Journal of Applied Physics has published an article written by Izzat Aziz, Jing-Hao Ciou, Haruethai Kongcharoen, and Pooi See Lee, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
Abstract: “Resistive random access memory (ReRAM) is touted to replace silicon-based flash memory due to its low operating voltage, fast access speeds, and the potential to scale down to nm range for ultra-high density storage. In addition, its ability to retain multi-level resistance states makes it suitable for neuromorphic computing application. Here, we develop a cationic ReRAM with a sputtered MgO as the insulating layer. The resistive switching properties of the Ag/MgO/Au ReRAM stack reveal a strong dependence on the sputtering conditions of MgO. Due to the highly stable sputtered MgO, repeatable resistive switching memory is achieved with a low ON voltage of ∼0.7 V and a memory window of ∼1 × 105. Limiting Ag diffusion through a modified top electrode in the W/Ag/MgO/Au stack significantly reduces the abruptness of resistive switching, thereby demonstrating analog switching capability. This phenomenon is evident in the improved linearity and symmetry of potentiation and depression weight modulation pulses, demonstrating ideal Hebbian synaptic learning rules.“
This project was supported in part by the IAF-ICP Project under Grant No. I1801E0030 and the NRF Investigatorship under Grant No. NRF-NRFI2016-05.