scholarly journals Demonstration of Threshold Switching and Bipolar Resistive Switching in Ag/SnOx/TiN Memory Device

Metals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1605
Author(s):  
Jooyoung Pyo ◽  
Seungjin Woo ◽  
Kisong Lee ◽  
Sungjun Kim
Keyword(s):  
Resistive Switching ◽  
Photoelectron Spectroscopy ◽  
Pulse Amplitude ◽  
Memory Device ◽  
Gradual Transition ◽  
Bipolar Resistive Switching ◽  
Memory Switching ◽  
Threshold Switching ◽  
Non Volatile Memory ◽  
Multiple Pulses

In this work, we observed the duality of threshold switching and non-volatile memory switching of Ag/SnOx/TiN memory devices by controlling the compliance current (CC) or pulse amplitude. The insulator thickness and chemical analysis of the device stack were confirmed by transmission electron microscope (TEM) images of the Ag/SnOx/TiN stack and X-ray photoelectron spectroscopy (XPS) of the SnOx film. The threshold switching was achieved at low CC (50 μA), showing volatile resistive switching. Optimal CC (5 mA) for bipolar resistive switching conditions with a gradual transition was also found. An unstable low-resistance state (LRS) and negative-set behavior were observed at CCs of 1 mA and 30 mA, respectively. We also demonstrated the pulse operation for volatile switching, set, reset processes, and negative-set behaviors by controlling pulse amplitude and polarity. Finally, the potentiation and depression characteristics were mimicked by multiple pulses, and MNIST pattern recognition was calculated using a neural network, including the conductance update for a hardware-based neuromorphic system.

Eliminating failure behavior by introducing CdS inter-layer in Cu2O-based memory cell

2018 ◽  
Vol 81 (2) ◽  
pp. 20101 ◽  
Author(s):  
Weijie Duan ◽  
Zhenxing Liu ◽  
Yang Zhang
Keyword(s):  
Resistive Switching ◽  
Random Access ◽  
Memory Cell ◽  
Memory Device ◽  
Failure Behavior ◽  
Access Memory ◽  
Bipolar Resistive Switching ◽  
Non Volatile Memory ◽  
Switching Characteristics ◽  
High Set

Resistive switching random access memory (RRAM) has attracted great attention due to its outstanding performance for the next generation non-volatile memory. However, the unexpected failure behaviors seriously hinder the further studies and applications of this new memory device. In this work, the bipolar resistive switching characteristics in Pt/CdS/Cu2O/FTO cells are investigated. The CdS inter-layer is used to suppress the failure behavior in set process. Comparing to the Pt/Cu2O/FTO cell, the switching process in Pt/CdS/Cu2O/FTO cell is not affected even at a high set voltage and the failure behavior is eliminated effectively. Therefore, this work proposes a feasible approach to solve the failure problem in RRAM.

scholarly journals Bipolar and Complementary Resistive Switching Characteristics and Neuromorphic System Simulation in a Pt/ZnO/TiN Synaptic Device

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 315 ◽  
Author(s):  
Sobia Ali Khan ◽  
Geun Ho Lee ◽  
Chandreswar Mahata ◽  
Muhammad Ismail ◽  
Hyungjin Kim ◽  
...  
Keyword(s):  
Resistive Switching ◽  
Photoelectron Spectroscopy ◽  
Recognition Rate ◽  
Long Term Potentiation ◽  
Memory Device ◽  
Chemical Information ◽  
Bipolar Resistive Switching ◽  
Cross Point ◽  
Pulse Input

In this work, a ZnO-based resistive switching memory device is characterized by using simplified electrical conduction models. The conventional bipolar resistive switching and complementary resistive switching modes are accomplished by tuning the bias voltage condition. The material and chemical information of the device stack including the interfacial layer of TiON is well confirmed by transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analysis. The device exhibits uniform gradual bipolar resistive switching (BRS) with good endurance and self-compliance characteristics. Moreover, complementary resistive switching (CRS) is achieved by applying the compliance current at negative bias and increasing the voltage at positive bias. The synaptic behaviors such as long-term potentiation and long-term depression are emulated by applying consecutive pulse input to the device. The CRS mode has a higher array size in the cross-point array structure than the BRS mode due to more nonlinear I–V characteristics in the CRS mode. However, we reveal that the BRS mode shows a better pattern recognition rate than the CRS mode due to more uniform conductance update.

scholarly journals Gradually Modified Conductance in the Self-Compliance Region of an Atomic-Layer-Deposited Pt/TiO2/HfAlOx/TiN RRAM Device

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1199
Author(s):  
Hojeong Ryu ◽  
Sungjun Kim
Keyword(s):  
Photoelectron Spectroscopy ◽  
Depth Profiling ◽  
Atomic Layer ◽  
High Resistance State ◽  
Long Term Potentiation ◽  
Memory Device ◽  
Bipolar Resistive Switching ◽  
Term Potentiation ◽  
Resistance State ◽  
Neuromorphic System

This study presents conductance modulation in a Pt/TiO2/HfAlOx/TiN resistive memory device in the compliance region for neuromorphic system applications. First, the chemical and material characteristics of the atomic-layer-deposited films were verified by X-ray photoelectron spectroscopy depth profiling. The low-resistance state was effectively controlled by the compliance current, and the high-resistance state was adjusted by the reset stop voltage. Stable endurance and retention in bipolar resistive switching were achieved. When a compliance current of 1 mA was imposed, only gradual switching was observed in the reset process. Self-compliance was used after an abrupt set transition to achieve a gradual set process. Finally, 10 cycles of long-term potentiation and depression were obtained in the compliance current region for neuromorphic system applications.

