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Title: Understanding the mechanisms of interfacial reactions during TiO{sub 2} layer growth on RuO{sub 2} by atomic layer deposition with O{sub 2} plasma or H{sub 2}O as oxygen source

Abstract

In this paper, TiO{sub 2} layers grown on RuO{sub 2} by atomic layer deposition (ALD) using tetrakis (dimethyla-mino) titanium (TDMAT) and either oxygen plasma or H{sub 2}O as oxygen source were analyzed using X-ray diffraction (XRD), Raman spectroscopy, and depth-resolved X-ray Photoelectron spectroscopy (XPS). The main objective is to investigate the surface chemical reactions mechanisms and their influence on the TiO{sub 2} film properties. The experimental results using XRD show that ALD deposition using H{sub 2}O leads to anatase TiO{sub 2} whereas a rutile TiO{sub 2} is obtained when oxygen-plasma is used as oxygen source. Depth-resolved XPS analysis allows to determine the reaction mechanisms at the RuO{sub 2} substrate surface after growth of thin TiO{sub 2} layers. Indeed, the XPS analysis shows that when H{sub 2}O assisted ALD process is used, intermediate Ti{sub 2}O{sub 3} layer is obtained and RuO{sub 2} is reduced into Ru as evidenced by high resolution transmission electron microscopy. In this case, there is no possibility to re-oxidize the Ru surface into RuO{sub 2} due to the weak oxidation character of H{sub 2}O and an anatase TiO{sub 2} layer is therefore grown on Ti{sub 2}O{sub 3}. In contrast, when oxygen plasma is used in the ALDmore » process, its strong oxidation character leads to the re-oxidation of the partially reduced RuO{sub 2} following the first Ti deposition step. Consequently, the RuO{sub 2} surface is regenerated, allowing the growth of rutile TiO{sub 2}. A surface chemical reaction scheme is proposed that well accounts for the observed experimental results.« less

Authors:
; ; ; ; ;  [1]
  1. Microelectronics Technology Laboratory (LTM), Grenoble Alpes University (UGA) and National Center for Scientific Research - CNRS, Grenoble 38000 (France)
Publication Date:
OSTI Identifier:
22598848
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DEPOSITION; DEPTH; ELECTRONS; FILMS; LAYERS; OXIDATION; OXYGEN; PLASMA; RAMAN SPECTROSCOPY; REACTION KINETICS; RESOLUTION; RUTHENIUM OXIDES; RUTILE; SURFACES; TITANIUM; TITANIUM OXIDES; TRANSMISSION ELECTRON MICROSCOPY; WATER; X-RAY DIFFRACTION; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Chaker, A., Szkutnik, P. D., Pointet, J., Gonon, P., Vallée, C., and Bsiesy, A., E-mail: ahmad.bsiesy@cea.fr. Understanding the mechanisms of interfacial reactions during TiO{sub 2} layer growth on RuO{sub 2} by atomic layer deposition with O{sub 2} plasma or H{sub 2}O as oxygen source. United States: N. p., 2016. Web. doi:10.1063/1.4960139.
Chaker, A., Szkutnik, P. D., Pointet, J., Gonon, P., Vallée, C., & Bsiesy, A., E-mail: ahmad.bsiesy@cea.fr. Understanding the mechanisms of interfacial reactions during TiO{sub 2} layer growth on RuO{sub 2} by atomic layer deposition with O{sub 2} plasma or H{sub 2}O as oxygen source. United States. doi:10.1063/1.4960139.
Chaker, A., Szkutnik, P. D., Pointet, J., Gonon, P., Vallée, C., and Bsiesy, A., E-mail: ahmad.bsiesy@cea.fr. 2016. "Understanding the mechanisms of interfacial reactions during TiO{sub 2} layer growth on RuO{sub 2} by atomic layer deposition with O{sub 2} plasma or H{sub 2}O as oxygen source". United States. doi:10.1063/1.4960139.
@article{osti_22598848,
title = {Understanding the mechanisms of interfacial reactions during TiO{sub 2} layer growth on RuO{sub 2} by atomic layer deposition with O{sub 2} plasma or H{sub 2}O as oxygen source},
author = {Chaker, A. and Szkutnik, P. D. and Pointet, J. and Gonon, P. and Vallée, C. and Bsiesy, A., E-mail: ahmad.bsiesy@cea.fr},
abstractNote = {In this paper, TiO{sub 2} layers grown on RuO{sub 2} by atomic layer deposition (ALD) using tetrakis (dimethyla-mino) titanium (TDMAT) and either oxygen plasma or H{sub 2}O as oxygen source were analyzed using X-ray diffraction (XRD), Raman spectroscopy, and depth-resolved X-ray Photoelectron spectroscopy (XPS). The main objective is to investigate the surface chemical reactions mechanisms and their influence on the TiO{sub 2} film properties. The experimental results using XRD show that ALD deposition using H{sub 2}O leads to anatase TiO{sub 2} whereas a rutile TiO{sub 2} is obtained when oxygen-plasma is used as oxygen source. Depth-resolved XPS analysis allows to determine the reaction mechanisms at the RuO{sub 2} substrate surface after growth of thin TiO{sub 2} layers. Indeed, the XPS analysis shows that when H{sub 2}O assisted ALD process is used, intermediate Ti{sub 2}O{sub 3} layer is obtained and RuO{sub 2} is reduced into Ru as evidenced by high resolution transmission electron microscopy. In this case, there is no possibility to re-oxidize the Ru surface into RuO{sub 2} due to the weak oxidation character of H{sub 2}O and an anatase TiO{sub 2} layer is therefore grown on Ti{sub 2}O{sub 3}. In contrast, when oxygen plasma is used in the ALD process, its strong oxidation character leads to the re-oxidation of the partially reduced RuO{sub 2} following the first Ti deposition step. Consequently, the RuO{sub 2} surface is regenerated, allowing the growth of rutile TiO{sub 2}. A surface chemical reaction scheme is proposed that well accounts for the observed experimental results.},
doi = {10.1063/1.4960139},
journal = {Journal of Applied Physics},
number = 8,
volume = 120,
place = {United States},
year = 2016,
month = 8
}
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