Hard magnetic write head, device and data system, method of manufacturing a write head

Abstract

The application discloses a hard magnetic write head, a device and a data system, and a write head manufacturing method. The hard magnetic write head comprises: a write-in of a Z-axis magnetoresistance sensing unit array pinning layer magnetic moment corresponding to a Z bridge arm for a Z-axis magnetoresistance sensor, the Z bridge arm comprising a +Z bridge arm and / or a -Z bridge arm, and the hard magnetic write head and a first soft magnetic shielding layer being respectively located above and below a wafer of the Z-axis magnetoresistance sensor. The hard magnetic write head comprises: a substrate and a hard magnetic pole array arranged on the substrate, a magnetic moment direction of any hard magnetic pole being a +Z or -Z direction, and a write-in end facing one Z bridge arm. When writing, the hard magnetic pole write-in end generates a direct-current write-in magnetic field containing a Z-direction component in the pinning layer of the Z bridge arm, so that the pinning layer magnetic moment turns to the direction of the Z-direction component direct-current write-in magnetic field. The application has the advantages of simple structure, high write-in efficiency and low price.

Description

Technical Field

[0001] This invention relates to the field of magnetic sensor technology, and in particular to a hard magnetic write head, device and data system, and a method for manufacturing the write head. Background Technology

[0002] MTJ magnetoresistive sensors typically employ a push-pull structure, comprising two push-and-pull magnetoresistive sensing element arrays with opposite magnetic sensitivity directions, and a pull-and-pull magnetoresistive sensing element array packaged within a single chip. For X-axis or Y-axis magnetoresistive sensors, the magnetic field sensitivity direction of the magnetotunnel is determined using an antiferromagnetic layer magnetic field annealing method. This involves placing the entire wafer in a magnetic field annealing furnace, ensuring all magnetoresistive sensing elements on the wafer share the same +X magnetic field sensitivity direction. The wafer is then sliced ​​into dies, and the +X dies are flip-dieed (rotated by 90° to obtain the +Y bridge arm, 180° to obtain the -X bridge arm, and 270° to obtain the -Y bridge arm), resulting in X-axis and Y-axis push-pull magnetoresistive sensors, respectively. The biggest problem with this method is that the rotation introduces errors in the relative positions of the dies, affecting the sensor's accuracy.

[0003] To address this issue, a laser annealing method was proposed. This method uses a laser spot to heat a single magnetoresistive sensor unit and applies magnetic fields of +X, -X, +Y, -Y, +Z, -Z. This allows for the generation of X, Y, and Z axis magnetoresistive sensors on a single die, eliminating errors caused by sensor alignment.

[0004] However, when the laser spot heats the magnetoresistive sensing unit, there is a need to adjust the laser power to ensure that the heating temperature is not too high and will cause ablation of the magnetic tunnel junction. On the one hand, the magnetic field generating device acts on the entire wafer area, which requires the device to generate the magnetic field to have an excessive current, requiring a cooling device, resulting in high production costs. On the other hand, the laser spot needs to scan all the magnetic tunnel junction units on the wafer one by one, which takes too long.

[0005] Z-axis magnetoresistive sensors are typically implemented using an X-axis magnetoresistive sensing unit and a flux concentrator. The flux concentrator alters the magnetic circuit, causing the Z-axis magnetic field to generate an X-component magnetic field near the X-axis magnetoresistive sensor. However, because the flux concentrator is made of soft magnetic material and fabricated using electroplating, it inherently exhibits hysteresis, and its thickness distribution is uneven. Therefore, this affects the repeatability and performance error of the Z-axis sensor.

[0006] On the other hand, by utilizing the vertical anisotropy (PMA) at the interface of magnetic transition metals / oxides, such as CoFeB / MgO, a vertical anisotropy tunnel junction stack structure with a dual interface of magnetic metal / oxide / magnetic metal can be formed. Vertical anisotropy magnetic material layers are formed on both sides of the oxide. By controlling the oxide, magnetic metal and thickness, with one side as a reference layer and the other as a free layer, a Z-axis magnetoresistive sensor can be formed.

[0007] Similarly, to form a push-pull Z-axis magnetoresistive sensor, it is necessary to form a magnetic tunnel junction array with +Z and -Z axes in the reference layer in order to obtain a magnetic tunnel junction array with +Z and -Z axes on a single die.

[0008] A simple, fast, and efficient Z-axis magnetoresistive sensor reference layer magnetic moment writing unit is needed to improve the writing efficiency of the Z-axis magnetoresistive sensor on the wafer. Summary of the Invention

[0009] In view of this, the present invention proposes a hard magnetic write head, device and data system, and a method for manufacturing the write head, which can improve the writing efficiency of magnetoresistive sensors.

[0010] In a first aspect, embodiments of this application provide a hard magnetic write head for writing the magnetic moment of the pinned layer of a Z-axis magnetoresistive sensing unit array corresponding to a Z-axis bridge arm on a wafer of a Z-axis magnetoresistive sensor. The Z-bridge arm includes a +Z bridge arm and / or a -Z bridge arm. The hard magnetic write head and a first soft magnetic shielding layer are located above and below the wafer of the Z-axis magnetoresistive sensor, respectively. The hard magnetic write head includes a substrate and a hard magnetic pole array disposed on the substrate. The magnetic moment direction of any hard magnetic pole is in the +Z or -Z direction, and the write end is directly opposite one of the Z-bridge arms. During writing, the hard magnetic pole write end generates a DC write magnetic field containing a Z-axis component in the pinned layer of the Z-bridge arm, thereby causing the magnetic moment of the pinned layer to steer in the direction of the Z-axis component DC write magnetic field.

[0011] In one embodiment, a microwave coil array is further included, with any microwave coil surrounding at least one of the hard magnetic poles; wherein, during writing, a microwave current passes through the microwave coil to generate a microwave magnetic field in the pinning layer of the Z-bridge arm.

[0012] In one embodiment, the substrate is a PCB, and the hard magnetic pole array is embedded in the PCB.

[0013] In one embodiment, the hard magnetic pole is: a prefabricated permanent magnet installed in a first PCB through-hole of the PCB; or a thick-film permanent magnet deposited in the first PCB through-hole by a gas flow sputtering method; or a composite permanent magnet formed by filling a mixture comprising permanent magnet powder and colloid in a second PCB through-hole, the second PCB through-hole comprising N-stage countersunk holes, wherein the first stage countersunk hole is located at the support end of the hard magnetic pole with a cross-sectional dimension of D1, the Nth stage countersunk hole is located at the writing end of the hard magnetic pole with a cross-sectional dimension of DN, and D1>D2…>DN, where N is an integer greater than or equal to 3; wherein the first PCB through-hole and the second PCB through-hole have circular or rectangular cross-sections.

[0014] In one embodiment, the substrate is a wafer, and the hard magnetic pole array is located above the wafer substrate.

[0015] In one embodiment, a second soft magnetic shielding layer is further included; the substrate is a PCB, the second soft magnetic shielding layer is located on the first surface layer of the PCB, and the hard magnetic pole support end penetrates through the second soft magnetic shielding layer; or, the substrate is a wafer, and the second soft magnetic shielding layer is located between the wafer substrate and the hard magnetic pole support end.

[0016] In one embodiment, a third soft magnetic shielding layer is further included; the substrate is a PCB, the third soft magnetic shielding layer is located on the second surface layer of the PCB, and the hard magnetic pole writing end penetrates through the third soft magnetic shielding layer; or, the substrate is a wafer, the third soft magnetic shielding layer is disposed near the end face of the hard magnetic pole writing end, and surrounds the hard magnetic pole writing end.

[0017] In one embodiment, the substrate is a PCB, and the hard magnetic writing head further includes a fourth soft magnetic shielding layer, which is located above the second soft magnetic shielding layer and the hard magnetic pole support end of the PCB.

[0018] In one embodiment, the system further includes an array of heating coils, the heating coils surrounding the hard magnetic pole writing end and maintaining a set gap between them and the hard magnetic pole, and each hard magnetic pole surrounding one of the heating coils.

[0019] In one embodiment, a heating coil array is further included, wherein the heating coils surround the hard magnetic pole writing end and maintain a set gap with the hard magnetic pole, and each hard magnetic pole surrounds one of the heating coils; during the writing of data of the magnetic moment of the pinned layer of the Z-axis magnetoresistive sensor, the heating coils and the microwave coils go through the following four stages: 1) The heating coils and the microwave coils are not energized; 2) The heating coils are energized and the microwave coils are not energized; 3) The heating coils are not energized and the microwave writing coils are energized; 4) The heating coils and the microwave coils are not energized.

[0020] In one embodiment, the Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor, including one of the +Z bridge arm and the -Z axis bridge arm and a reference bridge arm, and is a half-bridge, full-bridge, or quasi-bridge structure; or the Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor, including the +Z axis bridge arm and the -Z axis bridge arm, and is a half-bridge, full-bridge, or quasi-bridge structure.

[0021] In one embodiment, the cell writing region of the wafer of the Z-axis magnetoresistive sensor is a single die; the Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor with a full-bridge structure, and the hard magnetic pole array includes four hard magnetic poles, each corresponding to one of the four Z-bridge arms; or the Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor with a half-bridge or quasi-bridge structure; or the Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor with a full-bridge structure, and the hard magnetic pole array includes two hard magnetic poles, each corresponding to one of the two Z-bridge arms; or the Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor with a half-bridge or quasi-bridge structure, and the hard magnetic pole array includes one hard magnetic pole, corresponding to one Z-bridge arm.

[0022] In one embodiment, the unit write region of the wafer of the Z-axis magnetoresistive sensor is a single die; the Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor with a full-bridge structure, the hard magnetic pole array includes four hard magnetic poles, each corresponding to one of the four Z-bridge arms, and the microwave coil array includes one microwave coil surrounding the four hard magnetic poles; or the Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor with a half-bridge or quasi-bridge structure; or the Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor with a full-bridge structure, the hard magnetic pole array includes two hard magnetic poles, each corresponding to one of the two Z-bridge arms, and the microwave coil array includes one microwave coil surrounding the two hard magnetic poles; or the Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor with a half-bridge or quasi-bridge structure, the hard magnetic pole array includes one hard magnetic pole, corresponding to one Z-bridge arm, and the microwave coil array includes one microwave coil surrounding one hard magnetic pole.

[0023] In one embodiment, the cell writing area of ​​the wafer of the Z-axis magnetoresistive sensor is a mask exposure area, the mask exposure area contains M*N die arrays, and any die (m,n) includes k Z-bridge arms. The hard magnetic pole array includes M*N hard magnetic pole units, each hard magnetic pole unit includes k hard magnetic poles, 1≤m≤M, 1≤n≤N integers, and k=1, 2 or 4.

[0024] In one embodiment, the cell writing area of ​​the wafer of the Z-axis magnetoresistive sensor is a mask exposure area, the mask exposure area contains M*N die arrays, and any die (m,n) includes k Z-bridge arms. The hard magnetic pole array includes: M*N hard magnetic pole units, each hard magnetic pole unit includes k hard magnetic poles, and the k hard magnetic poles included in each hard magnetic pole unit are surrounded by a microwave coil, where 1≤m≤M, 1≤n≤N are integers, and k=1, 2 or 4.

[0025] In one embodiment, the unit writing area of ​​the wafer of the Z-axis magnetoresistive sensor is the entire wafer. The wafer includes an X*Y mask exposure area array. Each mask exposure area (x,y) includes an M1*N1 die array. Each die (x,y,m1,n1) includes k1 Z-bridge arms. The hard magnetic pole array includes X*Y*M1*N1 hard magnetic pole units. Each hard magnetic pole unit (x,y,m1,n1) includes k1 hard magnetic poles. X,Y,M1,N1 are all integers greater than 1, 1≤x≤X, 1≤y≤Y, 1≤m1≤M1, 1≤n1≤N1, and k1=1, 2, 4.

[0026] In one embodiment, the unit writing area of ​​the wafer of the Z-axis magnetoresistive sensor is the entire wafer. The wafer includes an X*Y mask exposure area array. Each mask exposure area (x,y) includes an M1*N1 die array. Each die (x,y,m1,n1) includes k1 Z-bridge arms. The hard magnetic pole array includes X*Y*M1*N1 hard magnetic pole units. Each hard magnetic pole unit (x,y,m1,n1) includes k1 hard magnetic poles. Each hard magnetic pole unit includes k1 hard magnetic poles surrounded by a microwave coil. X,Y,M1,N1 are all integers greater than 1, 1≤x≤X, 1≤y≤Y, 1≤m1≤M1, 1≤n1≤N1, and k1=1, 2, 4.

[0027] In one embodiment, when the cell writing area of the wafer of the Z-axis magnetoresistive sensor is the entire wafer, the wafer includes an M*N grain array, and any grain is the same and has k Z-bridge arms (1, …, k); the hard magnetic write head includes: M*[Pk]ceil(N / k) hard magnetic pole arrays, where [Pk] represents k X-direction adjacent arranged grain rows (D1, …, Dk) corresponding to k X-direction adjacent arranged hard magnetic pole unit rows (P1, …, Pk), wherein the Pi hard magnetic pole corresponds to the i-th Z-bridge arm of the Di grain, 1 = <i≤k is an integer, ceil(N / k) represents taking the smallest integer greater than N / k, and [Pk]ceil(N / k) represents the [Pk] hard magnetic pole unit rows repeating X-direction Ceil(N / k) times. During the writing operation, the hard magnetic write head moves k grain positions sequentially along the X-direction, and the writing operation of the entire wafer can be completed, where k = 1, 2, 4; or the hard magnetic write head includes: ceil(M / k)*N hard magnetic pole arrays, where [Pk]’ represents k Y-direction adjacent arranged grain columns (D1, …, Dk)’ corresponding to k Y-direction adjacent arranged hard magnetic pole unit columns (P1, …, Pk)’, wherein the Pi hard magnetic pole corresponds to the i-th Z-bridge arm of the Di grain, 1 = <i≤k is an integer, ceil(M / k) represents taking the smallest integer greater than M / k, and [Pk]’ceil(M / k) respectively represents the [Pk]’ hard magnetic pole unit columns repeating Y-direction Ceil(M / k) times. During the writing operation, the hard magnetic write head moves k grain positions sequentially along the Y-direction, and the writing operation of the entire wafer can be completed, where k = 1, 2, 4. Optionally, each hard magnetic pole can also surround a microwave coil.

[0028] In one embodiment, the Z-axis magnetoresistive sensor stack structure from bottom to top is: (Co / Pt)n / Ta / CoFeB / MgO / CoFeB / Ru / Ta, where the lower layer CoFeB is the pinned layer.

[0029] In one embodiment, the hard magnetic pole support end of the hard magnetic pole is connected to the output end of the microwave generator through a capacitor, and the ground end of the microwave generator is connected to the wafer substrate of the Z-axis magnetoresistive sensor to generate a microwave magnetic field at the gap between the hard magnetic pole writing end and the corresponding Z-bridge arm.

[0030] In one embodiment, the microwave coil, the microwave generator and the capacitor are connected in series, and the ground end of the DC power supply and the ground end of the microwave generator are connected to the wafer substrate of the Z-axis magnetoresistive sensor.

[0031] In one embodiment, a resistor is connected in series across the two ends of the microwave coil, and then a capacitor is connected in parallel, and the coil is powered by a DC power supply; or, a first capacitor is connected in series across the microwave coil, and then a second capacitor is connected in parallel, and the coil is powered by a DC power supply; or, the two ends of the microwave coil and the capacitor are connected in parallel, and the coil is powered by a square wave pulse power supply. In this embodiment, a microwave LC resonance is formed between the microwave coil and the capacitor to generate a microwave magnetic field, and the ground terminal of the DC power supply is connected to the wafer substrate of the Z-axis magnetoresistive sensor.

[0032] In one embodiment, the magnetic direction of the writing end of a portion of the hard magnetic poles in the hard magnetic pole array is opposite to the magnetic direction of the writing end of the remaining hard magnetic poles.

[0033] Secondly, embodiments of this application also provide a hard magnetic writing head device, comprising: the hard magnetic writing head of the first aspect above, or any possible implementation of the first aspect, and the first soft magnetic shielding layer.

[0034] Thirdly, embodiments of this application also provide a hard magnetic writing head device, comprising: a hard magnetic writing head device according to the second aspect; and a probe test stage; wherein, during the data writing process, the wafer of the Z-axis magnetoresistive sensor and the hard magnetic writing head are both placed on the probe test stage, the wafer of the Z-axis magnetoresistive sensor is placed on the XY wafer stage of the probe test stage, the hard magnetic writing head is placed on the probe holder of the probe test stage, and the first soft magnetic shield is located between the wafer of the Z-axis magnetoresistive sensor and the XY wafer stage, and the first soft... The magnetic shielding layer can be located on the back side of the Z-axis magnetoresistive sensor wafer or on the XY wafer stage; the hard magnetic write head and the unit write area of ​​the Z-axis magnetoresistive sensor wafer are positioned and aligned in the XY direction, and the write spacing in the Z direction is controlled by operating the probe test stage, and the write spacing between the hard magnetic write head and the Z-axis magnetoresistive sensor wafer is controlled at the working spacing; the hard magnetic write head is positioned and written sequentially in different unit write areas on the Z-axis magnetoresistive sensor wafer by operating the probe holder.

[0035] In one embodiment, the cell writing area is a single die on the wafer of the Z-axis magnetoresistive sensor, a mask exposure area, or the entire wafer.

[0036] In one embodiment, the system further includes an auxiliary heating device disposed on the wafer of the Z-axis magnetoresistive sensor or disposed on a probe test stage.

[0037] Fourthly, embodiments of this application also provide a method for manufacturing a write head, comprising: manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic poles are prefabricated permanent magnets mounted in a first PCB through-hole of a PCB substrate, the method comprising:

[0038] 1) Select a double-layer PCB, wherein a second soft magnetic shielding layer and a third soft magnetic shielding layer are respectively provided on the first and second surfaces of the PCB, and both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer; 2) Process a first through hole with a diameter of d, penetrating the double-layer PCB; 3) Process a stepped countersunk hole with a size of D (D>d), wherein the stepped countersunk hole and the first through hole are coaxial; process a first arc groove, a second arc groove, and a third arc groove, wherein the third soft magnetic shielding layer between the first arc groove and the stepped countersunk hole is a heating coil; the layer between the second arc groove and the third arc groove... The third soft magnetic shielding layer is a microwave coil. The stepped countersunk hole, the first arc groove, the second arc groove, and the third arc groove all penetrate the third soft magnetic shielding layer and extend into the PCB insulating layer; 4) Place a non-magnetic alignment plate to seal the stepped countersunk hole, and at the same time install the prefabricated permanent magnet in the first PCB through hole, so that the writing end of the prefabricated permanent magnet is aligned with the non-magnetic alignment plate; 5) Remove the non-magnetic alignment plate to obtain the hard magnetic pole array; 6) Deposit a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, and use a non-magnetic metal interlayer to transition between the second soft magnetic shielding layer and the fourth soft magnetic shielding layer.

