【摘要】 利用粘有光纤探针的石英调谐音叉,可实现近场扫描光学显微镜(NSOM)和调谐音叉剪切力显微镜(TSM)光纤探针尖端与样品(T-S)间距离的控制。研究了石英调谐音叉控制T-S间剪切力作用的机制,建立了音叉T-S系统的振动方程,理论分析了音叉电流I和T-S间距d的关系,建立了T-S间剪切力作用机制模型。实验测量了不同环境和不同样品下的I-d曲线,实验结果与理论分析相吻合。揭示了nm尺度下,由于毛细凝聚作用在T-S间耦合的H2O和C-H化合物分子所形成的粘滞阻尼是导致T-S间剪切力作用的主要原因。更多还原

【Abstract】 The distance between tip and sample(T-S) can be regulated using piezo-electric quartz fork glued with micro optic fiber probe.The principle of this technology is studied.The biquadrate vibration equation for fork-probe-sample system is established,the relations between the electric current of the fork and T-S distance (I-d curves) are analysed theoretically,and the mechanism model of the shear force between the optic fiber probe and the sample is established.In this work the I-d curves of various samples under various conditions are measured.The results accord with the theoretical analyses very well.Furthermore,the intrinsic reasons for shear force damping between T-S have been revealed i.e.the water and hydrocarbon coupled between optic fiber probe and sample due to the capillary cohesion force.更多还原