Spintronic devices with negative interfacial spin scattering
By designing the negative polarization layer and interface layer of the spintronic device, the problem of reduced write field was solved, which improved the performance and recording density of the write head under low voltage or current and enhanced the effectiveness of the write field.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- WESTERN DIGITAL TECHNOLOGIES INC
- Filing Date
- 2021-05-27
- Publication Date
- 2026-05-29
Smart Images
Figure CN116670761B_ABST
Abstract
Description
[0001] Cross-references to related applications
[0002] This application claims priority to U.S. Application No. 17 / 184,543, filed February 24, 2021, which claims the benefit of U.S. Provisional Patent Application No. 63 / 133,695, filed January 4, 2021, both of which are incorporated herein by reference. Technical Field
[0003] Various aspects of this disclosure generally relate to magnetic recording heads of spintronic devices, such as write heads of data storage devices, such as magnetic media drives. Background Technology
[0004] At the heart of a computer's operation and capabilities lies the storage and writing of data to data storage devices, such as hard disk drives (HDDs). The amount of data processed by computers is increasing rapidly. This necessitates magnetic recording media with higher recording densities to enhance the functionality and capabilities of computers.
[0005] To achieve higher recording densities (e.g., exceeding 2 Tbit / in for magnetic recording media) 2 The recording density decreases, the width and spacing of the write tracks become narrower, and therefore the corresponding magnetic recording bits encoded in each write track become narrower. One challenge in narrowing the width and spacing of the write tracks is reducing the surface area of the master poles of the write head at the medium surface (MFS). As the master poles become smaller, the write field also becomes smaller, thus limiting the effectiveness of the write head.
[0006] Heat-assisted magnetic recording (HAMR) and microwave-assisted magnetic recording (MAMR) are two types of energy-assisted recording techniques that improve the recording density of magnetic recording media, such as HDDs. In MAMR, a spin-torque oscillator (STO) device is positioned close to or near the write element to generate a high-frequency AC field, for example, in the microwave band. The high-frequency AC field reduces the effective coercivity of the magnetic recording medium used to store data and allows writing to the magnetic recording medium at a lower magnetic write field emanating from the write pole. Therefore, higher recording densities of magnetic recording media can be achieved through MAMR technology.
[0007] Energy-assisted recording write heads may require undesirable high voltages and / or undesirable high currents to produce write field enhancements. High voltages and / or high currents can affect write head lifespan and reliability by degrading write head components. Reducing voltage or current, the torque-thickness product of the energy-assisted magnetic layer, can impair writer performance, reduce area density capability (ADC), and / or limit the materials used in the write head.
[0008] Therefore, there is a need for a write head that can simply and effectively improve write head performance reliability and the high torque-thickness product of the energy-assisted magnetic layer, while also promoting lower voltage or current to facilitate efficient and effective magnetic recording and high ADC of magnetic recording. Summary of the Invention
[0009] This disclosure generally relates to a magnetic recording head for a magnetic media actuator. In one example, the magnetic recording head includes a master pole, a rear shield, and a spintronic device disposed between the master pole and the rear shield. The spintronic device includes a negative polarization layer (NPL) disposed on the master pole, the NPL comprising FeTi, FeV, FeCr, or FeN; an interface layer disposed on the NPL, the interface layer comprising V, Cr, or Ru; a spacer layer disposed on the interface layer; and a field generation layer (FGL) disposed on the spacer layer. When a current is applied to the spintronic device, the NPL and a first interface disposed between the NPL and the interface layer have negative spin polarization, while the FGL and a second interface disposed between the FGL and the spacer layer have positive spin polarization.
[0010] In one embodiment, the magnetic recording head includes a master pole, a rear shield, and a spintronic device disposed between the master pole and the rear shield. The spintronic device includes a negative polarization layer disposed on the master pole, the negative polarization layer comprising Fe and one of Ti, V, Cr, or N; an interface layer disposed on the negative polarization layer, the interface layer comprising V, Cr, or Ru; a first spacer layer disposed on the interface layer; and a field generation layer disposed on the first spacer layer.
[0011] In another embodiment, the magnetic recording head includes a master pole, a rear shield, and a spintronic device disposed between the master pole and the rear shield. The spintronic device includes a negative polarization layer disposed on the rear shield, the negative polarization layer comprising at least one of Fe and Ti, V, Cr, or N; an interface layer disposed on the negative polarization layer, the interface layer comprising Cr, V, or Ru; a first interface defining the negative polarization layer and the interface layer; a first spacer layer disposed on the interface layer; a field generation layer disposed on the first spacer layer; and a second interface defining the first spacer layer and the field generation layer. The magnetic recording head further includes a current source configured to apply current through the spintronic device.
[0012] In another embodiment, the magnetic recording head includes a master pole, a rear shield, and a spintronic device disposed between the master pole and the rear shield. The spintronic device includes a negative polarization layer disposed on the master pole, the negative polarization layer comprising at least one of Fe and Ti, V, Cr, or N; an interface layer disposed on the negative polarization layer, the interface layer comprising Cr, V, or Ru; a first interface defining the negative polarization layer and the interface layer; a first spacer layer disposed on the interface layer; a field generation layer disposed on the first spacer layer; and a second interface defining the first spacer layer and the field generation layer. The magnetic recording head further includes means for applying a current through the spintronic device, wherein when a current is applied, the negative polarization layer and the first interface have negative spin polarization, and the field generation layer and the second interface have positive spin polarization. Attached Figure Description
[0013] To gain a more detailed understanding of the features described above, the brief overview of this disclosure can be further described with reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only typical embodiments of this disclosure and should not be construed as limiting the scope of this disclosure, as this disclosure acknowledges the existence of other equally effective embodiments.
