Composition, structure, and electrical characteristics of HfO 2 gate dielectrics grown using the remote- and direct-plasma atomic layer deposition methods

Jinwoo Kim, Seokhoon Kim, Hyunseok Kang, Jihoon Choi, Hyeongtag Jeon, Mannho Cho, Kwunbum Chung, Sungkwun Back, Kyungdong Yoo, Choelhwyi Bae

Research output: Contribution to journalArticle

37 Citations (Scopus)

Abstract

Hafnium oxide thin films were deposited using both the remote-plasma atomic layer deposition (RPALD) and direct-plasma atomic layer deposition (DPALD) methods. Metal-oxide semiconductor (MOS) capacitors and transistors were fabricated with Hf O2 gate dielectric to examine their electrical characteristics. The as-deposited RPALD Hf O2 layer exhibited an amorphous structure, while the DPALD Hf O2 layer exhibited a polycrystalline structure. Medium-energy ion scattering measurement data indicate that the interfacial layer consisted of interfacial Si O2-x and silicate layers. This suggests that the change in stoichiometry with depth could be related to the energetic plasma beam used in the plasma ALD process, resulting in damage to the Si surface and an interaction between Hf and Si O2-x. The as-deposited RPALD Hf O2 films had better interfacial layer characteristics, such as an effective fixed oxide charge density (Qf,eff) and interfacial roughness than the DPALD Hf O2 films did. A MOS capacitor fabricated using the RPALD method exhibited an equivalent oxide thickness (EOT) of 1.8 nm with a Qf,eff =-4.2× 1011 q cm2 (where q is the elementary charge, 1.6022× 10-19 C), whereas a MOS capacitor fabricated using the DPALD method had an EOT=2.0 nm and a Qf,eff =-1.2× 1013 q cm2. At a power=0.6 MVcm, the RPALD n -type metal-oxide semiconductor field-effect transistor (nMOSFET) showed μeff =168 cm2 V s, which was 50% greater than the value of the DPALD nMOSFET (μeff =111 cm2 V s). In the region where Vg - Vt =2.0 V, the RPALD MOSFET drain current was about 30% higher than the DPALD MOSFET drain current. These improvements are believed to be due to the lower effective fixed charge density, and they minimize problems arising from plasma charging damage.

Original languageEnglish
Article number094504
JournalJournal of Applied Physics
Volume98
Issue number9
DOIs
Publication statusPublished - 2005 Nov 1

Fingerprint

atomic layer epitaxy
metal oxide semiconductors
field effect transistors
capacitors
n-type semiconductors
oxides
damage
hafnium oxides
ion scattering
surface reactions
charging
stoichiometry
silicates
transistors
roughness

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Cite this

Kim, Jinwoo ; Kim, Seokhoon ; Kang, Hyunseok ; Choi, Jihoon ; Jeon, Hyeongtag ; Cho, Mannho ; Chung, Kwunbum ; Back, Sungkwun ; Yoo, Kyungdong ; Bae, Choelhwyi. / Composition, structure, and electrical characteristics of HfO 2 gate dielectrics grown using the remote- and direct-plasma atomic layer deposition methods. In: Journal of Applied Physics. 2005 ; Vol. 98, No. 9.
@article{0f30b7bc8d974577b664a915bd1a01cc,
title = "Composition, structure, and electrical characteristics of HfO 2 gate dielectrics grown using the remote- and direct-plasma atomic layer deposition methods",
abstract = "Hafnium oxide thin films were deposited using both the remote-plasma atomic layer deposition (RPALD) and direct-plasma atomic layer deposition (DPALD) methods. Metal-oxide semiconductor (MOS) capacitors and transistors were fabricated with Hf O2 gate dielectric to examine their electrical characteristics. The as-deposited RPALD Hf O2 layer exhibited an amorphous structure, while the DPALD Hf O2 layer exhibited a polycrystalline structure. Medium-energy ion scattering measurement data indicate that the interfacial layer consisted of interfacial Si O2-x and silicate layers. This suggests that the change in stoichiometry with depth could be related to the energetic plasma beam used in the plasma ALD process, resulting in damage to the Si surface and an interaction between Hf and Si O2-x. The as-deposited RPALD Hf O2 films had better interfacial layer characteristics, such as an effective fixed oxide charge density (Qf,eff) and interfacial roughness than the DPALD Hf O2 films did. A MOS capacitor fabricated using the RPALD method exhibited an equivalent oxide thickness (EOT) of 1.8 nm with a Qf,eff =-4.2× 1011 q cm2 (where q is the elementary charge, 1.6022× 10-19 C), whereas a MOS capacitor fabricated using the DPALD method had an EOT=2.0 nm and a Qf,eff =-1.2× 1013 q cm2. At a power=0.6 MVcm, the RPALD n -type metal-oxide semiconductor field-effect transistor (nMOSFET) showed μeff =168 cm2 V s, which was 50{\%} greater than the value of the DPALD nMOSFET (μeff =111 cm2 V s). In the region where Vg - Vt =2.0 V, the RPALD MOSFET drain current was about 30{\%} higher than the DPALD MOSFET drain current. These improvements are believed to be due to the lower effective fixed charge density, and they minimize problems arising from plasma charging damage.",
author = "Jinwoo Kim and Seokhoon Kim and Hyunseok Kang and Jihoon Choi and Hyeongtag Jeon and Mannho Cho and Kwunbum Chung and Sungkwun Back and Kyungdong Yoo and Choelhwyi Bae",
year = "2005",
month = "11",
day = "1",
doi = "10.1063/1.2121929",
language = "English",
volume = "98",
journal = "Journal of Applied Physics",
issn = "0021-8979",
publisher = "American Institute of Physics Publising LLC",
number = "9",

}

Composition, structure, and electrical characteristics of HfO 2 gate dielectrics grown using the remote- and direct-plasma atomic layer deposition methods. / Kim, Jinwoo; Kim, Seokhoon; Kang, Hyunseok; Choi, Jihoon; Jeon, Hyeongtag; Cho, Mannho; Chung, Kwunbum; Back, Sungkwun; Yoo, Kyungdong; Bae, Choelhwyi.

