JP2010097628A - Thin-film magnetic head with microwave band magnetic driving function and magnetic recording and reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin-film magnetic head with a microwave band magnetic driving function, by which a data signal is precisely written in a magnetic recording medium with a large coercive force without heating and a magnetic field for microwave resonance can be applied to the magnetic recording medium even in a microwave band of a higher frequency, and to provide a magnetic recording and reproducing device provided with the thin-film magnetic head. <P>SOLUTION: The thin-film magnetic head with the microwave band magnetic driving function includes: a write-in magnetic field generation means which generates a write-in magnetic field into the magnetic recording medium according to a write-in signal; and a coplanar type microwave radiator which is provided independently from the write-in magnetic field generation means, radiates the magnetic field for microwave band resonance having a ferromagnetic resonance frequency F<SB>R</SB>of the magnetic recording medium or a frequency in the vicinity thereof when a microwave excitation current is applied, and has an even number of line conductors configured such that a phase difference might arise between flowing microwave excitation currents. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a thin film magnetic head with a microwave band magnetic drive function for writing a data signal on a magnetic recording medium having a large coercive force in order to thermally stabilize the magnetization, and a magnetic comprising the thin film magnetic head. The present invention relates to a recording / reproducing apparatus.

  With the increase in recording density of magnetic recording / reproducing devices represented by magnetic disk drive devices, bit cells of digital information recorded on magnetic recording media have been miniaturized, and as a result, read head elements of thin film magnetic heads due to so-called thermal fluctuations. The signal detected from the signal fluctuates and the S / N (signal to noise ratio) deteriorates. In the worst case, the signal may disappear.

  Therefore, in a magnetic recording medium using a perpendicular magnetic recording method that has been put into practical use in recent years, it is effective to increase the perpendicular magnetic anisotropy energy Ku of the recording film constituting the recording medium. On the other hand, the thermal stability index S corresponding to the thermal fluctuation is expressed by the following formula, and is usually said to be 50 or more.

S = Ku · V / k _B · T (1)
Here, Ku: perpendicular magnetic anisotropy energy, V: volume of crystal grains constituting the recording film, k _B : Boltzmann constant, and T: absolute temperature.

  According to the so-called Stoner-Wolfart model, the anisotropic magnetic field Hk and the coercive force Hc of the recording film are expressed by the following equations. ).

H = Hc = 2Ku / Ms (2)
Where Ms is the saturation magnetization of the recording film.

  In order to perform the magnetization reversal of the recording film corresponding to the intended data series, the write head element of the thin film magnetic head must apply a steep recording magnetic field that is at most about the anisotropic magnetic field Hk of the recording film. . In a magnetic disk drive (HDD) apparatus put into practical use using a perpendicular magnetic recording system, a write head element using a so-called single magnetic pole is used, and recording is performed from the surface of the air bearing surface (ABS) to the recording film in the vertical direction. A magnetic field is applied. Since the intensity of the perpendicular recording magnetic field is proportional to the saturation magnetic flux density Bs of the soft magnetic material forming the single magnetic pole, a material having the highest saturation magnetic flux density Bs has been developed and put to practical use. However, the saturation magnetic flux density Bs has a practical upper limit of Bs = 2.4T (Tesla) from the so-called Slater-Pauling curve, and is approaching the practical limit at present. In addition, the thickness and width of the current single magnetic pole are about 100 to 200 nm. However, when the recording density is increased, it is necessary to further reduce the thickness and width, and accordingly, the generated vertical magnetic field is further reduced. End up.

As described above, it is difficult to perform high-density recording due to the limitation of the recording capability of the write head element. Therefore, so-called heat-assisted magnetic recording (TAMR: Thermal) is performed in which a recording film is irradiated with a laser beam or the like to raise the temperature, and a signal is recorded in a state where the coercive force Hc of the recording film is lowered.
An Assisted Magnetic Recording method has been proposed.

  For example, in Patent Document 1, an electron emission source is used to irradiate a magnetic recording medium with electrons, the recording portion of the magnetic recording medium is heated and heated to lower the coercive force, and then the magnetic recording head uses a magnetic recording head. Information can be recorded. In Patent Document 2, a scatterer constituting a near-field optical probe provided in contact with the main magnetic pole of a perpendicular magnetic recording head is irradiated with laser light using a semiconductor laser element provided in the head. A technique for generating near-field light and applying the near-field light to a magnetic recording medium to increase the temperature of the magnetic recording medium is disclosed.

  However, these heat-assisted magnetic recording systems also have problems due to various technical difficulties.

  For example, 1) a thin film magnetic head on which a magnetic element and an optical element are mounted is essential, but this is extremely complicated in structure and expensive to manufacture. 2) Temperature characteristic change of coercive force Hc It is necessary to develop a large recording film. 3) Thermal demagnetization in the recording process has serious problems such as adjacent track erasure and recording state instability.

  On the other hand, in recent years, research on spin behavior in electron conduction (Spin Transfer) has become active with the aim of increasing the sensitivity of giant magnetoresistive (GMR) read head elements and tunnel magnetoresistive (TMR) read head elements. Research has been started to apply this to the magnetization reversal of the recording film of the magnetic recording medium to reduce the perpendicular magnetic field necessary for the magnetization reversal (Non-patent Document 1, Patent Documents 3 and 4).

  This technique applies a high-frequency AC magnetic field in the in-plane direction of the magnetic recording medium simultaneously with the perpendicular recording magnetic field, and the frequency of the AC magnetic field applied in the in-plane direction corresponds to the ferromagnetic resonance frequency of the recording film. It is an ultra high frequency (several GHz to 10 GHz) in the microwave band. An analysis result has been reported that the required reverse magnetic field in the vertical direction can be reduced to about 60% of the anisotropic magnetic field Hk of the recording film by simultaneously applying the in-plane alternating magnetic field and the perpendicular recording magnetic field. ing. If this technology is put to practical use, it is not necessary to use a TAMR system having a complicated structure, and further, it becomes possible to increase the anisotropic magnetic field Hk of the recording film, so that a great improvement in recording density is expected. .

JP 2001-250201 A JP 2004-158067 A JP 2007-299460 A JP 2008-159105 A J. Zhu, “Recording Well Below Medium Coercivity Assisted by Localized Microwave Utilizing SpinTransfer”, Digest of MMM, 2005

  However, since the conventional microwave magnetic field radiating means is a subcoil provided separately from the write coil or the write coil wound around the magnetic material, when the frequency of the microwave to be applied becomes higher, the portion is increased. Even if the supplied power is increased, the microwave magnetic field cannot be radiated in the direction perpendicular to the magnetic recording medium surface. For this reason, as the frequency of the microwave becomes higher, it becomes extremely difficult to increase the anisotropic magnetic field Hk of the recording film.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a thin film magnetic head with a microwave band magnetic drive function and a thin film magnetic head capable of writing a data signal with high accuracy on a magnetic recording medium having a large coercive force without heating. It is an object of the present invention to provide a magnetic recording / reproducing apparatus including

  Another object of the present invention is to provide a thin film magnetic head with a microwave band magnetic drive function capable of applying a magnetic field for microwave resonance to a magnetic recording medium even in a microwave band having a higher frequency, and the thin film magnetic head. Another object is to provide a magnetic recording / reproducing apparatus.

