Physically Transient Threshold Switching Device Based on Magnesium Oxide for Security Application

Transient memristors are prospective candidates for both secure memory systems and biointegrated electronics, which are capable to physically disappear at a programmed time with a triggered operation. However, the sneak current issue has been a considerable obstacle to achieve high‐density transient crossbar array of memristors. To solve this problem, it is necessary to develop a transient switch device to turn the memory device on and off controllably. Here, a dissolvable and flexible threshold switching (TS) device with a vertically crossed structure is introduced, which exhibits a high selectivity of 10⁷, steep turn‐on slope of <8 mV dec⁻¹, and fast ON/OFF switch speed within 50/25 ns. Triggered failure could be achieved after soaking the device in deionized water for 8 min at room temperature. Furthermore, a water‐assisted transfer printing method is used to fabricate flexible and transient TS device arrays for bioresorbable systems, in which none of any significant degradation is observed under a bending radius of 2 mm. Integrating the selector with a transient memristor is capable of 10⁷ Gb memory implementation, indicating that the transient TS device could provide great opportunities to achieve highly integrated transient memory arrays.