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Title: The effect of interfacial layer properties on the performance of Hf-based gate stack devices

Abstract

The influence of Hf-based dielectrics on the underlying SiO2 interfacial layer IL in high-k gate stacks is investigated. An increase in the IL dielectric constant, which correlates to an increase of the positive fixed charge density in the IL, is found to depend on the starting, pre-high-k deposition thickness of the IL. Electron energy-loss spectroscopy and electron spin resonance spectra exhibit signatures of the high-k-induced oxygen deficiency in the IL consistent with the electrical data. It is concluded that high temperature processing generates oxygen vacancies in the IL responsible for the observed trend in transistor performance.

Authors:
 [1];  [2];  [2];  [2];  [2];  [2];  [2];  [2];  [3];  [4];  [4];  [5];  [5]
  1. Sematech, Austin, TX
  2. International Sematech
  3. ADTF
  4. ORNL
  5. Pennsylvania State University
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
930876
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 100
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CHARGE DENSITY; DIELECTRIC MATERIALS; ELECTRON SPIN RESONANCE; ENERGY-LOSS SPECTROSCOPY; PERFORMANCE; HAFNIUM; alternate gate dielectrics

Citation Formats

Bersuker, Gennadi, Park, C S, Barnett, J, Lysaght, P, Kirsch, P D, Young, C D, Choi, R, Lee, B H, Foran, B, van Benthem, Klaus, Pennycook, Stephen J, Lenahan, P M, and Ryan, J T. The effect of interfacial layer properties on the performance of Hf-based gate stack devices. United States: N. p., 2006. Web. doi:10.1063/1.2362905.
Bersuker, Gennadi, Park, C S, Barnett, J, Lysaght, P, Kirsch, P D, Young, C D, Choi, R, Lee, B H, Foran, B, van Benthem, Klaus, Pennycook, Stephen J, Lenahan, P M, & Ryan, J T. The effect of interfacial layer properties on the performance of Hf-based gate stack devices. United States. doi:10.1063/1.2362905.
Bersuker, Gennadi, Park, C S, Barnett, J, Lysaght, P, Kirsch, P D, Young, C D, Choi, R, Lee, B H, Foran, B, van Benthem, Klaus, Pennycook, Stephen J, Lenahan, P M, and Ryan, J T. Sun . "The effect of interfacial layer properties on the performance of Hf-based gate stack devices". United States. doi:10.1063/1.2362905.
@article{osti_930876,
title = {The effect of interfacial layer properties on the performance of Hf-based gate stack devices},
author = {Bersuker, Gennadi and Park, C S and Barnett, J and Lysaght, P and Kirsch, P D and Young, C D and Choi, R and Lee, B H and Foran, B and van Benthem, Klaus and Pennycook, Stephen J and Lenahan, P M and Ryan, J T},
abstractNote = {The influence of Hf-based dielectrics on the underlying SiO2 interfacial layer IL in high-k gate stacks is investigated. An increase in the IL dielectric constant, which correlates to an increase of the positive fixed charge density in the IL, is found to depend on the starting, pre-high-k deposition thickness of the IL. Electron energy-loss spectroscopy and electron spin resonance spectra exhibit signatures of the high-k-induced oxygen deficiency in the IL consistent with the electrical data. It is concluded that high temperature processing generates oxygen vacancies in the IL responsible for the observed trend in transistor performance.},
doi = {10.1063/1.2362905},
journal = {Journal of Applied Physics},
number = ,
volume = 100,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
  • Abstract not provided.
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