According to the present invention, the write magnetic field generating means for generating the write magnetic field to the magnetic recording medium in response to the write signal and the write magnetic field generating means are provided independently, and the magnetic field is generated by flowing the microwave excitation current. together to emit ferromagnetic resonance frequency F _R or microwave band resonance magnetic field having a frequency near the recording medium, having an even number of line conductors that are configured to a phase difference from each other in a microwave excitation current is generated that flows A thin-film magnetic head with a microwave band magnetic drive function including a coplanar type microwave radiator is provided.

  A coplanar microwave radiator having an even number of line conductors is provided in the thin film magnetic head instead of a coil wound around a magnetic material, so that an electric field and a magnetic field are generated even in a higher frequency microwave band. Radiation in a direction perpendicular to the magnetic recording medium surface is possible. The coplanar microwave radiator is a radiator that radiates an electromagnetic field by flowing a microwave excitation current through a coplanar waveguide (CPW) that is a kind of planar structure type waveguide.

In particular, the present invention uses a coplanar type microwave radiator having an even number of line conductors configured to cause a phase difference between flowing microwave excitation currents. Is generated in a convex shape, an electric field and a magnetic field are generated in that portion, and as a result, a magnetic field for microwave band resonance can be more effectively applied to the magnetic recording medium. Of course, according to the present invention, it is possible to write a data signal with high accuracy on a magnetic recording medium having a large coercive force without heating. Note that the resonance magnetic field, a high frequency magnetic field of the microwave band having a ferromagnetic resonance frequency F _R or frequency in the vicinity thereof of the magnetic recording layer of the magnetic recording medium. By applying this longitudinal resonance magnetic field to the magnetic recording layer at the time of writing, the coercive force of the magnetic recording layer can be efficiently reduced, and the perpendicular direction required for writing (on the surface of the magnetic recording layer) The writing magnetic field strength in the vertical or substantially vertical direction) can be greatly reduced. That is, by reducing the coercive force, it becomes easier to reverse the magnetization, so that recording can be performed efficiently with a small recording magnetic field.

  The terms used in this specification are defined as follows. In the layer structure of the component formed on the element forming surface of the substrate, the component on the substrate side of the reference layer is assumed to be “below” or “below” the reference layer, and the reference layer It is assumed that the component on the side in which the layers are stacked is “above” or “above” the reference layer. For example, “the lower magnetic pole layer is on the insulating layer” means that the lower magnetic pole layer is located on the side of the direction of lamination with respect to the insulating layer.

  A perpendicular magnetic recording type write head element having a main magnetic pole, an auxiliary magnetic pole, and coil means wound between the main magnetic pole and the auxiliary magnetic pole, and the write magnetic field generating means is the coil means described above, and a coplanar It is preferable that an even number of line conductors of the type microwave radiator are disposed between the main magnetic pole and the auxiliary magnetic pole. In the perpendicular magnetic recording type write head element, since the strongest write magnetic field is generated at the edge on the auxiliary magnetic pole side at the tip of the main pole, by placing at least the line conductor of the microwave radiator at this position, The band resonance magnetic field can be more effectively applied to the magnetic recording medium. In this case, it is more preferable that the two ground conductors of the coplanar type microwave radiator are respectively constituted by the main magnetic pole and the auxiliary magnetic pole.

  Of the even number of line conductors, it is preferable to provide phase shift means for causing the phases of the microwave excitation currents flowing through the two adjacent line conductors to differ from each other by 180 °. In this case, it is more preferable that the phase shift means is connected to the two line conductors, and the transmission line length is composed of two transmission lines different from each other by 1/2 wavelength of the microwave excitation current.

  It is also preferred that the coplanar microwave radiator has two line conductors.

According to the present invention, the magnetic recording medium having the magnetic recording layer, the write magnetic field generating means for generating the write magnetic field to the magnetic recording medium in response to the write signal, and the write magnetic field generating means are provided independently. and by flowing a microwave excitation current causes radiated ferromagnetic resonance frequency F _R or microwave band resonance magnetic field having a frequency near the magnetic recording medium, so that the phase difference from each other in a microwave excitation current flowing occurs A thin film magnetic head including a coplanar type microwave radiator having an even number of line conductors, a write signal supply means for generating a write signal and applying it to the write magnetic field generating means, and a microwave excitation current. A thin film magnet with a microwave driving function with a microwave excitation current supply means applied to a coplanar microwave radiator A magnetic recording / reproducing apparatus including a head is provided.

  A coplanar microwave radiator having an even number of line conductors is provided in the thin film magnetic head instead of a coil wound around a magnetic material, so that an electric field and a magnetic field are generated even in a higher frequency microwave band. Radiation in a direction perpendicular to the magnetic recording medium surface is possible. As described above, the coplanar microwave radiator is a radiator that emits an electromagnetic field by flowing a microwave excitation current through a coplanar waveguide (CPW) that is a kind of planar structure type waveguide. .

In particular, the present invention uses a coplanar type microwave radiator having an even number of line conductors configured to cause a phase difference between flowing microwave excitation currents. Is generated in a convex shape, an electric field and a magnetic field are generated in that portion, and as a result, a magnetic field for microwave band resonance can be more effectively applied to the magnetic recording medium. Of course, according to the present invention, it is possible to write a data signal with high accuracy on a magnetic recording medium having a large coercive force without heating. As described above, the resonance magnetic field, a high frequency magnetic field of the microwave band having a ferromagnetic resonance frequency F _R or frequency in the vicinity thereof of the magnetic recording layer of the magnetic recording medium. By applying this longitudinal resonance magnetic field to the magnetic recording layer at the time of writing, the coercive force of the magnetic recording layer can be efficiently reduced, and the perpendicular direction required for writing (on the surface of the magnetic recording layer) The writing magnetic field strength in the vertical or substantially vertical direction) can be greatly reduced. That is, by reducing the coercive force, it becomes easier to reverse the magnetization, so that recording can be performed efficiently with a small recording magnetic field.

  A perpendicular magnetic recording type write head element having a main magnetic pole, an auxiliary magnetic pole, and coil means wound between the main magnetic pole and the auxiliary magnetic pole, and the write magnetic field generating means is the coil means described above, and a coplanar It is preferable that an even number of line conductors of the type microwave radiator are disposed between the main magnetic pole and the auxiliary magnetic pole. In the perpendicular magnetic recording type write head element, since the strongest write magnetic field is generated at the edge on the auxiliary magnetic pole side at the tip of the main pole, by placing at least the line conductor of the microwave radiator at this position, The band resonance magnetic field can be more effectively applied to the magnetic recording medium. In this case, it is more preferable that the two ground conductors of the coplanar type microwave radiator are respectively constituted by the main magnetic pole and the auxiliary magnetic pole.

