# US 7,613,033 B2 · Magnetic storage device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,613,033 B2 - Document ID: US7613033B2 - Status: Granted - Kind: B2 - Application number: 11/881,305 - Filed: 2007-07-26 - Published: 2009-01-29 - Granted: 2009-11-03 - Earliest claimed: 2006-07-26 - Assignees: TDK Corporation - Inventors: Keiji Koga; Katsumichi Tagami; Tohru Oiakawa - Web page: https://patentgrep.com/patent/US7613033B2 ## CPC - H10B 61/22: {of the field-effect transistor [FET] type} - B82Y 10/00: Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic - G11C 11/161: {details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell} - G11C 11/1655: {Bit-line or column circuits} - G11C 11/1657: {Word-line or row circuits} - G11C 11/1659: {Cell access} - G11C 11/1673: {Reading or sensing circuits or methods} - G11C 11/1675: {Writing or programming circuits or methods} - H10B: ELECTRONIC MEMORY DEVICES - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES - G11C: STATIC STORES (semiconductor memory devices H10B) ## Abstract A magnetic storage device is provided which has significantly reduced power consumption. In the magnetic storage device, a yoke is arranged so as to circumferentially surround part of a line extending in an arbitrary direction, and a magneto-resistive element to which information can be written by utilizing a magnetic field generated by the line is arranged in the vicinity of the line. In this case, the length of the magnetic path of the yoke is set to 6 μm or less. ## Claims ### Claim 1 A magnetic storage device, comprising: a line; a yoke circumferentially surrounding part of the line in a longitudinal direction; and a magneto-resistive element arranged in the vicinity of the line, to which information can be written by utilizing a magnetic field generated by the line, wherein a length of a magnetic path of the yoke is equal to or less than 6 μm, wherein a length of the yoke in a longitudinal direction of the line is shorter than a length of the line in a longitudinal direction; a gap is formed in part of the yoke in a circumferential direction; and the magneto-resistive element is arranged in or between the gap. ### Claim 2 (depends on 1) The magnetic storage device according to claim 1, wherein the length of the magnetic path of the yoke is equal to or less than 4 μm. ### Claim 3 (depends on 1) The magnetic storage device according to claim 1, wherein a permeability of the yoke is equal to or greater than 300 H/m. ### Claim 4 (depends on 1) The magnetic storage device according to claim 1, a distance between each of end portions of the yoke forming the gap and the magneto-resistive element contained in the gap defined by the end portions of the yoke is equal to or less than 30 nm. ### Claim 5 (depends on 1) The magnetic storage device according to claim 1, wherein: a plurality of storage cells each including the line, the yoke, and the magneto-resistive element are arranged in an array; and each of the storage cells comprises write switching means for controlling electrical conduction of the line. ### Claim 6 (depends on 1) The magnetic storage device according to claim 1, wherein: a plurality of storage cells each including the line, the yoke, and the magneto-resistive element are arranged in an array; each of the storage cells comprises write switching means for controlling electrical conduction of the line; and each of the storage cells further comprises: a read line for allowing a current to pass though the magneto-resistive element; and read switching means for controlling electrical conduction of the read line. ### Claim 7 (depends on 1) The magnetic storage device according to claim 1, wherein: the length of the magnetic path of the yoke is equal to or less than 4 μm; and a permeability of the yoke is equal to or greater than 300 H/m. ### Claim 8 (depends on 1) The magnetic storage device according to claim 1, wherein: the length of the magnetic path of the yoke is equal to or less than 4 μm. ### Claim 9 (depends on 1) The magnetic storage device according to claim 1, wherein: a permeability of the yoke is equal to or greater than 300 H/m. ### Claim 10 (depends on 1) The magnetic storage device according to claim 1, wherein: the length of the magnetic path of the yoke is equal to or less than 4 μm; a permeability of the yoke is equal to or greater than 300 H/m; and a distance between each of end portions of the yoke forming the gap and the magneto-resistive element contained in the gap defined by the end portions of the yoke is equal to or less than 30 nm. ### Claim 11 (depends on 1) The magnetic storage device according to claim 1, wherein: the length of the magnetic path of the yoke is equal to or less than 4 μm; a plurality of storage cells each including the line, the yoke, and the magneto-resistive element are arranged in an array; and each of the storage cells comprises write switching means for controlling electrical conduction of the line. ### Claim 12 (depends on 1) The magnetic storage device according to claim 1, wherein: a permeability of the yoke is equal to or greater than 300 H/m; a plurality of storage cells each including the line, the yoke, and the magneto-resistive element are arranged in an array; and each of the storage cells comprises write switching means for controlling electrical conduction of the line. ### Claim 13 (depends on 1) The magnetic storage device according to claim 1, wherein: a plurality of storage cells each including the line, the yoke, and the magneto-resistive element are arranged in an array; and each of the storage cells comprises write switching means for controlling electrical conduction of the line. ### Claim 14 (depends on 1) The magnetic storage device according to claim 1, wherein: a distance between each of end portions of the yoke forming the gap and the magneto-resistive element contained in the gap defined by the end portions of the yoke is equal to or less than 30 nm; a plurality of storage cells each including the line, the yoke, and the magneto-resistive element are arranged in an array; and each of the storage cells comprises write switching means for controlling electrical conduction of the line. ### Claim 15 (depends on 1) The magnetic storage device according to claim 1, wherein: a distance between each of end portions of the yoke forming the gap and the magneto-resistive element contained in the gap defined by the end portions of the yoke is equal to or less than 30 nm; a plurality of storage cells each including the line, the yoke, and the magneto-resistive element are arranged in an array; each of the storage cells comprises write switching means for controlling electrical conduction of the line; and each of the storage cells further comprises: a read line for allowing a current to pass through the magneto-resistive element; and read switching means for controlling electrical conduction of the read line. ### Claim 16 (depends on 1) The magnetic storage device according to claim 1 wherein the yoke comprises: an element side yoke which is arranged near the line on the magneto-resistive element side; and a counter side yoke which is arranged near the line on the side opposite to the magneto-resistive element side; and the thickness of the counter-side yoke is made larger than the thickness of the element-side yoke; and wherein a length of the element-side yoke and the counter-side yoke in a longitudinal direction of the line is shorter than a length of the line in a longitudinal direction. ### Claim 17 (depends on 1) The magnetic storage device according to claim 1, wherein the yoke comprises: an element side yoke which is arranged near the line on the magneto-resistive element side; and a counter side yoke which is arranged near the line on the side opposite the magneto-resistive element side: and the counter-side yoke further comprises: a top region located above the line; and an inclined regions each positioned on one of the end sides of the top region; and wherein a length of the element-side yoke and the counter-side yoke in a longitudinal direction of the line is shorter than a length of the line in a longitudinal direction. ### Claim 18 (depends on 1) The magnetic storage device according to claim 1 wherein the yoke comprises: an element side yoke which is arranged near the line on the magneto-resistive element side; and a counter side yoke which is arranged near the line on the side opposite the magneto-resistive element side; and the counter-side yoke further comprises: a top region located above the line; and an inclined regions each positioned on one of the end sides of the top region; and the inclined regions and the top region are integrally deposited in a series of processes; and a length of the element-side yoke and the counter-side yoke in a longitudinal direction of the line is shorter than a length of the line in a longitudinal direction. ### Claim 19 (depends on 16) The magnetic storage device according to claim 16 wherein a length of the element side yoke is equal to a length of the counter side yoke in a longitudinal direction of the line. ### Claim 20 (depends on 1) The magnetic storage device according to claim 1 wherein a length of the yoke in a longitudinal direction of the line is from 0.45 to 0.8 μm.