[0014] Figure 1 This is a schematic diagram of a magnetic recording device according to one embodiment.
[0015] Figure 2 To be oriented according to an implementation plan Figure 1 A schematic diagram of a cross-sectional side view of a magnetic head assembly for a disk or other magnetic storage medium, as shown in the image.
[0016] Figures 3A to 3B For the purposes of various implementation schemes Figure 2 The diagram shows the MFS for writing the header.
[0017] Figure 3C This illustrates its use, according to some embodiments, for measuring when a current is applied. Figure 3A The technique of in-plane current (CIP) giant magnetoresistive (GMR) is a means of interfacial spin polarization of the internal membrane structure of spintronic devices.
[0018] Figure 4 For the implementation of an scheme Figure 3A A schematic diagram of a cross-sectional throat view of the spintronic device of the write head shown.
[0019] Figures 5A to 5B A graph showing the in-plane current (CIP) giant magnetoresistance (GMR) as a percentage of various materials used as the interface layer, according to various embodiments, versus the thickness of the interface layer (in angstroms).
[0020] Figure 6A graph showing the CIP-GMR as a percentage of various materials used in NPL, comparing the material type and composition of NPL according to various embodiments.
[0021] Figure 7 A graph showing the thickness (in angstroms) of the interface layer as a percentage of CIP-GMR according to various embodiments.
[0022] For ease of understanding, the same element symbols have been used to denote common elements in the figures where possible. It is understood that elements disclosed in one embodiment may be advantageously used in other embodiments without specific description. Detailed Implementation
[0023] In the following text, reference is made to embodiments of this disclosure. However, it should be understood that this disclosure is not limited to the specific embodiments described. In fact, any combination of the following features and elements is contemplated for implementation and practice, regardless of whether it relates to different embodiments. Furthermore, while embodiments of this disclosure may achieve advantages over other possible solutions and / or over the prior art, whether a particular advantage is achieved by a given embodiment does not limit this disclosure. Therefore, the following aspects, features, embodiments, and advantages are illustrative only and should not be considered elements or limitations of the appended claims unless expressly stated in the claims. Similarly, reference to “this disclosure” should not be construed as a generalization of any inventive subject matter disclosed herein and should not be considered elements or limitations of the appended claims unless expressly stated in the claims.
[0024] This disclosure generally relates to a magnetic recording head for a magnetic media actuator. In one example, the magnetic recording head includes a master pole, a rear shield, and a spintronic device disposed between the master pole and the rear shield. The spintronic device includes a negative polarization layer (NPL) disposed on the master pole, the NPL comprising FeTi, FeV, FeCr, or FeN; an interface layer disposed on the NPL, the interface layer comprising V, Cr, or Ru; a spacer layer disposed on the interface layer; and a field generation layer (FGL) disposed on the spacer layer. When a current is applied to the spintronic device, the NPL and a first interface disposed between the NPL and the interface layer have negative spin polarization, while the FGL and a second interface disposed between the FGL and the spacer layer have positive spin polarization.
[0025] Figure 1 This is a schematic diagram of a magnetic recording apparatus 100 according to one embodiment. The magnetic recording apparatus 100 includes a magnetic recording head, such as a write head. The magnetic recording apparatus 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 contain multiple drives / devices. For ease of illustration, in... Figure 1The illustrated embodiment presents a single disk drive as a magnetic recording device 100. The magnetic recording device 100 (e.g., a disk drive) includes at least one rotatable disk 112 supported on a spindle 114 and rotated by a drive motor 118. Magnetic recording on each rotatable disk 112 takes the form of any suitable data track pattern, such as a circular pattern of concentric data tracks on the rotatable disk 112.
[0026] At least one slider 113 is positioned near the rotatable 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 containing spintronics. As the rotatable disk 112 rotates, the sliders 113 move radially in and out above the disk surface 122, allowing the head assembly 121 to access different tracks of the rotatable disk 112 where data needs to be written. Each slider 113 is attached to an actuator arm 119 by means of 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. Figure 1 The actuator 127 shown may be a voice coil motor (VCM). The VCM contains a coil that can move within a fixed magnetic field, and the direction and speed of the coil movement are controlled by a motor current signal supplied by the control unit 129.
[0027] The head assembly 121, such as the write head of the head assembly 121, includes a media-facing surface (MFS), such as an air bearing surface (ABS) facing the disk surface 122. During operation of the magnetic recording device 100, the rotation of the rotatable disk 112 generates an air or gas bearing between the slider 113 and the disk surface 122, which exerts an upward force or lift on the slider 113. The air or gas bearing thus counterbalances the slight spring force of the suspension 115 and supports the slider 113 at a small, generally constant distance from and slightly above the disk surface 122 during operation.
[0028] Various components of the magnetic recording apparatus 100 are controlled during operation by control signals generated by the control unit 129, such as access control signals and internal clock signals. The control unit 129 includes logic control circuitry, storage components, and a microprocessor. The control unit 129 generates control signals to control various system operations, such as drive motor control signals on line 123 and head positioning and search control signals on line 128. The control signals on line 128 provide a desired current distribution profile to optimally move and position the slider 113 onto the desired data track on the rotatable disk 112. Write and read signals are transmitted into and out of the head assembly 121 via the recording channel 125. In one embodiment that can be combined with other embodiments, the magnetic recording apparatus 100 may further include multiple media or disks, multiple actuators, and / or multiple sliders.
