Patents by Inventor David John Seagle

David John Seagle 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: 20090168259
    Abstract: Embodiments of the invention provide methods, systems and apparatus for testing electronic components, and more specifically for testing magnetoresistive heads. A pair of top shield pads and a pair of bottom shield pads may be formed in a kerf region of a wafer on which magnetoresistive heads are formed. The top shield pads, bottom shield pads, and a magnetoresistive head may form a circuit that may be coupled with a testing circuit to exchange test signals configured to test the magnetic head. The pair of bottom shield pads may provide balanced impedance to substrate that nullifies the effects of broadband noise.
    Type: Application
    Filed: December 31, 2007
    Publication date: July 2, 2009
    Inventors: ARLEY CLEVELAND MARLEY, David John Seagle
  • Patent number: 7545608
    Abstract: A current-perpendicular-to-the-plane (CPP) magnetoresistive (MR) read head structure has the MR read head located between first and second shields (S1, S2) on a substrate with a shunt resistor R1 connecting S1 to the substrate and a shunt resistor R2 connecting S2 to the substrate, with R1 and R2 being approximately equal. Because R1 and R2 are close enough in value there is no significant interference pickup in the low frequency region. The shunt resistors can be formed from high-resistivity metal nitrides or cermets. The spacing between the substrate and S1 may be selected to make the capacitance between S1 and the substrate approximately equal to the capacitance between S2 and the substrate to substantially reduce interference pickup in the high frequency region.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: June 9, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Satoru Araki, John Contreras, Klaas Berend Klaassen, Ramona Marie Patterson, David John Seagle, Howard Gordon Zolla
  • Patent number: 7535674
    Abstract: The structure for a closely spaced, coplanar tape head array is disclosed. Narrow pitch is obtained by utilizing an orthogonal backgap structure, wherein the width of the backgap is less than the depth, thereby narrowing the footprint of individual head structures. The increased cross sectional area of the orthogonal backgap and revised yoke design ensure sufficient magnetic field strength at the write gap of each head.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: May 19, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Edward Hin Pong Lee, David John Seagle
  • Patent number: 7469466
    Abstract: A method of temporarily protecting an electrically sensitive component from damage due to electrostatic discharge is disclosed. The method includes the steps of defining a first shield that forms a first lead for both a component and a shunt; depositing a conductive material on the first shield to form the component and the shunt; defining an edge of the component and an edge of the shunt together in a single masking step; refilling with insulation adjacent the component and the shunt to their respective edges on the first shield; defining a second shield on both the component and the shunt that forms a second lead for both the component and the shunt to form a shunted assembly that electrically protects the component; lapping the shunted assembly; and removing a portion of the shunted assembly to remove the shunt and form an electrical open for an unshunted assembly.
    Type: Grant
    Filed: January 4, 2005
    Date of Patent: December 30, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands BV
    Inventors: Robert Stanley Beach, David John Seagle, Jila Tabib
  • Patent number: 7450340
    Abstract: The structure for a closely spaced, coplanar tape head array is disclosed. Narrow pitch is obtained by utilizing an overlapping coil structure, wherein write coils of adjacent heads overlap. The overlap is made possible by placing coils of adjacent heads at different levels within the thin film structure, separated by dielectric insulating layers.
    Type: Grant
    Filed: November 30, 2004
    Date of Patent: November 11, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Edward Hin Pong Lee, David John Seagle
  • Publication number: 20080186626
    Abstract: A method of fabricating a magnetic head including a CPP read head sensor. The CPP sensor includes a layered sensor stack including a free magnetic layer, a tunnel barrier layer, a pinned magnetic layer and an antiferromagnetic layer. An ion milling process is used to perform a partial depth material removal to establish the back wall of the sensor stack, where the antiferromagnetic layer is not milled through to create the back wall of the sensor stack. ELGs are fabricated during said ion milling process, and in an embodiment the ELGs are disposed at a same level as the tunnel barrier layer and are coplanar therewith.
