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原子力显微镜(atomic force microscope,AFM)具有极高的观测分辨率和作业精度,在纳米材料表征与纳米器件组装方面发挥了不可替代的作用.AFM工作区域的选取依赖于光学显微镜,受可见光波波长的限制,光学显微镜的分辨率一般不超过200 nm,这导致光学显微镜无法有效辨识AFM观测目标样本所在的区域.当样本被移动或者更换AFM扫描探针引起样本与探针针尖的相对位置发生变化时,如何重新将AFM探针精确定位到原观测/操作区域具有非常大的挑战性.本文研究提出了一种新的免标记探针重定位方法,综合考虑了样本角度旋转与位置偏移两个因素,首先利用光学显微镜选取样本基底上易于识别的自然特征作为参照点,基于坐标变换原理实现微米级精度的探针盲定位,进而通过AFM扫描图像的匹配获得X-Y水平方向的位置偏差,通过修改AFM的扫描参数实现纳米目标的原位快速精确重定位.该方法的优点在于不需要在纳米目标样本操作区域上制作特殊的标记,操作过程简单、定位快速、定位范围较广且具有极高的重定位精度.对纳米小球、单壁碳纳米管(single-walled carbon nanotubes,SWCNTs)、纳米划痕等样本的重定位实验验证了该方法的实用性和高效性.
Atomic force microscope (AFM) has an extremely high resolution and accuracy, and plays an irreplaceable role in nanomaterials characterization and assembly of nanodevices. The selection of AFM work area depends on the optical microscope, which is affected by the wavelength of visible light , The resolution of the optical microscope is usually not more than 200 nm, which makes it impossible for the optical microscope to effectively identify the area where the AFM observes the target sample. When the sample is moved or the AFM scanning probe is replaced, the relative position between the sample and the probe tip is changed , How to re-locate the AFM probe accurately to the original observation / operation area is very challenging.In this paper, we propose a new tag-free probe relocation method that takes into account both the sample angle rotation and the position shift two Firstly, the natural features that are easy to identify on the sample base were selected as the reference points by optical microscope. Then the blind positioning of the probe with micrometer accuracy was realized based on the principle of coordinate transformation. Then the horizontal deviation of XY position was obtained by matching the AFM images. Modify the scanning parameters of AFM to realize rapid and accurate resetting of nanometer target in situ Bit.The advantage of this method is that it does not need to make special mark on the operation area of nano-target sample, the operation process is simple, the positioning is fast, the positioning range is wide and the positioning accuracy is very high.For nanosphere, single-walled carbon nano The relocation experiments of single-walled carbon nanotubes (SWCNTs) and nano-scratch verify the practicability and efficiency of this method.