Patents by Inventor Abebe Hailu

Abebe Hailu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9734857
    Abstract: A stack including a crystallographic orientation interlayer, a magnetic zero layer disposed on the interlayer, and a magnetic recording layer disposed on the magnetic zero layer is disclosed. The magnetic zero layer is non-magnetic or has a saturation magnetic flux density (Bs) less than about 100 emu/cc. The magnetic zero layer and the magnetic layer include grains surrounded by a non-magnetic segregant. The magnetic zero layer provides a coherent interface between the interlayer and the magnetic layer with a lattice mismatch less than about 4%.
    Type: Grant
    Filed: July 24, 2015
    Date of Patent: August 15, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Jai-Young Kim, Thomas P. Nolan, Kyongha Kang, Shoutao Wang, Vincent D. Nguyen, Abebe Hailu, Charles C. Chen
  • Patent number: 9311948
    Abstract: A perpendicular magnetic recording layer of a magnetic recording medium includes a plurality of bit-patterned magnetic islands, wherein each of the plurality of islands overlay a soft magnetic under-layer. Each of the magnetic islands includes a first magnetic sub-layer adjacent a second magnetic sub-layer, wherein the first sub-layer has a relatively high magnetic anisotropy that is greater than a magnetic anisotropy of the second sub-layer. The magnetic recording layer further includes a third sub-layer, which extends to connect each of the plurality of islands. The third sub-layer may have a magnetic anisotropy that is less than that of the second sub-layer of each of the magnetic islands and/or may serve as an interlayer, extending between the first sub-layer and the soft magnetic under-layer of the recording medium, and having a structure to help to produce the greater anisotropy first magnetic sub-layer.
    Type: Grant
    Filed: December 31, 2008
    Date of Patent: April 12, 2016
    Assignee: Seagate Technology LLC
    Inventors: Erol Girt, Dieter K. Weller, Alexander Y. Dobin, Bogdan F. Valcu, Thomas F. Ambrose, Yingguo Peng, Yukiko A. Kubota, Abebe Hailu
  • Publication number: 20150332721
    Abstract: A stack including a crystallographic orientation interlayer, a magnetic zero layer disposed on the interlayer, and a magnetic recording layer disposed on the magnetic zero layer is disclosed. The magnetic zero layer is non-magnetic or has a saturation magnetic flux density (Bs) less than about 100 emu/cc. The magnetic zero layer and the magnetic layer include grains surrounded by a non-magnetic segregant. The magnetic zero layer provides a coherent interface between the interlayer and the magnetic layer with a lattice mismatch less than about 4%.
    Type: Application
    Filed: July 24, 2015
    Publication date: November 19, 2015
    Inventors: Jai-Young Kim, Thomas P. Nolan, Kyongha Kang, Shoutao Wang, Vincent D. Nguyen, Abebe Hailu, Charles C. Chen
  • Patent number: 9190095
    Abstract: An apparatus and method are provided for improving perpendicular magnetic recording media. The present invention provides media, and a method of fabricating media in a cost-effective manner, with a reduced ruthenium (Ru) content interlayer structure, while meeting media performance requirements. A perpendicular magnetic recording medium is provided comprising a non-magnetic substrate having a surface, and a layer stack situated on the substrate surface. The layer stack comprises, in overlying sequence from the substrate surface a magnetically soft underlayer; an amorphous or crystalline, non-magnetic seed layer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material situated on the underlayer; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer situated on the interlayer structure.
    Type: Grant
    Filed: January 20, 2014
    Date of Patent: November 17, 2015
    Assignee: Seagate Technology LLC
    Inventors: Shoutao Wang, Weilu Xu, Chung-hee Chang, Xiaoguang Ma, Mark Johnson, Abebe Hailu, Charles Chen
  • Patent number: 9093101
    Abstract: A stack including a crystallographic orientation interlayer, a magnetic zero layer disposed on the interlayer, and a magnetic recording layer disposed on the magnetic zero layer is disclosed. The magnetic zero layer is non-magnetic or has a saturation magnetic flux density (Bs) less than about 100 emu/cc. The magnetic zero layer and the magnetic layer include grains surrounded by a non-magnetic segregant. The magnetic zero layer provides a coherent interface between the interlayer and the magnetic layer with a lattice mismatch less than about 4%.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: July 28, 2015
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Jai-Young Kim, Thomas P. Nolan, Kyongha Kang, Shoutao Wang, Vincent D. Nguyen, Abebe Hailu, Charles C. Chen
  • Publication number: 20140186658
    Abstract: An apparatus and method are provided for improving perpendicular magnetic recording media. The present invention provides media, and a method of fabricating media in a cost-effective manner, with a reduced ruthenium (Ru) content interlayer structure, while meeting media performance requirements. A perpendicular magnetic recording medium is provided comprising a non-magnetic substrate having a surface, and a layer stack situated on the substrate surface. The layer stack comprises, in overlying sequence from the substrate surface a magnetically soft underlayer; an amorphous or crystalline, non-magnetic seed layer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material situated on the underlayer; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer situated on the interlayer structure.
