Comparison of magnetic fields of thin-film heads and their corresponding bit patterns using magnetic force microscopy

Author

Rice, Paul ; Hallett, Bill ; Moreland, John

Author_Institution

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

Volume

30

Issue

6

fYear

1994

fDate

11/1/1994 12:00:00 AM

Firstpage

4248

Lastpage

4250

Abstract

We have used dc-mode magnetic force microscopy to image the magnetic fringing fields of several thin-film heads and the bit patterns written with these heads. The images were taken with Si₃N₄ tips coated with 10-nm Fe and 5-nm Au. The heads and disks are typical industry standards. The heads had a variety of pole piece configurations. A large track separation was used so that the erase bands could be thoroughly studied. We were surprised to discover magnetic fields that correspond to layers in the alumina overcoat near the pole pieces. The magnetic force microscope images of the bit pattern show a definite twist at the track edge that points toward the trailing pole piece. We also observed disk magnetization patterns that remained after an ac erase procedure

Keywords

magnetic field measurement; magnetic force microscopy; magnetic heads; magnetic thin film devices; magnetisation; AC erase procedure; Au; Au coating; DC-mode; Fe; Fe coating; Si₃N₄; Si₃N₄ tips; alumina overcoat; bit patterns; disk magnetization patterns; erase bands; industry standards; large track separation; magnetic fields; magnetic force microscopy; magnetic fringing fields; pole piece configurations; pole pieces; thin-film heads; track edge; trailing pole piece; Atomic force microscopy; Iron; Magnetic fields; Magnetic films; Magnetic force microscopy; Magnetic forces; Magnetic heads; Magnetic separation; Magnetization; Springs;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.334050

Filename

334050