Western Digital Assigned Twelve Patents

Storage device detecting lasing threshold of laser by measuring protrusion effect
Western Digital Technologies, Inc., San Jose, CA, has been assigned a patent (9,786,310) developed by Richter, Hans J., Palo Alto, CA, Eaton, Robert E., and Moser, Andreas, San Jose, CA, for a “data storage device detecting lasing threshold of laser by measuring protrusion effect.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a laser configured to heat the disk while writing data to the disk. At least four different laser powers are applied to the laser and a fly height of the head over the disk is measured at each laser power. A lasing threshold power for the laser is detected based on the measured fly heights.”

The patent application was filed on June 6, 2017 (15/615,050).

Storage device detecting minimum stable fly height of head over disk
Western Digital Technologies, Inc., San Jose, CA, has been assigned a patent (9,786,309) developed by Knigge, Bernhard E., San Jose, CA, Kermiche, Noureddine, Dana Point, CA, Eaton, Robert E., and Bhargava, Puneet, San Jose, CA, for a “data storage device detecting minimum stable fly height of a head over a disk.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a fly height actuator, (FHA). A FHA control signal is applied to the FHA, wherein the FHA control signal comprises a DC component and an AC component. A fly height metric is measured representing a fly height of the head over the disk for different levels of the DC component. A modulation amplitude of the fly height metric is detected, and a minimum in the modulation amplitude of the fly height metric is detected.”

The patent application was filed on June 6, 2017 (15/614,939).

Magnetic read apparatus having multiple read sensors
Western Digital, Fremont, LLC , Fremont, CA, has been assigned a patent (9,786,305) developed by Li, Shaoping, San Ramon, CA, He, Shihai, Fremont, CA, Bertero, Gerardo A., Redwood City, CA, Mao, Ming, Dublin, CA, and Zheng, Yuankai, Fremont, CA, for a “magnetic read apparatus having multiple read sensors with reduced sensor spacing usable in two-dimensional magnetic recording applications.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A magnetic read apparatus includes a first sensor, a shield layer, an insulating layer, a shield structure and a second sensor. The shield layer is between the first sensor and the insulating layer. The shield structure is in the down track direction from the insulating layer. The shield structure includes a magnetic seed structure, a shield pinning structure and a shield reference structure. The magnetic seed structure adjoins the shield pinning structure. The shield pinning structure is between the shield reference structure and the magnetic seed structure. The second sensor includes a free layer and a nonmagnetic spacer layer between the shield reference structure and the free layer. The shield reference structure is between the shield pinning structure and the nonmagnetic spacer layer. The shield pinning structure includes a pinned magnetic moment. The shield reference structure includes another magnetic moment weakly coupled with the pinned magnetic moment.”

The patent application was filed on May 12, 2016 (15/152,889).

Providing heat assisted magnetic recording write
Western Digital, Fremont, LLC , Fremont, CA, has been assigned a patent (9,786,304) developed by Tanner, Shawn M., San Jose, CA, Yu, Mingjun, Sunnyvale, CA, Zheng, Min, Milpitas, CA, Lee, Kyung, Fremont, CA, Chen, and Tsung Yuan, San Ramon, CA, for a “method for providing heat assisted magnetic recording write apparatus having a near-field transducer with a sloped nose.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A method for fabricating a near-field transducer, (NFT) for a heat assisted magnetic recording, (HAMR) write apparatus is described. The HAMR write apparatus is coupled with a laser for providing energy and has a media-facing surface, (MFS) configured to reside in proximity to a media during use. The method includes providing a stack on an underlayer. The stack includes an endpoint detection layer, an optical layer and an etchable layer. The optical layer is between the etchable and endpoint detection layers. The etchable layer is patterned to form a mask. A portion of the optical layer is removed. A remaining portion of the optical layer has a bevel at a bevel angle from the MFS location. The bevel angle is nonzero and acute. The NFT is provided such that the NFT has an NFT front surface adjoining the bevel and at the bevel angle from the MFS location.”

The patent application was filed on June 30, 2016 (15/199,540).

