Local and non-local spin-orbit torque (SOT) write head using topological isolation material

Abstract

To provide a magnetic head with improved spintronic devices.SOLUTION: The present invention relates to a magnetic recording head having a local or non-local SOT spintronic device for a magnetic medium, such as a magnetic media drive. In the case of the magnetic recording head having a local SOT spintronic device, a main pole, a shield, a buffer layer disposed on the main pole, a spin Hall layer disposed on the buffer layer, and an intermediate layer disposed on the spin Hall layer are included, and the buffer layer is made of a predetermined material. In the case of the magnetic recording head 1300 having a non-local SOT spintronic device, a main magnetic pole 1302, a shield 1304, a spin blocking layer 1310, a non-magnetic layer, and a spin-orbit-torque (SOT) layer 1308 are included, and the SOT layer is recessed from a medium facing surface (MFS) by a distance of about 20 nm to about 100 nm. The ratio of the length of the SOT layer to the thickness of the SOT layer is greater than 1. The SOT layer consists of BiSb.SELECTED DRAWING: Figure 10A

Description

[Technical field]

[0001] SUMMARY OF THE DISCLOSURE Embodiments of the present disclosure generally relate to magnetic recording heads with spintronic devices for use with magnetic media, such as in magnetic media drives or hard disk drives. [Background technology]

[0002] 2. Description of Related Art The heart of a computer is the hard disk drive. Information is written to and read from the disk as it rotates past read and write heads that are placed very close to the disk's magnetic surface. Microwave Assisted Magnetic Recording (MAMR) is a type of energy-assisted recording technology that improves the recording density of magnetic recording media.

[0003] In MAMR, a spintronic device is placed near the write element to generate a high frequency alternating magnetic field. The alternating magnetic field reduces the effective coercivity of the magnetic recording medium, allowing for a lower write field from the write pole. Due to the lower write field, MAMR may enable higher recording densities in magnetic recording media. More generally, various energy-assisted recording approaches based on the spintronic effect have been explored, and there is a need in the art for improved spintronic devices for use in magnetic recording devices. Summary of the Invention

[0004] The present disclosure relates generally to magnetic recording heads with spintronic devices for magnetic media, such as in magnetic media drives.

[0005] The spintronic devices are either local or nonlocal Spin-Orbit Torque (SOT) spintronic devices.

[0006] The localized SOT spintronic device includes at least one spin Hall layer, at least one buffer layer, and at least one intermediate layer. The buffer layer is located proximate to a main pole of a write head, and the intermediate layer is located proximate to a shield of the write head. The spin Hall layer is located between the buffer layer and the intermediate layer. The spintronic device may be located at the media facing surface (MFS) or away from the MFS. The spintronic device can inject spin current into the main pole, the shield, or both.

[0007] In one embodiment, a magnetic recording head with a localized SOT spintronic device includes a main pole, a shield, and a spintronic device disposed between the main pole and the shield. The spintronic device includes a buffer layer disposed on the main pole including a material selected from Groups B, C, D, E, F, G, and H, a spin Hall layer disposed on the buffer layer including undoped BiSb or doped BiSbX (X is a dopant), and an intermediate layer disposed on the spin Hall layer including a material selected from Groups B, C, D, E, F, G, and H. Group B consists of face-centered cubic (FCC) oxide materials. Group C consists of materials that have resistivities greater than 100 μΩ·cm and can be deposited as amorphous to nanocrystalline thin films depending on deposition conditions. Group D consists of materials including Fe2VAl, Cr2CoAl, CoTiSb, Mn2VSi, V2Al, [Mn 0.5 Co 0.5 ]2VAl,[Mn 0.75 Co 0.25Group E consists of crystalline high-polarizability layers using magnetic or Heusler alloys that have large spin polarization and are difficult to mix with the spin Hall layer. Group F consists of amorphous nonmagnetic, highly resistive electrical shunt block layers that do not promote strong (012)BiSbX texture or growth. Group G consists of metallic or ceramic amorphous materials with nearest neighbor X-ray diffraction peaks in the d-spacing of 2.19A to 2.02A. Group H consists of high perpendicular magnetic anisotropy (PMA) materials that are amorphous or crystalline materials.

[0008] In another embodiment, a magnetic head with a localized SOT spintronic device includes a main pole, a shield, and a spintronic device disposed between the main pole and the shield, the spintronic device including a first buffer layer, a first spin Hall layer comprising undoped BiSb or doped BiSbX (X is a dopant) disposed on the buffer layer, a first intermediate layer disposed on the first spin Hall layer, an insulating layer disposed on the first intermediate layer, a second buffer layer disposed on the insulating layer, a second spin Hall layer comprising undoped BiSb or doped BiSbX (X is a dopant) disposed on the second buffer layer, and a second intermediate layer disposed on the second spin Hall layer.

[0009] A magnetic recording head with a nonlocal SOT spintronic device includes a main pole disposed at a medium facing surface (MFS), a shield disposed at the MFS, a spin blocking layer disposed between the shield and the main pole, at least one nonmagnetic layer disposed at the MFS between the main pole and the shield, and at least one spin-orbit torque (SOT) layer disposed over the nonmagnetic layer and recessed from the MFS by a distance of about 20 nm to about 100 nm. The at least one SOT layer includes BiSb.

[0010] In one embodiment, a magnetic recording head with a non-local SOT spintronic device includes a main pole disposed at a medium facing surface (MFS), a shield disposed at the MFS, a non-magnetic layer disposed at the MFS between the main pole and the shield, and a spin-orbit torque (SOT) layer disposed on the non-magnetic layer and recessed from the MFS by a distance of about 20 nm to about 100 nm.

[0011] In yet another embodiment, a magnetic recording head with a nonlocal SOT spintronic device includes a main pole disposed at a medium facing surface (MFS), a first nonmagnetic layer disposed at the MFS over the main pole, a spin blocking layer disposed at the first nonmagnetic layer, a second nonmagnetic layer disposed at the MFS over the spin blocking layer, a trailing shield disposed at the second nonmagnetic layer, a first spin-orbit torque (SOT) layer disposed at the first nonmagnetic layer, and a second SOT layer disposed at the second nonmagnetic layer, the first SOT layer and the second SOT layer each being recessed from the MFS by a distance between about 20 nm and about 100 nm. [Brief description of the drawings]

[0012] So that the above-mentioned features of the present disclosure may be understood in detail, a more particular description of the present disclosure briefly summarized above can be had by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings illustrate only typical embodiments of the present disclosure, and therefore should not be considered as limiting the scope of the present disclosure, since other equally effective embodiments may be recognized. [Figure 1] FIG. 1 illustrates a disk drive embodying the present disclosure. [Diagram 2] FIG. 2 is a fragmentary cross-sectional side view through the center of a read / write head facing a magnetic medium, according to one embodiment. [Figure 3A-3B] 3A and 3B are schematic cross-sectional views of write heads with localized SOT spintronic devices according to various embodiments. [Figure 4A-4D] Figure 4A is a schematic diagram of a write head with a localized SOT spintronic device according to one embodiment, Figure 4B is an exploded view of the spintronic device of the write head of Figure 4A, Figure 4C is a schematic diagram of a multi-layer buffer layer according to one embodiment, and Figure 4D is a schematic diagram of a multi-layer interlayer according to one embodiment. [Figure 5A-5D] Figure 5A is a schematic diagram of a write head with a localized SOT spintronic device according to another embodiment, Figure 5B is an exploded view of the spintronic device of the write head of Figure 5A, Figure 5C is a schematic diagram of a multi-layer buffer layer according to one embodiment, and Figure 5D is a schematic diagram of a multi-layer interlayer according to one embodiment. [Figures 6A-6D] Figure 6A is a schematic diagram of a write head with a localized SOT spintronic device according to another embodiment, Figure 6B is an exploded view of the spintronic device of the write head of Figure 6A, Figure 6C is a schematic diagram of a multi-layer interlayer according to one embodiment, and Figure 6D is a schematic diagram of a multi-layer insulating layer according to one embodiment. [Figure 7A-7D] Figure 7A is a schematic diagram of a write head with a localized SOT spintronic device according to another embodiment, Figure 7B is an exploded view of the spintronic device of the write head of Figure 7A, Figure 7C is a schematic diagram of a multi-layer buffer layer according to one embodiment, and Figure 7D is a schematic diagram of a multi-layer insulating layer according to one embodiment. [Figure 8A-8D] Figure 8A is a schematic diagram of a write head with a localized SOT spintronic device according to another embodiment, Figure 8B is an exploded view of the spintronic device of the write head of Figure 8A, Figure 8C is a schematic diagram of a multi-layer buffer layer according to one embodiment, and Figure 8D is a schematic diagram of a multi-layer interlayer according to one embodiment. [Figure 9A-9D]Figure 9A is a schematic diagram of a write head with a localized SOT spintronic device according to another embodiment, Figure 9B is an exploded view of the spintronic device of the write head of Figure 9A, Figure 9C is a schematic diagram of a multi-layer buffer layer according to one embodiment, and Figure 9D is a schematic diagram of a multi-layer interlayer according to one embodiment. [Figure 10A] FIG. 10A is a perspective view of a write head with a non-local SOT spintronic device according to one embodiment. [Figure 10B] FIG. 10B shows a portion of the write head of FIG. 10A. [Figure 11] FIG. 11 is a perspective view of a write head with a non-local SOT spintronic device according to another embodiment. [Figure 12] FIG. 12 is a perspective view of a write head with a non-local SOT spintronic device according to yet another embodiment. [Figure 13] FIG. 13 is a perspective view of a write head with a non-local SOT spintronic device according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] To facilitate understanding, the same reference numerals have been used whenever possible to designate identical elements common to the figures, and elements disclosed in one embodiment may be beneficially utilized on other embodiments without specific recitation.

[0014] Detailed explanation In the following, reference will be made to embodiments of the present disclosure. However, it should be understood that the present disclosure is not limited to the specifically described embodiments. Instead, any combination of the following features and elements, whether related to different embodiments or not, is contemplated for implementing and practicing the present disclosure. Furthermore, the embodiments of the present disclosure may achieve advantages over other possible solutions and / or over the prior art, but whether or not a particular advantage is achieved by a given embodiment does not limit the present disclosure. Thus, the following aspects, features, embodiments, and advantages are merely illustrative and are not considered elements or limitations of the appended claims unless expressly recited in the claim(s). Similarly, reference to "the present disclosure" is not to be construed as a generalization of any inventive subject matter disclosed herein, and is not to be considered elements or limitations of the appended claims unless expressly recited in the claims.

[0015] The present disclosure generally relates to a magnetic recording head including a localized SOT spintronic device for magnetic media, such as a magnetic media drive. The spintronic device includes at least one spin Hall layer, at least one buffer layer, and at least one intermediate layer. The buffer layer is disposed proximate to a main pole of the write head, and the intermediate layer is disposed proximate to a trailing shield of the write head. The spin Hall layer is disposed between the buffer layer and the intermediate layer. The spintronic device may be disposed at a medium facing surface (MFS) or may be recessed from the MFS. The spintronic device may inject spin current into the main pole, the trailing shield, or both.

