Calibration on force upon the surface of single ZnO nanowire applied by AFM tip with different scanning angles

Abstract

The mechanical service behaviors of ZnO nanowires (NWs) with diameters ranging from 67 to 201 nm and different scanning angles at a scanning rate of 14.8 μm s⁻¹ were studied by atomic force microscope (AFM). The force calibration equation was established between the actual forces applied on the surface of single ZnO NW, applied forces and scanning angles. It was proved that the actual forces strengthened when scanning angles exist. The actual fracture threshold forces increase linearly with the increase of diameters of the ZnO NWs, but do not dependent on the scanning angles. The force calibration is important and significant for applying forces accurately using AFM with scanning angles. The investigation provides a method for studying mechanical service behaviors of one dimensional nanomaterial under non-normal stress state and calibrating the actual force applied by AFM under different scanning angles.