[0039] Fifthly, this application also provides a method for manufacturing a write head, comprising: manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic poles are prefabricated permanent magnets installed in a first PCB through-hole of the PCB, the method comprising: selecting a double-layer PCB, wherein the first and second surface layers of the PCB correspond to a second soft magnetic shielding layer and a third soft magnetic shielding layer respectively, wherein both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer; 2) using PCB processing technology to fabricate on the third soft magnetic shielding layer: a heating coil, a microwave coil, and a hard magnetic pole window. 1) Separate the first through-hole and retain the third soft magnetic shielding layer between them; 2) Process the first PCB through-hole with a diameter of d, which passes through the double-layer PCB and the hard magnetic pole window; 3) Place a non-magnetic alignment plate to close the first through-hole, and install the prefabricated permanent magnet in the first PCB through-hole so that all the writing ends of the prefabricated permanent magnet are aligned with the non-magnetic alignment plate; 4) Remove the non-magnetic alignment plate to obtain the hard magnetic pole array; 5) Deposit a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, and use a non-magnetic metal interlayer to transition between the second soft magnetic shielding layer and the fourth soft magnetic shielding layer.

[0040] Sixthly, embodiments of this application also provide a method for manufacturing a write head, comprising: manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic poles are thick-film permanent magnets deposited in a first PCB via in a PCB substrate by gas flow sputtering, the method comprising:

[0041] 1) Select a double-layer PCB, wherein a second soft magnetic shielding layer and a third soft magnetic shielding layer are respectively provided on the first and second surfaces of the PCB. Both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer; 2) Machining a stepped countersunk hole with a size of D (D>d), wherein the stepped countersunk hole and the first through hole are coaxial; machining a first circular arc groove, a second circular arc groove, and a third circular arc groove, wherein the third soft magnetic shielding layer between the first circular arc groove and the stepped countersunk hole is the heating coil; the third soft magnetic shielding layer between the second circular arc groove and the third circular arc groove is the microwave coil, wherein the stepped countersunk hole, the first circular arc groove, the second circular arc groove, and the third circular arc groove all penetrate through the microwave coil. The third soft magnetic shielding layer extends into the PCB insulating layer; 3) Photoresist is used as a sacrificial layer to cover the second surface layer of the PCB; 4) The first PCB via with a diameter of d is processed, penetrating the PCB and the photoresist layer, and coaxial with the stepped countersunk hole; 5) The double-layer PCB is placed on the substrate, the end of the stepped countersunk hole is aligned with the target of the gas flow sputtering thick film deposition equipment, and the hard magnetic thick film is deposited until the via is filled; 6) The photoresist is removed to obtain a write head containing the hard magnetic poles of the hard magnetic thick film; 7) A fourth soft magnetic shielding layer is deposited on the second soft magnetic shielding layer, and a non-magnetic metal interlayer is used to transition between the second soft magnetic shielding layer and the fourth soft magnetic shielding layer.

[0042] Seventhly, embodiments of this application also provide a method for manufacturing a write head, comprising: manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic poles are thick-film permanent magnets deposited in a first PCB via in a PCB substrate by gas flow sputtering, the method comprising:

[0043] 1) Select a double-layer PCB, wherein a second soft magnetic shielding layer and a third soft magnetic shielding layer are respectively provided on the first and second surfaces of the PCB, and both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer; 2) Use PCB processing technology to fabricate a heating coil, a microwave coil, and a hard magnetic pole window on the third soft magnetic shielding layer, while retaining the third soft magnetic shielding layers between them; 3) Spray photoresist as a sacrificial layer to cover the second surface of the PCB; 4) Process the first PCB via with a diameter of d, penetrating the PCB and the photoresist layer, and coaxial with the stepped countersunk hole; 5) Place the double-layer PCB on the substrate, align the end of the stepped countersunk hole with the target of the gas flow sputtering thick film deposition equipment, and begin depositing the hard magnetic thick film until the via is filled; 6) Remove the photoresist to obtain a write head containing the hard magnetic pole of the hard magnetic thick film; 7) Deposit a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, with a non-magnetic metal intermediate layer as a transition between the second and fourth soft magnetic shielding layers.

[0044] Eighthly, embodiments of this application also provide a method for manufacturing a write head, comprising: manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic head is a composite permanent magnet formed by filling a mixture comprising permanent magnet powder and colloid in a second PCB via in a PCB substrate, the method comprising:

[0045] 1) Select a double-layer PCB, wherein a second soft magnetic shielding layer and a third soft magnetic shielding layer are respectively provided on the first and second surface layers of the PCB, and both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer.

[0046] 2) Using cutting tools of different diameters, process the second PCB through-hole from the first surface layer to the second surface layer;

[0047] 3) Seal the stepped opening of the second PCB through-hole on the second surface layer using a non-magnetic transparent alignment plate, and place an alignment permanent magnet on the other side of the non-magnetic transparent alignment plate so that the composite permanent magnet has a +Z or -Z polarity; 4) Mix permanent magnet powder and colloid to form a mixture, disperse it on the first surface layer, fill the mixture into the second PCB through-hole, and remove excess magnetic powder; 5) Remove the non-magnetic transparent alignment plate; 6) Process a stepped countersunk hole with a size of D (D>d), the stepped countersunk hole and the second through-hole being coaxial; The first, second, and third circular arc grooves are formed, and the third soft magnetic shielding layer between the first circular arc groove and the stepped countersunk hole is the heating coil; the third soft magnetic shielding layer between the second and third circular arc grooves is the microwave coil, and the stepped countersunk hole, the first circular arc groove, the second circular arc groove, and the third circular arc groove all penetrate the third soft magnetic shielding layer and extend into the PCB insulation layer; 7) A fourth soft magnetic shielding layer is deposited on the second soft magnetic shielding layer, and a non-magnetic metal interlayer is used for transition between the second soft magnetic shielding layer and the fourth soft magnetic shielding layer.

[0048] Ninthly, embodiments of this application also provide a method for manufacturing a write head, comprising: manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic head is a composite permanent magnet formed by filling a mixture comprising permanent magnetic powder and colloid in a second PCB via in a PCB substrate, the method comprising: 1) selecting a double-layer PCB, wherein a second soft magnetic shielding layer and a third soft magnetic shielding layer are respectively provided on the first and second surface layers of the PCB, wherein both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer; 2) using cutting tools of different diameters to process the second PCB via from the first surface layer to the second surface layer; 3) using a non-magnetic transparent alignment plate to seal the second PCB via located on the second surface layer. Step opening, and place alignment permanent magnets on the other side of the non-magnetic transparent alignment plate so that the composite permanent magnets have +Z or -Z polarity; 4) Mix permanent magnet powder and colloid to form a mixture and disperse it on the first surface layer, fill the mixture into the second PCB through hole, and remove excess magnetic powder; 5) Remove the non-magnetic transparent alignment plate; 6) Remove the non-magnetic transparent alignment plate; 7) Use PCB processing technology to prepare the heating coil, microwave coil, and hard magnetic pole window on the third soft magnetic shielding layer, and retain the third soft magnetic shielding layer between them; 8) Deposit a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, and use a non-magnetic metal interlayer to transition between the second soft magnetic shielding layer and the fourth soft magnetic shielding layer.

[0049] Tenthly, embodiments of this application also provide a method for manufacturing a write head, comprising: manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic poles are thick-film permanent magnets deposited in vias in a wafer substrate by gas flow sputtering, the method comprising: 1) depositing a second soft magnetic shielding layer on the wafer by gas flow sputtering, wherein a non-magnetic metal interlayer is used as a transition between the second soft magnetic shielding layer and the wafer; 2) depositing a wet etching stop layer for the permanent magnet thick-film hard magnetic poles: a SiO2, Si3N4, or Al2O3 thin film. 3) Deposit a thick-film permanent magnet using a gas flow sputtering method; 4) Use photoresist as a mask to form an etching window for the hard magnetic poles of the thick-film permanent magnet; 5) Wet etch the thick-film permanent magnet and remove the photoresist to obtain the hard magnetic pole array of the thick-film permanent magnet; 6) Fill the gaps and surface of the hard magnetic pole array of the thick-film permanent magnet with polyimide, solidify and planarize it; 7) Thin the polyimide using reactive ion etching (RIE); 8) Sputter a seed layer; 9) Electroplat the heating coil, microwave coil, and third soft magnetic shielding layer; 10) Remove the seed layer to obtain the write head.

[0050] The hard magnetic write head provided in this application, when facing the pinned layer of the Z-bridge arm corresponding to the Z-axis magnetoresistive sensing unit array on the wafer of the Z-axis magnetoresistive sensor, generates a DC write magnetic field containing a Z-axis component in the pinned layer of the Z-bridge arm, thereby causing the magnetic moment of the pinned layer to align with the direction of the DC write magnetic field of the Z-axis component. This provides a simple, fast, and efficient method for writing the magnetic moment of the reference layer of the Z-axis magnetoresistive sensor.

[0051] In embodiments where the magnetic poles are also surrounded by microwave coils, the microwave coils can enhance the magnetic field strength, including the Z-axis component of the DC writing magnetic field, generated in the pinning layer of the Z-bridge arm, thereby improving the efficiency and effectiveness of magnetic moment writing.

[0052] Furthermore, during the fabrication of the hard magnetic pole array, some hard magnetic poles can be fabricated with the N-pole as the writing end, while others can be fabricated with the S-pole as the writing end. This allows the hard magnetic writing head to write to the unit writing area of ​​the Z-axis magnetoresistive sensor wafer, enabling the writing of magnetic moments in opposite directions at different locations within the unit writing area. In this embodiment, if the hard magnetic poles are also surrounded by a microwave coil, the direction of the current flowing through the microwave coil should be compatible with the magnetism of the hard magnetic pole writing end; that is, the direction of the magnetic field generated by the microwave coil should be consistent with the direction of the magnetic field generated by the hard magnetic pole writing end. Attached Figure Description

[0053] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 The hard magnetic write head provided in the embodiments of this application is a front view of structure one plus method one;

[0055] Figure 2 The hard magnetic write head provided in the embodiments of this application is a structural front view of structure one plus setting one;

[0056] Figure 3 The hard magnetic write head provided in the embodiments of this application is a front view of structure one plus setting one and setting three;

[0057] Figure 4 Provided for the embodiments of this application Figure 3 Structural bottom view;

[0058] Figure 5 The hard magnetic write head provided in the embodiments of this application is a front view of a structure consisting of structure one plus setting one, setting three, and setting five;

[0059] Figure 6 The hard magnetic write head provided in the embodiments of this application is another structural front view of structure one plus setting one, setting three and setting five;

[0060] Figure 7 The hard magnetic write head provided in the embodiments of this application is a front view of structure two plus setting one and setting three;

[0061] Figure 8 Provided for the embodiments of this application Figure 7 Structural bottom view;

[0062] Figure 9 The hard magnetic write head provided in the embodiments of this application is a front view of a structure with structure four plus setting one and setting three;

[0063] Figure 10 Provided for the embodiments of this application Figure 9 Structural bottom view;

[0064] Figure 11 The hard magnetic write head provided in this embodiment of the application is a front view of structure four plus setting two and setting four;

[0065] Figure 12 A schematic diagram of a method corresponding to the PCB write head processing technology provided in the embodiments of this application;

[0066] Figure 13 This is a schematic diagram of Method 2 corresponding to the PCB write head processing technology provided in the embodiments of this application;

[0067] Figure 14 This is a schematic diagram of Method 3 corresponding to the PCB writing head processing technology provided in the embodiments of this application;

[0068] Figure 15 This is a schematic diagram of method four corresponding to the PCB writing head processing technology provided in the embodiments of this application;

[0069] Figure 16 A schematic diagram of the thick film deposition principle using gas flow sputtering provided in this application embodiment;

[0070] Figure 17 This is a schematic diagram of a gas flow sputtering deposition apparatus provided in an embodiment of this application;

[0071] Figure 18 A schematic diagram of sputtering a hard magnetic thick film in a first through-hole of a PCB using the gas flow sputtering method provided in an embodiment of this application;

[0072] Figure 19 A schematic diagram of direct sputtering of hard magnetic thick films on a wafer using the gas flow sputtering method provided in this application embodiment;

[0073] Figure 20 This is a schematic diagram of method five corresponding to the wafer write head processing technology provided in the embodiments of this application;

[0074] Figure 21 This is a schematic diagram of method six corresponding to the PCB writing head processing technology provided in the embodiments of this application;

[0075] Figure 22 A schematic diagram of method seven corresponding to the PCB write head processing technology provided in the embodiments of this application;

[0076] Figure 23 The magnetic field line distribution diagram of the hard magnetic poles provided in the embodiments of this application;

[0077] Figure 24 The distribution diagram of By and Bx of hard magnetic poles at the Z-bridge arm position provided in the embodiments of this application;

[0078] Figure 25 This is a magnetic field distribution diagram of the combination of hard magnetic poles and a first soft magnetic shielding layer provided in an embodiment of this application;

[0079] Figure 26 A distribution diagram of By and Bx of the hard magnetic pole and the first soft magnetic shielding layer combination provided in the embodiments of this application at the Z-bridge arm position;

[0080] Figure 27A magnetic field distribution diagram of the combination of hard magnetic poles, first soft magnetic shielding layer, and second soft magnetic shielding layer provided in an embodiment of this application;

[0081] Figure 28 Distribution diagram of By and Bx of hard magnetic poles, first soft magnetic shielding layer and second soft magnetic shielding layer at the Z-bridge arm position provided in the embodiments of this application;

[0082] Figure 29 A magnetic field distribution diagram of the combination of hard magnetic poles, first soft magnetic shielding layer, second soft magnetic shielding layer, and third soft magnetic shielding layer provided for embodiments of this application;

[0083] Figure 30 The distribution diagram of By and Bx at the Z-arm position of the combination of hard magnetic poles, first soft magnetic shielding layer, second soft magnetic shielding layer, and third soft magnetic shielding layer provided in the embodiments of this application;

[0084] Figure 31 A magnetic field distribution diagram of the combined stepped hard magnetic pole, first soft magnetic shielding layer, second soft magnetic shielding layer, and third soft magnetic shielding layer provided for embodiments of this application;

[0085] Figure 32 The distribution diagram of By and Bx at the Z-arm position of the combination of stepped hard magnetic pole, first soft magnetic shielding layer, second soft magnetic shielding layer and third soft magnetic shielding layer provided in the embodiments of this application;

[0086] Figure 33 A spatial distribution diagram of combined magnetic field lines of hard magnetic poles, first soft magnetic shielding layer, penetrating second soft magnetic shielding layer, and third soft magnetic shielding layer provided for embodiments of this application;

[0087] Figure 34 A distribution diagram of By and Bx at the Z-arm position of the combination of hard magnetic poles, first soft magnetic shielding layer, penetrating second soft magnetic shielding layer, and third soft magnetic shielding layer provided in the embodiments of this application;

[0088] Figure 35 Spatial distribution diagram of combined magnetic field lines of hard magnetic poles, first soft magnetic shielding layer, penetrating second soft magnetic shielding layer, third soft magnetic shielding layer, and fourth soft magnetic shielding layer provided for embodiments of this application;

[0089] Figure 36 The distribution diagram of By and Bx at the Z-arm position of the combination of hard magnetic pole, first soft magnetic shielding layer, penetrating second soft magnetic shielding layer, third soft magnetic shielding layer, and fourth soft magnetic shielding layer provided for the embodiments of this application;

[0090] Figure 37 The typical Z-axis magnetoresistive sensor sensing unit stacking structure provided in the embodiments of this application includes: a) specific structure and b) simplified structure.

[0091] Figure 38A schematic diagram of the rotation of the magnetic moment of the pinning layer under the action of the Z magnetic field, provided in an embodiment of this application;

[0092] Figure 39 A schematic diagram of the rotation of the magnetic moment of the pinned layer under the combined action of a microwave magnetic field and a DC magnetic field, provided in an embodiment of this application; wherein, a) is a diagram of the writing head device of the permanent magnet hard magnetic pole and the microwave coil; b) is a diagram of the rotation of the magnetic moment under the action of a microwave magnetic field and a DC magnetic field;

[0093] Figure 40 The diagram shows the structure of a push-pull Z-axis magnetoresistive sensor provided in the embodiments of this application; wherein, a) is a full-bridge structure, b) is a half-bridge structure, and c) is a quasi-bridge structure;

[0094] Figure 41 The following is a structural diagram of a reference bridge Z-axis magnetoresistive sensor provided in an embodiment of this application; wherein, a) is a full-bridge structure, b) is a half-bridge structure, and c) is a quasi-bridge structure;

[0095] Figure 42 The single-grain diagram corresponding to the write head provided in the embodiments of this application; wherein, a) is 4 Z-bridge arms, b) is 2 Z-bridge arms, and c) is 1 Z-bridge arm;

[0096] Figure 43 This is a diagram of a single exposure area on a wafer corresponding to the write head, provided in an embodiment of this application.

[0097] Figure 44 This application provides a diagram of the entire wafer region corresponding to the write head in an embodiment of the present application.

[0098] Figure 45 The write head provided in this embodiment corresponds to the entire wafer area. Figure 1 Wherein, a) is the distribution diagram of hard magnetic poles on the grain, b) is the writing phase 1, c) is the writing phase 2, d) is the writing phase 3, and e) is the writing phase 4.

[0099] Figure 46 The following diagram illustrates the writing operation of the write head on the wafer of the Z-axis magnetoresistive sensor provided in this embodiment: a) Alignment, b) Writing.

[0100] Figure 47 The wafer circuit for writing Z-axis magnetoresistive sensors using a write head provided in the embodiments of this application. Figure 1 ;

[0101] Figure 48 The wafer circuit for writing Z-axis magnetoresistive sensors using a write head provided in the embodiments of this application. Figure 2 ;

[0102] Figure 49 The wafer circuit for writing Z-axis magnetoresistive sensors using a write head provided in the embodiments of this application. Figure 3 ;

[0103] Figure 50 The wafer circuit for writing Z-axis magnetoresistive sensors using a write head provided in the embodiments of this application. Figure 4 ;

[0104] Figure 51 The timing diagram for the write coil operation provided in the embodiments of this application is shown. Detailed Implementation

[0105] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0106] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0107] Firstly, this application provides a hard magnetic write head for writing the magnetic moment of the pinned layer of the Z-axis magnetoresistive sensing unit array corresponding to the Z-bridge arm on the wafer of a Z-axis magnetoresistive sensor. The bridge arm includes a +Z bridge arm and / or a -Z bridge arm. The hard magnetic write head and the first soft magnetic shielding layer are located above and below the wafer of the Z-axis magnetoresistive sensor, respectively.

[0108] For example, the Z-axis magnetoresistive sensor stack structure from bottom to top can be: (Co / Pt)n / Ta / CoFeB / MgO / CoFeB / Ru / Ta, where the lower CoFeB layer is a pinning layer.

[0109] Alternatively, the hard magnetic write head can be implemented in various ways, including but not limited to the following:

[0110] Structure 1: The hard magnetic write head includes a substrate and a hard magnetic pole array disposed on the substrate.

