Cubic-phase zirconia nano-island growth using atomic layer deposition and application in low-power charge-trapping nonvolatile-memory devices
Author(s)
Date
2017Source Title
Nanotechnology
Print ISSN
0957-4484
Electronic ISSN
1361-6528
Publisher
Institute of Physics Publishing Ltd.
Volume
28
Issue
44
Language
English
Type
ArticleItem Usage Stats
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Abstract
The manipulation of matter at the nanoscale enables the generation of properties in a material that would otherwise be challenging or impossible to realize in the bulk state. Here, we demonstrate growth of zirconia nano-islands using atomic layer deposition on different substrate terminations. Transmission electron microscopy and Raman measurements indicate that the nano-islands consist of nano-crystallites of the cubic-crystalline phase, which results in a higher dielectric constant (κ ∼ 35) than the amorphous phase case (κ ∼ 20). X-ray photoelectron spectroscopy measurements show that a deep quantum well is formed in the Al2O3/ZrO2/Al2O3 system, which is substantially different to that in the bulk state of zirconia and is more favorable for memory application. Finally, a memory device with a ZrO2 nano-island charge-trapping layer is fabricated, and a wide memory window of 4.5 V is obtained at a low programming voltage of 5 V due to the large dielectric constant of the islands in addition to excellent endurance and retention characteristics.
Keywords
Atomic layer depositionMemory devices
Zirconia
Atomic layer deposition
Atoms
Charge trapping
Data storage equipment
Deposition
High resolution transmission electron microscopy
Nonvolatile storage
Quantum theory
Semiconductor quantum wells
Transmission electron microscopy
Zirconia
Zirconium compounds
Charge trapping layers
Different substrates
Large dielectric constant
Memory applications
Nonvolatile memory devices
Programming voltage
Raman measurements
Retention characteristics
X ray photoelectron spectroscopy