[0016] FIG. 1 is a schematic diagram of a magnetic recording device 100 according to one embodiment. The magnetic recording device 100 includes a magnetic recording head, such as a write head. The magnetic recording device 100 is a magnetic media drive, such as a hard disk drive (HDD). Such a magnetic media drive may be a single drive / device or may include multiple drives / devices. For ease of illustration, a single disk drive is shown as the magnetic recording device 100 in the embodiment shown in FIG. The magnetic recording device 100 (e.g., a disk drive) includes at least one rotatable magnetic disk 112 supported on a spindle 114 and rotated by a drive motor 118. The magnetic recording on each rotatable magnetic disk 112 is in the form of any suitable pattern of data tracks, such as an annular pattern of concentric data tracks on the rotatable magnetic disk 112.

[0017] At least one slider 113 is disposed in proximity to the rotatable magnetic disk 112. Each slider 113 supports a head assembly 121. The head assembly 121 includes one or more magnetic recording heads (e.g., read / write heads), such as a write head including a spintronics device. As the rotatable magnetic disk 112 rotates, the slider 113 moves radially in and out over the disk surface 122 so that the head assembly 121 can access different tracks of the rotatable magnetic disk 112 where desired data is written. Each slider 113 is attached to an actuator arm 119 via a suspension 115. The suspension 115 provides a slight spring force that biases the slider 113 toward the disk surface 122. Each actuator arm 119 is attached to an actuator 127. The actuator 127 shown in FIG. 1 may be a voice coil motor (VCM). The VCM comprises a coil movable within a fixed magnetic field, with the direction and speed of coil movement controlled by motor current signals provided by a control unit 129 .

[0018] Head assembly 121, such as a write head of head assembly 121, includes a medium facing surface (MFS), such as an air bearing surface (ABS), that faces disk surface 122. During operation of magnetic recording device 100, rotation of rotatable magnetic disk 112 creates an air or gas bearing between slider 113 and disk surface 122 that exerts an upward force or lift on slider 113. In this manner, the air or gas bearing counters the slight spring force of suspension 115 and supports slider 113 slightly above and a small, substantially constant spacing off disk surface 122 during operation.

[0019] Each component of the magnetic recording device 100 is controlled by control signals generated by a control unit 129, such as access control signals and internal clock signals. The control unit 129 includes a logic control circuit, a storage means, and a microprocessor. The control unit 129 generates control signals for controlling 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 desired current profiles to optimally move and position the slider 113 to a desired data track on the rotatable magnetic disk 112. Write and read signals are communicated to and from the head assembly 121 by a recording channel 125. In one embodiment, which can be combined with other embodiments, the magnetic recording device 100 can further include multiple media, or disks, multiple actuators, and / or multiple sliders.

[0020] Figure 2 is a schematic diagram of a cross-sectional side view of a head assembly 200 facing the rotatable magnetic disk 112 or other magnetic storage medium shown in Figure 1, according to one embodiment. Head assembly 200 can correspond to head assembly 121 described in Figure 1. Head assembly 200 includes an MFS 212, such as an ABS, facing the rotatable magnetic disk 112. As shown in Figure 2, the rotatable magnetic disk 112 moves relatively in the direction indicated by arrow 232, and head assembly 200 moves relatively in the direction indicated by arrow 234.

[0021] In one embodiment, which can be combined with other embodiments, the head assembly 200 includes a magnetic read head 211. The magnetic read head 211 can include a sensing element 204 disposed between shields S1 and S2. The sensing element 204 is a magnetoresistive (MR) sensing element, such as a tunneling magneto-resistive (TMR) effect, a giant magneto-resistive (GMR) effect, an extraordinary magneto-resistive (EMR) effect, or a spin torque oscillator (STO) effect. The magnetic field of a magnetized region in the rotatable magnetic disk 112 can be detected by the sensing element 204 as a recording bit, such as a perpendicularly recorded bit or a longitudinally recorded bit.

[0022] The head assembly 200 includes a write head 210. In one embodiment, which may be combined with other embodiments, the write head 210 includes a main pole 220, a leading shield 206, a trailing shield (TS) 240, and a spintronic device 230 disposed between the main pole 220 and the TS 240. Each of the main pole 220, the spintronic device 230, the leading shield 206, and the TS 240 have a front portion at the MFS. It should be noted that although various embodiments are illustrated with the spintronic device 230 (in the form of a SOT-based device) disposed in the gap between the main pole 220 and the TS 240, the spintronic device 230 can be disposed between the main pole 220 and other shields (e.g., side shields or leading shields) of the main pole. Thus, references below to a trailing shield can be substituted with other shields, such as a leading shield or a side shield. Such a trailing shield implementation is provided for illustrative purposes and is not intended to limit the scope of the embodiments.

[0023] The main pole 220 includes a magnetic material such as CoFe, CoFeNi, NiFe, or FeNiRe, or other suitable magnetic material. In one embodiment, which can be combined with other embodiments, the main pole 220 includes grains of randomly textured magnetic material, such as a body-centered cubic (BCC) material formed with a random texture. In one example, the random texture of the main pole 220 is formed by plating. The write head 210 includes a coil 218 around the main pole 220 that energizes the main pole 220 to generate a write magnetic field to affect the magnetic recording medium of the rotatable magnetic disk 112. The coil 218 may be a spiral structure or one or more sets of pancake structures.

[0024] In one embodiment, which can be combined with other embodiments, the main pole 220 includes a trailing taper 242 and a leading taper 244. The trailing taper 242 extends from a location away from the MFS 212 to the MFS 212. The leading taper 244 extends from a location away from the MFS 212 to the MFS 212. The trailing taper 242 and the leading taper 244 may have the same degree of taper or different degrees of taper relative to the longitudinal axis 260 of the main pole 220. In one embodiment, which can be combined with other embodiments, the main pole 220 does not include the trailing taper 242 and the leading taper 244. In such an embodiment, the main pole 220 includes trailing and leading sites that are substantially parallel.

[0025] The TS 240 includes a magnetic material such as FeNi or other suitable magnetic material and serves as a second pole and a return pole for the main pole 220. The leading shield 206 may provide electromagnetic shielding functionality and is separated from the main pole 220 by a leading gap 254.

[0026] In some embodiments, the spintronic device 230 is a local SOT device based on SHE and is placed in close proximity to the main pole 220 to assist in writing. In such embodiments, a current is applied to the spintronic device 230 from a current source 270. A spin-orbit torque (SOT) from the spin Hall layer, also called the Spin Hall Effect (SHE) layer, provides this assistance to the main pole or trailing shield. A current in plane (CIP) in the SHE layer causes a spin current generated perpendicular to the plane to accumulate at the top and bottom surfaces of the SHE layer. A magnetic layer in contact with the SHE layer (e.g., the main pole or trailing shield) will experience a torque transverse to the CIP, which may help magnetize the write pole to improve writability. The torque transverse to the CIP assists in fast switching of the main pole, and the torque transverse to the CIP improves writability because the main pole magnetizes faster for fast switching.

[0027] In some embodiments, the spintronic device 230 is a non-local SOT device based on SHE and is placed in close proximity to the main pole 220 to assist in writing. Spin-orbit torque (SOT) from a spin Hall effect (SHE) layer or a SOT layer injects spin current into a non-magnetic layer in contact with the main pole and / or trailing shield, depending on the embodiment. The spin current magnetizes the main pole and / or trailing shield and reduces the write gap field, thus assisting in switching the magnetization of the main pole and / or trailing shield and improving writeability.

[0028] 3A and 3B are schematic cross-sectional views of a write head with a localized SOT spintronic device according to various embodiments. As shown in FIG. 3A, a current (Jc) is injected into the spin Hall layer 302 perpendicular to an axis extending between the main pole 306 and the trailing shield 308. Because the spin Hall layer 302 is in direct contact with both the main pole 306 and the trailing shield 308, a current shunt occurs in which not 100% of Jc flows inside the SHL layer 302. By inserting a highly resistive spin blocking layer (SBL) 304 shown in FIG. 3B between the trailing shield 308 and the spin Hall layer 302 and between the main pole 306 and the spin Hall layer 302, the shunt is interrupted because the resistivity of the SBL 304 is higher than that of the SHE material. The SBL 304 is a magnetic material that, in one embodiment, experiences SOT with the SHE material and / or exchange coupling with the trailing shield 308 or the main pole 306.

[0029] FIG 4A is a schematic diagram of a write head 400 with a local SOT spintronic device according to one embodiment. FIG 4B is an exploded view of the local SOT spintronic device of the write head 400 of FIG 4A. The write head 400 includes a main pole 402, a trailing shield 404, and a side shield 406. The local SOT spintronic device 408 is disposed between the main pole 402 and the trailing shield 404. The local SOT spintronic device 408 includes a buffer layer 410, a spin Hall layer 412, and an intermediate layer 414.

[0030] The local SOT spintronic device 408 is in the MFS 430, as are the trailing shield 404, the main pole 402, and the side shields 406. In particular, the buffer layer 410, the spin Hall layer 412, and the intermediate layer 414 each have a surface in the MFS. The surfaces in the MFS have a width w extending in the "X" direction and a height h extending in the "Y" direction, and each layer of the spintronic device also has a depth d extending in the "Z" direction. The depth is the dimension in the head that is perpendicular to the MFS. The height is the dimension that extends between the main pole 402 and the trailing shield 404. The width is the dimension perpendicular to the height along the MFS. As shown in Figures 4A and 4B, the buffer layer 410, the spin Hall layer 412, and the intermediate layer 414 all have the same depth and width, although the buffer layer 410, the spin Hall layer 412, and the intermediate layer 414 may have different widths and depths. Additionally, although the buffer layer 410, the spin Hall layer 412, and the intermediate layer 414 are shown as having different heights, the buffer layer 410, the spin Hall layer 412, and the intermediate layer 414 may have the same height.

[0031] In operation, a current (Jc) is injected into the spin Hall layer 412 and flows transverse to the plane, and spins are accumulated above and below the spin Hall layer from the SHE. A spin current (Js) is spontaneously generated and flows through the trailing shield 404 and main pole 402. The intermediate layer 414 and buffer layer 410 optimize the spin Hall layer for a (012) orientation while minimizing diffusion and roughness, thereby enhancing the torque exerted by the spin Hall layer on the trailing shield 404 and main pole 402 and improving writability.

[0032] A number of materials can be used for localized SOT spintronic devices using textured (100) or amorphous seed layers to grow textured spin Hall layers BiSb(012). One group of materials, group A, includes V, V3Al, Mn3Al, Nb, Mo, W, Ta, WTi 50or BCC materials used in combination with a (100) texture layer such as Cr (heated above ~250°C), RuAl, IrAl, CoAl, B2 phase, NiAl-B2 phase, CrMo(Mo~20~50at.%)-A2,B2 phase, A2CrX (X is about 10at.%, heated above ~250°C, and selected from Ru, Ti, W, and Mo).

