JP2007200475A - Thin film magnetic head provided with light receiving hollow and near-field light generating part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin film magnetic head wherein a near-field light generating means can be reliably and stably irradiated with light by using an optical fiber and a fixing position of an end of the optical fiber can be easily and accurately decided in a constitution wherein an element forming surface and a medium facing surface are orthogonal to each other. <P>SOLUTION: The thin film magnetic head is provided with a substrate having the medium facing surface and the element forming surface vertical to the medium facing surface, a electromagnetic coil element for writing data formed on the element forming surface, a near-field light generating part generating near-field light for heating a magnetic recording medium at the time of writing and a covering layer formed on the element forming surface so as to cover the electromagnetic coil element and the near-field light generating part, wherein a light receiving hollow in which the end of the optical fiber can be inserted is formed on the upper surface of the covering layer, and a reflection part for reflecting light from the optical fiber toward the near-field light generating part is provided at the upper part of the element forming surface and at a directly under part of the light receiving hollow. <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, 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. Furthermore, 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.

  Furthermore, as an example of using an optical fiber for introducing light, Patent Document 5 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. Furthermore, Patent Document 6 discloses an optical flying head including a movable mirror for appropriately directing laser light emitted from an optical fiber to a lens optical system. Based on such a technique, a method of generating a near-field light by irradiating a laser emitted from an optical fiber to a means for generating a near-field light, and heating the medium by the near-field light is a semiconductor laser. Such a complicated structure is not required to be formed inside the head, and fine near-field light having a desired intensity can be obtained relatively easily, which is considered very promising.

JP 2001-255254 A JP-A-10-162444 JP 2001-283404 A JP 2004-158067 A 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 an optical fiber is used for introducing light, there has been a problem that it is difficult to reliably and stably irradiate light to the near-field light generating means. Furthermore, there has been a problem that it is difficult to accurately determine the fixed position of the optical fiber end.

  Actually, the near-field light generating means naturally faces the head end face facing the magnetic recording medium in order to heat the magnetic recording medium. Further, the near-field light generating means needs to be provided close to the magnetic head element for writing and reading signal data, and further, the light receiving surface cannot be formed so large from the principle of generating near-field light. Therefore, when the light emitted from the optical fiber is irradiated from a position separated from the head end surface facing the magnetic recording medium, the light is reliably and stably applied to the light receiving surface of the near-field light generating means by the vibration of the head during driving. It is difficult to irradiate light.

  Furthermore, in order to irradiate the light receiving surface of the very fine near-field light generating means, it is necessary to fix the light emitting end of the optical fiber at an appropriate position with very high accuracy. In the formed thin film magnetic head, it is very difficult to determine the fixed position.

  For example, it is conceivable to deal with these problems by using the movable mirror described in Patent Document 6 so that incident light is appropriately directed to the near-field light generating means as needed. However, in order to form such a movable mirror by microfabrication, many and complicated processes are required, and further, a power source and a circuit for driving are also required.

  Further, according to the technique described in Non-Patent Document 1, light can be incident without using a mirror in a state where the light source is away from the medium surface. However, this technology is premised on a configuration in which the integration surface of the near-field light generating means and the medium facing surface are parallel to each other. What is the configuration of a general thin film magnetic head in which the element formation surface and the medium facing surface are orthogonal to each other? It is completely different and the affinity is not good. That is, for example, it is very difficult to apply to a thin film magnetic head for perpendicular magnetic recording.

  Furthermore, when the light from the optical fiber is irradiated from a position sufficiently away from the head end surface facing the magnetic recording medium, when propagating through the overcoat layer such as alumina, vacancies, impurities in the overcoat layer, The loss of light due to the presence of a heterogeneous phase increases, and the induction efficiency of electric dipole vibration, and hence the generation efficiency of near-field light, is unavoidable.

