Abstract
In this paper we demonstrate that depending on the surrounding ambient, which may be manifested by different damping conditions, a "bump" in frequency response of Electric Force Microscope (EFM) cantilevers may be observed, either in electrical amplitude or phase signals of AC gradients. This bump is present in air and at room temperature when the cantilever oscillates at fundamental frequency with high excitation amplitude but disappears at increasing temperature. This effect can be explained by a significant temperature decrease of the Q factor of coated cantilevers. At a constant value of AC voltage, the relevant parameter is the ratio of Q factor by cantilever stiffness (of the nth oscillation mode) from which we can predict bump observation. This study highlights significant effects for quantitative EFM studies under different atmospheres and at different temperatures.