[0033] Group A materials provide texturing to the trailing layer and are sometimes called MgO(100) textured layer stacks. Generally speaking, deposition of a boron-affinity element or alloy, such as an alloy of tantalum, tungsten, or titanium, followed by deposition of a boron-containing magnetic layer results in the formation of an amorphous magnetic layer material, such as cobalt iron boron or cobalt boron, but the boron is extracted leaving a magnetic cobalt iron or cobalt layer. On top of that layer, MgO can be formed with a (100) texture. Other methods of making MgO(100) include growing textured layers of heated chromium and ruthenium aluminum. MgO(100) textured layer stacks can also be fabricated by depositing a magnetic boron alloy of CoFeB or CoB on a thin high-B gettering alloy seed layer of Hf, Ta, W, Ti, or alloys containing these elements, followed by a thin MgO on top of the magnetic bilayer of Co or CoFe deposited on top of that.

[0034] Another group of materials, Group B, includes face-centered cubic (FCC) oxide materials such as FeO, CoO, NiO, ZrO, MgO, TiO, MgTiO, and MnO. Another group, Group C, includes ScN, TiN, NbN, ZrN, HfN, TaN, VN, CrN, ScC, TiC, NbC, ZrC, HfC, TaC, WC, VC, and W. 0.8 Zr 0.2 Group C materials include FCC nitrides and carbides such as C. Depending on the deposition conditions, group C materials can be deposited as amorphous to nanocrystalline thin films. The resistivities of group C materials are greater than 100-200 μΩ cm.

[0035] Another group, D, is composed of Fe2VAl, Cr2CoAl, CoTiSb, Mn2VSi, V2Al, [Mn 0.5 Co 0.5 ]2VAl,[Mn 0.75 Co 0.25 Group E includes crystalline high polarization layers using magnetic or Heusler alloys with large spin polarization and low intermixing with spin Hall layers, including Co2MnSb, CoFeX, NiFeX (X=Si, Al, Mn, or Ge), CoFe, NiFe, Co2MnGe, CoMnSb, NiMnSb, Co2FeGe, Co2MnSn, and Co2MnFeGe. Group F includes amorphous nonmagnetic, highly resistive electrical shunt block layers that do not promote strong (012) BiSbX texture or growth. These include SiO2, Al2O3, SiN, AlN, SiC, SiCrOx, NiX, FeX, and CoX, where X can be one or more of these elements including Fe, Co, Ni, Ta, Hf, W, Ir, Pt, Ti, Zr, N, Ru, Ge, and B.

[0036] Another group of materials, G, consists of metallic or ceramic amorphous materials with nearest neighbor X-ray diffraction peaks in the d-spacing range of 2.19 A to 2.02 A. Such materials include the non-magnetic and magnetic materials of groups A, D, or E, which are layered or alloyed with one or more of the following elements: Cu, Ag, Ge, Al, Mg, Si, Mn, Ni, Co, Mo, Zr, Y, Bi, Hf, Ta, W, Ir, Pt, Ti, or B. These effectively form a non-magnetic amorphous layer, producing an amorphous material, or starting with an amorphous material such as a-Ge, a-NiP, etc. Group G may also include a-Ge, a-NiP and amorphous / nanocrystalline alloys that promote a strong (012) BiSb texture, including one or more of the following elements: Cu, Ag, Ge, Al, Mg, Si, Mn, Ni, Co, Mo, Zr, Y, Bi, Hf, Ta, W, Ir, Pt, Ti, or B.

[0037] Yet another group of materials, group H, are high perpendicular magnetic anisotropy (PMA) materials that can be amorphous or crystalline materials. Amorphous rare earth transition metals (RE-TM) with high PMA such as TbFeCo, TbFeB, Nd, Pr, Sm(Fe,Co)B, or heavy metals such as CoZrTaB can be used. Multilayer polycrystalline stacks of Co / Pt, Co / Pd, CoFe / Pt, Co / Tb, or CoFe / Tb (" / " indicates separation of layers in the multilayer stack) or single layer PMA materials such as CoPt, CoPtCr, CoFePt, and FePt with high Ku can be used with an amorphous high spin polarization layer next to the spin Hall layer for (012) texture growth.

[0038] 4A and 4B, the buffer layer 410 may extend from the MFS into and across the pole. In one embodiment, the buffer layer 410 may be a multi-layer structure as shown in FIG. 4C, where a bottom layer 410A adjacent to the main pole 402 is composed of a material from group D, E, or H, a middle layer 410B adjacent to the bottom layer 410A is composed of a material from group B, C, F, or G, and a top layer 410C adjacent to the spin Hall layer 412 includes a material from group G.

[0039] The intermediate layer 414 may be composed of materials from groups B, C, D, E, F, G, and H. In one embodiment, the intermediate layer 414 may be a multi-layer structure as shown in FIG. 4D, where a bottom layer 414A adjacent to the spin Hall layer 412 is composed of a material from groups B, C, E, F, or G, and a top layer 414B adjacent to the trailing shield 404 includes a material from groups D, E, or H.

[0040] The spin Hall layer 412 may be composed of undoped BiSb or doped BiSbX, where the dopant is less than about 10 at.%, and X is derived from elements that do not readily react with Bi, such as B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, or Ir, or is an alloy combination with one or more of the aforementioned elements, such as CuAg, CuNi, RuGe, etc. The spin Hall layer 412 may have a (012) crystallographic orientation.

[0041] FIG. 5A is a schematic diagram of a write head 500 with a local SOT spintronic device according to another embodiment. FIG. 5B is an exploded view of a local SOT spintronic device 508 of the write head 500 of FIG. 5A. The write head 500 includes a main pole 502, a trailing shield 504, and a side shield 506. The local SOT spintronic device 508 is disposed between the main pole 502 and the trailing shield 504. The spintronic device 508 includes a first buffer layer 510, a first spin Hall layer 512, a first intermediate layer 514, an insulating layer 516, a second buffer layer 518, a second spin Hall layer 520, and a second intermediate layer 522.

[0042] The surface of the MFS has a width w extending in the "X" direction and a height h extending in the "Y" direction, and each layer of the local SOT spintronic device also has a depth d extending in the "Z" direction. The depth is the dimension within the head perpendicular to the MFS. The height is the dimension extending between the main pole 502 and the trailing shield 504. The width is the dimension perpendicular to the height along the MFS. The spintronic device 508 is in the MFS, as are the trailing shield 504, the main pole 502, and the side shields 506. In particular, the buffer layers 510, 518, the spin Hall layers 512, 520, the insulating layer 516, and the intermediate layers 514, 522 each have a surface in the MFS. The surface of the MFS has a width and a height, and each layer of the spintronic device also has a depth.

[0043] As shown in Figures 5A and 5B, the buffer layers 510, 518, the spin-hole layers 512, 520, the insulating layer 516, and the intermediate layers 514, 522 all have the same depth and width, but the buffer layers 510, 518, the spin-hole layers 512, 520, the insulating layer 516, and the intermediate layers 514, 522 may have different widths and depths.

[0044] In operation, a current (Jc) is injected into each spin Hall layer and flows transverse to the plane. Separate current sources are used to power the trailing shield 504 and the main pole 502. Spins are accumulated above and below each spin Hall layer 512, 520 from the SHE, which creates a torque on the trailing shield 504 and the main pole 502, improving writability. An insulating layer 516 is used to separate two stacks, the first stack being the first buffer layer 510, the first spin Hall layer 512, and the first intermediate layer 514, and the second stack being the second buffer layer 518, the second spin Hall layer 520, and the second intermediate layer 522.

[0045] 5A and 5B, the first buffer layer 510 may be composed of materials from groups B, C, D, E, F, G, and H. In one embodiment, the first buffer layer 510 may be a multi-layer structure as shown in FIG. 5C, where a bottom layer 510A adjacent to the main pole 502 is composed of a material from group D, E, or H, an intermediate layer 510B adjacent to the bottom layer 510A is composed of a material from group B, C, F, or G, and a top layer 510C adjacent to the first spin Hall layer 512 includes a material from group G. Overall, the spintronic device 508, particularly the bottom layer 510A, the intermediate layer 510B, and the top layer 510C, fall within the write gap.

[0046] The first interlayer 514 extends in the x- and -x-directions and is uniform to make electrical connections, while the insulating layer 516 and the buffer layer 518 also extend and are also uniform. Both the insulating layer 516 and the second buffer layer 518 are non-conductive to prevent shunting. The first interlayer 514 may be composed of a material of Groups B, C, F, or G. The first interlayer 514 should have a width substantially equal to the widths of the insulating layer 516 and the second buffer layer 518.

[0047] The first spin Hall layer 512 may be composed of undoped BiSb or doped BiSbX, where the dopant is less than about 10 at.%, and X is derived from elements that do not readily react with Bi, such as B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, or Ir, or is an alloy combination with one or more of the aforementioned elements, such as CuAg, CuNi, RuGe, etc. The first spin Hall layer 512 may have a (012) crystallographic orientation.

[0048] As described above, the insulating layer 516 can have a width substantially equal to the width of the first intermediate layer 514 and the second buffer layer 518 .

[0049] In one embodiment, the second buffer layer 518 and the insulating layer 516 are optional when the first interlayer 514 is composed of a Group B or Group C material and the first interlayer 514 is used to epitaxially grow the second spin Hall layer 520 in the (012) crystallographic orientation.

[0050] The second spin Hall layer 520 may have a width smaller than that of the first spin Hall layer 512 so that electrical connections can be made. The second spin Hall layer 520 may be composed of undoped BiSb or doped BiSbX, with less than about 10 at.% dopant and X derived from an element that does not readily react with Bi, such as B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, or Ir, or in alloy combination with one or more of the aforementioned elements, such as CuAg, CuNi, RuGe, etc. The second spin Hall layer 520 may have a (012) crystallographic orientation.

[0051] The second interlayer 522 can have a width substantially equal to the width of the leads used to power the device. The second interlayer 522 can be composed of materials from groups B, C, D, E, F, G, and H. In one embodiment, the second interlayer 522 can be a multi-layer structure as shown in FIG. 5D, where the bottom layer 522A adjacent to the second spin Hall layer 520 is composed of a material from group B, C, F, or G, and the top layer 522B adjacent to the trailing shield 504 includes a material from group D, E, or H.

[0052] FIG 6A is a schematic diagram of a write head 600 with a local SOT spintronic device according to another embodiment. FIG 6B is an exploded view of a local SOT spintronic device 608 of the write head 600 of FIG 6A. The write head 600 includes a main pole 602, a trailing shield 604, and a side shield 606. The spintronic device 608 is disposed between the main pole 602 and the trailing shield 604. The spintronic device 608 includes an insulating layer 610, a buffer layer 612, a spin Hall layer 614, and an intermediate layer 616.

