Dynamic asymmetric strain imprinted into substrates by an oxide thin film
- Elliot Kisiel
- Alexandre Pofelski
- Pavel Salev
- Erbin Qiu
- Spencer Reisbick
- Chuhang Liu
- Andreas Glatz
- Ishwor Poudyal
- Wei He
- Rourav Basak
- Kaan Alp Yay
- Junjie Li
- Umeshkumar Patel
- Zhan Zhang
- Arndt Last
- Yimei Zhu
- Ivan K. Schuller
- Zahir Islam
- Alex Frano
2026-06-18
In film-substrate systems, the substrate role is often considered to be limited to providing static mechanical constraints. Dynamic film-substrate interactions when a structural change in the film modifies the substrate are generally disregarded. Using combined X-ray and electron microscopies, we observed that the electrically induced filament in a VO 2 film created strong asymmetric strain in the underlying Al 2 O 3 substate. This asymmetric substrate strain fed back into the film and defined the filament expansion direction, revealing the importance of film-substrate dynamic interactions in determining film functionality. Furthermore, the strain imprint propagated at least tens of microns deep into the substrate, exceeding the film thickness more than 200 times, potentially enabling substrate functionalization as an active mechanical coupling media in 3D-integrated microelectronics architectures.