[0111] The hard magnetic pole array here includes multiple hard magnetic poles. The magnetic moment direction of any hard magnetic pole is in the +Z or -Z direction, and the write end is directly opposite a Z-bridge arm.

[0112] It should be understood that during writing, the hard magnetic pole writing end generates a DC writing magnetic field containing a Z-axis component in the pinning layer of the Z-bridge arm, thereby causing the magnetic moment of the pinning layer to align in the direction of the Z-axis component DC writing magnetic field.

[0113] In one embodiment, the cell writing area of the wafer of the Z-axis magnetoresistive sensor is the mask exposure area. The mask exposure area includes an array of M*N grains, and any grain (m,n) includes k Z-bridge arms. The hard magnetic pole array includes: M*N hard magnetic pole units, and each hard magnetic pole unit includes k of the hard magnetic poles, where 1≤m≤M, 1≤n≤N are integers, and k = 1, 2 or 4.

[0114] In another embodiment, the cell writing area of the wafer of the Z-axis magnetoresistive sensor is the entire wafer. The wafer includes an array of X*Y mask exposure areas. Any mask exposure area (x,y) includes an array of M1*N1 grains. Any grain (x,y,m1,n1) includes k1 Z-bridge arms. The hard magnetic pole array includes: X*Y*M1*N1 hard magnetic pole units. Any hard magnetic pole unit (x,y,m1,n1) includes: k1 of the hard magnetic poles. X, Y, M1, N1 are all integers greater than 1, 1≤x≤X is an integer, 1≤y≤Y is an integer, 1≤m1≤M1 is an integer, 1≤n1≤N1 is an integer, and k1 = 1, 2, 4.

[0115] In other embodiments, when the cell writing area of the wafer of the Z-axis magnetoresistive sensor is the entire wafer, the wafer includes an array of M*N grains, and any grain is the same and has k Z-bridge arms (1,…,k).

[0116] The hard magnetic write head may further include: M*[Pk]ceil(N / k) hard magnetic pole arrays. [Pk] represents k rows of hard magnetic pole units (P1,…,Pk) corresponding to k adjacent rows of grains (D1,…,Dk) arranged in the X direction. The Pi hard magnetic pole corresponds to the i-th Z-bridge arm of the Di grain, where 1≤i≤k is an integer, ceil(N / k) represents the smallest integer greater than N / k, and [Pk]ceil(N / k) represents the [Pk] rows of hard magnetic pole units repeated ceil(N / k) times in the X direction. During the writing operation, the hard magnetic write head moves k grain positions in sequence along the X direction to complete the writing operation of the entire wafer, where k = 1, 2, 4.

[0117] Alternatively, the hard magnetic write head may further include: ceil(M / k)*N hard magnetic pole arrays, where [Pk]’ represents k Y-direction adjacent arranged hard magnetic pole unit columns (P1,…,Pk)’ corresponding to k Y-direction adjacent arranged grain columns (D1,…,Dk)’, where the Pi hard magnetic pole corresponds to the i-th Z-bridge arm of the Di grain, 1 ≤ i ≤ k is an integer, ceil(M / k) represents the smallest integer greater than M / k, and [Pk]’ceil(M / k) respectively represents that the [Pk]’ hard magnetic pole unit column repeats Ceil(M / k) times in the Y direction. During the writing operation, the hard magnetic write head moves k grain positions in the Y direction in sequence to complete the writing operation on the entire wafer, where k = 1, 2, 4.

[0118] Structure Two: The hard magnetic write head includes: a substrate, a hard magnetic pole array disposed on the substrate, and a microwave coil array.

[0119] The hard magnetic pole array here includes multiple hard magnetic poles, and the microwave coil array includes multiple microwave coils. Among them, any one microwave coil surrounds at least one hard magnetic pole.

[0120] It should be understood that during writing, a microwave current passes through the microwave coil to generate a microwave magnetic field in the pinned layer of the Z-bridge arm.

[0121] In one embodiment, the unit writing area of the wafer of the Z-axis magnetoresistive sensor is the mask exposure area. This mask exposure area contains M*N grain arrays, and any grain (m,n) includes k Z-bridge arms. The hard magnetic pole array includes: M*N hard magnetic pole units, each hard magnetic pole unit includes k of the hard magnetic poles, and the k hard magnetic poles included in each hard magnetic pole unit are surrounded by one microwave coil, 1 ≤ m ≤ M, 1 ≤ n ≤ N are integers, and k = 1, 2 or 4.

[0122] In another embodiment, the unit writing area of the wafer of the Z-axis magnetoresistive sensor is the entire wafer. This wafer includes an array of X*Y mask exposure areas, any mask exposure area (x,y) includes M1*N1 grain arrays, and any grain (x,y,m1,n1) includes k1 Z-bridge arms. The hard magnetic pole array includes: X*Y*M1*N1 hard magnetic pole units, and any hard magnetic pole unit (x,y,m1,n1) includes: k1 hard magnetic poles, and the k1 hard magnetic poles included in each hard magnetic pole unit are surrounded by one microwave coil, X, Y, M1, N1 are all integers greater than 1, 1 ≤ x ≤ X is an integer, 1 ≤ y ≤ Y is an integer, 1 ≤ m1 ≤ M1 is an integer, 1 ≤ n1 ≤ N1 is an integer, and k1 = 1, 2, 4.

[0123] Structure Three: The hard magnetic write head includes: a substrate, a hard magnetic pole array disposed on the substrate, and a heating coil array.

[0124] The hard magnetic pole array here includes multiple hard magnetic poles, and the heating coil array includes multiple heating coils. The heating coils surround the writing end of the hard magnetic poles and maintain a set gap with the hard magnetic poles, with each hard magnetic pole surrounding one heating coil.

[0125] The heating coils described above are used to heat the Z-axis bridge arm to a target temperature. This target temperature can be in the range of 150°C to 300°C, for example, target temperatures of 180°C, 200°C, 220°C, etc.

[0126] Structure 4: The hard magnetic writing head includes: a substrate, a hard magnetic pole array disposed on the substrate, a microwave coil array, and a heating coil array.

[0127] The hard magnetic pole array here includes multiple hard magnetic poles, the microwave coil array includes multiple microwave coils, and the heating coil array includes multiple heating coils. Each microwave coil surrounds at least one hard magnetic pole, and each heating coil surrounds the writing end of a hard magnetic pole, maintaining a predetermined gap between them. Each hard magnetic pole surrounds one heating coil. Optionally, this predetermined gap can be in the range of 1–15 μm, for example, values ​​of 1 μm, 5 μm, 10 μm, 12 μm, 15 μm, etc.

[0128] It should be understood that the microwave coil and the heating coil can be independent and different coils, or they can be the same coil. Alternatively, some of the heating coils may be the same coil as the microwave coil, while others may be different coils independent of the microwave coil. When the microwave coil and the heating coil are the same coil, this can be achieved by using different operating timing sequences of the microwave generator and the heating power supply connected to that same coil.

[0129] In the process of writing data for the magnetic moment of the pinned layer of the Z-axis magnetoresistive sensor, the heating coil and microwave coil go through the following four stages:

[0130] 1) The heating coil and microwave coil are not energized;

[0131] 2) The heating coil is energized, but the microwave coil is not energized;

[0132] 3) The heating coil is not energized, but the microwave writing coil is energized;

[0133] 4) The heating coil and microwave coil are not energized.

[0134] In stage 2), the temperature of the Z-bridge arm is rapidly raised to the write temperature and maintained in stage 3) so that the write operation of the Z-bridge arm magnetic moment can be performed in stage 3.

[0135] In the above four structures, the substrate can be arranged in various ways, including but not limited to the following:

[0136] Form 1: The substrate is a PCB, and the hard magnetic pole array is embedded in the PCB.

[0137] In one embodiment, the hard magnetic pole can be: a prefabricated permanent magnet installed in a first PCB through-hole of the PCB; or a thick-film permanent magnet deposited in the first PCB through-hole by a gas flow sputtering method; or a composite permanent magnet formed by filling a mixture comprising permanent magnet powder and colloid in a second PCB through-hole, wherein the second PCB through-hole comprises an N-stage countersunk hole, with the first stage countersunk hole located at the hard magnetic pole support end and having a cross-sectional dimension of D1, and the Nth stage countersunk hole located at the hard magnetic pole writing end and having a cross-sectional dimension of DN, where D1>D2…>DN, and N is an integer greater than or equal to 3. The first PCB through-hole and the second PCB through-hole have circular or rectangular cross-sections.

[0138] Form 2: The substrate is a wafer, and the hard magnetic pole array is located above the wafer substrate.

[0139] In one embodiment, if the hard magnetic writing head has any one of the structures described in Structure 1 to Structure 4, the hard magnetic pole support end of the hard magnetic pole is connected to the output end of the microwave generator through a capacitor, and the ground end of the microwave generator is connected to the wafer substrate of the Z-axis magnetoresistive sensor to generate a microwave magnetic field in the gap between the hard magnetic pole writing end and the corresponding Z-axis bridge arm.

[0140] In another embodiment, if the hard magnetic writing head has the structure of structure two or structure four described above, then the microwave coil, microwave generator and capacitor are connected in series, and the ground terminal of the DC power supply and the ground terminal of the microwave generator are connected to the wafer substrate of the Z-axis magnetoresistive sensor.

[0141] In other embodiments, if the hard magnetic write head has the structure of structure two or four described above, a resistor is connected in series across the two ends of the microwave coil, and then connected in parallel with a capacitor, and then powered by a DC power supply; or, a first capacitor is connected in series with the microwave coil, and then connected in parallel with a second capacitor, and then powered by a DC power supply; or, the two ends of the microwave coil and the capacitor are connected in parallel, and then powered by a square wave pulse power supply. In this configuration, a microwave LC resonance is formed between the microwave coil and the capacitor to generate a microwave magnetic field, and the ground terminal of the DC power supply is connected to the wafer substrate of the Z-axis magnetoresistive sensor.

[0142] It should be understood that the above structures one to four are the basic structures of hard magnetic write heads. Based on the above structures one to four, the hard magnetic write head may also include any one of the following: a second soft magnetic shielding layer, a third soft magnetic shielding layer, or a fourth soft magnetic shielding layer. Different hard magnetic write heads correspond to different substrate methods.

[0143] Specifically, when the hard magnetic write head also includes any one of a second soft magnetic shielding layer, a third soft magnetic shielding layer, or a fourth soft magnetic shielding layer, the substrate can be configured as follows:

[0144] Setting 1: When the hard magnetic write head is also provided with a second soft magnetic shielding layer and the substrate is a PCB: the second soft magnetic shielding layer is located on the first surface layer of the PCB, and the hard magnetic pole support end penetrates through the second soft magnetic shielding layer.

[0145] Setting 2: When the hard magnetic write head is also provided with a second soft magnetic shielding layer, and the substrate is a wafer: the second soft magnetic shielding layer is located between the wafer substrate and the hard magnetic pole support end.

[0146] Setting 3: When the hard magnetic write head is also provided with a third soft magnetic shielding layer and the substrate is a PCB: the third soft magnetic shielding layer is located on the second surface layer of the PCB, and the hard magnetic pole writing end penetrates through the third soft magnetic shielding layer.

[0147] Setting 4: When the hard magnetic write head is also provided with a third soft magnetic shielding layer and the substrate is a wafer: the third soft magnetic shielding layer is located at the end face near the hard magnetic pole write end and surrounds the hard magnetic pole write end.

[0148] Setting 5: When the hard magnetic writing head is also provided with a fourth soft magnetic shielding layer and the substrate is a PCB: the fourth soft magnetic shielding layer is located above the second soft magnetic shielding layer and the hard magnetic pole support end of the PCB.

[0149] It should be understood that the specific arrangement of the substrate described above can be combined with any of the hard magnetic write heads described above. When there is no conflict between the above arrangements, multiple arrangements can also be combined to form multiple hard magnetic write head structures. For example, the specific structure of the hard magnetic write head can be: Structure 1 + Arrangement 1, Structure 1 + Arrangement 2, Structure 1 + Arrangement 1 + Arrangement 3, Structure 1 + Arrangement 3, Structure 1 + Arrangement 4, Structure 1 + Arrangement 2 + Arrangement 4, Structure 1 + Arrangement 5... Structure 3 + Arrangement 4, Structure 3 + Arrangement 5, etc.

[0150] When combining the above-mentioned various structures and configurations, conflicting configurations cannot be combined. Here, conflict refers to a substrate corresponding to only one type in each structure. For example, when the substrate is configured as configuration one, it cannot be configured as configuration two or four. When the substrate is configured as configuration two, it cannot be configured as configuration one, configuration three, or configuration five.

[0151] Optionally, when the hard magnetic writing head includes a third soft magnetic shielding layer and a heating coil, the heating coil is located between the third soft magnetic shielding layer and the hard magnetic pole.

[0152] Optionally, when the hard magnetic writing head includes a third soft magnetic shielding layer, a microwave coil, and a heating coil, the microwave coil divides the third soft magnetic shielding layer into inner and outer parts, and the heating coil is located inside the microwave coil.

[0153] The aforementioned Z-axis magnetoresistive sensor can be a reference bridge magnetoresistive sensor, including one of the +Z and -Z axis bridge arms and a reference bridge arm, and can be a half-bridge, full-bridge, or quasi-bridge structure. The Z-axis magnetoresistive sensor can also be a push-pull bridge magnetoresistive sensor, including a +Z axis bridge arm and a -Z axis bridge arm, and can be a half-bridge, full-bridge, or quasi-bridge structure. The specific structure of the Z-axis magnetoresistive sensor can be selected according to actual conditions, and this application does not impose specific limitations.

[0154] For example, the hard magnetic write head is structure one, and the unit write region of the wafer of the Z-axis magnetoresistive sensor is a single die. Therefore, the specific structure of the Z-axis magnetoresistive sensor can be as follows:

[0155] Structure A: If the Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor and is a full-bridge structure, the hard magnetic pole array includes 4 hard magnetic poles, which correspond to the 4 Z-bridge arms respectively.

[0156] Structure B: The Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor, and is a half-bridge or quasi-bridge structure; or, the Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor, and is a full-bridge structure; the hard magnetic pole array includes two hard magnetic poles, each corresponding to one of the two Z-bridge arms.

[0157] Structure C: The Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor, and it is a half-bridge or quasi-bridge structure. The hard magnetic pole array includes one hard magnetic pole, corresponding to one Z-bridge arm.

[0158] For example, the hard magnetic write head is structure two, and the unit write region of the wafer of the Z-axis magnetoresistive sensor is a single die. Therefore, the specific structure of the Z-axis magnetoresistive sensor can be as follows:

[0159] Structure D: The Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor with a full-bridge structure. The hard magnetic pole array includes four hard magnetic poles, each corresponding to one of the four Z-bridge arms. The microwave coil array includes one microwave coil that surrounds the four hard magnetic poles.

[0160] Structure E: The Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor, and is a half-bridge or quasi-bridge structure; or, the Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor, and is a full-bridge structure. The hard magnetic pole array includes two hard magnetic poles, each corresponding to one of the two Z-bridge arms. The microwave coil array includes one microwave coil surrounding the two hard magnetic poles.

[0161] Structure F: The Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor, and is a half-bridge or quasi-bridge structure. The hard magnetic pole array includes one hard magnetic pole, corresponding to one Z-bridge arm. The microwave coil array includes one microwave coil surrounding one hard magnetic pole.

[0162] The structures 1 to 4, methods 1 to 2, settings 1 to 5, and structures A to F described above can be combined or disassembled to obtain a variety of hard magnetic write head structures.

[0163] In some embodiments, the magnetic direction of the writing end of a portion of the hard magnetic poles in the hard magnetic pole array is opposite to the magnetic direction of the writing end of the remaining hard magnetic poles.

[0164] For example, when fabricating a hard magnetic pole array, some hard magnetic poles can be fabricated with the N-pole as the writing end, while others can be fabricated with the S-pole as the writing end. Then, when the hard magnetic writing head performs a writing operation on the unit writing area of ​​the Z-axis magnetoresistive sensor wafer, magnetic moments in opposite directions can be written at different positions within the unit writing area. In this embodiment, if the hard magnetic poles are also surrounded by a microwave coil, the direction of the current flowing through the microwave coil should be compatible with the magnetism of the hard magnetic pole writing end; that is, the direction of the magnetic field generated by the microwave coil should be consistent with the direction of the magnetic field generated by the hard magnetic pole writing end.

[0165] The following diagram illustrates the specific structure of some hard magnetic write heads:

[0166] Example 1: Figure 1 The hard magnetic write head shown is a structure of structure one plus method one, which includes: substrate 2 and hard magnetic pole array 3.

[0167] The substrate 2 here is a PCB, and it is a non-magnetic layer. The hard magnetic pole array 3 is embedded in the substrate PCB and penetrates the PCB. The write end 24 of the hard magnetic pole array 3 faces the Z-bridge arm array 6 on the wafer 5. For example, the write end of the hard magnetic pole 33 faces the Z-bridge arm 63, the write end of the hard magnetic pole 32 faces the Z-bridge arm 62, the write end of the hard magnetic pole 31 faces the Z-bridge arm 61, and the write end of the hard magnetic pole 30 faces the Z-bridge arm 60. 25 is the hard magnetic pole support end. The hard magnetic poles have magnetic moments in the +Z or -Z direction. A first soft magnetic shielding layer 4 is also provided on the side of the wafer 5 away from the hard magnetic write head.

[0168] Example 2: Figure 2 The hard magnetic write head shown is a structure with one structure plus one setting. The structure includes: substrate 2 (1), second soft magnetic shielding layer 8, first metal intermediate layer 7 and hard magnetic pole array 3.

[0169] The substrate 2(1) here is a PCB, which can be regarded as a single-layer board, including: a non-magnetic layer 2', a second soft magnetic shielding layer 8 located at the first surface layer 301 of the PCB and a first metal intermediate layer 7, a hard magnetic pole array 3 embedded in the substrate 2(1) and penetrating the substrate 2(1), wherein the writing end 24 of the hard magnetic pole array 3 is facing the Z bridge arm array 6 on the wafer 5, such as the writing end of the hard magnetic pole 33 facing the Z bridge arm 63, the writing end of the hard magnetic pole 32 facing the Z bridge arm 62, the writing end of the hard magnetic pole 31 facing the Z bridge arm 61, the writing end of the hard magnetic pole 30 facing the Z bridge arm 60, the support end 25 of the hard magnetic pole array 3 penetrating the second soft magnetic shielding layer 8 and located at the first surface layer 301, and the hard magnetic poles have magnetic moments in the +Z or -Z directions.

[0170] Example 3: Figure 3 The hard magnetic write head shown is a structure with structure one plus setting one and setting three. The structure includes: substrate 2 (2), second soft magnetic shielding layer 8, first intermediate metal layer 7, third soft magnetic shielding layer 10, second intermediate metal layer 9 and hard magnetic pole array 3.

