Supplementary Information

The supplementary material details the microfabrication process for cantilevers and clamped-clamped beams made of hafnium oxide. It explains the setup for measuring the flexoelectric coefficient using a Laser Doppler Vibrometer. Annealing tests are presented to show that different temperature profiles result in the crystallization of HfO2 into its tetragonal phase. Polarization-electric field (P-E) loop measurements confirm the non-ferroelectric nature of HfO2 and provide data to calculate its relative permittivity.