title: Dual-functional Memory and Threshold Resistive Switching Based on the Push-Pull Mechanism of Oxygen Ions.
abstract: The combination of nonvolatile memory switching and volatile threshold switching functions of transition metal oxides in crossbar memory arrays is of great potential for replacing charge-based flash memory in very-large-scale integration. Here, we show that the resistive switching material structure, (amorphous TiOx)/(Ag nanoparticles)/(polycrystalline TiOx), fabricated on the textured-FTO substrate with ITO as the top electrode exhibits both the memory switching and threshold switching functions. When the device is used for resistive switching, it is forming-free for resistive memory applications with low operation voltage (<± 1 V) and self-compliance to current up to 50 μA. When it is used for threshold switching, the low threshold current is beneficial for improving the device selectivity. The variation of oxygen distribution measured by energy dispersive X-ray spectroscopy and scanning transmission electron microscopy indicates the formation or rupture of conducting filaments in the device at different resistance states. It is therefore suggested that the push and pull actions of oxygen ions in the amorphous TiOx and polycrystalline TiOx films during the voltage sweep account for the memory switching and threshold switching properties in the device.
authors.affiliation: Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan.
authors.forename: Yi-Jen
authors.initials: YJ
authors.lastname: Huang
authors.affiliation: Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan.
authors.forename: Shih-Chun
authors.initials: SC
authors.lastname: Chao
authors.affiliation: Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan.
authors.forename: Der-Hsien
authors.initials: DH
authors.lastname: Lien
authors.affiliation: Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan.|Taiwan Consortium of Emergent Crystalline Materials, Ministry of Science and Technology, Taipei 10617, Taiwan.
authors.forename: Cheng-Yen
authors.initials: CY
authors.lastname: Wen
authors.affiliation: Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division, King Abdullah University of Science &Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
authors.forename: Jr-Hau
authors.initials: JH
authors.lastname: He
authors.affiliation: Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan.
authors.forename: Si-Chen
authors.initials: SC
authors.lastname: Lee