WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
Department of Physics, Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
Rev Sci Instrum. 2022 Jan 1;93(1):013701. doi: 10.1063/5.0072722.
The Z-scanner is the major component limiting the speed performance of all current high-speed atomic force microscopy systems. Here, we present an ultrafast piezoelectric Z-scanner with a resonance frequency above 1.1 MHz, achieving a record response time of ∼0.14 µs, approximately twice as fast as conventional piezoelectric-based Z-scanners. In the mechanical design, a small piezo-stack is supported at its bottom four vertices on a cone-like hollow, allowing the resonance frequency of the Z-scanner to remain as high as that of the piezo in free vibration. Its maximum displacement, ∼190 nm at 50 V, is large enough for imaging bio-molecules. For imaging bio-molecules in a buffer solution, the upper half of the Z-scanner is wrapped in a thin film resistant to water and chemicals, providing an excellent waterproof and mechanical durability without lowering the resonance frequency. We demonstrate that this Z-scanner can observe actin filaments, fragile biological polymers, for more than five times longer than the conventional Z-scanner at a tip velocity of 800 µm/s.
Z 扫描器是限制所有当前高速原子力显微镜系统速度性能的主要组件。在这里，我们提出了一种超快压电 Z 扫描器，其共振频率超过 1.1 MHz，实现了创纪录的约 0.14 µs 的响应时间，大约是传统基于压电的 Z 扫描器的两倍快。在机械设计中，一个小的压电堆叠在一个锥形的空心底部的四个顶点上被支撑，使得 Z 扫描器的共振频率保持在自由振动中与压电的一样高。它的最大位移约为 190nm 在 50V 时，对于成像生物分子来说足够大。为了在缓冲溶液中成像生物分子，Z 扫描器的上半部分被包裹在一层抵抗水和化学物质的薄膜中，在不降低共振频率的情况下提供了出色的防水性和机械耐久性。我们证明，这种 Z 扫描器可以以 800 µm/s 的尖端速度观察肌动蛋白丝等脆弱的生物聚合物，比传统的 Z 扫描器观察时间长五倍以上。