    Type: Application
    Filed: February 6, 2007
    Publication date: August 7, 2008
    Inventors: Ying Hong, David John Seagle
  • Publication number: 20080144229
    Abstract: An improved magnetic head for a hard disk drive including a lead overlaid read head in which the read width and read gap are reduced. The read width, which corresponds to the distance between the inner ends of the overlaid electrical leads, is reduced by the fabrication of a thin read width insulation member prior to the fabrication of the overlaid electrical leads. The read gap is reduced by fabricating the overlaid electrical leads from a magnetic, electrically conductive material such as NiFe, whereby the overlaid electrical leads also function as a magnetic shield. The read gap, which is the distance between the first and second magnetic shields is thus reduced as compared to the prior art by the thickness of the electrical leads and the thickness of the prior art second insulation layer formed between the electrical leads and the second magnetic shield.
    Type: Application
    Filed: December 14, 2006
    Publication date: June 19, 2008
    Inventors: Kuok San Ho, Edward Hin Pong Lee, David John Seagle, Ching Hwa Tsang
  • Publication number: 20080100970
    Abstract: A current-perpendicular-to-the-plane (CPP) magnetoresistive (MR) read head structure has the MR read head located between first and second shields (S1, S2) on a substrate with a shunt resistor R1 connecting S1 to the substrate and a shunt resistor R2 connecting S2 to the substrate, with R1 and R2 being approximately equal. Because R1 and R2 are close enough in value there is no significant interference pickup in the low frequency region. The shunt resistors can be formed from high-resistivity metal nitrides or cermets. The spacing between the substrate and S1 may be selected to make the capacitance between S1 and the substrate approximately equal to the capacitance between S2 and the substrate to substantially reduce interference pickup in the high frequency region.
    Type: Application
    Filed: October 30, 2006
    Publication date: May 1, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Satoru Araki, John Contreras, Klaas Berend Klaassen, Ramona Marie Patterson, David John Seagle, Howard Gordon Zolla
  • Publication number: 20080088985
    Abstract: A magnetic head including a CPP read head sensor. The CPP sensor includes a layered sensor stack including a free magnetic layer, a tunnel barrier layer, a pinned magnetic layer and an antiferromagnetic layer. An ion milling process is used to perform a partial depth material removal to establish the back wall of the sensor stack. The antiferromagnetic layer is not milled through to create the back wall of the sensor stack. Side walls of the sensor stack may also be created by ion milling, when the antiferromagnetic layer is not milled through in creating the side walls. In various embodiments, the material removal depth lies beyond the tunnel barrier layer, within or even through the pinned magnetic layer.
    Type: Application
    Filed: October 16, 2006
    Publication date: April 17, 2008
    Inventors: Alexander Adrian Girling Driskill-Smith, David John Seagle
  • Patent number: 7349179
    Abstract: A magnetic write head provides a significant write field and minimal adjacent track erasure, and lends itself to improved manufacturability. The write head includes a pedestal throat height that defines a bottom pole, P1, and that is substantially recessed from the air bearing surface. The write head further includes a top pole, P2, that defines a nose that is closer to the air bearing surface than the pedestal zero throat. This design achieves a relatively high ratio of the off-track to on-track field. As an example, a 1:4 ratio could be achieved to significantly mitigate the erasure problem of the adjacent tracks resulting from magnetic flux saturation.
    Type: Grant
    Filed: July 16, 2001
    Date of Patent: March 25, 2008
    Assignee: Western Digital (Fremont), LLC
    Inventors: Qing He, David John Seagle, Loi Dac Pham, Marcos Moises Lederman
  • Patent number: 7054113
    Abstract: A method for manufacturing a reader/writer is provided having a substrate with an undercoat formed thereon. A first shield is formed over a portion of the undercoat and a pair of reader leads is formed over the first shield and undercoat. A read sensor is formed between the reader leads and a first pole/second shield is formed over the reader leads. A mid coat is formed over the undercoat and the reader leads. A second pole is formed over and in contact with the mid coat. A lead is formed over the second pole. A pedestal is formed over the reader lead and an overcoat is formed over the second pole and the lead and around the pedestal. A pad is then formed over the pedestal.
