JP6066656B2 - Near-field light utilization head and information recording / reproducing apparatus including the same - Google Patents

Description

  The present invention relates to a head for recording and reproducing various types of information on a recording medium using near-field light and an information recording / reproducing apparatus including the head.

  In recent years, an information recording / reproducing apparatus such as a hard disk drive in a computer device has been demanded to have a higher density in response to a need to record and reproduce a larger amount of high-density information. Therefore, in order to minimize the influence of adjacent magnetic domains and thermal fluctuation, it is considered to employ a recording medium having a strong coercive force. Therefore, it has been difficult to record information on the recording medium.

  Therefore, in order to eliminate the above-mentioned problems, a magnetically assisted magnetic recording system in which the magnetic domain is locally heated using near-field light to temporarily reduce the coercive force and during which writing to the recording medium is performed. A recording head and an information recording / reproducing apparatus have been devised and developed.

  A recording head based on the heat-assisted magnetic recording system requires a near-field light element for generating near-field light and an optical system for driving it. Various types of near-field light elements and optical systems have been devised.

  For example, as shown in Patent Document 1 and Patent Document 2, there is provided a configuration in which a light scatterer made of gold or the like that generates near-field light is provided adjacent to the main magnetic pole, and the light scatterer is irradiated with light from the laser. Are known.

JP 2005-004901 A JP 2008-159158 A

  However, in the near-field light utilization head, additional energy is required to generate near-field light with respect to the magnetic recording head that does not use near-field light, and the power consumption of the information recording / reproducing apparatus increases. . The increase in power consumption depends on the efficiency of the near-field light generating element. If the efficiency of the near-field light generating element is low, the power consumption is greatly increased. If the near-field light intensity is sufficiently secured, the near-field light element may be damaged by heat due to the loss energy. The near-field light element according to the above-described prior art cannot be said to have sufficient efficiency in this respect, and improvement has been demanded.

  Accordingly, the present invention has been made in view of such circumstances, and its purpose is to propose a near-field light utilization head having a near-field light element having high light utilization efficiency, thereby realizing low power consumption. It is an object to provide an information recording / reproducing apparatus capable of performing the above.

In order to achieve the above object, the present invention provides the following means.
A near-field light utilization head for thermally-assisted magnetic recording according to the present invention has a core that propagates a light beam from one side to the other and generates near-field light that is irradiated onto the recording medium. The near-field light utilizing head that heats the recording medium and applies a recording magnetic field to the recording medium, the core having a base surface, a first surface inclined with respect to the base surface, and a first surface inclined with respect to the first surface Two sides, an intersection where the sides of the first surface and the sides of the second surface intersect, a first end of the first surface opposite to the intersection, and a second end of the second surface opposite to the intersection. And the crossing side is provided on the base surface side from the first end and the second end, and the distance between the base surface and the crossing side is from one to the other in the direction in which the light beam propagates. The light generation part which becomes short toward and generates near-field light is provided on the other side.

  In the near-field light utilization head for heat-assisted magnetic recording according to the present invention, the light flux from the light source can be converted into near-field light with high light utilization efficiency, and thus the minute area of the recording medium is efficiently heated. be able to.

  In the near-field light utilizing head for thermally-assisted magnetic recording according to the present invention, the first metal film is formed on the first surface and the second surface, and the second metal film is formed on the base surface. It is characterized by that.

  In the near-field light utilizing head for thermally-assisted magnetic recording according to the present invention, the antenna effect can be expressed by the first metal film, the second metal film, and the core sandwiched between them, which is high. The light flux from the light source can be converted into near-field light with the light utilization efficiency, and thus a minute region of the recording medium can be efficiently heated.

  In the near-field light utilizing head for thermally assisted magnetic recording according to the present invention, the second surface opposes the first surface via a magnetic pole that applies a recording magnetic field to the recording medium, and the magnetic pole is formed of the first metal film. It is characterized by being adjacent to the intersection.

  In the near-field light utilizing head for thermally-assisted magnetic recording according to the present invention, the magnetic pole and the light generation unit are close to each other, so that the magnetic flux from the magnetic pole and the near-field light from the light generation unit are close to each other. Occur. Therefore, the magnetic flux and the near-field light can efficiently cooperate, and as a result, fine magnetic information can be efficiently recorded on the recording medium.

  The near-field light utilizing head for thermally assisted magnetic recording according to the present invention is characterized in that a protective film is formed between the magnetic pole and the first metal film.

  In the near-field light utilizing head for thermally-assisted magnetic recording according to the present invention, the magnetic pole and the first metal film are electrically connected to each other because of the protective film (separating film) that separates the magnetic pole and the first metal film. It is insulated, and the influence on the surface plasmon which is a wave of free electrons on the first metal film can be reduced, and near-field light can be generated efficiently. It is also possible to avoid damage caused by alloying the magnetic pole and the first metal film.

