DIELECTRIC AND RAMAN-SPECTROSCOPY OF MWCVD DIAMOND THIN-FILMS

The dielectric properties of diamond thin films obtained on silicon su bstrates by microwave plasma-assisted chemical vapour deposition (MWCV D) have been measured in the frequency range from 0.1 to 10(3) kHz at different temperatures up to 150 degrees C. The experimental results h ave been discussed in terms of the many body theory for dielectric rel axation in solids. Dielectric parameters as well as the d.c. conductiv ity of the samples have been correlated with the morphology and diamon d content in the films, respectively detected from scanning electron m icroscopy (SEM) and Raman spectroscopy. The calculated activation ener gies for the dielectric relaxation mechanism agree with those obtained from other measurement techniques used in the electrical characteriza tion of diamond films.