Effect of Au electrode on the resistance change response of HfOx-based ReRAM device under voltage pulse trains. (1st October 2022)

• Record Type: Journal Article
• Authors: Shingubara, S.; Huang, C.Y.; Hatanaka, R.; Shimizu, T.; Ito, T.
• Is Part Of: Japanese journal of applied physics. Volume 61:Number SM(2022)
• Publication Date: 2022-10-01
• Subjects: neuromorphic computing -- ReRAM -- Au electrode -- synaptic device -- artificial neuron -- HfOx -- diffusion; Physics -- Periodicals; 621.05
• DOI: 10.35848/1347-4065/ac7bf5
• Languages: English
• ISSNs: 0021-4922

Abstract

Abstract: The demand for neuromorphic computing is increasing, and resistive random access memory (ReRAM) devices are intriguing candidates for synaptic applications. We studied a Ti/HfO x /Au ReRAM device with this potential in view, and fabricated a Ti/HfO x /Pt device for comparison. Both devices exhibited bipolar switching characteristics. In response to voltage pulse trains, gradual resistance change was observed in the Ti/HfO x /Au device for both the SET and RESET processes, indicating its suitability for artificial synapse application. In contrast, an abrupt resistance change was observed in the SET process of the Ti/HfO x /Pt device. A significant diffusion of Au atoms occurred in the HfO x layer of the Ti/HfO x /Au device, and the Au atoms were oxidized at the interface. This led to an increase in the O vacancy concentration, which assisted the achievement of the gradual resistance change. The present study indicates that the Ti/HfO x /Au device demonstrates good potential for use as an artificial synaptic device.