A comparative X-ray photoelectron spectroscopy and medium-energy ion-scattering study of ultra-thin, Hf-based high-k films

L. Sygellou, S. Ladas, M. A. Reading, J. A. Van Den Berg, T. Conard, S. De Gendt

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Ultra-thin high-k layers based on HfO2, or Hf-silicates in combination with sub-nanometer SiO2, show muchpromise in their use as Si-compatible gate dielectrics. XPS has been applied on a range of HfO2/SiO2and HfSiOx(60%Hf)/SiO2films on Si(100), before and after decoupled plasma nitridation (DPN) at 1073 K. The treatment of the data was optimized in order to determine individual layer thicknesses of the multilayer stack taking into account the measured nitrogen content of the nitrided films. The procedure adhered to the prescriptions of ISO18118:2004(E) for the calculations of inelastic mean free paths (IMFP) and elastic corrections thereof, using film material properties, like densities and band gaps. Effective attenuation lengths (EAL) were taken throughout as 90% of the respective IMFP, whereas an appropriate set of empirical relative sensitivity factors (RSF) was used. The XPS-derived thicknesses were compared with corresponding values obtained from medium-energy ion scattering (MEIS) measurements on the same series of specimens in combination with energy spectrum simulation to provide quantitative layer information with sub-nanometer resolution. The XPS and MEIS results exhibit very good agreement on the deduced layer structures within the respective experimental uncertainty, and both sets are consistent with the grown nominal layer parameters of the high-k nanofilms. 
LanguageEnglish
Pages1057-1060
Number of pages4
JournalSurface and Interface Analysis
Volume42
Issue number6-7
Early online date29 Mar 2010
DOIs
Publication statusPublished - Jun 2010
Externally publishedYes

Fingerprint

ion scattering
X ray photoelectron spectroscopy
photoelectron spectroscopy
Scattering
Ions
Silicates
x rays
Nitridation
mean free path
Gate dielectrics
energy
Materials properties
Multilayers
Energy gap
Nitrogen
Plasmas
silicates
energy spectra
attenuation
nitrogen

Cite this

Sygellou, L. ; Ladas, S. ; Reading, M. A. ; Van Den Berg, J. A. ; Conard, T. ; De Gendt, S. / A comparative X-ray photoelectron spectroscopy and medium-energy ion-scattering study of ultra-thin, Hf-based high-k films. In: Surface and Interface Analysis. 2010 ; Vol. 42, No. 6-7. pp. 1057-1060.
@article{920467226fa0413d829cc0a54ec3ead3,
title = "A comparative X-ray photoelectron spectroscopy and medium-energy ion-scattering study of ultra-thin, Hf-based high-k films",
abstract = "Ultra-thin high-k layers based on HfO2, or Hf-silicates in combination with sub-nanometer SiO2, show muchpromise in their use as Si-compatible gate dielectrics. XPS has been applied on a range of HfO2/SiO2and HfSiOx(60{\%}Hf)/SiO2films on Si(100), before and after decoupled plasma nitridation (DPN) at 1073 K. The treatment of the data was optimized in order to determine individual layer thicknesses of the multilayer stack taking into account the measured nitrogen content of the nitrided films. The procedure adhered to the prescriptions of ISO18118:2004(E) for the calculations of inelastic mean free paths (IMFP) and elastic corrections thereof, using film material properties, like densities and band gaps. Effective attenuation lengths (EAL) were taken throughout as 90{\%} of the respective IMFP, whereas an appropriate set of empirical relative sensitivity factors (RSF) was used. The XPS-derived thicknesses were compared with corresponding values obtained from medium-energy ion scattering (MEIS) measurements on the same series of specimens in combination with energy spectrum simulation to provide quantitative layer information with sub-nanometer resolution. The XPS and MEIS results exhibit very good agreement on the deduced layer structures within the respective experimental uncertainty, and both sets are consistent with the grown nominal layer parameters of the high-k nanofilms. ",
keywords = "Hafnium silicate, HfO 2, High-k nanofilms, Layerthickness measurement, MEIS, XPS",
author = "L. Sygellou and S. Ladas and Reading, {M. A.} and {Van Den Berg}, {J. A.} and T. Conard and {De Gendt}, S.",
year = "2010",
month = "6",
doi = "10.1002/sia.3251",
language = "English",
volume = "42",
pages = "1057--1060",
journal = "Surface and Interface Analysis",
issn = "0142-2421",
publisher = "John Wiley and Sons Ltd",
number = "6-7",

}

A comparative X-ray photoelectron spectroscopy and medium-energy ion-scattering study of ultra-thin, Hf-based high-k films. / Sygellou, L.; Ladas, S.; Reading, M. A.; Van Den Berg, J. A.; Conard, T.; De Gendt, S.

