JP2007207349A - Thin film magnetic head with near-field light generating part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin film magnetic head which surely performs writing only to a predetermined track without performing unwanted writing and erasure to adjacent tracks by an influence of a skew angle in heat assistant magnetic recording. <P>SOLUTION: The thin film magnetic head comprises: a substrate with a medium facing surface and an element forming surface perpendicular to the medium facing surface; an electromagnetic coil element for writing a data having a magnetic pole tip reaching a head edge face on the medium facing surface side; and a near-field light generating part which has a generating edge reaching the head tip face on the medium facing surface side and heats a part of a magnetic disk to write into by generating the near-field light, and provided is the thin film magnetic head in which, as a configuration on the head tip face on the medium facing surface side, the generation edge is close to the magnetic pole edge and positioned on the leading side of the magnetic pole edge, and the center line perpendicular or almost perpendicular to the track width direction of the generation edge is off the center line perpendicular or almost perpendicular to the track width direction of the magnetic pole tip. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thin film magnetic head for writing and reading a signal magnetic field, a head gimbal assembly (HGA) including the thin film magnetic head, and a magnetic disk device including the HGA. In particular, the present invention relates to a thin film magnetic head for perpendicular magnetic recording in which signals are written by using a near-field light by a heat-assisted magnetic recording method, an HGA including the thin film magnetic head, and a magnetic disk device including the HGA. .

  As the recording density of magnetic disk devices increases, further improvements in performance of thin film magnetic heads are required. As a thin film magnetic head, a composite thin film magnetic head having a structure in which a magnetoresistive (MR) effect element for reading and an electromagnetic coil element for writing are stacked is widely used. Signal data is read from and written to a magnetic disk.

  The magnetic recording medium is a so-called discontinuous body in which magnetic fine particles are aggregated, and each magnetic fine particle has a single magnetic domain structure. Here, one recording bit is composed of a plurality of magnetic fine particles. Therefore, in order to increase the recording density, the magnetic fine particles must be made smaller to reduce the irregularities at the boundaries of the recording bits. However, if the magnetic fine particles are made smaller, a decrease in the thermal stability of magnetization accompanying volume reduction becomes a problem.

A measure of the thermal stability of magnetization is given by K _U V / k _B T. Here, K _U is the magnetic anisotropy energy, V the magnetic microparticle volume of one magnetic particle, k _B the Boltzmann constant, T is the absolute temperature. Reducing the magnetic fine particles is exactly reducing V, and K _U V / k _B T is reduced as it is, and thermal stability is impaired. As a countermeasure, it is conceivable to increase the K _U simultaneously, increase in K _U results in an increase in the coercive force of the medium. On the other hand, the write magnetic field strength by the magnetic head is almost determined by the saturation magnetic flux density of the soft magnetic material constituting the magnetic pole in the head. Accordingly, when the holding force exceeds an allowable value determined from the limit of the write magnetic field strength, writing becomes impossible.

As a first method for solving the problem of the thermal stability of magnetization, a shift from the in-plane magnetic recording method to the perpendicular magnetic recording method can be considered. In the perpendicular magnetic recording medium, the recording layer thickness can be increased, and as a result, V can be increased to improve the thermal stability. As a second method, use of patterned media can be considered. In normal magnetic recording, as described above, one recording bit is composed of N magnetic fine particles and recorded, but using a patterned medium, one recording bit is set as one area of volume NV. As a result, the thermal stability index becomes K _U NV / k _B T, which is dramatically improved.

As a third method for solving the thermal stability problem, uses a large magnetic material K _U, just before the write field is applied, by applying heat to the medium, writing is performed by reducing the coercive force, the so-called A heat-assisted magnetic recording method has been proposed. This method is similar to the magneto-optical recording method, but the magneto-optical recording method gives the light spatial resolution, whereas the thermally-assisted magnetic recording method gives the magnetic field spatial resolution.

  As a conventionally proposed thermally assisted magnetic recording system, for example, in Patent Document 1, a metal scatterer having a shape such as a cone formed on a substrate and a dielectric formed around the scatterer are disclosed. A technique relating to an optical recording method using a near-field optical probe provided with a film such as a body is disclosed. Patent Document 2 discloses a technique for recording a superfine magnetic domain signal with a superfine light beam spot on a magneto-optical disk using a head using a solid immersion lens in a recording / reproducing apparatus. Further, Patent Document 3 discloses a technique for performing thermal assist by irradiating light from a built-in laser element unit to a minute optical aperture facing a medium.

In Patent Document 4, a scatterer constituting a near-field optical probe is formed in contact with the main pole of a single magnetic pole write head for perpendicular magnetic recording so that the irradiated surface is perpendicular to the recording medium. The configuration is disclosed. Further, Patent Document 5, the recording and reproducing head including a laser light source, the relationship between the width T _WW heated by the width W _W of the laser light source of the magnetic pole of the recording magnetic head is defined.

  Further, in Non-Patent Document 1, a near-field light and a magnetic field are generated using a U-shaped near-field optical probe formed on a quartz slider to form a recording pattern having a track width of about 70 nm. Technology is disclosed. Non-Patent Document 2 discloses a light heating element having a grating in which a diffraction grating that transmits light well and a diffraction grating that hardly transmits light are abutted and combined. On the other hand, as an example of using an optical fiber for introducing light, Patent Document 6 discloses a configuration in which a metal film having pinholes is provided on an end face of an optical fiber or the like cut obliquely. Patent Document 7 discloses an optical flying head provided with a movable mirror for appropriately directing laser light emitted from an optical fiber to a lens optical system.

  Among the techniques described above, a method for generating near-field light by irradiating a near-field light generating means with laser light from an optical fiber or the like, and heating the medium with this near-field light is a desired method. It is considered very promising because fine near-field light having intensity can be obtained relatively easily.

JP 2001-255254 A JP-A-10-162444 JP 2001-283404 A JP 2004-158067 A International Publication No. 01/06498 Pamphlet JP 2000-173093 A Japanese translation of PCT publication No. 2002-511176 Shintaro Miyanishi et al. “Near-field Assisted Magnetic Recording” IEEE TRANSACTIONS ON MAGNETICS, VOL.41, NO.10, pp. 2817-2821, 2005 Keiji Shono, Mitsumasa Oshiki “Current Status and Issues of Thermally Assisted Magnetic Recording” Journal of Japan Society of Applied Magnetics, VOL.29, NO.1, pages 5-13, 2005

  However, when the above-mentioned near-field light generating means is applied to a thin film magnetic head for perpendicular magnetic recording, there arises a problem that unnecessary writing or erasing may occur on adjacent tracks due to the influence of the skew angle. It was.

