Magnetoresistive memory soi cell

Abstract

A ferromagnetic thin-film based digital memory having a substrate formed of a base supporting an electrically insulating material primary substrate layer in turn supporting a plurality of current control devices each having an interconnection arrangement with each of said plurality of current control devices being separated from one another by spacer material therebetween and being electrically interconnected with information storage and retrieval circuitry. A plurality of bit structures are each supported on and electrically connected to a said interconnection arrangement of a corresponding one of said plurality of current control devices and have magnetic material films in which a characteristic magnetic property is substantially maintained below an associated critical temperature above which such magnetic property is not maintained of which two are separated by at least one intermediate layer of a nonmagnetic material having two major surfaces on opposite sides thereof. A plurality of word line structures located across from a corresponding one of the bit structures on an opposite side of the intermediate layer of a corresponding one of said bit structures from its interconnection arrangement supporting that bit structure. Sufficient electrical current selectively drawn through each of these bit structures as interconnected can cause substantial heating of that bit structure to raise temperatures thereof to have at least one of the magnetic material films therein at least approach its corresponding associated critical temperature while being substantially above temperatures of at least an adjacent said bit structure because of sufficient thermal isolation.