Mass spectrometric investigations on CH4 plasmas obtained from a dual electron cyclotron resonance-radio frequency discharge

Diamond-like carbon (DLC) thin films have been prepared by chemical vapour deposition assisted by electron cyclotron resonance (ECR) plasma of methane at low pressure. with radio frequency (RF) power applied to the substrate. This paper is focused on the plasma diagnostic investigations by mass spectrometry in terms of neutral and ionic populations. ion energy distribution of different species is also presented and the influence of ECR and/or RF excitations on the energy of ion bombardment is studied. The role of different ionic or neutral species in the growth mechanism and in the formation of nanocrystalline clusters in an amorphous matrix, as observed in a previous study by transmission electron microscopy and electron energy loss spectroscopy, is discussed here.