Patents by Inventor Naoya Hasegawa

Naoya Hasegawa 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: 7800866
    Abstract: A magnetic sensing element is described, including a multilayer film including a pinned magnetic layer, a free magnetic layer disposed on the pinned magnetic layer with a nonmagnetic layer therebetween, wherein a current flows perpendicular to the surfaces of the individual layers of the multilayer film. The nonmagnetic layer is composed of Cu and has a face-centered cubic lattice crystal structure in which the {111} planes are preferentially oriented in a direction parallel to the surfaces of the layer. At least one of the pinned magnetic layer and the free magnetic layer includes a Co2Mn(Ge1-xSnx) alloy layer, the subscript x satisfying the range of 0.2?x?0.8; and the Co2Mn(Ge1-xSnx) alloy layer has a body-centered cubic lattice crystal structure in which the {110} planes are preferentially oriented in a direction parallel to the surfaces of the layer.
    Type: Grant
    Filed: March 22, 2006
    Date of Patent: September 21, 2010
    Assignee: TDK Corporation
    Inventors: Yosuke Ide, Masamichi Saito, Masahiko Ishizone, Naoya Hasegawa
  • Patent number: 7800867
    Abstract: A CPP giant magnetoresistive head includes lower and upper shield layers, and a giant magnetoresistive element disposed between the upper and lower shield layers and including a pinned magnetic layer, a free magnetic layer and a nonmagnetic layer disposed between the pinned magnetic layer and the free magnetic layer. In the CPP giant magnetoresistive head, the pinned magnetic layer extends to the rear of the nonmagnetic layer and the free magnetic layer in the height direction, and the dimension of the pinned magnetic layer in the height direction is larger than that in the track width direction. Also, the pinned magnetic layer comprises a magnetic material having a positive magnetostriction constant or a magnetic material having high coercive force, and the end of the pinned magnetic layer is exposed at a surface facing a recording medium.
    Type: Grant
    Filed: August 27, 2009
    Date of Patent: September 21, 2010
    Assignee: TDK Corporation
    Inventors: Masamichi Saito, Yoshihiro Nishiyama, Yosuke Ide, Eiji Umetsu, Naoya Hasegawa, Yasuo Hayakawa
  • Patent number: 7787221
    Abstract: A first pinned magnetic sublayer 4a has a multilayered structure including a first insertion subsublayer disposed between a lower ferromagnetic subsublayer and an upper ferromagnetic subsublayer. The first insertion subsublayer has an average thickness exceeding 3 ? and 6 ? or less. This results in an interlayer coupling magnetic field Hin lower than a known art while RA and the rate of resistance change (?R/R) substantially identical to those of the known structure are maintained.
    Type: Grant
    Filed: February 6, 2007
    Date of Patent: August 31, 2010
    Assignee: Alps Electric Co., Ltd.
    Inventors: Ryo Nakabayashi, Kazumasa Nishimura, Yosuke Ide, Yoshihiro Nishiyama, Hidekazu Kobayashi, Masamichi Saito, Naoya Hasegawa
  • Patent number: 7760473
    Abstract: An advantage of the application is to provide a magnetoresistance element capable of increasing a plateau magnetic field Hp1 while maintaining high ?RA. A magnetic layer 4c1 adjacent to a non-magnetic material layer 5 in a second fixed magnetic layer 4c constituting the fixed magnetic layer 4 is formed of a first Heusler-alloy layer represented by Co2x(Mn(1-z)Fez)x?y (where the element ? is any one element of 3B group, 4B group, and 5B group, x and y all are in the unit of at %, 3x+y=100 at %). Additionally, the content y is in the range of 20 to 30 at % and a Fe ratio z in MnFe is in the range of 0.2 to 0.8. Accordingly, the plateau magnetic field Hp1 may increase while maintaining high ?RA.
    Type: Grant
    Filed: February 16, 2007
    Date of Patent: July 20, 2010
    Assignee: TDK Corporation
    Inventors: Yosuke Ide, Ryo Nakabayashi, Masamichi Saito, Naoya Hasegawa
  • Patent number: 7738218
    Abstract: A magnetic detection element capable of maintaining the ?RA at a high level and reducing the magnetostriction by improving a material for a free magnetic layer, as well as a method for manufacturing the same, is provided. The free magnetic layer includes a laminate composed of a CoMnX alloy layer formed from a metal compound represented by a compositional formula CoaMnbXc (where X represents at least one of Ge, Ga, In, Si, Pb, Zn, and Sb and a+b+c=100 atomic percent) and a CoMnZ alloy layer formed from a metal compound represented by a compositional formula CodMneZf (where Z represents at least one of Sn and Al and d+e+f=100 atomic percent). In this manner, the magnetostriction of the free magnetic layer can be reduced.
