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Title: Enhancing metal-insulator-insulator-metal tunnel diodes via defect enhanced direct tunneling

Abstract

Metal-insulator-insulator-metal tunnel diodes with dissimilar work function electrodes and nanolaminate Al{sub 2}O{sub 3}-Ta{sub 2}O{sub 5} bilayer tunnel barriers deposited by atomic layer deposition are investigated. This combination of high and low electron affinity insulators, each with different dominant conduction mechanisms (tunneling and Frenkel-Poole emission), results in improved low voltage asymmetry and non-linearity of current versus voltage behavior. These improvements are due to defect enhanced direct tunneling in which electrons transport across the Ta{sub 2}O{sub 5} via defect based conduction before tunneling directly through the Al{sub 2}O{sub 3}, effectively narrowing the tunnel barrier. Conduction through the device is dominated by tunneling, and operation is relatively insensitive to temperature.

Authors:
;  [1]
  1. School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331 (United States)
Publication Date:
OSTI Identifier:
22310962
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM OXIDES; ASYMMETRY; DEFECTS; DIFFUSION BARRIERS; ELECTRIC POTENTIAL; ELECTRODES; EMISSION; EQUIPMENT; LAYERS; METALS; TANTALUM OXIDES; TUNNEL DIODES; TUNNEL EFFECT; WORK FUNCTIONS

Citation Formats

Alimardani, Nasir, and Conley, John F., E-mail: jconley@eecs.oregonstate.edu. Enhancing metal-insulator-insulator-metal tunnel diodes via defect enhanced direct tunneling. United States: N. p., 2014. Web. doi:10.1063/1.4893735.
Alimardani, Nasir, & Conley, John F., E-mail: jconley@eecs.oregonstate.edu. Enhancing metal-insulator-insulator-metal tunnel diodes via defect enhanced direct tunneling. United States. doi:10.1063/1.4893735.
Alimardani, Nasir, and Conley, John F., E-mail: jconley@eecs.oregonstate.edu. Mon . "Enhancing metal-insulator-insulator-metal tunnel diodes via defect enhanced direct tunneling". United States. doi:10.1063/1.4893735.
@article{osti_22310962,
title = {Enhancing metal-insulator-insulator-metal tunnel diodes via defect enhanced direct tunneling},
author = {Alimardani, Nasir and Conley, John F., E-mail: jconley@eecs.oregonstate.edu},
abstractNote = {Metal-insulator-insulator-metal tunnel diodes with dissimilar work function electrodes and nanolaminate Al{sub 2}O{sub 3}-Ta{sub 2}O{sub 5} bilayer tunnel barriers deposited by atomic layer deposition are investigated. This combination of high and low electron affinity insulators, each with different dominant conduction mechanisms (tunneling and Frenkel-Poole emission), results in improved low voltage asymmetry and non-linearity of current versus voltage behavior. These improvements are due to defect enhanced direct tunneling in which electrons transport across the Ta{sub 2}O{sub 5} via defect based conduction before tunneling directly through the Al{sub 2}O{sub 3}, effectively narrowing the tunnel barrier. Conduction through the device is dominated by tunneling, and operation is relatively insensitive to temperature.},
doi = {10.1063/1.4893735},
journal = {Applied Physics Letters},
number = 8,
volume = 105,
place = {United States},
year = {Mon Aug 25 00:00:00 EDT 2014},
month = {Mon Aug 25 00:00:00 EDT 2014}
}
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