    Type: Application
    Filed: January 20, 2014
    Publication date: July 3, 2014
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Shoutao Wang, Weilu Xu, Chung-hee Chang, Xiaoguang Ma, Mark Johnson, Abebe Hailu, Charles Chen
  • Patent number: 8696874
    Abstract: An apparatus and method are provided for improving perpendicular magnetic recording media. The present invention provides media, and a method of fabricating media in a cost-effective manner, with a reduced ruthenium (Ru) content interlayer structure, while meeting media performance requirements. A perpendicular magnetic recording medium is provided comprising a non-magnetic substrate having a surface, and a layer stack situated on the substrate surface. The layer stack comprises, in overlying sequence from the substrate surface a magnetically soft underlayer; an amorphous or crystalline, non-magnetic seed layer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material situated on the underlayer; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer situated on the interlayer structure.
    Type: Grant
    Filed: February 7, 2012
    Date of Patent: April 15, 2014
    Assignee: Seagate Technology LLC
    Inventors: Shoutao Wang, Weilu Xu, Chunghee Chang, Xiaoguang Ma, Mark Johnson, Abebe Hailu, Charles Chen
  • Patent number: 8685547
    Abstract: Aspects are directed to recording media with enhanced magnetic properties for improved writability. Examples can be included or related to methods, systems and components that allow for improved writability while reducing defects so as to obtain uniform magnetic properties such as uniformly high anisotropy and narrow switching field distribution. Some examples include a recording medium with an exchange tuning layer inserted between the hard layer and the soft, semi-soft or thin semi-hard layer so as to maximize the writability improvement of the media. Preferably, the exchange tuning layer is granular and reduces or optimizes the vertical coupling between the hard layer and the soft, semi-soft or semi-hard layer of a magnetic recording or storing device.
    Type: Grant
    Filed: February 19, 2009
    Date of Patent: April 1, 2014
    Assignee: Seagate Technology LLC
    Inventors: Bo Bian, Shoutao Wang, Weilu Xu, Abebe Hailu, Miaogen Lu, Charles C. Chen, Thomas Patrick Nolan, Alexander Yulievich Dobin
  • Publication number: 20130052485
    Abstract: A perpendicular magnetic recording stack with a dual continuous layer and a method of manufacturing the same. The perpendicular magnetic recording stack includes a substrate, one or more magnetic granular recording layers, and a dual continuous layer having first and second continuous layers. The first continuous layer, disposed between the second continuous layer and the magnetic granular recording layers, has an intermediate lateral exchange coupling, which is higher than the lateral exchange coupling of the magnetic granular layers. The second continuous layer has a higher lateral exchange coupling than the first continuous layer.
    Type: Application
    Filed: August 25, 2011
    Publication date: February 28, 2013
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Zhong Wu, Li Tang, Shoutao Wang, Abebe Hailu
  • Publication number: 20120219827
    Abstract: A stack including a crystallographic orientation interlayer, a magnetic zero layer disposed on the interlayer, and a magnetic recording layer disposed on the magnetic zero layer is disclosed. The magnetic zero layer is non-magnetic or has a saturation magnetic flux density (Bs) less than about 100 emu/cc. The magnetic zero layer and the magnetic layer include grains surrounded by a non-magnetic segregant. The magnetic zero layer provides a coherent interface between the interlayer and the magnetic layer with a lattice mismatch less than about 4%.
    Type: Application
    Filed: February 28, 2011
    Publication date: August 30, 2012
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Jai-Young Kim, Thomas P. Nolan, Kyongha Kang, Shoutao Wang, Vincent D. Nguyen, Abebe Hailu, Charles C. Chen
  • Publication number: 20120141836
    Abstract: An apparatus and method are provided for improving perpendicular magnetic recording media. The present invention provides media, and a method of fabricating media in a cost-effective manner, with a reduced ruthenium (Ru) content interlayer structure, while meeting media performance requirements. A perpendicular magnetic recording medium is provided comprising a non-magnetic substrate having a surface, and a layer stack situated on the substrate surface. The layer stack comprises, in overlying sequence from the substrate surface a magnetically soft underlayer; an amorphous or crystalline, non-magnetic seed layer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material situated on the underlayer; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer situated on the interlayer structure.
