论文标题
使用地形图像使用多尖扫描隧道显微镜的纳米级尖端定位
Nanoscale tip positioning with a multi-tip scanning tunneling microscope using topography images
论文作者
论文摘要
多尖端扫描隧道显微镜（STM）是在纳米级执行电荷传输测量的强大方法。有四个位于样品表面的STM尖端，可以以专用的几何配置进行四点电阻测量。在这里，我们提出了最经常使用的扫描电子显微镜（SEM）成像的替代方法，以推断相应的尖端位置。在通过光学显微镜监测的初始粗糙定位后，STM扫描本身用于确定尖端距离。大型STM概述扫描用作参考图。在参考图中识别相同的地形特征，并在带有各个尖端的小型图像中识别以大约20 nm的精度识别典型的尖端间距约为1 $μ$ m的位置。为了纠正诸如STM的压电元素的偏转，蠕变和磁滞之类的效果，必须进行仔细的校准。
Multi-tip scanning tunneling microscopy (STM) is a powerful method to perform charge transport measurements at the nanoscale. With four STM tips positioned on the surface of a sample, four-point resistance measurements can be performed in dedicated geometric configurations. Here, we present an alternative to the most often used scanning electron microscope (SEM) imaging to infer the corresponding tip positions. After initial coarse positioning monitored by an optical microscope, STM scanning itself is used to determine the inter-tip distances. A large STM overview scan serves as a reference map. Recognition of the same topographic features in the reference map and in small scale images with the individual tips allows to identify the tip positions with an accuracy of about 20 nm for a typical tip spacing of ~1 $μ$m. In order to correct for effects like the non-linearity of the deflection, creep and hysteresis of the piezo-electric elements of the STM, a careful calibration has to be performed.