    Type: Grant
    Filed: October 25, 2001
    Date of Patent: May 30, 2006
    Assignee: Western Digital (Fremont), Inc.
    Inventors: David John Seagle, Mark David Thomas, Sandra Sankar, Pei Zou, Carlos Corona
  • Patent number: 7035046
    Abstract: An enhanced recording head design provides thermal diffusion and thermal expansion control in order to minimize the pole tip protrusion resulting from the thermal heating of the magnetic recording head during operation. In one embodiment, the recording head a thermal restraint section formed above a write section, and is made of a 60–80% face-centered-cubic NiFe (Invar) material. According to another embodiment, the thermal restraint section is formed under the read section. According to yet another embodiment, one thermal restraint section is formed above the write section, and another thermal restraint section formed under the read section.
    Type: Grant
    Filed: March 19, 2002
    Date of Patent: April 25, 2006
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Kenneth Frederick Young, David John Seagle
  • Patent number: 6987643
    Abstract: A method and system for providing a pedestal defined zero throat write head is disclosed. The method and system include providing a first pole having a pedestal, a second pole and a gap separating the pedestal of the first pole from a portion of the second pole. The pedestal has a front, a back and a notch. The gap has a first portion and a second portion. The first portion of the gap is in proximity to front of the pedestal. The second portion of the gap is in proximity to the back of the pedestal. The first portion of the gap is thinner than the second portion of the gap.
    Type: Grant
    Filed: October 23, 2001
    Date of Patent: January 17, 2006
    Assignee: Western Digital (Fremont), Inc.
    Inventor: David John Seagle
  • Patent number: 6873499
    Abstract: A read head has a flux guide layer that is immediately adjacent (abuts) the back edge of a read sensor. The flux guide layer is made of a high resistance soft magnetic material that conducts magnetic flux from the back edge of the read sensor so that the magnetic response at the back edge of the read sensor is significantly higher than zero. This increases the efficiency of the read sensor. The material for the flux guide layer is A-B-C where A is selected from the group Fe and Co, B is selected from the group Hf, Y, Ta and Zr and C is selected from the group O and N. In a preferred embodiment A-B-C is Fe—Hf—O and the Ms? of the flux guide layer is greater than 50 times the Ms? of the read sensor layer where the read sensor layer is NiFe, Ms is saturation magnetization and ? is resistivity. Because of the flux guides high resistance current shunting losses are nearly eliminated.
    Type: Grant
    Filed: January 24, 2001
    Date of Patent: March 29, 2005
    Assignee: International Business Machines Corporation
    Inventors: Wen Yaung Lee, Tsann Lin, Daniele Mauri, David John Seagle
  • Publication number: 20010004306
    Abstract: A read head has a flux guide layer that is immediately adjacent (abuts) the back edge of a read sensor. The flux guide layer is made of a high resistance soft magnetic material that conducts magnetic flux from the back edge of the read sensor so that the magnetic response at the back edge of the read sensor is significantly higher than zero. This increases the efficiency of the read sensor. The material for the flux guide layer is A-B-C where A is selected from the group Fe and Co, B is selected from the group Hf, Y, Ta and Zr and C is selected from the group O and N. In a preferred embodiment A-B-C is Fe-Hf-O and the Ms&rgr; of the flux guide layer is greater than 50 times the Ms&rgr; of the read sensor layer where the read sensor layer is NiFe, Ms is saturation magnetization and &rgr; is resistivity. Because of the flux guides high resistance current shunting losses are nearly eliminated.
    Type: Application
    Filed: January 24, 2001
    Publication date: June 21, 2001
    Inventors: Wen Yaung Lee, Tsann Lin, Daniele Mauri, David John Seagle
  • Patent number: 6223420
    Abstract: A read head has a flux guide layer that is immediately adjacent (abuts) the back edge of a read sensor. The flux guide layer is made of a high resistance soft magnetic material that conducts magnetic flux from the back edge of the read sensor so that the magnetic response at the back edge of the read sensor is significantly higher than zero. This increases the efficiency of the read sensor. The material for the flux guide layer is A-B-C where A is selected from the group Fe and Co, B is selected from the group Hf, Y, Ta and Zr and C is selected from the group O and N. In a preferred embodiment A-B-C is Fe—Hf—O and the Ms&rgr; of the flux guide layer is greater than 50 times the Ms&rgr; of the read sensor layer where the read sensor layer is NiFe, Ms is saturation magnetization and &rgr; is resistivity. Because of the flux guides high resistance current shunting losses are nearly eliminated.
