Embodiments of the present disclosure generally relate to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head.
Over the past few years, microwave assisted magnetic recording (MAMR) has been studied as a recording method to improve the areal density of a magnetic read/write device, such as a hard disk drive (HDD). MAMR enabled magnetic recording heads utilize a MAMR stack disposed between the trailing shield and the main pole to improve write field and/or field gradient, leading to better areal density capability (ADC). The MAMR stack may include a seed layer and at least one magnetic layer, such as a spin torque layer (STL) that is magnetized by a bias current from the main pole to the MAMR stack during operation. Alternatively, the MAMR stack may be a spin torque oscillator (STO) for generating a microwave (high frequency AC magnetic field). When a bias current is conducted to the STO from the main pole, the STO oscillates and provides an AC magnetic field to the recording medium. The AC magnetic field may reduce the coercive force of the recording medium, thus high quality recording by MAMR may be achieved.
However, Joule heating induced by the bias current from the main pole to the MAMR stack leads to heating or break-down induced failures. Conventionally, the MAMR stack and the main pole are surrounded by an electrically and thermally resistive material, such as aluminum oxide, which is very inefficient to dissipate heat.
Therefore, there is a need in the art for an improved data storage device.
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 trailing shield, a main pole, a MAMR stack disposed between the trailing shield and the main pole, side shields surrounding at least a portion of the main pole, and a structure disposed between the side shields and the main pole at a media facing surface (MFS). The structure is fabricated from a material that is thermally conductive and electrically insulating/dissipative. The material has a thermal conductivity of at least 50 W/(m*K) and an electrical resistivity of at least 105 Ω*m. The structure helps dissipate joule heating generated from either the main pole or the MAMR stack into surrounding area without electrical shunting, leading to reduced heating or break-down induced failures.
In one embodiment, the magnetic recording head includes a trailing shield, a main pole, a stack disposed between the main pole and the trailing shield, and a first structure surrounding at least a portion of the main pole at a media facing surface, wherein the first structure is fabricated from a material having a thermal conductivity of at least 50 W/(m*K) and an electrical resistivity of at least 105 Ω*m.
In another embodiment, the magnetic recording head includes a trailing shield, a main pole, a stack disposed between the main pole and the trailing shield, and a first structure surrounding at least a portion of the main pole at a media facing surface, wherein the first structure is fabricated from a material selected from the group consisting of aluminum nitride, silicon carbide, beryllium oxide, gallium nitride, gallium phosphide, hexagonal boron nitride, cubic boron nitride, boron arsenide, gamma magnesium aluminate, zinc oxide, silicon, carbon, beryllium, tungsten, iridium, rhodium, molybdenum, diamond like carbon, and combination thereof.
In another embodiment, the magnetic recording head includes a trailing shield, a main pole, side shields surrounding at least a portion of the main pole, a stack disposed between the main pole and the trailing shield, and a first structure disposed between the trailing shield and the side shields, wherein the first structure includes at least one layer of gallium nitride, gallium phosphide, hexagonal boron nitride, cubic boron nitride, boron arsenide, gamma magnesium aluminate, silicon, carbon, beryllium, tungsten, iridium, rhodium, molybdenum, diamond like carbon, or zinc oxide, and at least one layer of aluminum oxide, aluminum nitride, or silicon carbide.
In another embodiment, the magnetic recording head includes a trailing shield, a main pole, a stack disposed between the main pole and the trailing shield, and means for dissipate heat generated from the main pole or the stack without electrical shunting, wherein the means for dissipate heat surrounds at least a portion of the main pole at a media facing surface.
So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure may admit to other equally effective embodiments.
To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one embodiment may be beneficially utilized on other embodiments without specific recitation.
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 trailing shield, a main pole, a MAMR stack disposed between the trailing shield and the main pole, side shields surrounding at least a portion of the main pole, and a structure disposed between the side shields and the main pole at a MFS. The structure is fabricated from a material that is thermally conductive and electrically insulating/dissipative. The material has a thermal conductivity of at least 50 W/(m*K) and an electrical resistivity of at least 105 Ω*m. The structure helps dissipate joule heating generated from either the main pole or the MAMR stack into surrounding area without electrical shunting, leading to reduced heating or break-down induced failures.
