Browse Prior Art Database

Induced Anisotropy in Magneto Optic Films

IP.com Disclosure Number: IPCOM000092069D
Original Publication Date: 1968-Aug-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 31K

Publishing Venue

IBM

Related People

Ahn, KY: AUTHOR

Abstract

A method of inducing a uniaxial anisotropy in EuO films and other films of magneto-optic materials is provided for application in a beam addressable memory. Drawings A and B show two cross-sections of etched lines obtained by ion and chemical etching respectively. The ion etching or sputter etching gives a very sharp edge as compared with that of chemical process. Sharp edges are utilized to induce shape anisotropy in EuO films.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 83% of the total text.

Page 1 of 2

Induced Anisotropy in Magneto Optic Films

A method of inducing a uniaxial anisotropy in EuO films and other films of magneto-optic materials is provided for application in a beam addressable memory. Drawings A and B show two cross-sections of etched lines obtained by ion and chemical etching respectively. The ion etching or sputter etching gives a very sharp edge as compared with that of chemical process. Sharp edges are utilized to induce shape anisotropy in EuO films.

Drawing C shows a cross-section of the beam addressable memory plane. Bits of information are written along the wide strips, e.g., 3 micron wide, separated by barrier strips of 1 micron in width and height. Because of the induced anisotropy, the magnetization tends to remain along the direction of strips. This uniform magnetization, as compared with a planar geometry in which the magnetization curls, gives rise to a higher magneto-optic rotation, e.g., by a factor of two to three. Further, these strips tend to minimize the creeping effect because of sharp discontinuous edges. The barrier strips of high-conductivity metals also aid in maintaining more uniform temperatures in the active memory area as compared with a planar geometry.

The fabrication process consists of the following steps. There is evaporation of 1 micron thick metal films of high-thermal conductivity, e.g., Au, Ag, and Cu and their alloys. Strips whose width to be determined by memory specifications, e.g., from 3 to 5 microns are i...