Providing thin shields in multiple sensor array
Western Digital, Fremont, LLC , Fremont, CA, has been assigned a patent (9,786,301) developed by Li, Shaoping, San Ramon, CA, Bertero, Gerardo A., Redwood City, CA, Rudy, Steven C., Carmel Valley, CA, He, Shihai, Fremont, CA, Mao, Ming, Dublin, CA, Xi, Haiwen, San Jose, CA, Ganesan, Srikanth, Fremont, CA, Leng, Qunwen, Palo Alto, CA, Yi, Ge, San Ramon, CA, Xiao, Rongfu, Dublin, CA, Liu, Feng, San Ramon, CA, and Wang, Lei, Danville, CA, for a “apparatuses and methods for providing thin shields in a multiple sensor array.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “Apparatuses and methods for providing thin shields in a multiple sensor array are provided. One such apparatus is a magnetic read transducer including a first read sensor, a second read sensor, and a shield assembly positioned between the first read sensor and the second read sensor at an air bearing surface, (ABS) of the magnetic read transducer, the shield assembly including a first shield layer assembly having a first footprint with a first area, and a second shield layer assembly having a second footprint with a second area, where the second area is greater than the first area.”

The patent application was filed on December 2, 2014 (14/557,941).

Perpendicular magnetic recording writer
Western Digital, Fremont, LLC , Fremont, CA, has been assigned a patent (9,779,765) developed by Liu, Feng, San Ramon, CA, Li, Zhanjie, Pleasanton, CA, Luo, Peng, San Ramon, CA,and Bai, Zhigang, Fremont, CA, for a “perpendicular magnetic recording writer having improved performance and wide area track erasure reliability.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A magnetic writer includes a high magnetic moment write pole layer on a main write pole, the write pole layer including a proximal end recessed from the air bearing surface, and a Wide Area Track Erasure, (WATER) reservoir recessed from the proximal end of the write pole layer and transverse to a longitudinal direction of the main write pole. The write pole layer may be conformal in shape to, but have smaller dimensions relative to, the main write pole, such that a distance between their outer surfaces is generally constant in a flare region. The WATER reservoir width, in a cross-track direction, may be greater than or equal to the maximum width of the main write pole.”

The patent application was filed on August 24, 2016 (15/245,850).

Magnetic writer having convex trailing surface pole and conformal write gap
Western Digital, Fremont, LLC , Fremont, CA, has been assigned a patent (9,767,831) developed by Pan, Yu, Fremont, CA, Wang, Yugang, Milpitas, CA, Bai, Zhigang, Fremont, CA, Lin, Tao, San Jose, CA, and Zhao, Peng, San Ramon, CA, for a “magnetic writer having convex trailing surface pole and conformal write gap.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A magnetic write apparatus has a media-facing surface, (MFS), a pole, a write gap, a top shield and coil(s). The pole includes a yoke and a pole tip. The pole tip includes a bottom, a top wider than the bottom and first and second sides. The pole tip has a height between the top and the bottom. At least part of the top of the pole tip is convex in a cross-track direction between the first and second sides such that the height at the MFS is larger between the first and second sides than at the first and second sides. The height increases in a yoke direction perpendicular to the MFS. The write gap is adjacent to and conformal with the top of the pole at the MFS and is between part of the top shield and the pole. The top shield is concave at the MFS.”

The patent application was filed on December 1, 2015 (14/956,168).

Heat assisted magnetic recording writer having pole coupled with NFT
Western Digital, Fremont, LLC , Fremont, CA, has been assigned a patent (9,747,935) developed by Stipe, Barry, San Jose, CA, Wang, Yi, Mountain View, CA, Bai, Zhigang, Fremont, CA, and Burgos, Stanley, Campbell, CA, for a “heat assisted magnetic recording writer having pole coupled with the NFT.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A heat assisted magnetic recording, (HAMR) write apparatus has a media-facing surface, (MFS) and is coupled with a laser that provides energy. The HAMR write apparatus includes a waveguide, a near-field transducer, NFT, a pole and coil(s) for energizing the pole. The waveguide is optically coupled with the laser and directs a first portion of the energy toward the MFS. The NFT is optically coupled with the waveguide. The pole writes to a region of the media and includes a pole tip. A first portion of the pole tip is at the MFS and is separated from the NFT in a down track direction. A second portion of the pole tip is recessed from the MFS and between the first portion and the NFT.”

The patent application was filed on June 30, 2016 (15/199,034).