    Type: Grant
    Filed: May 17, 2006
    Date of Patent: June 15, 2010
    Assignee: TDK Corporation
    Inventors: Yosuke Ide, Masamichi Saito, Masahiko Ishizone, Naoya Hasegawa
  • Patent number: 7724481
    Abstract: A magnetic sensing element is provided. A free magnetic layer has a three-layer structure including CoMn? sublayers each composed of a metal compound represented by the formula: Co2xMnx?y. The ? contains an element ? and Sb, the element ? being at least one element selected from Ge, Ga, In, Si, Pb, Zn, Sn, and Al. The concentration x and the concentration y are each represented in terms of atomic percent and satisfy the equation: 3x+y=100 atomic percent. One of the CoMn? sublayers is in contact with a lower nonmagnetic material layer. The other CoMn? sublayer is in contact with upper nonmagnetic material layer. As a result, it is possible to achieve a high ?RA and a lower interlayer coupling magnetic field Hin compared with the known art.
    Type: Grant
    Filed: August 15, 2006
    Date of Patent: May 25, 2010
    Assignee: TDK Corporation
    Inventors: Yosuke Ide, Masamichi Saito, Masahiko Ishizone, Kazumasa Nishimura, Naoya Hasegawa
  • Publication number: 20100055452
    Abstract: A tunneling magnetic sensing element includes a laminate in which an underlayer, a seed layer, an antiferromagnetic layer, a pinned magnetic layer, an insulating barrier layer, and a free magnetic layer are laminated in order from below. The insulating barrier layer is made of Mg—O. The underlayer is made of Ti, and the seed layer is made of one selected from a group consisting of Ni—Fe—Cr and Ru.
    Type: Application
    Filed: November 10, 2009
    Publication date: March 4, 2010
    Applicant: Alps Electric Co., Ltd.
    Inventors: Kazumasa Nishimura, Masamichi Saito, Yosuke Ide, Ryo Nakabayashi, Yoshihiro Nishiyama, Hidekazu Kobayashi, Naoya Hasegawa
  • Publication number: 20100055501
    Abstract: A tunneling magnetic sensing element includes a laminate in which a pinned magnetic layer having a magnetization direction pinned, an insulating barrier layer, and a free magnetic layer having a magnetization direction variable with an external magnetic field are laminated in order from below. The insulating barrier layer is made of Mg—O. The free magnetic layer has a soft magnetic layer and an enhanced layer disposed between the soft magnetic layer and the insulating barrier layer to have a spin polarization ratio higher than the soft magnetic layer. An insertion magnetic layer made of one selected from Co—Fe—B, Co—B, Fe—B, and Co—Fe is inserted into the soft magnetic layer in a direction parallel to the interface of each layer constituting the laminate, and the soft magnetic layer is divided into multiple layers in a thickness direction through the insertion magnetic layer.
    Type: Application
    Filed: November 12, 2009
    Publication date: March 4, 2010
    Applicant: Alps Electric Co., Ltd.
    Inventors: Kazumasa Nishimura, Hidekazu Kobayashi, Masamichi Saito, Yosuke Ide, Ryo Nakabayashi, Yoshihiro Nishiyama, Akio Hanada, Naoya Hasegawa
  • Patent number: 7643254
    Abstract: A free magnetic layer of a tunnel-effect type magnetic sensor is formed on an insulating barrier layer made of Mg—O, and the free magnetic layer includes an enhancement layer, a first soft magnetic layer, a non-magnetic metal layer, and a second soft magnetic layer, which are laminated in that order from the bottom. For example, the enhancement layer is formed of Co—Fe, the first and the second soft magnetic layers are formed of Ni—Fe, and the non-magnetic metal layer is formed of Ta. The average thickness of the first soft magnetic layer is formed in the range of 5 to 60 ?. Accordingly, a high resistance change rate (?R/R) can be obtained.
    Type: Grant
    Filed: February 6, 2007
    Date of Patent: January 5, 2010
    Assignee: Alps Electric Co., Ltd.
    Inventors: Yosuke Ide, Naoya Hasegawa, Masamichi Saito, Ryo Nakabayashi, Yoshihiro Nishiyama, Kazumasa Nishimura, Hidekazu Kobayashi
  • Publication number: 20090316308
    Abstract: A CPP giant magnetoresistive head includes lower and upper shield layers, and a giant magnetoresistive element disposed between the upper and lower shield layers and including a pinned magnetic layer, a free magnetic layer and a nonmagnetic layer disposed between the pinned magnetic layer and the free magnetic layer. In the CPP giant magnetoresistive head, the pinned magnetic layer extends to the rear of the nonmagnetic layer and the free magnetic layer in the height direction, and the dimension of the pinned magnetic layer in the height direction is larger than that in the track width direction. Also, the pinned magnetic layer comprises a magnetic material having a positive magnetostriction constant or a magnetic material having high coercive force, and the end of the pinned magnetic layer is exposed at a surface facing a recording medium.
