Chen Zhe, Luo Jiawei, Doudevski Ivo, Erten Sema, Kim Seong H
Department of Chemical Engineering, Pennsylvania State University, University Park, PA 16802, USA.
Materials Research Institute, Pennsylvania State University, University Park, PA 16802, USA.
Microsc Microanal. 2019 Oct;25(5):1106-1111. doi: 10.1017/S1431927619014697.
Atomic force microscopy (AFM) is typically used for analysis of relatively flat surfaces with topographic features smaller than the height of the AFM tip. On flat surfaces, it is relatively easy to find the object of interest and deconvolute imaging artifacts resulting from the finite size of the AFM tip. In contrast, AFM imaging of three-dimensional objects much larger than the AFM tip height is rarely attempted although it could provide topographic information that is not readily available from two-dimensional imaging, such as scanning electron microscopy. In this paper, we report AFM measurements of a vertically-mounted razor blade, which is taller and sharper than the AFM tip. In this case, the AFM height data, except for the data collected around the cutting edge of the blade, reflect the shape of the AFM tip. The height data around the apex area are effectively the convolution of the AFM tip and the blade cutting edge. Based on computer simulations mimicking an AFM tip scanning across a round sample, a simple algorithm is proposed to deconvolute the AFM height data of an object taller and sharper than the AFM tip and estimate its effective curvature.
原子力显微镜(AFM)通常用于分析相对平坦的表面,其形貌特征小于AFM探针的高度。在平坦表面上,相对容易找到感兴趣的物体,并对由AFM探针的有限尺寸产生的成像伪像进行去卷积。相比之下,对尺寸远大于AFM探针高度的三维物体进行AFM成像的尝试很少,尽管它可以提供二维成像(如扫描电子显微镜)不易获得的形貌信息。在本文中,我们报告了对垂直安装的剃须刀片的AFM测量,该刀片比AFM探针更高且更锋利。在这种情况下,AFM高度数据,除了在刀片刀刃周围收集的数据外,反映的是AFM探针的形状。顶点区域周围的高度数据实际上是AFM探针和刀片刀刃的卷积。基于模拟AFM探针扫描圆形样品的计算机模拟,提出了一种简单算法,用于对高于且锐于AFM探针的物体的AFM高度数据进行去卷积,并估计其有效曲率。