Wang Yu-Liang, Zhao Xue-Zeng
School of Mechatronic Engineering, Harbin Institute of Technology, Harbin 150001, People's Republic of China.
Rev Sci Instrum. 2009 Feb;80(2):023704. doi: 10.1063/1.3079685.
The atomic force microscopy (AFM) can provide tribological information in micro/nanoscale. However, the general measurement techniques require rigorous value of stiffness and relationship between AFM cantilever deformation and corresponding photodetector response. In this study, triangular AFM cantilevers with different dimensions are applied to quantitatively measure the coefficient of friction with the improved parallel scan method [Y. L. Wang, X. Z. Zhao, and F. Q. Zhou, Rev. Sci. Instrum. 78, 036107 (2007)]. An analytical model is first presented with the plan-view geometrical dimensions of cantilevers. Finite element analysis (FEA) models are set up to validate the analytical model. The results show good agreement between analytical calculation and FEA simulation. More importantly, the coefficient of friction obtained with different cantilevers on silicon surface shows a good consistency. At last, the factors which may affect measurement are discussed. The advantage of the model presented here is that the general uncertainties of thickness and Young's modulus are not necessary to be known for the friction force calibration in AFM application.
原子力显微镜（AFM）能够在微纳尺度上提供摩擦学信息。然而，一般的测量技术要求严格的刚度值以及AFM悬臂梁变形与相应光电探测器响应之间的关系。在本研究中，采用不同尺寸的三角形AFM悬臂梁，通过改进的平行扫描方法[Y. L. Wang, X. Z. Zhao, and F. Q. Zhou, Rev. Sci. Instrum. 78, 036107 (2007)]来定量测量摩擦系数。首先根据悬臂梁的俯视几何尺寸建立了一个分析模型。建立了有限元分析（FEA）模型来验证该分析模型。结果表明分析计算与FEA模拟结果吻合良好。更重要的是，不同悬臂梁在硅表面获得的摩擦系数显示出良好的一致性。最后，讨论了可能影响测量的因素。这里提出的模型的优点是，在AFM应用中进行摩擦力校准时，不必知道厚度和杨氏模量的一般不确定度。
