Browse Prior Art Database

Permalloy Films for Bias Layers in Bubble Domain Devices

IP.com Disclosure Number: IPCOM000075804D
Original Publication Date: 1971-Nov-01
Included in the Prior Art Database: 2005-Feb-24
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Ahn, KY: AUTHOR [+2]

Abstract

Magnetically hard permalloy layers are used to provide a bias field for bubble domain devices. For instance, a crystal of DyFeO(3) is provided with a magnetically hard permalloy layer, which reduces the bias field requirements for bubble domain devices.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 1

Permalloy Films for Bias Layers in Bubble Domain Devices

Magnetically hard permalloy layers are used to provide a bias field for bubble domain devices. For instance, a crystal of DyFeO(3) is provided with a magnetically hard permalloy layer, which reduces the bias field requirements for bubble domain devices.

The permalloy layer is prepared by arc melting of 83-17 NiFe alloy with 25% of Co (by weight), which is added during the process. The permalloy films are deposited on the bubble domain material in the pressure range of 6x10/-8/ Torr - 1x10/-7/ Torr at a typical evaporation rate of 3.5 angstroms/second. The bias layer has a thickness of approximately 1500 angstroms. It is magnetically hardened by annealing in air while checking the bias field requirements.

Use of a magnetically hard permalloy bias layer decreases the bias field which must be supplied by external means, by at least 25%, Another advantage is that these permalloy layers do not have to grow epitaxially and are easily deposited on any magnetic films by vacuum deposition. The magnetic hardness is easily controlled, which will in turn control the bias field requirement of bubble domain devices.

1