(a) The deflection profiles along the NW sample length under AFM contact mode. (Left) For an NW with diameter of 65.9 nm (small diameter), the deflection profile was fitted best with doubly clamped boundary condition; (right) for an NW with diameter of 125.5 nm (large diameter), the deflection profile was fitted better with simply supported boundary condition. (Reprinted with permission from Chen et al. [59]. Copyright 2006 American Institute of Physics.) (b) The resonance frequency as a function of the clamp size for a ZnO NW under resonance in SEM. (Left) The resonance peaks for different clamp sizes, and (right) the resonance frequency increases with the increasing clamp size. (Reproduced with permission from Qin et al. [61]. Copyright 2012 by Wiley).