[0029] Figure 2 To be oriented according to an implementation plan Figure 1 This is a schematic cross-sectional side view of a head assembly 200 for a rotatable disk 112 or other magnetic storage medium, shown in the diagram. The head assembly 200 can correspond to... Figure 1 The head assembly 121 is described in the text. The head assembly 200 includes a media-facing surface (MFS) 212, such as an air bearing surface (ABS), facing the swivel disk 112. Figure 2 As shown, the rotatable disk 112 moves relative to each other in the direction indicated by arrow 232, and the head assembly 200 moves relative to each other in the direction indicated by arrow 233.
[0030] In one embodiment that can be combined with other embodiments, the head assembly 200 includes a magnetic read head 211. The magnetic read head 211 may include a sensing element 204 disposed between shields S1 and S2. The sensing element 204 is a magnetoresistive (MR) sensing element that applies tunneling magnetoresistive (TMR), gravitational magnetoresistive (GMR), abnormal magnetoresistive (EMR), or spin torque oscillator (STO) effects. The magnetic field of a magnetized region in the rotatable disk 112 (e.g., a vertical or longitudinal recording bit) can be detected by the sensing element 204 as a recorded bit.
[0031] The head assembly 200 includes a write head 210. In one embodiment, which can be combined with other embodiments, the write head 210 includes a master electrode 220, a front shield 206, a rear shield (TS) 240, and a spintronic device 230 disposed between the master electrode 220 and the TS 240. The master electrode 220 serves as a first electrode. Each of the master electrode 220, the spintronic device 230, the front shield 206, and the rear shield (TS) 240 has a front portion at the MFS.
[0032] The primary electrode 220 comprises a magnetic material, such as CoFe, CoFeNi, or FeNi, or other suitable magnetic materials. In one embodiment, which can be combined with other embodiments, the primary electrode 220 comprises small grains of a randomly textured magnetic material, such as a body-centered cubic (BCC) material. In one example, the random texture of the primary electrode 220 is formed by electrodeposition. The write head 210 includes a coil 218 surrounding the primary electrode 220, which excites the primary electrode 220 to generate a write magnetic field for influencing the magnetic recording medium of the rotatable disk 112. The coil 218 may be a helical structure or one or more sets of flat structures.
[0033] In one embodiment that can be combined with other embodiments, the main electrode 220 includes a rear cone 242 and a front cone 244. The rear cone 242 extends from a position recessed from the MFS 212 to the MFS 212. The front cone 244 extends from a position recessed from the MFS 212 to the MFS 212. The rear cone 242 and the front cone 244 may have the same or different degrees of taper relative to the longitudinal axis 260 of the main electrode 220. In one embodiment that can be combined with other embodiments, the main electrode 220 does not include the rear cone 242 and the front cone 244. In this embodiment, the main electrode 220 includes a rear side and a front side, wherein the rear side and the front side are generally parallel.
[0034] TS 240 contains a magnetic material, such as FeNi or other suitable magnetic material, that serves as the second electrode for the main electrode 220 and the return electrode. The front shield 206 provides electromagnetic shielding and is separated from the main electrode 220 by the front gap 254.
[0035] In some embodiments, the spintronic device 230 is positioned close to the master electrode 220 and reduces the coercivity of the magnetic recording medium, allowing data to be recorded using a smaller write field. In such embodiments, an electronic current is applied from a current source 270 to the spintronic device 230 to generate a microwave field. The electronic current may comprise a direct current (DC) waveform, a pulsed DC waveform, and / or a pulsed current waveform that converts to positive and negative voltages, or other suitable waveforms. In other embodiments, an electronic current is applied from a current source 270 to the spintronic device 230 to generate a high-frequency alternating current (AC) field to the medium.
[0036] In one embodiment that can be combined with other embodiments, the spintronic device 230 is electrically coupled to the main electrode 220 and the TS 240. The main electrode 220 and the TS 240 are separated in one region by an insulating layer 272. A current source 270 can provide electronic current to the spintronic device 230 through the main electrode 220 and the TS 240. For direct current or pulsed current, the current source 270 may, depending on the orientation of the spintronic device 230, allow electronic current to flow from the main electrode 220 through the spintronic device 230 to the TS 240, or allow electronic current to flow from the TS 240 through the spintronic device 230 to the main electrode 220. In one embodiment that can be combined with other embodiments, the spintronic device 230 is coupled to an electrical wire to provide electronic current in addition to that from the main electrode 220 and / or the TS 240.
[0037] Figures 3A to 3B According to various embodiments Figure 2 The diagram shows the MFS view of the write head 210. Figure 3A The write head 210 includes a spintronic device 395 positioned in the track direction between the main pole 220 and TS 240. The spintronic device 395 can be used as... Figure 2 The spintronic device 230 is shown in the image. Figure 3B The write head 210 includes a reverse-structure spintronic device 330 positioned in the track direction between the main pole 220 and TS240. The spintronic device 330 can be used as... Figure 2 The spintronic device 230 is shown in the image. According to some embodiments, the spintronic devices 330 and 395 may be referred to as spin torque oscillators.
[0038] It should be understood that the magnetic recording head discussed herein is applicable to data storage devices such as hard disk drives (HDDs) and tape drives, such as tape embedded drives (TEDs) or pluggable tape media drives. An example TED is described in a co-pending patent application assigned to the same assignee as this application, U.S. Publication No. 2020 / 0258544, entitled “Tape Embedded Drive,” filed March 31, 2019, which is incorporated herein by reference. Therefore, any references to HDDs or tape drives in the detailed description are for illustrative purposes only and are not intended to limit this disclosure unless expressly claimed. Furthermore, references to magnetic recording devices or claims relating to magnetic recording devices are intended to encompass both HDDs and tape drives unless expressly claimed.
