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Title: Mechanisms of arsenic segregation to the Ni{sub 2}Si/SiO{sub 2} interface during Ni{sub 2}Si formation

Abstract

We have investigated the mechanisms of As redistribution during Ni{sub 2}Si formation on polycrystalline Si/SiO{sub 2} and amorphous Si/SiO{sub 2} stacks on (100) Si by secondary ion mass spectroscopy measurements. We found a significant impact of the Si crystallinity and pre-silicidation thermal treatments on the dopant redistribution. There is a significantly higher dose of As accumulated in the vicinity of SiO{sub 2} after full Ni{sub 2}Si silicidation on poly-Si ({approx}51%) than on amorphous-Si ({approx}13%). We demonstrate that the As redistribution during Ni{sub 2}Si formation on amorphous silicon is dominated by snowplow of As in front of the growing silicide. In contrast, when Ni{sub 2}Si is formed on recrystallized poly-silicon there are three segregation mechanisms: (1) thermal diffusion during high temperature recrystallization annealing ({approx}17%) (2) snowplow during silicidation ({approx}13%), not dependent on the substrate crystallinity and (3) diffusion along poly-Si grain boundaries during silicidation ({approx}22%)

Authors:
; ; ; ; ; ;  [1];  [2];  [2];  [2];  [2];  [2]
  1. IKS, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, 3001 Leuven (Belgium)
  2. (Belgium)
Publication Date:
OSTI Identifier:
20706407
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 87; Journal Issue: 18; Other Information: DOI: 10.1063/1.2125124; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AMORPHOUS STATE; ANNEALING; ARSENIC; GRAIN BOUNDARIES; INTERFACES; ION MICROPROBE ANALYSIS; MASS SPECTRA; MASS SPECTROSCOPY; NICKEL COMPOUNDS; POLYCRYSTALS; RECRYSTALLIZATION; SEGREGATION; SEMICONDUCTOR MATERIALS; SILICON; SILICON OXIDES; SUBSTRATES

Citation Formats

Pawlak, M.A., Janssens, T., Lauwers, A., Vantomme, A., Vandervorst, W., Maex, K., Kittl, J.A., IMEC, Kapeldreef 75, 3001 Leuven, IMEC, Kapeldreef 75, 3001 Leuven, IKS, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, 3001 Leuven, E.E. Department Katholieke Universiteit Leuven and IMEC, Kapeldreef 75, 3001 Leuven, and Affiliate at IMEC from Texas Instruments IMEC, Kapeldreef 75, 3001 Leuven. Mechanisms of arsenic segregation to the Ni{sub 2}Si/SiO{sub 2} interface during Ni{sub 2}Si formation. United States: N. p., 2005. Web. doi:10.1063/1.2125124.
Pawlak, M.A., Janssens, T., Lauwers, A., Vantomme, A., Vandervorst, W., Maex, K., Kittl, J.A., IMEC, Kapeldreef 75, 3001 Leuven, IMEC, Kapeldreef 75, 3001 Leuven, IKS, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, 3001 Leuven, E.E. Department Katholieke Universiteit Leuven and IMEC, Kapeldreef 75, 3001 Leuven, & Affiliate at IMEC from Texas Instruments IMEC, Kapeldreef 75, 3001 Leuven. Mechanisms of arsenic segregation to the Ni{sub 2}Si/SiO{sub 2} interface during Ni{sub 2}Si formation. United States. doi:10.1063/1.2125124.
Pawlak, M.A., Janssens, T., Lauwers, A., Vantomme, A., Vandervorst, W., Maex, K., Kittl, J.A., IMEC, Kapeldreef 75, 3001 Leuven, IMEC, Kapeldreef 75, 3001 Leuven, IKS, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, 3001 Leuven, E.E. Department Katholieke Universiteit Leuven and IMEC, Kapeldreef 75, 3001 Leuven, and Affiliate at IMEC from Texas Instruments IMEC, Kapeldreef 75, 3001 Leuven. Mon . "Mechanisms of arsenic segregation to the Ni{sub 2}Si/SiO{sub 2} interface during Ni{sub 2}Si formation". United States. doi:10.1063/1.2125124.
@article{osti_20706407,
title = {Mechanisms of arsenic segregation to the Ni{sub 2}Si/SiO{sub 2} interface during Ni{sub 2}Si formation},
author = {Pawlak, M.A. and Janssens, T. and Lauwers, A. and Vantomme, A. and Vandervorst, W. and Maex, K. and Kittl, J.A. and IMEC, Kapeldreef 75, 3001 Leuven and IMEC, Kapeldreef 75, 3001 Leuven and IKS, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, 3001 Leuven and E.E. Department Katholieke Universiteit Leuven and IMEC, Kapeldreef 75, 3001 Leuven and Affiliate at IMEC from Texas Instruments IMEC, Kapeldreef 75, 3001 Leuven},
abstractNote = {We have investigated the mechanisms of As redistribution during Ni{sub 2}Si formation on polycrystalline Si/SiO{sub 2} and amorphous Si/SiO{sub 2} stacks on (100) Si by secondary ion mass spectroscopy measurements. We found a significant impact of the Si crystallinity and pre-silicidation thermal treatments on the dopant redistribution. There is a significantly higher dose of As accumulated in the vicinity of SiO{sub 2} after full Ni{sub 2}Si silicidation on poly-Si ({approx}51%) than on amorphous-Si ({approx}13%). We demonstrate that the As redistribution during Ni{sub 2}Si formation on amorphous silicon is dominated by snowplow of As in front of the growing silicide. In contrast, when Ni{sub 2}Si is formed on recrystallized poly-silicon there are three segregation mechanisms: (1) thermal diffusion during high temperature recrystallization annealing ({approx}17%) (2) snowplow during silicidation ({approx}13%), not dependent on the substrate crystallinity and (3) diffusion along poly-Si grain boundaries during silicidation ({approx}22%)},
doi = {10.1063/1.2125124},
journal = {Applied Physics Letters},
number = 18,
volume = 87,
place = {United States},
year = {Mon Oct 31 00:00:00 EST 2005},
month = {Mon Oct 31 00:00:00 EST 2005}
}
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