  The near-field light using head for thermally assisted magnetic recording according to the present invention is characterized in that it constitutes a spot size converter that narrows the spot size of the light beam as the core faces the light generating portion.

  In the near-field light using head for thermally-assisted magnetic recording according to the present invention, even if a light source having a large spot size is used, most of the light energy can be converted into near-field light by narrowing the spot size. As a result, the minute area of the recording medium can be efficiently heated.

  The near-field light using head for thermally assisted magnetic recording according to the present invention is characterized by constituting a spot shape converter that deforms the spot shape of a light beam as the core faces the light generating portion. .

  In the near-field light utilization head for thermally-assisted magnetic recording according to the present invention, even if a semiconductor laser that generates an elliptical spot-shaped outgoing beam is used as the light source, the light utilization efficiency is hardly reduced.

  A near-field light utilizing head for thermally assisted magnetic recording according to the present invention includes a coil that generates a magnetic field in a magnetic pole and a slider that holds a core. The information recording / reproducing apparatus according to the present invention includes a head gimbal assembly that supports a near-field light utilizing head directly above a recording medium.

  Since the information recording / reproducing apparatus according to the present invention includes the near-field light utilization head for the heat-assisted magnetic recording of the present invention, it is possible to reduce power consumption during information recording.

  According to the near-field light utilization head for thermally-assisted magnetic recording according to the present invention, it is possible to convert a light beam from a light source into near-field light with high light utilization efficiency, and thus efficiently heat a minute region of a recording medium. Accordingly, an information recording / reproducing apparatus with low power consumption during information recording can be provided.

It is a block diagram which shows the information recording / reproducing apparatus which concerns on 1st Embodiment of this invention. It is a perspective view of the head gimbal assembly of the information recording / reproducing apparatus shown in FIG. FIG. 3 is a cross-sectional view taken along line A-A ′ of FIG. 2. It is the perspective view which showed the structure of the core 311 among FIG. FIG. 4 is an enlarged view of a part of the vicinity of the recording medium D of the light guide and the main magnetic pole 310 in FIG. FIG. 6 is a bottom view of FIG. 5 as viewed from ABS, which is the side of the slider 2 facing the recording medium D. FIG. It is a figure which shows the manufacturing method of the core 311 and the micro gap 315. FIG. The figure on the left side is a plan view of the core 311, and the figure on the right side is a cross-sectional view of a cross section in the right direction from the one-dot chain line BB ′ on the left side. It is a figure which shows the variation of 1st Embodiment of this invention, and is the bottom view seen from the same direction as FIG. It is a figure which shows another variation of 1st Embodiment of this invention, and is the bottom view seen from the same direction as FIG. It is a figure which shows another variation of 1st Embodiment of this invention, and is the bottom view seen from the same direction as FIG. It is a figure which shows another another variation of 1st 1st Embodiment of this invention, and is the bottom view seen from the same direction as FIG. It is a figure which shows 2nd Embodiment of this invention, and is sectional drawing seen from the same direction as FIG. It is a perspective view which shows 3rd Embodiment of this invention.

(First embodiment)
The basic configuration of the first embodiment according to the present invention will be described below with reference to FIGS. FIG. 1 is a configuration diagram showing an information recording / reproducing apparatus 1 according to the present embodiment. In addition, the information recording / reproducing apparatus 1 of this embodiment is an apparatus which writes with respect to the recording medium D which has a magnetic-recording layer with a heat-assisted magnetic recording system.

  As shown in FIG. 1, in the information recording / reproducing apparatus 1 of this embodiment, a suspension 3 to which a slider 2 is fixed is fixed to a carriage 11. The slider 2 and the suspension 3 are collectively referred to as a head gimbal assembly 12. The disc-shaped recording medium D is rotated in a predetermined direction by the spindle motor 7. The carriage 11 is rotatable about the pivot 10 and is rotated by an actuator 6 controlled by a control signal from the control unit 5, so that the slider 2 can be disposed at a predetermined position on the surface of the recording medium D. The housing 9 has a box shape made of aluminum or the like (in FIG. 1, the peripheral wall surrounding the periphery of the housing 9 is omitted for easy understanding), and the above components are stored therein. The spindle motor 7 is fixed to the bottom surface of the housing 9. The slider 2 includes a recording element (not shown) for generating a magnetic field toward the recording medium D, a light guide unit (not shown) for generating near-field light, and a reproducing element (for reproducing information recorded on the recording medium D). (Not shown). The recording element and the reproducing element are connected to the control unit 5 through the flexible wiring 13 laid along the suspension 3 and the carriage 11, the terminal 14 provided on the side surface of the carriage 11, and the flat cable 4.

