Shear strength measurements of hafnium diboride thin solid films

• Instrumented scratch method was employed to measure adhesion strength of the films.
• Hardness, modulus, and surface roughness were measured with deposition conditions.
• Shear strength values for as-deposited films were 1.1 GPa and 4.5 GPa.
• Shear strength values for annealed films were 3.5 GPa and 3.7 GPa.

Micromechanical and microscratch properties of chemical vapor deposition synthesized hafnium diboride thin solid films were measured. A range of synthesis conditions was explored by varying the substrate temperature, precursor pressure, and ex situ annealing conditions. Adhesion and shear strength measurements were performed using indentation and scratch techniques, respectively. The hardness of the as-deposited and annealed films was found to be in the 7–22 GPa and 6–32 GPa range, respectively. Scratch studies revealed a coefficient of friction of 0.13–0.21 depending on the deposition and annealing conditions with the as-deposited films exhibiting lower coefficient of friction. The adhesion strength was found to increase twofold to threefold with annealing, while annealing has no impact on the shear strength of the films.