  In general, in a thin film magnetic head for perpendicular magnetic recording, the shape of the main pole end on the head end surface is a trapezoid having a long side on the trailing side. In other words, the side surface of the main magnetic pole tip shape is not subjected to unnecessary writing, erasing, or the like on the track adjacent to the track to be written (adjacent track) due to the influence of the skew angle generated by driving with the rotary actuator. Is beveled. However, when the near-field light generating means is applied to the thin-film magnetic head for perpendicular magnetic recording, the near-field light is affected by the skew angle depending on the position and shape of the end of the near-field light generating means on the head end face. The near-field light generated from the generating means reaches the adjacent track, and depending on the position and shape of the main magnetic pole end, unnecessary writing or erasing may be performed on the adjacent track.

In contrast, in Patent Document 5 mentioned above, tracks defines the relationship between the width T _WW heated by the width W _W of the laser light source of the magnetic pole of the recording magnetic head, a recording magnetic head and a read element The follow-up deviation with respect to is eliminated. However, this technique is not particularly intended for a thin film magnetic head for perpendicular magnetic recording having a main magnetic pole. As described above, no clear and sufficient countermeasure has been proposed for the above-mentioned specific problem that occurs when the heat-assisted magnetic recording method is applied to a thin film magnetic head for perpendicular magnetic recording.

  Accordingly, an object of the present invention is to provide a thin-film magnetic head capable of reliably writing only to a predetermined track without causing unnecessary writing or erasing to an adjacent track due to the influence of a skew angle in heat-assisted magnetic recording. And a magnetic disk drive provided with the HGA.

  Another object of the present invention is to provide a thin film magnetic head capable of applying a sufficient amount of near-field light to a predetermined position and range, an HGA including the thin film magnetic head, and a magnetic disk device including the HGA. Is to provide.

  Before describing the present invention, the terms used in the specification are defined. In the laminated structure of magnetic head elements formed on the element formation surface of the substrate, the component on the substrate side with respect to the reference layer is assumed to be “below” or “below” the reference layer, which becomes the reference It is assumed that the component on the side in the direction of stacking from the layer is “above” or “above” the reference layer.

  According to the present invention, there is provided a substrate having a medium facing surface and an element forming surface perpendicular to the medium facing surface, and a magnetic pole tip formed on the element forming surface and reaching the head end surface on the medium facing surface side. An electromagnetic coil element for writing and a generating end formed on the element forming surface and reaching the head end surface on the medium facing surface side for generating near-field light and heating a portion to be written on the magnetic disk A thin-film magnetic head provided with a near-field light generating unit, and as a configuration on the head end surface on the medium facing surface side, the generation end is close to the magnetic pole tip and is positioned on the leading side of the magnetic pole tip, A thin film magnetic head is provided in which a center line perpendicular or substantially perpendicular to the track width direction of the generation end is deviated from a center line perpendicular or substantially perpendicular to the track width direction of the magnetic pole end. Here, it is preferable that the center line of the generation end is deviated from the center line of the magnetic pole end in the direction of the outer peripheral side when facing the magnetic disk. In addition, the shape on the head end surface on the medium facing surface side of the generating end is a regular trapezoid having a short side on the trailing side, and the shape on the head end surface on the medium facing surface side of the magnetic pole end is long on the trailing side. It is preferably an inverted trapezoid having sides.

  In the thin-film magnetic head having such a configuration, the main pole layer has the width of the magnetic pole end, whether it is located on the outer peripheral track of the magnetic disk or on the inner peripheral track. It is possible to set so that the generation end of the near-field light generation unit is approximately within the track width determined by Therefore, the near-field light generated from the generation end hardly reaches the adjacent track over the inner and outer circumferences. As a result, unnecessary writing and erasing to adjacent tracks due to the influence of the skew angle of the thin film magnetic head can be prevented.

  Further, it is preferable that a waveguide section including an optical path of light irradiated on the near-field light generating section is provided, and the near-field light generating section is in contact with the end of the waveguide section on the medium facing surface side. . At this time, it is also preferable that the near-field light generating portion is a dielectric layer or a metal layer having a shape tapered toward the head end surface on the medium facing surface side.

  According to the present invention, the thin film magnetic head described above, a support mechanism for supporting the thin film magnetic head, a signal line for the electromagnetic coil element, and the thin film magnetic head comprising an MR effect element Is provided with a signal line for the MR effect element, and an HGA further provided with an optical fiber for irradiating the near-field light generating portion with light is provided.

  In this HGA, the thin film magnetic head is fixed to the support mechanism so that its center line perpendicular or substantially perpendicular to the track width direction is oblique to the longitudinal center line of the support mechanism. preferable. Further, it is preferable that the trailing side of the center line of the thin film magnetic head is directed to the outer peripheral side when facing the magnetic disk with respect to the center line of the support mechanism.

  Further, according to the present invention, at least one HGA as described above is provided, at least one magnetic disk, a light source for supplying light to the optical fiber, and a thin film magnetic field for the at least one magnetic disk. There is provided a magnetic disk device further comprising a recording / reproducing and light emission control circuit for controlling write and read operations performed by the head and controlling the light emission operation of the light source.

  According to the thin film magnetic head, the HGA including the thin film magnetic head, and the magnetic disk apparatus including the HGA according to the present invention, there is no unnecessary writing or erasing to adjacent tracks due to the influence of the skew angle in the heat assisted magnetic recording. The writing is surely performed only on a predetermined track. This makes it possible to perform a writing operation that realizes a reliable and high recording density by heat assist.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated in detail, referring an accompanying drawing. In the drawings, the same 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 disk apparatus according to the present invention.

  In the figure, reference numeral 10 denotes a magnetic disk, which is a plurality of magnetic recording media for perpendicular magnetic recording that rotates around the rotation axis of a spindle motor 11, and 12 denotes a thin film magnetic head (slider) 21 for perpendicular magnetic recording. The assembly carriage device 13 for positioning on the upper side controls the writing and reading operations of the thin film magnetic head 21 and further controls the semiconductor laser 18 which is a light source for generating a laser beam for heat assist, which will be described in detail later. The recording / reproducing and light emission control circuits are respectively shown.

  The assembly carriage device 12 is provided with a plurality of drive arms 14. These drive arms 14 can be angularly swung about a pivot bearing shaft 16 by a voice coil motor (VCM) 15 and are stacked in a direction along the shaft 16. An HGA 17 is attached to the tip of each drive arm 14. Each HGA 17 is provided with a slider 21 so as to face the surface of each magnetic disk 10. A single magnetic disk 10, drive arm 14, HGA 17, and slider 21 may be provided.

  The semiconductor laser 18 supplies laser light to the optical fiber 26, and the end cross section of the optical fiber 26 is connected to the position of its active layer by a fiber holder 19. The wavelength of the oscillation laser is, for example, 635 nm.

  FIG. 2 is a perspective view showing an embodiment of the HGA according to the present invention. 2A shows the configuration of the HGA 17 on the side facing the magnetic disk surface, and FIG. 2B shows the configuration on the side opposite to the side of the HGA 17 facing the magnetic disk surface. ing.

