DIAMOND DEPOSITION ON POLYCRYSTALLINE FILMS OF CUBIC BORON-NITRIDE

We have grown diamond films on films of cubic boron nitride (cBN). The cBN films were grown on Si(100) substrates using ion-assisted pulsed laser deposition. Fourier transform infrared (FTIR) spectroscopy indic ated that the BN films contained approximately 75% sp3-bonded cBN. The as-grown cBN films were inserted with no surface pretreatment (e.g., abrading or scratching) into a conventional hot filament diamond react or. In situ Raman spectroscopy was used to confirm diamond synthesis d uring growth. The nucleation density of the diamond films was estimate d at 1 X 10(9)/CM2, equivalent to or higher than the best values for s cratched silicon substrates. In addition, we found that the cBN films were etched in the diamond reactor; a film thickness greater than or s imilar to 1500 angstrom was required to prevent total film loss before diamond nucleation occurred. The presence of cBN under the diamond wa s established using FTIR spectroscopy 'and Auger electron spectroscopy .