[0171] The substrate 2(2) here is a PCB, which can be regarded as a double-layer board, including: a non-magnetic layer 2', a second soft magnetic shielding layer 8 and its first intermediate metal layer 7 located at the first surface layer 301 of the PCB, a third soft magnetic shielding layer 10 and its second intermediate metal layer 9 located at the second surface layer 302 of the PCB, and a hard magnetic pole array 3 embedded in the substrate PCB and penetrating the PCB, wherein the writing end 24 of the hard magnetic pole array 3 penetrates the third soft magnetic shielding layer 10 and is located on the second surface layer 302, and the third soft magnetic shielding layer 10 surrounds the hard magnetic pole array 3, with a gap of 11 between them. The writing end of the hard magnetic pole array 3 faces the Z-bridge arm array 6 on the wafer 5, such as the writing end of hard magnetic pole 33 facing the Z-bridge arm 63, the writing end of hard magnetic pole 32 facing the Z-bridge arm 62, the writing end of hard magnetic pole 31 facing the Z-bridge arm 61, and the writing end of hard magnetic pole 30 facing the Z-bridge arm 60. The support end 25 of the hard magnetic pole array 3 penetrates the second soft magnetic shielding layer 8 and is located on the first surface layer 301. The hard magnetic poles have magnetic moments in the +Z or -Z direction.

[0172] Specifically, Figure 4 for Figure 3 Structural bottom view, where section AA corresponds to Figure 3 The writing head 1(1) has hard magnetic poles 30-33 and 30(0)-33(0) located on the window of the third soft magnetic shielding layer 10, and each hard magnetic pole is surrounded by the third soft magnetic shielding layer 10, and a gap is formed between them.

[0173] Example 4: Figure 5The hard magnetic write head shown is a structure with structure one plus setting one, setting three and setting five. The structure includes: substrate 2 (3), hard magnetic pole array 3, second soft magnetic shielding layer 8, third soft magnetic shielding layer 10, first intermediate metal layer 7, second intermediate metal layer 9, third intermediate metal layer 12 and fourth soft magnetic shielding layer 13.

[0174] In this example, substrate 2(3) is a PCB, equivalent to a double-layer PCB. The second soft magnetic shielding layer 8 is located on the first surface layer 301 of the PCB, the third soft magnetic shielding layer 10 is located on the second surface layer 302 of the PCB, and the fourth soft magnetic shielding layer is located above the second surface layer 2(3) of the PCB. The third soft magnetic shielding layer 10, the third soft magnetic shielding layer 8, and the fourth soft magnetic shielding layer 13 are respectively transitioned by the first intermediate metal layer 7, the second intermediate metal layer 9, and the third intermediate metal layer 12. The hard magnetic pole array 3 is embedded in the substrate PCB and penetrates through the PCB. The writing end 24 of the hard magnetic pole array 3 penetrates through the third soft magnetic shielding layer 10 and forms an annular gap 11 with the third soft magnetic shielding layer 10. The supporting end 25 of the hard magnetic pole array 3 penetrates through the second soft magnetic shielding layer 8 and is located below the fourth soft magnetic shielding layer 13. The correspondence between the hard magnetic pole array 3 and the Z-bridge arm array on the wafer 5 of the Z-axis magnetoresistive sensor is as described above. Figure 1-3 The same applies, so I won't go into details here.

[0175] Optionally, the hard magnetic pole arrays in Examples 1 to 4 above can be prefabricated permanent magnets, i.e., pre-prepared permanent magnet strips or rods are directly mounted into the PCB vias. Alternatively, they can be thick-film permanent magnets, i.e., a thick film of permanent magnets prepared using a gas flow sputtering method is directly filled into the PCB vias. The specific structure of this hard magnetic pole array can be selected according to actual conditions, and this application does not impose specific limitations.

[0176] Example 5: Figure 6 The hard magnetic write head shown is another structure of structure one plus setting one, setting three and setting five. The structure includes: substrate 2 (4), hard magnetic pole array 3', second soft magnetic shielding layer 8, third soft magnetic shielding layer 10, first intermediate metal layer 7, second intermediate metal layer 9, third intermediate metal layer 12 and fourth soft magnetic shielding layer 13.

[0177] The substrate 2(4) here is a PCB, which is equivalent to a double-layer PCB. The second soft magnetic shielding layer 8 is located on the first surface layer 301 of the PCB, the third soft magnetic shielding layer 10 is located on the second surface layer 302 of the PCB, and the fourth soft magnetic shielding layer 13 is located above the second surface layer 302 of the PCB. The second soft magnetic shielding layer 8, the third soft magnetic shielding layer 10 and the fourth soft magnetic shielding layer 13 are respectively transitioned by the first intermediate metal layer 7, the second intermediate metal layer 9 and the third intermediate metal layer 12. The hard magnetic pole array 3' is embedded in the substrate PCB and penetrates through the PCB. The writing end 24 of the hard magnetic pole array 3' penetrates through the third soft magnetic shielding layer 10 and forms an annular gap 11 with the third soft magnetic shielding layer 10. The supporting end 25 of the hard magnetic pole array 3' penetrates through the second soft magnetic shielding layer 8 and is located below the fourth soft magnetic shielding layer 13. The correspondence between the hard magnetic pole array 3 and the Z-bridge arm array on the wafer 5 of the Z-axis magnetoresistive sensor is as described above. Figure 1-3 The same applies, so I won't go into details here.

[0178] The hard magnetic pole array 3' is a composite permanent magnet formed by filling PCB vias with a mixture of permanent magnet powder and colloidal material. This composite permanent magnet has a multi-step shape, assuming N steps, with a circular or square cross-section. The first step near the hard magnetic pole support end 25 has a cross-sectional dimension of D1, and the Nth step near the hard magnetic pole writing end 24 has a cross-sectional dimension of DN. Therefore, the cross-sectional dimensions of the N steps are in the order: D1 > D2… > DN. In this example, there are 3 steps. The first step near the hard magnetic pole support end 25 has the largest dimension, the third step near the hard magnetic pole writing end 24 has the smallest dimension, and the second step is in between.

[0179] Example 6: Figure 7 The hard magnetic writing head shown is a structure with structure two plus setting one and setting three. The structure includes: microwave coil array 14, PCB substrate 2 (5), hard magnetic pole array 3', second soft magnetic shielding layer 8, third soft magnetic shielding layer 10, first intermediate metal layer 7, second intermediate metal layer 9, third intermediate metal layer 12 and fourth soft magnetic shielding layer 13.

[0180] The PCB substrate 2 (5) here is equivalent to a double-layer PCB, wherein the second soft magnetic shielding layer 8 is located on the first surface layer 301 of the PCB, the third soft magnetic shielding layer 10 and the microwave coil array 14 are located on the second surface layer 302 of the PCB, and the fourth soft magnetic shielding layer 13 is located on the second soft magnetic shielding layer 8. The second soft magnetic shielding layer 8, the third soft magnetic shielding layer 10 and the fourth soft magnetic shielding layer 13 respectively use the first intermediate metal layer 7, the second intermediate metal layer 9 and the third intermediate metal layer 12 as transition layers.

[0181] Among them, such as Figure 8 As shown, Figure 8 for Figure 7Structural bottom view, where section BB corresponds to Figure 7 The writing head 1(1) and microwave coil array 14 include: microwave coils 14(1) and 14(2), each microwave coil surrounding at least one hard magnetic pole. In the example, microwave coil 14(1) surrounds four hard magnetic poles 32, 33, 32(0) and 33(0), and microwave coil 14(2) surrounds four hard magnetic poles 30, 31, 20(0) and 31(0). A third soft magnetic shielding layer 10 surrounds the hard magnetic poles 30-33, 30(0)-33(0) and forms a gap between them; and a gap is formed between each microwave coil 14(1) and 14(2) and the third shielding layer 10, with the remainder covered by the third shielding layer 10 as shown.

[0182] Example 7: Figure 9 The hard magnetic writing head shown is a structure of four plus setting one and setting three. The structure includes: PCB substrate 2 (6), hard magnetic pole array 3', microwave coil array 14, heating coil array 15, second soft magnetic shielding layer 8, third soft magnetic shielding layer 10, first intermediate metal layer 7, second intermediate metal layer 9, third intermediate metal layer 12 and fourth soft magnetic shielding layer 13.

[0183] Here, the PCB substrate 2 (6) is equivalent to a double-layer PCB. The second soft magnetic shielding layer 8 is located on the first surface layer 301 of the PCB, the third soft magnetic shielding layer 10, the microwave coil array 14 and the heating coil array 15 are located on the second surface layer 302 of the PCB, and the fourth soft magnetic shielding layer 13 is located on the second soft magnetic shielding layer 8. The second soft magnetic shielding layer 8, the third soft magnetic shielding layer 10 and the fourth soft magnetic shielding layer 13 respectively use the first intermediate metal layer 7, the second intermediate metal layer 9 and the third intermediate metal layer 12 as transition layers.

[0184] In this configuration, each hard magnetic pole is surrounded by a heating coil, while each microwave coil is surrounded by at least one hard magnetic pole. In the example, such as... Figure 10 As shown, Figure 10 for Figure 9 Structural bottom view, where section CC corresponds to Figure 9The writing head 1(1) is in the microwave coil 14(1) which surrounds four hard magnetic poles 32, 33, 32(0) and 33(0), heating coil 15(2) surrounds hard magnetic pole 32, heating coil 15(1) surrounds hard magnetic pole 33, heating coil 15'(2) surrounds hard magnetic pole 32(0), heating coil 15'(1) surrounds hard magnetic pole 33(0); microwave coil 14(2) surrounds four hard magnetic poles 30, 31, 30(0) and 31(0), heating coil 15(3) surrounds hard magnetic pole 31, heating coil 15(4) surrounds hard magnetic pole 30, heating coil 15'(3) surrounds hard magnetic pole 31(0), heating coil 15'(4) surrounds hard magnetic pole 30(0). Each microwave coil, such as 14(1) and 14(2), is separated from the third soft magnetic shielding layer 10 by a gap. Each heating coil, such as 15(1)-15(4) and 15'(1)-15'(4), is separated from the third soft magnetic shielding layer 10 by a gap. The remaining areas are covered by the third soft magnetic shielding layer 10.

[0185] Example 8: Figure 11 The hard magnetic writing head shown is a structure of structure four plus setting two and setting four. The structure includes: wafer substrate 2 (7), hard magnetic pole array 3 (00), second soft magnetic shielding layer 8 (1), third soft magnetic shielding layer 10 (1), microwave coil array 14 (0) and heating coil array 15 (0).

[0186] The wafer substrate 2(7) here can be silicon, or a non-silicon substrate, such as glass, polymer, etc. The specific material of the wafer substrate 2(7) can be selected according to the actual situation, and this application does not impose specific restrictions.

[0187] The aforementioned hard magnetic pole array 3 (00) is located above the wafer substrate 2 (7) and is a thick film permanent magnet deposited by gas flow sputtering. The second soft magnetic shielding layer 8 (1) is located between the wafer substrate 2 (7) and the support end 25 of the hard magnetic pole array 3 (00).

[0188] Each hard magnetic pole writing end is surrounded by a heating coil and a third soft magnetic shielding layer. The heating coil is located between the third soft magnetic shielding layer and the hard magnetic pole. There are gaps between the heating coil and the hard magnetic pole, and between the heating coil and the third soft magnetic shielding layer. For example, hard magnetic poles 30 (00), 31 (00), 32 (00) or 33 (00) are all surrounded by heating coils 15 (04), 15 (03), 15 (02) or 15 (01) respectively, and there is a gap between the hard magnetic poles and the heating coils. Then, the hard magnetic poles 30 (00) and heating coils 15 (04), 31 (00) and heating coils 15 (03), 15 (02) and heating coils 15 (02), and 15 (01) and heating coils 15 (01) are all surrounded by a third soft magnetic shielding layer 10 (1), and there is a gap between the third soft magnetic shielding layer and the heating coils. Microwave coils 14 (01) or 14 (02) surround at least one hard magnetic pole and its corresponding heating coil.

[0189] In this embodiment, a bottom view of the write head 1 (6) can be referenced. Figure 10 Microwave coil 14(01) surrounds four hard magnetic poles and a heating coil, including Figure 11 Two visible elements are 32(00) and 33(00), and two corresponding visible heating coils 15(02) and 15(01). Microwave coil 14(02) surrounds four hard magnetic poles and the heating coils, including... Figure 11 Two visible 30(00) and 31(00) are visible, as are two corresponding visible heating coils 15(04) and 15(03). There is a gap between microwave coils 14(01) and 14(02) and the third soft magnetic shielding layer 10(1), and the remaining positions are covered by the third soft magnetic shielding layer 10(1). In addition, there is a fourth intermediate metal layer 7(1) between the second soft magnetic shielding layer 8(1) and the wafer 2(7), a fifth intermediate metal layer 3(01) at the support end of the hard magnetic pole 3(00), a sixth intermediate metal layer 9(1) between the third soft magnetic shielding layer 10(1), the microwave coil array 14(0), and the heating coil array 15(0), and the hard magnetic pole array 3(00) is filled and insulated with polyimide 111. 8(2) is a wet etching stop layer when the thick film permanent magnet is processed into a hard magnetic pole.

[0190] It should be understood that the above are only examples of partial hard magnetic write head structures, and do not list all possible combinations of this hard magnetic write head structure. In actual manufacturing, for PCB substrates, a prefabricated permanent magnet hard magnetic pole array can be selected, which may include all or part of a second soft magnetic shielding layer, a third soft magnetic shielding layer, a fourth soft magnetic shielding layer, a microwave coil, and a heating coil. For PCB substrates, a composite permanent magnet array can also be selected, which may also include all or part of a second soft magnetic shielding layer, a third soft magnetic shielding layer, a fourth soft magnetic shielding layer, a microwave coil, and a heating coil. For wafer substrates, only a thick-film permanent magnet hard magnetic pole array can be selected, which may also include all or part of a second soft magnetic shielding layer, a third soft magnetic shielding layer, a microwave coil, and a heating coil.

[0191] In the above arrangement of hard magnetic writing head structures, the fourth soft magnetic shielding layer can only be prepared when the third soft magnetic shielding layer is already in place.

[0192] To facilitate understanding of this embodiment, the hard magnetic write head device disclosed in this application embodiment will be described in detail below. This hard magnetic write head device includes the aforementioned hard magnetic write head and a first soft magnetic shielding layer.

[0193] The write head is located above the wafer of the Z-axis magnetoresistive sensor, and the first soft magnetic shielding layer is located below the wafer of the Z-axis magnetoresistive sensor.

[0194] Furthermore, the hard magnetic write data system containing the hard magnetic write head disclosed in the embodiments of this application will be described in detail below. This hard magnetic write data system includes the aforementioned hard magnetic write head device and a probe test station.

[0195] During the data writing process, both the wafer of the Z-axis magnetoresistive sensor and the hard magnetic writing head are placed on the probe test stage. The wafer of the Z-axis magnetoresistive sensor is placed on the XY wafer stage of the probe test stage, and the hard magnetic writing head is placed on the probe holder of the probe test stage. The first soft magnetic shield is located between the wafer of the Z-axis magnetoresistive sensor and the XY wafer stage, and the first soft magnetic shield can be located on the back of the wafer of the Z-axis magnetoresistive sensor or on the XY wafer stage.

[0196] The positioning and alignment of the cell writing areas of the hard magnetic writing head and the Z-axis magnetoresistive sensor wafer in the XY direction, as well as the control of the writing spacing in the Z direction, are achieved by operating the probe test stage. The writing spacing between the hard magnetic writing head and the Z-axis magnetoresistive sensor wafer is controlled within the working spacing.

[0197] The hard magnetic write head is positioned and written sequentially in different cell writing areas on the wafer of the Z-axis magnetoresistive sensor by manipulating the probe mount.

[0198] The cell writing area here refers to a single die, a mask exposure area, or the entire wafer on the wafer of the Z-axis magnetoresistive sensor.

[0199] In some embodiments, the system further includes an auxiliary heating device. This auxiliary heating device is disposed on the wafer of the Z-axis magnetoresistive sensor or on a probe test stage.

[0200] The manufacturing method of the write head disclosed in the embodiments of this application will be described in detail below.

[0201] As can be understood from the above embodiments, the hard magnetic write head can include various different structures, and different structures of hard magnetic write heads can correspond to different manufacturing methods. Of course, hard magnetic write heads with the same structure can also correspond to different manufacturing methods. The manufacturing method of the hard magnetic write head can be adjusted according to the specific structure of the hard magnetic write head and different processing technologies. For example, the hard magnetic write head can include a PCB substrate or a wafer substrate, and the PCB substrate and the wafer substrate can be manufactured using different methods. Of course, the processing methods corresponding to the same PCB may also be different; for example, the PCB processing technology can include different process types such as machining and typical PCB processing technologies. The processing technology of the hard magnetic write head can be adjusted according to the actual situation.

[0202] The following illustrations demonstrate the manufacturing process of some hard magnetic write heads. This process includes, but is not limited to, the following methods:

[0203] Method 1: The processing technology of Method 1 is used for hard magnetic write heads with prefabricated permanent magnets mounted in the first PCB through-hole of a PCB. This method includes: 1) Selecting a double-layer PCB, where the first and second surface layers correspond to the second and third soft magnetic shielding layers, respectively, with both layers using a non-magnetic intermediate metal layer as a transition layer; 2) Fabricating a heating coil, microwave coil, and hard magnetic pole window on the third soft magnetic shielding layer using PCB processing technology, while retaining the third soft magnetic shielding layers between them; 3) Processing a first PCB through-hole with a diameter of d, penetrating the double-layer PCB and the hard magnetic pole window; 4) Placing a non-magnetic alignment plate to close the first through-hole, while simultaneously mounting the prefabricated permanent magnets in the first PCB through-hole, ensuring that all prefabricated permanent magnet write ends are aligned with the non-magnetic alignment plate; 5) Removing the non-magnetic alignment plate to obtain a hard magnetic pole array; 6) Depositing a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, with a non-magnetic metal intermediate layer transitioning between the second and fourth soft magnetic shielding layers.

[0204] The PCB processing technologies here include photolithography, development, wet etching, and electroplating.

[0205] Specifically, such as Figure 12 As shown, this method can be implemented through the following specific steps:

[0206] a) The initial substrate is PCB300, which is a double-layer PCB structure, including: a non-magnetic insulating portion 2, a second soft magnetic shielding layer 8 located at the first surface layer 301, and a third soft magnetic shielding layer 10 located at the second surface layer 302. The second soft magnetic shielding layer 8 and the third soft magnetic shielding layer 10 are respectively transitioned by intermediate metal layers 7 and 9. Here, a1 is a front view of PCB300, and a2 is a top view of the second surface layer 302, which is entirely covered by the third soft magnetic shielding layer 10.

