The elastic constants c11 and c44 of single-crystal NaCl-structure δ-TiNx (001) layers, with x ranging from 0.67 to 1.0, were determined using sound velocity measurements. Picosecond ultrasonic optical pump/probe techniques were employed to generate and detect longitudinal sound waves and surface acoustic waves (SAW) in order to obtain c11 (x) and c44 (x), respectively. SAW generation was achieved by depositing a periodic series of Al bars on the Ti Nx (001) layers to spatially modulate the surface reflectivity. c11 and c44 were found to decrease continuously from 626 and 156 GPa with x=1 to 439 and 92 GPa with x=0.67. The Voit-Reuss-Hill average aggregate elastic moduli EVRH (x) obtained from our measured c11 (x) and c44 (x) values are in good agreement with previous Ti Nx (001) nanoindentation results.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2005 Dec 15|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics