In-plane lattice strain evaluation in piezoelectric microcantilever by two-dimensional X-ray diffraction

Two-dimensional X-ray diffraction (XRD2) was applied to the in-plane strain evaluation of the piezoelectric microcantilever fabricated from the (001)-/( 100)-oriented Pb(Zr-0.52,Ti-0.48)O-3 film deposited on a (001)(c) LaNiO3/(111) Pt/TiO2/SiO2/Si/SiO2/(001) Si substrate under the applied voltage. In-plane lattice parameters were estimated using XRD2 results with two different diffractions originated from PZT, surface normal 002/200 diffract ions at chi = 0 and 45 degrees rotated 101/110 diffractions from surface normal (chi = 45 degrees). The out-of-plane and in-plane lattice parameters were linearly increased and decreased by increasing the applied voltage, regardless of the a- and c-axes. A significant 90 degrees-domain rotation from the a-domain to the c-domain was not observed in the microcantilever. The calculated transverse piezoelectric constants (d(31)) based on the in-plane strain, curvature, and z-displacement indicated similar values of about -140 +/- 10 pm/V. This result shows that the in-plane lattice strain mainly contributed to the displacement of the cantilever.