The orientation between cubic boron nitride (cBN) crystallites and the tBN layers on which they grow was studied using high-resolution transmission electron microscopy. BN films were prepared by radio-frequency magnetron sputtering under conditions leading to the formation of ∼100% cBN films grown on a preceding tBN layer. Two types of orientations were observed: (i) cBN layers grown on the edges of the tBN(0002) planes so that the cBN111 planes are parallel to the tBN(0002) planes (as reported previously by many authors), (ii) cBN layers grown on curved tBN(0002) planes with no orientation to the tBN planes. The first type of cBN growth is associated with stress leading to delamination of cBN films thicker than 100 nm. The second type is associated with reduced stress enabling the growth of much thicker (∼500 nm) films at a relatively low (450°C) substrate deposition temperature. These results may be helpful in the fabrication of thick cBN films and improving our understanding of the cBN nucleation process.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)