Patents by Inventor Niraj Mahadev

Niraj Mahadev 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: 20220315802
    Abstract: The present disclosure relates to aqueous suspensions suitable for chemical mechanical planarization (CMP), the use of aqueous suspensions and a method of CMP using aqueous suspensions. The suspensions and method can be used for CMP of silicon carbide surfaces.
    Type: Application
    Filed: March 30, 2022
    Publication date: October 6, 2022
    Inventors: Sridevi R. ALETY, Mark CYFFKA, Niraj MAHADEV
  • Publication number: 20220306902
    Abstract: The present disclosure relates to aqueous suspensions suitable for chemical mechanical planarization (CMP), the use of aqueous suspensions and a method of CMP using aqueous suspensions. The suspensions and method can be used for CMP of silicon carbide surfaces.
    Type: Application
    Filed: March 24, 2022
    Publication date: September 29, 2022
    Inventors: Sridevi R. ALETY, Mark CYFFKA, Niraj MAHADEV
  • Patent number: 7836579
    Abstract: A simple method is provided for protecting slider mounted read/write transducers from electrostatic discharge damage during the manufacture of disk drives. The method involves placing a ball of conducting thermoplastic resin, such as a gold or silver epoxy, between the terminal pads of the transducer and using the ball to shunt the pads to read-head shields and the slider substrate and thence to ground. The epoxy ball is easily applied and easily removed and can be used at different stages in the manufacturing process.
    Type: Grant
    Filed: November 5, 2007
    Date of Patent: November 23, 2010
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Niraj Mahadev, Kazumasa Yasuda, Rudy Ayala
  • Publication number: 20090195919
    Abstract: In a method of fabricating a suspension, a suspension has first and second opposing surfaces and includes a flexure, a load beam, a mounting arm, and traces. The flexure is coupled to a proximal end of the load beam, and the mounting arm is coupled to a distal end of the load beam. The traces are coupled to the flexure. A suspension property to be altered is identified. A value of the unaltered suspension property is measured. An altered value of the suspension property is determined. The flexure, the load beam, or the mounting arm of the suspension, or a combination thereof, is coated with at least one layer of at least one film to alter the identified suspension property from the measured value to the predetermined altered value.
    Type: Application
    Filed: February 1, 2008
    Publication date: August 6, 2009
    Applicant: SAE Magnetics (H.K.) LTD.
    Inventor: Niraj Mahadev
  • Patent number: 7562435
    Abstract: The sensitivity of the ABS shape of a suspension mounted slider to temperature variations can be greatly reduced if the backside of the slider is lapped to a smooth convex contour that is similar to the ABS shape, rather than to a planar shape, prior to mounting the slider on the suspension. When the backside surfaces of sliders are shaped in this manner, the size of changes in the crown height of the ABS shape due to temperature variations are greatly reduced and the ABS shapes are distributed more tightly, thereby increasing disk drive reliability.
    Type: Grant
    Filed: March 24, 2005
    Date of Patent: July 21, 2009
    Assignee: SAE Magnetics (H.K.) Ltd.
    Inventors: Niraj Mahadev, Yugraj S. Aujla
  • Publication number: 20090109568
    Abstract: The sensitivity of the fly height of a HDD (hard disk drive) recording head to temperature variations can be greatly reduced, eliminated or controlled in a manner to enhance HDD performance under various temperature conditions by affixing a thermal element to the HGA (head gimbals assembly) flexure. The thermal element in this invention is a deposited, patterned layer of DLC (diamond-like carbon) that has a coefficient of thermal expansion that is less than that of the stainless steel flexure. As a result of the placement of this thermal element on the flexure, the temperature-induced angular variations of PSA (pitch static attitude) can be made to compensate for temperature-induced changes in the slider crown curvature, thereby reducing or eliminating fly height variations due to temperature.
    Type: Application
    Filed: October 31, 2007
    Publication date: April 30, 2009
    Inventors: Manuel A. Hernandez, Niraj Mahadev, Yugraj S. Aujla, Yen Fu, Nelson Troung, Tai Dang
  • Patent number: 7513820
    Abstract: A system and method for producing micro-texture on a slider substrate using chemical & mechanical polishing techniques is described. In certain embodiments of the present invention, this is accomplished by a method comprising formulating an abrasive slurry solution of predetermined acidity (or pH value), treating a chemical mechanical polishing pad with the abrasive slurry, disposing magnetic heads on the chemical mechanical polishing pad and lapping and grinding the magnetic heads for a predetermined period of time. In certain embodiment of the present invention the lapping and grinding of the magnetic heads are accomplished using an apparatus comprising an abrasive slurry solution of predetermined acidity (pH value), a chemical mechanical polishing pad treated with the abrasive slurry solution, wherein the magnetic heads are attached to a fixture capable of disposing the heads on the chemical mechanical polishing pad.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: April 7, 2009
    Assignee: SAE Magnetics (H.K.) Ltd.