  Of the even number of line conductors, it is preferable to provide phase shift means for causing the phases of the microwave excitation currents flowing through the two adjacent line conductors to differ from each other by 180 °. In this case, it is more preferable that the phase shift means is connected to the two line conductors, and the transmission line length is composed of two transmission lines different from each other by 1/2 wavelength of the microwave excitation current.

  It is also preferred that the coplanar microwave radiator has two line conductors.

  One output terminal of the microwave excitation current supply means is connected to the two line conductors via the phase shift means of the coplanar microwave radiator, and the other output terminal of the coplanar microwave excitation current supply means is grounded. It is also preferable that it is connected to the conductor via a resistor.

  It is also preferable to further include a DC excitation current supply circuit that generates a DC excitation current and applies it to the coplanar microwave radiator.

  At the position of the magnetic recording layer of the magnetic recording medium, the writing magnetic field has a direction perpendicular or substantially perpendicular to the surface of the magnetic recording layer, and the resonance magnetic field is in the surface of the surface of the magnetic recording layer or substantially in the surface. It is also preferable that it is set to have a direction.

  According to the present invention, an electric field and a magnetic field can be radiated in a direction perpendicular to the surface of the magnetic recording medium even in a higher frequency microwave band. In particular, the present invention uses a coplanar type microwave radiator having an even number of line conductors configured to cause a phase difference between flowing microwave excitation currents. Is generated in a convex shape, an electric field and a magnetic field are generated in that portion, and as a result, a magnetic field for microwave band resonance can be more effectively applied to the magnetic recording medium. Of course, according to the present invention, it is possible to write a data signal with high accuracy on a magnetic recording medium having a large coercive force without heating.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same constituent elements are denoted by the same reference numerals. In addition, the dimensional ratios in the components in the drawings and between the components are arbitrary for easy viewing of the drawings.

  FIG. 1 is a perspective view schematically showing a configuration of a main part in an embodiment of a magnetic recording / reproducing apparatus according to the present invention. FIG. 2 is a cross-sectional view of a head gimbal assembly (HGA) portion in the magnetic recording / reproducing apparatus of FIG. FIG.

  FIG. 1 shows a magnetic disk drive device as a magnetic recording / reproducing device. In FIG. 1, reference numeral 10 denotes a plurality of magnetic disks rotated around a rotation axis 11 a by a spindle motor 11, and 12 denotes a magnetic disk 10. An HGA 14 for appropriately making the thin film magnetic head (slider) 13 for writing and reading data signals to face the surface of each magnetic disk 10 positions the magnetic head slider 13 on a track of the magnetic disk 10. An assembly carriage device for each is shown.

  The assembly carriage device 14 mainly includes a carriage 16 that can be angularly swung about a pivot bearing shaft 15 and a voice coil motor (VCM) 17 that drives the carriage 16 to be swung angularly. A base of a plurality of drive arms 18 stacked in the direction of the pivot bearing shaft 15 is attached to the carriage 16, and the HGA 12 is fixed to the tip of each drive arm 18. A single magnetic disk 10, a single drive arm 18, and a single HGA 12 may be provided in the magnetic recording / reproducing apparatus.

  In FIG. 1, reference numeral 19 denotes a recording / reproducing and resonance control circuit for controlling the write and read operations of the thin-film magnetic head 13 and controlling the microwave excitation current for ferromagnetic resonance described later.

  As shown in FIG. 2, the HGA 12 has a thin film magnetic head 13, a load beam 20 and a flexure 21 made of a metal conductive material for supporting the thin film magnetic head 13, and a microwave excitation current and a DC excitation current. And an excitation current wiring member 22 which is a transmission line. Although not shown, the HGA 12 has a head element for flowing a write signal applied to the write head element of the thin film magnetic head 13 and for taking out a read output voltage by applying a constant current to the read head element. Wiring members are also provided.

  The thin film magnetic head 13 is attached to one end of an elastic flexure 21. The flexure 21 and the load beam 20 to which the other end is attached constitute a suspension for supporting the thin film magnetic head 13.

  The excitation current wiring member 22 is configured by a strip line having a ground conductor on the upper and lower portions of the entire length. That is, as shown in FIG. 2, copper (Cu) is interposed between the load beam 20 constituting the lower ground conductor and the upper ground conductor 22a via dielectric layers 22b and 22c made of a dielectric material such as polyimide, for example. Thus, the conductor line 22d is sandwiched. As the exciting current wiring member 22, one strip line is formed in parallel with the load beam surface (when the microwave circuit has an unbalanced structure). In this embodiment, the tip of the strip line on the magnetic head side is connected to the terminal electrode by wire bonding using the wire 23. On the other hand, although not shown in the drawing, the wiring members for the write head element and the read head element are formed from ordinary read conductors, and the tips of the wiring head elements are terminals of the write head element and the read head element by wire bonding in this embodiment. Connected to the electrode. You may comprise so that a wiring member and a terminal electrode may be connected by ball bonding, without using wire bonding.

  FIG. 3 is a perspective view schematically showing the entire thin film magnetic head 13 in the present embodiment.

  As shown in the figure, the thin film magnetic head 13 corresponds to a slider substrate 30 having an ABS 30a processed so as to obtain an appropriate flying height, and one side surface when the ABS 30a is a bottom surface. The magnetic head element 31 provided on the vertical element formation surface 30 b, the protection part 32 provided on the element formation surface 30 b so as to cover the magnetic head element 31, and the five exposed from the layer surface of the protection part 32 Terminal electrodes 33, 34, 35, 36 and 37 are provided.

  Here, the magnetic head element 31 mainly includes a magnetoresistive (MR) read head element 31a for reading a data signal from the magnetic disk and an inductive write head element 31b for writing the data signal to the magnetic disk. The terminal electrodes 33 and 34 are electrically connected to the MR read head element 31a, the terminal electrodes 35 and 36 are electrically connected to the inductive write head element 31b, and the terminal electrode 37 is described later. Are electrically connected to one end of two line conductors 38a and 38b (FIG. 4) of the coplanar waveguide (CPW). The other end of the line conductor 38 is grounded (in the case of an unbalanced structure).

  The terminal electrodes 33, 34, 35, 36 and 37 are not limited to the positions shown in FIG. 3, and may be provided in any arrangement on any position on the element formation surface 30b. Further, for example, it may be provided on the slider end surface 30c on the surface opposite to the ABS 30a. Furthermore, when a heater for adjusting the flying height is provided, a terminal electrode electrically connected to the heater is provided.

