Patents by Inventor Susumu Okamura
Susumu Okamura 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).
-
Publication number: 20160086623Abstract: Embodiments disclosed herein generally relate to a MAMR head. The MAMR head includes an STO. The STO has a first magnetic layer, a second magnetic layer and an interlayer disposed between the first and second magnetic layers. One of the first and second magnetic layers is made of a negative polarization material while the other magnetic layer is made of a positive polarization material. As a result, the magnetizations in the first and second magnetic layers are in the same direction when in oscillation, which suppresses the partial cancellation of the magnetizations in the first and second magnetic layers and strengthens the AC magnetic field.Type: ApplicationFiled: September 23, 2014Publication date: March 24, 2016Inventors: Keiichi NAGASAKA, Yo SATO, Masato SHIIMOTO, Masashige SATO, Masukazu IGARASHI, Susumu OKAMURA
-
Patent number: 9230569Abstract: In one embodiment, a magnetic head includes a main magnetic pole positioned configured to generate a writing magnetic field when current is applied to a write coil, and a spin torque oscillator (STO) located adjacent the main magnetic pole, the STO being configured to generate a high frequency magnetic field when current is applied thereto, wherein the high frequency magnetic field is generated simultaneously to the writing magnetic field to assist in reversing magnetization of a magnetic recording medium. The STO includes: a spin polarization layer (SPL), a field generation layer (FGL) positioned adjacent the SPL, and one or more interlayers positioned between the SPL and the FGL, and a magnetization easy axis of the SPL is positioned in an in-plane direction such that the SPL has no perpendicular magnetic anisotropy.Type: GrantFiled: November 26, 2014Date of Patent: January 5, 2016Assignee: HGST Netherlands B.V.Inventors: Masato Shimoto, Masukazu Igarashi, Keiichi Nagasaka, Yo Sato, Susumu Okamura, Masashige Sato
-
Patent number: 9177575Abstract: A tunneling magnetoresistive (TMR) read head has a read gap with a reduced thickness. A multilayer seed layer includes a first ferromagnetic seed layer on the lower shield, a ferromagnetic NiFe alloy on the first seed layer, and a third seed layer of Ru or Pt on the NiFe seed layer. The first and NiFe seed layers are magnetically part of the lower shield, thereby effectively reducing the read gap thickness. A free layer/capping layer structure includes a multilayer ferromagnetic free layer and a Hf capping layer on the free layer. The free layer includes a B-containing upper layer in contact with the Hf capping layer prior to annealing. When the sensor is annealed Hf diffuses into the B-containing upper layer, forming an interface layer. The Hf-containing interface layer possesses negative magnetostriction, so the free layer is not required to contain NiFe.Type: GrantFiled: December 5, 2014Date of Patent: November 3, 2015Assignee: HGST Netherlands B.V.Inventors: Zheng Gao, Sangmun Oh, Susumu Okamura
-
Patent number: 9099107Abstract: In one embodiment, a spin torque oscillator (STO) includes a reference layer having a magnetization that is capable of free in-plane rotation, a field generation layer (FGL) including at least one magnetic film having an easy magnetization plane effectively in a film plane, wherein a magnetization of the FGL is capable of in-plane rotation, and a stabilizing layer (STL) positioned on a side of the FGL opposite the reference layer, the STL including a magnetic film having an easy magnetization plane effectively in a film plane, wherein a magnetization of the STL is capable of in-plane rotation, wherein a product of a saturation magnetization of the STL multiplied by a thickness of the STL is less than half a product of a magnetization of the FGL multiplied by a thickness of the FGL.Type: GrantFiled: January 23, 2015Date of Patent: August 4, 2015Assignee: HGST Netherlands B.V.Inventors: Masukazu Igarashi, Keiichi Nagasaka, Susumu Okamura, Yo Sato, Masashige Sato, Masato Shimoto
-