[0053] The surface of the MFS has a width w extending in the "X" direction and a height h extending in the "Y" direction, and each layer of the spintronic device also has a depth d extending in the "Z" direction. The depth is the dimension within the head that is perpendicular to the MFS. The height is the dimension that extends between the main pole 602 and the trailing shield 604. The width is the dimension along the MFS that is perpendicular to the height. A local SOT spintronic device 608 is in the MFS, as are the trailing shield 604, main pole 602, and side shields 606. In particular, the buffer layer 612, spin Hall layer 614, insulating layer 610, and intermediate layer 616 each have a surface in the MFS. The surface of the MFS has a width and a height, and each layer of the spintronic device also has a depth.

[0054] As shown in Figures 6A and 6B, the buffer layer 612, the spin-hole layer 614, the insulating layer 610, and the intermediate layer 616 all have the same depth and width, but the buffer layer 612, the spin-hole layer 614, the insulating layer 610, and the intermediate layer 616 may have different widths and depths.

[0055] In operation, a current (Jc) is injected into the spin Hall layer 614 and flows transverse to the plane. An insulating layer 610 in contact with the main pole 602 below the buffer layer 612 is used to block torque from affecting the main pole 602. Spins are accumulated from the SHE on top of the spin Hall layer 614, which creates a torque only on the trailing shield 504, improving writability.

[0056] 6A and 6B, the buffer layer 612 may be composed of a material from group G. The intermediate layer 616 may be composed of a material from groups B, C, D, E, F, G, and H. In one embodiment, the intermediate layer 616 may be a multi-layer structure as shown in FIG. 6C, where a bottom layer 616A adjacent the spin Hall layer 614 is composed of a material from group B, C, E, F, or G, and a top layer 616B adjacent the trailing shield 604 includes a material from group D, E, or H.

[0057] The spin Hall layer 614 may be composed of undoped BiSb or doped BiSbX, with less than about 10 at.% dopant and X derived from an element that does not readily react with Bi, such as B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, or Ir, or in alloy combination with one or more of the aforementioned elements, such as CuAg, CuNi, RuGe, etc. The spin Hall layer 614 may have a (012) crystallographic orientation.

[0058] The insulating layer 610 may be composed of materials from groups B, C, D, E, F, G, and H. In one embodiment, the insulating layer 610 may be a multi-layer structure as shown in FIG 6D, where a bottom layer 610A adjacent the main pole 602 is composed of a material from groups D, E, or H, and a top layer 610B adjacent the buffer layer 612 includes a material from groups B, C, F, or G.

[0059] FIG. 7A is a schematic diagram of a write head 700 with a local SOT spintronic device according to another embodiment. FIG. 7B is an exploded view of a local SOT spintronic device 708 of the write head 700 of FIG. 7A. The write head 700 includes a main pole 702, a trailing shield 704, and a side shield 706. The spintronic device 708 is disposed between the main pole 702 and the trailing shield 704. The spintronic device 708 includes a buffer layer 710, a spin Hall layer 712, an intermediate layer 714, and an insulating layer 716.

[0060] The surface of the MFS has a width w extending in the "X" direction and a height h extending in the "Y" direction, and each layer of the spintronic device also has a depth d extending in the "Z" direction. The depth is the dimension within the head that is perpendicular to the MFS. The height is the dimension that extends between the main pole 702 and the trailing shield 704. The width is the dimension along the MFS that is perpendicular to the height. The spintronic device 708 is in the MFS, as are the trailing shield 704, the main pole 702, and the side shields 706. In particular, the buffer layer 710, the spin hole layer 712, the insulating layer 716, and the intermediate layer 714 each have a surface in the MFS. The surface of the MFS has a width and a height, and each layer of the spintronic device also has a depth.

[0061] As shown in Figures 7A and 7B, the buffer layer 710, the spin-hole layer 712, the insulating layer 716, and the intermediate layer 714 all have the same depth and width, but the buffer layer 710, the spin-hole layer 712, the insulating layer 716, and the intermediate layer 714 may have different widths and depths.

[0062] In operation, a current (Jc) is injected into the spin Hall layer 712 and flows transverse to the plane. An insulating layer 716 in contact with the trailing shield 704 above the intermediate layer 714 is used to block torque from affecting the trailing shield 704. Spins are accumulated from the SHE at the bottom of the spin Hall layer 712, which creates a torque only on the main pole 702, improving writability.

[0063] 7A and 7B, the buffer layer 710 may be composed of materials from groups B, C, D, E, F, G, and H. In one embodiment, the buffer layer 710 may be a multi-layer structure as shown in FIG. 7C, where a bottom layer 710A adjacent to the main pole 702 is composed of a material from group D, E, or H, a middle layer 710B adjacent to the bottom layer 710A is composed of a material from group B, C, F, or G, and a top layer 710C adjacent to the spin Hall layer 712 includes a material from group G. The bottom layer 710A, the middle layer 710B, and the top layer 710C may have heights substantially equal to the height of the spin Hall layer 712.

[0064] The spin Hall layer 712 may be composed of undoped BiSb with less than about 10 at.% dopant or doped BiSbX, where X is derived from an element that does not readily react with Bi, such as B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, or Ir, or an alloy combination with one or more of the aforementioned elements, such as CuAg, CuNi, RuGe. The spin Hall layer 712 may have a (012) crystallographic orientation.

[0065] The insulating layer 716 may be wide enough to not expose the spin Hall layer 712. The insulating layer 716 may be composed of materials from groups B, C, D, E, F, G, and H. In one embodiment, the insulating layer 716 may be a multi-layer structure as shown in FIG. 7D, where a bottom layer 716A adjacent to the middle layer 714 is composed of a material from group B, C, F, or G, and a top layer 716B adjacent to the trailing shield 704 includes a material from group D, E, or H. The bottom layer 716A and the top layer 716B have a height sufficient to not expose the spin Hall layer 712.

[0066] FIG. 8A is a schematic diagram of a write head 800 with a local SOT spintronic device according to another embodiment. FIG. 8B is an exploded view of a local SOT spintronic device 808 of the write head 800 of FIG. 8A. The write head 800 includes a main pole 802, a trailing shield 804, and a side shield 806. The spintronic device 808 is disposed between the main pole 802 and the trailing shield 804. The spintronic device 808 includes a buffer layer 810, a spin Hall layer 812, an intermediate layer 814, and an insulating layer 816.

[0067] The surface of the MFS has a width w extending in the "X" direction and a height h extending in the "Y" direction, and each layer of the spintronic device also has a depth d extending in the "Z" direction. The depth is the dimension in the head perpendicular to the MFS. The height is the dimension extending between the main pole 802 and the trailing shield 804. The width is the dimension perpendicular to the height along the MFS. The buffer layer 810, spin Hall layer 812, and intermediate layer 814 of the spintronic device 808 are recessed from the MFS. The insulating layer 816, trailing shield 804, main pole 802, and side shields 806 all have surfaces at the MFS.

[0068] As shown in Figures 8A and 8B, the buffer layer 810, the spin Hall layer 812, and the intermediate layer 814 all have the same depth and width, but the buffer layer 810, the spin Hall layer 812, and the intermediate layer 814 may have different widths and depths.

[0069] In operation, a current (Jc) is injected into the spin Hall layer 812 and flows transverse to the plane. An insulating layer 816 in front of the buffer layer 810, spin Hall layer 812, and intermediate layer 814 protects the buffer layer 810, spin Hall layer 812, and intermediate layer 814 from reliability and diffusion issues. Spins accumulate from the SHE at the top and bottom of the spin Hall layer 812, creating a torque on the main pole 802 and trailing shield 804, improving writability.

[0070] In the embodiment of Figures 8A and 8B, the buffer layer 810 can be wide enough so that the spin Hall layer 812 is not exposed. The buffer layer 810 can be composed of materials from groups B, C, D, E, F, G and H. In one embodiment, the buffer layer 810 can be a multi-layer structure as shown in Figure 8C, where a bottom layer 810A adjacent to the main pole 802 is composed of a material from group D, E or H, a middle layer 810B adjacent to the bottom layer 810A is composed of a material from group B, C, F or G, and a top layer 810C adjacent to the spin Hall layer 812 includes a material from group G. The bottom layer 810A, the middle layer 810B and the top layer 810C have a height sufficient so that the spin Hall layer 812 is not exposed.

[0071] The intermediate layer 814 may be composed of materials from groups B, C, D, E, F, G, and H. In one embodiment, the intermediate layer 814 may be a multi-layer structure as shown in FIG. 8D where a bottom layer 814A adjacent the spin Hall layer 812 is composed of a material from groups B, C, E, F, or G, and a top layer 814B adjacent the trailing shield 804 includes a material from groups D, E, or H.

[0072] The spin Hall layer 812 may be composed of undoped BiSb or doped BiSbX, where the dopant is less than about 10 at.%, and X is derived from elements that do not readily react with Bi, such as B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, or Ir, or is an alloy combination with one or more of the aforementioned elements, such as CuAg, CuNi, RuGe, etc. The spin Hall layer 812 may have a (012) crystallographic orientation.

[0073] Insulating layer 816 may be composed of Group B, C, or F materials.

[0074] FIG 9A is a schematic diagram of a write head 900 with a local SOT spintronic device according to another embodiment. FIG 9B is an exploded view of a local SOT spintronic device 908 of the write head 900 of FIG 9A. The write head 900 includes a main pole 902, a trailing shield 904, and a side shield 906. The spintronic device 908 is disposed between the main pole 902 and the trailing shield 904. The spintronic device 908 includes a buffer layer 910, a spin Hall layer 912, an intermediate layer 914, and an insulating layer 916.

[0075] The surface of the MFS has a width w extending in the "X" direction and a height h extending in the "Y" direction, and each layer of the spintronic device also has a depth d extending in the "Z" direction. The depth is the dimension within the head perpendicular to the MFS. The height is the dimension extending between the main pole 902 and the trailing shield 904. The width is the dimension perpendicular to the height along the MFS. The buffer layer 910, spin Hall layer 912, and intermediate layer 914 of the spintronic device 908 are recessed from the MFS. The insulating layer 916, trailing shield 904, main pole 902, and side shields 906 all have surfaces at the MFS.

[0076] 9A and 9B, the buffer layer 910, the spin Hall layer 912, and the intermediate layer 914 all have the same depth and width, although the buffer layer 910, the spin Hall layer 912, and the intermediate layer 914 may have different widths and depths. Additionally, the main pole 902 has an inclined surface 918 facing the buffer layer 910. Similarly, the trailing shield 904 has an inclined surface 920 facing the intermediate layer 914.

[0077] In operation, a current (Jc) is injected into the spin Hall layer 912 and flows transverse to the plane. An insulating layer 916 in front of the buffer layer 910, spin Hall layer 912, and intermediate layer 914 protects the buffer layer 910, spin Hall layer 912, and intermediate layer 914 from reliability and diffusion issues. Spins accumulate from the SHE at the top and bottom of the spin Hall layer 912, generating a torque on the main pole 902 and trailing shield 904, improving writability.

