Bh. Lung et al., Growth characterization and properties of diamond-like carbon films by electron cyclotron resonance chemical vapor deposition, THIN SOL FI, 392(1), 2001, pp. 16-21
Diamond-like carbon (DLC) films were deposited on radio-frequency (RF) bias
ed substrates at low temperature by electron cyclotron resonance microwave
plasma chemical vapor deposition using CH4-Ar as reactant gas. The effects
of gas composition ratio, microwave power and RF bias on growth rate, struc
ture and hardness of the films were investigated. Raman spectroscopy, Fouri
er transform infrared spectroscopy (FTIR) and Vickers microhardness tests w
ere used to determine the structural change and properties of the DLC films
. By changing the microwave power, the growth rate shows a maximum value of
1.6 mum/h at 150 W. From Raman spectra of the films deposited at different
microwave power and RF bias, the peaks centered at 1540 +/- 20 cm(-1) for
the deposited films, which was the characteristic peak of DLC coatings. By
increasing the RF bias the CI-I,, peaks in the FTIR spectra decreased becau
se of hydrogen evolution. The film hardness increased with the increase in
microwave power and RF bias. DLC films synthesized at a bias voltage of - (
100-250) V and CH4/Ar gas ratio of 2/7 exhibited extreme hardness of more t
han 3000 kg mm(-2). The role of adding Ar in reactant gases on DLC depositi
on was also discussed. (C) 2001 Elsevier Science B.V. All rights reserved.