Publication number: 20150062759Abstract: Embodiments of the present invention generally relate to a magnetic head having a sensor structure comprising a pinned layer, a spacer layer, a free layer and a capping structure. The free layer has a topmost layer comprising CoB and the capping structure comprises an X layer, where X is an element such as Hf, Zr, Ti, V, Nb, or Ta.Type: ApplicationFiled: August 28, 2013Publication date: March 5, 2015Inventors: Chando PARK, Zheng GAO, Sangmun OH, Susumu OKAMURA, James Mac FREITAG
-
Patent number: 8958180Abstract: Embodiments of the present invention generally relate to a magnetic head having a sensor structure comprising a pinned layer, a spacer layer, a free layer and a capping structure. The free layer has a topmost layer comprising CoB and the capping structure comprises an X layer, where X is an element such as Hf, Zr, Ti, V, Nb, or Ta.Type: GrantFiled: August 28, 2013Date of Patent: February 17, 2015Assignee: HGST Netherlands, B.V.Inventors: Chando Park, Zheng Gao, Sangmun Oh, Susumu Okamura, James Mac Freitag
-
Publication number: 20140133052Abstract: A magnetic read head having a reduced read gap and a stable magnetic pinned layer structure. The sensor includes a seed layer that has a surface formed with an anisotropic texture. A magnetic pinned layer formed over the seed layer has a body centered cubic structure which causes the pinned layer structure to have a magnetic anisotropy with an easy axis oriented perpendicular to the air bearing surface when deposited over the textured seed layer. A magnetic free layer structure formed over the pinned layer structure and over a non-magnetic barrier layer has a face centered cubic structure which causes the magnetic free layer to have a magnetic anisotropy with an easy axis oriented parallel with the air bearing surface.Type: ApplicationFiled: November 14, 2012Publication date: May 15, 2014Applicant: HGST NETHERLANDS B.V.Inventors: Kenichi Meguro, Keizo Kato, Susumu Okamura, Nobuo Yoshida
-
Patent number: 8570690Abstract: A magnetic sensor having a novel hard bias structure that provides reduced gap spacing for increased data density. The magnetic sensor includes a sensor stack with first and second sides formed on a magnetic shield. A thin insulation layer is formed over the sides of the sensor stack and over the bottom shield. An under-layer comprising Cu—O is formed over the insulation layer and a hard magnetic bias layer is formed over the under-layer. The use of Cu—O as the under-layer allows the under-layer to be made thinner while still maintaining excellent magnetic properties in the hard bias layers formed there-over. This reduced thickness of the under-layer allows the gap spacing (spacing between the top and bottom magnetic shields) to be reduced, which in turn provides increased data density.Type: GrantFiled: June 20, 2011Date of Patent: October 29, 2013Assignee: HGST Netherlands B.V.Inventors: Susumu Okamura, Hiroyuki Hoshiya, Takahiro Ibusuki
-
Patent number: 8451565Abstract: In one embodiment, a magnetic head includes a lower shield layer, a sensor stack positioned above the lower shield layer, the sensor stack including a free layer, a layered hard bias magnet positioned above the lower shield layer and on both sides of the sensor stack in a track width direction, and an upper shield layer positioned above the hard bias magnet and the sensor stack. The hard bias magnet includes a perpendicular anisotropy film positioned above the lower shield layer and aligned with both sides of the sensor stack in the track width direction, wherein the perpendicular anisotropy film directs magnetic fields in a direction perpendicular to planes of formation thereof, and an in-plane anisotropy film positioned above the perpendicular anisotropy film, wherein the in-plane anisotropy film directs magnetic fields in a direction of planes of formation thereof.Type: GrantFiled: November 21, 2011Date of Patent: May 28, 2013Assignee: HGST Netherlands B.V.Inventors: Susumu Okamura, Takahiro Ibusuki
-
