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Title: Kinetics and intermediate phases in epitaxial growth of Fe{sub 3}O{sub 4} films from deposition and thermal reduction

Abstract

We have studied the kinetics of the transitions between the Fe{sub 2}O{sub 3} and Fe{sub 3}O{sub 4} phases as thin epilayers (∼2.5 nm) on Al{sub 2}O{sub 3} (001) substrates using time-resolved reflection high energy electron diffraction. The different iron oxide phases were identified using a combination of in-situ and ex-situ characterizations. The transition from an α-Fe{sub 2}O{sub 3} (001) epilayer to a Fe{sub 3}O{sub 4} (111) epilayer through thermal reduction was found to be determined by the Fe-O bonding energy, resulting in a long time scale. The oxidation at high temperature converts a Fe{sub 3}O{sub 4} (111) epilayer to an α-Fe{sub 2}O{sub 3} (001) epilayer quickly; at low temperature, a γ-Fe{sub 2}O{sub 3} (111) epilayer was slowly generated instead. By repeating the deposition/thermal reduction processes, a thicker Fe{sub 3}O{sub 4} (111) film was obtained, which exhibit high crystallinity and moderate magnetic coercivity.

Authors:
 [1];  [2]; ;  [1];  [3]
  1. School of Science, MOE Key Laboratory for Non-Equilibrium Synthesis and Modulation of Condensed Matter, Xi'an Jiaotong University, Xi'an 710049, ShaanXi (China)
  2. (United States)
  3. Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588 (United States)
Publication Date:
OSTI Identifier:
22598846
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:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM OXIDES; BONDING; COERCIVE FORCE; DEPOSITION; ELECTRON DIFFRACTION; EPITAXY; FERRITES; FILMS; IRON OXIDES; IRON-ALPHA; KINETICS; OXIDATION; REDUCTION; REFLECTION; SUBSTRATES; TEMPERATURE RANGE 0065-0273 K; TEMPERATURE RANGE 0400-1000 K; TIME RESOLUTION

Citation Formats

Zhang, Xiaozhe, Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, Yang, Sen, Yang, Zhimao, E-mail: zmyang@xjtu.edu.cn, E-mail: xiaoshan.xu@unl.edu, and Xu, Xiaoshan, E-mail: zmyang@xjtu.edu.cn, E-mail: xiaoshan.xu@unl.edu. Kinetics and intermediate phases in epitaxial growth of Fe{sub 3}O{sub 4} films from deposition and thermal reduction. United States: N. p., 2016. Web. doi:10.1063/1.4961607.
Zhang, Xiaozhe, Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, Yang, Sen, Yang, Zhimao, E-mail: zmyang@xjtu.edu.cn, E-mail: xiaoshan.xu@unl.edu, & Xu, Xiaoshan, E-mail: zmyang@xjtu.edu.cn, E-mail: xiaoshan.xu@unl.edu. Kinetics and intermediate phases in epitaxial growth of Fe{sub 3}O{sub 4} films from deposition and thermal reduction. United States. doi:10.1063/1.4961607.
Zhang, Xiaozhe, Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, Yang, Sen, Yang, Zhimao, E-mail: zmyang@xjtu.edu.cn, E-mail: xiaoshan.xu@unl.edu, and Xu, Xiaoshan, E-mail: zmyang@xjtu.edu.cn, E-mail: xiaoshan.xu@unl.edu. 2016. "Kinetics and intermediate phases in epitaxial growth of Fe{sub 3}O{sub 4} films from deposition and thermal reduction". United States. doi:10.1063/1.4961607.
@article{osti_22598846,
title = {Kinetics and intermediate phases in epitaxial growth of Fe{sub 3}O{sub 4} films from deposition and thermal reduction},
author = {Zhang, Xiaozhe and Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588 and Yang, Sen and Yang, Zhimao, E-mail: zmyang@xjtu.edu.cn, E-mail: xiaoshan.xu@unl.edu and Xu, Xiaoshan, E-mail: zmyang@xjtu.edu.cn, E-mail: xiaoshan.xu@unl.edu},
abstractNote = {We have studied the kinetics of the transitions between the Fe{sub 2}O{sub 3} and Fe{sub 3}O{sub 4} phases as thin epilayers (∼2.5 nm) on Al{sub 2}O{sub 3} (001) substrates using time-resolved reflection high energy electron diffraction. The different iron oxide phases were identified using a combination of in-situ and ex-situ characterizations. The transition from an α-Fe{sub 2}O{sub 3} (001) epilayer to a Fe{sub 3}O{sub 4} (111) epilayer through thermal reduction was found to be determined by the Fe-O bonding energy, resulting in a long time scale. The oxidation at high temperature converts a Fe{sub 3}O{sub 4} (111) epilayer to an α-Fe{sub 2}O{sub 3} (001) epilayer quickly; at low temperature, a γ-Fe{sub 2}O{sub 3} (111) epilayer was slowly generated instead. By repeating the deposition/thermal reduction processes, a thicker Fe{sub 3}O{sub 4} (111) film was obtained, which exhibit high crystallinity and moderate magnetic coercivity.},
doi = {10.1063/1.4961607},
journal = {Journal of Applied Physics},
number = 8,
volume = 120,
place = {United States},
year = 2016,
month = 8
}
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