  Accordingly, an object of the present invention is to reliably irradiate light to the near-field light generating means using an optical fiber in a configuration in which the element formation surface and the medium facing surface are orthogonal to each other. An object of the present invention is to provide a thin film magnetic head capable of easily and accurately determining the fixed position of the fiber end, an HGA including the thin film magnetic head, and a magnetic disk device including the HGA.

  Another object of the present invention is to provide a thin film magnetic head with low incident light loss and high near-field light generation efficiency, an HGA including the thin film magnetic head, and a magnetic disk device including the HGA. is there.

  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, a substrate having a medium facing surface and an element forming surface perpendicular to the medium facing surface, and data writing formed on the element forming surface and having an end reaching the head end surface on the medium facing surface side. An electromagnetic coil element, a near-field light generating part having an end reaching the head end surface on the medium facing surface side for generating a near-field light and heating the magnetic recording medium at the time of writing. A thin film magnetic head provided with a coating layer formed on the element forming surface so as to cover the coil element and the near-field light generating part,
On the upper surface of the covering layer, a light receiving depression is formed, into which an end of an optical fiber for irradiating light to the near-field light generating portion can be inserted, and is located above the element formation surface and directly below the light receiving depression. There is provided a thin film magnetic head provided with a reflection part for reflecting light from an optical fiber and directing the light toward a near-field light generation part.

  As described above, since the light receiving depression is formed in the covering layer, the light output end of the optical fiber is inserted into the light receiving depression and directly fixed to the thin film magnetic head. Therefore, the optical path of the light from the optical fiber hardly fluctuates or shifts due to vibration during driving. As a result, the light from the optical fiber can reliably reach the near-field light generation unit via the reflection unit.

  In addition, both the light receiving depression and the reflection portion are formed by a forming method using a thin film process. In particular, since the light receiving depression is formed on the upper surface of the coating layer provided on the element forming surface, the light receiving depression can be formed as a series of thin film processes from the formation of the reflecting portion. 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 can be easily set with high accuracy. As a result, the near-field light generator can be irradiated with the laser light from the optical fiber as designed, so that the desired near-field light generation efficiency can be obtained.

  Here, in the thin film magnetic head according to the present invention, an MR effect element for reading data having an end reaching the head end surface on the medium facing surface side is further provided on the element forming surface, and the near-field light generating portion is The reflector is located between the MR effect element and the electromagnetic coil element, and the reflection part is located behind the MR effect element, the near-field light generating part, and the electromagnetic coil element as seen from the head end surface on the medium facing surface side. It is also preferable. At this time, the waveguide section including the optical path from the bottom surface of the light receiving depression to the near-field light generating section through the reflecting section is formed from a material having a higher refractive index than the material forming the coating layer. Is preferred.

  Alternatively, an MR effect element for reading data having an end reaching the head end surface on the medium facing surface side is further formed on the element forming surface, and the near-field light generating unit includes the MR effect element, the electromagnetic coil element, It is also preferable that the reflecting portion is located obliquely behind the near-field light generating portion when viewed from the head end surface on the medium facing surface side. At this time, the waveguide section including the optical path from the bottom surface of the light receiving depression to the near-field light generating section through the reflecting section is formed from a material having a higher refractive index than the material forming the coating layer. Is preferred.

  With such a configuration, when the waveguide portion and the reflection portion are formed, the size limitation by the MR effect element and the electromagnetic coil element 34 is reduced, so that the size design margin is increased. In particular, the design freedom of the height (thickness) in the stacking direction of the waveguide portion is increased, so that more light can be propagated to the near-field light generating portion, and the generation efficiency of near-field light is further improved. Can be improved.

  In addition, the waveguide portion is tapered toward the head end surface in the vicinity of the head end surface on the medium facing surface side, and the near-field light generating portion is formed of the same material as that for forming the waveguide portion. The side conductor layer made of a conductive material is in contact with the taper portion of the waveguide portion and both sides of the near-field light generating portion in the track width direction. Is preferred.

