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Title: Phase control of iridium and iridium oxide thin films in atomic layer deposition

Abstract

The atomic layer deposition of iridium (Ir) and iridium oxide (IrO{sub 2}) films was investigated using an alternating supply of (ethylcyclopentadienyl)(1,5-cyclooctadiene) iridium and oxygen gas at temperatures between 230 and 290 deg. C. The phase transition between Ir and IrO{sub 2} occurred at the critical oxygen partial pressure during the oxygen injection pulse. The oxygen partial pressure was controlled by the O{sub 2}/(Ar+O{sub 2}) ratio or deposition pressures. The resistivity of the deposited Ir and IrO{sub 2} films was about 9 and 120 {mu}{omega} cm, respectively. In addition, the critical oxygen partial pressure for the phase transition between Ir and IrO{sub 2} was increased with increasing the deposition temperature. Thus, the phase of the deposited film, either Ir or IrO{sub 2}, was controlled by the oxygen partial pressure and the deposition temperature. However, the formation of a thin Ir layer was detected between the IrO{sub 2} and SiO{sub 2} substrate. To remove this interfacial layer, the oxygen partial pressure is increased to a severe condition. And the impurity contents were below the detection limit of Auger electron spectroscopy in both Ir and IrO{sub 2} films.

Authors:
; ; ;  [1]
  1. Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)
Publication Date:
OSTI Identifier:
21064516
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 103; Journal Issue: 2; Other Information: DOI: 10.1063/1.2836965; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AUGER ELECTRON SPECTROSCOPY; DEPOSITION; ELECTRIC CONDUCTIVITY; IRIDIUM; IRIDIUM OXIDES; LAYERS; OXYGEN; PARTIAL PRESSURE; PHASE TRANSFORMATIONS; SILICON OXIDES; THIN FILMS

Citation Formats

Kim, Sung-Wook, Kwon, Se-Hun, Kwak, Dong-Kee, and Kang, Sang-Won. Phase control of iridium and iridium oxide thin films in atomic layer deposition. United States: N. p., 2008. Web. doi:10.1063/1.2836965.
Kim, Sung-Wook, Kwon, Se-Hun, Kwak, Dong-Kee, & Kang, Sang-Won. Phase control of iridium and iridium oxide thin films in atomic layer deposition. United States. doi:10.1063/1.2836965.
Kim, Sung-Wook, Kwon, Se-Hun, Kwak, Dong-Kee, and Kang, Sang-Won. 2008. "Phase control of iridium and iridium oxide thin films in atomic layer deposition". United States. doi:10.1063/1.2836965.
@article{osti_21064516,
title = {Phase control of iridium and iridium oxide thin films in atomic layer deposition},
author = {Kim, Sung-Wook and Kwon, Se-Hun and Kwak, Dong-Kee and Kang, Sang-Won},
abstractNote = {The atomic layer deposition of iridium (Ir) and iridium oxide (IrO{sub 2}) films was investigated using an alternating supply of (ethylcyclopentadienyl)(1,5-cyclooctadiene) iridium and oxygen gas at temperatures between 230 and 290 deg. C. The phase transition between Ir and IrO{sub 2} occurred at the critical oxygen partial pressure during the oxygen injection pulse. The oxygen partial pressure was controlled by the O{sub 2}/(Ar+O{sub 2}) ratio or deposition pressures. The resistivity of the deposited Ir and IrO{sub 2} films was about 9 and 120 {mu}{omega} cm, respectively. In addition, the critical oxygen partial pressure for the phase transition between Ir and IrO{sub 2} was increased with increasing the deposition temperature. Thus, the phase of the deposited film, either Ir or IrO{sub 2}, was controlled by the oxygen partial pressure and the deposition temperature. However, the formation of a thin Ir layer was detected between the IrO{sub 2} and SiO{sub 2} substrate. To remove this interfacial layer, the oxygen partial pressure is increased to a severe condition. And the impurity contents were below the detection limit of Auger electron spectroscopy in both Ir and IrO{sub 2} films.},
doi = {10.1063/1.2836965},
journal = {Journal of Applied Physics},
number = 2,
volume = 103,
place = {United States},
year = 2008,
month = 1
}
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