Thermal stability of magnetic tunnel junctions with new amorphous ZrAl-alloy films as the under and capping layers

Chul Min Choi, Jin Oh Song, Seong Rae Lee

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

We studied the thermal stability of new amorphous ZrAl-based magnetic tunnel junctions (MTJs) with a ZrAl-oxide barrier replacing the Ta layers traditionally used for the under and capping layers. The MTJs were compared with similar conventional MTJs (Ta-based MTJ with Al-oxide). After annealing at various temperatures up to 450°C, the ZrAl-based MTJs still had a significant tunnel magnetoresistance signal of nearly 21%. The thermal stability of amorphous ZrAl-based and conventional Ta-based MTJs differs dramatically, mainly because of the different microstructural evolution. The noncrystalline ZrAl-alloy film had superior surface uniformity and an induced microstructure that resisted interdiffusion, with dense, equiaxed grains making up the upper stacks' films. By contrast, the conventional Ta-based MTJ had a broad columnar structure with less dense boundaries, which act as a source of interdiffusion, resulting in barrier deformation at elevated temperatures.

Original languageEnglish
Pages (from-to)2667-2669
Number of pages3
JournalIEEE Transactions on Magnetics
Volume41
Issue number10
DOIs
Publication statusPublished - 2005 Oct 1

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Tunnel junctions
Amorphous alloys
tunnel junctions
Thermodynamic stability
thermal stability
Oxides
oxides
Microstructural evolution
Magnetoresistance
tunnels
Tunnels
Annealing
Temperature
microstructure
Microstructure
annealing
temperature

Keywords

  • Amorphous ZrAl alloy
  • Magnetic tunnel junction
  • Thermal stability

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Physics and Astronomy (miscellaneous)

Cite this

Thermal stability of magnetic tunnel junctions with new amorphous ZrAl-alloy films as the under and capping layers. / Choi, Chul Min; Song, Jin Oh; Lee, Seong Rae.

In: IEEE Transactions on Magnetics, Vol. 41, No. 10, 01.10.2005, p. 2667-2669.

Research output: Contribution to journalArticle

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