  In the MR read head element 31a and the inductive write head element 31b, one end of each element reaches the slider end face 30d on the surface on the ABS 30a side. Here, the slider end surface 30 d is a surface other than the ABS 30 a of the medium facing surface facing the magnetic disk of the thin film magnetic head 13, and is a surface mainly composed of the end surface of the protection unit 32. When one end of the MR read head element 31a and the inductive write head element 31b is opposed to the magnetic disk, the data signal is read by sensing the signal magnetic field and the data signal is written by applying the signal magnetic field. Note that an extremely thin coating such as diamond-like carbon (DLC) may be applied to one end of each element reaching the slider end face 30d and the vicinity thereof for protection.

  4 schematically shows the entire thin film magnetic head 13 in the present embodiment, and is a cross-sectional view taken along the line AA in FIG. 3, and FIG. FIG. 6 is a schematic cross-sectional view, FIG. 6 is a view of a part of the configuration of the thin film magnetic head 13 in this embodiment as viewed from the upper surface side with respect to the substrate, and FIG. It is the figure which looked at the structure from the upper surface side with respect to the board | substrate.

4 and 5, reference numeral 30 denotes a slider substrate made of AlTiC (Al ₂ O ₃ —TiC) or the like, and has an ABS 30a facing the surface of the magnetic disk. An MR read head element 31a, an inductive write head element 31b, and two CPW line conductors 38a and 38b described later formed in the inductive write head element 31b on the element forming surface 30b of the slider substrate 30; A protection portion 32 that protects these elements is mainly formed.

MR read head element 31a includes a MR multilayer 31a _1, and a lower shield layer 31a ₂ and the upper shield layer 31a ₃ which are arranged at positions sandwiching the laminate. The MR multilayer 31a ₁ is composed of an in-plane conduction type (CIP) GMR multilayer film, a vertical conduction type (CPP) GMR multilayer film, or a TMR multilayer film, and senses a signal magnetic field from a magnetic disk with very high sensitivity. To do. The lower shield layer 31a ₂ and the upper shield layer 31a ₃ prevent the MR multilayer 31a _{1 from} being affected by an external magnetic field that causes noise.

When the MR laminate 31a ₁ is formed of a CIP-GMR multilayer film, an insulating lower shield gap layer and upper shield gap are provided between the lower shield layer 31a ₂ and the upper shield layer 31a ₃ and the MR laminate 31a _1. Each layer is provided. Further, an MR lead conductor layer for supplying a sense current to the MR multilayer 31a ₁ and taking out a reproduction output is formed. On the other hand, when the MR multilayer 31a ₁ is made of a CPP-GMR multilayer film or a TMR multilayer film, the lower shield layer 31a ₂ and the upper shield layer 31a ₃ also function as upper and lower electrode layers, respectively. In this case, the lower shield gap layer, the upper shield gap layer, and the MR lead conductor layer are unnecessary. Although not shown, on both sides of the track width direction of the MR stack 31a _1, the insulating layer or bias insulating layer for the magnetic domain structure is applied to a vertical bias magnetic field to stabilize and the hard bias layer is formed The

For example, when the MR laminate 31a ₁ includes a TMR multilayer film, the MR laminate 31a ₁ is made of iridium manganese (IrMn), platinum manganese (PtMn), nickel manganese (NiMn), ruthenium rhodium manganese (RuRhMn), or the like. An antiferromagnetic layer and, for example, two ferromagnetic films such as cobalt iron (CoFe) are composed of a three-layer film sandwiching a nonmagnetic metal film such as ruthenium (Ru). The fixed magnetization pinned layer and a metal film having a thickness of about 0.5 to 1 nm made of, for example, aluminum (Al), aluminum copper (AlCu), magnesium (Mg), or the like, are added by oxygen introduced into the vacuum apparatus or A tunnel barrier layer made of a nonmagnetic dielectric film oxidized by natural oxidation and a thickness of 1 nm made of, for example, CoFe Exchange with a magnetization fixed layer via a tunnel barrier layer, which consists of a ferromagnetic film with a thickness of about 3 to 4 nm and a ferromagnetic film made of nickel iron (NiFe) or the like. A magnetization free layer that forms a coupling has a structure in which the layers are sequentially stacked.

Further, the lower shield layer 31a ₂ and the upper shield layer 31a ₃ are formed of, for example, NiFe (permalloy or the like) having a thickness of about 0.1 to 3 μm and cobalt iron nickel formed by using a pattern plating method including a frame plating method. (CoFeNi), CoFe, iron nitride (FeN), or iron zirconium nitride (FeZrN) film.

Inductive write head element 31b is for perpendicular magnetic recording, from the end of the write time of the own ABS30a (slider end surface 30d) side of the data signal and the main magnetic pole layer 31b ₁ as the main magnetic poles generated in the write magnetic field, the trailing A gap layer 31b ₂ , a write coil 31b ₃ having a spiral shape and passing between the main magnetic pole layer and the auxiliary magnetic pole layer for at least one turn, and a write coil insulating layer 31b ₄ Auxiliary magnetic pole layer 31b ₅ as an auxiliary magnetic pole in which a portion separated from the end portion on the ABS 30a (slider end surface 30d) side is magnetically connected to main magnetic pole layer 31b _1; and auxiliary shield layer 31b ₆ as an auxiliary shield; , and a leading gap layer 31b _7.

The main magnetic pole layer 31b ₁ is a magnetic path for guiding the magnetic flux generated by applying the write current to the write coil 31b ₃ while converging it to the magnetic recording layer of the magnetic disk to be written. and a yoke layer _{31b 11} and the main magnetic pole main layer _{31b 12.} Here, the main magnetic pole layer 31b ₁ ABS30a the thickness direction length at the end of the (slider end surface 30d) side (thickness), decreases and corresponds to the layer thickness of the main magnetic pole main layer _{31b 12} only ing. As a result, when writing a data signal, a fine write magnetic field corresponding to a higher recording density can be generated from this end. The main magnetic pole yoke layer 31b ₁₁ and the main magnetic pole main layer 31b ₁₂ are formed by using, for example, a sputtering method, a pattern plating method including a frame plating method, etc., and have a thickness of about 0.5 to 3.5 μm, respectively. It is composed of a NiFe, CoFeNi, CoFe, FeN or FeZrN film having a thickness of about 0.1 to 1 μm.

Auxiliary pole layer 31b ₅ and the auxiliary shield layer 31b _6, respectively, are disposed on the trailing side and the leading side of the main magnetic pole layer 31b _1. Auxiliary pole layer 31b _5, as described above, ABS30a but spaced portions to the end portions of the (slider end surface 30d) side is the main magnetic pole layer 31b ₁ and magnetically coupled, the auxiliary shield layer 31b ₆ is not the main magnetic pole layer 31b ₁ and magnetically connected in this embodiment.

