# US 8,542,569 B2 · Heat-assisted magnetic recording medium and 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 8,542,569 B2 - Document ID: US8542569B2 - Status: Granted - Kind: B2 - Application number: 13/396,234 - Filed: 2012-02-14 - Published: 2012-08-16 - Granted: 2013-09-24 - Earliest claimed: 2011-02-15 - Assignees: Showa Denko K.K. - Applicants: Tetsuya Kanbe; Kazuya Niwa; Katsuya Hara - Inventors: Tetsuya Kanbe; Kazuya Niwa; Katsuya Hara - Web page: https://patentgrep.com/patent/US8542569B2 ## CPC - G11B 5/737: {Physical structure of underlayer, e.g. texture} - G11B 5/7369: {Two or more non-magnetic underlayers, e.g. seed layers or barrier layers} - G11B 5/7375: {for heat-assisted or thermally-assisted magnetic recording [HAMR, TAMR]} - G11B 2005/0021: {Thermally assisted recording using an auxiliary energy source for heating the recording layer locally to assist the magnetization reversal} - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) ## Abstract A heat-assisted magnetic recording medium includes a substrate, a plurality of foundation layers, and a magnetic layer. The plurality of foundation layers are provided on the substrate and include a first layer containing MnO. The magnetic layer is provided on the plurality of layers and includes an alloy as a main ingredient. The alloy has an L10 structure. ## Claims ### Claim 1 A heat-assisted magnetic recording medium comprising: a substrate; a plurality of foundation layers provided on the substrate and including a first foundation layer containing MnO; and a magnetic layer provided on the plurality of foundation layers and including an alloy as a main ingredient, the alloy having an L10 structure. ### Claim 2 (depends on 1) The heat-assisted magnetic recording medium according to claim 1, wherein the first foundation layer is provided on a second foundation layer consisting of Cr or consisting of an alloy which contains Cr as a main ingredient and at least one of Ti, V, Mo, W, Mn and Ru, the second foundation layer having a body-centered cubic lattice structure. ### Claim 3 (depends on 1) The heat-assisted magnetic recording medium according to claim 1, wherein the first foundation layer is provided on a second foundation layer consisting of an alloy which contains Cr as a main ingredient, at least one of Ti, V, Mo, W, Mn and Ru, and further at least one of B and C, the foundation layer having a body-centered cubic lattice structure. ### Claim 4 (depends on 1) The heat-assisted magnetic recording medium according to claim 1, wherein the first foundation layer is provided on a second foundation layer consisting of Mo, W, Ta, Nb or an alloy which contains at least one of Mo, W, Ta and Nb, the foundation layer having a body-centered cubic lattice structure which has a lattice constant of 0.3 nm or greater. ### Claim 5 (depends on 1) The heat-assisted magnetic recording medium according to claim 1, wherein the first foundation layer is provided on a second foundation layer having a B2 structure and consisting of NiAl or RuAl. ### Claim 6 (depends on 1) The heat-assisted magnetic recording medium according to claim 1, wherein the plurality of foundation layers include a third foundation layer consisting of MgO, and the first foundation layer is provided on the third foundation layer. ### Claim 7 (depends on 6) The heat-assisted magnetic recording medium according to claim 6, wherein the third foundation layer is provided on a second foundation layer consisting of Cr or consisting of an alloy which contains Cr as a main ingredient and at least one of Ti, V, Mo, W, Mn and Ru, the second foundation layer having a body-centered cubic lattice structure. ### Claim 8 (depends on 6) The heat-assisted magnetic recording medium according to claim 6, wherein the third foundation layer is provided on a second foundation layer consisting of an alloy which contains Cr as a main ingredient, at least one of Ti, V, Mo, W, Mn and Ru, and further at least one of B and C, the second foundation layer having a body-centered cubic lattice structure. ### Claim 9 (depends on 6) The heat-assisted magnetic recording medium according to claim 6, wherein the third foundation layer is provided on a second foundation layer consisting of Mo, W, Ta, Nb or an alloy which contains at least one of Mo, W, Ta and Nb, the second foundation layer having a body-centered cubic lattice structure which has a lattice constant of 0.3 nm or greater. ### Claim 10 (depends on 6) The heat-assisted magnetic recording medium according to claim 6, wherein the third foundation layer is provided on a second foundation layer having a B2 structure and consisting of NiAl or RuAl. ### Claim 11 (depends on 1) The heat-assisted magnetic recording medium according to claim 1, wherein the magnetic layer has an L10 structure, and contains an FePt or CoPt alloy as a main ingredient and further contains SiO2, TiO2, Cr2O3, Al2O3, Ta2O5, ZrO2, Y2O3, CeO2, MnO, TiO, ZnO, C or a combination thereof. ### Claim 12 (depends on 1) magnetic storage device comprising: the heat-assisted magnetic recording medium according to claim 1; a magnetic recording medium driving device to rotate the heat-assisted magnetic recording medium; a magnetic head comprising: a laser generator to generate a laser beam; a near-field light generator mounted at an end of the magnetic head and to generate near-field light which heats the heat-assisted magnetic recording medium upon reception of the laser beam; and a waveguide to guide the laser beam to the near-field light generator; a magnetic head driving device to move the magnetic head; and a record regeneration signal processing device.