Inventor · disambiguated record
Keiichi Nagasaka
Also filed as: NAGASAKA KEIICHI
38 granted patents·11 pending applications·552 citations·filing 1998–2022
98Inventor score
Top patents by PatentIndex Score
49 records- 0198US10037772B2Low magnetic flux density interface layer for spin torque oscillatorWESTERN DIGITAL TECH INC·Filed 2017·Granted Jul 31, 2018·33 cites·20 claims
- 0297US6927952B2CPP GMR free layer having ferromagnetic layers with parallel magnetization separated by non-magnetic layerFUJITSU LTD·Filed 2002·Granted Aug 9, 2005·90 cites·21 claims
- 0396US9805746B1Low magnetic flux density interface layer for spin torque oscillatorHGST Netherlands BV·Filed 2016·Granted Oct 31, 2017·19 cites·22 claims
- 0495US8879205B2High spin-torque efficiency spin-torque oscillator (STO) with dual spin polarization layerHGST Netherlands BV·Filed 2012·Granted Nov 4, 2014·32 cites·20 claims
- 0594US9230569B1Low Bs spin-polarizer for spin torque oscillatorHGST Netherlands BV·Filed 2014·Granted Jan 5, 2016·30 cites·20 claims
- 0694US8988826B2MAMR head with a multi-layered side gap for stable oscillation of the STOHGST Netherlands BV·Filed 2012·Granted Mar 24, 2015·25 cites·13 claims
- 0794US8537497B2Magnetic recording head and magnetic recording/reproducing apparatusNAGASAKA KEIICHI·Filed 2012·Granted Sep 17, 2013·27 cites·20 claims
- 0893US9728210B2Texture-control layer for spin torque oscillatorHGST Netherlands BV·Filed 2015·Granted Aug 8, 2017·13 cites·20 claims
- 0993US9099107B1Stabilizing layer for a spin torque oscillator (STO)HGST Netherlands BV·Filed 2015·Granted Aug 4, 2015·22 cites·20 claims
- 1092US9378759B2Spin torque oscillator with low magnetic moment and high perpendicular magnetic anisotropy materialHGST Netherlands BV·Filed 2014·Granted Jun 28, 2016·17 cites·23 claims
- 1192US8345380B2Spin torque oscillator and magnetic recording head and magnetic recording device mounted with the spin torque oscillatorHITACHI LTD·Filed 2011·Granted Jan 1, 2013·19 cites·18 claims
- 1291US8970996B2Spin-torque oscillator for microwave assisted magnetic recordingHGST Netherlands BV·Filed 2012·Granted Mar 3, 2015·25 cites·20 claims
- 1391US8687319B2Magnetic recording apparatus with magnetic recording head capable of recording information on a magnetic recording mediumIGARASHI MASUKAZU·Filed 2012·Granted Apr 1, 2014·16 cites·12 claims
- 1491US7342751B2Magnetoresistive effect having multiple base layers between an electrode and an antiferromagnetic layer, magnetic head, and magnetic recording deviceFUJITSU LTD·Filed 2005·Granted Mar 11, 2008·13 cites·20 claims
- 1589US9305574B1Negative-polarization spin-torque-oscillatorHGST Netherlands BV·Filed 2014·Granted Apr 5, 2016·10 cites·12 claims
- 1689US8547656B2Spin-torque oscillator (STO) for microwave-assisted magnetic recording (MAMR) and methods of use thereofIGARASHI MASUKAZU·Filed 2012·Granted Oct 1, 2013·11 cites·20 claims
- 1788US9406315B2AF-mode STO with negative Hk spin polarization layerHGST Netherlands BV·Filed 2014·Granted Aug 2, 2016·11 cites·15 claims
- 1887US7428127B2CPP magnetoresistive effect element and magnetic storage device having a CPP magnetoresistive effect elementFUJITSU LTD·Filed 2005·Granted Sep 23, 2008·7 cites·11 claims
- 1985US9230597B2Magnetic head having a spin torque oscillator (STO) with a hybrid heusler field generation layer (FGL)HGST Netherlands BV·Filed 2013·Granted Jan 5, 2016·8 cites·19 claims
- 2081US6781799B2Current perpendicular-to-the-plane structure spin valve magnetoresistive headFUJITSU LTD·Filed 2001·Granted Aug 24, 2004·24 cites·18 claims
- 2178US8773822B2Spin-torque oscillator for microwave assisted magnetic recordingMATSUBARA MASATO·Filed 2011·Granted Jul 8, 2014·4 cites·17 claims
- 2278US6995960B2Spin valve magnetoresistive sensor having CPP structureFUJITSU LTD·Filed 2001·Granted Feb 7, 2006·19 cites·8 claims
- 2376US9437222B1Spin torque oscillator with high spin torque efficiency and reliabilityHGST Netherlands BV·Filed 2015·Granted Sep 6, 2016·4 cites·13 claims
