Structure and deformation behavior of Zr-Cu thin films deposited on Kapton substrates

In the present work we study Zr-Cu thin films deposited on flexible Kapton substrates by magnetron sputtering. The morphology of “as-grown” films had complex hierarchical structure with size of building blocks from ~ 14 nm to ~ 3 μm. The larger was the size of hierarchical unit, the thicker was the boundary separating it from adjacent units of similar size. During the bending tests cracks propagated predominantly between the largest blocks, indicating the negative impact of the wide interfaces on the mechanical properties of thin films. Crystallization shrinkage and thermal contraction were described as factors that contribute to the development of the boundaries.