THIN-FILMS OF CUBIC BORON-NITRIDE ON SILICON

Thin films of cubic boron nitride were grown on Si(100) surfaces using an ion-beam-assisted physical vapour deposition process. We studied the film microstructure with transmission electron microscopy and selected-area electron diffraction. The films are polycrystalline with a grain size as large as 0.4 mu m. Sometimes individual grains are found to extend through the film. Electron diffraction and large-angle tilting were used to identify clearly the structure as cubic boron nitride. Multiple twins on (111) planes are abundant in individual grains, as revealed by electron diffraction.