[0078] In the embodiment of Figures 9A and 9B, the buffer layer 910 may be composed of materials from groups B, C, D, E, F, G, and H. In one embodiment, the buffer layer 910 may be a multi-layer structure as shown in Figure 9C, where a bottom layer 910A adjacent to the main pole 902 is composed of a material from group D, E, or H, a middle layer 910B adjacent to the bottom layer 910A is composed of a material from group B, C, F, or G, and a top layer 910C adjacent to the spin Hall layer 912 includes a material from group G. Due to the sloping surface 918, the buffer layer 910 may be amorphous. The bottom layer 910A, the middle layer 910B, and the top layer 910C have sufficient height so that the spin Hall layer 912 is not exposed.

[0079] The middle layer 914 may be composed of materials from groups B, C, D, E, F, G, and H. In one embodiment, the middle layer 914 may be a multi-layer structure as shown in FIG. 9D, where a bottom layer 914A adjacent to the spin Hall layer 912 is composed of a material from groups B, C, F, or G, and a top layer 914B adjacent to the trailing shield 904 includes a material from groups D, E, or H. The bottom layer 914A and the top layer 914B are of sufficient height so that the spin Hall layer 912 is not exposed.

[0080] The spin Hall layer 912 may be composed of undoped BiSb or doped BiSbX, with less than about 10 at.% dopant and X derived from an element that does not readily react with Bi, such as B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, or Ir, or in alloy combination with one or more of the aforementioned elements, such as CuAg, CuNi, RuGe, etc. The spin Hall layer 912 may have a (012) crystallographic orientation.

[0081] Insulating layer 916 can be composed of Group B, C, or F materials.

[0082] By utilizing a localized SOT spintronic device having at least one spin Hall layer, at least one buffer layer, and at least one intermediate layer, the SHE can be improved to inject spin current into either the main pole or the trailing shield, or both. The spintronic device subjects the main pole and the trailing shield to a torque, which magnetizes the main pole and the trailing shield, improving the writability of the write head. The buffer layer and the intermediate layer act as interrupters of the SHE shunt between the spin Hall layer and the main pole, and between the spin Hall layer and the trailing shield.

[0083] In one embodiment, a magnetic recording head includes a main pole, a trailing shield, and a local SOT spintronic device disposed between the main pole and the trailing shield. The spintronic device includes a buffer layer disposed on the main pole and including a material selected from the group consisting of Group B, Group C, Group D, Group E, Group F, Group G, or Group H, a spin Hall layer disposed on the buffer layer and including undoped BiSb or doped BiSbX (X is a dopant), and an intermediate layer disposed on the spin Hall layer and including a material selected from the group consisting of Group B, C, D, E, F, G, and H. Group B is comprised of face-centered cubic (FCC) oxide materials. Group C is comprised of materials that have resistivities greater than 100 μΩ·cm and can be deposited as amorphous to nanocrystalline thin films depending on deposition conditions. Group D is comprised of materials such as Fe2VAl, Cr2CoAl, CoTiSb, Mn2VSi, V2Al, [Mn 0.5 Co 0.5 ]2VAl,[Mn 0.75 Co 0.25Group E consists of crystalline high spin polarization layers using magnetic or Heusler alloys that have large spin polarization and are difficult to mix with the spin Hall layer. Group F consists of amorphous nonmagnetic and highly resistive electrical shunt block layers that do not promote strong (012)BiSbX texture or growth. Group G consists of metallic or ceramic amorphous materials with nearest neighbor X-ray diffraction peaks in the d-spacing of 2.19 A to 2.02 A. Group H consists of high perpendicular magnetic anisotropy (PMA) materials that can be amorphous or crystalline materials. Group E consists of one or more of Co2MnSb, CoFeX, NiFeX (X=Si, Al, Mn, or Ge), CoFe, NiFe, Co2MnGe, CoMnSb, NiMnSb, Co2FeGe, Co2MnSn, and Co2MnFeGe. Group F consists of SiO2, Al2O3, SiN, AlN, SiC, SiCrOx, NiX, FeX, or CoX, where X is one or more of Fe, Co, Ni, Ta, Hf, W, Ir, Pt, Ti, Zr, N, Ru, Ge, and B. Group G consists of the non-magnetic and magnetic materials of Groups A, D, and E, layered or alloyed with one or more of the elements Cu, Ag, Ge, Al, Mg, Si, Mn, Ni, Co, Mo, Zr, Y, Bi, Hf, Ta, W, Ir, Pt, Ti, or B, where Group A consists of the body-centered cubic (BCC) materials: V, V3Al, Mn3Al, Nb, Mo, W, Ta, WTi 50, or BCC materials used in combination with a (100) texture layer. Group A consists of Cr, RuAl, IrAl, CoAl, NiAl, CrMo, or CrX, where X is selected from Ru, Ti, W, and Mo. Group G consists of a-Ge, a-NiP, and amorphous or nanocrystalline alloys that promote a strong (012)BiSb texture, including one or more of the following elements: Cu, Ag, Ge, Al, Mg, Si, Mn, Ni, Co, Mo, Zr, Y, Bi, Hf, Ta, W, Ir, Pt, Ti, or B. Group H consists of amorphous rare earth transition metal (RE-TM) alloys with high PMA. Group H consists of TbFeCo, TbFeB, Nd, Pr, Sm(Fe,Co)B, or CoZrTaB. Group H consists of high Ku CoPt, CoPtCr, CoFePt, and FePt single-layer PMA materials with polycrystalline stacks of Co / Pt, Co / Pd, CoFe / Pt, Co / Tb, or CoFe / Tb (" / " indicates separation of layers in the multilayer stack), or an amorphous high polarizing layer for (012) texture growth next to the spin Hall layer. Group B consists of FeO, CoO, NiO, ZrO, MgO, TiO, MgTiO, or MnO. The main pole has a first surface disposed at a medium facing surface (MFS), and the trailing shield has a second surface disposed at the MFS. The magnetic head further comprises a first insulating layer disposed between the main pole and the trailing shield and having a third surface disposed at the MFS. The spintronic device is disposed between the main pole and the trailing shield and away from the MFS. The magnetic recording apparatus also includes a magnetic head.

[0084] In another embodiment, a magnetic head includes a main pole, a trailing shield, and a local SOT spintronic device disposed between the main pole and the trailing shield. The spintronic device includes a first buffer layer, a first spin Hall layer including undoped BiSb or doped BiSbX (X is a dopant) disposed on the buffer layer, a first intermediate layer disposed on the first spin Hall layer, an insulating layer disposed on the first intermediate layer, a second buffer layer disposed on the insulating layer, a second spin Hall layer including undoped BiSb or doped BiSbX (X is a dopant) disposed on the second buffer layer, and a second intermediate layer disposed on the second spin Hall layer. The first buffer layer includes a multilayer structure. The second intermediate layer includes a multilayer structure. The spin Hall layer is recessed from the medium facing surface. The magnetic recording device includes a magnetic head.

[0085] In another embodiment, a magnetic head includes a main pole, a trailing shield, and a local SOT spintronic device disposed between the main pole and the trailing shield. The spintronic device includes a buffer layer, a spin Hall layer including undoped BiSb or doped BiSbX (X is a dopant) disposed on the buffer layer, an intermediate layer disposed on the spin Hall layer, and an insulating layer disposed between the spintronic device and the main pole or the trailing shield. The buffer layer and the intermediate layer each include multiple layers. The magnetic recording device includes the magnetic head.

[0086] 10A-13 are perspective views of write heads 1300, 1400, 1500, 1600 with non-local SOT spintronic devices according to various embodiments. FIG 10B shows a portion of the write head 1300 of FIG 10A. Each of the write heads 1300, 1400, 1500, 1600 may be the write head 210 of FIG 2 or may be part of the magnetic recording device 100 of FIG 1. Aspects of the various write heads 1300, 1400, 1500, 1600 may be used in combination with each other.

[0087] The write head 1300 with the nonlocal SOT spintronic device of FIG. 10A includes a main pole 1302 that extends to the MFS, a trailing shield 1304 that extends to the MFS, and a non-magnetic (NM) layer 1306 disposed between the main pole 1302 and the trailing shield 1304. The NM layer 1306 extends to the MFS and is disposed in the trailing gap 1311. A spin blocking layer (SBL) 1310, or spin absorbing layer, is disposed between the trailing shield 1304 and the NM layer 1306 in the trailing gap 1311. Thus, the trailing shield 1304 is spaced apart from the NM layer 1306. In some embodiments, an insulating layer (not shown) may be disposed between a portion of the trailing shield 1304 and the NM layer 1306 and / or between the main pole 1302 and the NM layer 1306. The NM layer 1306 is sometimes referred to herein as the nonmagnetic spin transport layer 1306 .

[0088] A spin-orbit torque (SOT) layer 1308, which may also be referred to as a spin Hall layer or spin Hall effect (SHE) layer, is disposed on the trailing shield facing surface 1305 of the NM layer 1306. As shown in FIG. 10B, a seed layer 1307 is disposed between the SOT layer 1308 and the NM layer 1306, and a buffer layer 1309 is disposed on the SOT layer 1308. The seed layer 1307 is disposed in contact with both the NM layer 1306 and the SOT layer 1308. The SOT layer 1308 is recessed from the MFS by a z-direction distance 1322 of about 20 nm to about 100 nm, the recessed distance in some embodiments being equal to or less than the spin diffusion length of the non-magnetic spin transport layer 1306. The SOT layer 1308 and the NM layer 1306 effectively function as a spintronics device for spin current injection / transport. 10B, the SOT layer 1308 has a length (L) 1312 in the x-direction of about 100 nm or more, a thickness (T) 1314 in the y-direction of about 10 nm, and a width 1316 in the z-direction of about 30 nm. The length 1312 of the SOT layer 1308 is significantly greater than the thickness 1314 of the SOT layer 1308. Thus, the ratio of the length 1312 to the thickness 1314 (L / T) is greater than 1, e.g., about 10 or more.

[0089] In some embodiments, the SOT layer 1308 has a BiSb(012) orientation to achieve the highest spin-Hall angle (current-spin conversion efficiency), with some suitable buffer layer below and intermediate layer above to minimize diffusion and roughness (i.e., the SOT layer 1308 is sandwiched between the buffer layer and the intermediate layer). The converted spin current 1324 flowing inside the NM layer 1306 flows toward the MFS, creating a torque on the trailing shield 1304 and main pole 1302, improving writeability as described above. The SOT layer 1308 may be composed of undoped BiSb or doped BiSbX, with less than about 10 at.% dopant and X derived from an element that does not readily react with Bi, such as B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, or Ir, or in alloy combination with one or more of the aforementioned elements, such as CuAg, CuNi, RuGe, etc.

[0090] To grow a textured SOT layer 1308 (012) using a textured (100) or amorphous seed layer, a number of materials can be utilized as the seed layer 1307 and buffer layer 1309. One group of materials, A, includes V, V3Al, Mn3Al, Nb, Mo, W, Ta, WTi 50 , body-centered cubic (BCC), such as NiAl, RhAl, or alloy combinations of these materials with similar lattice parameters, or BCC materials used in combination with a (100) textured layer, such as Cr (heated above about 250°C), RuAl, IrAl, CoAl, B2 phase, NiAl-B2 phase, CrMo (about 20-50 at.% Mo)-A2, or B2 phase, A2CrX (X is about 10 at.%, heated above about 250°C, and selected from Ru, Ti, W, Mo).