[0207] b) Using typical PCB processing techniques, including: processing the following on the third soft magnetic shielding layer 10 corresponding to the second surface layer 302 of PCB 300: a hard magnetic pole window 80', which is a circular area, wherein the excess third soft magnetic shielding layer 10 is removed, as shown in Figure b2; a heating coil 15', a first arc gap 81' separating the heating coil 15' and the third soft magnetic shielding layer 10, the heating coil 15' being a circular area, and the first arc gap 81' being an annular area; a microwave coil 14', a second arc gap 82' and a third arc gap 83' separating the microwave coil 14' and the third soft magnetic shielding layer 10, the microwave coil 14', the second arc gap 82' and the third arc gap 83' being circular areas. Here, b1 is the front view after processing in step b), and b2 is the top view of the corresponding second surface layer 302.

[0208] c) A first through-hole 16' is fabricated on PCB300, such that the through-hole is located at the center of the hard magnetic pole window 80'. Wherein, c1 is the front view after step c) and c2 is the top view of the corresponding second surface layer 302.

[0209] d) Place a non-magnetic alignment plate 18 on the second surface layer 302 of PCB 300, and then install a prefabricated hard magnetic pole 3 from a first surface layer 301 into the first through hole 16', so that the writing end of the hard magnetic pole 3 is aligned with the surface of the non-magnetic alignment plate 18. Wherein, d is the front view after step d).

[0210] e) Remove the non-magnetic alignment plate 18. Wherein, e is the front view after step e).

[0211] f) A fourth soft magnetic shielding layer 13 is deposited on the surface of the first surface layer 301 of PCB 300, and a third metal intermediate layer 12 is used for transition. Wherein, f is a front view after the processing in step f).

[0212] Method 2: The processing technology of Method 2 is used for: a hard magnetic write head of a prefabricated permanent magnet mounted in a first PCB through-hole on a PCB substrate. The method includes: 1) selecting a double-layer PCB, with a second soft magnetic shielding layer and a third soft magnetic shielding layer respectively provided on the first and second surface layers of the PCB, both of which use a non-magnetic intermediate metal layer as a transition layer; 2) processing a first through-hole with a diameter of d, penetrating the double-layer PCB; 3) processing a stepped countersunk hole with a size of D (D>d), the stepped countersunk hole and the first through-hole being coaxial; processing a first arc groove, a second arc groove and a third arc groove, the first arc groove and the stepped countersunk hole being... The third soft magnetic shielding layer between the second and third arc grooves is a heating coil; the third soft magnetic shielding layer between the second and third arc grooves is a microwave coil. The stepped countersunk hole, the first arc groove, the second arc groove, and the third arc groove all penetrate the third soft magnetic shielding layer and extend into the PCB insulation layer; 4) Place a non-magnetic alignment plate to seal the stepped countersunk hole, and at the same time install the prefabricated permanent magnet in the first PCB through hole so that the writing end of the prefabricated permanent magnet is aligned with the non-magnetic alignment plate; 5) Remove the non-magnetic alignment plate to obtain a hard magnetic pole array; 6) Deposit a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, and use a non-magnetic metal interlayer to transition between the second and fourth soft magnetic shielding layers.

[0213] Specifically, such as Figure 13 As shown, this method can be implemented through the following specific steps:

[0214] a) The initial substrate is PCB300, which is a double-layer PCB structure, including: a non-magnetic insulating portion 2, a second soft magnetic shielding layer 8 located at the first surface layer 301, and a third soft magnetic shielding layer 10 located at the second surface layer 302. The second soft magnetic shielding layer 8 and the third soft magnetic shielding layer 10 are respectively transitioned by intermediate metal layers 7 and 9. Here, a1 is a front view of PCB300, and a2 is a top view of the second surface layer 302, which is entirely covered by the third soft magnetic shielding layer 10.

[0215] b) A first through hole 16 is processed on PCB300. At this time, a hole 16 appears on the third soft magnetic shielding layer 10. Figure b1 is a front view of PCB300 after step b) and Figure b2 is a top view of the second surface layer 302.

[0216] c) Using mechanical processing, the third soft magnetic shielding layer 10, where the second surface layer 302 of PCB 300 is located, is processed as follows: a stepped countersunk hole 80, in which the third soft magnetic shielding layer 10 is not present, and extending into the non-magnetic insulating layer 2; the stepped countersunk hole 80 and the first through hole 16 are coaxial; a first arc groove 81, a second arc groove 82, and a third arc groove 83 are formed, wherein the heating coil 15 is located between the first arc groove 81 and the stepped countersunk hole 80, and the microwave coil 14 is located between the second arc groove 82 and the third arc groove 83. Figure c1 is a front view of PCB 300 after step c) processing, and Figure c2 is a top view of the second surface layer 302.

[0217] d) Place a non-magnetic alignment plate 18 on the second surface layer 302 of PCB 300, and then install a prefabricated hard magnetic pole 3 from a first surface layer 301 into the first through hole 16, so that the writing end of the hard magnetic pole 3 is aligned with the surface of the non-magnetic alignment plate 18. Wherein, d is the front view after step d).

[0218] e) Remove the non-magnetic alignment plate 18. Wherein, e is the front view after step e).

[0219] f) A fourth soft magnetic shielding layer 13 is deposited on the surface of the first surface layer 301 of PCB 300, and a third metal intermediate layer 12 is used for transition. Wherein, f is a front view after the processing in step f).

[0220] Method 3: The processing technology of Method 3 is used for: hard magnetic write heads formed by filling a composite permanent magnet in a second PCB via of a PCB substrate with a mixture of permanent magnet powder and colloid. The method includes: 1) Selecting a double-layer PCB, with a second soft magnetic shielding layer and a third soft magnetic shielding layer respectively set on the first and second surfaces of the PCB, both of which use a non-magnetic intermediate metal layer as a transition layer; 2) Using cutters of different diameters, processing the second PCB via from the first surface to the second surface; 3) Using a non-magnetic transparent alignment plate to seal the stepped opening of the second PCB via located on the second surface, and placing an alignment permanent magnet on the other side of the non-magnetic transparent alignment plate so that the composite permanent magnet has a +Z or -Z polarity; 4) Mixing 5) A mixture of permanent magnet powder and colloid is formed and dispersed on the first surface layer. The mixture is filled into the second PCB through hole, and excess magnetic powder is removed; 6) The non-magnetic transparent alignment plate is removed; 7) A stepped countersunk hole with a size of D (D>d) is processed, and the stepped countersunk hole and the second through hole are coaxial; A first circular arc groove, a second circular arc groove and a third circular arc groove are processed. The third soft magnetic shielding layer between the first circular arc groove and the stepped countersunk hole is a heating coil; The third soft magnetic shielding layer between the second circular arc groove and the third circular arc groove is a microwave coil. The stepped countersunk hole, the first circular arc groove, the second circular arc groove and the third circular arc groove all penetrate the third soft magnetic shielding layer and penetrate into the PCB insulation layer; 8) A fourth soft magnetic shielding layer is deposited on the second soft magnetic shielding layer. A non-magnetic metal interlayer is used for transition between the second soft magnetic shielding layer and the fourth soft magnetic shielding layer.

[0221] Specifically, such as Figure 14 As shown, this method can be implemented through the following specific steps:

[0222] a) The initial substrate is PCB300, which is a double-layer PCB structure, including: a non-magnetic insulating portion 2, a second soft magnetic shielding layer 8 located at the first surface layer 301, and a third soft magnetic shielding layer 10 located at the second surface layer 302. The second soft magnetic shielding layer 8 and the third soft magnetic shielding layer 10 are respectively transitioned by intermediate metal layers 7 and 9. Wherein a1 is a front view of PCB300, and a2 is a top view of the second surface layer 302, which is entirely covered by the third soft magnetic shielding layer 10.

[0223] b) Machining multi-stage stepped through holes, i.e., the second through hole 16”. Here, b is the front view of PCB300 in step b).

[0224] c) A transparent non-magnetic alignment plate 18' is placed on the second surface layer 302 of PCB 300, and then a permanent magnet 19 is placed there, with the transparent non-magnetic alignment plate 18' located between the permanent magnet 19 and PCB 2; then, powder 20, which is a uniform mixture of permanent magnet powder and colloid, is filled into the first surface layer 301, and then extruded into the second through hole 16” using a plastic scraper 21 and compacted to form a composite permanent magnet. The permanent magnet 19 achieves Z-axis orientation by the magnetic moment of the magnetic powder during the curing process of the composite permanent magnet. Wherein, c is the front view of PCB 300 in step c).

[0225] d) Scrape off excess powder and remove permanent magnet 19 and transparent non-magnetic alignment plate 18'. Wherein, d is the front view of PCB300 in step d).

[0226] e) Using mechanical processing, the third soft magnetic shielding layer 10, where the second surface layer 302 of PCB300 is located, is processed as follows: a permanent magnet window 80 (1) is formed, excess third soft magnetic shielding layer 10 is removed, and it extends into the insulating layer 2; the permanent magnet window 80 (1) is coaxial with the second through hole 16”; a first arc groove 81 (1), a second arc groove 82 (1), and a third arc groove 83 (1) are formed, wherein the heating coil 15 (1) is located between the first arc groove 81 (1) and the permanent magnet window 80 (1), and the microwave coil 14 (1) is located between the second arc groove 82 (1) and the third arc groove 83 (1). Here, e is the front view of PCB300 in step e).

[0227] f) A fourth soft magnetic shielding layer 13 is deposited on the surface of the first surface layer 301 of PCB 300, and a third metal intermediate layer 12 is used for transition. Wherein, f is a front view of PCB 300 in step f).

[0228] Method 4: The processing technology of Method 4 is used for: hard magnetic write heads formed by a composite permanent magnet consisting of a mixture of permanent magnet powder and colloid filled in a second PCB through-hole in a PCB substrate. The method includes: 1) Selecting a double-layer PCB, with a second soft magnetic shielding layer and a third soft magnetic shielding layer respectively set on the first and second surfaces of the PCB, both of which use a non-magnetic intermediate metal layer as a transition layer; 2) Using cutters of different diameters, processing the second PCB through-hole from the first surface to the second surface; 3) Using a non-magnetic transparent alignment plate to seal the stepped opening of the second PCB through-hole located on the second surface, and in the non-magnetic... 4) Place the alignment permanent magnet on the other side of the transparent alignment plate so that the composite permanent magnet has +Z or -Z polarity; 5) Mix permanent magnet powder and colloid to form a mixture and disperse it on the first surface layer. Fill the mixture into the second PCB through hole and remove excess magnetic powder; 6) Remove the non-magnetic transparent alignment plate; 7) Use PCB processing technology to prepare the heating coil, microwave coil, and hard magnetic pole window on the third soft magnetic shielding layer, and retain the third soft magnetic shielding layer between them; 8) Deposit the fourth soft magnetic shielding layer on the second soft magnetic shielding layer, and use a non-magnetic metal interlayer to transition between the second soft magnetic shielding layer and the fourth soft magnetic shielding layer.

[0229] Specifically, such as Figure 15 As shown, this method can be implemented through the following specific steps:

[0230] a) The initial substrate is PCB300, which is a double-layer PCB structure, including: a non-magnetic insulating portion 2, a second soft magnetic shielding layer 8 located at the first surface layer 301, and a third soft magnetic shielding layer 10 located at the second surface layer 302. The second soft magnetic shielding layer 8 and the third soft magnetic shielding layer 10 are respectively transitioned by intermediate metal layers 7 and 9. Wherein a1 is a front view of PCB300, and a2 is a top view of the second surface layer 302, which is entirely covered by the third soft magnetic shielding layer 10.

[0231] b) Machining multi-stage stepped through holes, i.e., the second through hole 16”. Here, b is the front view of PCB300 in step b).

[0232] c) A transparent non-magnetic alignment plate 18' is placed on the second surface layer 302 of PCB 300, and then a permanent magnet 19 is placed there, with the transparent non-magnetic alignment plate 18' located between the permanent magnet 19 and PCB 2; then, powder 20, which is a uniform mixture of permanent magnet powder and colloid, is filled into the first surface layer 301, and then extruded into the stepped through hole 16” using a plastic scraper 21 and compacted to form a composite permanent magnet. The permanent magnet 19 achieves Z-axis orientation by the magnetic moment of the magnetic powder during the curing process of the composite permanent magnet. Wherein, c is the front view of PCB 300 in step c).

[0233] d) Scrape off excess powder and remove permanent magnet 19 and transparent non-magnetic alignment plate 18'. Wherein, d is the front view of PCB300 in step d).

[0234] e) Using typical PCB processing techniques, including photolithography, development, wet etching, and electroplating, the following are processed on the third soft magnetic shielding layer 10 corresponding to the second surface layer 302 of the PCB 300: a hard magnetic pole window 80(3), which is a circular area, in which excess third soft magnetic shielding layer 10 is removed; a heating coil 15(3), a first arc gap 81(3), separating the heating coil 15(3) and the third soft magnetic shielding layer 10, the heating coil 15(3) being a circular area, the first arc gap 81(3) being an annular area; a microwave coil 14(2), a second arc gap 82(3), and a third arc gap 83(3), separating the microwave coil 14(2) and the third soft magnetic shielding layer 10, the microwave coil 14(2), the second arc gap 82(3), and the third arc gap 83(3) being circular areas. Here, e is a front view of the PCB 300 in step e).

[0235] f) A fourth soft magnetic shielding layer 13 is deposited on the surface of the first surface layer 301 of PCB 300, and a third metal intermediate layer 12 is used for transition. Wherein, f is a front view of PCB 300 in step f).

[0236] In some embodiments, the aforementioned hard magnetic poles may also be thick-film permanent magnets deposited by gas flow sputtering.

[0237] like Figure 16 As shown, Figure 16 This diagram illustrates the principle of soft magnetic thick film deposition using a gas flow sputtering method. During deposition, Ar gas passes through the target 100, which serves as the hollow cathode, and the grounded vacuum chamber shell 101 acts as the anode, generating a glow discharge and plasma 99. The target, acting as the cathode, is sputtered onto the substrate 102 by the plasma. SmCo or other hard magnetic alloys can be selected. The gas flow sputtering method features a high deposition rate, reaching 50 μm·h⁻¹, and can be used to fabricate thick-film hard or soft magnetic materials.

[0238] like Figure 17 As shown, Figure 17 This diagram illustrates a gas flow sputtering deposition apparatus for thick films. The apparatus includes a soft or hard magnetic target 100, a cooling inlet 104, and a frame structure 103. The soft or hard magnetic target 100 is mounted inside the frame structure 103, the cooling inlet 104 is located on the frame structure 103, and air (Ar) passes through the hollow space formed by the target.

[0239] In one embodiment, such as Figure 18 As shown, Figure 18A schematic diagram of a hard magnetic thick film deposited on a PCB by airflow sputtering to fill the first through hole. PCB2 (20) is placed on substrate 102. Before depositing the hard magnetic thick film, a fourth metal intermediate layer 3 (0) is deposited on the hole wall, and then a permanent magnet thick film 3 is deposited to fill the first through hole.

[0240] In another embodiment, such as Figure 19 As shown, Figure 19 This is a schematic diagram of the deposition of a hard magnetic thick film on a wafer by gas flow sputtering. The wafer 105 is placed on the substrate 102, and a fifth intermediate metal layer 105(0) is pre-deposited on the wafer before the deposition of the thick film 106 to improve the adhesion between the hard magnetic thick film 106 and the wafer 105.

[0241] It should be understood that when the hard magnetic pole is obtained by depositing a soft magnetic thick film using a gas flow sputtering method, the hard magnetic write head can also be manufactured in different ways, for example:

[0242] Method 5: The processing technology of Method 5 is used for hard magnetic write heads where thick-film permanent magnets are deposited in through-holes in a wafer substrate using a gas flow sputtering method. This method includes: 1) depositing a second soft magnetic shielding layer on the wafer using a gas flow sputtering method, with a non-magnetic metal interlayer transitioning between the second soft magnetic shielding layer and the wafer; 2) depositing a wet etching stop layer for the permanent magnet thick-film hard magnetic poles: a SiO2, Si3N4, or Al2O3 thin film; 3) depositing the thick-film permanent magnet using a gas flow sputtering method. ; 4) Use photoresist as a mask to form the etching window of the hard magnetic pole of the thick film permanent magnet; 5) Wet etching of the thick film permanent magnet and removal of photoresist to obtain the hard magnetic pole array of the thick film permanent magnet; 6) Spin polyimide to fill the gaps and surface of the hard magnetic pole array of the thick film permanent magnet, solidify and flatten it; 7) Reactive ion etching (RIE) to thin the polyimide; 8) Sputter seed layer; 9) Electroplating heating coil, microwave coil and third soft magnetic shielding layer; 10) Remove seed layer to obtain the write head.

[0243] Specifically, such as Figure 20 As shown, this method can be implemented through the following specific steps:

[0244] a) A fifth intermediate metal layer 105(0) and a second soft magnetic shielding layer 106 are deposited on wafer 105; wherein, a is a front view of wafer 105 in step a).

[0245] b) A wet etching stop layer, such as a Si3N4, Al2O3, or SiO2 ceramic material thin film 107, is deposited to cover a second soft magnetic shielding layer 106; wherein b is a front view of the wafer 105 in step b).

[0246] c) Deposit a non-magnetic sixth intermediate metal layer 108(0) and deposit a hard magnetic thick film 108 by gas flow sputtering; wherein c is a front view of the wafer 105 in step c).

[0247] d) Photoresist is used as a mask 109 to form a thick film etching window; where d is a front view of wafer 105 in step d).

[0248] e) Wet etching of hard magnetic thick film 108 to remove excess hard magnetic thick film 110 between hard magnetic poles to form hard magnetic pole array 3 (00); where e is a front view of wafer 105 in step e).

[0249] f) Spin polyimide 111, cure, and planarize it so that the hard magnetic poles are covered in the polyimide; where f is a front view of wafer 105 in step f).

[0250] g) Reactive ion etching (RIE) thinning of polyimide; where g is a front view of wafer 105 in step g).

[0251] h) Deposit seed layer 112; where h is a front view of wafer 105 in step h).

[0252] i) Using photoresist as a mask, process the third soft magnetic shielding layer 113, the heating coil 114 and the microwave coil 115 respectively; where i is the front view of the wafer 105 in step i).

[0253] j) Remove the seed layer to obtain the write head. Here, j is the front view of wafer 105 in step j).

[0254] Method Six: The processing technology of Method Six is ​​used for: a hard magnetic write head with a thick-film permanent magnet deposited in a first PCB via of a PCB substrate using a gas flow sputtering method. This method includes: 1) selecting a double-layer PCB, with a second soft magnetic shielding layer and a third soft magnetic shielding layer respectively set on the first and second surfaces of the PCB, both using a non-magnetic intermediate metal layer as a transition layer; 2) using PCB processing technology to fabricate a heating coil, a microwave coil, and a hard magnetic pole window on the third soft magnetic shielding layer, while retaining the third soft magnetic pole window between them. 3) Spray photoresist as a sacrificial layer to cover the second surface layer of the PCB; 4) Process the first PCB via with a diameter of d, penetrating the PCB and the photoresist layer, and coaxial with the stepped countersunk hole; 5) Place the double-layer PCB on the substrate, align the end of the stepped countersunk hole with the target of the gas flow sputtering thick film deposition equipment, and begin to deposit a hard magnetic thick film until the via is filled; 6) Remove the photoresist to obtain a write head containing a hard magnetic thick film and hard magnetic poles; 7) Deposit a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, with a non-magnetic metal interlayer transitioning between the second and fourth soft magnetic shielding layers.

