近日，美国加州大学圣迭戈分校Alex Frano团队揭示了由氧化薄膜压印到衬底上的动态不对称应变。相关论文于2026年7月23日发表在《科学》杂志上。

在薄膜-衬底体系中，衬底的作用通常被认为仅限于提供静态的机械约束。当薄膜发生结构变化并进而改变衬底时，两者间的动态相互作用通常被忽略。结合X射线与电子显微镜技术，研究组观察到二氧化钒薄膜中电致诱导形成的导电细丝，在下方蓝宝石衬底中产生了强烈的不对称应变。

这种不对称的衬底应变又反馈到薄膜中，并决定了细丝的扩展方向，揭示了薄膜-衬底动态相互作用在决定薄膜功能特性方面的重要性。此外，该应变印记向衬底内部传播了至少数十微米，超过薄膜厚度200倍以上，从而可能使衬底功能化，使其作为三维集成微电子架构中主动的机械耦合介质发挥作用。

附：英文原文

Title: Dynamic asymmetric strain imprinted into substrates by an oxide thin film

Author: 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

Issue&Volume: 2026-07-23

Abstract: 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 an electrically induced filament in a vanadium dioxide film created strong asymmetric strain in an underlying sapphire substrate. 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 micrometers deep into the substrate, exceeding the film thickness by more than 200-fold, potentially enabling substrate functionalization as an active mechanical coupling media in three-dimensional integrated microelectronic architectures.

DOI: adt9347

Source: https://www.science.org/doi/10.1126/science.adt9347