The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 12, 1978
Filed:
Apr. 11, 1977
Roger Edward Lund, Woodbury, MN (US);
Sperry Rand Corporation, New York, NY (US);
Abstract
Defining the structuring of bubble domains in a magnetizable layer of a bubble domain memory plane is determined by modifying the magnetic characteristics of the magnetizable layer in the confinement area. The bubble domain memory plane is comprised of a non-magnetic Gadolinium Gallium Garnet (GGG) layer which is a supporting layer upon which is formed by the liquid phase epitaxy (LPE) method a plurality of magnetizable layers in each of which a bubble domain is capable of being generated and sustained. Upon the memory plane are formed, as by any of many well-known deposition techniques, a matrix array of a parallel set of horizontally oriented X drive lines and an orthogonally oriented parallel set of Y drive lines. Each X drive line, Y drive line intersection of the matrix array defines a memory area having four quadrants. In only one of the four quadrants is there provided a bubble domain supporting magnetizable layer, all other areas of the memory plane having no magnetizable layer or a magnetizable layer of an insufficient thickness to support bubble domains therein. Accordingly, in only one of the four quadrants of each of the memory areas is there a magnetizable layer of sufficient thickness to support a bubble domain thereat.