IN-SITU RAMAN INVESTIGATION OF DIAMOND FILMS DURING GROWTH AND ETCHING PROCESSES

Diamond films were prepared in a microwave plasma-assisted chemical vapour deposition (CVD) reactor. The deposition parameters were deliberately optimized to obtain mixtures of diamond and different carbonaceous compounds. We present the results of an in-situ Raman study of the growth of such films and of their etching under different atmospheres. At least six Raman bands in the range 1100-1600 cm-1 were observed; their relative intensity variation with the elaboration parameters, with the excitation wavelength and with the etching conditions led to the conclusion that at least three different carbonaceous forms are present in CVD diamond films. During the growth process, one first obtains the diamond phase along with a diamond-like compound; the disordered graphitic form appears only in a second stage.