Abstract
Flexible electronic devices need to survive bending or stretching operation without mechanical failure. If inorganic thin films are involved in the device structure, the evolution of cracks is a major challenge to overcome. Here, we report a novel way to substantially improve the fracture behavior of films that are based on intentional utilization of residual stress on the films by in situ sputtering on a stretched polymer substrate. The in situ sputtering combined with a stabilization stage yielded ZnO:Al thin films with a nearly 2-fold improvement in crack initiation strain, which indicates greater resistance to bending. The critical strain of the optimal ZnO:Al films was ∼1.83%, which is a significant improvement compared to the current tolerance value of ∼1%. This was accompanied by a ∼300% improvement in fracture energy. We attributed the improved fracture behavior to the presence of residual compressive stresses, which creates a barrier for crack formation by acting opposite to the applied bending strain.
Original language | English |
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Pages (from-to) | 14654-14659 |
Number of pages | 6 |
Journal | ACS Applied Materials and Interfaces |
Volume | 7 |
Issue number | 27 |
DOIs | |
Publication status | Published - 2015 Jul 15 |
Bibliographical note
Publisher Copyright:© 2015 American Chemical Society.
All Science Journal Classification (ASJC) codes
- Materials Science(all)