Nanoelectromechanical Switches by Controlled Switchable Cracking

Nanoelectromechanical (NEM) switches could surmount the Boltzmann Tyranny in the current charge-carrier systems. However, thus far, practical implementations of the NEM systems have been hindered by the complicated fabrication processes of forming the extremely small air gap. Here, we realize a very simple NEM switch by exploiting a switchable nanocrack controlled by an electric field in a metallic alloy-ferroelectric heterostructure. The crack is formed in a controllable manner in terms of its initiation, location, and orientation through a bridge-like structure. The open and closed states of the crack are programmed under a cyclic electric field. In addition, an abrupt switching behavior with a nonvolatile high ON/OFF current ratio (>10⁷) is measured owing to the near-zero OFF-state leakage current across the crack. This simple nanocrack switch presents a novel opportunity in the NEM systems, which can be used as a new nonvolatile random-access memory and logic.