[0255] Specifically, such as Figure 21 As shown, this method can be implemented through the following specific steps:

[0256] a) The initial substrate is PCB300, which is a double-layer PCB structure, including: a non-magnetic insulating portion 2, a second soft magnetic shielding layer 8 located at the first surface layer 301, and a third soft magnetic shielding layer 10 located at the second surface layer 302. The second soft magnetic shielding layer 8 and the third soft magnetic shielding layer 10 are respectively transitioned by intermediate metal layers 7 and 9. The second surface layer 302 is entirely covered by the third soft magnetic shielding layer 10. Wherein a is a front view of PCB300 in step a).

[0257] b) Using typical PCB fabrication techniques, including: fabricating the following on the third soft magnetic shielding layer 10 corresponding to the second surface layer 302 of PCB 300: a hard magnetic pole window 80”, which is a circular area, in which excess third soft magnetic shielding layer 10 is removed, as shown in Figure b; a heating coil 15”, with a first arc gap 81” separating the heating coil 15” and the third soft magnetic shielding layer 10, the heating coil 15” being a circular area, and the first arc gap 81” being an annular area; a microwave coil 14”, with a second arc gap 82” and a third arc gap 83” separating the microwave coil 14” and the third soft magnetic shielding layer 10, the microwave coil 14”, the second arc gap 82” and the third arc gap 83” being circular areas. Here, b is a front view of PCB 300 in step b).

[0258] c) Photoresist 210 is used as a sacrificial layer to cover the second surface layer 302; where c is a front view of PCB 300 in step c).

[0259] d) The first through hole 16” is machined using a cutting tool so that the hard magnetic pole window 80” and the first through hole 16” are coaxial; where d is the front view of PCB300 in step d).

[0260] e) A thick film of hard magnetic pole 3 (01) is deposited by gas flow sputtering to fill the first through hole 16”, and a fourth metal intermediate layer 3 (00) is used to cover the bottom surface of the hole wall of the first through hole 16”; where e is the front view of PCB300 in step e).

[0261] f) Remove the photoresist to obtain hard magnetic pole 3”; where f is the front view of PCB300 in step f).

[0262] g) A fourth soft magnetic shielding layer 13 is deposited on the surface of the first surface layer 301 of PCB 300, and a third metal intermediate layer 12 is used for transition. Wherein, g is a front view of PCB 300 in step g).

[0263] Method 7: The processing technology of Method 7 is used for: a hard magnetic write head with a thick-film permanent magnet deposited in a first PCB via of a PCB substrate by gas flow sputtering. The method includes: 1) selecting a double-layer PCB, with a second soft magnetic shielding layer and a third soft magnetic shielding layer respectively set on the first and second surface layers of the PCB, both of which use a non-magnetic intermediate metal layer as a transition layer; 2) processing a stepped countersunk hole with a size of D (D>d), the stepped countersunk hole and the first via coaxial; processing a first arc groove, a second arc groove and a third arc groove, the third soft magnetic shielding layer between the first arc groove and the stepped countersunk hole being a heating coil; the third soft magnetic shielding layer between the second arc groove and the third arc groove... The first layer is a microwave coil. The stepped countersunk hole, the first arc groove, the second arc groove, and the third arc groove all penetrate the third soft magnetic shielding layer and extend into the PCB insulating layer; 3) Photoresist is used as a sacrificial layer to cover the second surface layer of the PCB; 4) The first PCB through hole with a diameter of d is processed, which penetrates the PCB and the photoresist layer and is coaxial with the stepped countersunk hole; 5) The double-layer PCB is placed on the substrate, and the end of the stepped countersunk hole is aligned with the target of the gas flow sputtering thick film deposition equipment to begin depositing a hard magnetic thick film until the through hole is filled; 6) The photoresist is removed to obtain a write head containing a hard magnetic thick film and hard magnetic poles; 7) A fourth soft magnetic shielding layer is deposited on the second soft magnetic shielding layer, and a non-magnetic metal interlayer is used to transition between the second soft magnetic shielding layer and the fourth soft magnetic shielding layer.

[0264] Specifically, such as Figure 22 As shown, this method can be implemented through the following specific steps:

[0265] a) The initial substrate is PCB300, which is a double-layer PCB structure, including: a non-magnetic insulating portion 2, a second soft magnetic shielding layer 8 located at the first surface layer 301, and a third soft magnetic shielding layer 10 located at the second surface layer 302. The second soft magnetic shielding layer 8 and the third soft magnetic shielding layer 10 are respectively transitioned by intermediate metal layers 7 and 9. The second surface layer 302 is entirely covered by the third soft magnetic shielding layer 10. Here, a is a front view of PCB300.

[0266] b) Using mechanical processing, the third soft magnetic shielding layer 10, where the second surface layer 302 of PCB300 is located, is processed as follows: a stepped countersunk hole 80”', in which there is no third soft magnetic shielding layer 10 and it extends into the non-magnetic insulating layer 2; a first arc groove 81”', a second arc groove 82”', and a third arc groove 83”', wherein the heating coil 15”' is located between the first arc groove 81”' and the stepped countersunk hole 80”', and the microwave coil 14”' is located between the second arc groove 82”' and the third arc groove 83”'. Here, b is the front view of PCB300 in step b)

[0267] c) Use photoresist 210”' as a sacrificial layer to cover the second surface layer 302; where c is the front view of PCB300 in step c).

[0268] d) The first through hole 16”' is machined using a cutting tool so that the stepped countersunk hole 80”' and the first through hole 16”' are coaxial; where d is the front view of PCB300 in step d).

[0269] e) A thick film of hard magnetic pole 3 (03) is deposited by gas flow sputtering to fill the first through hole 16”', and the bottom surface of the hole wall of the first through hole 16”' is covered by a fourth metal intermediate layer 3 (02); where e is the front view of PCB300 in step 3).

[0270] f) Remove the photoresist to obtain hard magnetic pole 3”'; where f is the front view of PCB300 in step f).

[0271] g) A fourth soft magnetic shielding layer 13 is deposited on the surface of the first surface layer 301 of PCB 300, and a third metal intermediate layer 12 is used for transition. Wherein, g is a front view of PCB 300 in step g).

[0272] In the example above, Figure 12 and Figure 13 The document outlines the fabrication process for a write head substrate consisting of a PCB, a hard magnetic pole array made of prefabricated permanent magnets, and including a second soft magnetic shielding layer, a third soft magnetic shielding layer, a fourth soft magnetic shielding layer, a microwave coil, and a heating coil.

[0273] Figure 14 and Figure 15 The document outlines the fabrication process for a write head substrate made of a PCB, a hard magnetic pole array made of a composite permanent magnet, and including a second soft magnetic shielding layer, a third soft magnetic shielding layer, a fourth soft magnetic shielding layer, a microwave coil, and a heating coil.

[0274] Figure 20 The fabrication process involves using a wafer as the substrate for the writing head, a thick-film permanent magnet as the hard magnetic pole array, and including the fabrication of a second soft magnetic shielding layer, a third soft magnetic shielding layer, a fourth soft magnetic shielding layer, a microwave coil, and a heating coil.

[0275] Figure 21 and Figure 22 The process involves fabricating a PCB substrate for the writing head, a thick-film permanent magnet array for the hard magnetic pole array, and including the fabrication process for the entire structure of the second soft magnetic shielding layer, the third soft magnetic shielding layer, the fourth soft magnetic shielding layer, the microwave coil, and the heating coil.

[0276] Optionally, the constituent material of the aforementioned permanent magnet is Alnico; or ferrite ceramic material MO·6Fe2O3, where M is Ba, Sr, or a combination of both; or selected from RECo5, where RE = Sm and / or Pr; RE2TM17, where RE = Sm, TM = Fe, Cu, Co, Zr, and / or Hf; and RE2TM14B, where RE = Nd, Pr, and / or Dy, TM = Fe and / or Co; or one or more of FeCrCo alloy and NbFeB alloy. The material of this permanent magnet can be selected according to the actual situation, and this application does not impose specific limitations.

[0277] The aforementioned first soft magnetic shielding layer is an alloy material, including at least one element selected from Co, Fe, and Ni, or at least one element selected from B, C, Si, transition elements, and rare earth elements. The material of the first soft magnetic shielding layer can be selected according to the actual situation, and this application does not impose specific restrictions.

[0278] It should be understood that the above is only an example of the fabrication process for a portion of the hard magnetic write head structure, and does not list the fabrication processes for all structures of the hard magnetic write head. In practice, for the PCB substrate, prefabricated permanent magnets or thick-film permanent magnets can be selected as the hard magnetic pole array, and the corresponding hard magnetic write head can be selected to include all or part of a second soft magnetic shielding layer, a third soft magnetic shielding layer, a fourth soft magnetic shielding layer, a microwave coil, and a heating coil. Among these, the fourth soft magnetic shielding layer can only be fabricated if the third soft magnetic shielding layer is already in place.

[0279] Similarly, for wafer substrates, only thick-film permanent magnet hard magnetic pole arrays can be selected for wafer substrates, and the corresponding hard magnetic writing head can be selected to include all or part of a second soft magnetic shielding layer, a third soft magnetic shielding layer, a microwave coil, and a heating coil.

[0280] When the write head only contains a portion rather than all of the data, the processing technology needs to be adjusted locally according to the specific circumstances.

[0281] To facilitate further understanding, the following explanation, in conjunction with accompanying diagrams, further elaborates on some properties and principles of this hard magnetic write head:

[0282] Figure 23 This is a diagram showing the spatial magnetic field lines of a hard magnetic pole. Hard magnetic pole 3 is magnetized in the Z direction. The writing end of the hard magnetic pole is either the N pole or the S pole, and the supporting end of the hard magnetic pole is either the S pole or the N pole. This is a typical magnetic field distribution for a compass.

[0283] Figure 24This diagram shows the magnetic field component distribution at the Z-arm position directly opposite the hard magnetic pole, where 301 and 302 correspond to the two edges of the hard magnetic pole, and 300 is the axis of symmetry. It can be seen that Bx is centrally symmetric with respect to the axis of symmetry, with the same magnitude but opposite signs, while Bz is axially symmetric, unidirectional, and forms a magnetic field plateau in the middle. The maximum value of By is -0.55T, and the value of Bx varies between -0.68T and +0.68T. Since By and Bx are on the same order of magnitude, accurate write operations to the Z-arm are not possible. Therefore, a simple hard magnetic pole is not suitable for a write head.

[0284] Figure 25 The diagram shows the magnetic field lines distribution of the combination of hard magnetic poles and the first soft magnetic shielding layer. A flux concentration effect is formed between the hard magnetic poles 3 and the first soft magnetic flux shielding layer 4.

[0285] Figure 26 This is a diagram showing the magnetic field component distribution at the Z-arm position where the hard magnetic poles are directly opposite each other. It can be seen that the maximum value of By can reach -1.02T, while Bx varies between -0.25T and +0.25T. Therefore, the introduction of the first soft magnetic shielding layer 4 significantly reduces the value of Bx, resulting in an increase in By. Thus, the writing operation of the Z-arm magnetic moment can be achieved, and it can be used for the write head.

[0286] Figure 27 The diagram shows the magnetic field distribution of the combination of hard magnetic poles, the first soft magnetic shielding layer, and the second soft magnetic shielding layer. A flux concentration effect is formed between the hard magnetic pole 3 and the first soft magnetic shielding layer 4 and the second soft magnetic shielding layer 8.

[0287] Figure 28 The diagram shows the magnetic field component distribution at the Z-arm position where the hard magnetic poles are directly opposite each other. It can be seen that the maximum value of By can reach -1.05T, while Bx varies between -0.25T and +0.25T. Therefore, the introduction of the second soft magnetic shielding layer leads to an increase in By, and a decrease in Bx relative to... Figure 25 There is no obvious change, but the second soft magnetic shielding layer 8 can act as a shielding layer to shield external magnetic fields from the support end.

[0288] Figure 29 The diagram shows the magnetic field lines distribution of the hard magnetic pole, the first soft magnetic shielding layer, the second soft magnetic shielding layer, and the third soft magnetic shielding layer. A flux concentration effect is formed between the hard magnetic pole 3, the first soft magnetic flux concentrator 4, and the second soft magnetic shielding layer 8. In addition, a shielding effect is formed between the third soft magnetic shielding layer 10 and the first soft magnetic shielding layer 4.

[0289] Figure 30This is a diagram showing the magnetic field component distribution at the Z-arm position where the hard magnetic poles are directly opposite each other. It can be seen that the maximum value of By can reach -1.07T, while Bx varies between -0.25T and +0.25T. Therefore, the introduction of the third soft magnetic shielding layer leads to an increase in By. Figure 27 and Figure 29 Bx rapidly decreases and remains at 0 in region 10 of the third shielding layer, approximately 30µm away from the edge of 301. At this point, the Bz component remains at +0.25T. Figure 27 In the middle, after leaving the edge of 301, the By value gradually increases, reaching 0.4T. Therefore, the introduction of the third soft magnetic shielding layer 10 can reduce the influence of the stray magnetic field of the hard magnetic pole 3 on the nearby Z-bridge arm and improve the spatial resolution of the hard magnetic pole.

[0290] Figure 31 This is a diagram showing the distribution of magnetic field lines formed by the combination of the stepped hard magnetic poles, the first soft magnetic shielding layer, the second soft magnetic shielding layer, and the third soft magnetic shielding layer.

[0291] Figure 32 This is a diagram showing the magnetic field component distribution at the Z-arm position directly opposite the hard magnetic pole. It can be seen that the maximum value of By can reach -1.15T, while Bx varies between -0.27T and +0.27T. Therefore, the stepped hard magnetic pole acts as a flux concentrator, increasing the By magnetic field.

[0292] Figure 33 This diagram shows the distribution of magnetic field lines penetrating the combined hard magnetic pole, the first soft magnetic shielding layer, the second soft magnetic shielding layer, and the third soft magnetic shielding layer. The hard magnetic pole 3 penetrates the second soft magnetic shielding layer 8. Figure 34 This is a diagram showing the magnetic field component distribution at the Z-arm position where the hard magnetic poles are directly opposite each other. It can be seen that the maximum value of By can reach -1.05T, while Bx varies between -0.25T and +0.25T. Figure 29 The hard magnetic pole 3 in the middle decreases from 1.07T to 1.05T, and there are no other significant changes. However, the hard magnetic pole 3 may be affected by the external magnetic field from the support end.

[0293] Figure 35 To create a combined magnetic field distribution diagram of the penetrating hard magnetic pole, the first soft magnetic shielding layer, the second soft magnetic shielding layer, the third soft magnetic shielding layer, and the fourth soft magnetic shielding layer, a fourth soft magnetic shielding layer 13 is added, located above the penetrating hard magnetic pole 3.

[0294] Figure 36 The diagram shows the magnetic field component distribution at the Z-arm position where the hard magnetic poles are directly opposite. It can be seen that the maximum value of By can reach -1.07T, while Bx varies between -0.25T and +0.25T. However, the introduction of the fourth shielding layer 13 can shield the external magnetic field from the top layer, reducing its impact on the write head.

[0295] Figure 37 This is a typical stacked structure of a Z-axis magnetoresistive sensor unit. Si / SiO2 serves as the substrate 700, (Co / Pt)n 701 and 703 are PMA (perpendicular anisotropic) materials, and Ru 702 is the metal interlayer, forming a (Co / Pt)n / Ru / (Co / Pt)n structure, resulting in two opposing perpendicular magnetic moments. Ru 702 also serves as the seed layer for the pinning layer CoFeB 705. A PMA forms at the interface between CoFeB 705 and the insulating layer MgO 706, and another PMA forms at the interface between the free layer CoFeB 707 and the interlayer MgO 706. The Ta / Ru layer 708 is the cap layer. Together, CoFeB / Ta / (CoPt)n / Ru / (Co / Pt)n forms the pinning layer 7. The actual magnetic tunnel junction is a CoFeB / MgO / CoFeB structure, with 705 as the pinning layer and 707 as the free layer.

[0296] Figure 38 This is a schematic diagram of the rotation of the pinned layer magnetic moment under the action of the Z magnetic field. The DC magnetic field generated by the hard magnetic pole is only the Z component magnetic field, and the X magnetic field component is 0. Assuming that the initial magnetic moment of the Z bridge arm is M0 and the direction of the written magnetic moment is M1, then under the action of the Z component magnetic field, the reversal path can be either the 720 direction or the 721 direction. Therefore, when there is only the Z magnetic field component, the rotation path of the written magnetic moment is uncertain.

[0297] The distribution of Bx at the Z-arm position of the hard magnetic poles shows that Bx has a central symmetry characteristic, with half of it being Bx>0 and the other half being Bx<0. Therefore, the direction of Bx>0 will have a definite path 720, and the direction of Bx<0 will have a definite path 721.

[0298] Figure 39 This is a schematic diagram of the rotation of the magnetic moment of the pinned layer under the combined action of a microwave magnetic field and a DC magnetic field. Figure 39 In the middle, the hard magnetic pole 3 (300) generates a DC magnetic field 79 (300). A microwave current 55 (300) is passed through the microwave coil 5 (300). After passing through the second soft magnetic shielding layer 8 (300) and the third soft magnetic shielding layer 10 (300), a DC magnetic field 79 (300) and a microwave magnetic field 79 (301) are generated at the Z-bridge arm 7 (300) located on the substrate 9 (300). The initial magnetic moment 78 (300) of the Z-bridge arm 7 (300) is in the -Z direction. Figure 39b represents the rotation trajectory of the magnetic moment. At this time, the magnetic moment 78 (300) begins to rotate under the action of the DC magnetic field 79 (300), but it precesses under the microwave magnetic field 79 (301). Thus, the trajectory of the magnetic moment is 725 (300), rotating from the M0 direction to the M1 direction. Accompanied by the DC rotation of the magnetic moment and the microwave precession, the writing of the magnetic moment is completed. The microwave magnetic field makes the writing process of the magnetic moment stable, and its trajectory is constant, ensuring the stability of the magnetic moment writing process of the Z-bridge arm and making it repeatable.

[0299] In this example, all the metal intermediate layers are Ta, Ru, Al, Cu, Pt, Pd or Cr, and the soft shielding layer is an alloy formed by at least one element, Co, Fe or Ni. It may also include soft magnetic alloy materials formed by C, B, N and transition metals or rare earth metals.

[0300] Figure 40 The diagram shows three structural designs of a push-pull bridge Z-axis magnetoresistive sensor. Figure 40 'a' represents a full-bridge structure, containing four Z-arms that require writing. Figure 40 b is a half-bridge structure, containing two Z-arms that need to be written to. Figure 40 c represents a quasi-bridge structure, including two Z-arms that need to be written.

