Patents by Inventor Eric Edward Fullerton

Eric Edward Fullerton 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: 8263239
    Abstract: A laminated magnetic recording structure for use in perpendicular or longitudinal recording is described. A small amount of ferromagnetic coupling is added between the two magnetic layers that are sufficiently decoupled to switch independently. In one embodiment the coupling is achieved by doping the spacer layer with a ferromagnetic material. Ruthenium (Ru), which is a preferred nonmagnetic material for spacer layers with cobalt (Co) being the preferred magnetic material. The weak ferromagnetic coupling can also be achieved through the use of platinum, palladium and alloys thereof for the spacer layer without the addition of a ferromagnetic element, but alternatively they can also be doped with ferromagnetic elements. For embodiments for perpendicular recording the spacer layer further can additionally comprise oxides of one or more elements selected from the group consisting of Si, Ta, Ti, Nb, Cr, V and B.
    Type: Grant
    Filed: June 26, 2006
    Date of Patent: September 11, 2012
    Assignee: HGST Netherlands B.V.
    Inventors: Andreas Klaus Berger, Hoa Van Do, Eric Edward Fullerton, David Thomas Margulies, Natacha Frederique Supper
  • Patent number: 7989096
    Abstract: A recording medium providing improved writeability in perpendicular recording applications includes a magnetic recording layer having an axis of magnetic anisotropy substantially perpendicular to the surface thereof, an exchange-spring layer ferromagnetically exchange coupled to the magnetic recording layer and having a coercivity less than the magnetic recording layer coercivity, and a coupling layer between the magnetic recording layer and the exchange-spring layer. The coupling layer regulates the ferromagnetic exchange coupling between the magnetic recording layer and the exchange-spring layer.
    Type: Grant
    Filed: January 21, 2010
    Date of Patent: August 2, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Andreas Berger, Eric Edward Fullerton, Hoa Van Do, Natacha Supper
  • Patent number: 7976964
    Abstract: The invention includes a disk drive with a magnetic recording disk with an upper and lower sublayer in at least one magnetic layer of a laminated magnetic layer structure that includes a spacer layer that substantially decouples the magnetic layers. The lower sublayer has a lower boron content than the upper sublayer and a preferred embodiment is CoPtCrBTa. The upper sublayer is deposited onto the lower sublayer and is preferably CoPtCrB with a higher boron content than the lower sublayer. The composition of the lower sublayer gives it a very low moment with low intrinsic coercivity which would not be useful as a recording layer on its own. The upper sublayer is a higher moment alloy with high intrinsic coercivity. An embodiment of the invention includes a laminated magnetic layer structure which is antiferromagnetically coupled to a lower ferromagnetic layer.
    Type: Grant
    Filed: March 18, 2005
    Date of Patent: July 12, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hoa Van Do, Eric Edward Fullerton, David Thomas Margulies, Natacha Frederique Supper
  • Patent number: 7732071
    Abstract: A patterned perpendicular magnetic recording medium of the type that has spaced-apart pillars with magnetic material on their ends and with nonmagnetic trenches between the pillars is made with a method that allows use of a pre-etched substrate. The substrate has a generally planar surface at the trenches and comprises material that when heated will diffuse into the magnetic recording layer material and chemically react with one or more of the elements typically used in the recording layer. The pillars are formed of material that will not diffuse into the recording layer. After the recording layer is formed over the entire substrate so as to cover both the pillar ends and the trenches, the substrate is annealed. This results in the destruction or at least substantial reduction of any ferromagnetism in the recording layer material in the trenches so that the trenches are nonmagnetic.
    Type: Grant
    Filed: November 10, 2006
    Date of Patent: June 8, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Eric Edward Fullerton, Olav Hellwig, Jeffrey S. Lille, James Terrence Olson, Petrus Antonius VanDerHeijden, Henry Hung Yang
  • Publication number: 20100128391
    Abstract: A recording medium providing improved writeability in perpendicular recording applications includes a magnetic recording layer having an axis of magnetic anisotropy substantially perpendicular to the surface thereof, an exchange-spring layer ferromagnetically exchange coupled to the magnetic recording layer and having a coercivity less than the magnetic recording layer coercivity, and a coupling layer between the magnetic recording layer and the exchange-spring layer. The coupling layer regulates the ferromagnetic exchange coupling between the magnetic recording layer and the exchange-spring layer.