  One recording medium D may be provided, but a plurality of recording media may be provided as shown in FIG. As the number of recording media D increases, the number of head gimbal assemblies 12 also increases. Although FIG. 1 shows a configuration in which the head gimbal assembly 12 is arranged only on one side of the recording medium D, it may be arranged on both sides. Therefore, the number of head gimbal assemblies 12 is at most twice the number of recording media D. Thereby, the recording capacity per information recording / reproducing apparatus can be increased.

  FIG. 2 is an enlarged view of the head gimbal assembly 12 according to the present embodiment. The suspension 3 includes a base plate 201 made of a thin stainless plate, a hinge 202, a load beam 203, and a flexure 204. The base plate 201 is fixed to the carriage 11 by mounting holes 201a provided in a part thereof. The hinge 202 connects the base plate 201 and the load beam 203. The hinge 202 is thinner than the base plate 201 and the load beam 203, and the suspension 3 is bent around the hinge 202. The flexure 204 is an elongate member fixed to the load beam 203 and the hinge 202, is thinner than the load beam 203 and the base plate 201, and is easily bent. A substantially rectangular parallelepiped slider 2 is fixed to the tip of the flexure 204.

  The surface opposite to the surface fixed to the flexure 204 in the surface of the slider 2 is a surface facing the recording medium D. This surface is a surface that generates a pressure for the slider 2 to rise from the viscosity of the air flow generated by the rotating recording medium D, and is called ABS (Air Bearing Surface). An uneven shape (not shown) is provided on the ABS, and a desired pressure distribution is generated between the slider 2 and the recording medium D. The slider 2 floats in a desired state due to the balance between the positive pressure for separating the slider 2 from the recording medium D, the negative pressure for attracting the slider 2 to the recording medium D, and the pressing force of the suspension 3. The minimum clearance between the recording medium D and the slider 2 is 10 nm or less. The pressing force by the suspension 3 is mainly generated by the elasticity of the hinge 202. Further, since the hinge 202 and the flexure 204 are bent with respect to the undulation of the surface of the recording medium D, a desired floating state can be maintained.

  Flexible wiring 13 is provided on the flexure 204. The flexure 204 has a substantially U-shaped opening, and the slider 2 is fixed on a pad portion 204a that is surrounded by the opening and has a tongue shape. Of the ends of the slider 2, the base side (carriage 11 side) of the suspension 3 is called an inflow end. The tip side of the opposite suspension 3 is called the outflow end of the slider 2. These are named based on the direction of the air flow by the recording medium D described above. The flexible wiring 13 extended from the base side of the suspension 3 branches into two from the middle, and is connected to the outflow end side of the slider 2 so as to go around the opening and both sides of the slider 2.

  FIG. 3 is a cross-sectional view taken along the line A-A ′ of FIG. 2. The slider 2 includes a slider base 301, a recording element, a light guide unit, a reproducing element 304, and a laser unit 501. On the side surface on the outflow end side of the slider base 301, a reproducing element 304, a recording element, and a light guide are stacked. A laser unit 501 is provided between the slider base 301 and the pad portion 204a. The laser unit 501 includes a laser substrate 502 and a laser 503, and the laser 503 is fixed to the laser substrate 502. The laser substrate 502 is fixed to the slider base 301 and the pad portion 204a. The laser 503 is an edge-emitting laser, the end surface from which the laser beam is emitted is substantially parallel to the ABS, and the laser 503 and the light guide are optically connected. The laser 503 is connected to the control unit 5 through the laser substrate 502 and the flexible wiring 13. The laser 503 emits light based on the electrical signal from the control unit 5. The slider base 301 is a substantially rectangular parallelepiped member and is made of an AlTiC material or the like.

  The recording element includes a sub magnetic pole 306 fixed to the side surface on the outflow end side of the reproducing element 304, and a main magnetic pole 310 connected to the sub magnetic pole 306 via a yoke 307 and applying a recording magnetic field perpendicular to the recording medium D. And a coil 308 that spirally winds around the yoke 307 around the yoke 307. The main magnetic pole 310, the sub magnetic pole 306, and the yoke 307 are made of a high saturation magnetic flux density (Bs) material (for example, CoNiFe alloy, CoFe alloy, etc.) having a high magnetic flux density. Further, the coil 308 is arranged so that a gap is left between adjacent coil wires, the yoke 307, the main magnetic pole 310, and the sub magnetic pole 306 so as not to be short-circuited, and in this state, the clad 312 having insulation properties. (Described later). The coil 308 is connected to the control unit 5 via the flexible wiring 13, and a current modulated according to information is supplied from the control unit 5. Therefore, the main magnetic pole 310, the sub magnetic pole 306, the yoke 307, and the coil 308 constitute an electromagnet as a whole. The main magnetic pole 310 and the sub magnetic pole 306 are designed so that the end surfaces facing the recording medium D are flush with the ABS of the slider 2.