  As shown in FIG. 2A, the HGA 17 has a slider 21 having a magnetic head element fixed to the tip of the suspension 20, and one end of the wiring member 25 is electrically connected to the terminal electrode of the slider 21. Composed.

  The suspension 20 includes a load beam 22, a flexure 23 having elasticity fixedly supported on the load beam 22, a base plate 24 provided at the base of the load beam 22, and a lead conductor provided on the flexure 23. And the wiring member 25 which consists of the connection pad electrically connected to the both ends is comprised mainly.

  The thin film magnetic head 21 is fixed to the flexure 23 so that its center line 27 perpendicular or substantially perpendicular to the track width direction is inclined with respect to the longitudinal center line 28 of the suspension 20. Further, the trailing side 270 of the center line 27 faces the direction of the outer peripheral side when facing the magnetic disk with respect to the center line 28 of the suspension 20. By using such an oblique configuration in combination with the offset of the generation end of the near-field light generating section described later, unnecessary writing and erasing to the adjacent track due to the influence of the skew angle can be prevented.

  Referring to FIG. 2B, the HGA 17 further includes an optical fiber 26 for allowing laser light to enter from the head end face of the thin film magnetic head 21. The light output end of the optical fiber 26 is inserted into a light receiving recess 35 formed on the upper surface of the coating layer 40 provided on the element forming surface of the thin film magnetic head 21, as will be described in detail later. It is fixed with.

  It is obvious that the suspension structure in the HGA 17 of the present invention is not limited to the structure described above. Although not shown, a semiconductor laser for supplying laser light to the head driving IC chip or the optical fiber 26 may be mounted in the middle of the suspension 20.

  FIG. 3 is a perspective view showing an embodiment of a thin film magnetic head (slider) according to the present invention, which is attached to the tip of the HGA shown in FIG.

  According to FIG. 3, the thin film magnetic head 21 in this embodiment includes a slider substrate 210 having an air bearing surface (ABS) 30 that is a medium facing surface processed so as to obtain an appropriate flying height, and an ABS 30 of the slider substrate 210. Formed between the MR effect element 33 and the electromagnetic coil element 34, and the MR effect element 33 for reading signal data and the electromagnetic coil element 34 for writing signal data. A near-field light for heating the recording layer portion of the magnetic disk, which is connected to the waveguide portion 37 in contact with the end of the waveguide portion 37 and has an end reaching the head end surface 300 on the ABS side. A near-field light generating section 38; a reflecting section 36 for reflecting light from the fiber 26 and directing it toward the waveguide section 37; an MR effect element 33; an electromagnetic coil element 34; A covering layer 40 formed on the element forming surface 31 so as to cover the waveguide portion 37, the near-field light generating portion 38, and the reflecting portion 36, and an upper surface of the covering layer 40 are formed. A light receiving recess 35 for insertion and a total of four signal terminal electrodes 39 exposed from the layer surface of the covering layer 40 are provided.

  One end of the MR effect element 33 and the electromagnetic coil element 34 reaches the head end surface 300. During the writing or reading operation, the thin film magnetic head 21 floats hydrodynamically on the surface of the rotating magnetic disk with a predetermined flying height. At this time, when the element ends face the magnetic disk, reading by sensing the signal magnetic field and writing by applying the signal magnetic field are performed.

  Two signal terminal electrodes 39 are connected to each of the MR effect element 33 and the electromagnetic coil element 34. Note that the number and position of these signal terminal electrodes are not limited to the form shown in FIG. In the figure, there are four terminal electrodes. However, for example, a configuration in which three electrodes are provided and the ground is grounded to the slider substrate may be employed.

  4A is a cross-sectional view taken along the line AA of FIG. 3 schematically showing a configuration of a main part of the embodiment of the thin film magnetic head shown in FIG. 3, and FIG. 4B is a waveguide portion. 37 and FIG. 4C are plan views showing the shapes of the near-field light generator 38 on the head end surface 300. FIG.

  As shown in FIG. 4A, the MR effect element 33 includes an MR effect multilayer 332 and a lower electrode layer 330 and an upper electrode layer 334 disposed at positions sandwiching the multilayer. The MR effect multilayer 332 is a tunnel magnetoresistive (TMR) effect multilayer film in which a magnetization free layer and a magnetization fixed layer are sandwiched with a tunnel barrier layer sandwiched therebetween, a perpendicular conduction type giant magnetoresistance (CPP (Current Perpendicular to Plain) − Any one of a GMR effect multilayer film and an in-plane energization type giant magnetoresistive (CIP (Current In Plain) -GMR) effect multilayer film is provided. In either case, the signal magnetic field from the magnetic disk is sensed with very high sensitivity and reading is performed. When the MR effect multilayer 332 includes a CIP-GMR multilayer film, upper and lower shield layers are provided between the MR effect multilayer and the MR effect multilayer in place of the upper and lower electrode layers 334 and 330, respectively. In addition, an element lead conductor layer for supplying a sense current to the MR effect laminate is provided.

The lower shield layer 330 is laminated on the element formation surface 31 of the slider substrate 210 made of AlTiC (Al ₂ O ₃ —TiC) or the like. For example, NiFe, NiFeCo, CoFe having a thickness of about 0.3 μm to about 3 μm. , FeN or FeZrN. The upper shield layer 334 is made of, for example, NiFe, NiFeCo, CoFe, FeN, or FeZrN having a thickness of about 0.3 μm to about 4 μm. The reproduction gap length, which is the distance between the upper and lower shield layers 334 and 330, is about 0.02 μm to about 1 μm.

  The electromagnetic coil element 34 is for perpendicular magnetic recording, and includes a main magnetic pole layer 340, a gap layer 341, a coil layer 342, a coil insulating layer 343, and an auxiliary magnetic pole layer 344. The main magnetic pole layer 340 is a magnetic path for guiding the magnetic flux induced by the coil layer 342 while converging it to the recording layer of the magnetic disk on which writing is performed. Here, the length (thickness) in the layer thickness direction of the end portion 340a on the head end surface 300 side of the main magnetic pole layer 340 is smaller than that of the other portions. As a result, it is possible to generate a fine write magnetic field corresponding to an increase in recording density.

Here, the main magnetic pole layer 340 has, for example, a total thickness of about 0.01 μm to about 0.5 μm at the end on the ABS side, and a total thickness of other than this end is about 0.5 μm to about 3 μm. It is made of an alloy composed of any two or three of 0.0 μm Ni, Fe and Co, or an alloy to which a predetermined element is added as a main component. The gap layer 341 is made of, for example, Al ₂ O ₃ or DLC having a thickness of about 0.01 μm to about 0.5 μm. The coil layer 342 is made of, for example, Cu having a thickness of about 0.5 μm to about 3 μm. The coil insulating layer 343 is formed of, for example, a heat-cured resist layer having a thickness of about 0.1 μm to about 5 μm. The auxiliary magnetic pole layer 344 is, for example, an alloy made of any two or three of Ni, Fe and Co having a thickness of about 0.5 μm to about 5 μm, or an alloy to which a predetermined element is added with these as main components. Etc. are formed.