[0091] Group A materials provide texturing for the next layer and are sometimes called MgO(100) textured layer stacks. Generally speaking, depositing a boron-affinity element or alloy, such as an alloy of tantalum, tungsten, or titanium, followed by a boron-containing magnetic layer results in an amorphous magnetic layer material, such as cobalt-iron-boron or cobalt-boron, but the boron is extracted leaving a magnetic cobalt-iron or cobalt layer. On top of that layer, MgO can be formed with a (100) texture. Other methods of making MgO(100) include growing textured layers of heated chromium or ruthenium-aluminum. MgO(100) textured layer stacks can also be fabricated by depositing a magnetic boron alloy of CoFeB or CoB on a thin high-B gettering alloy seed layer of Hf, Ta, W, Ti, or alloys containing these elements, followed by a thin MgO layer on a magnetic bilayer of Co or CoFe.

[0092] Another group of materials, Group B, includes face-centered cubic (FCC) oxide materials such as FeO, CoO, NiO, ZrO, MgO, TiO, MgTiO, and MnO. Another group, Group C, includes ScN, TiN, NbN, ZrN, HfN, TaN, VN, CrN, ScC, TiC, NbC, ZrC, HfC, TaC, WC, VC, and W. 0.8 Zr 0.2 Group C materials include FCC nitrides and carbides such as C. Depending on the deposition conditions, group C materials can be deposited as amorphous to nanocrystalline thin films. The resistivity of group C materials is in the range of 100-200 μΩ cm.

[0093] Another group, D, is composed of Fe2VAl, Cr2CoAl, CoTiSb, Mn2VSi, V2Al, [Mn 0.5 Co 0.5 ]2VAl,[Mn 0.75 Co 0.25Group E includes non-magnetic Heusler materials such as Co2VSi, CoMnNbAl, CoZrFeAl, and Ti2MnAl. Another group E includes crystalline high polarization layers using magnetic or Heusler alloys with large spin polarization and low intermixing with the spin Hall layer, including Co2MnSb, CoFeX, NiFeX, (X is one or more of Si, Al, Mn, and Ge), including CoFe, NiFe, Co2MnGe, CoMnSb, NiMnSb, Co2FeGe, Co2MnSn, and Co2MnFeGe. Another group F includes amorphous non-magnetic, highly resistive electrical shunt block layers that do not promote strong (012) BiSbX texture or growth. These include SiO2, Al2O3, SiN, AlN, SiC, SiCrOx, NiX, FeX, and CoX, where X can be one or more of these elements including Fe, Co, Ni, Ta, Hf, W, Ir, Pt, Ti, Zr, N, Ru, Ge, and / or B.

[0094] Another group, G, consists of metallic or ceramic amorphous materials with nearest neighbor X-ray diffraction peaks in the d-spacing range of 2.19 Å to 2.02 Å. Such materials include non-magnetic and magnetic materials of groups A, D, or E that are layered or alloyed with one or more of the following elements: Cu, Ag, Ge, Al, Mg, Si, Mn, Ni, Co, Mo, Zr, Y, Bi, Hf, Ta, W, Ir, Pt, Ti, or B. These effectively form non-magnetic amorphous layers, producing amorphous materials or starting with amorphous materials such as a-Ge, a-NiPX alloys (X is one of Ru, Rh, Y, Zr, Mo, Hf, Ta, W, Re, Pt, or Ir). Group G can also include a-Ge, a-NiP and amorphous / nanocrystalline alloys having one or more elements of Cu, Ag, Ge, Al, Mg, Si, Mn, Ni, Co, Mo, Zr, Y, Bi, Hf, Ta, W, Ir, Pt, Ti, or B to promote a strong (012) BiSb texture.

[0095] Yet another group H is high perpendicular magnetic anisotropy (PMA) materials, which can be amorphous or crystalline materials. Amorphous rare earth transition metals (RE-TM) with high PMA such as TbFeCo, TbFeB, Nd, Pr, Sm(Fe,Co)B, or heavy metals such as CoZrTaB can be used. Multilayer polycrystalline stacks of Co / Pt, Co / Pd, CoFe / Pt, Co / Tb, or CoFe / Tb (" / " indicates layer separation), or single layer PMA materials such as CoPt, CoPtCr, CoFePt, and FePt with high Ku can be used with an amorphous high spin polarization layer next to the spin Hall layer for (012) texture growth.

[0096] The NM layer 1306 may be composed of a non-magnetic material such as Cu or Al. In one embodiment, the NM layer 1306 may be a multi-layer structure. The NM layer 1306 has a thickness in the y direction of about 10 nm. The SBL 1310 may be composed of a higher resistivity material and higher spin scattering / shorter spin diffusion length such that there is no spin polarized current toward the trailing shield 1304. For example, the SBL 1310 may be composed of Ti, Ru, combinations of Ti with Ru, Pt, or Mn, combinations of Ru with Pt or Mn, and alloys thereof, or an insulating material such as AlOx, SiN, or MgO, where x is an integer equal to or greater than 1. The SBL 1310 has a thickness in the y direction of about 2 nm to about 5 nm, a width in the z direction similar to the width of the NM layer 1306, and a length in the x direction less than about 30 nm.

[0097] In operation, a current (Jc) 1326 is injected and flows transversely to the plane in the x-direction through the SOT layer 1308. For a higher spin-Hall angle (SHA) and therefore current-to-spin-current conversion efficiency, a pure spin current (Js) 1324 is generated that flows from the SOT layer 1308 into the NM layer 1306, down toward the main pole 1302 in the -y direction, then down toward the MFS in the -z direction, and finally into the main pole 1302 near the MFS, as shown in FIG. 10A. In other words, the SOT layer 1308 injects a pure spin current 1324 into the NM layer 1306. The spin current 1324 creates a torque on the main pole 1302 when it approaches the MFS side, thus improving the writeability as described above. The tapered shape of the NM layer 1306 further concentrates the spin current 1324 in the small trailing gap 1311, further improving the fast switching of the magnetization of the main pole during the write process. The SBL 1310 prevents spin torque from acting on the trailing shield 1304 .

[0098] As shown in FIG. 10B, the NM layer 1306 is tapered in size such that the NM layer 1306 is smaller in size closer to the MFS, such as having a length 1318 of about 15 nm to about 25 nm, to better concentrate the spin current 1324 at the tip 1302a of the main pole 1302. The SOT layer 1308 is disposed on the longer portion of the NM layer 1306 away from the MFS such that the SOT layer 1308 has a length 1320 of about 20 nm to about 100 nm such that the SOT layer 1308 has more overlap with the NM layer 1306 to increase spin current generation by the spin Hall effect. In some embodiments, the length 1320 of the longer portion of the NM layer 1306 is substantially the same as the length 1312 of the SOT layer 1308. By recessing the SOT layer 1308, the write head 1300 is better protected from head-media contact and heating issues that can reduce reliability, and therefore the reliability of the write head 1300 is improved.

[0099] The write head 1400 with a nonlocal SOT spintronic device of FIG. 11 is similar to the write head 1300 of FIGS. 10A-10B, except that the SBL 1310 is disposed between the main pole 1302 and the NM layer 1306, rather than between the trailing shield 1304 and the NM layer 1306. In some embodiments, an insulating layer (not shown) may be disposed between a portion of the trailing shield 1304 and the NM layer 1306, and / or between the main pole 1302 and the NM layer 1306, as discussed above. The materials and dimensions of each layer are the same as described above in FIGS. 10A-10B. For example, the SOT layer 1308 has the same L / T ratio as the write head 1300, and is recessed the same distance 1322. The SOT layer 1308 and the NM layer 1306 function as a spintronic device in effect. Although not shown, write head 1400 includes seed layer 1307 and buffer layer 1309, each disposed in contact with SOT layer 1308, similar to that shown in FIG. 10B.

[0100] Due to the different position of the SBL 1310 from the write head 1300, during operation of the write head 1400, a current (Jc) 1326 is injected and flows transverse to the plane in the −x direction through the SOT layer 1308. A spin current (Js) 1324 flows from the SOT layer 1308 through the NM layer 1306 to the trailing shield 1304. The SOT layer 1308 injects a pure spin current 1324 into the NM layer 1306. The spin current 1324 is focused in the small trailing gap 1311, which creates a torque on the trailing shield 1304, improving the writability as described above. The SBL 1310 prevents the spin torque from acting on the main pole 1302. In this way, the write head 1300 is assisted by the switching of the trailing shield 1304.

[0101] The write head 1500 with a nonlocal SOT spintronic device of FIG. 12 is similar to the write head 1300 of FIGS. 10A-10B and the write head 1400 of FIG. 11, except that the SOT layer 1308 is disposed between the first NM layer 1306a and the second NM layer 1306b. In the write head 1500, the first NM layer 1306a is disposed on the main pole 1302, the SOT layer 1308 is disposed on the first NM layer 1306a, the second NM layer 1306b is disposed on the SOT layer 1308, and the trailing shield 1304 is disposed on the second NM layer 1306b. The SBL 1310 is disposed between the first NM layer 1306a and the second NM layer 1306b, and further between the SOT layer 1308 and the MFS. The SOT layer 1308 and the NM layers 1306a, 1306b essentially function as a spintronic device. Although not shown, the write head 1500 also includes a seed layer 1307 and a buffer layer 1309, each of which is disposed in contact with the SOT layer 1308.

[0102] In some embodiments, insulating layers (not shown) may be disposed between a portion of trailing shield 1304 and second NM layer 1306b, between main pole 1302 and first NM layer 1306a, between SBL 1310 and first NM layer 1306a, between SBL 1310 and second NM layer 1306b, and between SBL 1310 and SOT layer 1308. In this manner, SBL 1310 may be spaced apart from first NM layer 1306a, second NM layer 1306b, and SOT layer 1308.

[0103] The materials and dimensions of some layers are the same as those described above in Figures 10A-10B. For example, the SOT layer 1308 has the same L / T ratio as the write head 1300 and is set back the same distance 1322. However, the width of the SBL 1310 in the Z direction may be larger than in the write heads 1300 or 1400. For example, the SBL 1310 in the write head 1500 may be about 100 nm or more wide, extending from the MFS at about 20 nm to the SOT layer 1308 at about 40 nm. Additionally, both the first NM layer 1306a and the second NM layer 1306b, each individually, may be composed of any of the materials listed above for the NM layer 1306 of Figures 10A-11.

[0104] During operation of the write head 1500, a current (Jc) 1326 is injected and flows transversely to the plane in the x-direction through the SOT layer 1308. A first spin current (Js1) 1324a is induced and flows from the SOT layer 1308 through the first NM layer 1306a to the main pole 1302, and a second spin current (Js2) 1324b is induced and flows from the SOT layer 1308 through the second NM layer 1306b to the trailing shield 1304. The first spin current 1324a flows out through the tip 1302a of the main pole 1302. The second spin current 1324b flows out through the tip of the trailing shield 1304. The SOT layer 1308 injects a pure spin current into both the first and second NM layers 1306a, 1306b.