    Inventors: Niraj Mahadev, Winston Jose, Kazumasa Yasuda, Rudy Ayala, Tam Nguyen
  • Patent number: 7455332
    Abstract: The overcoat of a slider (alumina) is recessed relative to the slider ABS by a non-abrasive CMP process sufficiently to prevent thermal protrusion of the overcoat during subsequent slider use in a hard disk drive. The CMP process involves the oscillatory and rotational compressional contact between the ABS surface of the slider and a polymerically pre-treated compliant pad that is sprayed by an aqueous alkali lubricating solution having a pH between about 9 and 10. The overcoat is thereby also softened by the lubricating solution and removed by the compressional contact and no use of abrasives is required.
    Type: Grant
    Filed: November 16, 2005
    Date of Patent: November 25, 2008
    Assignee: SAE Magnetics (HK) Ltd.
    Inventors: Winston Jose, Rudy Ayala, Niraj Mahadev
  • Patent number: 7410410
    Abstract: A system and method are described for manufacturing a lapping plate. Diamond particles are premixed with a metal matrix. The diamond particles are electro-deposited onto the surface of a lapping plate. The lapping plate may have a substrate of hard metal with a soft metal coating. The metal matrix and the lapping plate may be the same metal. The metal matrix may be tin, copper, nickel, or silver. The metal matrix may be an alloy of tin, copper, nickel, or silver. The diamond particles may be between 0.1 and 0.25 microns in size. Multiple uniform layers of the diamond particles and metal matrix may be stacked on the lapping plate.
    Type: Grant
    Filed: October 13, 2005
    Date of Patent: August 12, 2008
    Assignee: SAE Magnetics (H.K.) Ltd.
    Inventors: Niraj Mahadev, Winston Jose, Tai Dang
  • Publication number: 20080066294
    Abstract: A simple method is provided for protecting slider mounted read/write transducers from electrostatic discharge damage during the manufacture of disk drives. The method involves placing a ball of conducting thermoplastic resin, such as a gold or silver epoxy, between the terminal pads of the transducer and using the ball to shunt the pads to read-head shields and the slider substrate and thence to ground. The epoxy ball is easily applied and easily removed and can be used at different stages in the manufacturing process.
    Type: Application
    Filed: November 5, 2007
    Publication date: March 20, 2008
    Inventors: Niraj Mahadev, Kazumasa Yasuda, Rudy Ayala
  • Patent number: 7296336
    Abstract: A simple method is provided for protecting slider mounted read/write transducers from electrostatic discharge damage during the manufacture of disk drives. The method involves placing a ball of conducting thermoplastic resin, such as a gold or silver epoxy, between the terminal pads of the transducer and using the ball to shunt the pads to read-head shields and the slider substrate and thence to ground. The epoxy ball is easily applied and easily removed and can be used at different stages in the manufacturing process.
    Type: Grant
    Filed: May 25, 2004
    Date of Patent: November 20, 2007
    Assignee: SAE Magnetics (H.K.) Ltd.
    Inventors: Niraj Mahadev, Kazumasa Yasuda, Rudy Ayala
  • Publication number: 20070218807
    Abstract: A system and method for producing micro-texture on a slider substrate using chemical & mechanical polishing techniques is described. In certain embodiments of the present invention, this is accomplished by a method comprising formulating an abrasive slurry solution of predetermined acidity (or pH value), treating a chemical mechanical polishing pad with the abrasive slurry, disposing magnetic heads on the chemical mechanical polishing pad and lapping and grinding the magnetic heads for a predetermined period of time. In certain embodiment of the present invention the lapping and grinding of the magnetic heads are accomplished using an apparatus comprising an abrasive slurry solution of predetermined acidity (pH value), a chemical mechanical polishing pad treated with the abrasive slurry solution, wherein the magnetic heads are attached to a fixture capable of disposing the heads on the chemical mechanical polishing pad.
    Type: Application
    Filed: March 16, 2006
    Publication date: September 20, 2007
    Inventors: Niraj Mahadev, Winston Jose, Kazumasa Yasuda, Rudy Ayala, Tam Nguyen
  • Publication number: 20070109686
    Abstract: The overcoat of a slider (alumina) is recessed relative to the slider ABS by a non-abrasive CMP process sufficiently to prevent thermal protrusion of the overcoat during subsequent slider use in a hard disk drive. The CMP process involves the oscillatory and rotational compressional contact between the ABS surface of the slider and a polymerically pre-treated compliant pad that is sprayed by an aqueous alkali lubricating solution having a pH between about 9 and 10. The overcoat is thereby also softened by the lubricating solution and removed by the compressional contact and no use of abrasives is required.