[0039] It should also be understood that the aspects disclosed herein, such as magnetic recording heads, can be used in magnetic sensor applications outside of HDDs and magnetic tape media drives (e.g., TEDs), such as in spintronic devices other than HDDs and magnetic tape media drives. As examples, the aspects disclosed herein can be used in magnetic elements (e.g., magnetic tunnel junctions as part of memory elements) in magnetoresistive random access memory (MRAM) devices, magnetic sensors, or other spintronic devices.
[0040] exist Figure 3A In the spintronic device 395, a negative polarization layer (NPL) 302 disposed on a main electrode 220, an interface layer 304 disposed on the NPL 302, a first spacer layer 310 disposed on the interface layer 304, a field generation layer (FGL) 308 disposed on the first spacer layer 310, a second spacer layer 312 disposed on the FGL 308, and a notch 314 disposed on the second spacer layer 312. The notch 314 is configured to contact the TS 240. The TS 240 may include a hot seed layer (not shown) disposed adjacent to the second spacer layer 312. The NPL 302 may be referred to as a spin injection layer (SIL). A first interface 332 is defined between the NPL 302 and the interface layer 304, and a second interface 334 is defined between the FGL 308 and the first spacer layer 310. For example, the side of the spintronic device 395 at the MFS is ion-milled or patterned to form the spintronic device shape as shown. In some embodiments, a notch (not shown) in the main electrode 220 may be formed during the formation process of the spintronic device 395.
[0041] Current source (I) STO 270 is configured to supply current to spintronic device 395. Current flowing through spintronic device 395 from TS 240 flows through spintronic device 395 to main electrode 220. Electron flow 318 flowing through spintronic device 395 flows from main electrode 220 to TS 240. The direction of the current supplied through spintronic device 395 using current source 270 is opposite to the direction of electron flow 318 through spintronic device 395.
[0042] Figure 3B Similar to Figure 3A ;However, Figure 3B A reverse-structure spintronic device 330 is shown. Figure 3BIn the spintronic device 330, a notch 314 is disposed on the main electrode 220, a first spacer layer 312 is disposed on the notch 314, an FGL 308 is disposed on the first spacer layer 312, a second spacer layer 310 is disposed on the FGL 308, an interface layer 304 is disposed on the second spacer layer 310, an NPL 302 is disposed on the interface layer 304, and a TS 240 is disposed on the NPL 302. A first interface 332 is defined between the NPL 302 and the interface layer 304, and a second interface 334 is defined between the FGL 308 and the second spacer layer 310. For example, the side of the spintronic device 330 at the MFS is ion-milled or patterned to form the spintronic device shape shown.
[0043] A current source (ISTO) 270 is configured to supply current to the spintronic device 330. The current flowing through the spintronic device 330 flows from the main electrode 220 through the spintronic device 330 to TS 240. An electron flow 316 flowing through the spintronic device 330 flows from TS 240 to the main electrode 220. The direction of the current supplied through the spintronic device 330 using the current source 270 is opposite to the direction of the electron flow 316 through the spintronic device 330. Figure 3B The direction of the current supplied to the inverted spintronic device 330 is the same as that supplied to... Figure 3A The direction of the current in the spintronic device 395 is opposite. Similarly, Figure 3B The electron flow 316 of the inverted structure spintronic device 330 and Figure 3A The electron flow 318 of the spintronic device 395 is opposite.
[0044] In spintronic devices 330 and 395, FGL 308 oscillates, while NPL 302 does not. NPL 302 is negatively spin-polarized. FGL 308 is initially magnetized in the same direction as the magnetization 320 of the master pole 220 and TS 240, which is in the direction from the master pole 220 to TS 240 (i.e., in the x-direction) and in the same direction as the electron flow. Spin torque acts on FGL 308, causing a change in the angle of magnetization M of FGL 308, precession of magnetization M, and spin flipping of FGL 308. The precession of magnetization M of FGL 308 can generate an auxiliary magnetic field, such as an AC field, emitted into the magnetic recording medium to reduce the coercivity of the recording medium. Similarly, an auxiliary magnetic field, such as a DC field, enhances the write field written from the master pole 220 into the recording medium.
[0045] This disclosure considers: depending on the passage through the writing coil (e.g.) Figure 2The polarity of the write current of coil 218 shown in the diagram, and the magnetization of the magnetic layers (e.g., main pole 220, NPL 302, FGL 308, and TS 240) can be in the direction from main pole 220 toward TS 240, as shown in the diagram. Figure 3A As shown (i.e., in the x-direction), or in the direction from TS 240 toward the main pole 220, such as Figure 3B As shown (i.e., in the x direction).
[0046] Estimate the bias voltage (Vjump) at which spin flips occur according to formula (1):
[0047] Vjump = J c *RA (1)
[0048] Where J0 is the critical current density for STT switching relative to the gap field.
[0049] In spintronic devices 330 and 395, NPL 302 is magnetic and comprises a magnetic material, and is magnetized along the gap field direction between main pole 220 and TS 240. In one embodiment that can be combined with other embodiments, NPL 302 is magnetically spliced to main pole 220. In one embodiment that can be combined with other embodiments, NPL 302 comprises multiple electronic bands, including majority and minority spin channels. For NPL 302, the minority spin channels have a conductivity greater than that of the majority spin channels.
