纳米尺度的材料具有许多不同于宏观体材料的奇特的物理和化学特性.了解纳米结构的物性随材料尺寸及形状的变化关系,对于设计和合成具有特定功能的纳米材料有重要的指导意义.静电力显微镜技术为研究微纳米尺度下材料的电学特性提供了强有力的工具.文章介绍了这种测量技术的基本原理,并列举了几种在静电力显微镜基础上发展起来的纳米材料电学性质的表征方法,包括探针特征电容的标定、表面电荷密度测量、薄膜材料中载流子密度测定等.这些实验方法扩展了静电力显微镜的应用领域,为深入研究纳米材料的性质和纳米器件的功能结构提供了丰富的技术手段.
Nanostructured materials possess interesting physical and chemical properties which may differ significantly from their macroscopic counterparts.Understanding the size and shape dependence of nanostructures is important to the rational design of nanomaterials with a desired functionality.Scanning probe microscopy and its derivatives provide unique opportunities to deepen our insight into the electrical characteristics of nanostructures.We have developed several new approaches based on electric force microscopy that enable quantitative characterization of the electrical properties of nanostructured materials.Some example applications include the measurement of the characteristic capacitance of the EFM tip,the surface charge density of materials,and the charge carrier density in graphene and ultrathin organic films.