DIELECTRIC CHARACTERIZATION OF OXYACETYLENE FLAME-DEPOSITED DIAMOND THIN-FILMS

The dielectric properties of CVD diamond films grown by the oxyacetyle ne flame method for frequency dependent electrical fields have been st udied. The dependence of these properties on temperature (from room te mperature to 150 degrees C) has also been analysed. The DC conductivit y due to free carriers (sigma(0)) is obtained for each temperature usi ng the Kramers-Kronig transformations of the experimental data. The va lues of the conductivity are very low in all cases and close to those of natural diamond (10(-16)(Omega cm)(-1)); this is an indication of t he low graphite content of the samples. We have also calculated the di electric losses in the whole frequency range (100 mHz-1 MHz). A study of the relationship between the different deposition conditions with r espect to the dielectric properties has been carried out. The microstr ucture of the films has been characterised with SEM and Raman spectros copy. (C) 1997 Elsevier Science S.A.