Ar-Plasma-Modulated Optical Reset in the SiO2/Cu Conductive-Bridge Resistive Memory Stack. (20th July 2018)

• Record Type: Journal Article
• Authors: Kawashima, Tomohito; Yew, Kwang Sing; Zhou, Yu; Ang, Diing Shenp; Zhang, Haizhong; Kyuno, Kentaro
• Is Part Of: ECS transactions. Volume 86:Number 3(2018)
• Page Start: 55
• Page End: 64
• Publication Date: 2018-07-20
• Subjects: Electrochemistry -- Periodicals; Electrochemistry; Periodicals; Electronic journals; Electronic journal; 541.37
• DOI: 10.1149/08603.0055ecst
• Languages: English
• ISSNs: 1938-5862

Abstract

Abstract : Our study using conductive atomic force microscope shows that the resistive switching voltage in the SiO2 /Cu stack is reduced by 33% after Ar plasma treatment of the oxide. Besides, the negative photo-conductivity (NPC) effect, normally observed on many locations following electrical soft-breakdown, is suppressed. The NPC effect arises because the electrically-formed filamentary conductive path, comprising both Cu and oxygen vacancies, may be disrupted by the recombination of the vacancies with nearby light-excited interstitial oxygen ions. Increase of the O-H peak, as seen from FT-IR spectroscopy, indicates that surface defects generated by the Ar plasma may have adsorbed water molecules, which in turn act as counter anions (OH − ) accelerating Cu-ion diffusion into the oxide, forming a more complete Cu filament that is non-responsive to light. The finding offers the possibility of both electrical and optical resistance control by a simple surface treatment step.