Evolution of ferroelectric HfO2 in ultrathin region down to 3 nm

Xuan Tian; Shigehisa Shibayama; Tomonori Nishimura; Takeaki Yajima; Shinji Migita; Akira Toriumi

doi:10.1063/1.5017094

Evolution of ferroelectric HfO₂ in ultrathin region down to 3 nm

Xuan Tian, Shigehisa Shibayama, Tomonori Nishimura, Takeaki Yajima, Shinji Migita, Akira Toriumi

Research output: Contribution to journal › Article › peer-review

209 Citations (Scopus)

Abstract

The ferroelectric properties of ultrathin Y-doped HfO₂ films were investigated. Ferroelectricity was demonstrated experimentally in 3 nm-thick Y-doped HfO₂ via direct detection of displacement currents during polarization switching. The dependence on the HfO₂ thickness within the 30 to 3 nm range revealed that the ferroelectric properties decrease rapidly below a critical thickness. In the ultrathin HfO₂ region, methods such as higher Y doping or metal capping annealing were required to further stabilize the ferroelectric phase. These methods could be used to enhance the switchable polarization (P_sw) to 35 μC/cm² in 5 nm- and 10 μC/cm² in 3 nm-thick Y-doped HfO₂. This paper indicates that HfO₂ ferroelectricity is scalable even in the ultrathin region.

Original language	English
Article number	102902
Journal	Applied Physics Letters
Volume	112
Issue number	10
DOIs	https://doi.org/10.1063/1.5017094
Publication status	Published - Mar 5 2018
Externally published	Yes

All Science Journal Classification (ASJC) codes

Physics and Astronomy (miscellaneous)

Access to Document

10.1063/1.5017094

Cite this

@article{7b671b9548ac45bd9302c50028e01237,

title = "Evolution of ferroelectric HfO2 in ultrathin region down to 3 nm",

abstract = "The ferroelectric properties of ultrathin Y-doped HfO2 films were investigated. Ferroelectricity was demonstrated experimentally in 3 nm-thick Y-doped HfO2 via direct detection of displacement currents during polarization switching. The dependence on the HfO2 thickness within the 30 to 3 nm range revealed that the ferroelectric properties decrease rapidly below a critical thickness. In the ultrathin HfO2 region, methods such as higher Y doping or metal capping annealing were required to further stabilize the ferroelectric phase. These methods could be used to enhance the switchable polarization (Psw) to 35 μC/cm2 in 5 nm- and 10 μC/cm2 in 3 nm-thick Y-doped HfO2. This paper indicates that HfO2 ferroelectricity is scalable even in the ultrathin region.",

author = "Xuan Tian and Shigehisa Shibayama and Tomonori Nishimura and Takeaki Yajima and Shinji Migita and Akira Toriumi",

note = "Publisher Copyright: {\textcopyright} 2018 Author(s).",

year = "2018",

month = mar,

day = "5",

doi = "10.1063/1.5017094",

language = "English",

volume = "112",

journal = "Applied Physics Letters",

issn = "0003-6951",

publisher = "American Institute of Physics",

number = "10",

}

TY - JOUR

T1 - Evolution of ferroelectric HfO2 in ultrathin region down to 3 nm

AU - Tian, Xuan

AU - Shibayama, Shigehisa

AU - Nishimura, Tomonori

AU - Yajima, Takeaki

AU - Migita, Shinji

AU - Toriumi, Akira

PY - 2018/3/5

Y1 - 2018/3/5

N2 - The ferroelectric properties of ultrathin Y-doped HfO2 films were investigated. Ferroelectricity was demonstrated experimentally in 3 nm-thick Y-doped HfO2 via direct detection of displacement currents during polarization switching. The dependence on the HfO2 thickness within the 30 to 3 nm range revealed that the ferroelectric properties decrease rapidly below a critical thickness. In the ultrathin HfO2 region, methods such as higher Y doping or metal capping annealing were required to further stabilize the ferroelectric phase. These methods could be used to enhance the switchable polarization (Psw) to 35 μC/cm2 in 5 nm- and 10 μC/cm2 in 3 nm-thick Y-doped HfO2. This paper indicates that HfO2 ferroelectricity is scalable even in the ultrathin region.

AB - The ferroelectric properties of ultrathin Y-doped HfO2 films were investigated. Ferroelectricity was demonstrated experimentally in 3 nm-thick Y-doped HfO2 via direct detection of displacement currents during polarization switching. The dependence on the HfO2 thickness within the 30 to 3 nm range revealed that the ferroelectric properties decrease rapidly below a critical thickness. In the ultrathin HfO2 region, methods such as higher Y doping or metal capping annealing were required to further stabilize the ferroelectric phase. These methods could be used to enhance the switchable polarization (Psw) to 35 μC/cm2 in 5 nm- and 10 μC/cm2 in 3 nm-thick Y-doped HfO2. This paper indicates that HfO2 ferroelectricity is scalable even in the ultrathin region.

UR - http://www.scopus.com/inward/record.url?scp=85043352194&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85043352194&partnerID=8YFLogxK

U2 - 10.1063/1.5017094

DO - 10.1063/1.5017094

M3 - Article

AN - SCOPUS:85043352194

SN - 0003-6951

VL - 112

JO - Applied Physics Letters

JF - Applied Physics Letters

IS - 10

M1 - 102902

ER -

Evolution of ferroelectric HfO₂ in ultrathin region down to 3 nm

Abstract

All Science Journal Classification (ASJC) codes

Access to Document

Other files and links

Fingerprint

Cite this