[0050] NPL 302 contains one or more of Fe, Cr, N, Co and / or Gd, such as FeCr or iron nitride (Fe x N x In some embodiments, NPL 302 comprises one or more of Fe and Ti, V, Cr, or N. For example, NPL 302 may comprise FeTi, FeV, FeCr, or Fe4N. In one embodiment that may be combined with other embodiments, NPL 302 comprises one or more ferromagnetic materials having negative spin accumulation. In one embodiment that may be combined with other embodiments, NPL 302 comprises two materials with anti-parallel lattice alignment, such as an alloy of Co and Gd with antiparallel alignment. Although shown as a single-layer structure, NPL 302 may be a multilayer structure. NPL 302 may have a first thickness T1 in the range of about 3 nm to about 10 nm. The first thickness T1 may be varied depending on the diffusion length of NPL 302. In one example, NPL 302 comprises a spin diffusion length of about 2 nm.
[0051] In spintronic devices 330 and 395, interface layer 304 comprises a material having a long diffusion length, for example, a diffusion length longer than that of NPL 302. Interface layer 304 comprises one of Cr, V, or Ru, or alloys thereof. For example, when NPL 302 comprises one of FeTi, FeV, or FeCr, interface layer 304 comprises one of V, Cr, or Ru. When NPL 302 comprises Fe4N, interface layer 304 comprises Ru. Although shown as a single-layer structure, interface layer 304 may be a multilayer structure.
[0052] In some embodiments, interface layer 304 comprises a material having a negative interface polarization factor (γ), for example, about -0.2. The negative interface polarization factor (γ) is located at the interface between interface layer 304 and NPL 302. Interface layer 304 comprises a second thickness T2 in the range of about 0.2 nm to about 1.5 nm, for example, about 1.0 nm. Spacer layers 310, 312 comprise Cu, NiAl, or Ag-based materials. Figures 3A to 3B Each spacer layer 310 has a third thickness T3 in the range of about 1.5 nm to about 8 nm, for example, in the range of about 1.5 nm to about 2.5 nm, such as about 2.0 nm. FGL 308 comprises CoFe, NiFe, or a CoFe-based material. FGL 308 may have a thickness between about 5 nm and about 20 nm, such as about 10 nm.
[0053] Figure 3C The following is illustrated according to some embodiments for use in measuring when a current of 370 is applied. Figure 3A The spintronic device 395 utilizes in-plane current (CIP) giant magnetoresistive (GMR) technology to achieve interfacial spin polarization of the internal structure of its spintronic membrane. For clarity, Figure 3C Some layers of the spintronic device 395 have been removed. For example... Figure 3C As shown, an in-plane current 370 is applied, causing electrons (e) to flow through the interface layer 304 and the spacer layer 310. Furthermore, when current 370 is applied, NPL 302 becomes negatively spin-polarized, the first interface 332 between NPL 302 and interface layer 304 becomes negatively spin-polarized (i.e., the first interface is negatively scattering), the second interface 334 between spacer layer 310 and FGL 308 becomes positively spin-polarized, and FGL 308 becomes positively spin-polarized. Although... Figure 3C Show Figure 3A The spintronic device 395, but Figure 3B The first interface 332 and the second interface 334 of the spintronic device 330 are polarized in the same manner.
[0054] The negative spin polarization of the first interface 332 between the inverted spintronic device 330 and the spintronic device 395 is achieved through the materials of NPL 302 and interface layer 304. As discussed above, when NPL 302 comprises one of FeTi, FeV, or FeCr, interface layer 304 comprises one of V, Cr, or Ru, thereby causing the first interface 332 to be negatively spin polarized. When NPL 302 comprises Fe4N, interface layer 304 comprises Ru, thereby causing the first interface 332 to be negatively spin polarized. By selectively choosing which materials to use for NPL 302 and interface layer 304, the spin polarization of NPL 302 and the first interface 332 can be independently controlled and maximized.
[0055] Figure 4 According to one implementation scheme, it includes placement at MFS 401. Figure 3A A schematic diagram of a cross-sectional throat view of the write head 210 of the spintronic device 395. Although Figure 4 The exhibition includes Figure 3A The write head 210 of the spintronics device 395, but Figure 3B The inverted spintronic device 330 can be utilized in a similar manner. Figures 3A to 3B In the diagram, track directions are labeled as x-coordinates and crossing track directions as y-coordinates. The direction perpendicular to the MFS will be the z-coordinate for entering / leaving the XY plane. Figure 4 In this configuration, the track direction is marked as the x-coordinate, and the general magnetic stripe height direction is marked as the z-coordinate. Furthermore, one or more layers of the spintronic device 395, such as the second spacer layer 312, are... Figure 4 It may not be shown in the image.
[0056] Each layer of the spintronic device 395, the main pole 220, and the TS 240 may have the same cross track width (e.g., Figure 3A (as shown) or may have different cross track widths. NPL 302, at least one of spacer layers 310, 312, and FGL 308 may have different strip heights (e.g., as shown) Figure 4 (as shown in the diagram), or may have the same magnetic strip height. Furthermore, NPL302, at least one of spacer layers 310, 312, and FGL 308 may be tapered (as shown in the diagram). Figure 4 (as shown) or non-conical. Figure 4 The FGL 308 is positioned to contact the thermal seed layer 380 of the TS 240.
[0057] Figures 3A to 3BThe FGL 308 of the spintronic devices 330 and 395 of the 4 may comprise one or more of the following: NiFe, CoFe, CoFeNi, CoMnGe, NiCo, NiFeCu, CoFeMnGe, CoMnSi, CoFeSi and / or other soft or hard ferromagnetic materials, other Heusler alloys, other suitable magnetic layers, and / or multiple layers thereof. The FGL 308 may comprise a material having magnetic anisotropy oriented in any generally directional direction, such as perpendicular, angular, or longitudinal, to the plane of the MFS. In one embodiment that may be combined with other embodiments, the FGL 308 comprises magnetic anisotropy, such as... Figure 3A As shown in the image.
