原子力显微镜的有限元仿真模型

Finite Element Simulation Model of Atomic Force Microscope

原子力显微镜(AFM)是一种功能强大的工具,用于对纳米级表面的形貌,机械和磁性特性进行成像。因其高分辨率而被广泛用于成像不同种类的材料,如半导体材料和人体细胞。与接触模式AFM不同,轻敲模式仅在每个振荡周期中间歇性地与样品接触,这在很大程度上减少了扫描期间的样品损坏。本文基于模拟轻敲模式AFM的工作原理,通过COMSOL Multiphysics建立了3D模型,进行本征频率研究以计算悬臂的共振频率。在悬臂的自由端施加正弦载荷以激活悬臂在其谐振频率上的振动。仿真结果显示了悬臂梁的共振频率和位移曲线。

Atomic Force Microscope（AFM） is a powerful tool for imaging the topography, mechanical and magnetic properties of nanoscale surfaces. It is widely used to image different kinds of materials such as semiconductor materials and human cells due to its high resolution. Unlike the contact mode AFM, the tapping mode intermittently contacts the sample only during each oscillation period, which greatly reduces sample damage during scanning. Based on the working principle of the simulated tapping mode AFM, a 3 D model is established by COMSOL Multiphysics, and the eigenfrequency study is performed to calculate the resonant frequency of the cantilever. A sinusoidal load is applied to the free end of the cantilever to activate the vibration of the cantilever at its resonant frequency. The simulation results show the resonant frequency and displacement curve of the cantilever beam.