On the hydrogen incorporation, intrinsic stress and thermal stability of hydrogenated amorphous carbon films deposited from an electron cyclotron resonance plasma

Diamond-like carbon films have been prepared by plasma enhanced chemical va pour deposition of methane at low pressure, in a dual ECR-RF glow discharge , at two different bias voltages -30 and -600 V and with different thicknes ses (0.2, 0.5 and 0.8 mum). The differences in the microstructure and the i ntrinsic stress of the films were investigated in relationship to the H con tent and bonding. Annealing of the samples in vacuum at temperature up to 6 00 degreesC produces changes in their structural properties and the intrins ic stress. These changes are found to be strongly dependent on the depositi on conditions. The stress results, correlated with infrared, thermal desorp tion mass spectroscopy and elastic recoil detection analysis data show that annealing at high temperature (450-550 degreesC) produces two different re laxation processes. A relaxation by atomic rearrangement and a reduction of the volumetric distortion in aromatic domains for the films deposited at - 30 V, and a relaxation by peeling for those grown at -600 V. (C) 2001 Elsev ier Science B.V. All rights reserved.