Free-standing diamond films grown on cobalt substrates

Diamond films were grown directly on cobalt substrates, using microwave pla sma-assisted chemical vapour deposition. Although cobalt is known to inhibi t the nucleation of diamond and enhancing, the formation of graphite, we we re able to grow relatively thick films (similar to 190 mum) The films were easily detached from the subcstrates. The poor adhesion allows the possibil ity of obtaining free-standing diamond films without chemical etching. Micr o-Raman spectroscopy showed the 1332 cm(-1) characteristic Raman peak of di amond and the 1580 cm(-1), 1360 cm(-1) bands of graphite, on the growth sur face and backside of the films, respectively. Through scanning electron mic roscopy and X-ray diffraction we were able to monitor film thickness and mo rphology with growth evolution. The results showed the (111) preferential g rowth morphology for the film with higher growth rate. By energy dispersive X-ray spectroscopy it was only possible to detect cobalt in the back of th e films, but not in the surface. The role of cobalt in the film growth is d iscussed. (C) 2001 Elsevier Science B.V. All rights reserved.