Flexoelectric Materials and Structures for M/NEMS

Recent research progress on flexoelectricity suggests that dramatic enhancement of effective piezoelectric properties desirable for advanced M/NEMS, in principle, is attainable through flexoelectric (FE) effect and scale effect. In this paper, the transverse flexoelectric coefficient μ₁₂ of barium strontium titanate (BST) microcantilevers with thicknesses ranging from 1.4 mm down to 30 μm was measured at room temperature. It was found that μ₁₂ remains to be constant (8.5 μC/m) for all fabricated microcantilevers. Effective piezoelectric coefficients of these microcantilevers were also calculated, indicating that significantly increased effective piezoelectric coefficients can be obtained from microcantilevers with thickness of microns and nanometers, which is promising for micro/nano electromechanical systems (M/NEMS).