Abstract

Hydrogenated amorphous carbon (a-C:H) films have been prepared in a r.f. deposition reactor on negatively self-biased substrates from pure CH4 gas at a relatively low pressure (2.5 Pa) and over a wide range of substrate bias voltages V(SB) (200-1200 V). Changes in film properties due to bias have been systematically investigated by scanning electron microscopy, transmission electron microscopy, Fourier transform IR spectroscopy ellipsometry and microhardness. The experimental results revealed that a-C:H properties are highly dependent on V(SB).