  Further, the electromagnetic coil element has a main magnetic pole for generating a write magnetic field, and the end of the near-field light generating unit that reaches the head end surface on the medium facing surface side is the head on the medium facing surface side of the main magnetic pole. It is preferable to be close to the end that has reached the end face.

  Furthermore, it is preferable that the reflection portion is a reflection layer having a reflection surface that is curved so as to restrict light from the optical fiber. It is also preferable that a single-layer or multilayer antireflection film is formed on the bottom surface of the light-receiving depression.

  According to the present invention, furthermore, the above-described thin film magnetic head, a support mechanism for supporting the thin film magnetic head, a signal line for the electromagnetic coil element, and the thin film magnetic head provided with an MR effect element There is provided an HGA further comprising an optical fiber including a signal line for the MR effect element and having one end inserted into and fixed to the light receiving recess.

  According to the present invention, furthermore, at least one HGA as described above is provided, at least one magnetic recording medium, a light source for supplying light to the optical fiber, and the at least one magnetic recording medium. 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 thin film magnetic head and controlling a light emission operation of a light source.

  According to the thin-film magnetic head, the HGA including the thin-film magnetic head, and the magnetic disk device including the HGA according to the present invention, the near-field light generating means can be reliably used in the configuration in which the element formation surface and the medium facing surface are orthogonal to each other. Light can be irradiated stably. Furthermore, it is possible to easily determine the fixed position of the optical fiber end with high accuracy. Moreover, the loss of incident light is reduced, and the generation efficiency of near-field light is improved. Thereby, for example, in a thin film magnetic head for perpendicular magnetic recording, it is possible to realize highly reliable and efficient heat-assisted magnetic recording.

  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 first 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.

  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 a first 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 the first 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 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 the signal data and the electromagnetic coil element 34 for writing the signal data. Near-field light for heating the recording layer portion of the magnetic disk, which is connected in contact with the end of the waveguide portion 37 and has an end that reaches the head end surface 300 on the ABS side. A near-field light generating section 38 to be generated; a reflecting section 36 for reflecting light from the fiber 26 to be directed to the waveguide section 37; an MR effect element 33; and an electromagnetic coil element 3 A coating layer 40 formed on the element forming surface 31 so as to cover the waveguide section 37, the near-field light generating section 38, and the reflection section 36, and the light output from the optical fiber 26. A light receiving recess 35 for inserting the end 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 the configuration of the main part of the first embodiment of the thin film magnetic head shown in FIG. 3, and FIG. FIG. 4C is a plan view illustrating the shapes of the waveguide section 37 and the near-field light generating section 38, and FIG. 4C is a plan view illustrating the shapes of the near-field light generating section 38 on the head end surface 300.

  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 invention, the positional relationship between the light receiving dent 35 and the reflecting portion 36 is more stable than when the optical fiber is fixed to an external component such as a flexure, and the laser beam from the optical fiber 26 is stabilized. It is possible to reliably reach the near-field light generator 38 through the reflector 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. Here, in particular, since the light receiving depression 35 is formed on the upper surface of the coating layer 40 provided on the element formation surface, the light receiving depression 35 can be formed as a series of thin film processes from the formation of the reflecting 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 extends substantially parallel to the element forming surface 31, but in the vicinity of the head end surface 300. The waveguide straight portion 371 is tapered toward the head end surface 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 that of incident light, and this very strong near-field light rapidly heats the opposing local portion of the magnetic disk surface. As a result, the coercive force of this local portion is reduced to a size that allows writing by a write magnetic field, so that even if a high coercivity magnetic disk for high-density recording is used, writing by the electromagnetic coil element 34 is possible. Become. 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, on the head end surface 300, the generation end 38a of the near-field light generation unit 38 is close to the end 340b of the main magnetic pole layer 340 of the electromagnetic coil element 34, and the leading side of the end 340b. Is located. The shape of the generating end 38a is a regular trapezoid having a short side on the trailing side.