    Type: Application
    Filed: January 21, 2010
    Publication date: May 27, 2010
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Andreas Berger, Eric Edward Fullerton, Hoa Van Do, Natacha Supper
  • Patent number: 7687157
    Abstract: A recording medium providing improved writeability in perpendicular recording applications includes a magnetic recording layer having an axis of magnetic anisotropy substantially perpendicular to the surface thereof, an exchange-spring layer ferromagnetically exchange coupled to the magnetic recording layer and having a coercivity less than the magnetic recording layer coercivity, and a coupling layer between the magnetic recording layer and the exchange-spring layer. The coupling layer regulates the ferromagnetic exchange coupling between the magnetic recording layer and the exchange-spring layer.
    Type: Grant
    Filed: September 21, 2005
    Date of Patent: March 30, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Andreas Berger, Eric Edward Fullerton, Hoa Van Do, Natacha Supper
  • Patent number: 7672090
    Abstract: A magnetoresistive sensor having a hard magnetic pinning layer with an engineered magnetic anisotropy in a direction substantially perpendicular to the medium facing surface. The hard magnetic pinning layer may be constructed of CoPt, CoPtCr, or some other magnetic material and is deposited over an underlayer that has been ion beam etched. The ion beam etch has been performed at an angle with respect to normal in order to induce anisotropic roughness for example in form of oriented ripples or facets oriented along a direction parallel to the medium facing surface. The anisotropic roughness induces a strong uniaxial magnetic anisotropy substantially perpendicular to the medium facing surface in the hard magnetic pinning layer deposited there over.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: March 2, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Eric Edward Fullerton, Stefan Maat
  • Patent number: 7556870
    Abstract: An embodiment of the invention is a layered magnetic thin film structure that uses antiferromagnetically coupled (AFC) magnetic layers where the top layer structure consists of an upper magnetic layer that is weakly ferromagnetically coupled via a nonmagnetic or weakly magnetic exchange coupling layer (interlayer) to a ferromagnetic exchange enhancing layer that is in turn, AF coupled to the lower ferromagnetic layer of the AFC structure. Preferred materials for the weak coupling layer include alloys of cobalt such as CoRu, CoBRu and CoCr in which the Co content is below the point at which the material would be ferromagnetic. A second embodiment of the invention is a laminated, AF-coupled media structure. In this structure the lower AFC layer that makes up the lower laminate layer includes: the middle magnetic layer, the weak ferromagnetic coupling layer, and the exchange enhancing layer.
    Type: Grant
    Filed: August 15, 2005
    Date of Patent: July 7, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hoa Van Do, Eric Edward Fullerton, David Thomas Margulies, Natacha Frederique Supper
  • Publication number: 20090155627
    Abstract: A media architecture is optimized for discrete track recording. A capped or exchange-spring media uses a thin media structure and incorporates higher moment density magnetic layers. A thin exchange coupling layer is used in conjunction with a cap layer to control the reversal mechanism and exchange. Thus, the exchange coupling layer mediates the interaction between the two outer magnetic layers. The thickness of the exchange coupling layer is tuned by monitoring the media signal-to-noise ratio, track width and bit error rate. The recording performance is enhanced by tuning the intergranular exchange in the system through the use of the high-moment cap as writeability, resolution and noise are improved.
    Type: Application
    Filed: December 14, 2007
    Publication date: June 18, 2009
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Andreas Klaus Berger, Eric Edward Fullerton, Byron Hassberg Lengsfield, III, James Terrence Olson
  • Patent number: 7529065
    Abstract: The invention uses an upper and lower magnetic layer of a laminated magnetic layer structure that includes an AF spacer layer that results in weak antiferromagnetic coupling of the magnetic layers that is insufficient to cause either of the layers to switch so that the magnetic orientations of the two ferromagnetic layers remain parallel. An advantage of the invention is that the AF-coupling tends to anti-correlate the noise in the two layers. The weak AF coupling according to the invention is believed to act at the transition boundaries in the media to cause some of the noise domains to be oriented antiparallel and the noise to be less correlated than would be the case without the AF coupling and thereby to achieve improved SNR.