  The light receiving recess 35 is a dug portion formed on the upper surface of the covering layer 40 and is formed immediately above the reflecting portion 36. The light emitting end of the optical fiber 26 for emitting the laser light applied to the near-field light generating unit 38 is inserted into the light receiving recess 35 from directly above, and further fixed with an adhesive 41 such as an epoxy system. Has been. A taper is formed at the light exit end of the optical fiber 26, and the light receiving recess 35 having a tapered wall surface is fixed at a predetermined position with high accuracy with no gap. Further, the end surface of the optical fiber 26 faces or is in contact with the bottom surface 350. Here, since the diameter of the light exit end of the optical fiber 26 is about 5 μm to about 500 μm, the average inner diameter of the light receiving depression 35 is also accurately processed according to this value. The beam diameter of the laser light emitted from the light output end of the optical fiber 26 is also about 5 μm to about 500 μm.

An antireflection film 42 is formed on the bottom surface 350 of the light receiving recess 35 to reduce the amount of light that is partially reflected from the optical fiber 26 and lost. The antireflection film 42 has, for example, a single layer structure by ion-assisted vapor deposition made of Ta ₂ O ₅ or SiO ₂ or a multilayer structure by ion-assisted vapor deposition in which Ta ₂ O ₅ and SiO ₂ are alternately laminated. Yes. This single layer / multilayer structure is formed based on an optical design made in accordance with the wavelength of the incident laser beam.

  The reflection unit 36 is located immediately below the light receiving recess 35 and behind the MR effect element 33, the electromagnetic coil element 34, and the near-field light generation unit 38 when viewed from the head end surface 300. The reflective portion 36 is a metal layer such as Au, Ag, Al, Cu, or Ti, or an alloy layer of some combination thereof, and has a reflective surface 360. The reflecting surface 360 is curved so that the light from the optical fiber 26 is narrowed and incident on the end 371a of the waveguide straight line portion 371, and the laser light from the optical fiber 26 reaches the near-field light generating unit 38 as much as possible. Play a role. Thereby, the generation efficiency of near-field light improves. The reflective part 36 has a layer thickness of about 10 nm to about 500 nm, and a width in the track width direction of about 10 μm to about 500 μm. Here, the optical fiber 26 inserted into the light receiving recess 35 includes a core portion 260 and a clad portion 261 that surrounds the core portion 260. The diameter of the core part 260 is about 8 μm, for example. Since the laser light is emitted from the end of the core portion 260, the reflection surface 360 has a curved surface for appropriate reflection at least at a part of the portion directly below the core portion 260.

  The form of the reflecting portion is not limited to the above-described one, and may be, for example, a plane mirror type having a flat reflecting surface, a grating type using a diffraction grating, or a prism type.

  As described above, since the light receiving recess 35 is formed in the coating layer 40 and the optical fiber 26 is directly fixed to the thin film magnetic head, the optical path of the laser light from the optical fiber 26 is such as vibration during driving. Hardly fluctuates or shifts depending on. Therefore, according to the thin film magnetic head of the present embodiment, the positions of the light output end of the optical fiber 26 and the reflecting portion 36 and the near-field light generating portion 38 are compared with the case where the optical fiber is fixed to an external component such as a flexure. The relationship is stable, and the laser light from the optical fiber 26 can reliably and stably reach the near-field light generation unit 38 via the reflection unit 36.

  Here, both the light receiving dent 35 and the reflecting portion 36 are formed by a forming method using a thin film process to be described later. Among these, in particular, the light receiving depression 35 is formed on the upper surface of the coating layer 40 provided on the element forming surface, and therefore, the light receiving depression 35 can be formed as a series of thin film processes from the formation of the reflection portion 36. Therefore, the size and positional relationship can be set with high accuracy by a patterning technique using a photolithography method. That is, the fixed position of the light output end of the optical fiber 26 can be easily set with high accuracy. Thereby, the laser light from the optical fiber 26 can be irradiated to the near-field light generating unit 38 as designed, so that the desired near-field light generation efficiency can be obtained.

The waveguide section 37 includes an optical path from the bottom surface 350 of the light receiving depression 35 to the near-field light generating section 38 via the reflecting section 36. The waveguide section 37 is directly below the light receiving depression 35 and has a bottom surface 350 and a reflecting surface 360. Between the MR effect element 33 and the electromagnetic coil element 34 and extending substantially in parallel with the element forming surface 31, near the head end face 300. The waveguide straight portion 371 is tapered toward 300. The waveguide portion 37 is formed of a dielectric material having a refractive index n higher than that of the material forming the covering layer 40 in any portion. For example, when the coating layer 40 is made of SiO ₂ (n = 1.5), the waveguide portion 37 may be made of Al ₂ O ₃ (n = 1.63). Furthermore, when the coating layer 40 is made of Al ₂ O ₃ (n = 1.63), the waveguide section 37 has Ta ₂ O ₅ (n = 2.16), Nb ₂ O ₅ (n = 2.33), TiO (n = 2.3 to 2.55), or TiO ₂ (n = 2.3 to 2.55). By constructing the waveguide section 37 with such a material, not only the good optical characteristics of the material itself but also the total reflection conditions at the interface are adjusted, so that the propagation loss of the laser light is reduced and the near field is reduced. Light generation efficiency is improved.

  The near-field light generating unit 38 is formed of the same dielectric material as that of the waveguide unit 37, and one end is in contact with the end of the waveguide rectilinear unit 371 on the head end surface 300 side, and the other end is the head end surface 300. Has reached. According to FIG. 4B, Au, Pd, Pt, and the near-field light generating unit 38 are in contact with both sides in the track width direction of the portion of the waveguide straight portion 371 that is tapered toward the head end surface 300. A side conductor layer 43 made of a conductive material such as Rh, Ir, or an alloy made of some combination of these, or an alloy made of Al, Cu or the like added thereto is provided. With such a configuration, most of the laser light propagating through the waveguide rectilinear portion 371 through the waveguide reflecting portion 370 is concentrated on the near-field light generating portion 38 after being reflected by the reflecting surface 430 of the side conductor layer 43. To do. As a result, more laser light reaches the near-field light generation unit 38, so that the generation efficiency of the near-field light is improved.

  The width and the layer thickness in the track width direction of the near-field light generating unit 38 are sufficiently smaller than the wavelength of the incident laser light, and are about 10 nm to about 300 nm and about 10 nm to about 200 nm, respectively. When the near-field light generating unit 38 receives laser light, it is forced in the track width direction at the interface between the dielectric material which is the constituent material and the side conductor layer 43 by vibration in the track width direction of the electric field component of the laser light. An electric dipole to be oscillated is induced. The vibration of the electric dipole is almost uniform because the size of the near-field light generating unit 38 is sufficiently smaller than the wavelength of the laser light. Due to the uniform vibration of the electric dipole, an electromagnetic wave is radiated in a direction perpendicular to the vibration direction, that is, a direction toward the surface of the magnetic disk. When the electric field lines of the electromagnetic waves vibrate so that the sign of the electric dipole is switched, they are repeatedly closed and opened again to create a node and propagate. Among these, the region of the electric lines of force extending in the very vicinity from the near-field light generating unit 38 to the first node is near-field light.