In: Surface and Interface Analysis, Vol. 42, No. 6-7, 06.2010, p. 1057-1060.

Research output: Contribution to journalArticle

TY - JOUR

T1 - A comparative X-ray photoelectron spectroscopy and medium-energy ion-scattering study of ultra-thin, Hf-based high-k films

AU - Sygellou, L.

AU - Ladas, S.

AU - Reading, M. A.

AU - Van Den Berg, J. A.

AU - Conard, T.

AU - De Gendt, S.

PY - 2010/6

Y1 - 2010/6

N2 - Ultra-thin high-k layers based on HfO2, or Hf-silicates in combination with sub-nanometer SiO2, show muchpromise in their use as Si-compatible gate dielectrics. XPS has been applied on a range of HfO2/SiO2and HfSiOx(60%Hf)/SiO2films on Si(100), before and after decoupled plasma nitridation (DPN) at 1073 K. The treatment of the data was optimized in order to determine individual layer thicknesses of the multilayer stack taking into account the measured nitrogen content of the nitrided films. The procedure adhered to the prescriptions of ISO18118:2004(E) for the calculations of inelastic mean free paths (IMFP) and elastic corrections thereof, using film material properties, like densities and band gaps. Effective attenuation lengths (EAL) were taken throughout as 90% of the respective IMFP, whereas an appropriate set of empirical relative sensitivity factors (RSF) was used. The XPS-derived thicknesses were compared with corresponding values obtained from medium-energy ion scattering (MEIS) measurements on the same series of specimens in combination with energy spectrum simulation to provide quantitative layer information with sub-nanometer resolution. The XPS and MEIS results exhibit very good agreement on the deduced layer structures within the respective experimental uncertainty, and both sets are consistent with the grown nominal layer parameters of the high-k nanofilms. 

AB - Ultra-thin high-k layers based on HfO2, or Hf-silicates in combination with sub-nanometer SiO2, show muchpromise in their use as Si-compatible gate dielectrics. XPS has been applied on a range of HfO2/SiO2and HfSiOx(60%Hf)/SiO2films on Si(100), before and after decoupled plasma nitridation (DPN) at 1073 K. The treatment of the data was optimized in order to determine individual layer thicknesses of the multilayer stack taking into account the measured nitrogen content of the nitrided films. The procedure adhered to the prescriptions of ISO18118:2004(E) for the calculations of inelastic mean free paths (IMFP) and elastic corrections thereof, using film material properties, like densities and band gaps. Effective attenuation lengths (EAL) were taken throughout as 90% of the respective IMFP, whereas an appropriate set of empirical relative sensitivity factors (RSF) was used. The XPS-derived thicknesses were compared with corresponding values obtained from medium-energy ion scattering (MEIS) measurements on the same series of specimens in combination with energy spectrum simulation to provide quantitative layer information with sub-nanometer resolution. The XPS and MEIS results exhibit very good agreement on the deduced layer structures within the respective experimental uncertainty, and both sets are consistent with the grown nominal layer parameters of the high-k nanofilms. 

KW - Hafnium silicate

KW - HfO 2

KW - High-k nanofilms

KW - Layerthickness measurement

KW - MEIS

KW - XPS

UR - http://www.scopus.com/inward/record.url?scp=77954256249&partnerID=8YFLogxK

U2 - 10.1002/sia.3251

DO - 10.1002/sia.3251

M3 - Article

VL - 42

SP - 1057

EP - 1060

JO - Surface and Interface Analysis

T2 - Surface and Interface Analysis

JF - Surface and Interface Analysis

SN - 0142-2421

IS - 6-7

ER -