    Type: Grant
    Filed: May 19, 2005
    Date of Patent: May 5, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Eric Edward Fullerton, Olav Hellwig, Byron Hassberg Lengsfield, III, David T. Margulies
  • Patent number: 7479332
    Abstract: A method and apparatus for improving the signal-to-noise ratio in a longitudinal recording media is disclosed. The apparatus includes a first recording layer of the longitudinal recording media residing at the top of a recording media structure. The first recording layer includes an upper sublayer comprised of a CoPtCrB-based alloy material. The first recording layer also includes a lower sublayer comprised of a CoPtCrB-based alloy material and a middle sublayer comprised of a CoCrB-alloy. The middle sublayer is coupled to the upper sublayer and to the lower sublayer and is substantially thinner than the upper sublayer and the lower sublayer.
    Type: Grant
    Filed: March 7, 2005
    Date of Patent: January 20, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Eric Edward Fullerton, David Thomas Margulies, Natacha Supper, Hoa Van Do
  • Patent number: 7460343
    Abstract: A magnetoresistive sensor having an in stack bias layer with an engineered magnetic anisotropy in a direction parallel with the medium facing surface. The in-stack bias layer may be constructed of CoPt, CoPtCr or some other magnetic material and is deposited over an underlayer that has been ion beam etched. The ion beam etch has been performed at an angle with respect to normal in order to form anisotropic roughness in form of oriented ripples or facets. The anisotropic roughness induces a uniaxial magnetic anisotropy substantially parallel to the medium facing surface in the hard magnetic in-stack bias layer deposited thereover.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: December 2, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Eric Edward Fullerton, Stefan Maat
  • Patent number: 7457085
    Abstract: A magnetoresistive sensor having a hard bias layer with an engineered magnetic anisotropy in a direction substantially parallel with the medium facing surface. The hard bias layer may be constructed of CoPt, CoPtCr or some other magnetic material and is deposited over an underlayer that has been ion beam etched. The ion beam etch has been performed at an angle with respect to normal in order to induce anisotropic roughness on its surface for example in form of oriented ripples or facets. The anisotropic roughness induces a uniaxial magnetic anisotropy substantially parallel to the medium facing surface in the hard magnetic bias layers deposited there over.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: November 25, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Eric Edward Fullerton, Stefan Maat
  • Patent number: 7425377
    Abstract: A laminate structure is disclosed comprising multiple ferromagnetic layers achieving incoherent reversal while maintaining good SNR. A high magnetic moment density, low anisotropy field material may form a thin overlayer deposited over a high-anisotropy media layer. The media layer may have a lower magnetic moment density than the overlayer and have decoupled magnetic grains. A coupling layer may be interposed between the overlayer and the media layer to modulate the exchange there between, thereby reducing the pass-through of noise while still promoting incoherent reversal to achieve reduced write energy requirements.
    Type: Grant
    Filed: February 4, 2005
    Date of Patent: September 16, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Eric Edward Fullerton, Hoa Van Do, David Thomas Margulies, Natacha Supper
  • Patent number: 7382590
    Abstract: A magnetic head having a free layer and an antiparallel (AP) pinned layer structure spaced apart from the free layer. The AP pinned layer structure includes at least two pinned layers having magnetic moments that are self-pinned antiparallel to each other, the pinned layers being separated by an AP coupling layer constructed of a Ru alloy. The use of a Ru alloy coupling layer significantly increases the pinning field of the AP pinned layer structure over a pure Ru spacer.