End of the slider end surface 30d side of the auxiliary magnetic pole layer 31b ₅ and the auxiliary shield layer 31b _6, respectively, the layer cross-section has a broad trailing shield section _{31b 51} and the leading shield section _{31b 61} than other portions. Trailing shield section _{31b 51} is opposed through the end portion and the trailing gap layer 31b ₂ of the slider end surface 30d side of the main magnetic pole layer 31b _1. Further, the leading shield section _{31b 61} is opposed through the end portion and the leading gap layer 31b ₂ of the slider end surface 30d side of the main magnetic pole layer 31b _1. By providing the trailing shield part 31b ₅₁ and the leading shield part 31b ₆₁ as described above, due to the shunt effect of the magnetic flux, between the trailing shield part 31b ₅₁ and the end of the main magnetic pole layer 31b ₁ and the leading shield part 31b. magnetic field gradient of the write field between the end portion and the end portion of the main magnetic pole layer 31b _{1 61} becomes steeper. As a result, the jitter of the signal output is reduced, and the error rate at the time of reading can be reduced.

The auxiliary magnetic pole layer 31b ₅ or the auxiliary shield layer 31b ₆ is appropriately processed, and a part of the auxiliary magnetic pole layer 31b ₅ or the auxiliary shield layer 31b ₆ is arranged near both sides of the main magnetic pole layer 31b _{1 in} the track width direction. Thus, it is possible to provide a so-called side shield. In this case, the shunt effect of magnetic flux is enhanced.

The length (thickness) of the trailing shield part 31b ₅₁ and the leading shield part 31b _{61 in} the layer thickness direction is set to about several tens to several hundreds times the thickness of the main magnetic pole layer 31b _{1 in} the same direction. It is preferable. In addition, the gap length of the trailing gap layer 31b ₂ is preferably about 10 to 100 nm, and more preferably about 20 to 50 nm. Further, the gap length of the leading gap layer 31b ₇ is preferably 0.1μm or more.

The auxiliary magnetic pole layer 31b ₅ and the auxiliary shield layer 31b ₆ are formed of, for example, a NiFe, CoFeNi, CoFe, FeN, or FeZrN film having a thickness of about 0.5 to 4 μm formed by using a pattern plating method including a frame plating method. It is composed of In addition, the trailing gap layer 31b ₂ or the leading gap layer 31b ₇ is formed by using, for example, alumina (Al ₂ O ₃ ) or silicon oxide (0.1 to ₃ μm thick) formed by sputtering, CVD, or the like. SiO ₂ ), aluminum nitride (AlN), DLC film, or the like.

As shown in FIG. 6, a write signal is passed through the write coil 31b ₃ via the lead conductor 31b ₃₁ , the via-hole conductors 31b ₃₂ , 31b _33, 31b _{34, and the} like. Write coil insulating layer 31b ₄ surrounds the write coil 31b _3, is provided in order to electrically insulate the write coil 31b ₃ from around the magnetic layer. The write coil 31b ₃ is made of, for example, a Cu film having a thickness of about 0.1 to 5 μm formed by using a frame plating method, a sputtering method, or the like. The lead conductor 31b _{31 and the} via-hole conductors 31b ₃₂ , 31b ₃₃ and 31b ₃₄ are also composed of, for example, a Cu film formed using a frame plating method, a sputtering method, or the like. The write coil insulation layer 31b ₄ are formed, for example, a photoresist or the like which is heat curing thickness of about 0.5~7μm which are formed by photolithography or the like.

As shown in FIGS. 4 to 7, in this embodiment, the CPWs are parallel to each other between the main magnetic pole main layer 31 b ₁₂ of the main magnetic pole layer 31 b ₁ and the trailing shield part 31 b ₅₁ of the auxiliary magnetic pole layer 31 b _5. Two line conductors 38a and 38b are formed. Furthermore, in this embodiment, the main magnetic pole layer 31b ₁ (main magnetic pole main layer 31b ₁₂ ) and the auxiliary magnetic pole layer 31b ₅ (trailing shield portion 31b ₅₁ ) constitute two ground conductors of CPW. Therefore, the main magnetic pole layer 31b ₁ and the auxiliary magnetic pole layer 31b ₅ are grounded via a resistor or the like.

One end of the line conductor 38a is grounded via a lead conductor 38a ₁ and the via hole conductors 38a ₃ and 38b _3, the other end via a lead conductor 38a ₂ and the via hole conductors 38a ₄ and 38b _4, further excitation current wire The member 22 (FIG. 2) is connected to the output terminal of the excitation current supply circuit. One end of the line conductor 38b is grounded via a lead conductor 38b ₁ and the via hole conductors 38b _3, the other end via a lead conductor 38b ₂ and the via hole conductors 38b _4, further excitation current interconnection member 22 (FIG. 2) via the output terminal of the excitation current supply circuit.

Thus, the line conductor 38a, which is a microwave radiator, is passed from the microwave oscillator of the excitation current supply circuit via the via-hole conductors 38b ₄ and 38a ₄ , the lead conductors 38a ₂ and 38a ₁ and the via-hole conductors 38a ₃ and 38b ₃ . Thus, microwave excitation currents having a phase difference are supplied. Further, a phase difference is given to the line conductor 38b which is a microwave radiator from the microwave oscillator of the excitation current supply circuit via the via-hole conductor 38b ₄ , the lead conductors 38b ₂ and 38b ₁ and the via-hole conductor 38b _3. Microwave excitation current is applied.

In the middle of the lead conductor 38b ₂ connected to the other end of the line conductor 38b, a phase shift portion 38b ₅ having a length corresponding to ½ wavelength of the microwave excitation current is formed. The transmission line to the conductor 38b is longer than the transmission line to the line conductor 38a by ½ wavelength, and the phases of the microwave excitation currents can be different from each other by 180 °. In the example shown in FIGS. 6 and 8, the phase shift portion 38 b ₅ is a rectangular line, but any shape may be used. If a partial circular line is used, it is possible to save some space.

In the present embodiment, the length in the track width direction of the line conductor 38a and 38b have substantially equal to the length in the track width direction of the main magnetic pole main layer 31b ₁₂ of the main magnetic pole layer 31b _1. The line conductors 38a and 38b, the lead conductors 38a ₁ , 38a ₂ , 38b ₁ and 38b ₂ , the phase shift part 38b _{5 and the} via-hole conductors 38a ₃ , 38a ₄ , 38b ₃ and 38b ₄ are formed using, for example, a sputtering method. It is composed of a Cu film or the like.

