Article

Influence of deposition pressure of CuTe electrode on the tantalum oxide-based resistive switching memory

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Abstract

The resistive switching characteristics of Pt/TaO x /CuTe devices were investigated with CuTe bottom electrodes deposited under different working pressure. The CuTe bottom electrode was prepared using a magnetron radio-frequency sputtering. The resistance and distribution of HRS were decreased with increasing deposition pressure of CuTe bottom electrode and then the resistance of LRS was increased however the distribution of LRS was unchanged. The CuTe bottom electrode was systematically analyzed to identify the effect of deposition condition on resistive switching behavior. The intermixing between the TaO x layer and CuTe bottom electrode was clearly identified as an active factor causing the variation of resistive switching parameters.

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... CBRAM is a new type of resistive random access memory (RRAM) [6]. The mechanism of CBRAM can be manifested by the electrochemical formation and rupture of a metal-ion based conductive filament (CF) in the switching layer [7,8]. Recently, various amorphous metal oxide semiconductors (AOS), such as ZnO, GZO, IGZO, and IWZO have been properly used as switching layer materials for CBRAM [9][10][11][12]. ...
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Various classes of resistive random access memory (RRAM) classes involving chemical effects related to redox processes in the MIM cell are presented. The electrochemical metallization (ECM) cells systems involve Ag and Cu as electrochemically active metals and phase separated amorphous selenides and sulfides and various oxides, acting as solid electrolytes. The polarity of the bipolar switching cycle is determined by many factors such as the work function and the oxygen affinity of the electrode metals. The SET and RESET switching of an individual filament at the surface of a SrTiO3 single crystal shows that the resistance of the filament can be switched between an ONand OFFstate by a voltage applied to the tip of the LC-AFM. The dissolution of cylindric metal filaments studied by electrothermal simulation is described by a thermally activated process of the filament surface.
Conference Paper
Nonvolatile memories (NVMs) based on an instantaneous resistance change when an electric bias is applied are very attractive for future memory applications. Here, we report the fabrication and electrical characterization of mum-sized Cu<sub>2</sub>S NVM devices. With stoichiometric Cu<sub>2</sub>S films grown by anodic polarization, we can generate consistent and reproducible resistance switching devices. The fabricated devices exhibit large on/off ratio over 10<sup>5</sup> with low switching voltages (below 0.3 V). On-resistance (R<sub>on</sub>) value of 150 Omega does not change as the size of the devices shrinks. On the contrary, off-resistance (R<sub>off</sub>) depends on the device area inversely, which enables the enhancement of on/off ratio with the scaling-down of the device.