Multilevel programming in Cu/NiO_y/NiO_x/Pt unipolar resistive switching devices

Abstract

The application of a NiO y /NiO x bilayer in resistive switching (RS) devices with x > y was studied for its ability to achieve reliable multilevel cell (MLC) characteristics. A sharp change in resistance brought about by sweeping the voltage, along with an improved on/off ratio (>10(3)) and endurance (10(4)) were achieved in the bilayer structure as compared to the single NiO x layer devices. Moreover, it was found that nonvolatile and stable resistance levels, especially the multiple low-resistance states of Cu/NiO y /NiO x /Pt memory devices, could be controlled by varying the compliance current. All the multilevel resistance states of the Cu/NiO y /NiO x /Pt bilayer devices were stable for up to 500 consecutive dc switching cycles, as compared to the Cu/NiO x /Pt single layer devices. The temperature-dependent variation of the high and low resistance states of both the bilayer and single layer devices was further investigated to elucidate the charge conduction mechanism. Finally, based on a detailed analysis of the experimental results, comparisons of the possible models for RS in bilayer and single layer memory devices have also been discussed.

Cross-Point Resistive Switching Memory and Urea Sensing by Using Annealed GdOxFilm in IrOx/GdOx/W Structure for Biomedical Applications

“…The current increases with increasing CC, which is owing to larger conducting filament diameter resulting lower LRS value. 32 The memory device shows stable multilevel data retention of > 15 hrs at different CCs (Figure 4c) , the resistance ratios are found to be 18, 1200, 2800, and 12400 for CCs of 10, 50, 100, and 300 μA, respectively. In addition, it is an essential requirement to suppress sneak path effect for complementary cross-point array application.…”

Multilevel non‐volatile memory based on Al2O3/ZnO bilayer device

“…Although there is difference in the material selection for CBRAM and VCM, the basic characteristics shown by both can be either unipolar resistive switching (URS) [10, 11] or bipolar resistive switching (BRS) with exception of its switching polarity. Both URS and BRS exhibit two stable resistance states, namely high resistance state (HRS) and low resistance state (LRS), whereas several other devices exhibit stable intermediate resistance states (IRS) in addition to LRS and HRS, capable of storing multiple bits known as multilevel‐cell (MLC) which is the widely recognised solution to attain ultra‐high‐density memories [12, 13] with 4F 2 memory cell, where F is the minimum feature size. MLC is becoming an emerging field as it has applications in neuromorphic computing, look up table (LUT) implementation in field programmable gate arrays (FPGA) and so on.…”

Highly Uniform Resistive Switching Properties of Solution‐Processed Silver‐Embedded Gelatin Thin Film

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the nonuniformity of resistive switching parameters. [7][8][9][10][11][12] Recently, most organic memory devices used metallic nanoparticles blended into an organic host to improve their memory properties. [13][14][15][16] Organic nanocomposites, by dispersing metal nanoparticles in organic matrixes, always possess greatly enhanced mechanical, optical, and electrical properties, and so on.

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“…In our previous study, the gelatin memory devices show good stability under atmosphere and the conduction behavior of gelatin memory devices was governed by the formation of filaments. However, the filamentary switching of memory device in general exhibits a natural fluctuation, which leads to the nonuniformity of resistive switching parameters . Recently, most organic memory devices used metallic nanoparticles blended into an organic host to improve their memory properties .…”