    Type: Application
    Filed: August 27, 2009
    Publication date: December 24, 2009
    Inventors: Masamichi Saito, Yoshihiro Nishiyama, Yosuke Ide, Eiji Umetsu, Naoya Hasegawa, Yasuo Hayakawa
  • Patent number: 7616410
    Abstract: There are provided a magnetic detecting element capable of maintaining large ?RA and of reducing magnetostriction by improving a material forming a free magnetic layer, and a method of manufacturing the same. An NiFeX alloy layer is formed in a free magnetic layer. For example, the element X is Cu. The NiFeX alloy layer formed in the free magnetic layer makes it possible to maintain large ?RA and to more reduce the magnetostriction of the free magnetic layer, compared with a structure in which an NiFe alloy layer is formed in the free magnetic layer.
    Type: Grant
    Filed: February 21, 2006
    Date of Patent: November 10, 2009
    Assignee: TDK Corporation
    Inventors: Masahiko Ishizone, Yosuke Ide, Masamichi Saito, Naoya Hasegawa
  • Patent number: 7609489
    Abstract: A magnetic sensor comprising: a multilayer film which has a pinned magnetic layer, the magnetization thereof being pinned in one direction, and a free magnetic layer formed on the pinned magnetic layer with a nonmagnetic material layer provided therebetween, in which current is allowed to flow in a direction perpendicular to the surfaces of the layers forming the multilayer film, wherein the pinned magnetic layer has a NiaFeb alloy layer (where a and b each indicate atomic percent, and 0<a?25 and a+b=100 are satisfied).
    Type: Grant
    Filed: February 28, 2006
    Date of Patent: October 27, 2009
    Assignee: TDK Corporation
    Inventors: Yosuke Ide, Masamichi Saito, Masahiko Ishizone, Naoya Hasegawa
  • Patent number: 7599155
    Abstract: A CPP giant magnetoresistive head includes lower and upper shield layers, and a giant magnetoresistive element disposed between the upper and lower shield layers and including a pinned magnetic layer, a free magnetic layer and a nonmagnetic layer disposed between the pinned magnetic layer and the free magnetic layer. In the CPP giant magnetoresistive head, the pinned magnetic layer extends to the rear of the nonmagnetic layer and the free magnetic layer in the height direction, and the dimension of the pinned magnetic layer in the height direction is larger than that in the track width direction. Also, the pinned magnetic layer comprises a magnetic material having a positive magnetostriction constant or a magnetic material having high coercive force, and the end of the pinned magnetic layer is exposed at a surface facing a recording medium.
    Type: Grant
    Filed: April 13, 2004
    Date of Patent: October 6, 2009
    Assignee: TDK Corporation
    Inventors: Masamichi Saito, Yoshihiro Nishiyama, Yosuke Ide, Eiji Umetsu, Naoya Hasegawa, Yasuo Hayakawa
  • Patent number: 7567412
    Abstract: A magnetic sensing element includes a free magnetic layer having a three-layer structure including a first enhancement layer in contact with a nonmagnetic material layer, a second enhancement layer, and a low-coercivity layer. The second enhancement layer has a lower magnetostriction coefficient ? than the first enhancement layer. If such an enhancement layer having a bilayer structure is used, rather than a known monolayer structure, and the second enhancement layer has a lower magnetostriction coefficient ? than the first enhancement layer, the rate of change in magnetoresistance of the magnetic sensing element can be increased with no increase in the magnetostriction coefficient ? of the free magnetic layer.
    Type: Grant
    Filed: October 26, 2005
    Date of Patent: July 28, 2009
    Assignee: Alps Electric Co., Ltd.
    Inventors: Ryo Nakabayashi, Eiji Umetsu, Kazuaki Ikarashi, Fumihito Koike, Naoya Hasegawa
  • Patent number: 7567413
    Abstract: There is provided a magnetic detecting element by devising a configuration of a free magnetic layer or a pinned magnetic layer, and a method of manufacturing a magnetic detecting element. The free magnetic layer is formed to have a three-layered structure of a CoMnZ alloy layer, a CoMnX alloy layer, and a CoMnZ alloy layer. The CoMnX alloy layer is formed of a metal compound whose compositional formula is represented by CoaMnbXc (X is one or more elements selected from a group of Ge, Sn, Ga, and Sb, a, b, and c are atomic percent, and a+b+c=100 atomic percent). The CoMnZ alloy layer is formed of a metal compound whose compositional formula is represented by CodMneZf (Z is Al or Si, d, e, and f are atomic percent, and d+e+f=100 atomic percent).