    Type: Application
    Filed: February 7, 2012
    Publication date: June 7, 2012
    Applicant: Seagate Technology LLC
    Inventors: Shoutao Wang, Weilu Xu, Chunghee Chang, Xiaoguang Ma, Mark Johnson, Abebe Hailu, Charles Chen
  • Patent number: 8110299
    Abstract: An apparatus and method are provided for improving perpendicular magnetic recording media. The present invention provides media, and a method of fabricating media in a cost-effective manner, with a reduced ruthenium (Ru) content interlayer structure, while meeting media performance requirements. A perpendicular magnetic recording medium is provided comprising a non-magnetic substrate having a surface, and a layer stack situated on the substrate surface. The layer stack comprises, in overlying sequence from the substrate surface a magnetically soft underlayer; an amorphous or crystalline, non-magnetic seed layer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material situated on the underlayer; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer situated on the interlayer structure.
    Type: Grant
    Filed: February 27, 2009
    Date of Patent: February 7, 2012
    Assignee: Seagate Technology LLC
    Inventors: Shoutao Wang, Weilu Xu, Chunghee Chang, Xiaoguang Ma, Mark Johnson, Abebe Hailu, Charles Chen
  • Patent number: 8025993
    Abstract: A perpendicular magnetic recording medium comprises a layer stack formed over a surface of a non-magnetic substrate, and comprising, in overlying sequence from the surface: a magnetically soft underlayer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material formed thereon; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer on the interlayer structure; wherein the interlayer structure is a triple-layer stacked structure comprising: a first interlayer of a first non-magnetic material proximal the magnetically soft underlayer and containing Ru; a second interlayer of a second non-magnetic material in overlying contact with the first interlayer and not containing Ru; and a third interlayer of a third non-magnetic material in overlying contact with the second interlayer and containing Ru.
    Type: Grant
    Filed: February 23, 2007
    Date of Patent: September 27, 2011
    Assignee: Seagate Technology LLC
    Inventors: Abebe Hailu, Weilu Xu, Xiaoguang Ma, Chung-Hee Chang, Shoutao Wang, Charles C. Chen
  • Publication number: 20100221580
    Abstract: An apparatus and method are provided for improving perpendicular magnetic recording media. The present invention provides media, and a method of fabricating media in a cost-effective manner, with a reduced ruthenium (Ru) content interlayer structure, while meeting media performance requirements. A perpendicular magnetic recording medium is provided comprising a non-magnetic substrate having a surface, and a layer stack situated on the substrate surface. The layer stack comprises, in overlying sequence from the substrate surface a magnetically soft underlayer; an amorphous or crystalline, non-magnetic seed layer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material situated on the underlayer; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer situated on the interlayer structure.
    Type: Application
    Filed: February 27, 2009
    Publication date: September 2, 2010
    Inventors: Shoutao Wang, Weilu Xu, Chunghee Chang, Xiaoguang Ma, Mark Johnson, Abebe Hailu, Charles Chen
  • Publication number: 20100209737
    Abstract: Aspects are directed to recording media with enhanced magnetic properties for improved writability. Examples can be included or related to methods, systems and components that allow for improved writability while reducing defects so as to obtain uniform magnetic properties such as uniformly high anisotropy and narrow switching field distribution. Some examples include a recording medium with an exchange tuning layer inserted between the hard layer and the soft, semi-soft or thin semi-hard layer so as to maximize the writability improvement of the media. Preferably, the exchange tuning layer is granular and reduces or optimizes the vertical coupling between the hard layer and the soft, semi-soft or semi-hard layer of a magnetic recording or storing device.
    Type: Application
    Filed: February 19, 2009
    Publication date: August 19, 2010
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Bo Bian, Shoutao Wang, Weilu Xu, Abebe Hailu, Miaogen Lu, Charles C. Chen, Thomas Patrick Nolan, Alexander Yulievich Dobin
  • Publication number: 20100165508
    Abstract: A perpendicular magnetic recording layer of a magnetic recording medium includes a plurality of bit-patterned magnetic islands, wherein each of the plurality of islands overlay a soft magnetic under-layer. Each of the magnetic islands includes a first magnetic sub-layer adjacent a second magnetic sub-layer, wherein the first sub-layer has a relatively high magnetic anisotropy that is greater than a magnetic anisotropy of the second sub-layer. The magnetic recording layer further includes a third sub-layer, which extends to connect each of the plurality of islands. The third sub-layer may have a magnetic anisotropy that is less than that of the second sub-layer of each of the magnetic islands and/or may serve as an interlayer, extending between the first sub-layer and the soft magnetic under-layer of the recording medium, and having a structure to help to produce the greater anisotropy first magnetic sub-layer.
