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Title: Sub-10 nm Ta Channel Responsible for Superior Performance of a HfO 2 Memristor

Abstract

Memristive devices are promising candidates for the next generation non-volatile memory and neuromorphic computing. It has been widely accepted that the motion of oxygen anions leads to the resistance changes for valence-change-memory (VCM) type of materials. Only very recently it was speculated that metal cations could also play an important role, but no direct physical characterizations have been reported yet. We report a Ta/HfO 2/Pt memristor with fast switching speed, record high endurance (120 billion cycles) and reliable retention. We also programmed the device to 24 discrete resistance levels, and also demonstrated over a million (220) epochs of potentiation and depression, suggesting that our devices can be used for both multi-level non-volatile memory and neuromorphic computing applications. More importantly, we directly observed a sub-10 nm Ta-rich and O-deficient conduction channel within the HfO 2 layer that is responsible for the switching. Our work deepens our understanding of the resistance switching mechanism behind oxide-based memristive devices and paves the way for further device performance optimization for a broad spectrum of applications.

Authors:
 [1];  [2];  [1];  [3];  [3];  [4];  [4];  [3];  [5];  [1]
  1. Univ. of Massachusetts, Amherst, MA (United States). Dept. of Electrical and Computer Engineering
  2. Univ. of Massachusetts, Amherst, MA (United States). Dept. of Electrical and Computer Engineering; Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials
  3. Univ. of Massachusetts, Amherst, MA (United States). Dept. of Electrical and Computer Engineering, Ionic and Electronic Device and Materials Lab.
  4. Information Directorate, Rome, NY (United States). Air Force Research Lab.
  5. Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1336120
Report Number(s):
BNL-112580-2016-JA
Journal ID: ISSN 2045-2322; R&D Project: 16060; 16060; KC0403020
Grant/Contract Number:
SC00112704
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 6; Journal ID: ISSN 2045-2322
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Nonvolatile memeory

Citation Formats

Jiang, Hao, Han, Lili, Lin, Peng, Wang, Zhongrui, Jang, Moon Hyung, Wu, Qing, Barnell, Mark, Yang, J. Joshua, Xin, Huolin L., and Xia, Qiangfei. Sub-10 nm Ta Channel Responsible for Superior Performance of a HfO2 Memristor. United States: N. p., 2016. Web. doi:10.1038/srep28525.
Jiang, Hao, Han, Lili, Lin, Peng, Wang, Zhongrui, Jang, Moon Hyung, Wu, Qing, Barnell, Mark, Yang, J. Joshua, Xin, Huolin L., & Xia, Qiangfei. Sub-10 nm Ta Channel Responsible for Superior Performance of a HfO2 Memristor. United States. doi:10.1038/srep28525.
Jiang, Hao, Han, Lili, Lin, Peng, Wang, Zhongrui, Jang, Moon Hyung, Wu, Qing, Barnell, Mark, Yang, J. Joshua, Xin, Huolin L., and Xia, Qiangfei. 2016. "Sub-10 nm Ta Channel Responsible for Superior Performance of a HfO2 Memristor". United States. doi:10.1038/srep28525. https://www.osti.gov/servlets/purl/1336120.
@article{osti_1336120,
title = {Sub-10 nm Ta Channel Responsible for Superior Performance of a HfO2 Memristor},
author = {Jiang, Hao and Han, Lili and Lin, Peng and Wang, Zhongrui and Jang, Moon Hyung and Wu, Qing and Barnell, Mark and Yang, J. Joshua and Xin, Huolin L. and Xia, Qiangfei},
abstractNote = {Memristive devices are promising candidates for the next generation non-volatile memory and neuromorphic computing. It has been widely accepted that the motion of oxygen anions leads to the resistance changes for valence-change-memory (VCM) type of materials. Only very recently it was speculated that metal cations could also play an important role, but no direct physical characterizations have been reported yet. We report a Ta/HfO2/Pt memristor with fast switching speed, record high endurance (120 billion cycles) and reliable retention. We also programmed the device to 24 discrete resistance levels, and also demonstrated over a million (220) epochs of potentiation and depression, suggesting that our devices can be used for both multi-level non-volatile memory and neuromorphic computing applications. More importantly, we directly observed a sub-10 nm Ta-rich and O-deficient conduction channel within the HfO2 layer that is responsible for the switching. Our work deepens our understanding of the resistance switching mechanism behind oxide-based memristive devices and paves the way for further device performance optimization for a broad spectrum of applications.},
doi = {10.1038/srep28525},
journal = {Scientific Reports},
number = ,
volume = 6,
place = {United States},
year = 2016,
month = 6
}

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