Publication number: 20130128381Abstract: In one embodiment, a magnetic head includes a lower shield layer, a sensor stack positioned above the lower shield layer, the sensor stack including a free layer, a layered hard bias magnet positioned above the lower shield layer and on both sides of the sensor stack in a track width direction, and an upper shield layer positioned above the hard bias magnet and the sensor stack. The hard bias magnet includes a perpendicular anisotropy film positioned above the lower shield layer and aligned with both sides of the sensor stack in the track width direction, wherein the perpendicular anisotropy film directs magnetic fields in a direction perpendicular to planes of formation thereof, and an in-plane anisotropy film positioned above the perpendicular anisotropy film, wherein the in-plane anisotropy film directs magnetic fields in a direction of planes of formation thereof.Type: ApplicationFiled: November 21, 2011Publication date: May 23, 2013Applicant: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Susumu Okamura, Takahiro Ibusuki
-
Publication number: 20120320473Abstract: A magnetic sensor having a novel hard bias structure that provides reduced gap spacing for increased data density. The magnetic sensor includes a sensor stack with first and second sides formed on a magnetic shield. A thin insulation layer is formed over the sides of the sensor stack and over the bottom shield. An under-layer comprising Cu—O is formed over the insulation layer and a hard magnetic bias layer is formed over the under-layer. The use of Cu—O as the under-layer allows the under-layer to be made thinner while still maintaining excellent magnetic properties in the hard bias layers formed thereover. This reduced thickness of the under-layer allows the gap spacing (spacing between the top and bottom magnetic shields) to be reduced, which in turn provides increased data density.Type: ApplicationFiled: June 20, 2011Publication date: December 20, 2012Applicant: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Susumu Okamura, Hiroyuki Hoshiya, Takahiro Ibusuki
-
Patent number: 8189304Abstract: A magnetoresistive magnetic head according to one embodiment uses a current-perpendicular-to-plane magnetoresistive element having a laminate of a free layer, an intermediate layer, and a pinned layer, the pinned layer being substantially fixed to a magnetic field to be detected, wherein either the pinned layer or the free layer includes a Heusler alloy layer represented by a composition of X—Y—Z, wherein X is between about 45 at. % and about 55 at. % and is Co or Fe, Y accounts for between about 20 at. % and about 30 at. % and is one or more elements selected from V, Cr, Mn, and Fe, and Z is between about 20 at. % and about 35 at.Type: GrantFiled: December 11, 2009Date of Patent: May 29, 2012Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Susumu Okamura, Yo Sato, Katsumi Hoshino, Hiroyuki Hoshiya, Kenichi Meguro, Keizo Kato
-
Publication number: 20120071569Abstract: To provide a method for producing a gel of a carboxymethyl cellulose alkali metal salt, in which a gel having high elasticity and strength and also having excellent water retention and durability can be obtained inexpensively and simply. The method for producing a gel of a carboxymethyl cellulose alkali metal salt of the present invention includes previously mixing a mixture containing a carboxymethyl cellulose alkali metal salt and a water retention agent and subsequently mixing the resulting mixture with an acid aqueous solution to obtain a gel.Type: ApplicationFiled: October 30, 2009Publication date: March 22, 2012Inventors: Machiko Takigami, Akihiro Hiroki, Naotsugu Nagasawa, Kozo Miyaj, Susumu Okamura
-
Publication number: 20100188771Abstract: A magnetoresistive magnetic head according to one embodiment uses a current-perpendicular-to-plane magnetoresistive element having a laminate of a free layer, an intermediate layer, and a pinned layer, the pinned layer being substantially fixed to a magnetic field to be detected, wherein either the pinned layer or the free layer includes a Heusler alloy layer represented by a composition of X-Y-Z, wherein X is between about 45 at. % and about 55 at. % and is Co or Fe, Y accounts for between about 20 at. % and about 30 at. % and is one or more elements selected from V, Cr, Mn, and Fe, and Z is between about 20 at. % and about 35 at.Type: ApplicationFiled: December 11, 2009Publication date: July 29, 2010Inventors: Susumu Okamura, Yo Sato, Katsumi Hoshino, Hiroyuki Hoshiya, Kenichi Meguro, Keizo Kato
-