  The electric field strength of this near-field light is orders of magnitude stronger than incident light, and this very strong near-field light rapidly heats the recording layer portion on the surface of the opposing magnetic disk. As a result, the coercive force of the recording layer portion is reduced to such a level that writing by a writing magnetic field is possible, so that even if a high coercive magnetic disk for high-density recording is used, writing by the electromagnetic coil element 34 is possible. It becomes. The near-field light is present in the region from the head end surface 300 to the surface of the magnetic disk up to the width or layer thickness in the track width direction of the near-field light generator 38 described above. Accordingly, in the present situation where the flying height is 10 nm or less, the near-field light sufficiently reaches the recording layer portion. Further, the width of the near-field light generated in this way is approximately the same as the above-described width or layer thickness, and the electric field intensity of the near-field light is exponentially in a region greater than this width or layer thickness. Since it attenuates, the recording layer portion of the magnetic disk can be heated very locally.

  Note that the length of the near-field light generator 38 in the direction perpendicular to the head end surface 300 is, for example, about 10 nm to about 500 nm. Further, the width of the waveguide straight portion 370 in the track width direction is, for example, about 20 μm to about 500 μm at the widest portion.

  According to FIG. 4C, as the configuration on the head end surface 300, the shape of the magnetic pole end 340b of the main magnetic pole layer 340 is a trapezoid having a long side on the trailing side (reverse trapezoid). That is, the side surface of the end portion 340a of the main magnetic pole layer 340 is provided with a bevel angle so that unnecessary writing or the like is not exerted on the adjacent track due to the influence of the skew angle generated by driving with the rotary actuator. The size of the bevel angle is, for example, about 15 degrees. Actually, the write magnetic field is mainly generated in the vicinity of the long side on the trailing side, and the application width of the write magnetic field is mainly determined by the length of the long side.

  Similarly, as a configuration on the head end surface 300, the generation end 38a of the near-field light generation unit 38 is close to the magnetic pole end 340b and is positioned on the leading side of the magnetic pole end 340b. Furthermore, the shape of the generating end 38a is a trapezoid (a regular trapezoid) having a short side on the trailing side. Here, when the center line 44 perpendicular to or substantially perpendicular to the track width direction of the generating end 38a faces the magnetic disk from the center line 45 perpendicular to or substantially perpendicular to the track width direction of the magnetic pole end 340b, the outer circumference It is shifted (offset) in parallel to the side direction. By using the configuration of the offset at the generation end of the near-field light generating unit and the configuration in which the thin film magnetic head is obliquely fixed as described above, as will be described in detail later, the adjacent due to the influence of the skew angle. Unnecessary writing and erasing to the track can be prevented.

  The near-field light generally has the strongest intensity in the vicinity of the short side on the trailing side with the narrowest width, although it depends on the wavelength of the incident laser light and the shape of the straight waveguide portion 371. That is, in the heat assist operation for heating the recording layer portion of the magnetic disk, the vicinity of the short side on the trailing side is the main heating operation portion. Therefore, according to the arrangement and shape of the generating end 38a in this embodiment, the vicinity of the short side of the generating end 38a, which is the main heating action portion, on the trailing side is very close to the magnetic pole end 340b of the main magnetic pole layer, which is the writing portion. It will be near the position. Therefore, the error in the track width direction of the set position between the generation end 38a and the magnetic pole end 340b can be extremely reduced. In addition, in an actual heat-assisted writing operation, the write magnetic field is applied immediately after the near-field light is applied to the recording layer portion of the magnetic disk from the vicinity of the short side of the generation end 38a, which is the main heating action portion. The recording layer is heated from the extreme 340b. In other words, immediately after heating the recording layer portion of the magnetic disk, it is possible to perform writing reliably with almost no gap. As a result, it is possible to prevent a write error due to an inappropriate heating portion and timing. As a result, the reliable writing operation by the heat assist is stably executed.

In addition, when the length of the short side on the trailing side at the generation end 38a is W _NF and the length of the long side on the trailing side at the magnetic pole end 340b is W _MP , the space of recording bits is used as a thermally assisted magnetic recording system. When considering that the magnetic field has a resolution, the size is set as W _NF > W _MP as the magnetic dominant. This relationship will be described in detail later.

By applying the heat-assisted magnetic recording system as described above, in fact, writing is performed on a high coercivity magnetic disk using a thin film magnetic head for perpendicular magnetic recording, and the recording bit is made extremely fine. Thus, it may be possible to achieve a recording density of ¹ Tbits / in level ² .

  Note that an inter-element shield layer 44 is formed between the MR effect element 33 and the waveguide straight portion 371 and the near-field light generator 38. The inter-element shield layer 44 plays a role of blocking the MR effect element 33 from the magnetic field generated by the electromagnetic coil element 34 and preventing external noise during reading. Further, a backing coil may be further formed between the inter-element shield layer 44 and the waveguide straight portion 371. The backing coil generates a magnetic flux that is generated from the electromagnetic coil element 34 and cancels the magnetic flux loop that passes through the upper and lower electrode layers of the MR effect element 33, thereby erasing a wide area adjacent track that is an unnecessary write or erase operation on the magnetic disk. This is intended to suppress the (WATE) phenomenon. Note that the coil layer 342 is one layer in FIG. 4A, but may be two or more layers or a helical coil.

  FIGS. 5A and 5B are a cross-sectional view and a perspective view showing another embodiment of the near-field light generating unit provided in the thin-film magnetic head according to the present invention, and FIG. FIG. 6 is a plan view showing a position and a shape on a head end surface 54 of a light generating unit 51.

  According to FIG. 5A, the waveguide portion 50 is formed between the MR effect element 52 and the electromagnetic coil element 53 as in the embodiment shown in FIG. A near-field light generator 51 is formed in contact with the end on the side. As shown in FIG. 5B, the near-field light generator 51 has a shape that tapers toward the head end surface 54, and is inclined such that the head end surface 54 side rises with respect to the element formation surface 55. And a light receiving surface 510 for receiving laser light from the optical fiber. The near-field light generating unit 51 is in contact with the end surface of the waveguide unit 50 on the medium facing surface side at the light receiving surface 510. In FIG. 5B, the waveguide section 50 and the near-field light generating section 51 are represented as perspective images viewed from the element formation surface 55 side (from the lower side) for easy viewing of the drawing. .

