Patents by Inventor Jeffrey Robinson Childress
Jeffrey Robinson Childress 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: 20170133588Abstract: Embodiments disclosed herein generally relate to an electrode structure for a resistive random access memory (ReRAM) device cell which focuses the electric field at a center of the cell and methods for making the same. As such, a non-uniform metallic electrode may be deposited onto the ReRAM device which is subsequently exposed to an oxidation or nitrogenation process during cell fabrication. The electrode structure may be conical or pyramid shaped, and comprise at least one layer comprising a first material and a second material, wherein the concentration of the first material and the second material are varied based on location within the electrode. A metal electrode profile is formed which favors the center of the cell as the location with the greatest electric field. As such, size scaling and reliability of the non-volatile memory component are each increased.Type: ApplicationFiled: November 6, 2015Publication date: May 11, 2017Inventors: Daniel BEDAU, Jeffrey Robinson CHILDRESS, Oleksandr MOSENDZ, John C. READ, Derek STEWART
-
Publication number: 20160307587Abstract: Embodiments disclosed herein generally relate to a magnetic head having an amorphous ferromagnetic reference layer. The ferromagnetic reference layer may have amorphous structure as a result of an amorphous ferromagnetic underlayer that the ferromagnetic reference layer is deposited thereon. The amorphous ferromagnetic reference layer enhances magnetoresistance, leading to an improved magnetic head.Type: ApplicationFiled: June 30, 2016Publication date: October 20, 2016Inventors: Jeffrey Robinson CHILDRESS, Young-Suk CHOI, Tomoya NAKATANI, John C. READ
-
Patent number: 9412399Abstract: Embodiments disclosed herein generally relate to a magnetic head having an amorphous ferromagnetic reference layer. The ferromagnetic reference layer may have amorphous structure as a result of an amorphous ferromagnetic underlayer that the ferromagnetic reference layer is deposited thereon. The amorphous ferromagnetic reference layer enhances magnetoresistance, leading to an improved magnetic head.Type: GrantFiled: September 17, 2014Date of Patent: August 9, 2016Assignee: HGST Netherlands B.V.Inventors: Jeffrey Robinson Childress, Young-Suk Choi, Tomoya Nakatani, John Creighton Read
-
Publication number: 20160078888Abstract: Embodiments disclosed herein generally relate to a magnetic head having an amorphous ferromagnetic reference layer. The ferromagnetic reference layer may have amorphous structure as a result of an amorphous ferromagnetic underlayer that the ferromagnetic reference layer is deposited thereon. The amorphous ferromagnetic reference layer enhances magnetoresistance, leading to an improved magnetic head.Type: ApplicationFiled: September 17, 2014Publication date: March 17, 2016Inventors: Jeffrey Robinson CHILDRESS, Young-Suk CHOI, Tomoya NAKATANI, John Creighton READ
-
Patent number: 9177576Abstract: A disk drive includes a disk including a magnetizable layer of material, and a transducer. The transducer has a read element that includes a first shield layer, a pinned layer, a metallic spacer, an AP (anti-parallel) free layer, and a second shield layer. The pinned layer has a surface area which is greater than the area of the AP free layer. The read element also includes an anti-ferromagnetic layer for substantially fixing the magnetic orientation of a plurality of domains in the pinned layer. The ferromagnetic layer is adjacent the pinned layer. The pinned layer, and the anti-ferromagnetic layer both have surface areas which are greater than the area associated with the AP free layer. The anti-ferromagnetic layer, in one embodiment, has a pinning strength in the range of 0.5 erg/cm2 to 1.5 erg/cm2.Type: GrantFiled: October 3, 2013Date of Patent: November 3, 2015Assignee: HGST NETHERLANDS B.V.Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Young-suk Choi, Goran Mihajlovic, John Creighton Read, Neil Smith
-
Publication number: 20150098153Abstract: A disk drive includes a disk including a magnetizable layer of material, and a transducer. The transducer has a read element that includes a first shield layer, a pinned layer, a metallic spacer, an AP (anti-parallel) free layer, and a second shield layer. The pinned layer has a surface area which is greater than the area of the AP free layer. The read element also includes an anti-ferromagnetic layer for substantially fixing the magnetic orientation of a plurality of domains in the pinned layer. The ferromagnetic layer is adjacent the pinned layer. The pinned layer, and the anti-ferromagnetic layer both have surface areas which are greater than the area associated with the AP free layer. The anti-ferromagnetic layer, in one embodiment, has a pinning strength in the range of 0.5 erg/cm2 to 1.5 erg/cm2.Type: ApplicationFiled: October 3, 2013Publication date: April 9, 2015Applicant: HGST Netherlands B.V.Inventors: Matthew Joseph CAREY, Jeffrey Robinson CHILDRESS, Young-suk CHOI, Goran MIHAJLOVIC, John Creighton READ, Neil SMITH
-
Patent number: 8228644Abstract: A CPP spin-valve magnetic head, according to one embodiment includes a ferromagnetic free layer having a bias-point magnetization nominally oriented in a first direction; a ferromagnetic reference layer film having a bias-point magnetization nominally oriented in a second direction that is not orthogonal to the said first direction; and a tunnel barrier layer between the free and reference layers.Type: GrantFiled: January 26, 2012Date of Patent: July 24, 2012Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Jeffrey Robinson Childress, Neil Smith