scholarly journals Resistive Switching Characteristics of Li-Doped ZnO Thin Films Based on Magnetron Sputtering

Materials ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1282 ◽  
Author(s):  
Zhao ◽  
Li ◽  
Ai ◽  
Wen
Keyword(s):  
Thin Films ◽  
Magnetron Sputtering ◽  
Resistive Switching ◽  
Photoelectron Spectroscopy ◽  
Lattice Structure ◽  
Zno Thin Films ◽  
Bipolar Resistive Switching ◽  
X Ray ◽  
Doped Zno ◽  
Switching Characteristics

A kind of devices Pt/Ag/ZnO:Li/Pt/Ti with high resistive switching behaviors were prepared on a SiO2/Si substrate by using magnetron sputtering method and mask technology, composed of a bottom electrode (BE) of Pt/Ti, a resistive switching layer of ZnO:Li thin film and a top electrode (TE) of Pt/Ag. To determine the crystal lattice structure and the Li-doped concentration in the resulted ZnO thin films, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) tests were carried out. Resistive switching behaviors of the devices with different thicknesses of Li-doped ZnO thin films were studied at different set and reset voltages based on analog and digital resistive switching characteristics. At room temperature, the fabricated devices represent stable bipolar resistive switching behaviors with a low set voltage, a high switching current ratio and a long retention up to 104 s. In addition, the device can sustain an excellent endurance more than 103 cycles at an applied pulse voltage. The mechanism on how the thicknesses of the Li-doped ZnO thin films affect the resistive switching behaviors was investigated by installing conduction mechanism models. This study provides a new strategy for fabricating the resistive random access memory (ReRAM) device used in practice.

scholarly journals Improved Stability and Controllability in ZrN-Based Resistive Memory Device by Inserting TiO2 Layer

Micromachines ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 905
Author(s):  
Junhyeok Choi ◽  
Sungjun Kim
Keyword(s):  
Data Storage ◽  
Resistive Switching ◽  
Memory Device ◽  
Comparison Study ◽  
Tio2 Layer ◽  
Bipolar Resistive Switching ◽  
Resistive Switching Memory ◽  
Current Voltage ◽  
Improved Stability ◽  
Switching Characteristics

In this work, the enhanced resistive switching of ZrN-based resistive switching memory is demonstrated by embedding TiO2 layer between Ag top electrode and ZrN switching layer. The Ag/ZrN/n-Si device exhibits unstable resistive switching as a result of the uncontrollable Ag migration. Both unipolar and bipolar resistive switching with high RESET current were observed. Negative-SET behavior in the Ag/ZrN/n-Si device makes set-stuck, causing permanent resistive switching failure. On the other hand, the analogue switching in the Ag/TiO2/ZrN/n-Si device, which could be adopted for the multi-bit data storage applications, is obtained. The gradual switching in Ag/TiO2/ZrN/n-Si device is achieved, possibly due to the suppressed Ag diffusion caused by TiO2 inserting layer. The current–voltage (I–V) switching characteristics of Ag/ZrN/n-Si and Ag/TiO2/ZrN/n-Si devices can be well verified by pulse transient. Finally, we established that the Ag/TiO2/ZrN/n-Si device is suitable for neuromorphic application through a comparison study of conductance update. This paper paves the way for neuromorphic application in nitride-based memristor devices.

scholarly journals In Situ Nanostructural Analysis of Volatile Threshold Switching and Non‐Volatile Bipolar Resistive Switching in Mixed‐Phased a ‐VO x Asymmetric Crossbars

2019 ◽  
Vol 5 (12) ◽  
pp. 1900605 ◽  
Author(s):  
Shruti Nirantar ◽  
Edwin Mayes ◽  
Md. Ataur Rahman ◽  
Taimur Ahmed ◽  
Mohammad Taha ◽  
...  
Keyword(s):  
Resistive Switching ◽  
Bipolar Resistive Switching ◽  
Threshold Switching

TEM and EELS Study on TaOx-based Nanoscale Resistive Switching Devices

2015 ◽  
Vol 1805 ◽  
Author(s):  
Kate J. Norris ◽  
J. Joshua Yang ◽  
Nobuhiko P. Kobayashi
Keyword(s):  
Resistive Switching ◽  
Electrical Resistance ◽  
Tantalum Oxide ◽  
Memory Device ◽  
Material System ◽  
Reversible Change ◽  
Cross Sectional ◽  
X Ray ◽  
Non Volatile Memory ◽  
Switching Devices

ABSTRACTResistive switching, a reversible change in electrical resistance of a dielectric layer through the application of a voltage bias, has propelled a field of research to form improved non-volatile memory device. Tantalum oxide has been investigated as the dielectric component of resistive switching devices as a leading candidate for a few years. Presented here is a structural and chemical investigation of TaOx devices with 55nm in diameter in the virgin, forming on, and switched off (reset) states for comparison using cross sectional TEM techniques including HRTEM, and EELS to gain further understanding of this material system. The nanodevices imaged in this study were switched below 100µA. Unique features found in this study are in agreement with previous hypotheses made by various researchers based on X-ray fluorescence microscopy of micron-scale devices, indicating a variation in oxygen concentration around the switching area.

Sign in / Sign up

Export Citation Format

Share Document