[0058] Figures 3A to 3B The first spacer layer 310 and the second spacer layer 312 of the spintronic devices 395 and 330 each comprise one or more non-magnetic conductive materials, such as Au, Ag, Al, Cu, AgSn, NiAl and / or other non-magnetic conductive materials, alloys thereof and / or multiple layers thereof. Individually, the spacer layers 310 and 312 may be made of a material having high spin transmittance for spin torque transmission on FGL 308.
[0059] Figures 3A to 3B The master pole 220 of the write head 210 shown in Figure 4 can be any suitable shape (e.g., trapezoid, triangle, etc.) with appropriate dimensions. Figures 3A to 3B The write head 210 of 4 may include a front shield located on one or more sides of the main pole 220 having a front gap therebetween. Figures 3A to 3B The write head 210 of 4 may include a side gap positioned on the side of the spintronic devices 330, 395. The side gap may contain insulating material.
[0060] NPL 302 and interface layer 304 together facilitate the operation of FGL 308. As an example, the negative spin accumulation of NPL 302 promotes the generation of direct torque on FGL 308 to facilitate the precession of magnetization of FGL 308 and / or promote spin flipping of FGL 308 against the field direction. NPL 302 facilitates the application of torque to FGL 308 from both sides, for example, in the direction from TS 240 to FGL 308 (i.e., the x-direction) and in the direction from the main pole 220 to FGL 308 (i.e., the x-direction). As an example, the negative interface polarization factor (γ) of interface layer 304 enhances the negative spin polarization of NPL 302.
[0061] These aspects facilitate lower voltages or lower currents (applied from the current source (ISTO)) for the spintronic device 395 or the inverted-structure spintronic device 330 to enhance the reliability and efficiency of the write head 210, while also promoting a high torque-thickness product and high ADC for magnetic recording of the write head 210. These aspects also facilitate various configurations of the write head 210 and modularity of materials that can be used for various components of the write head 210, which can further reduce the current density and / or voltage of the write head 210.
[0062] The NPL 302 and the interface layer 304 work together to reduce the critical current for flipping or switching FGL 308 by up to 30% relative to the seed layer on the main electrode 220, for example, by up to 15% to 20% reduction in the critical current density Jc, due to the increase in the spin-transfer torque of FGL 308.
[0063] Figures 5A to 5B Graphs 500 and 550 show the in-plane current (CIP) giant magnetoresistance (GMR) versus the thickness (in angstroms) of the interface layer as a percentage of various materials used as the interface layer according to various embodiments. (See also...) Figures 5A to 5B As mentioned in the description, the interface layer can be Figures 3A to 3C The interface layer is 304, and NPL can be NPL302. Figure 5A In the middle, FeCr 28 Used as NPL 302. Figure 5B In the middle, FeV 20 Used as NPL 302. Figures 5A to 5B In the figure, negative percentage CIP-GMR indicates the interface between NPL 302 and interface layer 304 when current is applied, for example... Figure 3C The first interface is 332 negative spin polarization (i.e., the first interface is 332 negative scattering).
[0064] like Figure 5A As shown, when interface layer 304 comprises Ru, the first interface 332 is negatively spin-polarized at a thickness between about 2 angstroms and about 15 angstroms when a current is applied. When interface layer 304 comprises V, the first interface 332 is negatively spin-polarized at a thickness between about 3 angstroms and about 15 angstroms when a current is applied. When interface layer 304 comprises Cr, the first interface 332 is negatively spin-polarized at a thickness between about 6 angstroms and about 25 angstroms when a current is applied.
[0065] Similarly, such as Figure 5BAs shown, when interface layer 304 comprises Ru, the first interface 332 is negatively spin-polarized at a thickness between about 1.5 angstroms and about 15 angstroms when a current is applied. When interface layer 304 comprises V, the first interface 332 is negatively spin-polarized at a thickness between about 1 angstrom and about 20 angstroms when a current is applied. When interface layer 304 comprises Cr, the first interface 332 is negatively spin-polarized at a thickness between about 2 angstroms and about 15 angstroms when a current is applied.
[0066] Figure 6 To illustrate the CIP-GMR curves comparing the material type and composition of NPLs as percentages of various materials used as NPLs according to various embodiments, graph 600 is provided. Figure 6 As mentioned in the description, the interface layer can be Figures 3A to 3C The interface layer 304 and NPL can be NPL 302. In graph 600, the negative percentage CIP-GMR indicates the interface between NPL 302 and interface layer 304 when current is applied, for example... Figure 3C The first interface is 332 negative spin polarization (i.e., the first interface is 332 negative scattering).
[0067] In the example shown in graph 600, interface layer 304 comprises Cr and has a thickness between about 5 angstroms and about 10 angstroms. A material comprising FeX is used as NPL 302, where X is one of Ti, V, or Cr, as shown on the x-axis. When NPL 302 comprises FeCr... 12 FeCr 16 FeCr 20 FeCr 28 FeCr 39 FeCr 46 FeCr 58 FeTi5, FeTi 11 ,FeTi 23 FeV 10 FeV 20 or FeV 30 When one of them is present, the first interface 332 becomes negatively spin polarized when a current is applied. When NPL 302 includes, for example, FeCr 71 or FeCr 83 When the material is nonmagnetic, the first interface 332 is not polarized. Therefore, when the interface layer 304 includes Cr and has a thickness between about 5 angstroms and about 10 angstroms, and NPL 302 includes FeCr... 12 FeCr 16 FeCr20, FeCr 28 FeCr 39 FeCr 46 FeCr 58FeTi5, FeTi 11 ,FeTi 23 FeV 10 FeV 20 or FeV 30 When one of them is present, the first interface 332 negatively scatters when a current is applied.