  Here, 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. When the shape of the generating end 38a is, for example, a triangle having a base on the leading side and one apex angle on the trailing side, the vicinity of one apex on the trailing side is the main heating action. Part.

  The shape of the end 340b of the main magnetic pole layer 340 is an inverted trapezoid having a long side on the trailing side. 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 width of the write track is determined by the length of the long side.

  According to the arrangement and shape of the generating end 38a of the near-field light generating unit 38 and the end 340b of the main magnetic pole layer 340 described above, the vicinity of the short side on the trailing side of the generating end 38a that is a main heating action portion. However, since it is at a position very close to the end 340b of the main magnetic pole layer, which is the writing portion, immediately after the heat is applied to the recording layer portion of the magnetic disk, the writing magnetic field can be applied with almost no gap. As a result, a stable writing operation by heat assist can be surely executed.

Here, the relationship between the length W _NF of the trailing side at the generation end 38 a of the near-field light generation unit 38 and the length W _MP of the long side at the trailing side at the end 340 b of the main magnetic pole layer 340 is expressed as follows. Consider.

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 a spatial resolution of recording bits as a heat-assisted magnetic recording system, W _NF > W _MP is required as a magnetic dominant.

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.

  FIG. 5 is a perspective view showing a second 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. 5A, in the thin film magnetic head 21 ′ according to the second embodiment, the components other than the light receiving recess 35 ′, the reflecting portion 36 ′, the waveguide portion 37 ′, and the near-field light generating portion 38 ′. The position and the function of each component are the same as those in the first embodiment shown in FIG.

As in the first embodiment, the reflecting portion 36 ′ is provided directly below the light receiving recess 35 ′, but is located obliquely behind the near-field light generating portion 38 ′ when viewed from the head end surface 300. The waveguide section 37 'includes an optical path from which the laser light from the optical fiber reaches the near-field light generating section 38' via the reflecting section 36 '. The head end surface 300 starts from the near-field light generating section 38'. Is formed in a region inclined in the track width direction from the center line 50 'of the head which is perpendicular to the head. Accordingly, the light receiving recess 35 'is provided at a position shifted from the center line 50' on the upper surface of the coating layer 40 '. Also in this embodiment, side conductor layers as shown in FIGS. 4B and 4C are provided on both ends of the waveguide portion 37 ′ and the near-field light generating portion 38 ′ in the track width direction. It is preferable to be provided. With such a configuration, when the waveguide portion 37 ′ and the reflection portion 36 ′ are formed, the size limitation by the MR effect element 33 and the electromagnetic coil element 34 is reduced, so that the size design margin is increased. In particular, as shown in FIG. 5B, the degree of freedom in design of the height (thickness) _TWG in the stacking direction of the waveguide portion 37 ′ is increased, so that more light is transmitted to the near-field light generating portion 38. ′, And the generation efficiency of near-field light can be further improved.

  FIG. 6 is a cross-sectional view and a perspective view showing various modifications of the waveguide section and the near-field light generating section provided in the thin film magnetic head according to the present invention.

