Novel method for high speed force curve measurement considering cantilever dynamics for atomic force microscopy

Atomic Force Microscopy (AFM) is a scanning probe microscope with nanoscale resolution as well as an indispensable device for nanotechnology. Since AFM probe physically touches the sample surface, expectations for sample dynamics measurement are raising. One common measurement mode is force curve measurement. In the force curve measurement, atomic force is detected by the spring constant of the cantilever. In high speed measurement, however, the cantilever oscillates with its resonance frequency and cannot detect the atomic force. This paper proposes novel methods to identify cantilever dynamics and to measure the force curve in high speed using atomic force observer (AFO) and the effectiveness of the proposed measurement method was demonstrated by simulations and experiments. Furthermore, the robustness of the AFO against modeling error is discussed.