In: Journal of Applied Physics, Vol. 98, No. 9, 094504, 01.11.2005.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Composition, structure, and electrical characteristics of HfO 2 gate dielectrics grown using the remote- and direct-plasma atomic layer deposition methods

AU - Kim, Jinwoo

AU - Kim, Seokhoon

AU - Kang, Hyunseok

AU - Choi, Jihoon

AU - Jeon, Hyeongtag

AU - Cho, Mannho

AU - Chung, Kwunbum

AU - Back, Sungkwun

AU - Yoo, Kyungdong

AU - Bae, Choelhwyi

PY - 2005/11/1

Y1 - 2005/11/1

N2 - Hafnium oxide thin films were deposited using both the remote-plasma atomic layer deposition (RPALD) and direct-plasma atomic layer deposition (DPALD) methods. Metal-oxide semiconductor (MOS) capacitors and transistors were fabricated with Hf O2 gate dielectric to examine their electrical characteristics. The as-deposited RPALD Hf O2 layer exhibited an amorphous structure, while the DPALD Hf O2 layer exhibited a polycrystalline structure. Medium-energy ion scattering measurement data indicate that the interfacial layer consisted of interfacial Si O2-x and silicate layers. This suggests that the change in stoichiometry with depth could be related to the energetic plasma beam used in the plasma ALD process, resulting in damage to the Si surface and an interaction between Hf and Si O2-x. The as-deposited RPALD Hf O2 films had better interfacial layer characteristics, such as an effective fixed oxide charge density (Qf,eff) and interfacial roughness than the DPALD Hf O2 films did. A MOS capacitor fabricated using the RPALD method exhibited an equivalent oxide thickness (EOT) of 1.8 nm with a Qf,eff =-4.2× 1011 q cm2 (where q is the elementary charge, 1.6022× 10-19 C), whereas a MOS capacitor fabricated using the DPALD method had an EOT=2.0 nm and a Qf,eff =-1.2× 1013 q cm2. At a power=0.6 MVcm, the RPALD n -type metal-oxide semiconductor field-effect transistor (nMOSFET) showed μeff =168 cm2 V s, which was 50% greater than the value of the DPALD nMOSFET (μeff =111 cm2 V s). In the region where Vg - Vt =2.0 V, the RPALD MOSFET drain current was about 30% higher than the DPALD MOSFET drain current. These improvements are believed to be due to the lower effective fixed charge density, and they minimize problems arising from plasma charging damage.

AB - Hafnium oxide thin films were deposited using both the remote-plasma atomic layer deposition (RPALD) and direct-plasma atomic layer deposition (DPALD) methods. Metal-oxide semiconductor (MOS) capacitors and transistors were fabricated with Hf O2 gate dielectric to examine their electrical characteristics. The as-deposited RPALD Hf O2 layer exhibited an amorphous structure, while the DPALD Hf O2 layer exhibited a polycrystalline structure. Medium-energy ion scattering measurement data indicate that the interfacial layer consisted of interfacial Si O2-x and silicate layers. This suggests that the change in stoichiometry with depth could be related to the energetic plasma beam used in the plasma ALD process, resulting in damage to the Si surface and an interaction between Hf and Si O2-x. The as-deposited RPALD Hf O2 films had better interfacial layer characteristics, such as an effective fixed oxide charge density (Qf,eff) and interfacial roughness than the DPALD Hf O2 films did. A MOS capacitor fabricated using the RPALD method exhibited an equivalent oxide thickness (EOT) of 1.8 nm with a Qf,eff =-4.2× 1011 q cm2 (where q is the elementary charge, 1.6022× 10-19 C), whereas a MOS capacitor fabricated using the DPALD method had an EOT=2.0 nm and a Qf,eff =-1.2× 1013 q cm2. At a power=0.6 MVcm, the RPALD n -type metal-oxide semiconductor field-effect transistor (nMOSFET) showed μeff =168 cm2 V s, which was 50% greater than the value of the DPALD nMOSFET (μeff =111 cm2 V s). In the region where Vg - Vt =2.0 V, the RPALD MOSFET drain current was about 30% higher than the DPALD MOSFET drain current. These improvements are believed to be due to the lower effective fixed charge density, and they minimize problems arising from plasma charging damage.

UR - http://www.scopus.com/inward/record.url?scp=27844573485&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=27844573485&partnerID=8YFLogxK

U2 - 10.1063/1.2121929

DO - 10.1063/1.2121929

M3 - Article

AN - SCOPUS:27844573485

VL - 98

JO - Journal of Applied Physics

JF - Journal of Applied Physics

SN - 0021-8979

IS - 9

M1 - 094504

ER -