As described above, in the present embodiment, the main magnetic pole layer 31b ₁ and the auxiliary magnetic pole layer 31b ₅ are configured as the CPW ground conductor, and two lines of CPW are provided between the main magnetic pole layer 31b ₁ and the auxiliary magnetic pole layer 31b _5. Conductors 38a and 38b are provided. In this case, the trailing gap layer 31b ₂ corresponds to the dielectric substrate. The distance between the main magnetic pole layer 31b ₁ and the auxiliary magnetic pole layer 31b ₅ is, for example, about 30 to 40 nm, because the gap between the surface of the line conductor 38 and the magnetic disk 10 of the thin-film magnetic head is, for example, 3nm approximately, present Even if the two line conductors 38a and 38b are provided between the main magnetic pole layer and the auxiliary magnetic pole layer as in the embodiment, the CPW can be configured in a microwave.

By flowing a microwave excitation current in these line conductors 38a and 38b, between the end portion and the trailing shield portion 31b ₅₁ of the main magnetic pole layer 31b _1, lines of electric force generated toward the surface of the magnetic disk 10, A resonance magnetic field in the longitudinal direction (in the plane of the magnetic disk surface or substantially in the plane and in the track direction), which is a direction perpendicular to the electric field lines, is radiated. The resonance magnetic field is a high frequency magnetic field of the microwave band having a ferromagnetic resonance frequency F _R or frequency in the vicinity thereof of the magnetic recording layer of the magnetic disk 10. By applying this longitudinal resonance magnetic field to the magnetic recording layer at the time of writing, the writing magnetic field strength in the vertical direction (direction perpendicular to or substantially perpendicular to the surface of the magnetic recording layer) required for writing is greatly reduced. be able to.

  When the resonance magnetic field is radiated only by the microwave as described above, a large high-frequency current is required. The microwave power to be applied can be reduced by flowing the current superimposed on 38b.

  Next, the effect of the CPW according to the present embodiment having the two line conductors 38a and 38b will be described in comparison with a conventional general CPW.

  A conventional general CPW has a structure in which one line conductor 92 is formed between two ground conductors 91a and 91b on a dielectric substrate 90 as shown in FIG. The signal line is configured to pass a high frequency current. In the CPW, as shown in FIGS. 9B and 9C, since there is no ground conductor above the signal conductor 92, the lines of electric force emitted from the signal conductor 92 are ground conductors in the horizontal direction. 91a and 91b are entered as they are. Therefore, according to the conventional single-phase driving method, no electric lines of force are generated above the signal conductor 92, so that neither an electric field nor a magnetic field is generated directly above the signal conductor 92. It becomes.

  FIG. 10 shows a simulation characteristic of angle versus radiated power in a conventional general CPW driven by a single signal conductor in order to express this characteristic. As is clear from FIG. 10, a depression is formed in the center of the radiated electric field or magnetic field. (A weakly radiated part) is created. The formation of a dent just above the center of the signal conductor 92 is not preferable because the microwave power in this portion is reduced.

  On the other hand, the CPW of this embodiment has a structure in which two line conductors 112a and 112b are formed between two ground conductors 111a and 111b on a dielectric substrate 110 as shown in FIG. These two signal lines are configured to pass high-frequency currents having a phase difference from each other. As described above, there is no ground conductor above the signal conductor in the CPW. However, in this embodiment, two signal conductors are provided, and a phase difference is provided between the two to cause the electric lines of force to be output directly above. It is devised as follows. That is, as shown in FIG. 11, by applying a phase difference, an electric field line is generated between the two line conductors 112a and 112b, and this generates an electric field and a magnetic field at the center of the line conductors 112a and 112b. Will be allowed to.

  In order to express this characteristic, FIG. 12 shows a simulation characteristic of angle vs. radiated power in the CPW of the present embodiment by two signal line differential driving. As is clear from FIG. A radiation electric field or magnetic field is generated, and sufficient microwave power can be applied to the magnetic recording medium.

  In particular, in the present embodiment, when the phase of the microwave excitation current flowing through the two line conductors of the CPW is different by 180 °, the maximum potential difference is generated between the two lines. A large electric field and magnetic field are generated at the center of 112b (38a and 38b), and as a result, the magnetic field for microwave band resonance can be more effectively applied to the magnetic recording medium.

  FIG. 13 is a sectional view for explaining the principle of the magnetic recording method using the magnetic field for ferromagnetic resonance according to the present invention and showing the head model of the above-described embodiment.

  First, the structure of the magnetic disk 10 will be described with reference to FIG. The magnetic disk 10 is for perpendicular magnetic recording. On the disk substrate 10a, a magnetic orientation layer 10b, a soft magnetic backing layer 10c that functions as a part of a magnetic flux loop circuit, an intermediate layer 10d, a magnetic recording layer 10e, It has a multilayer structure in which a conductive protective layer 10f is sequentially stacked, and all layers including the disk substrate 10a are formed of a conductive material.

  The magnetization orientation layer 10b stabilizes the magnetic domain structure of the soft magnetic backing layer 10c by giving magnetic anisotropy in the track width direction to the soft magnetic backing layer 10c, thereby suppressing spike noise in the reproduced output waveform. ing. The intermediate layer 10d serves as an underlayer for controlling the magnetization orientation and grain size of the magnetic recording layer 10e.

  Here, the disk substrate 10a is made of nickel phosphorus (NiP) -coated Al alloy, silicon (Si), or the like. The magnetization alignment layer 10b is made of PtMn or the like that is an antiferromagnetic material. The soft magnetic underlayer 10c is made of a cobalt (Co) amorphous alloy such as cobalt zirconium niobium (CoZrNb), an iron (Fe) alloy, soft magnetic ferrite, or the like, or a soft magnetic film / non-magnetic multilayer film. Etc. are formed. The intermediate layer 10d is made of a Ru alloy or the like that is a nonmagnetic material. Here, the intermediate layer 10d may be another non-magnetic metal or alloy, or a low-permeability alloy as long as the perpendicular magnetic anisotropy of the magnetic recording layer 10e can be controlled. The protective layer 10f is formed of a carbon (C) material or the like by a chemical vapor deposition (CVD) method or the like.

The magnetic recording layer 10e is formed of, for example, a cobalt chromium platinum (CoCrPt) -based alloy, CoCrPt—SiO ₂ , an iron platinum (FePt) -based alloy, or a CoPt / palladium (Pd) -based artificial lattice multilayer film. In the magnetic recording layer 10e, the perpendicular magnetic anisotropy energy is adjusted to, for example, 1 × 10 ⁶ erg / cc (0.1 J / m ³ ) or more in order to suppress thermal fluctuation of magnetization. Is preferred. In this case, the value of the coercive force of the magnetic recording layer 10e is, for example, about 5 kOe (400 kA / m) or more. Furthermore, the ferromagnetic resonance frequency F _R of the magnetic recording layer 10e, the shape of the magnetic particles constituting the magnetic recording layer 10e, size, is a unique value determined by the constituent elements or the like, and generally 1~15GHz about It has become. The ferromagnetic resonance frequency F _R is In some cases only one is present, as when a spin wave resonance occurs, there is a case where there are a plurality.