-
Publication number: 20120120520Abstract: A CPP spin-valve magnetic head, according to one embodiment includes a ferromagnetic free layer having a bias-point magnetization nominally oriented in a first direction; a ferromagnetic reference layer film having a bias-point magnetization nominally oriented in a second direction that is not orthogonal to the said first direction; and a tunnel barrier layer between the free and reference layers.Type: ApplicationFiled: January 26, 2012Publication date: May 17, 2012Applicant: Hitachi Global Storage Technologies Netherlands, B.V.Inventors: Jeffrey Robinson Childress, Neil Smith
-
Patent number: 8130474Abstract: A TMR sensor structure having free and reference layers, where the magnetic orientations of the free and reference layers are non-orthogonal. In one embodiment, a ferromagnetic free layer film has a bias-point magnetization nominally oriented in plane of the film thereof, in a first direction at an angle ?fb with respect to a longitudinal axis being defined as the intersection of the plane of deposition of the free layer and the plane of the ABS. A ferromagnetic reference layer film has a bias-point magnetization nominally oriented in a plane of the film thereof, in a second direction at angle ?rb with respect to said longitudinal axis that is not orthogonal to the said first direction.Type: GrantFiled: July 14, 2008Date of Patent: March 6, 2012Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Jeffrey Robinson Childress, Neil Smith
-
Patent number: 8004374Abstract: A microwave bandstop filter having a magnetic strip formed over dielectric material. The magnetic resonant frequency is controlled by an induced magnetic anisotropy in the magnetic strip of the microwave bandstop filter. The magnetic anisotropy field is induced by an anisotropic surface texture formed on the surface of the magnetic strip itself, or formed on an underlying layer. Alternatively, the anisotropic surface texture could be formed on both an underlying layer and on the magnetic strip itself. This induced magnetic anisotropy field allows the resonant frequency of the microwave filter to be controlled over a wide frequency range and make high frequency operation possible without reliance on the application of an externally applied magnetic field.Type: GrantFiled: August 27, 2007Date of Patent: August 23, 2011Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Stefan Maat
-
Patent number: 7833388Abstract: A method for manufacturing a magnetic layer with a magnetic anisotropy. The method includes an endpoint detection process for determining an end point to carefully control the final thickness of the magnetic layer. The method includes depositing a magnetic layer and then depositing a sacrificial layer over the magnetic layer. A low power angled ion milling is then performed until the magnetic layer has been reached. The angled ion milling can be performed at an angle relative to normal and without rotation in order to form an anisotropic surface texture that induces a magnetic anisotropy in the magnetic layer. An indicator layer may be included between the magnetic layer and the sacrificial layer in order to further improve endpoint detection.Type: GrantFiled: December 22, 2006Date of Patent: November 16, 2010Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Stefan Maat
-
Patent number: 7791844Abstract: A magnetoresistive sensor having a magnetically stable free layer fabricated from a material having a positive magnetostriction such as a Co—Fe—B alloy. Although the free layer is fabricated from a material that has a positive magnetostriction, which would ordinarily make the free layer unstable, the magnetization of the free layer remains stable because of an induced magnetic anisotropy that has an easy axis of magnetization oriented parallel to the Air-bearing Surface (ABS). This magnetic anisotropy of the free layer is induced by an anisotropic texturing of the surface of the free layer. The resulting anisotropic surface texture is produced by an ion milling process that utilizes an ion beam directed at an acute angle relative to the normal to the surface of the wafer whereon the sensor is fabricated while the wafer is held on a stationary chuck.Type: GrantFiled: April 19, 2007Date of Patent: September 7, 2010Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Stefan Maat, James L. Nix
-
Patent number: 7765675Abstract: Current-perpendicular-to-plane (CPP) read sensors for magnetic heads having constrained current paths made of lithographically-defined conductive vias, and methods of making the same, are disclosed. In one example, a sensor stack structure which includes an electrically conductive spacer layer is formed over a first shield layer. An insulator layer is deposited over and adjacent the spacer layer, and a resist structure which exposes one or more portions of the insulator layer is formed over the insulator layer. With the resist structure in place, the exposed insulator layer portions are removed by etching to form one or more apertures through the insulator layer down to the spacer layer. Electrically conductive materials are subsequently deposited within the one or more apertures to form one or more lithographically-defined conductive vias of a current-constraining structure.Type: GrantFiled: September 1, 2005Date of Patent: August 3, 2010Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Jeffrey Robinson Childress, Jordan Asher Katine