  According to FIG. 6 (A1), the waveguide section 60 is formed between the MR effect element 62 and the electromagnetic coil element 63 as in the first embodiment shown in FIG. A near-field light generator 61 is formed in contact with the end on the head end face 64 side. As shown in FIG. 6A2, the near-field light generator 61 has a shape that tapers toward the head end surface 64, and is inclined such that the head end surface 64 side rises with respect to the element forming surface 65. And a light receiving surface 610 for receiving laser light from the optical fiber. In FIG. 6A2, the waveguide section 60 and the near-field light generating section 61 are represented as perspective images viewed from the element formation surface 65 side (from the lower side) for easy viewing of the drawing. . The near-field light generating unit 61 is made of Au, Pd, Pt, Rh or Ir, or an alloy made of some combination of these, or an alloy of which Al, Cu or the like is added, etc. By receiving laser light at 610, plasmons are excited by the internal free electrons being forced to vibrate uniformly by the electric field of the laser light. The plasmon propagates toward the tip of the near-field light generating unit 61 on the head end face 64 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. 6B, the waveguide section 67 and the near-field light generating section 68 have the same structure as that of the first embodiment shown in FIG. Located above. The main magnetic pole layer 691 of the electromagnetic coil element 69 is provided on the leading side of the auxiliary magnetic pole layer 690, and the end 68 a on the head end surface 70 side of the near-field light generating unit 68 is the head end surface 70 of the main magnetic pole layer 691. It is close to the side end 691a and is located on the trailing side of the end 691a. The reflection part 66 is located behind the waveguide part 67 as viewed from the head end face 70, reflects light from the optical fiber and makes it incident on the waveguide part 67. Even in such a configuration, near-field light having a very strong electric field strength can be generated in the vicinity of the end 68a of the near-field light generating unit 68, so that heat-assisted magnetic recording is performed using the near-field light. Is possible.

  FIG. 7 is a cross-sectional view for explaining an embodiment of a method for forming a light receiving recess and a reflecting portion of a thin film magnetic head according to the present invention.

First, as shown in FIG. 7A, on the slider substrate 210, a dielectric film 71 such as Al ₂ O ₃ serving as a base of the reflecting portion is formed 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. 7B1, 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. 7 (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. 7C, 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. 7D, 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. 7E, the light-receiving depression 35 is 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.

  FIGS. 8A and 8B 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. 8 (A2) to (E2) represent cross sections taken along lines aa to ee of FIGS. 8 (A1) to (E1), respectively.

8A and 8A, 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 portion, is formed on the base 80 such as Al ₂ O _3. A film is formed, and a resist pattern 82 for lift-off is formed thereon. Next, as shown in FIGS. 8B1 and 8B2, 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. 8C1 and 8C2, a conductive film 83 made of Au or the like serving as a side conductor layer is formed by sputtering 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. 8D1 and 8D2, after the resist pattern 84 is formed, the dielectric film 81 and the conductive film 83 are removed except for the portion directly below the resist pattern 84 by using an ion milling method or the like. Remove unnecessary parts. Next, as shown in FIGS. 8E1 and 8E2, 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. 8E2 is ground, so that the ff line in FIG. 8E2 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. 8F, the near-field light generating part 38, the waveguide layer 86 made of the backfill dielectric film 85, the waveguide layer 87 formed thereafter, and a plurality of 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. 9 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. 9, 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. FIG. 3 is a cross-sectional view taken along line AA of FIG. 3 schematically showing the configuration of the main part of the first embodiment of the thin film magnetic head shown in FIG. 3, and a plan view showing the shapes of the waveguide part and the near-field light generating part. It is a top view which shows the shape in the head end surface of a near-field light generation part. FIG. 4 is a perspective view showing a second embodiment of the thin film magnetic head according to the present invention, which is attached to the tip of the HGA shown in FIG. 2. It is sectional drawing and a perspective view which show the various changes about the waveguide part and near-field light generation part with which the thin film magnetic head by this invention is provided. 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 30 Air bearing surface (ABS)
300, 64, 70 Head end face 31, 65 Element formation surface 33, 62 MR effect element 330 Lower electrode layer 332 MR effect laminate 334 Upper electrode layer 34, 63, 69 Electromagnetic coil element 340, 691 Main magnetic pole layer 340a End part 340b 344a, 38a, 68a, 691a End 341 Gap layer 342 Coil layer 343 Coil insulating layer 344, 690 Auxiliary magnetic pole layer 35, 35 'Light receiving recess 350 Bottom surface 36, 36', 66 Reflecting portion 360 Reflecting layer 37, 37 ', 67 Waveguide section 370 Waveguide reflection section 371 Waveguide rectilinear section 38, 38 ', 61, 68 Near-field light generating section 39 Signal terminal electrode 40, 40' Covering layer 41 Adhesive 42 Antireflection film 43 Side conductor layer 44 Between elements Shield layer 50 Center line 610 Light receiving surface 71 Dielectric film 72 Resist pattern 73 74 Ar ion 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 (10)

