Enhanced switching ratio of sol–gel-processed Y₂O₃ RRAM device by suppressing oxygen vacancy formation at high annealing temperatures

Abstract

Sol–gel-processed Y2O3 films were used as an active-channel layer for RRAM devices. The effect of post-annealing temperature on structural, chemical, and electrical characteristics was investigated. The Y2O3-RRAM devices, comprising electrochemically active metal electrodes, Ag, and Indium tin oxide (ITO) electrodes exhibited the conventional bipolar RRAM device operation. The fabricated Ag/Y2O3/ITO RRAM devices, comprising 500-℃ annealed Y2O3 films, exhibited less oxygen vacancy and defect, which reduced the leakage current and boosted high-resistance state/low-resistance state ratio, more than 10^5, and promising nonvolatile memory properties without deterioration for 100 cycles and 10^4 seconds.

Enhanced Switching Reliability of Sol–Gel-Processed Y2O3 RRAM Devices Based on Y2O3 Surface Roughness-Induced Local Electric Field

“…Several Y 2 O 3 -based RRAM devices have shown that the resistive switching memory behavior can be attributed to the formation and destruction of an O v –based conductive path. ITO/Y 2 O 3 /Au RRAM devices do not show these characteristics of RRAM devices [ 14 ], indicating that the formation and rupture of the metallic conductive path, originating from the oxidation and reduction processes from Ag electrodes, are the main mechanisms of ITO/Y 2 O 3 /Ag RRAM devices. The fabricated devices showed a high-resistance state (HRS).…”

“…Furthermore, Y 2 O 3 has emerged as a promising active material for preparing RRAM devices [ 10 , 11 , 12 ]. Forming-free RRAM devices can be prepared using oxygen vacancy (O v )–rich Y 2 O 3 [ 13 , 14 ]. The forming process requires an additional large voltage for the initial conductive filament (CF), occasionally resulting in electrode destruction.…”

Flexible Sol-Gel—Processed Y2O3 RRAM Devices Obtained via UV/Ozone-Assisted Photochemical Annealing Process

“…In this system, the deposited top Ag electrode served as the main source for the formation of a conductive path between the top and bottom ITO electrodes. Our previous study demonstrated that using inert top Au electrodes, the fabricated device showed no resistive switching memory properties, indicating that the fabricated RRAM device was a type of ECM RRAM [ 11 ]. The initial resistance status was a high-resistance status (HRS).…”

“…For this imitation, memory devices with high density, high performance, and low-power operation are required. Several metal–oxide active channel materials, such as SiO x , ZrO 2 , TiO x , Hf x O, and Y 2 O 3 , have been considered for RRAM device fabrication [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 ]. Y 2 O 3 is characterized by a high dielectric constant, large optical bandgap, and fast internal ion transport and is therefore considered quite attractive for use in such devices.…”

Improved Environment Stability of Y2O3 RRAM Devices with Au Passivated Ag Top Electrodes

“…Recently, to realize a neuromorphic computing system that mimics the human brain, RRAMs have been used because of the aforementioned advantages. Many metal oxides such as SiO x , ZrO 2 , TiO x , Hf x O, and Y 2 O 3 have been studied for use in RRAM devices [ 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. Among these, Y 2 O 3 demonstrates advantages over other metal oxides.…”