Next, the principle of the magnetic recording method according to the present invention will be described with reference to FIG. By applying a microwave excitation current to the CPW, electric lines of force are generated toward the surface of the magnetic disk 10, and the track is in the in-plane or substantially in-plane direction of the magnetic disk surface that is perpendicular to the electric lines of force. A resonance magnetic field 130 is emitted in the direction. The resonance magnetic field 130, because it is a high-frequency magnetic field of a microwave band having a frequency of ferromagnetic resonance frequency F _R or near the magnetic recording layer 10e of the magnetic disk 10, effectively the coercivity of the magnetic recording layer 10e As a result, the write magnetic field strength in the perpendicular direction (direction perpendicular to or substantially perpendicular to the surface of the magnetic recording layer 10e) required for writing can be greatly reduced. That is, by reducing the coercive force, it becomes easier to reverse the magnetization, so that recording can be performed efficiently with a small recording magnetic field.

In fact, by applying the resonance magnetic field having a ferromagnetic resonance frequency F _R of the magnetic recording layer, for example, the vertical direction of the write magnetic field can reverse the magnetization of the magnetic recording layer 10e was reduced by about 40%, 60 % Can be achieved. That is, even if the coercive force of the magnetic recording layer 10e before applying the resonance magnetic field is about 5 kOe (400 kA / m), this coercive force can be obtained by applying the resonance magnetic field in the in-plane direction of the magnetic recording layer. Can be effectively reduced to about 2.4 kOe (192 kA / m).

The intensity of the resonance magnetic field is the anisotropy field of the magnetic recording layer as _{H K,} more preferably about 0.1H _K ~0.2H _K, its frequency, the material of the magnetic recording layer 10e Depending on the layer thickness and the like, it is preferably about 1 to 15 GHz.

  FIG. 14 is a block diagram schematically showing the electrical configuration of the magnetic disk drive apparatus according to this embodiment.

  In the figure, 11 is a spindle motor that rotates the magnetic disk 10, 140 is a motor driver that is a driver of the spindle motor 11, 141 is a VCM driver that is a driver of the VCM 17, 142 is a motor driver 140 under the control of the computer 143. And a hard disk controller (HDC) for controlling the VCM driver 141, 144 is a read / write IC circuit including a head amplifier 144a and a read / write channel 144b of the thin film magnetic head 13, and 145 is an excitation current for supplying a microwave excitation current and a DC excitation current. A supply circuit 146 indicates a head element wiring member for flowing a write signal applied to the write head element and for applying a constant current to the read head element to extract a read output voltage. One output terminal of the excitation current supply circuit 145 is connected to one end of the two signal conductors 38a and 38b of the thin film magnetic head 13 via the excitation current wiring member 22 and the like, and the other output terminal is grounded. .

  The recording / reproducing and resonance control circuit 19 shown in FIG. 1 includes the above-described HDC 142, computer 143, read / write IC circuit 144, excitation current supply circuit 145, and the like.

  As described above, according to the present embodiment, not the coil wound around the magnetic body but the CPW which is an example of the planar structure type microwave radiator is used, and the two line conductors 38a and 38b are connected. Since it is provided in the thin film magnetic head, an electric field and a magnetic field can be radiated in the direction of the magnetic disk even in a higher frequency microwave band. Of course, according to the present embodiment, it is possible to write a data signal with high accuracy on a magnetic disk having a large coercive force without heating.

  In the present embodiment, in particular, the microwave radiator is configured by CPW having two line conductors 38a and 38b, and is configured such that a phase difference occurs between the microwave excitation currents flowing between the line conductors 38a and 38b. Thus, as in the case of CPW with a single line conductor, the two line conductors 38a and 38a and Since the lines of electric force are incident and exited between 38b, strong radiation can be applied to the magnetic disk 10 without generating a weak radiation portion in the center of the radiation electric field, that is, the radiation magnetic field. Furthermore, since the return of the lines of electric force is applied substantially perpendicularly rather than in parallel with the surface of the magnetic disk, the direction of the magnetic field is parallel (longitudinal direction) to the surface of the magnetic disk. The writing magnetic field strength in a direction perpendicular or substantially perpendicular to the surface of the magnetic recording layer can be greatly reduced. In addition, in this embodiment, the phase of the microwave excitation current flowing through the two line conductors of the CPW is changed by 180 °, and the maximum potential difference is generated between the two lines, so that the center of the line conductors 38a and 38b is larger. Electric and magnetic fields can be generated.

  Further, in the write head element of the perpendicular magnetic recording structure as in the present embodiment, the strongest write magnetic field is generated at the edge near the auxiliary magnetic pole side at the tip of the main magnetic pole. By arranging the magnetic pole layers between the magnetic pole layers, the magnetic field for microwave band resonance can be applied to the magnetic disk 10 more effectively.

  Thus, it is understood that data signals can be written with high accuracy on a magnetic disk having a large coercive force without using so-called thermal assist (heating). Furthermore, such a magnetic recording method can be realized without using a special element that imposes a heavy burden such as an electron emission source and a laser light source, and the size and cost can be reduced.

  As a modification of this embodiment, two line conductors may be arranged on the side opposite to the auxiliary magnetic pole with respect to the main magnetic pole. However, in this case, since the position of the line conductor is shifted from the position where the strongest write magnetic field is generated, the effect of applying the magnetic field for microwave band resonance is somewhat lower than in the case of the above-described embodiment.

  Although the configuration of the thin film magnetic head 13 has been described in detail above, the thin film magnetic head of the present invention is not limited to the configuration described above, and it is obvious that other various configurations can be adopted.

  In the above-described embodiment, a CPW having two line conductors is used as the microwave radiator. However, it is obvious that a CPW having four or more even number of line conductors may be used. is there.

  All the embodiments described above are illustrative of the present invention and are not intended to be limiting, and the present invention can be implemented in other various modifications and changes. Therefore, the scope of the present invention is defined only by the claims and their equivalents.

