Agilent 5991-3183EN Surface Potential Measurements Using the Keysight 7500 AFM - Application Note c20141020 free download

File name 5991-3183EN Surface Potential Measurements Using the Keysight 7500 AFM - Application Note c20141020

Keysight 5600LS AFM Surface Potential Measurements Using Keysight 7500 AFM Application Brief Introduction cantilever, respectively. lows the Keysight 7500 AFM to perform single-pass KFM measurements by ap- Scanning kelvin force microscopy (KFM) The force component at 2v is proportion- plying dual-frequency excitation signals has been widely used in mapping surface al to dC/dZ. Therefore, by mapping the to the AFM tip simultaneously. One potential (SP) distribution at the na- F2v response one can get spatial varia- excitation signal is used for modulating noscale. The principle of KFM is based on tions of local dielectric behavior. In other the mechanical oscillation of the AFM tip the measurement of electrostatic forces words, KFM can provide an advanced and for topography imaging. The second between the tip and the surface. When a characterization of local electric and excitation signal is applied for the modu- dc bias (Vdc) and a small ac modulation dielectric properties. lation of the AFM-based electrostatic signal Vac sin vt are applied between the tip-sample force, and is used for the tip and the sample, the induced capaci- Instrumentation measurement of sample surface poten- tive force is tial. The 3rd LIA can be set for monitor- The Keysight Technologies, Inc. 7500 ing various signals, e.g., F2v for dC/dZ AFM/SPM microscope is a high- imaging. Detailed instrumental setup/ performance instrument that delivers operation are available in other Key- high resolution imaging with integrated sight documents. A number of practical environmental control functions. The examples are shown below to demonstrate standard Keysight 7500 includes contact the application of Keysight 7500 AFM in high (1) mode, acoustic AC mode, and phase resolution surface potential measurement where f is the contact potential dif- imaging that comes with one universal and spatial mapping of dielectric properties ference (CPD) between the tip and the scanner operating in both Open-loop and over the sample surface. sample. It is evident from the Fv term Closed-loop mode. Switching imaging modes with the Keysight 7500 AFM/SPM in Equation