- 2475US7180713B2Magnetoresistive elementFUJITSU LTD·Filed 2002·Granted Feb 20, 2007·15 cites·10 claims
- 2572US8982502B2Hard disk drive with write assist based on detected conditionsMORINAGA AKIRA·Filed 2011·Granted Mar 17, 2015·4 cites·19 claims
- 2671US9336797B2Extended spin torque oscillatorHGST Netherlands BV·Filed 2014·Granted May 10, 2016·2 cites·20 claims
- 2770US9858952B1Microwave assisted magnetic recording head having spin torque oscillator frequency detectionHGST Netherlands BV·Filed 2016·Granted Jan 2, 2018·2 cites·20 claims
- 2868US7538987B2CPP spin-valve elementUNIV ALABAMA·Filed 2003·Granted May 26, 2009·7 cites·13 claims
- 2967US7116533B2Magnetoresistive sensorFUJITSU LTD·Filed 2006·Granted Oct 3, 2006·4 cites·6 claims
- 3067US6661624B1Spin-valve magnetoresistive device having a layer for canceling a leakage magnetic fieldFUJITSU LTD·Filed 2000·Granted Dec 9, 2003·6 cites·8 claims
- 3164US7116528B2Magnetoresistive element having current-perpendicular-to-the-plane structure and having improved magnetic domain controlFUJITSU LTD·Filed 2003·Granted Oct 3, 2006·10 cites·12 claims
- 3257US6034845ASpin-valve magnetic head with the pinned layer having different directions for its magnetization axis and its easy axisFUJITSU LTD·Filed 1998·Granted Mar 7, 2000·9 cites·3 claims
- 3353US6801413B2Magnetic sensor, magnetic head and magnetic recording apparatusFUJITSU LTD·Filed 2002·Granted Oct 5, 2004·5 cites·16 claims
- 3453US2010053794A1Thermally assisted magnetic recording method, magnetic recording head, magnetic recording medium, and magnetic recording apparatusFUJITSU LTD·Filed 2009·Application pending·0 cites
- 3552US9990943B2Texture-control layer for spin torque oscillatorWESTERN DIGITAL TECH INC·Filed 2017·Granted Jun 5, 2018·0 cites·19 claims
- 3651US2024274436A1Film forming method and substrate processing deviceTOKYO ELECTRON LTD·Filed 2022·Application pending·0 cites
- 3750US7450351B2Magnetoresistive element having current-perpendicular-to-plane structure, magnetic head, and magnetic memory apparatus thereofFUJITSU LTD·Filed 2005·Granted Nov 11, 2008·1 cites·9 claims
- 3850US7433160B2Magnetoresistive element and method of manufacturing the sameFUJITSU LTD·Filed 2005·Granted Oct 7, 2008·0 cites·10 claims
- 3946US2007217083A1Magnetoresistive effect device and method of manufacturing ferromagnetic structureFUJITSU LTD·Filed 2006·Application pending·0 cites
- 4045US2008080097A1Magnetoresistive element, method of manufacturing the same, and magnetic storage unitFUJITSU LTD·Filed 2007·Application pending·0 cites
- 4144US2009323406A1Magnetic memory element, and method of manufacturing memory elementFUJITSU LTD·Filed 2009·Application pending·0 cites
- 4244US2015103431A1Sto with anti-ferromagnetic coupling interlayerHGST Netherlands BV·Filed 2013·Application pending·0 cites
- 4343US6364961B1Spin-valve magnetic head with the pinned layer having different directions for its magnetization axis and its easy axisFUJITSU LTD·Filed 1999·Granted Apr 2, 2002·4 cites·6 claims
- 4443US6355115B1Spin-valve magnetic head with the pinned layer having different directions for its magnetization axis and its easy axisFUJITSU LTD·Filed 1999·Granted Mar 12, 2002·4 cites·11 claims
- 4542US2007048485A1Magnetoresistive effect element, magnetic head, magnetic storage device and magnetic memory deviceFUJITSU LTD·Filed 2006·Application pending·0 cites
- 4641US2012113542A1Oscillator in which polarity is changed at high speed, magnetic head for mamr and fast data transfer rate hddIGARASHI MASUKAZU·Filed 2011·Application pending·0 cites
- 4740US2003128481A1Current-perpendicular-to-the-plane structure magnetoresistive headFUJITSU LTD·Filed 2002·Application pending·0 cites
- 4838US2010054033A1Magnetic thin line and memory deviceFUJITSU LTD·Filed 2009·Application pending·0 cites
- 4938US2010061135A1Magnetic wire unit and storage deviceFUJITSU LTD·Filed 2009·Application pending·0 cites
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →