Figure 1.

Deflection ξ, slope ξ′, and curvature ξ″ of a curved cantilever of length ℓ and width w. Plots (a), (b), and (c) give the dimensionality D, derived from finite element calculations [25] for an isotropic substrate under isotropic biaxial stress for deflection, slope and curvature measurements, respectively. A direct curvature measurement is preferable, as it requires the smallest corrections for length-to-width ratios larger than two. The different plots within each panel indicate the dependence of D on the magnitude of the Poisson ratio v.