A substrate having a medium facing surface and an element forming surface perpendicular to the medium facing surface, and an electromagnetic coil element for data writing formed on the element forming surface and having an end reaching the head end surface on the medium facing surface side A near-field light generating part having an end reaching the head end surface on the medium facing surface side for generating a near-field light to heat the magnetic recording medium during writing, the electromagnetic coil element, and the proximity A thin film magnetic head comprising a coating layer formed on the element forming surface so as to cover the field light generating portion,
On the upper surface of the covering layer, a light receiving recess is formed, into which an end of an optical fiber for irradiating the near-field light generating portion can be inserted, and above the element forming surface, the light receiving recess A thin film magnetic head, characterized in that a reflecting portion for reflecting light from the optical fiber and directing it toward the near-field light generating portion is provided immediately below.   A magnetoresistive effect element for reading data having an end reaching the head end surface on the medium facing surface side is further provided on the element forming surface, and the near-field light generating unit includes the magnetoresistive effect element and the magnetoresistive effect element. The reflecting portion is located between the magnetoresistive element, the near-field light generating portion, and the electromagnetic coil element when viewed from the head end surface on the medium facing surface side. The thin film magnetic head according to claim 1, wherein the thin film magnetic head is provided.   A magnetoresistive effect element for reading data having an end reaching the head end surface on the medium facing surface side is further formed on the element forming surface, and the near-field light generating unit includes the magnetoresistive effect element and the magnetoresistive effect element. 2. The electromagnetic coil element according to claim 1, wherein the reflecting portion is located obliquely behind the near-field light generating portion when viewed from the head end surface on the medium facing surface side. 2. The thin film magnetic head according to 1.   A waveguide portion including an optical path from the bottom surface of the light receiving depression to the near-field light generating portion via the reflecting portion is formed from a material having a higher refractive index than the material forming the covering layer. The thin film magnetic head according to claim 1, wherein the thin film magnetic head is a magnetic head.   The waveguide section is tapered toward the head end face in the vicinity of the head end face on the medium facing surface side, and the near-field light generating section is formed of the same material as that forming the waveguide section. The side conductor layers made of a conductive material are in contact with the tapered portion of the waveguide portion and both sides of the near-field light generating portion in the track width direction. 5. The thin film magnetic head according to claim 4, wherein the thin film magnetic head is formed in contact with each other.   The electromagnetic coil element has a main magnetic pole for generating a write magnetic field, and an end of the near-field light generating unit that reaches the head end surface on the medium facing surface side is the medium facing surface of the main magnetic pole. 6. The thin film magnetic head according to claim 5, wherein the thin film magnetic head is close to an end that reaches the side head end surface.   The thin film magnetic head according to claim 1, wherein the reflecting portion is a reflecting layer having a reflecting surface that is curved so as to restrict light from the optical fiber.   The thin film magnetic head according to claim 1, wherein a single-layer or multilayer antireflection film is formed on a bottom surface of the light receiving depression.   9. 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 comprising a magnetoresistive effect element. And a signal line for the magnetoresistive effect element, and further comprising an optical fiber having one end inserted and fixed in the light receiving recess. 10. A head gimbal assembly according to claim 9, comprising at least one magnetic recording medium, a light source for supplying light to the optical fiber, and the thin film with respect to the at least one magnetic recording medium A magnetic disk device, further comprising a recording / reproducing and light emission control circuit for controlling write and read operations performed by the magnetic head and controlling a light emission operation of the light source.

Images