[0105] The first and second spin currents 1324a, 1324b are each individually focused into the small trailing gap 1311, which generates a torque on the trailing shield 1304 and on the main pole 1302, improving writeability as described above. The SBL 1310 prevents interaction between the first spin current 1324a and the second spin current 1324b. Thus, the write head 1500 supports both spin current induced switching of the main pole 1302 and spin current induced switching of the trailing shield 1304 by utilizing the first and second NM layers 1306a, 1306b and the shared SOT layer 1308 therebetween.

[0106] The write head 1600 having a nonlocal SOT spintronic device in FIG. 13 is similar to the write head 1500 in FIG. 12, except that the write head 1600 includes a first SOT layer 1308a and a second SOT layer 1308b. In the write head 1600, a first NM layer 1306a is disposed on the main pole 1302, a first SOT layer 1308a is disposed on the main pole-facing surface 1303 of the first NM layer 1306a behind the main pole 1302, an SBL 1310 is disposed between the first NM layer 1306a and the second NM layer 1306b, a trailing shield 1304 is disposed on the second NM layer 1306b, and a second SOT layer 1307b is disposed on the trailing shield-facing surface 1305 of the second NM layer 1306b behind the trailing shield 1304. Both the first SOT layer 1308a and the second SOT layer 1308b are recessed a distance 1322 from the MFS. Although not shown, a portion of the main pole 1302 may extend over and around the first SOT layer 1308a, and a portion of the trailing shield 1304 may extend over and around the second SOT layer 1308b. The SOT layers 1308a, 1308b and the NM layers 1306a, 1306b effectively function as a spintronic device.

[0107] Although not shown, the write head 1600 with the nonlocal SOT spintronic device includes a seed layer 1307 and a buffer layer 1309 disposed in contact with each SOT layer 1308a, 1308b. Thus, the write head 1600 includes two seed layers 1307 and two buffer layers 1309, with each SOT layer 1308a, 1308b sandwiched between the seed layer 1307 and the buffer layer 1309.

[0108] In some embodiments, insulating layers (not shown) may be disposed between a portion of the trailing shield 1304 and the second NM layer 1306b, between the main pole 1302 and the first NM layer 1306a, and between the SBL 1310 and the first and second NM layers 1306a, 1306b. In this manner, the SBL 1310 may be spaced apart from the first NM layer 1306a and the second NM layer 1306b. Additionally, although not shown, one or more insulating layers may be disposed between the first SOT layer 1308a and the main pole 1302, and between the second SOT layer 1308b and the trailing shield 1304.

[0109] The materials and dimensions of each layer are the same as those described above in Figures 10A-10B. For example, the SOT layer 1308 has the same L / T ratio as the write head 1300 and is recessed the same distance 1322. However, the height or width of the SBL 1310 in the Z direction may be greater than in the write heads 1300, 1400, and / or 1500. For example, the SBL 1310 in the write head 1600 may have a height extending between the first and second SOT layers 1308a, 1308b from about 20 nm to about 40 nm from the MFS. Additionally, both the first NM layer 1306a and the second NM layer 1306b, each individually, may be composed of any of the materials listed above for the NM layer 1306 in FIGS. 10A-11, and both the first SOT layer 1308a and the second SOT layer 1308a, each individually, may be composed of any of the materials listed above for the SOT layer 1308 in FIGS. 10A-11.

[0110] During operation of the write head 1600, a first current (Jc1) 1326a is injected and flows transverse to the plane in the x-direction through the first SOT layer 1308a. A first spin current (Js1) 1324a flows from the first SOT layer 1308a through the first NM layer 1306a to the main pole 1302. A second current (Jc2) 1326b is injected and flows transverse to the plane in the -x-direction through the second SOT layer 1308b. A second spin current (Js2) 1324b flows from the second SOT layer 1308b through the second NM layer 1306b to the trailing shield 1304. The first SOT layer 1308a injects a pure spin current into the first NM layer 1306a, and the second SOT layer 1308b injects a pure spin current into the second NM layer 1306b.

[0111] The first and second spin currents 1324a, 1324b are each individually focused in the small trailing gap 1311, which increases the spin current density and generates more torque on the trailing shield 1304 and on the main pole 1302, improving writeability as described above. The SBL 1310 prevents magnetic interaction between the first spin current 1324a and the second spin current 1324b. Thus, the write head 1600 is driven by both switching of the main pole 1302 and switching of the trailing shield 1304 through the use of the first and second NM layers 1306a, 1306b and the first and second SOT layers 1308a, 1308b.

[0112] Thus, by recessing the SOT layer(s) from the MFS, the SOT layer(s) can be placed over and in contact with a larger NM layer that extends to the MFS, resulting in higher spin current efficiency and more spin current, and more concentrated spin current at the MFS. This allows for faster switching of the main pole and trailing shield compared to a write head that has SOT elements only at the MFS, improving writeability. Additionally, because the SOT layer(s) are recessed from the MFS, the SOT layer(s) experience less stress and / or corrosion than SOT layer(s) placed at the MFS, resulting in improved reliability of the SOT layer(s).

[0113] In one embodiment, a magnetic recording head with a nonlocal SOT spintronic device includes a main pole disposed at a medium facing surface (MFS), a shield disposed at the MFS, a nonmagnetic layer disposed at the MFS between the main pole and the shield, and a spin-orbit torque (SOT) layer disposed on the nonmagnetic layer. The SOT layer is recessed from the MFS by a distance equal to or less than the spin diffusion length of the nonmagnetic spin transport layer 1306 (about 20 nm to about 100 nm or more).

[0114] The ratio of the length of the SOT layer to the thickness of the SOT layer is greater than 1. The non-magnetic layer is tapered, and the length of the non-magnetic layer is substantially equal to the length of the SOT layer. The SOT layer includes undoped BiSb or doped BiSbX, with less than about 10 at.% dopant, where X is a material selected from the group consisting of B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, and Ir. The magnetic recording head further includes a spin blocking layer disposed between the shield and the non-magnetic layer, and the SOT layer is disposed on the side facing surface of the non-magnetic layer. The magnetic recording head further includes a spin blocking layer disposed between the main pole and the non-magnetic layer, and the SOT layer is disposed on the main pole facing surface of the non-magnetic layer. The magnetic recording device includes a magnetic recording head. The magnetic recording device further includes a control unit configured to pass a current through the SOT layer and to pass a spin current from the SOT layer through the nonmagnetic layer to the main pole.The magnetic recording device further includes a control unit configured to pass a current through the SOT layer and to pass a spin current from the SOT layer through the nonmagnetic layer to the shield.

[0115] In another embodiment, a magnetic recording head with a nonlocal SOT spintronic device includes a main pole disposed at a medium facing surface (MFS), a first nonmagnetic layer disposed at the MFS over the main pole, a second nonmagnetic layer disposed at the MFS over the first nonmagnetic layer, a trailing shield disposed over the second nonmagnetic layer, and a spin-orbit torque (SOT) layer disposed over the first and second nonmagnetic layers. The SOT layer is recessed from the MFS by a distance of about 20 nm to about 100 nm.

[0116] The ratio of the length of the SOT layer to the thickness of the SOT layer is greater than 1, and the SOT layer comprises undoped BiSb or doped BiSbX, the dopant being less than about 10 at.%, where X is a material selected from the group consisting of B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, and Ir. The magnetic recording head further comprises a spin blocking layer disposed in the MFS between the first non-magnetic layer and the second non-magnetic layer. The spin blocking layer comprises a material selected from the group consisting of Ti, Ru, a bilayer film of Ti and Ru, Pt, or Mn, a bilayer film of Ru and Pt or Mn, and alloys thereof, AlOx, SiN, and MgO, where x is an integer equal to or greater than 1. The first and second non-magnetic layers each individually comprise Cu or Al. The magnetic recording device comprises a magnetic recording head. The magnetic recording device further includes a control unit configured to pass a current through the SOT layer, pass a first spin current from the SOT layer through the first nonmagnetic layer to the main pole, and pass a second spin current from the SOT layer through the second nonmagnetic layer to the trailing shield.

[0117] In yet another embodiment, a magnetic recording head with a nonlocal SOT spintronic device includes a main pole disposed at a medium facing surface (MFS), a first nonmagnetic layer disposed at the MFS over the main pole, a spin blocking layer disposed at the first nonmagnetic layer, a second nonmagnetic layer disposed at the MFS over the spin blocking layer, a trailing shield disposed at the second nonmagnetic layer, a first spin-orbit torque (SOT) layer disposed at the first nonmagnetic layer, and a second SOT layer disposed at the second nonmagnetic layer, wherein the first SOT layer and the second SOT layer are each individually recessed from the MFS by a distance of about 20 nm to about 100 nm.

[0118] The ratio of the length of the first SOT layer to the thickness of the first SOT layer is greater than 1, and the ratio of the length of the second SOT layer to the thickness of the second SOT layer is greater than 1, and the first SOT layer and the second SOT layer each individually include BiSb. The first non-magnetic layer and the second non-magnetic layer each individually have a tapered shape, the first SOT layer is disposed on the main pole facing surface of the first non-magnetic layer, and the second SOT layer is disposed on the trailing shield facing surface of the second non-magnetic layer. The first non-magnetic layer and the second non-magnetic layer each individually include an oxide, nitride, amorphous non-magnetic shunt block layer, or a metal having a nearest neighbor X-ray diffraction peak in the d-spacing range of 2.19 Å to 2.02 Å. The spin block layer extends between the first SOT layer and the second SOT layer. The magnetic recording device includes a magnetic recording head. The magnetic recording device further includes a control unit configured to flow a first current through the first SOT layer, to flow a first spin current from the first SOT layer through the first non-magnetic layer to the main pole, to flow a second current through the second SOT layer, and to flow a second spin current from the second SOT layer through the second non-magnetic layer to the trailing shield.

[0119] While the forgoing is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope thereof, which scope is determined by the claims which follow.

Claims

1. A main pole; Shield and a local spintronic device disposed between the main pole and the shield; the localized spintronic device comprises a buffer layer disposed on the main pole, a spin Hall layer disposed on the buffer layer, and an intermediate layer disposed on the spin Hall layer; the buffer layer comprises a material selected from the group consisting of Group B, Group C, Group D, Group E, Group F, Group G, or Group H; Group B is composed of face-centered cubic (FCC) oxide materials; Group C is made up of materials that can be formed as amorphous to nanocrystalline thin films depending on the film formation conditions and have a resistivity of more than 100 μΩ cm; Group D is Fe ２ Val, Cr ２ CoAl, CoTiSb, Mn ２ VSi, V ２ Al, [Mn ０．５ Co ０．５ ] ２ VAl, [Mn ０．７５ Co ０．２５ ] ２ VSi, CoMnNbAl, CoZrFeAl, Ti ２ It is made of non-magnetic Heusler materials including MnAl, Group E is composed of a crystalline high spin polarization layer using a magnetic alloy or Heusler alloy that has a large spin polarization and is difficult to mix with the spin Hall layer, Group F consists of amorphous non-magnetic, highly resistive electrical shunt block layers that do not promote strong (012) BiSbX texture or growth; Group G is composed of metallic or ceramic amorphous materials having nearest neighboring X-ray diffraction peaks in the d-spacing range of 2.19A to 2.02A; Group H is made up of high perpendicular magnetic anisotropy (PMA) materials, which are amorphous or crystalline materials; the spin Hall layer comprises undoped BiSb or doped BiSbX, where X is a dopant; The intermediate layer comprises a material selected from the group consisting of Groups B, C, D, E, F, G, and H; Magnetic head.

