Kelvin Probe Force Microscopy kpfm

For kpfm the same ac voltage is applied to the cantilever which, however, is now strictly kept away from the sample surface in the true noncontact mode [30,31]. The oscillation amplitude is kept to below 10nmp p in order to improve the force resolution and avoiding elastic tip sample interaction due to tapping. The additional ac field exerted by the tip modulates the 

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Piezoresponse force microscopy (pfm) [11] and Kelvin probe force microscopy (kpfm) [9] were applied to deduce the polarization and local electric potential distribution over the whole cross section of the pzt sample (see Figure 12.3 and Figure 12.4) under static conditions as well as after switching. The details of our setup are described elsewhere [9,11],... 

The variation of the work function in the vertical direction of multilayers was investigated by Kelvin probe force microscopy (KPFM) on a fracture cross-section of a film deposited on a silicon substrate, shown in Fig. 2.18. This method is described in detail in [184]. A variation of the work function of about 60-100 meV is clearly seen from the bright-dark contrast as well... 

Fig. 2.18. Kelvin probe force microscopy (KPFM) picture of the cross-section of a modulation doped Zni- Mg CtAl/ZnO film on a silicon substrate. The contact potential is given relative to pyrolytic graphite ( = 4.07 eV). The local variation of the contact potential is shown on the left side, while the chemical composition, determined by SIMS is displayed on the right side. Deposition parameters p = 0.2Pa, P = 75Wrf, Tsub = 300°C, single layer thickness dZno = dZni xMgxO Ai = 160 nm...

For all nc-AFM measurements, a Kelvin probe force microscopy (KPFM) feedback controller was additionally activated for simultaneous topographic imaging [19]. In order to compensate for electrically or electronically induced artefacts, an ac voltage was applied between tip and sample and used in combination with lock-in techniques and a feedback controller to compensate for the contact potential difference (CPD) between tip and sample. With this method, nc-AFM is assiued to image the sample topography without any artefacts originating from different local surface potentials [20]. 

Figure 6. Surface potential of a DT-PFDT gradient and pure DT- and PFDT-SAM measured by means of Kelvin Probe Force Microscopy (KPFM) (The r-axis error bars represent the uncertainty of the position along the gradient sample).

Kelvin Probe Force Microscopy (KPFM or SKPFM) was derived from the development of the atomic force microscope (AFM) al-... 

It had been recognized early that a multitude of forces can act between the tip and the surface and this can be used to probe a variety of surface properties far beyond plain topography. The most prominent example of such a technique is the Kelvin probe force microscopy (KPFM) [122] that has been introduced as atomic force microscopy potentiometry as it allows high-resolution imaging of charges... 

KPFM Kelvin Probe Force Microscopy Dip-Pen Nano Lithography... 

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