[0068] Figure 7 A graph 700 is provided to illustrate the CIP-GMR versus the thickness of the interface layer (in angstroms) as a percentage according to various embodiments. (See also...) Figure 7 As mentioned in the description, the interface layer can be Figures 3A to 3C The interface layer 304 and NPL can be NPL 302. In graph 700, the negative percentage CIP-GMR indicates the interface between NPL 302 and interface layer 304 when current is applied, for example... Figure 3C The first interface 332 is negatively spin polarized (i.e., the first interface 332 is negatively scattering). In graph 700, Fe4N is used as the material for NPL 302 and Ru is used as the material for interface layer 304. When the interface layer 304 including Ru has a thickness of about 2 angstroms to about 10 angstroms, the first interface 332 is negatively spin polarized when a current is applied.
[0069] The benefits of this disclosure include simple and effective improvement in magnetic recording performance and reliability; increased ADC for magnetic recording; reduced voltage or current while maintaining or promoting increased torque-thickness product, magnetic recording head performance and reliability; modularity in magnetic recording head materials; and modularity in the design and configuration of magnetic recording devices. Furthermore, by selectively choosing which materials to use for the NPL and interface layer, the spin polarization of the NPL and the interface disposed between the NPL and the interface layer can be independently controlled and maximized.
[0070] It is considered that one or more aspects disclosed herein may be combined. Furthermore, it is considered that one or more aspects disclosed herein may include some or all of the foregoing benefits.
[0071] In one embodiment, the magnetic recording head includes a master pole, a rear shield, and a spintronic device disposed between the master pole and the rear shield. The spintronic device includes a negative polarization layer disposed on the master pole, the negative polarization layer comprising Fe and one of Ti, V, Cr, or N; an interface layer disposed on the negative polarization layer, the interface layer comprising V, Cr, or Ru; a first spacer layer disposed on the interface layer; and a field generation layer disposed on the first spacer layer.
[0072] The magnetic recording head further includes a second spacer layer disposed on the field generation layer. The negative polarization layer comprises FeCr 12 FeCr16, FeCr20, FeCr28 FeCr 39 FeCr 46 or FeCr 58 The negative polarization layer includes FeTi5 and FeTi 11 or FeTi 23 The negative polarization layer includes FeV. 10 FeV 20 or FeV 30 The negative polarization layer comprises Fe4N and the interface layer comprises Ru. The negative polarization layer has a first thickness between about 3 nm and about 10 nm. The interface layer has a second thickness between about 0.2 nm and about 1.5 nm. The magnetic recording head further includes a current source configured to apply current through the spintronic device. When current is applied, the negative polarization layer and the first interface disposed between the negative polarization layer and the interface layer have negative spin polarization. When current is applied, the field generation layer and the second interface disposed between the field generation layer and the first spacer layer have positive spin polarization.
[0073] In another embodiment, the magnetic recording head includes a master pole, a rear shield, and a spintronic device disposed between the master pole and the rear shield. The spintronic device includes a negative polarization layer disposed on the rear shield, the negative polarization layer comprising one of Fe and Ti, V, Cr, or N; an interface layer disposed on the negative polarization layer, the interface layer comprising Cr, V, or Ru; a first interface defining the negative polarization layer and the interface layer; a first spacer layer disposed on the interface layer; a field generation layer disposed on the first spacer layer; and a second interface defining the first spacer layer and the field generation layer. The magnetic recording head further includes a current source configured to apply current through the spintronic device.
[0074] The magnetic recording head further includes a second spacer layer disposed on the field generation layer and a notch disposed between the second spacer layer and the main electrode. When a current is applied, the negative polarization layer and the first interface have negative spin polarization, and wherein the field generation layer and the second interface have positive spin polarization when a current is applied. The interface layer includes Ru, and the negative polarization layer includes Fe and one of Ti, V, Cr, or N. Alternatively, the interface layer may include Cr or V, and the negative polarization layer may include Fe and one of Ti, V, or Cr.
[0075] In another embodiment, the magnetic recording head includes a master pole, a rear shield, and a spintronic device disposed between the master pole and the rear shield. The spintronic device includes a negative polarization layer disposed on the master pole, the negative polarization layer comprising one of Fe and Ti, V, Cr, or N; an interface layer disposed on the negative polarization layer, the interface layer comprising Cr, V, or Ru; a first interface defining the negative polarization layer and the interface layer; a first spacer layer disposed on the interface layer; a field generation layer disposed on the first spacer layer; and a second interface defining the first spacer layer and the field generation layer. The magnetic recording head further includes means for applying a current through the spintronic device, wherein when a current is applied, the negative polarization layer and the first interface have negative spin polarization, and the field generation layer and the second interface have positive spin polarization.
[0076] The interface layer includes Ru, and the negative polarization layer includes materials selected from the group consisting of FeCr. 12 FeCr16, FeCr 20 FeCr 28 FeCr 39 FeCr 46 FeCr 58 FeTi5, FeTi 11 ,FeTi 23 FeV 10 FeV 20 FeV 30 And Fe4N.
[0077] While the foregoing description is directed to embodiments of this disclosure, other and additional embodiments of this disclosure may be devised without departing from the basic scope of this disclosure, the scope of which is defined by the appended claims.