    Type: Application
    Filed: December 31, 2008
    Publication date: July 1, 2010
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Erol Girt, Dieter K. Weller, Alexander Y. Dobin, Bogdan F. Valcu, Thomas F. Ambrose, Yingguo Peng, Yukiko A. Kubota, Abebe Hailu
  • Publication number: 20090211898
    Abstract: CoCrPtB is a conventional material used in some of the layers of a thin film magnetic media structure used for recording data in data storage devices such as hard drives. Typically the CoCrPtB layers used for magnetic media have high Cr and low B in bottom magnetic layers and low Cr and high B in top magnetic layers. In accordance with one embodiment of this invention and to improve media electrical performance, fifth elements, such as Ta, Nb and Hf, etc. were added to the CoCrPtB materials, resulting in CoCrPtB-X, to enhance the grain segregation. The five element CoCrPtB-X layers were deposited using a pulsed direct current sputter technique instead of conventional direct current sputtering techniques. The resulting magnetic media structure having CoCrPtB-X alloy layers exhibits an increase in coercivity Hc and improvement in recording performance.
    Type: Application
    Filed: February 24, 2009
    Publication date: August 27, 2009
    Applicant: Seagate Technology LLC
    Inventors: Charles Changqing Chen, Thanh Thien Ha, Abebe Hailu, Taesun Ernest Kim, Mariana Rodica Munteanu, Steve Kuo-Hsing Hwang
  • Patent number: 7504166
    Abstract: CoCrPtB is a conventional material used in some of the layers of a thin film magnetic media structure used for recording data in data storage devices such as hard drives. Typically the CoCrPtB layers used for magnetic media have high Cr and low B in bottom magnetic layers and low Cr and high B in top magnetic layers. In accordance with one embodiment of this invention and to improve media electrical performance, fifth elements, such as Ta, Nb and Hf, etc. were added to the CoCrPtB materials, resulting in CoCrPtB—X, to enhance the grain segregation. The five element CoCrPtB—X layers were deposited using a pulsed direct current sputter technique instead of conventional direct current sputtering techniques. The resulting magnetic media structure having CoCrPtB—X alloy layers exhibits an increase in coercivity Hc and improvement in recording performance.
    Type: Grant
    Filed: May 27, 2004
    Date of Patent: March 17, 2009
    Assignee: Seagate Technology LLC
    Inventors: Charles Changqing Chen, Thanh Thien Ha, Abebe Hailu, Taesun Ernest Kim, Mariana Rodica Munteanu, Steve Kuo-Hsing Hwang
  • Publication number: 20080213628
    Abstract: A perpendicular magnetic recording medium comprising a substrate, an underlayer, a Ta-containing seedlayer, a magnetic layer, wherein the underlayer comprises a soft magnetic material and the Ta-containing seedlayer is between the underlayer and the magnetic layer, and a process for improving corrosion resistance of the recording medium and for manufacturing the recording medium are disclosed.
    Type: Application
    Filed: March 1, 2007
    Publication date: September 4, 2008
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Abebe Hailu, Raj Thangaraj, Miaogen Lu, Qixu Chen, Michael Z. Wu, Mariana R. Munteanu, Kuo-Hsing Hwang
  • Publication number: 20080204933
    Abstract: A perpendicular magnetic recording medium comprises a layer stack formed over a surface of a non-magnetic substrate, and comprising, in overlying sequence from the surface: a magnetically soft underlayer; an interlayer structure for crystallographically orienting a layer of a perpendicular magnetic recording material formed thereon; and at least one crystallographically oriented, magnetically hard, perpendicular magnetic recording layer on the interlayer structure; wherein the interlayer structure is a triple-layer stacked structure comprising: a first interlayer of a first non-magnetic material proximal the magnetically soft underlayer and containing Ru; a second interlayer of a second non-magnetic material in overlying contact with the first interlayer and not containing Ru; and a third interlayer of a third non-magnetic material in overlying contact with the second interlayer and containing Ru.
    Type: Application
    Filed: February 23, 2007
    Publication date: August 28, 2008
    Inventors: Abebe Hailu, Weilu Xu, Xiaoguang Ma, Chung-Hee Chang, Shoutao Wang, Charles C. Chen