High frequency response of thin film heads by scanning Kerr effect microscopy

Author

Corb, B.W.

Author_Institution

Eastman Kodak Co., San Diego, CA, USA

Volume

24

Issue

6

fYear

1988

fDate

11/1/1988 12:00:00 AM

Firstpage

2838

Lastpage

2840

Abstract

A scanning Kerr effect microscope (SKEM) was built that features 0.025-μm step sizes and 5° phase resolution over a 50-MHz bandwidth. Scans were made on several NiFe and CoZr thin-film recording heads with different head geometries. The measured values of head saturation are in rough agreement with those calculated from a model for saturation near the back gap. The frequency response of the NiFe heads shows that the real component of the efficiency rolls off smoothly, and the imaginary component peaks between 15 and 40 MHz. The bandwidth increases with DC efficiency and is two to three times lower than computed values. The frequency response of the CoZr head showed peaks and valleys that were attributed to a misoriented easy axis. The response of the heads studied here is most likely determined by domain behavior

Keywords

Kerr magneto-optical effect; cobalt alloys; frequency response; iron alloys; magnetic heads; magnetic thin film devices; nickel alloys; zirconium alloys; 50 MHz; CoZr; DC efficiency; NiFe; bandwidth; domain behavior; frequency response; head geometries; head saturation; misoriented easy axis; scanning Kerr effect microscopy; thin film heads; Bandwidth; Design optimization; Eddy currents; Frequency response; Kerr effect; Magnetic heads; Magnetic materials; Magnetization; Microscopy; Transistors;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.92262

Filename

92262