    Type: Application
    Filed: November 16, 2005
    Publication date: May 17, 2007
    Inventors: Winston Jose, Rudy Ayala, Niraj Mahadev
  • Publication number: 20070084132
    Abstract: A system and method are described for manufacturing a lapping plate. Diamond particles are premixed with a metal matrix. The diamond particles are electro-deposited onto the surface of a lapping plate. The lapping plate may have a substrate of hard metal with a soft metal coating. The metal matrix and the lapping plate may be the same metal. The metal matrix may be tin, copper, nickel, or silver. The metal matrix may be an alloy of tin, copper, nickel, or silver. The diamond particles may be between 0.1 and 0.25 microns in size. Multiple uniform layers of the diamond particles and metal matrix may be stacked on the lapping plate.
    Type: Application
    Filed: October 13, 2005
    Publication date: April 19, 2007
    Inventors: Niraj Mahadev, Winston Jose, Tai Dang
  • Patent number: 7189150
    Abstract: A system and method are disclosed for edge blending hard drive head sliders by oscillating abrasive lapping tape across the edges of multiple sliders simultaneously. Lapping tape is inserted between each of a number of head sliders bonded to a edge blending jig of an edge blending assembly. The edge blending assembly is adjusted to cause the lapping tape to partially wrap an edge of each slider. The head sliders are edge blended by the relative movement between the sliders and the lapping tape.
    Type: Grant
    Filed: October 22, 2003
    Date of Patent: March 13, 2007
    Assignee: SAE Magnetics (H.K.) Ltd.
    Inventors: Zhu Jian Zhan, Ryuji Fujii, Quan Bao Wang, Niraj Mahadev, Kazumasa Yasuda
  • Publication number: 20060215323
    Abstract: The sensitivity of the ABS shape of a suspension mounted slider to temperature variations can be greatly reduced if the backside of the slider is lapped to a smooth convex contour that is similar to the ABS shape, rather than to a planar shape, prior to mounting the slider on the suspension. When the backside surfaces of sliders are shaped in this manner, the size of changes in the crown height of the ABS shape due to temperature variations are greatly reduced and the ABS shapes are distributed more tightly, thereby increasing disk drive reliability.
    Type: Application
    Filed: March 24, 2005
    Publication date: September 28, 2006
    Inventors: Niraj Mahadev, Yugraj Aujla
  • Publication number: 20060027542
    Abstract: A method of slider machining is disclosed. A slider may be diced out of a row bar. A jet of clean air may dry the slider. A laser, guided by a jet of water, may micro-grind the periphery of the slider. The edges of the slider and the corners of the leading edge may be rounded to a pre-determined radius. The slider may be cleaned with de-ionized water, then dried in a hot oven.
    Type: Application
    Filed: August 29, 2005
    Publication date: February 9, 2006
    Inventors: Niraj Mahadev, Kazumasa Yasuda, Winston Jose
  • Publication number: 20050264905
    Abstract: ABSTRACT A simple method is provided for protecting slider mounted read/write transducers from electrostatic discharge damage during the manufacture of disk drives. The method involves placing a ball of conducting thermoplastic resin, such as a gold or silver epoxy, between the terminal pads of the transducer and using the ball to shunt the pads to read-head shields and the slider substrate and thence to ground. The epoxy ball is easily applied and easily removed and can be used at different stages in the manufacturing process.
    Type: Application
    Filed: May 25, 2004
    Publication date: December 1, 2005
    Inventors: Niraj Mahadev, Kazumasa Yasuda, Rudy Ayala
  • Publication number: 20050245173
    Abstract: A method of slider machining is disclosed. A slider may be diced out of a row bar. A jet of clean air may dry the slider. A laser, guided by a jet of water, may micro-grind the periphery of the slider. The edges of the slider and the corners of the leading edge may be rounded to a pre-determined radius. The slider may be cleaned with de-ionized water, then dried in a hot oven.
    Type: Application
    Filed: April 28, 2004
    Publication date: November 3, 2005
    Inventors: Niraj Mahadev, Kazumasa Yasuda, Winston Jose
  • Patent number: 6960117
    Abstract: A method of slider machining is disclosed. A slider may be diced out of a row bar. A jet of clean air may dry the slider. A laser, guided by a jet of water, may micro-grind the periphery of the slider. The edges of the slider and the corners of the leading edge may be rounded to a pre-determined radius. The slider may be cleaned with de-ionized water, then dried in a hot oven.
    Type: Grant
    Filed: April 28, 2004
    Date of Patent: November 1, 2005
    Assignee: SAE Magnetics (H.K.) Ltd.
    Inventors: Niraj Mahadev, Kazumasa Yasuda, Winston Jose