Improvement of Adhesion of Cubic Boron Nitride Films: Effect of Interlayer and Deposition Parameters

Diamond and B4C coatings were used as an interlayer for the growth of cubic boron nitride thin films on c-silicon. By employing a B-C-N gradient layer on top of the B4C interlayer, improved adhesion occured between BN and B4C. A multi-step process after the nucleation of c-BN was found very helpful for improving the adhesion of c-BN on silicon with interlayers. Residual stress of c-BN thin film was significantly decreased by using a new post-deposition annealing treatment.