Slow Z-axis dynamics of Scanning Tunneling Microscope (STM) is a key contributing factor to the slow scan speed of this instrument. A great majority of STM systems use piezotube nanopositioners for scanning. The piezotube bulkiness along with the mass of STM tip assembly restrict the overall Z-axis bandwidth of the system to about 1 $kHz$ . This limited bandwidth slows down the STM response to the sample topography changes. In this paper, we report a microfabrication process to build a Microelectromechanical-System (MEMS) nanopositioner for Z-axis positioning in STM with a tenfold bandwidth, and a similar range of motion. The MEMS device features an integrated nanometer-sharp in-plane Si tip, compatible with conventional batch fabrication processes. In addition, a novel electrical isolation technique is developed to electrically isolate the tip from the rest of this device. This enables us to provide a separate routing for tunneling current signal, enabling potential applications in parallelism. The fabricated MEMS device achieves 1.6 $\mu m$ motion with its first in-plane resonance beyond 10 $kHz$ . The capability of this MEMS nanopositioner to replace the Z-axis of STMs is demonstrated through establishing controlled and stable tunneling current on a graphite sample in ambient conditions. [2020-0345]

中文翻译：

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具有集成尖端的MEMS纳米定位器，用于扫描隧道显微镜。

扫描隧道显微镜（STM）的Z轴动力学缓慢是该仪器扫描速度缓慢的关键因素。绝大多数STM系统使用压电管纳米定位器进行扫描。压电管的庞大体积以及STM吸头组件的质量将系统的整体Z轴带宽限制为大约1 $ kHz $ 。这种有限的带宽会减慢STM对样品形貌变化的响应。在本文中，我们报告了一种微细加工工艺，该工艺可以构建一个微机电系统（MEMS）纳米定位器，以便在STM中以十倍的带宽和类似的运动范围对Z轴进行定位。MEMS器件具有集成的纳米锐利的平面Si尖端，可与常规的批生产工艺兼容。另外，开发了新颖的电隔离技术以将尖端与该设备的其余部分电隔离。这使我们能够为隧穿电流信号提供单独的路由，从而实现潜在的并行应用。制成的MEMS器件达到1.6 $ \ mu m $ 首次面内共振超过10的运动 $ kHz $ 。通过在环境条件下在石墨样品上建立受控且稳定的隧穿电流，证明了该MEMS纳米定位器能够替代STM的Z轴。[2020-0345]