    Type: Grant
    Filed: December 4, 1998
    Date of Patent: May 1, 2001
    Assignee: International Business Machines Corporation
    Inventors: Wen Yaung Lee, Tsann Lin, Daniele Mauri, David John Seagle
  • Patent number: 6158108
    Abstract: A magnetic head is provided that has an extremely small first shield layer and first and second leads of a read head that extend from a magnetoresistive (MR) sensor to first and second pads without any vias therebetween. This is accomplished by patterning the first shield layer into its final shape before the first gap layer and subsequent layers are formed. An alumina mask with a recess at the ABS of the size of the first shield layer is formed followed by forming the first shield layer in the recess. A very thin first gap layer and an optional supplemental first gap layer are then formed, the supplemental first gap layer insulating any potential exposure of the first shield layer at its junction with the alumina layer. After constructing the MR sensor, first and second leads for the MR sensor are constructed from the MR sensor to sites of the first and second pads.
    Type: Grant
    Filed: March 30, 1999
    Date of Patent: December 12, 2000
    Assignee: International Business Machines Corporation
    Inventor: David John Seagle
  • Patent number: 6038110
    Abstract: A thin-film magnetic head includes a substrate having first and second magnetic layers disposed above the substrate and formed as a laminated sequence of magnetic sub-layers. The first and second magnetic layers have corresponding first ends representing a pole tip region of the head, corresponding second ends representing a back gap region of the head, and corresponding intermediate portions representing an intermediate region of the head between the pole tip region and the back gap region. The first and second magnetic layers are joined together in physical contact at the back gap region and are spaced from one another at the pole tip region and at the intermediate region. A nonmagnetic gap layer is disposed between the first and second magnetic layers at the pole tip region. A magnetic coil structure is disposed between the first and second magnetic layers at the intermediate region.
    Type: Grant
    Filed: December 6, 1996
    Date of Patent: March 14, 2000
    Assignee: International Business Machines Corporation
    Inventors: Joseph Adam Aboaf, Thomas Beaulieu, Vincent Noel Kahwaty, deceased, Mohamad Towfik Krounbi, David John Seagle
  • Patent number: 6004473
    Abstract: A method is provided wherein first and second sacrificial layers of a write element in a merged magnetic head are provided on top of a coil material layer, wherein the first sacrificial layer serves as a mask for shaping the coil material layer into a write coil, and the second sacrificial layer is employed for patterning the desired shape of the first sacrificial layer. The second sacrificial layer is shaped by a first reactive ion etching (RIE) step through a spiral opening in a photoresist layer. The result is a spiral-shaped second sacrificial layer that is employed as a mask for a second RIE to etch the first sacrificial layer through a spiral opening in the second sacrificial layer.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: December 21, 1999
    Assignee: International Business Machines Corporation
    Inventors: Richard Hsiao, Cherngye Hwang, David John Seagle
  • Patent number: 5936811
    Abstract: A magnetic head is provided that has an extremely small first shield layer and first and second leads of a read head that extend from a magnetoresistive (MR) sensor to first and second pads without any vias therebetween. This is accomplished by patterning the first shield layer into its final shape before the first gap layer and subsequent layers are formed. An alumina mask with a recess at the ABS of the size of the first shield layer is formed followed by forming the first shield layer in the recess. A very thin first gap layer and an optional supplemental first gap layer are then formed, the supplemental first gap layer insulating any potential exposure of the first shield layer at its junction with the alumina layer. After constructing the MR sensor, first and second leads for the MR sensor are constructed from the MR sensor to sites of the first and second pads.
    Type: Grant
    Filed: June 12, 1997
    Date of Patent: August 10, 1999
    Assignee: International Business Machines Corporation
    Inventor: David John Seagle