# US 10,872,626 B2 · MAMR stack shape optimization for magnetic recording > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,872,626 B2 - Document ID: US10872626B2 - Status: Granted - Kind: B2 - Application number: 16/293,481 - Filed: 2019-03-05 - Published: 2019-10-17 - Granted: 2020-12-22 - Earliest claimed: 2018-03-06 - Assignees: Western Digital Technologies, Inc. - Applicants: Western Digital Technologies, Inc. - Inventors: Venkatesh Chembrolu; Muhammad Asif Bashir; Petrus Antonius Van Der Heijden; Terence Lam; Yaguang Wei - Web page: https://patentgrep.com/patent/US10872626B2 ## CPC - G11B 5/3116: {Shaping of layers, poles or gaps for improving the form of the electrical signal transduced, e.g. for shielding, contour effect, equalizing, side flux fringing, cross talk reduction between heads or between heads and information tracks (G11B5/3113, G11B5/245 take precedence)} - G11B 5/3146: {magnetic layers} - G11B 2005/0024: {Microwave assisted recording} - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) ## Abstract The present disclosure generally relates to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head. The head includes a main pole, a trailing shield, and a MAMR stack including at least one magnetic layer. The magnetic layer has a surface facing the main pole, and the surface has a first side at a media facing surface (MFS) and a second side opposite the first side. The length of the second side is substantially less than the length of the first side. By reducing the length of the second side, the area to be switched at a location recessed from the MFS is reduced as a current flowing from the main pole to the trailing shield or from the trailing shield to the main pole. With the reduced area of the magnetic layer, the overall switch time of the magnetic layer is decreased. ## Claims ### Claim 1 A magnetic recording head, comprising: a trailing shield; a main pole; and a stack disposed between the trailing shield and the main pole at a media facing surface, wherein the stack comprises at least a layer having a first surface at the media facing surface and a second surface opposite the first surface, wherein an area of the second surface of the layer is less than an area of the first surface, and wherein the layer is disposed between and in contact with a seed layer and a spacer layer. ### Claim 2 (depends on 1) The magnetic recording head of claim 1, wherein the layer is a magnetic layer. ### Claim 3 (depends on 2) The magnetic recording head of claim 2, wherein the magnetic layer comprises NiFe, CoMnGe, CoFe, or combinations thereof. ### Claim 4 (depends on 2) The magnetic recording head of claim 2, wherein the first surface and the second surface are both rectangular. ### Claim 5 (depends on 1) The magnetic recording head of claim 1, wherein the layer further comprises a third surface connecting the first surface and the second surface, wherein the third surface faces the main pole. ### Claim 6 (depends on 5) The magnetic recording head of claim 5, wherein the third surface has a trapezoidal shape. ### Claim 7 (depends on 6) The magnetic recording head of claim 6, wherein the third surface has an acute trapezoidal shape, right trapezoidal shape, obtuse trapezoidal shape, or isosceles trapezoidal shape. ### Claim 8 (depends on 1) A data storage device comprising the magnetic recording head of claim 1. ### Claim 9 (depends on 1) The magnetic recording head of claim 1, wherein the layer, the seed layer, and the spacer layer each has substantially a same height from the media facing surface extending into the magnetic recording head. ### Claim 10 (depends on 1) The magnetic recording head of claim 1, the seed layer and the spacer layer each has a same shape as the layer. ### Claim 11 (depends on 1) The magnetic recording head of claim 1, wherein the seed layer comprises Ta, Cr, Cu, NiAl, Ru, Rh, or a combination thereof, and the spacer layer comprises Cu or AgSn. ### Claim 12 (depends on 1) The magnetic recording head of claim 1, wherein the layer has a stripe height from the first surface to the second surface of about 60 nm to about 120 nm. ### Claim 13 (depends on 1) The magnetic recording head of claim 1, wherein the layer further comprises a third surface connecting the first surface and the second surface, wherein the third surface comprises a first side, a second side opposite to the first side, a third side connected to the second side, a fourth side opposite the third side, a fifth side connected to the third side, and a sixth side opposite to the fifth side. ### Claim 14 (depends on 13) The magnetic recording head of claim 13, wherein the first side of the third surface is parallel to the second side of the third surface, and the fifth side of the third surface is parallel to the sixth side of the third surface. ### Claim 15 (depends on 13) The magnetic recording head of claim 13, wherein the third side of the third surface forms a first angle with respect to a central axis of the third surface, and the fourth side of the third surface forms a second angle with respect to the central axis of the third surface. ### Claim 16 (depends on 15) The magnetic recording head of claim 15, wherein the first angle is about 5 degrees to about 60 degrees, and the second angle is about 5 degrees to about 60 degrees. ### Claim 17 (depends on 15) The magnetic recording head of claim 15, wherein the third surface is substantially symmetric with respect to the central axis. ### Claim 18 (depends on 1) The magnetic recording head of claim 1, wherein the layer further comprises a third surface connecting the first surface and the second surface, and a fourth surface opposite the third surface. ### Claim 19 (depends on 18) The magnetic recording head of claim 18, wherein the third surface of the layer faces the trailing shield and the fourth surface of the layer faces the main pole. ### Claim 20 (depends on 1) The magnetic recording head of claim 1, wherein the layer is a spin torque layer. ### Claim 21 A magnetic recording head, comprising: a trailing shield; a main pole; and a stack disposed between the trailing shield and the main pole at a media facing surface, wherein the stack comprises at least a layer, the layer comprising: a first surface at the media facing surface; a second surface opposite the first surface, wherein an area of the second surface of the layer is less than an area of the first surface; and a third surface connecting the first surface and the second surface, wherein the third surface comprises a first side, a second side opposite to the first side, a third side connected to the second side, a fourth side opposite the third side, a fifth side connected to the third side, and a sixth side opposite to the fifth side. ### Claim 22 (depends on 21) The magnetic recording head of claim 21, wherein the first side of the third surface is parallel to the second side of the third surface, and the fifth side of the third surface is parallel to the sixth side of the third surface. ### Claim 23 (depends on 21) The magnetic recording head of claim 21, wherein the third side of the third surface forms a first angle with respect to a central axis of the third surface, and the fourth side of the third surface forms a second angle with respect to the central axis of the third surface. ### Claim 24 (depends on 23) The magnetic recording head of claim 23, wherein the first angle is about 5 degrees to about 60 degrees, and the second angle is about 5 degrees to about 60 degrees. ### Claim 25 (depends on 23) The magnetic recording head of claim 23, wherein the third surface is substantially symmetric with respect to the central axis. ### Claim 26 (depends on 21) A data storage device comprising the magnetic recording head of claim 21. ### Claim 27 A magnetic recording head, comprising: a trailing shield; a main pole; and a stack disposed between the trailing shield and the main pole at a media facing surface, wherein the stack comprises at least a layer, the layer comprising: a first surface at the media facing surface; a second surface opposite the first surface, wherein an area of the second surface of the layer is less than an area of the first surface; a third surface connecting the first surface and the second surface; and a fourth surface opposite the third surface. ### Claim 28 (depends on 27) The magnetic recording head of claim 27, wherein the third surface of the layer faces the trailing shield and the fourth surface of the layer faces the main pole. ### Claim 29 (depends on 27) The magnetic recording head of claim 27, wherein the first surface has a first length and the second surface has a second length that is about one percent to about 90 percent of the first length. ### Claim 30 (depends on 27) A data storage device comprising the magnetic recording head of claim 27.