The terms “over,” “under,” “between,” and “on” as used herein refer to a relative position of one layer with respect to other layers. As such, for example, one layer disposed over or under another layer may be directly in contact with the other layer or may have one or more intervening layers. Moreover, one layer disposed between layers may be directly in contact with the two layers or may have one or more intervening layers. In contrast, a first layer “on” a second layer is in contact with the second layer. Additionally, the relative position of one layer with respect to other layers is provided assuming operations are performed relative to a substrate without consideration of the absolute orientation of the substrate.
At least one slider 113 is positioned near the magnetic disk 112, each slider 113 supporting one or more magnetic head assemblies 121. As the magnetic disk 112 rotates, the slider 113 moves radially in and out over the disk surface 122 so that the magnetic head assembly 121 may access different tracks of the magnetic disk 112 where desired data are written. Each slider 113 is attached to an actuator arm 119 by way of a suspension 115. The suspension 115 provides a slight spring force which biases the slider 113 toward the disk surface 122. Each actuator arm 119 is attached to an actuator means 127. The actuator means 127 as shown in
During operation of the disk drive 100, the rotation of the magnetic disk 112 generates an air bearing between the slider 113 and the disk surface 122 which exerts an upward force or lift on the slider 113. The air bearing thus counter-balances the slight spring force of suspension 115 and supports slider 113 off and slightly above the disk surface 122 by a small, substantially constant spacing during normal operation.
The various components of the disk drive 100 are controlled in operation by control signals generated by control unit 129, such as access control signals and internal clock signals. Typically, the control unit 129 comprises logic control circuits, storage means and a microprocessor. The control unit 129 generates control signals to control various system operations such as drive motor control signals on line 123 and head position and seek control signals on line 128. The control signals on line 128 provide the desired current profiles to optimally move and position slider 113 to the desired data track on disk 112. Write and read signals are communicated to and from write and read heads on the assembly 121 by way of recording channel 125.
The above description of a typical magnetic media device and the accompanying illustration of
In some embodiments, the magnetic read head 211 is a magnetoresistive (MR) read head that includes an MR sensing element 204 disposed between MR shields S1 and S2. In other embodiments, the magnetic read head 211 is a magnetic tunnel junction (MTJ) read head that includes a MTJ sensing device 204 disposed between MR shields S1 and S2. The magnetic fields of the adjacent magnetized regions in the magnetic disk 202 are detectable by the MR (or MTJ) sensing element 204 as the recorded bits.
The write head 210 includes a main pole 220, a leading shield 206, a trailing shield 240, a MAMR stack 230 disposed between the main pole 220 and the trailing shield 240, and a coil 218 that excites the main pole 220. The coil 218 may have a “pancake” structure which winds around a back-contact between the main pole 220 and the leading shield 206, instead of a “helical” structure shown in
The structure 254 is fabricated from a material that is thermally conductive and electrically insulating/dissipative. The material has a thermal conductivity of at least 50 W/(m*K) and an electrical resistivity of at least 105 Ω*m. The structure 254 helps dissipate joule heating generated from either the main pole 220 or the MAMR stack 230 into surrounding area without electrical shunting, leading to reduced heating or break-down induced failures. In one embodiment, the structure 254 is fabricated from aluminum nitride (AlN), silicon carbide (SiC), beryllium oxide (BeO), gallium nitride (GaN), gallium phosphide (GaP), hexagonal boron nitride (h-BN), cubic boron nitride (c-BN), boron arsenide (B2As12), gamma magnesium aluminate (γ-MgAl2O4), zinc oxide (ZnO), silicon (Si), carbon (C), beryllium (Be), tungsten (W), iridium (Ir), rhodium (Rh), molybdenum (Mo), diamond like carbon (DLC), or combination thereof. In one embodiment, the structure 254 is a multi-layer structure including at least one layer of GaN, GaP, h-BN, c-BN, B2As12, γ-MgAl2O4, ZnO, Si, C, Be, W, Ir, Rh, Mo, or DLC, and at least one layer of aluminum oxide (Al2O3), AlN, or SiC. In addition to having good thermal conductivity, materials, such as C, Be, W, Ir, and Mo, having high melting point, such as greater than 1500 K, are less prone to thermal degradation due to diffusion or oxidation during operation. In one embodiment, the structure 254 includes at least a first layer fabricated from C, Be, W, Ir, Rh, or Mo, and at least a second layer fabricated from Al2O3, AlN, or SiC. In one embodiment, the structure 254 includes a Si layer and an Al2O3 layer. In one embodiment, the structure 254 is a single layer that is a mixture of two or more materials including GaN, GaP, h-BN, c-BN, B2As12, γ-MgAl2O4, ZnO, Si, DLC, Al2O3, AlN, C, Be, W, Ir, Rh, Mo, and SiC. The single layer having two or more materials may be formed by a sputtering process that co-sputters two or more targets, or other processes that are known by the skilled in the art.
