Effect of the substrate bias on the Raman spectra and thermal stability of diamond-like carbon (DLC) and silicon-modified DLC films prepared by plasma-enhanced chemical vapour deposition (PECVD)

An investigation of the dependence of the thermal stability of DLC (a-C:H) and silicon-modified DLC (a-C:H:Si) films on film-deposition conditions has been conducted. An interpretation based on plasma chemistry, x-ray photoelectron spectroscopy, confocal Raman spectroscopy and substrate-bias-voltage changes is proposed to explain the thermally induced structural modifications in the films between 200 and 600 °C. Our recent finding is expected to be beneficial to those designing thermal annealing schedules for reducing or eliminating residual stresses in the films.