High frequency measurements of CoFeHfO thin films

Author

Russek, Stephen E. ; Kabos, Pavel ; Silva, Tom ; Mancoff, Frederick B. ; Wang, Dexin ; Qian, Zhenghong ; Daughton, James M.

Author_Institution

Nat. Inst. of Stand. & Technol., Boulder, CO, USA

Volume

37

Issue

4

fYear

2001

fDate

7/1/2001 12:00:00 AM

Firstpage

2248

Lastpage

2250

Abstract

High-frequency measurements of the transverse susceptibility and damping constant of CoFeHfO thin films have been made over a frequency range of 0.1 GHz to 6 GHz as a function of film resistivity, thickness, and temperature. The film resistivity varied from 250 μΩcm to 2100 μΩcm. The films show relatively low damping at high frequencies with the damping constant α ranging from 0.01 to 0.06. The damping constant increases with film resistivity and, for the highest resistivity films, the damping constant decreases as the thickness increases. The damping constant, induced anisotropy, and film resistivity show weak temperature dependence over a temperature range from 4 K to 300 K. The low damping constant, in conjunction with the high anisotropy, large resistivity, and large spin-dependent-tunneling magnetoresistance, makes this material attractive for several high-frequency magnetic device applications

Keywords

cobalt compounds; damping; electrical resistivity; ferromagnetic materials; hafnium compounds; induced anisotropy (magnetic); iron compounds; magnetic susceptibility; magnetic thin films; magnetoresistance; tunnelling; 0.1 to 6 GHz; 4 to 300 K; CoFeHfO; damping constant; electrical resistivity; ferromagnetic thin film; high-frequency magnetic device; induced anisotropy; spin-dependent-tunneling magnetoresistance; temperature dependence; transverse susceptibility; Conductivity; Damping; Frequency measurement; Magnetic films; Magnetic materials; Magnetoresistance; Temperature dependence; Temperature distribution; Thickness measurement; Transistors;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.951138

Filename

951138