Patent number: 5766375Abstract: A non-oriented magnetic steel sheet having excellent bending workability and magnetic characteristics is obtained by continuous annealing. The non-oriented magnetic steel sheet is obtained by the method comprising cold rolling a hot-rolled steel sheet, continuously annealing the steel sheet, and then performing skin pass rolling; the steel has a composition comprising about 0.005 mass % or less of C, about 0.05 to 0.30 mass % of Si, about 0.10 to 0.50 mass % of Mn, about 0.15 to 0.50 mass % of Al, and about 0.0050 mass % or less of N.Type: GrantFiled: March 21, 1997Date of Patent: June 16, 1998Assignee: Kawasaki Steel CorporationInventors: Susumu Okamura, Etsuji Hino, Yoshinori Fujita, Masaki Shimizu, Tetsuya Aoki, Shoichi Takenouchi
-
Patent number: 5629553Abstract: A variable inductance element comprising an inductor conductor 10 having a predetermined shape formed on an insulation layer 40 on the surface of a semiconductor substrate 42, switches 16 and 24 for shorting portions of the inductor conductor 10, and input/output terminals 12 and 14 provided at the respective ends of the inductor conductor 10. When switches 16 and/or 24 is in the on state, the function as an inductor having a smaller inductance than the overall inductor conductor 10 is obtained. The inductance of this variable inductance element can be changed by external control, while manufacturing is easy and formation in a unitized manner with an integrated circuit or other semiconductor device is enabled.Type: GrantFiled: November 14, 1994Date of Patent: May 13, 1997Assignees: Takeshi Ikeda, Susumu OkamuraInventors: Takeshi Ikeda, Susumu Okamura, Akira Okamoto
-
Patent number: 5557138Abstract: An LC element with a pn junction layer formed near the surface of a p-Si substrate by forming an n.sup.+ region having a predetermined shape and in a portion thereof additionally forming a p.sup.+ region having the same shape, and with first and second electrodes formed over entire length on the surface of this pn junction layer; wherein the two electrodes respectively function as inductors and by using the pn junction layer with reverse bias, a distributed constant type capacitor is formed between these inductors, thereby providing excellent attenuation characteristics over a wide band, a semiconductor device including the LC element, and a method of manufacturing the LC element.Type: GrantFiled: October 26, 1994Date of Patent: September 17, 1996Inventors: Takeshi Ikeda, Susumu Okamura
-
Patent number: 5497028Abstract: An LC element and an semiconductor device comprising a second electrode having a predetermined shape formed in direct contact with the surface of a semiconductor substrate, and a first electrode having a predetermined shape formed interspaced by an insulation layer on the semiconductor substrate surface; and a method of manufacturing the LC element. A channel formed along the first electrode on application of a predetermined gate voltage to a control electrode connected to the first electrode and the second electrode respectively function as inductors, while a distributed constant type capacitor is also formed between these; and by using the channel as a signal transmission line, the LC element and a semiconductor device give excellent attenuation characteristics. The LC element and semiconductor device are easily manufactured, while parts assembly work in subsequent processing can be abbreviated, formation as a portion of an IC or LSI device is possible, and characteristics can also be controlled.Type: GrantFiled: November 2, 1994Date of Patent: March 5, 1996Inventors: Takeshi Ikeda, Susumu Okamura
-
Patent number: 5492856Abstract: An LC element with a pn junction layer formed near the surface of a p-Si substrate by forming an n.sup.+ region having a predetermined shape and in a portion thereof additionally forming a p.sup.+ region having the same shape, and with first and second electrodes formed over entire length on the surface of this pn junction layer; wherein the two electrodes respectively function as inductors and by using the pn junction layer with reverse bias, a distributed constant type capacitor is formed between these inductors, thereby providing excellent attenuation characteristics over a wide band, a semiconductor device including the LC element, and a method of manufacturing the LC element.Type: GrantFiled: June 2, 1995Date of Patent: February 20, 1996Inventors: Takeshi Ikeda, Susumu Okamura