Magnetic properties of NdFeB thin films on platinum underlayers

Author

Mapps, D.J. ; Chandrasekhar, R. ; Grady, K.O. ; Cambridge, J. ; Long, A. Petford ; Doole, R.

Author_Institution

Centre for Res. in Inf. Storage Technol., Plymouth Univ., UK

Volume

33

Issue

5

fYear

1997

fDate

9/1/1997 12:00:00 AM

Firstpage

3007

Lastpage

3009

Abstract

A series of NdFeB (Nd₁₂Fe₈₂B₆) films of different thicknesses were r.f. sputtered on 1000 Å-thick Pt underlayers for information storage application. The perpendicular coercivity has a maximum of 3000 Oe for a 1000 Å - thick film annealed at 625°C for fifteen minutes. By using Transmission Electron Microscopy (TEM) we have found that the film is tetragonal with an additional fcc structure. The crystallographic texture is established during annealing at 625°C. The TEM micrographs show some voids and a grain size in the range 30 to 50 nm. For films annealed at 700°C for fifteen minutes, the voids disappeared and the grain size was found to be 100 nm. X-Ray Diffraction analysis of the annealed sample indicates that the NdFeB film is amorphous. Annealing at 625°C produces the 2:15:1 phase in the films

Keywords

X-ray diffraction; amorphous magnetic materials; annealing; boron alloys; coercive force; digital magnetic recording; ferromagnetic materials; grain size; iron alloys; neodymium alloys; sputter deposition; transmission electron microscopy; voids (solid); 100 angstrom; 30 to 50 nm; 625 to 700 degC; NdFeB-Pt; RF sputtering; TEM; X-ray diffraction analysis; annealing; crystallographic texture; digital magnetic recording; grain size; information storage application; perpendicular coercivity; voids; Annealing; Coercive force; Grain size; Iron; Magnetic films; Magnetic properties; Neodymium; Platinum; Sputtering; Thick films;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.617826

Filename

617826