[0301] Figure 41 For reference, see the three structural diagrams of a bridge-type Z-axis magnetoresistive sensor. Figure 41 'a' represents a full-bridge structure, containing two Z-arms that require writing. Figure 41 b is a half-bridge structure, containing one Z-arm that needs to be written to. Figure 41 c represents a quasi-bridge structure, containing one Z-bridge arm that needs to be written.

[0302] from Figure 40 and Figure 41 It can be seen that, corresponding to one Z-axis magnetoresistive sensor, the corresponding Z-bridge arms that need to be written are: 4 Z-bridge arms, corresponding to the full bridge structure of the push-pull bridge Z-axis magnetoresistive sensor; 2 Z-bridge arms, corresponding to the half bridge structure of the push-pull bridge Z-axis magnetoresistive sensor, the full bridge of the reference bridge Z-axis magnetoresistive sensor, and the quasi-bridge of the push-pull bridge Z-axis magnetoresistive sensor; and 1 Z-bridge arm, corresponding to the half bridge and the quasi-bridge of the reference bridge Z-axis magnetoresistive sensor.

[0303] Since the chips on the Z magnetoresistive sensor wafer correspond to the Z-axis magnetoresistive sensor, there can be 4, 2, or 1 chips that need to be written to the Z-bridge arm.

[0304] The cell writing area is the single writing area on the wafer of the Z-axis magnetoresistive sensor corresponding to the write head. It can be a single die on the wafer of the Z-axis magnetoresistive sensor, the exposure area of ​​the mask, or the entire wafer.

[0305] Figure 42 For the distribution of the write head structure Figure 1 The corresponding cell writing region is a single grain. This example only shows the case that includes heating coils and microwave coils. Figure 42 The cell writing region corresponding to a is a die with 4 Z-bridge arms. The write head 600 includes 1 microwave coil 601, 4 heating coils 602, and 4 hard magnetic poles 603. The microwave coil 601 surrounds at least one hard magnetic pole, and in this example, it surrounds 4 hard magnetic poles 603. Figure 42 The cell writing region corresponding to b is the die with two Z-bridge arms. The write head 600(1) includes: one microwave coil 601(1), two heating coils 602(1), and two hard magnetic poles 603(1). In this example, the microwave coil 601(1) surrounds the two hard magnetic poles 603(1). Figure 42 The cell writing region corresponding to c is a die of one Z-bridge arm. The write head 600(2) includes one microwave coil 602(20), one heating coil 602(2), and one hard magnetic pole 603(2). The microwave coil 602(20) surrounds one hard magnetic pole 603(2).

[0306] During operation, the write head performs a write operation on the wafer of the Z-axis magnetoresistive sensor at a rate of completing one Z-axis magnetoresistive sensor die at a time until all dies on the entire wafer are written, thus making the write time the longest.

[0307] Figure 43 For the distribution of the write head structure Figure 2 The corresponding unit writing area is a mask exposure area (reticle) on the wafer of the Z-axis magnetoresistive sensor. Assuming that the mask exposure area contains an M*N die array, and any die (m,n) includes k Z-bridge arms, the corresponding write head includes: an M*N hard magnetic pole unit array. Each hard magnetic pole unit (m,n) includes: k hard magnetic poles, k heating coils, or k heating coils plus one microwave coil surrounding the k hard magnetic poles. M and N are both integers greater than 1, 1≤m≤M, 1≤n≤N, and k=1, 2, or 4. In this example, the mask exposure area 603 includes a 5x5 die array 604, each die 604 comprising 4 Z-bridge arms. The corresponding write head includes a 5x5 hard magnetic pole unit array, each hard magnetic pole unit comprising: 1 microwave coil 605, 4 hard magnetic poles 607, and 4 heating coils 606. The microwave coil surrounds the 4 hard magnetic poles 607, and the 4 heating coils 606 surround the 4 hard magnetic poles 607 respectively. During the write operation, the write operation needs to be performed on the wafer of the Z-axis magnetoresistive sensor at a speed of completing one mask exposure area at a time, then moving to write another exposure area until the entire wafer is written, with the write operation time being moderate.

[0308] Figure 44 For the distribution of the write head structure Figure 3 The cell writing area is the entire wafer. Assuming the wafer includes X*Y mask exposure area arrays, each mask exposure area (x,y) includes M1*N1 die arrays, and each die (x,y,m1,n1) includes k1 Z-bridge arms, then the corresponding write head includes: X*Y*M1*N1 hard magnetic pole unit arrays. Each hard magnetic pole unit (x,y,m1,n1) includes: k1 hard magnetic poles, k1 heating coils, or k1 heating coils plus 1 microwave coil surrounding k1 hard magnetic poles. X,Y,M1,N1 are all integers greater than 1, 1≤x≤X, 1≤y≤Y, 1≤m1≤M1, 1≤n1≤N1, and k1=1, 2, 4. In this example, the wafer 608 of the Z-axis magnetoresistive sensor includes 11*10 array mask exposure areas (reticles) 609. The distribution diagram of the Z-axis magnetoresistive sensor die and write head in each mask exposure area 609 is shown below. Figure 38 As shown, the array includes a 5x5 die array. Each die 604 includes 4 Z-bridge arms. The corresponding write head includes an 11x10x5x5 array of hard magnetic pole units. Each hard magnetic pole unit includes 4 hard magnetic poles 607, 4 heating coils 606, and 1 microwave coil 605 surrounding the 4 hard magnetic poles 607. This allows for writing to a single wafer at the fastest speed, minimizing write operation time, but also resulting in the highest manufacturing cost for the write head.

[0309] Figure 45 For the distribution of the write head structure Figure 4And the writing process, the unit writing area is the entire wafer. Assuming the wafer contains an array of M*N dies, any die is the same and has k Z-bridge arms (1,..., k), then the corresponding write head includes: M*[Pk]ceil(N / k) or [Pk]’ceil(M / k)*N hard magnetic pole arrays. [Pk] or [Pk]’ respectively represent k rows (D1,..., Dk) or columns (D1,..., Dk)’ of hard magnetic pole units arranged adjacent to each other in the X direction or Y direction corresponding to k rows or columns of dies arranged adjacent to each other in the X direction or Y direction. Among them, the Pi hard magnetic pole corresponds to the i-th Z-bridge arm of the Di die, 1 ≤ i ≤ k is an integer, ceil(N / k) or ceil(M / k) represents taking the smallest integer greater than N / k or M / k, and [Pk]ceil(N / k) or [Pk]’ceil(M / k) respectively represent [Pk] rows of hard magnetic pole units repeating Ceil(N / k) times in the X direction or [Pk]’ columns of hard magnetic pole units repeating Ceil(M / k) times in the Y direction. During the writing operation, the hard magnetic write head moves k die positions in sequence in the X direction or Y direction to complete the writing operation of the entire wafer, where k = 1, 2, 4. Specifically in this example, assume the wafer includes an array of 5*5 dies 603(1), each die includes 4 Z-bridge arms (1, 2, 3, 4), and 1, 2, 3, 4 respectively correspond to the 4 positions of the 4 Z-bridge arms in the die. In this example, only the dies arranged adjacent to each other in the X direction are taken as an example. In fact, the dies arranged adjacent to each other in the Y direction can also be used. Then the corresponding write head includes: 5*[P1P2P3P4|P1P2P3P4] hard magnetic pole arrays, where ceil(5 / 4) = 2, indicating that 607[Pk] = (P1P2P3P4) repeats 2 times. For the sake of convenience, only the partial of the second repeating unit (P1P2P3P4) is given in this example. Among them, P1 corresponds to the 1st Z-bridge arm 606(1) in the die 605(1), P2 corresponds to the 2nd Z-bridge arm 606(2) in the die 605(2), P3 corresponds to the 3rd Z-bridge arm 606(3) in the die 605(3), and P4 corresponds to the 4th Z-bridge arm 606(4) in 605(4). And 605(1), 605(2), 605(3) and 605(4) are 4 adjacent dies. 606(1), 606(2), 606(3) and 606(4) respectively correspond to (1, 2, 3, 4), that is, the 4 positions of the Z-bridge arm in the die, as Figure 45 (a) shown.

[0310] The writing process is divided into 4 steps. In the first step, as Figure 45 shown in b, in the die array 603(1), the hard magnetic pole array 607(1) of the write head is in the first phase. In this way, there is the first Z-bridge arm to be written in any Z-axis magnetoresistive sensor die. In the second step, as Figure 45 As shown in c, the write head 607(2) has moved forward by one die relative to the first phase, which is the second phase. Thus, there is a second Z-bridge arm to be written in any Z-axis magnetoresistive sensor die. Step 3, as shown in c. Figure 45 As shown in d, the writing head 607(3) is in the third phase. The third phase is shifted forward by one grain relative to the second phase. Thus, there is a third Z-bridge arm to be written in any Z-axis magnetoresistive sensor grain. Step 4, as shown in d. Figure 45 As shown in Figure e, the write head 607(4) is in the fourth phase. The fourth phase is moved forward by one die relative to the third phase. Thus, there is a fourth Z-bridge arm to be written in any Z-axis magnetoresistive sensor die, and the positions of the first, second, third, and fourth Z-bridge arms are different, forming the four Z-bridge arms of any Z-axis magnetoresistive sensor die. In this way, the writing of the entire wafer can be completed in four steps at the speed of one wafer, thus achieving a speed of less than the number of hard magnetic poles. Figure 43 The write head completes the writing of the entire wafer.

[0311] Figure 46 This diagram illustrates the writing operation of the writing head on the wafer of the Z-axis magnetoresistive sensor. 704 is the wafer test probe station. The wafer 5 of the Z-axis magnetoresistive sensor is placed on the XY wafer stage 703, and the writing head 1 (5) is placed on the probe holder 707. Figure 46 a is the alignment operation between the write head and the wafer of the Z-axis magnetoresistive sensor. The writing end of the write head 1 (5) is imaged by the upward microscope 705 on the XY wafer stage 703, and the wafer 5 of the Z-axis magnetoresistive sensor is imaged by the downward microscope 706 located on the probe seat 707. By manipulating the position of the XY wafer stage 703, the Z bridge arm 63 on the wafer 5 is aligned with the corresponding hard magnetic pole 33' on the write head 1 (5), 62 is aligned with 32', 61 is aligned with 31', and 60 is aligned with 30'. Figure 46 b represents the writing operation of the writing head on the wafer 5 of the Z-axis magnetoresistive sensor. The distance d between the writing end 24 of the writing head 1 (5) and the Z-bridge arms 60-63 on the wafer 5 is about 10um, so as to complete the writing operation of the writing head 1 (5) on the wafer 5. 702 is the first soft magnetic shielding layer, located between the wafer 5 of the Z-axis magnetoresistive sensor and the XY wafer stage 703. It can be located on the back of the wafer 5 of the Z-axis magnetoresistive sensor or on the upper surface of the XY wafer stage 703.

[0312] It also includes an auxiliary heating device, which can be located on the wafer of the Z-axis magnetoresistive sensor or on the probe test stage.

[0313] Figure 47 To write the data to the wafer circuit of the Z-axis magnetoresistive sensor using the write head. Figure 1The write head includes a PCB 802, a hard magnetic pole 801, a first soft magnetic shielding layer 806, a second soft magnetic shielding layer 803, a third soft magnetic shielding layer 805, and a fourth soft magnetic shielding layer 800. It generates a DC magnetic field 810 in the Z-bridge arm 812. On the other hand, a microwave generator 807 is directly coupled to the fourth soft magnetic shielding layer 800 through a capacitor 809. Then, the other end of the microwave is connected to the wafer 804 of the Z-axis magnetoresistive sensor, and the wafer 804 of the Z-axis magnetoresistive sensor is grounded 808. The microwave generates a microwave magnetic field 811 in the air gap between the hard magnetic pole 801 and the Z-bridge arm 812, and acts on the Z-bridge arm 812.

[0314] Figure 48 To write the data to the wafer circuit of the Z-axis magnetoresistive sensor using the write head. Figure 2 , Figure 48 a is a simplified diagram of the write head and wafer structure. The write head includes hard magnetic poles 32' and 33', which are respectively positioned opposite Z-bridge arms 42 and 43 on the wafer, and a microwave coil 81 located at the bottom, which surrounds the Z-bridge arms. In this example, there are four Z-bridge arms. Figure 48 (b) is a schematic diagram of the power supply. The microwave generator 801 is connected to both ends of the microwave coil 81 through a series capacitor 809 (3), and one end is grounded 802. The wafer of the Z-axis magnetoresistive sensor is grounded 802.

[0315] Figure 49 To write the data to the wafer circuit of the Z-axis magnetoresistive sensor using the write head. Figure 3 The microwave coil 802 (3) is equivalent to an inductor L, and a parallel capacitor 809 (3) forms a microwave LC resonant circuit. Then, it is powered by a square wave pulse power supply 807 (3). In this way, the LC resonant forms a high-frequency microwave current 803 (30). One end of the microwave generator is grounded 808 (3), and the wafer of the Z-axis magnetoresistive sensor is grounded 808 (3).

[0316] Figure 50 To write the data to the wafer circuit of the Z-axis magnetoresistive sensor, the microwave coil 802(4) is equivalent to an inductor L and a resistor 805(4)R connected in series. Then, LR and a parallel capacitor 809(4) form a microwave LC resonant circuit, which is then powered by a DC power supply 807(4). This LC resonant circuit generates a high-frequency microwave current 803(40). One end of the microwave generator is grounded 808(4), and the wafer of the Z-axis magnetoresistive sensor is also grounded 808(4). The series resistor 805(4) is used to consume the DC component of the LC circuit, thereby generating a pure microwave component in the microwave coil 802(4).

[0317] Figure 51To write the timing diagram of the coil operation, there are 4 stages: 1) Neither the heating coil nor the microwave coil is energized; 2) The heating coil is energized, but the microwave coil is not energized; 3) The heating coil is not energized, but the microwave coil is energized; 4) Neither the heating coil nor the microwave coil is energized.

[0318] The hard magnetic write head provided in this application, when facing the pinned layer of the Z-bridge arm corresponding to the Z-axis magnetoresistive sensing unit array on the wafer of the Z-axis magnetoresistive sensor, generates a DC write magnetic field containing a Z-axis component in the pinned layer of the Z-bridge arm, thereby causing the magnetic moment of the pinned layer to align with the direction of the DC write magnetic field of the Z-axis component. This provides a simple, fast, and efficient method for writing the magnetic moment of the reference layer of the Z-axis magnetoresistive sensor.

[0319] In embodiments where the magnetic poles are also surrounded by microwave coils, the microwave coils can enhance the magnetic field strength, including the Z-axis component of the DC writing magnetic field, generated in the pinning layer of the Z-bridge arm, thereby improving the efficiency and effectiveness of magnetic moment writing.

[0320] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application. It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0321] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A hard magnetic write head, characterized in that, The writing of the magnetic moment of the pinned layer of the Z-axis magnetoresistive sensing unit array corresponding to the Z-bridge arm on the wafer of the Z-axis magnetoresistive sensor, wherein the Z-bridge arm includes a +Z-bridge arm and / or a -Z-bridge arm, and the hard magnetic writing head and the first soft magnetic shielding layer are respectively located above and below the wafer of the Z-axis magnetoresistive sensor; the hard magnetic writing head includes: The substrate and the hard magnetic pole array disposed on the substrate, wherein the magnetic moment direction of any hard magnetic pole is in the +Z or -Z direction, and the write end is directly opposite one of the Z bridge arms; During writing, the hard magnetic pole writing end generates a DC writing magnetic field containing a Z-axis component in the pinning layer of the Z-bridge arm, thereby causing the magnetic moment of the pinning layer to align with the direction of the Z-axis component DC writing magnetic field.

2. The hard magnetic write head according to claim 1, characterized in that, It also includes a microwave coil array, wherein any microwave coil surrounds at least one of the hard magnetic poles; During the writing process, a microwave current passes through the microwave coil to generate a microwave magnetic field in the pinning layer of the Z-bridge arm.

3. The hard magnetic write head according to claim 1 or 2, characterized in that, The substrate is a PCB, and the hard magnetic pole array is embedded in the PCB.

4. The hard magnetic write head according to claim 3, characterized in that, The hard magnetic poles are: Pre-fabricated permanent magnet installed in the first PCB through-hole of the PCB; Alternatively, a thick-film permanent magnet may be deposited in the first PCB via by a gas flow sputtering method; Alternatively, a composite permanent magnet is formed by filling a mixture of permanent magnet powder and colloid into a second PCB through-hole, wherein the second PCB through-hole includes N-level stepped countersunk holes, and the first stepped countersunk hole is located at the support end of the hard magnetic pole with a cross-sectional dimension of D1, and the Nth stepped countersunk hole is located at the writing end of the hard magnetic pole with a cross-sectional dimension of DN, and D1>D2…>DN, where N is an integer greater than or equal to 3; The first PCB through hole and the second PCB through hole have circular or rectangular cross-sections.

5. The hard magnetic write head according to claim 1 or 2, characterized in that, The substrate is a wafer, and the hard magnetic pole array is located above the wafer substrate.

6. The hard magnetic write head according to claim 1 or 2, characterized in that, It also includes a second soft magnetic shielding layer; The substrate is a PCB, the second soft magnetic shielding layer is located on the first surface layer of the PCB, and the hard magnetic pole support end penetrates the second soft magnetic shielding layer; Alternatively, the substrate is a wafer, and the second soft magnetic shielding layer is located between the wafer substrate and the hard magnetic pole support end.

7. The hard magnetic write head according to claim 1 or 2, characterized in that, It also includes a third soft magnetic shielding layer; The substrate is a PCB, the third soft magnetic shielding layer is located on the second surface layer of the PCB, and the hard magnetic pole writing end penetrates the third soft magnetic shielding layer; Alternatively, the substrate is a wafer, and the third soft magnetic shielding layer is disposed near the end face of the hard magnetic pole writing end and surrounds the hard magnetic pole writing end.

8. The hard magnetic write head according to claim 6, characterized in that, The substrate is a PCB, and the hard magnetic writing head also includes a fourth soft magnetic shielding layer, which is located above the second soft magnetic shielding layer and the hard magnetic pole support end of the PCB.

9. The hard magnetic write head according to claim 1 or 2, characterized in that, It also includes an array of heating coils, which surround the hard magnetic pole writing end and maintain a set gap between the hard magnetic pole and each hard magnetic pole surrounds one of the heating coils.

10. The hard magnetic write head according to claim 2, characterized in that, It also includes a heating coil array, wherein the heating coils surround the hard magnetic pole writing end and maintain a set gap between the hard magnetic poles, and each hard magnetic pole surrounds one of the heating coils; During the data writing process of the pinned layer magnetic moment of the Z-axis magnetoresistive sensor, the heating coil and the microwave coil go through the following four stages: 1) The heating coil and the microwave coil are not energized; 2) The heating coil is energized, while the microwave coil is not energized; 3) The heating coil is not energized, while the microwave writing coil is energized; 4) The heating coil and the microwave coil are not energized.

11. The hard magnetic write head according to claim 1 or 2, characterized in that, The Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor, including one of the +Z bridge arm and the -Z axis bridge arm and a reference bridge arm, and is a half-bridge, full-bridge or quasi-bridge structure. or The Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor, including a +Z-axis bridge arm and a -Z-axis bridge arm, and is a half-bridge, full-bridge, or quasi-bridge structure.

