Quantitative analysis of the resolution and sensitivity of Kelvin probe force microscopy using carbon nanotube functionalized probes

Carbon nanotube (CNT) functionalized probes are expected to offer better resolution in Kelvin probe force microscopy (KPFM) but are suspected of lower sensitivity because of the small area between the CNT end and the sample surface. This paper quantitatively analyzes the resolution and sensitivity of KPFM using CNT functionalized probes. First, point spread functions (PSFs) of CNT functionalized probes are derived for both amplitude-modulation and frequency-modulation detection in KPFM. Based on these PSFs, the resolution and sensitivity of KPFM using CNT functionalized probes are analyzed. The findings suggest that CNT functionalized probes offer better resolution and are sensitive enough under proper operational conditions. These findings provide practical guidance for designing and making CNT functionalized probes in KPFM applications.