Patents by Inventor Anup Ghosh Roy

Anup Ghosh Roy 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: 11514934
    Abstract: The present disclosure generally relates to a dual free layer (DFL) two dimensional magnetic recording (TDMR) read head. The read head comprises a first sensor, a first rear hard bias (RHB) structure disposed adjacent to the first sensor, an upper shield disposed over the first sensor and first RHB structure, a lower shield disposed over the upper shield, a second sensor disposed over the lower shield, and a second RHB structure disposed adjacent to the second sensor. A first surface of the first sensor is substantially flush or aligned with a first surface of the first RHB structure. A first surface of the second sensor is substantially flush or aligned with a first surface of the second RHB structure. The upper shield extends linearly from a media facing surface into the read head. The first lower shield is over-milled a greater amount of time than the second lower shield.
    Type: Grant
    Filed: October 27, 2021
    Date of Patent: November 29, 2022
    Assignee: Western Digital Technologies, Inc.
    Inventors: Ming Mao, Chen-Jung Chien, Daniele Mauri, Goncalo Marcos Baião De Albuquerque, Chih-Ching Hu, Anup Ghosh Roy, Yung-Hung Wang
  • Patent number: 10068601
    Abstract: A magnetic read apparatus includes a media-facing surface (MFS), a sensor, a shield structure, a side bias structure, and a shield reference bias structure. The sensor includes a free layer and a nonmagnetic layer. The shield structure includes a shield pinning structure and a shield reference structure between the shield pinning structure and the nonmagnetic layer. The nonmagnetic layer is between the free layer and a shield reference structure. The shield pinning structure includes a pinned moment oriented in a first direction. The shield reference structure includes a reference structure moment weakly coupled with the pinned moment. The side bias structure is adjacent to a side of the free layer and biases the free layer in a first direction parallel to the MFS. The shield reference bias structure is adjacent to the shield reference structure and biases the shield reference structure in a direction opposite to the first direction.
    Type: Grant
    Filed: August 9, 2016
    Date of Patent: September 4, 2018
    Assignee: Western Digital (Fremont), LLC
    Inventors: Shaoping Li, Shihai He, Gerardo A. Bertero, Ming Mao, Yuankai Zheng, Anup Ghosh Roy, Chen-Jung Chien, Zhihong Zhang
  • Patent number: 9812155
    Abstract: A method provides a magnetic read apparatus. A sensor stack is deposited. The read sensor is defined from the stack such that the sensor has sides forming a junction angle of 75 degrees-105 degrees from a sensor bottom. Defining the sensor includes performing a first ion mill at a first angle and a first energy and performing a second ion mill at a second angle greater than the first angle and at a second energy less than the first energy. The first angle is 5 degrees-30 degrees from normal to the top surface. After the first ion mill, less than half of the stack's bottom layer depth remains unmilled. Magnetic bias structure(s) adjacent to the sides may be formed. The magnetic bias structure(s) include a side shielding material having at least one of the saturation magnetization greater than 800 emu/cm3 and an exchange length less than five nanometers.
    Type: Grant
    Filed: November 23, 2015
    Date of Patent: November 7, 2017
    Assignee: WESTERN DIGITAL (FREMONT), LLC
    Inventors: Anup Ghosh Roy, Guanxiong Li, Daniele Mauri, Ming Mao, Goncalo Albuquerque, Savas Gider
  • Patent number: 9190080
    Abstract: A method and system for providing a magnetic transducer is described. The method and system include providing an underlayer, a seed structure, and a magnetically hard layer. The underlayer has a surface. The seed structure resides on the surface and includes an amorphous layer and a seed layer. The amorphous layer wets the surface of the underlayer. The seed layer having a natural growth texture. The magnetically hard layer resides on the seed structure. The seed layer resides between the magnetically hard layer and the amorphous layer. The magnetically hard layer has a desired crystal orientation corresponding to the natural growth texture of the seed layer.
    Type: Grant
    Filed: August 16, 2007
    Date of Patent: November 17, 2015
    Assignee: Western Digital (Fremont), LLC
    Inventors: Anup Ghosh Roy, Xiaozhong Dang
  • Patent number: 8547667
    Abstract: A method and system for providing a magnetic transducer is described. The method and system include providing a seed layer and providing at least one adjustment layer on the seed layer. The method and system also include providing a hard bias structure on the at least one adjustment layer. The seed layer has a first template including a first template dimension and a first texture. The at least one adjustment layer has a second template including a second template dimension and a second texture. The hard bias structure has a third template including a third template dimension and a third texture. The second template is between the first template and the third template.
    Type: Grant
    Filed: November 26, 2008
    Date of Patent: October 1, 2013
    Assignee: Western Digital (Fremont), LLC
    Inventors: Anup Ghosh Roy, Ming Mao, Mahendra Pakala