Developmet of Wide Range Tribo-Tester Using Scanning Probe Technique

为了使用扫描探针方法评估表面的摩擦学特性，对探针施加的力的范围，测量的垂直和水平力的明确分离以及尖端抗滑动运动的高耐久性是必不可少的。为此，选择了一个带有金刚石尖端的悬臂。首先，提出了一种具有垂直力和水平力分别测量功能的新型悬臂结构。这种结构的特别之处在于，从一个基础杠杆延伸出两个杠杆，并与一个顶端有菱形尖端的横向杆相连。经证实，该结构允许分别使用来自双杠杆的差分信号和来自基础杠杆的直接信号来测量扭转和垂直位移。其次，采用迈克尔逊激光干涉测量法测量悬臂梁的三维位移。利用超高速VTR捕捉悬臂表面形成的条纹图案，然后对图像数据进行分析，同时提供垂直和水平力。最后，制备了掺杂n型原子的硅悬臂梁，用于直接测量悬臂梁应变的力。通过实验明确了悬臂梁的线性度和灵敏度，并利用悬臂梁的共振特性确定了悬臂梁的刚度和有效质量等力学特性。

To evaluate tribological characteristics of surface using the scanning probe method, wide range of applying forces to the probe, clear separation in measured vertical and horizontal forces and high durability of tip against sliding motion are essential. For this purpose, a cantilever with a diamond tip glued onto it was selected.First, a novel cantilever structure having a function for measuring vertical and horizontal forces separately was proposed. Special feature of this structure was twin levers extended from a base lever and bridged with a top lateral bar having a diamond tip. This structure was confirmed to permit torsional and vertical displacements to be measured separately using differential signal from the twin levers and direct signal form the base lever.Second, the Michelson laser interferometry was applied for measuring three-dimensional displacement of the cantilever. Fringe pattern formed over the cantilever surface was captured using a ultra-high speed VTR,then the image data were analyzed to provide vertical and horizontal forces, simultaneously.Finally, a silicon cantilever doped with N-type atoms was fabricated for directly measuring the force from the cantilever strain. Linearity and sensitivity were experimentally clarified, and mechanical characteristics, such as, stiffness and effective mass were identified using resonance of the cantilever.