Design and realization of scanning probe microscope based on a T-shaped high-aspect-ratio probe

Abstract

With the growing importance of three-dimensional (3D) nanomaterials and devices, the use of high-aspect-ratio (HAR) probes in atomic force microscopy (AFM) imaging enables full-profile topography characterization. However, HAR-AFM probes are difficult to manufacture due to the expensive materials and complex processes. Inspired by the Wollaston scanning probe, we successfully fabricated a T-shaped tungsten probe and installed in a home-built scanning probe microscope (SPM) system. Compared with commercial AFM, the self-developed platform utilizes a set of LabVIEW control programs based on Field Programmable Gate Array (FPGA) hardware feedback, which improves the scanning speed and makes the control program more flexible. The reliability of the system was verified by comparing with the scanning results of commercial AFM. The T-shaped probe exhibits better fidelity in HAR-hole imaging compared to AFM standard pyramidal probes. This approach will likely find a convenient and material-saving fabrication route, especially for custom functional nanoprobes.