    Type: Grant
    Filed: April 3, 2006
    Date of Patent: July 28, 2009
    Assignee: TDK Corporation
    Inventors: Yosuke Ide, Masamichi Saito, Masahiko Ishizone, Naoya Hasegawa
  • Patent number: 7564661
    Abstract: A magnetic sensing element which allows a high reproduction output and reduction in asymmetry of reproduction waveform to become mutually compatible, as well as a method for manufacturing the same, is provided. In the inside of a second pinned magnetic layer and a free magnetic layer, the atomic percentage of an element Z is decreased in a region close to a non-magnetic material layer. Consequently, the ferromagnetic coupling magnetic field due to magnetostatic coupling (topological coupling) between the pinned magnetic layer and the free magnetic layer can be reduced. At the same time, in a region at a distance from the non-magnetic material layer, the atomic percentage of an element Z is increased, a spin-dependent bulk scattering coefficient is increased, and a product of the amount of change in magnetic resistance and the element area of the magnetic sensing element can be maintained at a high level.
    Type: Grant
    Filed: February 13, 2006
    Date of Patent: July 21, 2009
    Assignee: TDK Corporation
    Inventors: Yosuke Ide, Masamichi Saito, Masahiko Ishizone, Naoya Hasegawa
  • Patent number: 7558029
    Abstract: There is provided a magnetic detecting element having a large ?RA. A free magnetic layer has a three layer structure in which a CoFe layer, an NiaFeb alloy layer (where a and b are represented by at %, 0?a?25, and a+b=100), and a CoFe layer are laminated from the bottom. If the at % of Ni in an NiFe alloy that exists in the free magnetic layer is in this range, a spin-dependent bulk scattering coefficient ? increases, and the product ?RA of the resistance variation of the magnetic detecting element and the area of the element can be made increased.
    Type: Grant
    Filed: February 27, 2006
    Date of Patent: July 7, 2009
    Assignee: TDK Corporation
    Inventors: Yosuke Ide, Masamichi Saito, Masahiko Ishizone, Naoya Hasegawa
  • Patent number: 7554776
    Abstract: A CPP magnetic sensing element is provided which may exhibit a large value of ?RA (the product of the resistance variation ?R and area A of the magnetic sensing element). The magnetic sensing element includes a free magnetic layer and a pinned magnetic layer. At least one of these layers has a (Co0.67Fe0.33)100-aZa alloy layer, wherein Z may represent at least one element selected from the group consisting of Al, Ga, Si, Ge, Sn, and Sb, and the parameter a may satisfy the relationship 0<a?30 in terms of atomic percent.
    Type: Grant
    Filed: August 29, 2005
    Date of Patent: June 30, 2009
    Assignee: TDK Corporation
    Inventors: Naoya Hasegawa, Masamichi Saito, Yosuke Ide, Masahiko Ishizone
  • Patent number: 7502210
    Abstract: A magnetic detecting device having a large ?RA value is provided. A free magnetic layer has a three layer structure in which a CoFe layer, a NiaFeb alloy layer (here, a and b are represented by at %, and satisfy the relationship of 47?a?77 and a+b=100), and a CoFe layer are laminated. In addition, pinned magnetic layers have heusler alloy layers, which are made of a heusler alloy such as a Co2MnGe alloy. Accordingly, the product ?RA of a magnetic resistance variation ?R of the magnetic detecting device and an area A of the device can have a value of 5 m??m2 more.
    Type: Grant
    Filed: February 28, 2006
    Date of Patent: March 10, 2009
    Assignee: Alps Electric Co., Ltd.
    Inventors: Yosuke Ide, Masamichi Saito, Masahiko Ishizone, Naoya Hasegawa
  • Patent number: 7499249
    Abstract: A magnetic detecting element capable of maintaining a large ?RA and reducing magnetostriction by changing a material of a free magnetic layer, and a method of manufacturing the same is provided. A CoMnXZ alloy layer or CoMnXRh alloy layer is formed in a free magnetic layer where an element X is at least one or two elements of Ge, Ga, In, Si, Pb, and Zn, and an element X in the latter case is at least one or two elements of Ge, Ga, In, Si, Pb, Zn, Sn, Al, and Sb. By forming the CoMnXZ alloy layer or the CoMnXRh alloy layer in the free magnetic layer, the magnetostriction of the free magnetic layer can be reduced while maintaining the large ?RA, compared with a case where only the CoMnX alloy is formed.
    Type: Grant
    Filed: April 24, 2006
    Date of Patent: March 3, 2009
    Assignee: TDK Corporation
    Inventors: Yosuke Ide, Masamichi Saito, Masahiko Ishizone, Naoya Hasegawa