Influence of Cr-N interlayer properties on the initial stages of CVD diamond growth on steel substrates

In our previous works, Cr-N interlayers have been reported to be a successful solution for the deposition of good adhered diamond films on steel substrates, The properties of the Cr-N interlayer have been found to have a strong effect on the initial stages of CVD diamond formation. In the present work, the effect of different nitridation temperatures on the initial stages of CVD diamond growth are reported. Surface morphology, incubation time and diamond particle density at the initial stages of deposition were studied by High Resolution Field Emission Gun Scanning Electron Microscopy (HR FEG SEM). Raman Spectroscopy was used to determined the quality of the deposited films, the presence of sp(2)-bonded carbon and residual stress in the diamond films. Phase composition and element profiles across the interlayer were investigated after different pretreatments and as a function of deposition time using X-ray Diffraction (XRD) and quantitative Electron Probe Microbeam Analysis (EPMA). Adhesion of the deposited diamond films to substrates nitrided at different temperatures was evaluated by the indentation technique, and was correlated with substrate surface morphology. (C) 1998 Elsevier Science S.A.