12. The hard magnetic write head according to claim 1, characterized in that, The wafer of the Z-axis magnetoresistive sensor has a single die as its unit writing area. The Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor with a full-bridge structure. The hard magnetic pole array includes four hard magnetic poles, each corresponding to one of the four Z-bridge arms. or The Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor, and has a half-bridge or quasi-bridge structure; or, the Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor, and has a full-bridge structure; the hard magnetic pole array includes two hard magnetic poles, each corresponding to one of the two Z-bridge arms. or The Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor, and has a half-bridge or quasi-bridge structure. The hard magnetic pole array includes one hard magnetic pole, corresponding to one Z-bridge arm.

13. The hard magnetic write head according to claim 2, characterized in that, The wafer of the Z-axis magnetoresistive sensor has a single die as its unit writing area. The Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor with a full-bridge structure. The hard magnetic pole array includes four hard magnetic poles, each corresponding to one of the four Z-bridge arms. The microwave coil array includes one microwave coil that surrounds the four hard magnetic poles. or The Z-axis magnetoresistive sensor is a push-pull bridge magnetoresistive sensor, and has a half-bridge or quasi-bridge structure; or, the Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor, and has a full-bridge structure; the hard magnetic pole array includes two hard magnetic poles, each corresponding to one of the two Z-bridge arms; and the microwave coil array includes one microwave coil surrounding the two hard magnetic poles. or The Z-axis magnetoresistive sensor is a reference bridge magnetoresistive sensor, and has a half-bridge or quasi-bridge structure. The hard magnetic pole array includes one hard magnetic pole, corresponding to one Z-bridge arm. The microwave coil array includes one microwave coil surrounding one hard magnetic pole.

14. The hard magnetic write head according to claim 1, characterized in that, The wafer of the Z-axis magnetoresistive sensor has a cell writing area that is a mask exposure area. The mask exposure area contains M*N die arrays, and any die (m,n) includes k Z-bridge arms. The hard magnetic pole array includes M*N hard magnetic pole units, and each hard magnetic pole unit includes k hard magnetic poles, where 1≤m≤M, 1≤n≤N is an integer, and k = 1, 2, or 4.

15. The hard magnetic write head according to claim 2, characterized in that, The cell writing area of the wafer of the Z-axis magnetoresistive sensor is the exposure area of the mask plate. The exposure area of the mask plate includes an array of M*N grains. Any grain (m,n) includes k Z-bridge arms. The hard magnetic pole array includes: M*N hard magnetic pole units. Each hard magnetic pole unit includes k of the hard magnetic poles. The k hard magnetic poles included in each hard magnetic pole unit are surrounded by one of the microwave coils. 1≤m≤M, 1≤n≤N are integers, and k = 1, 2, or 4.

16. The hard magnetic write head according to claim 1, characterized in that, The cell writing area of the wafer of the Z-axis magnetoresistive sensor is the entire wafer. The wafer includes an array of X*Y exposure areas of the mask plate. Any exposure area (x,y) includes an array of M1*N1 grains. Any grain (x,y,m1,n1) includes k1 Z-bridge arms. The hard magnetic pole array includes: X*Y*M1*N1 hard magnetic pole units. Any hard magnetic pole unit (x,y,m1,n1) includes: k1 of the hard magnetic poles. X, Y, M1, N1 are all integers greater than 1. 1≤x≤X is an integer, 1≤y≤Y is an integer, 1≤m1≤M1 is an integer, 1≤n1≤N1 is an integer, and k1 = 1, 2, 4.

17. The hard magnetic write head according to claim 2, characterized in that, The cell writing area of the wafer of the Z-axis magnetoresistive sensor is the entire wafer. The wafer includes an array of X*Y exposure areas of the mask plate. Any exposure area (x,y) includes an array of M1*N1 grains. Any grain (x,y,m1,n1) includes k1 Z-bridge arms. The hard magnetic pole array includes: X*Y*M1*N1 hard magnetic pole units. Any hard magnetic pole unit (x,y,m1,n1) includes: k1 of the hard magnetic poles. The k1 hard magnetic poles included in each hard magnetic pole unit are surrounded by one of the microwave coils. X, Y, M1, N1 are all integers greater than 1. 1≤x≤X is an integer, 1≤y≤Y is an integer, 1≤m1≤M1 is an integer, 1≤n1≤N1 is an integer, and k1 = 1, 2, 4.

18. The hard magnetic write head according to claim 1 or 2, characterized in that, When the cell writing area of the wafer of the Z-axis magnetoresistive sensor is the entire wafer, the wafer contains an array of M*N grains. Any grain is the same and has k Z-bridge arms (1,…,k); The hard magnetic writing head includes: M*[Pk]ceil(N / k) hard magnetic pole arrays. [Pk] represents k rows of hard magnetic pole units (P1,…,Pk) arranged adjacent to each other in the X direction corresponding to k rows of grains (D1,…,Dk) arranged adjacent to each other in the X direction. The Pi hard magnetic pole corresponds to the i-th Z-bridge arm of the Di grain. 1 = <i≤k is an integer. ceil(N / k) represents the smallest integer greater than N / k. [Pk]ceil(N / k) represents the [Pk] rows of hard magnetic pole units repeated Ceil(N / k) times in the X direction. During the writing operation, the hard magnetic writing head moves k grain positions in sequence along the X direction to complete the writing operation of the entire wafer. Where k = 1, 2, 4; Or, The hard magnetic write head includes: ceil(M / k)*N hard magnetic pole arrays, [Pk]' represents k Y-direction adjacent arranged hard magnetic pole unit columns (P1,..., Pk)' corresponding to k Y-direction adjacent arranged grain columns (D1,..., Dk)'. Among them, the Pi hard magnetic pole corresponds to the i-th Z-bridge arm of the Di grain, 1 ≤ i ≤ k is an integer, ceil(M / k) represents taking the smallest integer greater than M / k, and [Pk]'ceil(M / k) respectively represents the [Pk]' hard magnetic pole unit column repeated Ceil(M / k) times in the Y direction. During the writing operation, the hard magnetic write head moves k grain positions in sequence along the Y direction to complete the writing operation of the entire wafer, where k = 1, 2, 4.

19. The hard magnetic write head according to claim 1 or 2, characterized in that, The Z-axis magnetoresistive sensor stack structure from bottom to top is: (Co / Pt)n / Ta / CoFeB / MgO / CoFeB / Ru / Ta, where the lower CoFeB is the pinned layer.

20. The hard magnetic write head according to claim 1 or 2, characterized in that, The hard magnetic pole support end of the hard magnetic pole is connected to the output end of the microwave generator through a capacitor, and the ground end of the microwave generator is connected to the wafer substrate of the Z-axis magnetoresistive sensor to generate a microwave magnetic field at the gap between the hard magnetic pole writing end and the corresponding Z-axis bridge arm.

21. The hard magnetic write head according to claim 2, characterized in that, The microwave coil, microwave generator, and capacitor are connected in series, and the ground ends of the DC power supply and the microwave generator are connected to the wafer substrate of the Z-axis magnetoresistive sensor.

22. The hard magnetic write head according to claim 2, wherein: A resistor is connected in series at both ends of the microwave coil, and then in parallel with a capacitor, and then powered by a DC power supply; or, the microwave coil is connected in series with a first capacitor, and then in parallel with a second capacitor, and then powered by a DC power supply; or, the microwave coil and the capacitor are connected in parallel at both ends, and then powered by a square wave pulse power supply; Among them, a microwave LC resonance is formed between the microwave coil and the capacitor to generate a microwave magnetic field, and the ground end of the DC power supply is connected to the wafer substrate of the Z-axis magnetoresistive sensor.

23. The hard magnetic write head according to claim 1 or 2, characterized in that, The magnetic directions of the writing ends of a part of the hard magnetic poles in the hard magnetic pole array are opposite to the magnetic directions of the writing ends of the remaining hard magnetic poles.

24. A hard magnetic write head device, characterized in that, Includes the hard magnetic write head according to any one of claims 1 to 23 and the first soft magnetic shielding layer.

25. A hard magnetic data writing system, characterized in that, Includes: The hard magnetic writing head device according to claim 24; And A probe test bench; Among them, during the data writing process, the wafer of the Z-axis magnetoresistive sensor and the hard magnetic write head are both placed on the probe test bench. The wafer of the Z-axis magnetoresistive sensor is placed on the X-Y wafer stage of the probe test bench, and the hard magnetic write head is placed on the probe holder of the probe test bench. The first soft magnetic shielding is located between the wafer of the Z-axis magnetoresistive sensor and the X-Y wafer stage, and the first soft magnetic shielding layer can be located on the back of the wafer of the Z-axis magnetoresistive sensor or on the X-Y wafer stage; By operating the probe test stage, the hard magnetic writing head and the unit writing area of ​​the Z-axis magnetoresistive sensor wafer are positioned and aligned in the XY direction, and the writing spacing in the Z direction is controlled. The writing spacing between the hard magnetic writing head and the Z-axis magnetoresistive sensor wafer is controlled at the working spacing. The hard magnetic write head is positioned and written sequentially to different cell writing areas on the wafer of the Z-axis magnetoresistive sensor by operating the probe holder.

26. The data writing system according to claim 25, characterized in that, The cell writing area can be a single die, a mask exposure area, or the entire wafer on the wafer of the Z-axis magnetoresistive sensor.

27. The data writing system according to claim 25, characterized in that, The system also includes an auxiliary heating device, which is disposed on the wafer of the Z-axis magnetoresistive sensor or on a probe test stage.

28. A method for manufacturing a write head, characterized in that, The method for manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic poles are prefabricated permanent magnets mounted in a first PCB through-hole of a PCB substrate, comprises: 1) Select a double-layer PCB, wherein a second soft magnetic shielding layer and a third soft magnetic shielding layer are respectively provided on the first and second surfaces of the PCB, and both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer; 2) Process a first through hole with a diameter of d, penetrating the double-layer PCB; 3) Process a stepped countersunk hole with a size of D (D>d), wherein the stepped countersunk hole and the first PCB through hole are coaxial; process a first arc groove, a second arc groove, and a third arc groove, wherein the third soft magnetic shielding layer between the first arc groove and the stepped countersunk hole is a heating coil; between the second arc groove and the third arc groove The third soft magnetic shielding layer is a microwave coil. The stepped countersunk hole, the first arc groove, the second arc groove, and the third arc groove all penetrate the third soft magnetic shielding layer and extend into the PCB insulating layer; 4) Place a non-magnetic alignment plate to seal the stepped countersunk hole, and at the same time install the prefabricated permanent magnet in the first PCB through hole, so that the writing end of the prefabricated permanent magnet is aligned with the non-magnetic alignment plate; 5) Remove the non-magnetic alignment plate to obtain the hard magnetic pole array; 6) Deposit a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, and use a non-magnetic metal interlayer to transition between the second soft magnetic shielding layer and the fourth soft magnetic shielding layer.

29. A method for manufacturing a write head, characterized in that, The method for manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic poles are prefabricated permanent magnets mounted in a first PCB through-hole of a PCB substrate, comprises: 1) Select a double-layer PCB, wherein the first and second surface layers of the PCB correspond to the second and third soft magnetic shielding layers, respectively, and both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer; 2) Use PCB processing technology to fabricate the heating coil, microwave coil, and hard magnetic pole window on the third soft magnetic shielding layer, while retaining the third soft magnetic shielding layers between them; 3) Process the first PCB through-hole with a diameter of d, penetrating the double-layer PCB and the hard magnetic pole window; 4) Place a non-magnetic alignment plate to close the first PCB through-hole, and simultaneously install the prefabricated permanent magnet in the first PCB through-hole, so that the writing ends of all the prefabricated permanent magnets are aligned with the non-magnetic alignment plate; 5) Remove the non-magnetic alignment plate to obtain the hard magnetic pole array; 6) Deposit a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, with a non-magnetic metal intermediate layer used as a transition between the second and fourth soft magnetic shielding layers.

30. A method for manufacturing a write head, characterized in that, For manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic poles are thick-film permanent magnets deposited in a first PCB via of a PCB substrate by gas flow sputtering, the method comprising: 1) Select a double-layer PCB, wherein a second soft magnetic shielding layer and a third soft magnetic shielding layer are respectively provided on the first and second surfaces of the PCB. Both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer; 2) Process a stepped countersunk hole with a size of D (D>d), wherein the stepped countersunk hole and the first PCB through hole are coaxial; process a first circular arc groove, a second circular arc groove, and a third circular arc groove, wherein the third soft magnetic shielding layer between the first circular arc groove and the stepped countersunk hole is a heating coil; the third soft magnetic shielding layer between the second circular arc groove and the third circular arc groove is a microwave coil, wherein the stepped countersunk hole, the first circular arc groove, the second circular arc groove, and the third circular arc groove are all... 1) Penetrate the third soft magnetic shielding layer and penetrate into the PCB insulating layer; 2) Spray photoresist as a sacrificial layer to cover the second surface layer of the PCB; 3) Process the first PCB via with a diameter of d, penetrating the PCB and the photoresist layer, and coaxial with the stepped countersunk hole; 4) Place the double-layer PCB on the substrate, align the end of the stepped countersunk hole with the target of the gas flow sputtering thick film deposition equipment, and begin depositing a hard magnetic thick film until the via is filled; 5) Remove the photoresist to obtain a write head containing the hard magnetic poles of the hard magnetic thick film; 6) Deposit a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, with a non-magnetic metal interlayer transitioning between the second soft magnetic shielding layer and the fourth soft magnetic shielding layer.

31. A method for manufacturing a write head, characterized in that, For manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic poles are thick-film permanent magnets deposited in a first PCB via of a PCB substrate by gas flow sputtering, the method comprising: 1) Select a double-layer PCB, wherein a second soft magnetic shielding layer and a third soft magnetic shielding layer are respectively provided on the first and second surfaces of the PCB, and both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer; 2) Use PCB processing technology to fabricate a heating coil, a microwave coil, and a hard magnetic pole window on the third soft magnetic shielding layer, while retaining the third soft magnetic shielding layers between them; 3) Spray photoresist as a sacrificial layer to cover the second surface of the PCB; 4) Process the first PCB via with a diameter of d, penetrating the PCB and the photoresist layer, and coaxial with the stepped countersunk hole; 5) Place the double-layer PCB on the substrate, align the end of the stepped countersunk hole with the target of the gas flow sputtering thick film deposition equipment, and begin depositing a hard magnetic thick film until the via is filled; 6) Remove the photoresist to obtain a write head containing the hard magnetic pole of the hard magnetic thick film; 7) Deposit a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, with a non-magnetic metal intermediate layer as a transition between the second and fourth soft magnetic shielding layers.

32. A method for manufacturing a write head, characterized in that, For manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic pole is a composite permanent magnet formed by filling a second PCB via in a PCB substrate with a mixture comprising permanent magnetic powder and colloid, the method includes: 1) Select a double-layer PCB, wherein a second soft magnetic shielding layer and a third soft magnetic shielding layer are respectively provided on the first and second surface layers of the PCB, and both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer. 2) Using cutting tools of different diameters, process the second PCB through-hole from the first surface layer to the second surface layer; 3) Seal the stepped opening of the second PCB through-hole on the second surface layer with a non-magnetic transparent alignment plate, and place an alignment permanent magnet on the other side of the non-magnetic transparent alignment plate so that the composite permanent magnet has a +Z or -Z polarity; 4) Mix permanent magnet powder and colloid to form a mixture, disperse it on the first surface layer, fill the mixture into the second PCB through-hole, and remove excess magnetic powder; 5) Remove the non-magnetic transparent alignment plate; 6) Process a stepped countersunk hole with a size of D (D>d), the stepped countersunk hole and the second PCB through-hole together Shaft; Machining a first circular arc groove, a second circular arc groove, and a third circular arc groove, wherein the third soft magnetic shielding layer between the first circular arc groove and the stepped countersunk hole is a heating coil; the third soft magnetic shielding layer between the second circular arc groove and the third circular arc groove is a microwave coil, wherein the stepped countersunk hole, the first circular arc groove, the second circular arc groove, and the third circular arc groove all penetrate the third soft magnetic shielding layer and extend into the PCB insulating layer; 7) Depositing a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, wherein a non-magnetic metal interlayer is used for transition between the second soft magnetic shielding layer and the fourth soft magnetic shielding layer.

33. A method for manufacturing a write head, characterized in that, For manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic pole is a composite permanent magnet formed by filling a second PCB via in a PCB substrate with a mixture comprising permanent magnetic powder and colloid, the method includes: 1) Select a double-layer PCB, wherein a second soft magnetic shielding layer and a third soft magnetic shielding layer are respectively provided on the first and second surfaces of the PCB, and both the second and third soft magnetic shielding layers use a non-magnetic intermediate metal layer as a transition layer; 2) Use cutting tools of different diameters to process the second PCB through-holes from the first surface to the second surface; 3) Use a non-magnetic transparent alignment plate to seal the stepped opening of the second PCB through-holes located on the second surface, and place an alignment permanent magnet on the other side of the non-magnetic transparent alignment plate so that the composite permanent magnet has a +Z or -Z polarity; 4) 5) Mix permanent magnet powder and colloid to form a mixture and disperse it on the first surface layer. Fill the mixture into the second PCB via and remove excess magnetic powder; 6) Remove the non-magnetic transparent alignment plate; 7) Use PCB processing technology to fabricate the heating coil, microwave coil, and hard magnetic pole window on the third soft magnetic shielding layer, while retaining the third soft magnetic shielding layer between them; 8) Deposit a fourth soft magnetic shielding layer on the second soft magnetic shielding layer, with a non-magnetic metal interlayer transitioning between the second and fourth soft magnetic shielding layers.

34. A method for manufacturing a write head, characterized in that, For manufacturing a hard magnetic write head according to claim 1, wherein the hard magnetic poles are thick-film permanent magnets deposited in through-holes of a wafer substrate by gas flow sputtering, the method includes: 1) A second soft magnetic shielding layer is deposited on the wafer using a gas flow sputtering method, with a non-magnetic metal interlayer transitioning between the second soft magnetic shielding layer and the wafer; 2) A wet etching stop layer for thick-film hard magnetic poles of permanent magnets is deposited: a thin film of SiO2, Si3N4, or Al2O3; 3) A thick-film permanent magnet is deposited using a gas flow sputtering method; 4) An etching window for the hard magnetic poles of the thick-film permanent magnet is formed using photoresist as a mask; 5) The thick-film permanent magnet is wet-etched, and the photoresist is removed to obtain the hard magnetic pole array of the thick-film permanent magnet; 6) Polyimide is used to fill the gaps and surface of the hard magnetic pole array of the thick-film permanent magnet, and then cured and planarized; 7) The polyimide is thinned by reactive ion etching; 8) A seed layer is sputtered; 9) A heating coil, a microwave coil, and a third soft magnetic shielding layer are electroplated; 10) The seed layer is removed to obtain a write head.

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