Antiparallel magnetoresistive memory cells

Abstract

A ferromagnetic thin-film based digital memory having a plurality of bit structures electrically interconnected with information storage and retrieval circuitry that avoids information loss in one bit structure because of operating the others through this circuitry. Each of these bit structures formed of a relative orientation maintenance intermediate layer having two major surfaces on opposite sides thereof with a pair of memory films of an anisotropic ferromagnetic material each on a corresponding one of said relative orientation maintenance intermediate layer major surfaces. The relative orientation maintenance intermediate layer is of a material and a selected thickness so as to maintain magnetizations of said memory films oriented in substantially opposite directions. Interconnection electrodes pairs are each in electrically conductive contact with a corresponding one of the bit structures on substantially opposite sides thereof near or at substantially opposite edges of the relative orientation maintenance intermediate layer major surface. A magnetization reference direction layer able to maintain relatively well its magnetization orientation can be provided across a nonmagnetic layer from one of the pair of memory films with the nonmagnetic layer being either electrically conductive or insulative.