Scanning carrier current method for in-situ measurement of flying height variation

Author

Yuan, Zhi-Min ; Liu, Bo ; Hu, Sheng-Bin ; Leng, Qing-Fang ; Chen, Qi-suo

Author_Institution

Data Storage Inst., Singapore

Volume

37

Issue

4

fYear

2001

fDate

7/1/2001 12:00:00 AM

Firstpage

1814

Lastpage

1817

Abstract

A novel writing process based in-situ flying height measurement method, scanning carrier current method, is proposed. An erasure current oscillating in the frequency range of 200~800 kHz is injected to the write head during the period of interest. Later, its effect on previously written data is detected to infer the flying height during the period of interest. The maximum scanning carrier current method provides a good solution to measure flying height variation in a large range during dynamic transient process. When the slider is in steady flying status, a lower scanning carrier current method can reduce the noise caused by media´s MrT fluctuation, whilst a biased scanning carrier current method is suitable to reduce the noise caused by media´s coercivity fluctuation in the flying height testing process

Keywords

coercive force; magnetic disc storage; magnetic heads; 200 to 800 kHz; MrT fluctuation; coercivity fluctuation; dynamic transient process; erasure current; flying height variation; in-situ measurement; scanning carrier current method; steady flying status; write head; writing process; Coercive force; Current measurement; Fluctuations; Frequency; Magnetic heads; Magnetic noise; Noise reduction; Rough surfaces; Testing; Writing;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.950976

Filename

950976