In-situ Stress Diagnostics

Stress is a common property of thin films. After a brief summary of origins and effects of stresses in thin films the particular situation in amorphous and nano-crystalline films is discussed. The problems related to the extremely high compressive stresses in cubic boron nitride (cBN) have been tackled either by the deposition of buffer layers or by attempts to reduce the stress in the film. These approaches are compared and discussed. Intrinsic stress depth profiles in BN films, as well as the influence of post-deposition thermal treatment and ion irradiation on the global stress, as obtained from in-situ cantilever bending measurements, are reviewed. A technique for the growth of cBN films with significantly reduced compressive stress is demonstrated.