1 is a perspective view schematically showing a configuration of a main part in an embodiment of a magnetic recording / reproducing apparatus according to the present invention. It is sectional drawing of the part of HGA in the magnetic recording / reproducing apparatus of FIG. FIG. 2 is a perspective view schematically showing an entire thin film magnetic head in the embodiment of FIG. 1. FIG. 4 is a schematic cross-sectional view taken along line AA of FIG. 3 while schematically showing the whole thin film magnetic head in the embodiment of FIG. 1. It is sectional drawing which shows schematically the structure which looked at the thin film magnetic head in embodiment of FIG. 1 from the ABS side. It is the figure which looked at the structure of a part of thin film magnetic head in embodiment of FIG. 1 from the upper surface direction with respect to the board | substrate. It is the figure which looked at the structure of a part of thin film magnetic head in embodiment of FIG. 1 from the upper surface direction with respect to the board | substrate. FIG. 2 is a block diagram schematically illustrating a configuration of a CPW in the embodiment of FIG. It is a figure which shows the structure of the conventional general CPW. It is a characteristic view showing the simulation characteristic of the angle versus radiation power in the conventional general CPW. It is a figure which shows the structure of CPW in embodiment of FIG. It is a characteristic view showing the simulation characteristic of angle versus radiation power in CPW in the embodiment of FIG. FIG. 2 is a cross-sectional view illustrating the principle of the magnetic recording method according to the present invention and showing the head model of the embodiment of FIG. 1. FIG. 2 is a block diagram schematically showing an electrical configuration of the magnetic disk drive device in the embodiment of FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Magnetic disk 10a Disk board | substrate 10b Magnetization orientation layer 10c Soft magnetic backing layer 10d Intermediate | middle layer 10e Magnetic recording layer 10f Protective layer 11 Spindle motor 12 HGA
13 Thin Film Magnetic Head 14 Assembly Carriage Device 15 Pivot Bearing Shaft 16 Carriage 17 VCM
18 Drive Arm 19 Recording / Reproducing and Resonance Control Circuit 20 Load Beam 21 Flexure 22 Excitation Current Wiring Member 22a Upper Ground Conductor 22b, 22c Dielectric Layer 22d Conductor Line 23 Wire 30 Slider Substrate 30a ABS
30b Element formation surface 30c, 30d Slider end face 31 Magnetic head element 31a MR read head element 31a ₁ MR stack 31a ₂ Lower shield layer 31a ₃ Upper shield layer 31b Inductive write head element 31b ₁ main pole layer 31b ₁₁ main pole yoke layer 31b ₁₂ main pole main layer 31b ₂ trailing gap layer 31b ₃ writing coil 31b ₄ writing coil insulating layer 31b ₅ auxiliary magnetic pole layer 31b ₅₁ trailing shield part 31b ₆ auxiliary shield layer 31b ₆₁ leading shield part 31b ₇ leading gap layer 32 protection part 33, 34, 35, 36, 37 Terminal electrode 38a, 38b, 92, 112a, 112b Signal conductor 90, 110 Dielectric substrate 91a, 91b, 111a, 111b Ground conductor 130, 131 Magnetic flux 40 motor driver 141 VCM driver 142 HDC
143 Computer 144 Read / write IC circuit 144a Head amplifier 144b Read / write channel 145 Excitation current supply circuit 146 Head element wiring member

Claims (15)

A write magnetic field generating means for generating a write magnetic field to the magnetic recording medium in response to a write signal and the write magnetic field generating means are provided independently of each other, and the magnetic recording medium is strengthened by flowing a microwave excitation current. together emit a magnetic field for a microwave band resonance with magnetic resonance frequency F _R or frequency near the coplanar microwave having an even number of line conductors that are configured to a phase difference from each other in a microwave excitation current is generated that flows A thin film magnetic head with a microwave band magnetic drive function, characterized by comprising a radiator.   A perpendicular magnetic recording type write head element having a main magnetic pole, an auxiliary magnetic pole, and coil means wound between the main magnetic pole and the auxiliary magnetic pole, and the write magnetic field generating means is the coil means 2. The thin film magnetic head according to claim 1, wherein the even number of line conductors of the coplanar type microwave radiator are disposed between the main magnetic pole and the auxiliary magnetic pole.   3. The thin film magnetic head according to claim 2, wherein two ground conductors of the coplanar microwave radiator are constituted by the main magnetic pole and the auxiliary magnetic pole, respectively.   4. The phase shift means for shifting the phase of the microwave excitation current flowing through the two adjacent line conductors among the even number of line conductors by 180 ° from each other is provided. 5. The thin film magnetic head described in 1.   The phase-shifting means is connected to the two line conductors, respectively, and consists of two transmission lines whose line lengths are different from each other by a half wavelength of the microwave excitation current. Thin film magnetic head.   6. The thin film magnetic head according to claim 1, wherein the coplanar type microwave radiator has two line conductors. A magnetic recording medium having a magnetic recording layer, a write magnetic field generating means for generating a write magnetic field to the magnetic recording medium in response to a write signal, and a microwave excitation current provided independently of the write magnetic field generating means an even number of the causes radiated magnetic field microwave band resonance having ferromagnetic resonance frequency F _R or frequency in the vicinity thereof of the magnetic recording medium, which is configured so that the phase difference from each other in a microwave excitation current flowing occurs by flowing Thin film magnetic head including a coplanar type microwave radiator having a line conductor, write signal supply means for generating the write signal and applying the write signal to the write magnetic field generating means, and generating the microwave excitation current to generate the coplanar. Microwave-band magnetic drive comprising a microwave excitation current supply means for applying to a microwave radiator Magnetic recording / reproducing apparatus equipped with a functional thin film magnetic head.   A perpendicular magnetic recording type write head element having a main magnetic pole, an auxiliary magnetic pole, and coil means wound between the main magnetic pole and the auxiliary magnetic pole, and the write magnetic field generating means is the coil means 8. The magnetic recording / reproducing apparatus according to claim 7, wherein the even number of line conductors of the coplanar type microwave radiator are disposed between the main magnetic pole and the auxiliary magnetic pole.   9. The magnetic recording / reproducing apparatus according to claim 8, wherein the two ground conductors of the coplanar microwave radiator are constituted by the main magnetic pole and the auxiliary magnetic pole, respectively.   The phase shift means for shifting the phase of the microwave excitation current flowing through two adjacent line conductors among the even number of line conductors by 180 ° from each other is provided. 2. A magnetic recording / reproducing apparatus according to 1.   The phase-shifting means is connected to the two line conductors, respectively, and consists of two transmission lines whose line lengths are different from each other by a half wavelength of the microwave excitation current. Magnetic recording / reproducing device.   The magnetic recording / reproducing apparatus according to any one of claims 7 to 11, wherein the coplanar microwave radiator has two line conductors.   One output terminal of the microwave excitation current supply means is connected to the two line conductors via the phase shift means of the coplanar microwave radiator, and the other of the coplanar microwave excitation current supply means The magnetic recording / reproducing apparatus according to claim 11, wherein the output terminal is connected to the ground conductor via a resistor.   The magnetic recording / reproducing apparatus according to claim 7, further comprising a DC excitation current supply circuit that generates a DC excitation current and applies the DC excitation current to the coplanar microwave radiator.   At the position of the magnetic recording layer of the magnetic recording medium, the write magnetic field has a direction perpendicular or substantially perpendicular to the surface of the magnetic recording layer, and the resonance magnetic field is in the surface of the surface of the magnetic recording layer. The magnetic recording / reproducing apparatus according to claim 7, wherein the magnetic recording / reproducing apparatus is set to have a substantially in-plane direction.

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