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Title: Effect of nitrogen upon structural and magnetic properties of FePt in FePt/AlN multilayer structures

Abstract

This paper investigates the effect of the addition of nitrogen in FePt layers for ultrathin FePt/AlN multilayer structures. X-ray diffraction results reveal that a compressive stress relaxation occurs after annealing owing to the release of interstitial nitrogen atoms in the FePt layers. The introduction of nitrogen also induces a large in-plane compressive strain during grain growth not seen in FePt deposited without nitrogen. This strain is considered to decrease the driving force for (111) grain growth and FePt ordering.

Authors:
; ; ; ; ;  [1]
  1. Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, 2-12-1 Oh-okayama, Meguro-ku, Tokyo 152-8552 (Japan)
Publication Date:
OSTI Identifier:
22318038
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 32; Journal Issue: 5; Other Information: (c) 2014 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM NITRIDES; GRAIN GROWTH; IRON COMPOUNDS; LAYERS; MAGNETIC PROPERTIES; NITROGEN; PLATINUM COMPOUNDS; STRESS RELAXATION; X-RAY DIFFRACTION

Citation Formats

Gao, Tenghua, E-mail: gao.t.ab@m.titech.ac.jp, Zhang, Cong, Sannomiya, Takumi, Muraishi, Shinji, Nakamura, Yoshio, and Shi, Ji. Effect of nitrogen upon structural and magnetic properties of FePt in FePt/AlN multilayer structures. United States: N. p., 2014. Web. doi:10.1116/1.4891562.
Gao, Tenghua, E-mail: gao.t.ab@m.titech.ac.jp, Zhang, Cong, Sannomiya, Takumi, Muraishi, Shinji, Nakamura, Yoshio, & Shi, Ji. Effect of nitrogen upon structural and magnetic properties of FePt in FePt/AlN multilayer structures. United States. doi:10.1116/1.4891562.
Gao, Tenghua, E-mail: gao.t.ab@m.titech.ac.jp, Zhang, Cong, Sannomiya, Takumi, Muraishi, Shinji, Nakamura, Yoshio, and Shi, Ji. Mon . "Effect of nitrogen upon structural and magnetic properties of FePt in FePt/AlN multilayer structures". United States. doi:10.1116/1.4891562.
@article{osti_22318038,
title = {Effect of nitrogen upon structural and magnetic properties of FePt in FePt/AlN multilayer structures},
author = {Gao, Tenghua, E-mail: gao.t.ab@m.titech.ac.jp and Zhang, Cong and Sannomiya, Takumi and Muraishi, Shinji and Nakamura, Yoshio and Shi, Ji},
abstractNote = {This paper investigates the effect of the addition of nitrogen in FePt layers for ultrathin FePt/AlN multilayer structures. X-ray diffraction results reveal that a compressive stress relaxation occurs after annealing owing to the release of interstitial nitrogen atoms in the FePt layers. The introduction of nitrogen also induces a large in-plane compressive strain during grain growth not seen in FePt deposited without nitrogen. This strain is considered to decrease the driving force for (111) grain growth and FePt ordering.},
doi = {10.1116/1.4891562},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 5,
volume = 32,
place = {United States},
year = {Mon Sep 01 00:00:00 EDT 2014},
month = {Mon Sep 01 00:00:00 EDT 2014}
}
  • It will be reported about the effect of the sputtering gases, Ar and Xe, on FePt clusters formation by magnetron sputtering deposition at high working pressures. All layers, with bulk equivalent thicknesses between 3 to 5 nm, were realized at RT by a sequential layer by layer deposition or a co-deposition of Fe and Pt. After rapid thermal annealing at 500 deg. C, the highest L1{sub 0} fraction was found using Xe as sputtering gas: Xe decreases the transformation activation energy and therefore, reduces the critical thickness necessary to obtain the high anistropic ferromagnetic phase. Ar assisted growths lead tomore » FePt clusters in the L1{sub 0} phase only if the sequential layer deposition is used, whereas for Xe no differences in the deposition techniques were observed.« less
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