The main pole 220 includes a trailing taper 242 and a leading taper 244. The trailing taper 242 extends from a location recessed from the MFS 212 to the MFS 212. The leading taper 244 extends from a location recessed from the MFS 212 to the MFS 212. The trailing taper 242 and the leading taper 244 may have the same degree of taper, and the degree of taper is measured with respect to a longitudinal axis 260 of the main pole 220. In some embodiments, the main pole 220 does not include the trailing taper 242 and the leading taper 244. Instead, the main pole 220 includes a trailing side (not shown) and a leading side (not shown), and the trailing side and the leading side are substantially parallel. The main pole 220 may be a magnetic material such as a FeCo or FeCo(N) alloy, or bct-Fe16N2. The leading shield 206 and the trailing shield 240 may be a magnetic material, such as NiFe alloy.
The MAMR stack 230 is disposed on both the main pole 220 and the non-magnetic electrically conductive structure 246, so the electric current can flow to the MAMR stack 230 from the main pole 220 and the non-magnetic electrically conductive structure 246. A structure 306 is disposed between the trailing shield 240 and the side shields 302. In one embodiment, the structure 306 is in contact with the trailing shield 240 and the side shields 302. The structure 306 is fabricated from a material that is thermally conductive and electrically insulating/dissipative. The material has a thermal conductivity of at least 50 W/(m*K) and an electrical resistivity of at least 105 Ω*m. In one embodiment, the structure 306 is fabricated from the same material as the structure 254. In one embodiment, the structure 306 is fabricated from a different material from the structure 254. The structure 306 includes first portions 308 at the MFS 212, and the MAMR stack 230 is disposed between the first portions 308 of the structure 306 at the MFS 212. Each of the first portions 308 of the structure 306 has a thickness t2. The thickness t2 ranges from about the same as the thickness of the MAMR stack 230 to about 1.5 times the thickness of the MAMR stack 230. The thickness t2 is substantially greater than the thickness t1. In one embodiment, the first portions 308 of the structure 306 are in contact with the MAMR stack 230. The first portions 308 of the structure 306 are in contact with the structure 254, as shown in
As shown in
The data storage device including the magnetic write head having a heat dissipating structure surrounding at least a portion of the main pole and another heat dissipating structure in contact with the MAMR stack. The heat dissipating structures are both electrically insulating/dissipative. Joule heating generated in the main pole and the MAMR stack is dissipated by the structures. As a result, the write-ability of the magnetic write head is improved, and the life-time of the magnetic write head is increased because failures induced by heating or break-down are minimized.
While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
This application is a divisional of co-pending U.S. patent application Ser. No. 16/276,508, filed Feb. 14, 2019, which claims benefit of continuation of co-pending U.S. patent application Ser. No. 16/146,139, filed Sep. 28, 2018, which claims benefit of U.S. Provisional Patent Application Ser. No. 62/607,757, filed Dec. 19, 2017. Each of the aforementioned related patent applications is herein incorporated by reference.