Coat NFT area with highly thermal conducting material in HAMR structure
Western Digital Technologies, Inc., San Jose, CA, has been assigned a patent (9,747,929) developed by Torres, Eduardo, Hwang, Cherngye, and Simmons, Randy, San Jose, CA, for a “method to coat NFT area with highly thermal conducting material in HAMR structure.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “Embodiments disclosed herein generally relate to a method for forming a HAMR head. The method includes depositing a drop-on-demand mask on a portion of a surface of a slider using a drop-on-demand tool. The surface of the slider includes at least a portion of an NFT. A first protective layer is deposited over a remaining portion of the surface of the slider and over the drop-on-demand mask. The drop-on-demand mask and a portion of the first protective layer disposed on the drop-on-demand mask are removed, exposing at least the portion of the NFT. A second protective layer is deposited on the first protective layer and at least the exposed portion of the NFT. By using the drop-on-demand tool to deposit the drop-on-demand mask, the alignment between the drop-on-demand mask and the portion of the NFT is less stringent, and the drop-on-demand mask can be easily removed using a wiping tool.”

The patent application was filed on September 29, 2016 (15/280,071).

Storage device modifying write operation when laser mode hop is detected
Western Digital Technologies, Inc., San Jose, CA, has been assigned a patent (9,747,928) developed by Ruan, Huanxiang, Irvine, CA, Chia, Galvin, Balasubramaniam, Prakash, Rancho Santa Margarita, CA, Haralson, Phillip S., Huntington Beach, CA, and Hogg, Dennis W., Laguna Hills, CA, for a “data storage device modifying write operation when a laser mode hop is detected.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A data storage device is disclosed comprising a first head actuated over a first disk surface, wherein the first head comprises a laser configured to heat the first disk surface while writing data to the first disk surface. A write power is applied to the laser when executing a first write operation, and the first write operation is paused when a transient increase in the output power of the laser is detected. In another embodiment, a write-verify of the written data is executed when a transient decrease in the output power of the laser is detected.”

The patent application was filed on September 25, 2014 (14/497,285).

Read sensor having insulating layer capable
of use in two-dimensional magnetic recording
Western Digital, Fremont, LLC, Fremont, CA, has been assigned a patent (9,715,889) developed by Li, Shaoping, San Ramon, CA, Bertero, Gerardo A., Redwood City, CA, Mao, Ming, Dublin, CA, He, Shihai, Fremont, CA, Rudy, Steven C., Carmel Valley, CA, Xi, Haiwen, San Jose, CA, Li, Zhipeng, Fremont, CA, Wang, Haifeng, Fang, Jianxin, San Jose, CA, Zhang, Zhihong, Fremont, CA, Zhang, Yingbo, San Ramon, CA, Leng, Qunwen, Palo Alto, CA, Beaudry, Christopher L., and Liu, Ruisheng, San Jose, CA, for a “read sensor having an insulating layer capable of use in two-dimensional magnetic recording.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A magnetic read apparatus has a media-facing surface, (MFS) and includes a read sensor, a magnetic bias structure and an insulating layer. The read sensor has a side, a front occupying part of the MFS and a back. The read sensor includes a free layer, a pinned layer and a barrier layer between the free and pinned layers. The barrier layer has a barrier layer coefficient of thermal expansion. The magnetic bias structure is adjacent to the side of the free layer. The insulating layer includes first and second portions. The first portion of the insulating layer is between the read sensor side and the magnetic bias structure. The second portion of the insulating layer adjoins the read sensor back. The insulating layer has an insulating layer coefficient of thermal expansion that is at least 1/3 of and not more than 5/3 of the barrier layer coefficient of thermal expansion.”

The patent application was filed on August 18, 2016 (15/240,311).

Heat assisted magnetic recording write apparatus having inverse tapered waveguide
Western Digital, Fremont, LLC, Fremont, CA, has been assigned a patent (9,697,854) developed by Morelli, Michael V., San Jose, CA, and Sochava, Sergei, Sunnyvale, CA, for a “heat assisted magnetic recording write apparatus having an inverse tapered waveguide.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: A heat assisted magnetic recording, (HAMR) write apparatus has a media-facing surface, (MFS) and includes a pole, coil(s) and a waveguide. The waveguide is optically coupled with a laser and directs energy toward the MFS. The waveguide includes an entrance, a bottom and a mode converter having a core, an inner cladding, high index layer(s) and an outer cladding. The core has sides that diverge in width. The core has a first index of refraction. The outer cladding has a second index of refraction less than the first index of refraction. The inner cladding has a third index of refraction not greater than the second index of refraction. The inner cladding is between the high index layer(s) and the core. The high index layer(s) are between the inner and outer cladding. The high index layer(s) have a high index of refraction greater than the second index of refraction.”

The patent application was filed on July 21, 2016 (15/216,639).