LASER-ASSISTED CHEMICAL-VAPOR-DEPOSITION OF GRAPHITE

Photolysis of naphthalene-1,4,5,8-tetracarboxylic acid dianhydride vap or using a beam from a KrF (248 nm) excimer laser focused onto a silic on substrate gives a carbon film. Analysis of the film by Auger electr on spectroscopy gave three peaks at 268, 255, and 241 eV which confirm s the graphitic nature of the carbon deposit. Raman spectroscopy in th e reflectance mode gives a narrow band at 1577 cm-1, similar to single crystal or highly ordered pyrolytic graphite; however, this band is a ccompanied by a weaker band at 1350 cm-1 which indicates there is some disorder in the graphitic structure. The use of the laser-assisted pr ocess allows the deposition of high-purity graphite films without heat ing the substrate, whereas the conventional thermal process requires d eposition temperatures of 800-degrees-C and annealing at 2000-degrees- C to obtain a similar quality film.