Claims
1. A magnetic recording head, comprising: Main pole; Rear shielding; as well as A spintronic device, disposed between the main electrode and the rear shield, the spintronic device comprising: A negative polarization layer disposed on the main electrode, the negative polarization layer comprising Fe and one of Ti, V, Cr or N; An interface layer disposed on the negative polarization layer, the interface layer comprising V, Cr or Ru, wherein the negative interface polarization factor is located at a first interface between the interface layer and the negative polarization layer; A first spacer layer disposed on and in contact with the interface layer; and A field generation layer disposed on the first spacer layer.
2. The magnetic recording head according to claim 1, further comprising a second spacer layer disposed on the field generation layer.
3. The magnetic recording head according to claim 1, wherein the negative polarization layer comprises FeCr 12 FeCr 16 FeCr 20 FeCr 28 FeCr 39 FeCr 46 or FeCr 58 .
4. The magnetic recording head according to claim 1, wherein the negative polarization layer comprises FeV 10 FeV 20 or FeV 30 .
5. The magnetic recording head of claim 1, wherein the negative polarization layer has a first thickness between about 3 nm and about 10 nm, and wherein the interface layer has a second thickness between about 0.2 nm and about 1.5 nm.
6. The magnetic recording head of claim 1, further comprising a current source configured to apply current through the spintronic device.
7. The magnetic recording head of claim 6, wherein the negative polarization layer and the first interface have negative spin polarization when an electric current is applied.
8. The magnetic recording head of claim 6, wherein when an electric current is applied, the field generating layer and the second interface disposed between the field generating layer and the first spacer layer have positive spin polarization.
9. A magnetic recording device comprising the magnetic recording head according to claim 1.
10. A magnetic recording head, comprising: Main pole; Rear shielding; as well as A spintronic device, disposed between the main electrode and the rear shield, the spintronic device comprising: A negative polarization layer disposed on the main electrode, the negative polarization layer comprising Fe and one of Ti, V, Cr or N; An interface layer disposed on the negative polarization layer, the interface layer comprising Cr, V or Ru, wherein the negative interface polarization factor is located at a first interface between the interface layer and the negative polarization layer; A first spacer layer disposed on the interface layer; and A field generation layer disposed on the first spacer layer, wherein the negative polarization layer comprises FeTi5 and FeTi 11 or FeTi 23 .
11. A magnetic recording head, comprising: Main pole; Rear shielding; as well as A spintronic device, disposed between the main electrode and the rear shield, the spintronic device comprising: A negative polarization layer disposed on the main electrode, the negative polarization layer comprising Fe and one of Ti, V, Cr or N; An interface layer disposed on the negative polarization layer, the interface layer comprising V, Cr or Ru, wherein the negative interface polarization factor is located at a first interface between the interface layer and the negative polarization layer; A first spacer layer disposed on the interface layer; and A field generation layer disposed on the first spacer layer, wherein the negative polarization layer comprises Fe4N and the interface layer comprises Ru.
12. A magnetic recording head, comprising: Main pole; Rear shielding; as well as A spintronic device, disposed between the main electrode and the rear shield, the spintronic device comprising: A negative polarization layer disposed on the rear shield, the negative polarization layer comprising Fe and one of Ti, V, Cr or N; An interface layer disposed on the negative polarization layer, the interface layer comprising Cr, V or Ru; A first interface is defined between the negative polarization layer and the interface layer, wherein the negative interface polarization factor is located at the first interface; A first spacer layer disposed on the interface layer; A field generation layer disposed on the first spacer layer; A second spacer layer disposed on the field generation layer; A notch positioned between the second spacer layer and the main electrode; and The second interface defined between the first spacer layer and the field generation layer; and A current source is configured to apply current through the spintronic device.
13. The magnetic recording head of claim 12, wherein the negative polarization layer and the first interface have negative spin polarization when a current is applied, and wherein the field generation layer and the second interface have positive spin polarization when a current is applied.
14. The magnetic recording head of claim 12, wherein the interface layer comprises Ru and the negative polarization layer comprises Fe and one of Ti, V, Cr or N.
15. The magnetic recording head of claim 12, wherein the interface layer comprises Cr or V and the negative polarization layer comprises Fe and one of Ti, V or Cr.
16. A magnetic recording apparatus comprising the magnetic recording head according to claim 12.
17. A magnetic recording head, comprising: Main pole; Rear shielding; A spintronic device, disposed between the main electrode and the rear shield, the spintronic device comprising: A negative polarization layer disposed on the main electrode, the negative polarization layer comprising Fe and one of Ti, V, Cr or N; An interface layer disposed on the negative polarization layer, the interface layer comprising V, Cr or Ru; A first interface is defined between the negative polarization layer and the interface layer, wherein the negative interface polarization factor is located at the first interface; A first spacer layer disposed on and in contact with the interface layer; A field generation layer disposed on the first spacer layer; and The second interface defined between the first spacer layer and the field generation layer; and A component for applying current through the spintronic device, wherein when current is applied, the negative polarization layer and the first interface have negative spin polarization and the field generation layer and the second interface have positive spin polarization.
18. The magnetic recording head of claim 17, wherein the interface layer comprises Ru and the negative polarization layer comprises a material selected from the group consisting of: FeCr 12 FeCr 16 FeCr 20 FeCr 28 FeCr 39 FeCr 46 FeCr 58 FeTi5, FeTi 11 ,FeTi 23 FeV 10 FeV 20 FeV 30 And Fe4N.
19. The magnetic recording head of claim 17, wherein the field generation layer is disposed on and in contact with the first spacer layer.
20. A magnetic recording device comprising the magnetic recording head according to claim 17.