Development of an improved Kelvin probe force microscope for accurate local potential measurements on biased electronic devices

Summary An improved setup for accurate near‐field surface potential measurements and characterisation of biased electronic devices using the Kelvin Probe method has been developed. Using an external voltage source synchronised with the raster‐scan of the KPFM‐AM, this setup allows to avoid potential measurement errors of the conventional Kelvin Probe Force Microscopy in the case of in situ measurements on biased electronic devices. This improved KPFM‐AM setup has been tested on silicon‐based devices and organic semiconductor‐based devices such as organic field effect transistors (OFETs), showing differences up to 25% compared to the standard KPFM‐AM lift‐mode measurement method. Lay description This work presents the development of a Kelvin Probe Force Microscopy (KPFM) technique able to measure the surface electrical potential of biased devices with a higher accuracy and sensitivity than the equivalent existing techniques, which neglect the effect of the sample biasing while measuring the potential. This kind of measurements of biased devices finds applications in the field of semiconducting transistors, from the fundamental point of view to the final application. In particular, in the organic electronic devices, which represent an emerging field of research, an accurate mapping of the electrical potential with a resolution in the order of tens of nanometres can be extremely helpful for the characterisation and optimisation of the biasing devices at high vol...
Source: Journal of Microscopy - Category: Laboratory Medicine Authors: Tags: Original Article Source Type: research