UV-laser annealing for improved resistive switching performance and reliability of flexible resistive random-access memory

Flexible resistive random-access memory (RRAM) has attracted significant attention owing to the strong demand for various flexible electronic memory devices. However, fabricating reliable and flexible RRAM is a significant challenge because of the inherently high thermal sensitivity of plastic substrates. In this study, a high-performance flexible RRAM device was fabricated without deforming a plastic substrate by utilizing a precisely controlled UV laser annealing process. The application of laser annealing in an Al/ZnO/Al flexible RRAM changes the concentration of O Frenkel defect pairs in the ZnO layer and produce a ZnO/Al mixed interface layer with high quality oxygen reservoirs. The higher concentration of O Frenkel defect pairs in the ZnO layer induces electroforming-free process, and the improved characteristics such as crystallinity, morphology, and stoichiometry of the interface area result in stable resistive switching and performance enhancement in the flexible RRAM. The laser-annealed flexible RRAM exhibits a high on/off ratio (~1.07 x 10(4)), high cycling endurance (up to 2.5 x 10(3) cycles), and low power consumption (4.88 mu W in SET state and 1.21 mu W in RESET state). Importantly, the performance was maintained at a bending radius of up to 5 mm. (C) 2022 Elsevier B.V. All rights reserved.

Automated summary

This study fabricates a high-performance flexible RRAM device using a precisely controlled UV laser annealing process, which changes the concentration of O Frenkel defect pairs in the ZnO layer and produces a ZnO/Al mixed interface layer with high quality oxygen reservoirs. The laser-annealed flexible RRAM shows stable resistive switching, performance enhancement, high on/off ratio, cycling endurance, and low power consumption, even at a bending radius of up to 5 mm.