  The near-field light generating unit 51 is made of Au, Pd, Pt, Rh, Ir, or an alloy made of some combination of these, or an alloy containing Al, Cu, or the like added thereto. By receiving the laser beam at 510, the plasmons are excited by causing the internal free electrons to be forcibly oscillated uniformly by the electric field of the laser beam. The plasmon propagates toward the tip of the near-field light generating unit 51 on the head end face 54 side, and generates near-field light having a very strong electric field strength in the vicinity of the tip. Using this near-field light, it becomes possible to perform heat-assisted magnetic recording.

  According to FIG. 5C, on the head end face 54, the generation end 51a of the near-field light generating unit 51 is close to the magnetic pole end 530b of the main magnetic pole layer of the electromagnetic coil element 53, and leading of the magnetic pole end 530b. Located on the side. The shape of the generating end 51a is a regular trapezoid having a short side on the trailing side, and the shape of the magnetic pole end 530b is an inverted trapezoid having a long side on the trailing side. Further, the center line 56 perpendicular to or substantially perpendicular to the track width direction of the generation end 51a is located on the outer peripheral side when facing the magnetic disk from the center line 57 perpendicular to or substantially perpendicular to the track width direction of the magnetic pole end 530b. Is displaced (offset). By using the configuration of the offset at the generation end of the near-field light generating unit and the configuration in which the thin film magnetic head is obliquely fixed as described above, as will be described in detail later, the adjacent due to the influence of the skew angle. Unnecessary writing and erasing to the track can be prevented.

  Further, since the generation end 51a is close to the leading side of the magnetic pole tip 530b, an error in the track width direction of the set position between the generation end 51a and the magnetic pole end 530b can be extremely reduced. In the actual heat-assisted writing operation, the magnetic pole tip 530b of the main magnetic pole layer was reliably heated immediately after the heating operation was performed in the vicinity of the short side of the generation end 51a, which is the main heating action portion. Writing is performed on the recording layer portion. As a result, it is possible to prevent a write error due to an inappropriate heating portion and timing. As a result, the reliable writing operation by the heat assist is stably executed.

Further, when the length of the short side on the trailing side of the generating end 51a is W _NF ′ and the length of the long side on the trailing side of the magnetic pole end 530b is W _MP ′, the recording bit is used as the thermally assisted magnetic recording method. When the magnetic field is considered to have a spatial resolution, the size is set such that W _NF ′> W _MP ′ as the magnetic dominant.

  FIG. 6 is a schematic diagram of the head end surface on the medium facing surface side, showing various modifications regarding the shape of the generating end of the near-field light generating portion.

Hereinafter, using the modification of FIG. 6 (A) ~ (C) , illustrating the relationship between the length W _MP of the long sides of length W _NF and pole tip of the short side of the generating end. In general, magnetic recording systems using near-field light are roughly classified into two types: magnetic dominant recording and thermal dominant recording. For magnetic dominant recording, than the width of a region for applying a write magnetic field in the recording layer of the magnetic disk (magnetic field applying width) is set large width (heating length) for heating up sufficiently reduce the holding force H _C . That is, the write width (track width) is equivalent to the magnetic field application width. In this case, W _NF > W _MP is set. In contrast, in the case of thermal dominant recording, the heating width is set to be equal to or narrower than the magnetic field application width. That is, the writing width (track width) is equivalent to the heating width. In this case, W _NF ≦ W _MP is set.

When the magnetic field has the spatial resolution of the recording bit as the heat-assisted magnetic recording method, W _NF > W _MP as the magnetic dominant as in the embodiment shown in FIGS. 4 (C) and 5 (C). Is required.

On the other hand, FIG. 6A shows the case of thermal dominant recording, where the length of the short side on the trailing side at the generating end 60 of the near-field light generating unit is W _NF1 and the trailing at the magnetic pole end 61 is performed. When the length of the long side on the side is W _MP1 , W _NF1 <W _MP1 is set. Furthermore, as shown in FIG. 6 (B), similarly in the case of thermal dominant recording, the shape of the generation end 65 has one apex angle on the trailing side and has a base on the leading side. It is a triangle. In this case, the vicinity of one apex on the trailing side becomes a main heating action portion, so that a very fine recording bit can be formed. In the case where the shape of the generating end is a triangle, it is considered that the trapezoidal shape is the limit where the short side is shortened.

  6A and 6B, the center line 63 of the generation end 60 and the center line 68 of the generation end 65 are the center line 64 of the magnetic pole end 61 and the center line of the magnetic pole end 66, respectively. 69 is offset (offset) in the direction of the outer periphery when facing the magnetic disk. By using the configuration of the offset at the generation end of the near-field light generating unit and the configuration in which the thin film magnetic head is obliquely fixed as described above, as will be described in detail later, the adjacent due to the influence of the skew angle. Unnecessary writing and erasing to the track can be prevented.

  In addition, as described above, the shape of the generation end of the near-field light generating unit is a regular trapezoid having a short side on the trailing side, and the length of the short side is set to the length of the long side of the magnetic pole end. By adjusting with respect to this, the thin film magnetic head can be applied to the magnetic dominant recording system and the thermal dominant recording system in an appropriate form in combination with the recording medium. Here, the shape of the trapezoidal shape is a well-known technique for forming an Abbotted Junction structure for bias application in a CPP-GMR effect element, as will be described in detail later with reference to FIG. By applying, it can be reliably formed with high accuracy. As a result, the length of the short side of the near-field light generator can be set with a predetermined accuracy.

  FIG. 7 is a schematic diagram for explaining the operational effects of the offset configuration at the generation end of the near-field light generating unit and the configuration in which the thin-film magnetic head is obliquely fixed according to the present invention.

The thin film magnetic head 21, the center line 44 of the generation end 38a of the near-field light generation portion, from the center line 45 of the pole end 340b of the main magnetic pole layer, (is offset) are shifted by a distance D _OFF on the outer peripheral side . Further, the center line 27 of the thin-film magnetic head, relative to the center line 28 of the suspension 20, are oblique angle theta _H. At this time, the direction of the angle theta _H is a direction toward the outer circumferential side. In the figure, the angle formed by the longitudinal direction of the thin film magnetic head and the tangential direction of the track is a skew angle θ _SKEW .

  In the thin-film magnetic head 21 shown in FIG. 7 having such a configuration, the tray of the magnetic pole tip 340b is placed on the outer track 700 and the inner track 701. The generation end 38a of the near-field light generating part is approximately within the track width mainly determined by the long side on the ring side. In particular, the short side on the trailing side, which is the main heat assisting action portion, can be reliably accommodated within the track width. Therefore, the near-field light generated from the generation end 38a hardly reaches the adjacent track over the inner and outer circumferences. As a result, unnecessary writing and erasing to adjacent tracks due to the influence of the skew angle of the thin film magnetic head can be prevented.

Actually, the distance D _OFF , the angle θ _H , the distance D _N−W between the short side of the generating end 38a and the long side of the magnetic pole end 340b, and the position of the pivot bearing shaft 16 are matched to the distribution of the skew angle θ _SKEW. etc. was adjusted to a holding force H _C of adjacent tracks can be made heat of the grade which is not less than a predetermined value as the allowable limit, secured to diagonal offset structure and a thin film magnetic head of generating end of the near-field light generating unit Determined configuration is determined.

