音叉式AFM探针针尖与表面接近特性的研究

Study on Approaching Characteristics between the Tip and the Surface of Atomic Force Microscope Based on Tuning Fork Probe

基于音叉式探针的特性,建立了探针针尖与样品表面接近过程中的动力学方程,并利用Simulink软件模拟了该过程中探针悬臂振幅响应情况。搭建了基于音叉探针的接近曲线检测装置,使用位移系统控制程序和锁相放大器数据采集程序,在调幅模式下获得探针在不同激励电压下的接近曲线,在调幅模式下获得探针在不同激励电压下的接近曲线,探针在25,50,75,100 m V的激励下,工作距离分别为4. 12,5. 1,5. 95,7. 6nm,结果与仿真相符。

In the study of atomic force microscopy,the micro-force detection in the approaching process between the tip and the sample is the basis for accurate measurement of the sample morphology. A dynamic equation was established based on the characteristics of tuning fork probe and Simulink software was used to simulate the amplitude response.Experimental device of approaching curve and program of controlling displacement system and acquiring data from lock-in amplifier were designed independently. In the AM mode,the curves under different excitation voltages were obtained.Under the excitation of 25,50,75 and 100 m V,the working distance of the probe is 4. 12,5. 1,5. 95,7. 6 nm respectively,and the forms are in conformity with the simulation.