Systematic Analyses of Passive Vibration Isolation System for Atomic Force Microscopes

Atomic force microscope (AFM) is a powerful tool for imaging a wide range of materials with nanometer resolution, which is sensitive to mechanical vibration from the ground or buildings. For improving imaging performance, vibration isolation systems are often employed. Air tables are often used to attenuate the vibration transmission from ground to precision instruments, but it performs poorly for low-frequency vibration isolation. Suspending AFM using long common bungee cords is a simple and effective vibration isolation method which perform well in both low-frequency and high-frequency domain. However, it requires a lot of space and the bungee cords will failure when using a long time. Here we developed a vibration isolation system that uses linear steel springs to suspend the AFM for high precision imaging. The simplified model is used to explain how the spring constant and the damper affects the vibration isolation performance, through experiment the relationship between the spring constant and the damper was verified. The accelerometer and the AFM were employed to show the isolation performance, it shows the noise level of the AFM can be reduced from 71 pm to 21 pm. © 2021, Springer Nature Switzerland AG