Mechanically tunable Schottky diodes based on silicon microstructure arrays via flexoelectricity

Abstract

Silicon is the most widely used semiconductor material, yet its centrosymmetric crystal structure makes seamless interaction between mechanical stimuli and electronic functionality challenging. Flexoelectricity—an electromechanical coupling inherent in all types of crystals—offers a solution by leveraging strain gradient-induced polarization to modulate electronic behavior. In this study, silicon microfabrication techniques are integrated with flexoelectricity to realize tunable Schottky diodes. Microstructure arrays fabricated on p-type silicon generate substantial strain gradients under macroscopic compression without relying on nanoscale probes. The strain gradients induce polarization at the metal–semiconductor interface, modulating the Schottky barrier height and thereby enabling mechanical tuning of the diode's electrical properties. The results herein demonstrate that macroscopic loading can effectively regulate the current–voltage (I–V) characteristics. This work bridges the gap between the flexoelectric effect and practical semiconductor applications, paving the way for next-generation smart materials and adaptive electronic devices.