Wang Fei, Zhao Xuezeng
School of Mechanical and Electronic Engineering, Harbin Institute of Technology, Harbin, China.
Rev Sci Instrum. 2007 Apr;78(4):043701. doi: 10.1063/1.2720723.
Quantitative friction measurement of nanomaterials in atomic force microscope requires accurate calibration method for lateral force. The effect of contact stiffness on lateral force calibration of atomic force microscope is discussed in detail and an improved calibration method is presented. The calibration factor derived from the original method increased with the applied normal load, which indicates that separate calibration should be required for every given applied normal load to keep the accuracy of friction measurement. We improve the original method by introducing the contact factor, which is derived from the contact stiffness between the tip and the sample, to the calculation of calibration factors. The improved method makes the calculation of calibration factors under different applied normal loads possible without repeating the calibration procedure. Comparative experiments on a silicon wafer have been done by both the two methods to validate the method in this article.
在原子力显微镜中对纳米材料进行定量摩擦测量需要精确的横向力校准方法。详细讨论了接触刚度对原子力显微镜横向力校准的影响，并提出了一种改进的校准方法。原始方法得出的校准因子随所施加的法向载荷增加，这表明对于每个给定的施加法向载荷都需要单独校准以保持摩擦测量的准确性。我们通过将源自针尖与样品之间接触刚度的接触因子引入校准因子的计算中，对原始方法进行了改进。改进后的方法使得在不同施加法向载荷下无需重复校准过程即可计算校准因子成为可能。已通过这两种方法对硅晶片进行了对比实验，以验证本文中的方法。
