Measurement Simulation of Nanoscale Semicircle Profile by Constant-Amplitude Tapping Mode Atomic Force Microscopy (TM-AFM) and Influence of Probe Shape on Scanning Profile

Abstract

This article mainly analyzed and developed a nanoscale simulative measuring model of constant-amplitude Tapping Mode Atomic Force Microscopy (TM-AFM) for simulating a nanoscale semicircle sample profile. By using the lattices of silicon (Si) atoms, the atomic models for TM-AFM rectangular cantilever probe tip and a semicircle sample could be arranged. Morse force was adopted to calculate the action force between the sample and the probe. Also using the induced TM-AFM vibration equation, the study constructed a TM-AFM constant-amplitude nanoscale simulative measuring model.The established TM-AFM constant-amplitude nanoscale simulative measuring model was used to simulatively measure the appearance of a semicircle sample and analyzed the results of error. The simulation results were compared with the curve of the ideal semicircle sample, so as to verity the rationality of the simulative measuring model developed by this study. At the same time, focusing on the different probes having the same probe tip radius but different bevel-angled shapes, the study used an ideal semicircle nanoscale sample to perform simulative measurement by TM-AFM, and investigated the influence of the probes with shapes at different bevel angles on the simulation curves of the semicricle profiles. As found in the research results, the error between the simulatively scanned semicircle profile and the ideal semicircle profile was mainly caused by the influence of the geometric shape of the simulated probe and the surface appearance of the semicricle sample.