    Type: Grant
    Filed: January 31, 2005
    Date of Patent: June 3, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Mary Frances Doerner, Eric Edward Fullerton, Wen-yaung Lee, Jinshan Li, Brian R. York
  • Publication number: 20080112079
    Abstract: A patterned perpendicular magnetic recording medium of the type that has spaced-apart pillars with magnetic material on their ends and with nonmagnetic trenches between the pillars is made with a method that allows use of a pre-etched substrate. The substrate has a generally planar surface at the trenches and comprises material that when heated will diffuse into the magnetic recording layer material and chemically react with one or more of the elements typically used in the recording layer. The pillars are formed of material that will not diffuse into the recording layer. After the recording layer is formed over the entire substrate so as to cover both the pillar ends and the trenches, the substrate is annealed. This results in the destruction or at least substantial reduction of any ferromagnetism in the recording layer material in the trenches so that the trenches are nonmagnetic.
    Type: Application
    Filed: November 10, 2006
    Publication date: May 15, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Eric Edward Fullerton, Olav Hellwig, Jeffrey S. Lille, James Terrence Olson, Petrus Antonius VanDerHeijden, Henry Hung Yang
  • Patent number: 7372116
    Abstract: A magnetic memory cell for use in a magnetic random access memory array that uses the antiferromagnetic to ferromagnetic transition properties of FeRh to assist in the control of switching of the memory cell.
    Type: Grant
    Filed: June 16, 2004
    Date of Patent: May 13, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Eric Edward Fullerton, Stefan Maat, Jan-Ulrich Thiele
  • Publication number: 20080100964
    Abstract: A magnetic recording disk drive has a bilayer recording medium of a high-anisotropy recording layer and an exchange-coupled antiferromagnetic-to-ferromagnetic (AF-F) transition layer. The transition layer has an AF-F transition temperature (TAF-F) that decreases relatively rapidly with increasing applied magnetic field. Thus the transition layer has a transition field HAF-F(T), which is the applied magnetic field required to transition the material from antiferromagnetic to ferromagnetic at temperature T without the need to heat the layer. At ambient temperature and in the absence of HW, the transition layer is antiferromagnetic and the switching field H0 of the bilayer is just the H0 of the high-anisotropy recording layer, which is typically much higher than HW.
    Type: Application
    Filed: October 26, 2006
    Publication date: May 1, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Eric Edward Fullerton, Stefan Maat, Ian Robson McFadyen, Jan-Ulrich Thiele
  • Patent number: 7363699
    Abstract: A magnetoresistive sensor having a hard bias layer with an engineered magnetic anisotropy in a direction substantially parallel with the medium facing surface. The hard bias layer may be constructed of CoPt, CoPtCr or some other magnetic material and is deposited over an underlayer that has been ion beam etched. The ion beam etch has been performed at an angle with respect to normal in order to induce anisotropic roughness on its surface for example in form of oriented ripples or facets. The anisotropic roughness induces a uniaxial magnetic anisotropy substantially parallel to the medium facing surface in the hard magnetic bias layers deposited there over.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: April 29, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B. V.
    Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Eric Edward Fullerton, Stefan Maat
  • Patent number: RE40726
    Abstract: A magnetic recording disk is patterned into discrete magnetic and nonmagnetic regions with the magnetic regions serving as the magnetic recording data bits. The magnetic recording layer comprises two ferromagnetic films separated by a nonferromagnetic spacer film. The spacer film material composition and thickness is selected such that the first and second ferromagnetic films are antiferromagnetically coupled across the spacer film. After this magnetic recording layer has been formed on the disk substrate, ions are irradiated onto it through a patterned mask. The ions disrupt the spacer film and thereby destroy the antiferromagnetic coupling between the two ferromagnetic films. As a result, in the regions of the magnetic recording layer that are ion-irradiated the first and second ferromagnetic films are essentially ferromagnetically coupled so that the magnetic moments from the ferromagnetic films are parallel and produce a magnetic moment that is essentially the sum of the moments from the two films.
    Type: Grant
    Filed: July 29, 2003
    Date of Patent: June 9, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Eric Edward Fullerton, Bruce David Terris, Dieter Klaus Weller