-
Patent number: 7698807Abstract: Formation of the magnetic sensor layers of a magnetic sensor are separated into at least two depositions to reduce the dimension of the sensor. The free layer portion of the sensor is deposited at a different process step than the pinned layer portion. The top of the free layer stack can be a tunnel barrier, the free layer, or part of the free layer. The free layer stack also may contain an in-stack bias layer. The longitudinal bias layer may be patterned in a separate processing step, which allows the stack containing the free layer to be effectively thinner and allow smaller track width dimensions.Type: GrantFiled: January 20, 2006Date of Patent: April 20, 2010Assignee: Hitachi Global Storage Technologies, Netherlands B.V.Inventors: Jeffrey Robinson Childress, Robert E. Fontana, Jr., Jeffrey S. Lille
-
Patent number: 7679866Abstract: A magnetoresistive sensor having a pinned layer that includes a first magnetic layer (AP1) a second magnetic layer (AP2) and an antiparallel coupling layer sandwiched between the AP1 and AP2 layers. The AP1 layer is adjacent to a layer of antiferromagnetic material (AFM layer) and is constructed so as to have a long spin diffusion length. The long spin diffusion length of the AP1 layer minimizes the negative GMR contribution of the AP1 layer, thereby increasing the overall GMR effect of the sensor.Type: GrantFiled: November 21, 2007Date of Patent: March 16, 2010Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Matthew Joseph Carey, Shekar Chandrashekariaih, Stefan Maat, Jeffrey Robinson Childress
-
Patent number: 7672090Abstract: 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: GrantFiled: March 31, 2005Date of Patent: March 2, 2010Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Eric Edward Fullerton, Stefan Maat
-
Patent number: 7649719Abstract: A current perpendicular to plane dual giant magnetoresistive sensor (dual CPP GMR sensor) that prevents spin torque noise while having high dR/R performance. The sensor has a design that maximizes the GMR effect (dR/R) by providing a pinned layer structure that maximizes the positive GMR contribution of the AP2 layer (or magnetic layer closest to the spacer layer) while minimizing the negative GMR contribution of the AP1 layer. The pinned layer structure includes an AP1 layer that includes a thin CoFe layer that is exchange coupled with an IrMn or IrMnCr AFM layer and has two or more Co layers with a spin blocking layer sandwiched between them. The use of the Co layers and the spin blocking layer in the AP1 layer minimizes the negative contribution of the AP1 layer. The AP2 layer has a plurality of CoFe layers with nano-layers such as Cu sandwiched between the CoFe layers.Type: GrantFiled: September 21, 2006Date of Patent: January 19, 2010Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Stefan Maat
-
Patent number: 7558028Abstract: A magnetic head including a CPP GMR read sensor that includes a reference layer, a free magnetic layer and a spacer layer that is disposed between them, where the free magnetic layer and the reference magnetic layer are each comprised of Co2MnX where X is a material selected from the group consisting of Ge, Si, Al, Ga and Sn, and where the spacer layer is comprised of a material selected from the group consisting of Ni3Sn, Ni3Sb, Ni2LiGe, Ni2LiSi, Ni2CuSn, Ni2CuSb, Cu2NiSn, Cu2NiSb, Cu2LiGe and Ag2LiSn. Further embodiments include a dual spin valve sensor where the free magnetic layers and the reference layers are each comprised of Heusler alloys. A further illustrative embodiment includes a laminated magnetic layer structure where the magnetic layers are each comprised of a ferromagnetic Heusler alloy, and where the spacer layers are comprised of a nonmagnetic Heusler alloy.Type: GrantFiled: November 16, 2005Date of Patent: July 7, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Stefan Maat
-
Publication number: 20090168269Abstract: A current perpendicular to plane magnetoresistive sensor having improved resistance amplitude change and reduced spin torque noise. The sensor has an antiparallel coupled pinned layer structure with at least one of the layers of the pinned layer structure includes a high spin polarization material such as Co2FeGe. The sensor can also include an antiparallel coupled free layer.Type: ApplicationFiled: December 28, 2007Publication date: July 2, 2009Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Stefan Maat, Neil Smith
-
Patent number: 7529066Abstract: A magnetoresistive sensor having a magnetic anisotropy induced in one or both of the free layer and/or pinned layer. The magnetic anisotropy is induced by a surface texture formed in the surface of the magnetic layer of either or both of the free layer or pinned layer. The surface texture is formed by a direct, angled ion mill performed on the surface of the magnetic layer while holding the wafer on a stationary chuck. By applying this ion milling technique, the magnetic anisotropy of the pinned layer can be formed in a first direction (eg. perpendicular to the ABS) while the magnetic anisotropy of the free layer can be formed perpendicular to that of the pinned layer (eg. parallel to the ABS).Type: GrantFiled: December 14, 2005Date of Patent: May 5, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Stefan Maat