  FIG. 8 is a cross-sectional view for explaining an embodiment of a method for forming a light receiving depression and a reflection portion of a thin film magnetic head according to the present invention.

First, as shown in FIG. 8A, a dielectric film 71 such as Al ₂ O ₃ that becomes a base of the reflecting portion is formed on the slider substrate 210 by, for example, a sputtering method. A resist pattern 72 is formed. Next, using this resist pattern 72 as a mask, etching is performed using an ion milling method or the like to form a base having a reflective surface shape. At the time of this formation, as shown in FIG. 8B1, the incidence of milling Ar ions 73 is at a high angle with respect to the element formation surface 31, that is, close to the normal direction of the element formation surface 31. When set, a base having a steeper curved surface is formed. On the other hand, as shown in FIG. 8 (B2), when the Ar ions 74 are incident at a low angle with respect to the element formation surface 31, that is, closer to the direction in the element formation surface 31, A base having a gently curved surface is formed. Therefore, it is possible to form a reflecting surface having a designed curvature distribution by adjusting the incident angle of Ar ions during the ion milling.

Next, as shown in FIG. 8C, a metal layer such as Au or an alloy layer thereof is laminated on the curved surface of the base 75 of the formed reflecting portion by, for example, a sputtering method or an ion beam deposition method. The reflection part 36 is formed. Next, as shown in FIG. 8D, a dielectric film such as TiO ₂ having a predetermined refractive index is laminated by, for example, sputtering or ion beam deposition, and the resist pattern 72 is removed by lift-off. Thus, the waveguide portion 37 is formed. Thereafter, an antireflection film 42 is formed on the upper surface of the waveguide reflection portion of the waveguide portion 37 by, for example, ion-assisted vapor deposition. Next, the coating layer 40 is laminated by, for example, a sputtering method so as to cover the waveguide portion 37 and the antireflection film 42. Thereafter, as shown in FIG. 8E, the light-receiving depressions 35 are formed by etching the upper surface of the coating layer 40 using a wet etching method or a reactive ion etching (RIE) method. Through the above steps, the light receiving depression 35 and the reflecting portion 36 immediately below the light receiving depression 35 are accurately formed as a series of thin film processes.

  9A and 9B are a plan view and a cross-sectional view illustrating an embodiment of a method for forming the tapered portion of the straight waveguide portion and the near-field light generating portion. 9A2 to 9E2 respectively represent cross sections taken along the lines aa to ee of FIGS. 9A1 to 9E1.

9A and 9A, first, a dielectric film 81 such as TiO ₂ having a refractive index higher than that of the base, which is a near-field light generating unit, is formed on the base 80 of Al ₂ O ₃ or the like. A film is formed, and a resist pattern 82 for lift-off is formed thereon. Next, as shown in FIGS. 9B1 and 9B2, unnecessary portions of the dielectric film 81 are removed using an ion milling method or the like except for the portion immediately below the resist pattern 82. Thereafter, as shown in FIGS. 9C1 and 9C2, a conductive film 83 such as Au serving as a side conductor layer is formed by using a sputtering method or the like. Thereafter, the resist pattern 82 and the conductive film thereon are formed. The film is removed by so-called lift-off. Thereafter, as shown in FIGS. 9D1 and 9D2, after the resist pattern 84 is formed, the dielectric film 81 and the conductive film 83 are removed by using an ion milling method or the like except under the resist pattern 84. Remove unnecessary parts. Next, as shown in FIGS. 9E1 and 9E2, a backfill dielectric film 85 made of the same dielectric material as the dielectric film 81 is formed by sputtering or the like. Thereafter, the resist pattern 84 and the dielectric film thereon are removed by so-called lift-off. In the subsequent MR height process, the portion on the left side of the ff line in FIG. 9 (E2) is ground so that the ff line in FIG. 9 (E2) becomes the head end surface on the ABS side. , The right side of the ff line is the near-field light generating part of the thin film magnetic head.

By repeating the above steps, as shown in FIG. 9F, the near-field light generating portion 38, the waveguide layer 86 made of the backfill dielectric film 85, the waveguide layer 87 formed thereafter, Sequentially increasing waveguide layers can be formed continuously. These waveguide layers constitute a tapered end portion of the straight waveguide portion. Further, similarly to the base 80, a cover dielectric film 88 made of a material such as Al ₂ O ₃ having a refractive index smaller than that of the material constituting the waveguide layer is formed. Here, the thickness of the near-field light generator 38 is, for example, about 30 nm, the thickness of the waveguide layer 86 is, for example, about 60 nm, and the thickness of the waveguide layer 87 is, for example, about 300 nm. It is. Further, the thickness of the base 80 and the cover dielectric film 88 is, for example, about 60 nm.

  FIG. 10 is a block diagram showing a circuit configuration of the recording / reproducing and light emission control circuit 13 of the magnetic disk apparatus shown in FIG.

  In FIG. 10, 90 is a control LSI, 91 is a write gate that receives recording data from the control LSI 90, 92 is a write circuit, 93 is a ROM that stores a control table for operating current values supplied to the semiconductor laser 18, etc. Is a constant current circuit that supplies a sense current to the MR effect element 33, 96 is an amplifier that amplifies the output voltage of the MR effect element 33, 97 is a demodulation circuit that outputs reproduction data to the control LSI 90, and 98 is a temperature. A detector 99 indicates a control circuit for the semiconductor laser 18.

  The recording data output from the control LSI 90 is supplied to the write gate 91. The write gate 91 supplies recording data to the write circuit 92 only when a recording control signal output from the control LSI 90 instructs a writing operation. The write circuit 92 causes a write current to flow through the coil layer 342 in accordance with the recording data, and the electromagnetic coil element 34 performs writing on the magnetic disk.

  A constant current flows from the constant current circuit 95 to the MR multilayer 332 only when the reproduction control signal output from the control LSI 90 instructs a read operation. The signal reproduced by the MR effect element 33 is amplified by the amplifier 96 and then demodulated by the demodulation circuit 97, and the obtained reproduction data is output to the control LSI 90.

  The laser control circuit 99 receives a laser ON / OFF signal and an operating current control signal output from the control LSI 90. When this laser ON / OFF signal is an on operation instruction, an operating current equal to or higher than the oscillation threshold is applied to the semiconductor laser. The operating current value at this time is controlled to a value corresponding to the operating current control signal. The control LSI 90 generates a laser ON / OFF signal according to the timing of the recording / reproducing operation, and takes into account the temperature measurement values of the recording layer of the magnetic disk and the semiconductor laser 18 by the temperature detector 98, and the like, and controls the ROM 93. The value of the operating current value control signal is determined based on the table. Here, the control table shows not only the temperature dependence of the oscillation threshold value and the light output-operating current characteristic, but also the relationship between the operating current value and the temperature rise of the recording layer subjected to the heat assist action, and the coercive force. Includes data on temperature dependence. In this way, by providing the laser ON / OFF signal and the operating current value control signal system independently of the recording / reproducing operation control signal system, not only the energization to the semiconductor laser simply linked to the recording operation, More various energization modes can be realized.

