Study of the Insulating Layer and Interfaces of MgO-Based Magnetic Tunnel Junctions by Impedance and Capacitance Spectra

Author

Huang, J.C.A. ; Hsu, C.Y. ; Chen, W.H. ; Lee, Y.H.

Author_Institution

Dept. of Phys., Nat. Cheng Kung Univ., Tainan

Volume

43

Issue

2

fYear

2007

Firstpage

911

Lastpage

913

Abstract

We have systematically investigated the complex impedance (CI) and complex capacitance (CC) spectra of MgO-based magnetic tunnel junctions (MTJs) due to successive annealing. The variation of the tunnel magnetoresistance (TMR) ratio due to annealing can be related to the change of interfacial trap states and textured MgO based on the analysis of CI spectra by an equivalent circuit model. The results of CC spectra are also consistent with the analysis of CI and observed TMR ratio variation. The CI and CC techniques are also powerful to characterize the oxide-based MTJs

Keywords

annealing; capacitance; electric impedance; insulating coatings; interface states; magnesium compounds; tunnelling magnetoresistance; MgO; TMR; annealing; complex capacitance spectra; complex impedance spectra; insulating layer; interfacial trap states; magnetic tunnel junctions; tunnel magnetoresistance; Annealing; Capacitance; Equivalent circuits; Impedance; Insulation; Magnetic analysis; Magnetic tunneling; Physics; Temperature; Tunneling magnetoresistance; Complex capacitance (CC); MgO; complex impedence (CI); equivalent circuit model (ECM); tunnel magnetoresistance (TMR);

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2006.888502

Filename

4069027