Electromechanical Responses of a Piezoelectric Semiconducting Nanoplate With the Steigmann–Ogden Surface

Abstract

Piezoelectric semiconductors (PSCs) find widespread applications in smart electronic devices due to their unique combination of piezoelectric and semiconductive properties. With the increasing demand for smaller and more efficient electronic devices, the performance of their components needs to be carefully optimized, especially when they are scaled down to nanoscale sizes. Pioneering studies have demonstrated that surface elastic properties play a significant role in determining the mechanical performance of nanoscale materials and structures. Therefore, it is important to comprehensively investigate the effects of surface elasticity, including surface residual stress, surface membrane stiffness, and surface bending stiffness, on the electromechanical responses of a PSC nanoplate. Additionally, it is crucial to examine the influence of flexoelectricity at the nanoscale. Our results demonstrate that surface elastic properties predominantly impact mechanical performance, while the flexoelectric effect plays a more prominent role in electric field and redistribution of charge carriers. In particular, the significance of surface bending rigidity, which was often overlooked in previous literature, becomes pronounced when the thickness of a PSC nanoplate is less than 7 nm. Furthermore, the dependence of natural vibration frequency on surface elastic moduli, flexoelectricity, and size is, respectively, explored. The redistributions of electric potential and charge carriers across the cross section are also evidently affected. Our findings provide valuable insights for improving the performance of electronic devices that utilize nanoscale PSCs.