Interface Modification of Bernal- and Rhombohedral-Stacked Trilayer-Graphene/Metal Electrode on Resistive Switching of Silver Electrochemical Metallization Cells

Abstract

Bernal- and rhombohedral-stacked trilayer graphene (B- and r-TLG) on nickel (Ni) and iridium (Ir) films acting as bottom electrodes (BEs) of silver electrochemical metallization cells (Ag-EMCs) have been investigated in this study. Prior to the fabrication of the EMC devices, Raman mapping and atomic force microscopy are applied to identify the B- and r-TLG sheets, with the latter revealing a significant D peak and a rough surface for the Ir film. The Ag-EMCs with the stacked BE of r-TLG on the Ir film show a conductive mechanism of Schottky emission at the positive top electrode bias for both high- and low-resistance states that can be examined by the resistance change with the device area and are modulated by pulse bias operation. Thus, an effective electron barrier height of 0.262 eV at the r-TLG and Ir interface is obtained because of the conspicuous energy gap of r-TLG on the Ir film and the van der Waals (vdW) gap between the r-TLG and Ir contact metal. With the use of Ni instead of Ir contact metal, the Ag-EMCs with TLG BE demonstrate +0.3 V/-0.75 V operation voltages, more than 10 s data retention at 115 °C and 250 times endurance testing, making the TLG sheets suitable for low-power nonvolatile memory applications on flexible substrates.

Multilevel resistive switching behaviors of N2-plasma-treated stacked GdO x /SiN x RRAMs

“…8(a). The fitting result can be attributed to the barrier height between the Ir TE and GdO x RS layers, which can be extracted as 0.71 eV; however, the barrier height is smaller than the value reported, 30) the reason for which may be because the thickness of the GdO x film is only 12 nm. In the MRS1 and MRS2 regions, with the I-V relationship re-plotted as the current density versus the square of the applied voltage (J-V 2 ), the conductive mechanism of the SCLC is able to be confirmed based on the linear fitting presented in Figs.…”