Abstract
The bonding structure of cubic boron nitride films with different levels of intrinsic stress has been studied from the -shell x-ray absorption near-edge structure (XANES). The stress level was tuned by the damage induced from simultaneous medium-energy ion implantation during growth. The films show a dominant arrangement for damage values below a certain threshold, with an appreciable to transformation taking place above this limit. Interestingly, the degree of stress in structures is reflected in the spectral line shape, which progressively converges to that of stress-free powder for increasing ion damage. These results indicate that stress buildup and release occur at a microscopic level. The changes in the spectral line shape are correlated with modifications in the electronic structure due to the presence of intrinsic stress and bond distortion within the cubic network, as predicted by density functional theory calculations. Our findings reveal the potential of XANES spectroscopy to detect stress in disordered BN systems.
- Received 30 July 2007
DOI:https://doi.org/10.1103/PhysRevB.76.174111
©2007 American Physical Society