Number | Name | Date | Kind |
---|---|---|---|
5966273 | Matsumoto et al. | Oct 1999 | A |
6252749 | Hayakawa | Jun 2001 | B1 |
6396660 | Jensen et al. | May 2002 | B1 |
6950280 | Rea et al. | Sep 2005 | B2 |
7239478 | Sin | Jul 2007 | B1 |
8325442 | Koui et al. | Dec 2012 | B2 |
8582240 | Chen et al. | Nov 2013 | B1 |
8861137 | Lam et al. | Oct 2014 | B1 |
8995088 | Boone et al. | Mar 2015 | B1 |
9135933 | Nunokawa et al. | Sep 2015 | B2 |
9230571 | Chen et al. | Jan 2016 | B1 |
9275672 | Shiroishi et al. | Mar 2016 | B2 |
9368135 | Gao | Jun 2016 | B2 |
9508364 | Tang et al. | Nov 2016 | B1 |
9691416 | Izawa et al. | Jun 2017 | B1 |
9881637 | Wilson et al. | Jan 2018 | B1 |
10121497 | Takahashi et al. | Nov 2018 | B1 |
10147446 | Wessel et al. | Dec 2018 | B1 |
10186284 | Narita et al. | Jan 2019 | B2 |
10236021 | Narita et al. | Mar 2019 | B2 |
10276193 | Narita et al. | Apr 2019 | B2 |
10325618 | Wu et al. | Jun 2019 | B1 |
10366714 | Olson et al. | Jul 2019 | B1 |
10636439 | Le | Apr 2020 | B2 |
20030067717 | Garfunkel et al. | Apr 2003 | A1 |
20040085675 | Cyrille et al. | May 2004 | A1 |
20080244896 | Bonhote | Oct 2008 | A1 |
20080291582 | Hirata et al. | Nov 2008 | A1 |
20080304176 | Takagishi et al. | Dec 2008 | A1 |
20090059423 | Yamada et al. | Mar 2009 | A1 |
20090310244 | Shimazawa et al. | Dec 2009 | A1 |
20090316304 | Funayama et al. | Dec 2009 | A1 |
20120113544 | Bonhote et al. | May 2012 | A1 |
20120170156 | Sasaki et al. | Jul 2012 | A1 |
20130057981 | Urakami et al. | Mar 2013 | A1 |
20130063837 | Udo et al. | Mar 2013 | A1 |
20130082787 | Zhang | Apr 2013 | A1 |
20130250456 | Yamada et al. | Sep 2013 | A1 |
20130316088 | Fujita et al. | Nov 2013 | A1 |
20140139952 | Takeo et al. | May 2014 | A1 |
20140177100 | Sugiyama et al. | Jun 2014 | A1 |
20150206550 | Freitag et al. | Jul 2015 | A1 |
20160027455 | Kudo et al. | Jan 2016 | A1 |
20170236537 | Murakami et al. | Aug 2017 | A1 |
20180268848 | Narita et al. | Sep 2018 | A1 |
20190088274 | Narita et al. | Mar 2019 | A1 |
20190251991 | Le | Aug 2019 | A1 |
20190259413 | Le | Aug 2019 | A1 |
20200005815 | Bai | Jan 2020 | A1 |
Number | Date | Country |
---|---|---|
104835510 | Nov 2017 | CN |
2013251042 | Dec 2013 | JP |
2015126326 | Aug 2015 | WO |
Entry |
---|
Tagawa et al. “Advantage of MAMR Read-Write Performance,” IEEE Transactions on Magnetics, vol. 52, No. 9; http://www.ieee.org/publications_standards/publications/rights/index.html; Sep. 2016 (4 pages). |
International Search Report and the Written Opinion of the International Application No. PCT/US2018/053223 dated Jan. 28, 2019. |
Mallary, Mike et al.; “Head and Media Challenges for 3 Tb/in2 Microwave-Assisted Magnetic Recording”, IEEE Transactions on Magnetics, vol. 50, No. 7, Jul. 2014 (8 pages). |
Azom “Aluminum Nitride / Aluminum Nitride (AIN)—Properties and Applications,” AZO Materials, published Jul. 26, 2001; https://www.azom.com/article.aspx?ArticleID=610 (Year:2001). |
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20200227075 A1 | Jul 2020 | US |
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62607757 | Dec 2017 | US |
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