Patent ID: 6914805
Filing Date: 2005-07-05
Classification: G11C

Abstract:
1. An MRAM device comprising: an MRAM bit having a magnetoresistive material whose electrical resistance depends on the magnetization of the magnetoresistive material wherein the change in the resistance permits the bit to be in different states; a magnetic field generating member positioned adjacent the bit wherein the magnetic field generating member is capable of generating a magnetic field that alters the magnetization of the bit, wherein the magnetic field generating member comprises a conductor that permits an electrical current to flow therethrough thereby generating the magnetic field; and a magnetic keeper member positioned adjacent the magnetic field generating member, the magnetic keeper member adapted to shape the pattern of the magnetic field generated by the magnetic field generating member, wherein the magnetic keeper member comprises a soft magnetic material that captures and concentrates the magnetic field therein so as to alter the overall magnetic field pattern generated by the magnetic field generating member, wherein the soft magnetic material captures and concentrates the magnetic field therein by having a relatively higher magnetic permeability value than that of its surrounding materials, wherein the magnetic permeability of the soft magnetic material is approximately 100 times or higher than that of its surrounding material; and a keeper barrier layer disposed at least between the magnetic field generating member and the magnetic keeper member, wherein the keeper barrier layer also covers sides of the magnetic keeper member.