Defects in CVD diamond: Raman and XRD studies

Our earlier studies on diamond films grown by the hot filament CVD (HFCVD,) technique have clearly shown the presence of the non-diamond phase in case of samples grown at higher deposition pressures. Results of more detailed investigations of samples grown at higher as well as lower deposition pressures by Raman and XRD techniques are reported in this paper. Appreciable broadening of the features in the Raman spectra of films grown at higher deposition pressures is attributed to the presence of the anisotropic stress in the samples. XRD studies have provided information regarding the domain size and the strain. The strain in the case of samples grown at higher deposition pressures is found to be five times higher than in samples grown at lower deposition pressures. The observed strain is correlated with the growth pressure. (C) 2002 Elsevier Science B.V. All rights reserved.