Thickness and microstructure influence on the nanocrystalline Cu thin films’ mechanical properties

ROA, SIMÓN; SIRENA, MARTÍN

JOURNAL OF MATERIALS RESEARCH

MATERIALS RESEARCH SOC

Año: 2021 vol. 36 p. 938 - 948

0884-2914

We report a systematic study about the thickness and microstructure influence on the mechanical properties of nanocrystalline Cu thin films grown by DC sputtering. Mechanical properties were determined by using atomic force microscopy-assisted nanoindentation. Results showed a clear decrease of the elastic modulus and indentation hardness as the film thickness and grain size increase. Annealing time as well as the temperature seem to affect the mechanical behavior of the films by inducing microstructural changes, producing comparable changes to those produced by size effects (film thickness). Results suggest that both effects are important to explain the mechanical behavior of polycrystalline thin films. This work helps understanding what physical mechanisms play a fundamental role on the mechanical behavior of thin films. Graphic abstract: [Figure not available: see fulltext.].