Enhanced electrical properties of ZrO2-TiN based capacitors by introducing ultrathin metal oxides

•The effect of the ultrathin buffer on electrical properties was investigated.•The electrical properties of ZrO2 films were improved by introducing metal oxide buffers.•The ultrathin Ta2O5 buffer exhibited remarkable improvement in electrical properties.•An EOT scaling of 0.15 nm was achievable with...

Full description

Saved in:
Bibliographic Details
Published in:Materials letters 2020-11, Vol.279, p.128490, Article 128490
Main Authors: Lee, Dong-Kwon, Kim, Hyo-Bae, Kwon, Se-Hun, Ahn, Ji-Hoon
Format: Article
Language:English
Subjects:
Atomic layer deposition
Buffer
Buffers
Capacitors
Dielectric constant
Dielectric properties
DRAM capacitor
Electrical properties
Electrodes
Leakage current
Materials science
Metal oxides
Noble metals
Tantalum
Tantalum oxides
Thin films
Titanium dioxide
Zinc oxide
Zirconium dioxide
ZrO2
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:•The effect of the ultrathin buffer on electrical properties was investigated.•The electrical properties of ZrO2 films were improved by introducing metal oxide buffers.•The ultrathin Ta2O5 buffer exhibited remarkable improvement in electrical properties.•An EOT scaling of 0.15 nm was achievable without introducing new high-k materials. Owing to the scaling down of dynamic random-access-memory, the development of new high-k dielectrics as well as the reduction in the equivalent-oxide-thickness value using ZrO2 and TiN electrode-based capacitors have become crucial. Because the unwanted interfacial layer between ZrO2 and TiN electrodes can induce the degradation of electrical properties, we propose a new approach for improving capacitor properties by introducing ultrathin metal oxides as the buffers. Each ultrathin TiO2, Ta2O5, and ZnO is inserted between ZrO2 thin films and the top or bottom electrodes, and the variations in their electrical properties are investigated. We discovered that the electrical properties of ZrO2-based capacitors, such as the dielectric constant and leakage current density, can be improved by introducing certain types of buffers without requiring a noble metal electrode and higher-k dielectrics. Furthermore, we discovered that the EOT scaling of approximately 0.15 nm is achievable only through the introduction of the appropriate buffer.
ISSN:0167-577X
1873-4979
DOI:10.1016/j.matlet.2020.128490