Garnet films for 64 Mb bubble memory devices

Author

Hosoe, Y. ; Imura, R. ; Suzuki, R. ; Ikeda, T.

Author_Institution

Hitachi Ltd., Tokyo, Japan

Volume

25

Issue

5

fYear

1989

fDate

9/1/1989 12:00:00 AM

Firstpage

4254

Lastpage

4256

Abstract

Garnet films of (BiSmLu)₃(FeAl)₅O₁₂ supporting 0.4-0.45-μm diameter bubbles have been studied for use in 64-Mb bubble memory devices. Using CaMgZr:GGG substrates with a large lattice constant (12.498 Å), the anisotropy energy K_u can be increased to 2.5×10⁵ erg/cm³ by increasing the Sm content in the film. Consequently, the bubble diameter can be reduced to 0.4-0.45 μm, keeping the effective anisotropy field (H_k-4πM_s) at more than 1500 Oe. For the films on GGG with a K_u value of about 1.8-10⁵ erg/cm³, the value of H_k and/or the film thickness must be decreased compared to the values for films on CaMgZr:GGG in order to reduce the bubble diameter to less than 0.45 μm

Keywords

bismuth compounds; garnets; magnetic bubble memories; magnetic thin films; (BiSmLu)₃(FeAl)₅O₁₂ garnet films; 0.4 to 0.45 micron; 64 Mbit; CaMgZr-GdGG; CaMgZr-GdGa5O12; anisotropy energy; anisotropy field; bubble diameter; lattice constant; Anisotropic magnetoresistance; Bismuth; Garnet films; Iron; Lattices; Magnetic resonance; Spectroscopy; Strips; Substrates; Wavelength measurement;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.42586

Filename

42586