Dielectric force microscopy: A new approach for observing charge behavior in nanomaterials

The behavior of charges transferring between the components of functional nanodevices would significantly impacts the physical/chemical process in the devices. Thus, comprehensively understanding the transfer behavior of electrons/ions in the operational devices is essential for optimizing the performance of functional nanodevices and exploring the application potential of nanomaterials. In general, the measurement results of field effect transistor(FET) present the statistic behavior of the carriers in the whole nanodevices, so the FET is powerless to observe the details of transfer process of charges. In addition, there are some drawbacks for the FET based on nanomaterials, such as difficult fabrication, complex electrode/nanomaterials contact and high costs. Therefore, we developed the dielectric force microscopy(DFM) to solve these problems. In this paper, we introduce the principle of DFM, and show some applications of interpreting how contactless DFM technique can quickly characterize the electrical properties of nanomaterials, such as one-dimension nanomaterials, nanoparticles and organic semiconducting film, with high spatial resolution. These applications demonstrate the capabilities of DFM for the characterization of the electrical properties of nanomaterials, and present the broad prospects of DFM in the research about the physical and chemical properties of nanomaterials and the performance of nanodevices.