Wear of the atomic force microscope tip under light load, studied by atomic force microscopy

Abstract

The purpose of this paper was to study the wear process of the non-conductive microfabricated silicon nitride (Si 3N 4) AFM tip which occurs during apparently wearless light-loaded scanning of the smooth silicon surface. AFM tip shape and wear were imaged using an AFM tip of the same size and geometry. Study included the observation of initial and worn surfaces, detecting of probing tip destruction and worn area size calculations. Scanning of the flat silicon surface with relatively low nominal load of 10 nN resulted in wear of the tip without significant drop in the quality of AFM image, possibly, because of formation of rough surface with asperities, acting as a probing tip. Wear mechanisms of the tip were analyzed. Low-cycle fatigue process, resulting in surface fracture, was found the most probable wear mechanism of the Si 3N 4 AFM tip.