Development of Self-Vibration and -Detection AFM Probe by using Quartz Tuning Fork

We developed a novel type of quartz tuning-fork probe that vibrates and detects its own probe deformation, for application to atomic force microscopy (AFM). This tuning-fork probe improves the AFM image resolution because of its high Q (quality) factor value. The tuning-fork probe has a sharp tip that was fabricated using anisotropic wet etching and a focused ion beam system. We evaluated the vibration properties of the tuning-fork in both the in-phase and anti-phase driving mode, and measured a Q factor value of 2808 in the anti-phase mode. We also confirmed that the tuning-fork probe is able to measure a 100 nm-step on a silicon surface by self-vibration and self-detection, without using external vibration and optical-detection mechanisms.