CAS Center for Excellence in Nanoscience, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, P. R. China.
School of Chemistry and Chemical Engineering, Center on Nanoenergy Research, School of Physical Science and Technology, Guangxi University, Nanning 530004, P. R. China.
Sci Adv. 2023 Mar 10;9(10):eadd3310. doi: 10.1126/sciadv.add3310.
It is extraordinarily challenging to implement adaptive and seamless interactions between mechanical triggering and current silicon technology for tunable electronics, human-machine interfaces, and micro/nanoelectromechanical systems. Here, we report Si flexoelectronic transistors (SFTs) that can innovatively convert applied mechanical actuations into electrical control signals and achieve directly electromechanical function. Using the strain gradient-induced flexoelectric polarization field in Si as a "gate," the metal-semiconductor interfacial Schottky barriers' heights and the channel width of SFT can be substantially modulated, resulting in tunable electronic transports with specific characteristics. Such SFTs and corresponding perception system can not only create a high strain sensitivity but also identify where the mechanical force is applied. These findings provide an in-depth understanding about the mechanism of interface gating and channel width gating in flexoelectronics and develop highly sensitive silicon-based strain sensors, which has great potential to construct the next-generation silicon electromechanical nanodevices and nanosystems.
实现机械触发与当前硅技术之间的自适应和无缝交互，对于可调谐电子、人机接口和微纳机电系统而言，极具挑战性。在此，我们报告了 Si 型铁电晶体管（SFT），其可以创新性地将施加的机械动作转换为电控制信号，并实现直接机电功能。利用 Si 中应变梯度诱导的铁电极化场作为“栅极”，可大幅调节 SFT 的金属-半导体界面肖特基势垒高度和沟道宽度，从而实现具有特定特性的可调谐电子输运。这种 SFT 及其对应的感知系统不仅可以创造出高应变灵敏度，还可以识别机械力施加的位置。这些发现深入了解了铁电电子学中界面栅和沟道宽度栅的机制，并开发出了高灵敏度的基于硅的应变传感器，这对于构建下一代硅机电纳米器件和纳米系统具有巨大潜力。
