Analog Synapse Device With 5-b MLC and Improved Data Retention for Neuromorphic System

Abstract

This letter presents an investigation of analog synapse characteristics of a PCMO-based interface switching device with varying electrode materials. In comparison with the filamentary switching device having only 1-b storage and variability issues, the interface switching devices exhibit excellent electrical properties, such as 5-b (32-level) multi-level cell characteristics, wafer-scale switching uniformity, and scalability of the switching energy with device area. To improve data retention of the interface switching device, we propose a Mo electrode to increase the oxidation barrier height (similar to 0.4 eV) that, in turn, significantly improves the retention time and pattern classification accuracy of neural networks.