2. Group E is Co ２ MnSb, CoFeX, NiFeX (X = Si, Al, Mn, or Ge), CoFe, NiFe, Co ２ MnGe, CoMnSb, NiMnSb, Co ２ FeGe, Co ２ MnSn, and Co ２ MnFeGe, 2. The magnetic head according to claim 1.

3. Group F is SiO ２ , Al ２ O ３ , SiN, AlN, SiC, SiCrOx, NiX, FeX, or CoX, where X is one or more of Fe, Co, Ni, Ta, Hf, W, Ir, Pt, Ti, Zr, N, Ru, Ge, and B; 2. The magnetic head according to claim 1.

4. Group G is composed of non-magnetic and magnetic materials from groups A, D, or E that are laminated or alloyed with one or more of the following elements: Cu, Ag, Ge, Al, Mg, Si, Mn, Ni, Co, Mo, Zr, Y, Bi, Hf, Ta, W, Ir, Pt, Ti, or B; Group A is composed of body centered cubic (BCC) materials.

2. The magnetic head according to claim 1.

5. Group A is V, V ３ Al, Mn ３ Al, Nb, Mo, W, Ta, WTi ５０ , or BCC material used in combination with a (100) textured layer; 5. The magnetic head according to claim 4.

6. Group A is composed of Cr, RuAl, IrAl, CoAl, NiAl, CrMo, or CrX, where X is selected from Ru, Ti, W, and Mo; 5. The magnetic head according to claim 4.

7. Group G is composed of amorphous or nanocrystalline alloys that promote a strong (012) BiSb texture, including a-Ge, a-NiP, and one or more of the following elements: Cu, Ag, Ge, Al, Mg, Si, Mn, Ni, Co, Mo, Zr, Y, Bi, Hf, Ta, W, Ir, Pt, Ti, or B; 2. The magnetic head according to claim 1.

8. Group H is composed of amorphous rare earth transition metals (RE-TM) with high PMA; 2. The magnetic head according to claim 1.

9. Group H is composed of TbFeCo, TbFeB, Nd, Pr, Sm(Fe,Co)B, or CoZrTaB; 7. The magnetic head according to claim 6.

10. Group H is: polycrystalline stacks of Co / Pt, Co / Pd, CoFe / Pt, Co / Tb, or CoFe / Tb (where " / " indicates the separation of layers in a multilayer stack); or (012) Composed of single-layer PMA materials of high Ku CoPt, CoPtCr, CoFePt, and FePt with an amorphous high spin polarization layer next to the spin Hall layer for texture growth; 2. The magnetic head according to claim 1.

11. Group B is composed of FeO, CoO, NiO, ZrO, MgO, TiO, MgTiO, or MnO; 2. The magnetic head according to claim 1.

12. the main pole has a first surface disposed at a media facing surface (MFS); the shield has a second surface disposed on the MFS; the magnetic head further comprises a first insulating layer disposed between the main pole and the shield and having a third surface disposed on the MFS; the local spintronic device is disposed between the main pole and the shield and is recessed from the MFS.

2. The magnetic head according to claim 1.

13. A magnetic head comprising: Magnetic recording device.

14. A main pole; Shield and a local spintronic device disposed between the main pole and the shield; The local spintronic device comprises: A first buffer layer; a first spin Hall layer disposed on the first buffer layer, the first spin Hall layer comprising undoped BiSb or doped BiSbX, where X is a dopant; a first intermediate layer disposed on the first spinhole layer; an insulating layer disposed on the first intermediate layer; a second buffer layer disposed on the insulating layer; a second spin Hall layer disposed on the second buffer layer, the second spin Hall layer comprising undoped BiSb or doped BiSbX, where X is a dopant; a second intermediate layer disposed on the second spinhole layer; Magnetic head.

15. the first buffer layer comprises a multi-layer structure; 15. The magnetic head according to claim 14.

16. The second intermediate layer comprises a multi-layer structure.

15. The magnetic head according to claim 14.

17. A magnetic head comprising: Magnetic recording device.

18. A main pole; Shield and a local spintronic device disposed between the main pole and the shield; an insulating layer disposed between the local spintronic device and the main pole or the shield; The local spintronic device comprises: A buffer layer; a spin Hall layer disposed on the buffer layer, the spin Hall layer comprising undoped BiSb or doped BiSbX, where X is a dopant; and an intermediate layer disposed on the spinhole layer. Magnetic head.

19. The buffer layer and the intermediate layer each include a plurality of layers.

20. The magnetic head according to claim 18.

20. the spin Hall layer is recessed from the medium facing surface; 20. The magnetic head according to claim 18.

21. A magnetic head comprising: Magnetic recording device.

22. a main pole disposed on a medium facing surface (MFS); a shield disposed on the MFS; a nonlocal SOT spintronic device; The nonlocal SOT spintronic device comprises: a nonmagnetic layer disposed on the MFS between the main pole and the shield; a spin orbit torque (SOT) layer recessed from the MFS by a distance of 20 nm to 100 nm and disposed on the non-magnetic layer; Magnetic recording head.

23. a ratio of the length of the SOT layer to the thickness of the SOT layer is greater than 1; 23. The magnetic recording head of claim 22.

24. the nonmagnetic layer has a tapered shape, the length of the nonmagnetic layer is substantially equal to the length of the SOT layer; 23. The magnetic recording head of claim 22.

25. The SOT layer includes undoped BiSb.

23. The magnetic recording head of claim 22.

26. The SOT layer comprises doped BiSbX, the dopant being less than about 10 at. %, where X is a material selected from the group consisting of B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, and Ir; 23. The magnetic recording head of claim 22.

27. a spin blocking layer disposed between the shield and the nonmagnetic layer; the SOT layer is disposed on a trailing side facing surface of the nonmagnetic layer; 23. The magnetic recording head of claim 22.

28. a spin blocking layer disposed between the main pole and the nonmagnetic layer; the SOT layer is disposed on a main pole facing surface of the nonmagnetic layer; 23. The magnetic recording head of claim 22.

29. 23. A magnetic recording head comprising: Magnetic recording device.

30. a control unit configured to cause a current to flow through the SOT layer and a spin current to flow from the SOT layer through the non-magnetic layer to the main pole.

30. The magnetic recording device of claim 29.

31. a control unit configured to cause a current to flow through the SOT layer and a spin current to flow from the SOT layer through the non-magnetic layer to the shield.

30. The magnetic recording device of claim 29.

32. a main pole disposed on a medium facing surface (MFS); a nonlocal SOT spintronic device; The nonlocal SOT spintronic device comprises: a first nonmagnetic layer disposed on the MFS over the main pole; a second non-magnetic layer disposed on the MFS over the first non-magnetic layer; a shield disposed on the second nonmagnetic layer; a Spin Orbit Torque (SOT) layer disposed between the first non-magnetic layer and the second non-magnetic layer and recessed from the MFS by a distance of 20 nm to 100 nm; Magnetic recording head.

33. a ratio of the length of the SOT layer to the thickness of the SOT layer is greater than 1; The SOT layer comprises undoped BiSb or doped BiSbX, where the dopant is less than 10 at. %, and X is a material selected from the group consisting of B, N, Al, Si, Ti, V, Cr, Fe, Ni, Cu, Ge, Y, Zr, Ru, Mo, Ag, Hf, Ta, W, and Ir.

33. The magnetic recording head of claim 32.

34. a spin blocking layer disposed in the MFS between the first non-magnetic layer and the second non-magnetic layer.

33. The magnetic recording head of claim 32.

35. The spin blocking layer comprises a material selected from the group consisting of Ti, Ru, a bilayer of Ti and Ru, Pt, or Mn, a bilayer of Ru and Pt or Mn, and alloys thereof, AlOx (x is an integer of 1 or more), SiN, and MgO.

35. The magnetic recording head of claim 34.

36. the first nonmagnetic layer and the second nonmagnetic layer each individually contain Cu or Al; 33. The magnetic recording head of claim 32.

37. 33. A magnetic recording head comprising: Magnetic recording device.

38. a control unit configured to pass a current through the SOT layer, pass a first spin current from the SOT layer through the first non-magnetic layer to the main pole, and pass a second spin current from the SOT layer through the second non-magnetic layer to the shield.

38. The magnetic recording apparatus of claim 37.

39. a main pole disposed on a medium facing surface (MFS); a nonlocal SOT spintronic device; The nonlocal SOT spintronic device comprises: a first nonmagnetic layer disposed on the MFS over the main pole; a spin blocking layer disposed on the first nonmagnetic layer; a second non-magnetic layer disposed on the MFS over the spin blocking layer; a trailing shield disposed on the second nonmagnetic layer; a first spin orbit torque (SOT) layer disposed on a surface of the first nonmagnetic layer facing the main pole; a second SOT layer disposed on the second nonmagnetic layer; The first SOT layer and the second SOT layer are each individually recessed from the MFS by a distance of 20 nm to 100 nm. Magnetic recording head.

40. a ratio of a length of the first SOT layer to a thickness of the first SOT layer is greater than 1; a ratio of the length of the second SOT layer to the thickness of the second SOT layer is greater than 1; the first SOT layer and the second SOT layer each individually contain BiSb; 40. The magnetic recording head of claim 39.

41. the first nonmagnetic layer and the second nonmagnetic layer each have a tapered shape; the first SOT layer is disposed on a main pole facing surface of the first nonmagnetic layer, the second SOT layer is disposed on a trailing shield facing surface of the second nonmagnetic layer; 40. The magnetic recording head of claim 39.

42. the first nonmagnetic layer and the second nonmagnetic layer each individually comprise an oxide, a nitride, an amorphous nonmagnetic shunt block layer, or a metal having a nearest neighbor x-ray diffraction peak in a d-spacing range of 2.19 Å to 2.02 Å; 40. The magnetic recording head of claim 39.

43. the spin blocking layer extends between the first SOT layer and the second SOT layer.

40. The magnetic recording head of claim 39.

44. 40. A magnetic recording head comprising: Magnetic recording device.

45. a control unit configured to: pass a first current through the first SOT layer, pass a first spin current from the first SOT layer through the first non-magnetic layer to the main pole, pass a second current through the second SOT layer, and pass a second spin current from the second SOT layer through the second non-magnetic layer to the trailing shield.

45. The magnetic recording apparatus of claim 44.

Images