  It is apparent that the circuit configuration of the recording / reproducing and light emission control circuit 13 is not limited to that shown in FIG. The write operation and the read operation may be specified by a signal other than the recording control signal and the reproduction control signal. In addition, it is desirable to energize the semiconductor laser 18 at least during or immediately before the write operation, but it is also possible to energize for a predetermined period in the sequence of the write operation and the read operation.

  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 disk device according to the present invention. FIG. It is a perspective view which shows one Embodiment of HGA by this invention. FIG. 3 is a perspective view showing a first embodiment of a thin film magnetic head according to the present invention, which is attached to the tip of the HGA shown in FIG. 2. 3 is a cross-sectional view taken along the line AA in FIG. 3 schematically showing the configuration of the main part of the embodiment of the thin film magnetic head shown in FIG. 3, and a plan view showing the shapes of the waveguide part and near-field light generating part, and It is a top view which shows the shape in the head end surface of a light generation part. It is sectional drawing and perspective view which show other embodiment of the near-field light generation part with which the thin film magnetic head by this invention is provided, and the top view which shows the position and shape in the head end surface of a near-field light generation part. It is the schematic of the head end surface by the side of a medium opposing surface which shows the various changes about the shape of the generation | occurrence | production end of a near-field light generation part. It is the schematic for demonstrating the effect of the offset structure in the generation | occurrence | production end of a near-field light generation part and the structure fixed diagonally of the thin film magnetic head by this invention. It is sectional drawing explaining one Embodiment of the formation method of the light reception hollow and reflection part of the thin film magnetic head by this invention. It is the top view and sectional drawing explaining one Embodiment of the formation method of the taper part and the near field light generation part of a waveguide straight advance part. FIG. 2 is a block diagram showing a circuit configuration of a recording / reproducing and light emission control circuit of the magnetic disk device shown in FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Magnetic disk 11 Spindle motor 12 Assembly carriage apparatus 13 Recording / reproduction | regeneration and light emission control circuit 14 Drive arm 15 Voice coil motor (VCM)
16 Pivot bearing shaft 17 Head gimbal assembly (HGA)
DESCRIPTION OF SYMBOLS 18 Semiconductor laser 19 Fiber holder 20 Suspension 21 Slider 210 Slider substrate 22 Load beam 23 Flexure 24 Base plate 25 Wiring member 26 Optical fiber 260 Core part 261 Clad part 27, 28, 44, 45, 56, 57, 63, 64 Center line 270 Trailing part of center line 30 Air bearing surface (ABS)
300, 54 Head end surface 31, 55 Element formation surface 33, 52 MR effect element 330 Lower electrode layer 332 MR effect laminate 334 Upper electrode layer 34, 53 Electromagnetic coil element 340 Main magnetic pole layer 340a End part 340b, 530b, 61, 66 Magnetic pole end 341 Gap layer 342 Coil layer 343 Coil insulating layer 344 Auxiliary magnetic pole layer 344a, 62, 67 End 35, 35 'Light receiving recess 350 Bottom surface 36, 36' Reflecting portion 360 Reflecting layer 37, 37 ', 50 Waveguide portion 370 Conductor Waveguide reflection portion 371 Waveguide rectilinear portion 38, 38 ', 51 Near-field light generation portion 38a, 51a, 60, 65 Generation end 39 Signal terminal electrode 40, 40' Cover layer 41 Adhesive 42 Antireflection film 43 Side conductor layer 44 Inter-element shield layer 510 Light-receiving surface 700, 701 Track 71 Dielectric film 72 Resist Str pattern 73, 74 Ar ion 75 Base 80 Base 81 Dielectric film 82, 84 Resist pattern 83 Conductive film 84 Magnetic layer 85 Backfill dielectric film 86, 87 Waveguide layer 88 Cover dielectric film 90 Control LSI
91 Write gate 92 Write circuit 93 ROM
95 constant current circuit 96 amplifier 97 demodulation circuit 98 temperature detector 99 laser control circuit

Claims (9)

An electromagnetic coil for data writing having a medium facing surface and a substrate having an element forming surface perpendicular to the medium facing surface, and a magnetic pole tip formed on the element forming surface and reaching a head end surface on the medium facing surface side Near-field light generation for heating a portion to be written on a magnetic disk by generating near-field light having an element and a generation end formed on the element formation surface and reaching the head end surface on the medium facing surface side A thin film magnetic head comprising:
As a configuration on the head end surface on the medium facing surface side, the generation end is located close to the magnetic pole end and positioned on the leading side of the magnetic pole end, and is perpendicular or substantially perpendicular to the track width direction of the generation end. The thin film magnetic head is characterized in that the center line is deviated from the center line perpendicular or substantially perpendicular to the track width direction of the magnetic pole end.   2. The thin film magnetic head according to claim 1, wherein the center line of the generation end is shifted from the center line of the magnetic pole end in a direction toward an outer peripheral side when facing the magnetic disk.   The shape of the generating end on the head end surface on the medium facing surface side is a regular trapezoid having a short side on the trailing side, and the shape of the magnetic pole end on the head end surface on the medium facing surface side is the trailing side. 3. The thin film magnetic head according to claim 1, wherein the thin film magnetic head is an inverted trapezoid having a long side.   A waveguide section including an optical path of light applied to the near-field light generating section is provided, and the near-field light generating section is in contact with the end of the waveguide section on the medium facing surface side. The thin film magnetic head according to claim 1, wherein the thin film magnetic head is a magnetic head.   5. The thin film magnetic head according to claim 4, wherein the near-field light generating portion is a dielectric layer or a metal layer having a shape tapered toward a head end surface on the medium facing surface side.   6. The thin film magnetic head according to claim 1, a support mechanism for supporting the thin film magnetic head, a signal line for the electromagnetic coil element, and the thin film magnetic head having a magnetoresistive effect. A head gimbal comprising an optical fiber for irradiating the near-field light generating part with a signal line for the magnetoresistive effect element when the element is provided. assembly.   The thin film magnetic head is fixed to the support mechanism so that its center line perpendicular or substantially perpendicular to the track width direction is inclined with respect to the longitudinal center line of the support mechanism. The head gimbal assembly according to claim 6.   8. The trailing side of the center line of the thin film magnetic head is directed to a direction that becomes an outer peripheral side when facing the magnetic disk with respect to the center line of the support mechanism. Head gimbal assembly.   9. At least one head gimbal assembly according to any one of claims 6 to 8, comprising at least one magnetic disk, a light source for supplying light to the optical fiber, and the at least one magnetic disk And a recording / reproducing and light emission control circuit for controlling the writing and reading operations performed by the thin film magnetic head and controlling the light emitting operation of the light source.

Images