School of Advanced Materials and Nanotechnology, Xidian University, 710071, Xi'an, Shaanxi, China.
Institute of Nanoscience and Nanotechnology, School of Materials and Energy, Lanzhou University, 730000, Lanzhou, Gansu, China.
Nat Commun. 2022 Feb 9;13(1):778. doi: 10.1038/s41467-022-28443-0.
Piezotronics with capacity of constructing adaptive and seamless interactions between electronics/machines and human/ambient are of value in Internet of Things, artificial intelligence and biomedical engineering. Here, we report a kind of highly sensitive strain sensor based on piezotronic tunneling junction (Ag/HfO/n-ZnO), which utilizes the strain-induced piezoelectric potential to control the tunneling barrier height and width in parallel, and hence to synergistically modulate the electrical transport process. The piezotronic tunneling strain sensor has a high on/off ratio of 478.4 and high gauge factor of 4.8 × 10 at the strain of 0.10%, which is more than 17.8 times larger than that of a conventional Schottky-barrier based strain sensor in control group as well as some existing ZnO nanowire or nanobelt based sensors. This work provides in-depth understanding for the basic mechanism of piezotronic modulation on tunneling junction, and realizes the highly sensitive strain sensor of piezotronic tunneling junction on device scale, which has great potential in advanced micro/nano-electromechanical devices and systems.
压电器件具有在电子/机器和人/环境之间构建自适应和无缝交互的能力，在物联网、人工智能和生物医学工程中具有重要价值。在这里，我们报告了一种基于压电器件隧道结（Ag/HfO/n-ZnO）的高灵敏度应变传感器，它利用应变诱导的压电电势来平行控制隧道势垒的高度和宽度，从而协同调节电子输运过程。压电器件隧道应变传感器在应变 0.10%时具有 478.4 的高开关比和 4.8×10 的高应变系数，比对照组中基于传统肖特基势垒的应变传感器以及一些现有的 ZnO 纳米线或纳米带传感器大 17.8 倍以上。这项工作为压电器件对隧道结的调制基本机制提供了深入的理解，并在器件尺度上实现了压电器件隧道结的高灵敏度应变传感器，在先进的微/纳机电系统中有很大的应用潜力。
