina substrates by microwave plasma enhanced chemical vapor deposition (MW-PECVD) process. To obtain dense continuous DLC nanofilm coating over the entire sample surface, alumina substrates were pre-treated to enhance the nucleation density. Raman spectra of DLC films on samples showed distinct diamond peak at around 1332 cm(-1), and the broad band of amorphous carbon phase at around 1550 cm(-1). Full width at half maximum height (FWHM) values indicated good formation of diamond phase in all films. The result of nano-indentation test show that the hardness of alumina samples increase from 7.3 +/- 2.0 GPa in uncoated samples to 15.8 +/- 4.5-52.2 +/- 2.1 GPa in samples coated with DLC depending on the process conditions. It is observed that the hardness values are still in good range although the thickness of the films is less than a hundred nanometer.
authors.affiliation: Center of Excellence in Particle Technology, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Chotiwan
authors.initials: C
authors.lastname: Rattanasatien
authors.forename: Nattaporn
authors.initials: N
authors.lastname: Tonanon
authors.forename: Worawan
authors.initials: W
authors.lastname: Bhanthumnavin
authors.forename: Boonchoat
authors.initials: B
authors.lastname: Paosawatyanyong
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D018130:Diamond / Q000737:chemistry; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008567:Membranes, Artificial; D008872:Microwaves; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D058626:Plasma Gases / Q000737:chemistry; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances; D008567:Membranes, Artificial; D058626:Plasma Gases; D002244:Carbon; D018130:Diamond; D000537:Aluminum Oxide