  The light guide section is composed of a polyhedral core 311, a clad 312 that confines the core 311 inside, a first metal film 313 and a second metal film 314 described later, and is formed in a substantially plate shape as a whole. ing. The core 311 is disposed so as to be sandwiched between the main magnetic pole 310 and the sub magnetic pole 306 and through the yoke 307 with one end side facing the flexure 204 side and the other end side facing the recording medium D side. Yes. The yoke 307 may be configured to penetrate the core 311. The core 311 is made of a material that is optically transparent and has a higher refractive index than the clad 312. For example, the core 311 can be made of germanium-doped SiO2, and the clad 312 can be made of pure SiO2. Further, Ta 2 O 5 can be used for the core 311 and alumina can be used for the clad 312. If the laser light from the laser 503 is infrared light, silicon can be used for the core 311. A part of one end side of the core 311 is exposed from the clad 312 and is opposed to the emission end face of the laser 503, thereby realizing an optical connection between the light guide unit and the laser 503.

  The reproducing element 304 is a magnetoresistive film whose electric resistance changes according to the magnitude of the magnetic field leaking from the recording medium D. A bias current is supplied to the reproducing element 304 from the control unit 5 via a lead film (not shown) and the flexible substrate 13. Thereby, the control unit 5 can detect a change in the magnetic field leaking from the recording medium D as a change in voltage, and can reproduce a signal from the change in voltage.

The detailed shape of the core 311 will be described with reference to FIG. One end side of the core 311 has a trapezoidal shape in a cross section orthogonal to the longitudinal direction from the one end side toward the other end side (the tip end side of the core 311). Further, the vicinity of the middle between the one end side and the other end side has a triangular cross section, and thus the core 311 has a ridge line 311a having a triangular cross section. In the vicinity of the other end side, the ridge line 311a is a ridge line 311b divided into two branches, and an inclined V-groove 311c where the side surfaces of two inclined cores 311 intersect is formed between the ridge lines 311b. In the future, the portion of the core 311 from which the ridge line is divided into two is referred to as the core tip 311d. One end side of the core 311 is the side where the flexure 204 exists, and the other end side is the side where the ABS exists. The one end side may be called one of the cores 311 and the other end side may be called the other of the cores 311. The light beam converted into near-field light propagates from one side of the core 311 toward the other side. Further, the bottom of the inclined V-groove 311c where the side surfaces of the two inclined cores 311 intersect is called an intersecting side 311e. The inclined V groove 311c has a first surface 311f and a second surface 311g that are inclined with respect to the intersection 311e. The opposite surface on which the ridge line 311a and the bifurcated ridge line 311b of the core 311 are provided is referred to as a base surface 311h. The first surface 311f formed to be inclined to the base surface 311h is also formed to be inclined to the second surface 311g. The ridgeline 311a and the bifurcated ridgeline 311b are formed so as to approach the base surface 311h as approaching the other end side. One of the bifurcated ridgeline 311b is a first end, and the other bifurcated ridgeline 311b is a second end. The first end constitutes one side of the first surface 311f. The second end constitutes one side of the second surface 311g. The first end and the second end constitute a substantially V shape in plan view. The ridgeline 311a is aligned with the first end portion and the second end portion, and is substantially Y-shaped in plan view. The first surface 311 f has a triangular shape surrounded by the intersection 311 e, the first end, and the tip of the core 311. The second surface 311 g has a triangular shape surrounded by the intersection 311 e, the second end, and the tip of the core 311. The first end and the second end intersect with the intersection 311e, and also intersect with the ridge line 311a at the intersection. In this positional relationship, the first end is provided on the opposite side of the intersection 311e on the first surface 311f while sharing the intersection with the intersection 311e. The second end portion is provided on the opposite side of the intersection 311e on the second surface 311g while sharing the intersection with the intersection 311e.
The intersecting side 311e is formed with a gradient so as to approach the base surface 311h from one side where the ridge line 311a exists toward the other side which is the other end of the core tip 311d. That is, the inclined V-groove 311c is formed so that the V-groove is gradually deepened toward the other end of the core tip 311d. On the other end of the core tip 311d, that is, on the surface (ABS) facing the recording medium that is the tip of the core 311 is formed a minute gap 315 that is a light generating portion. As the minute gap 315 approaches the other end of the core tip 311d, the intersection 311e and the base surface 311h gradually approach each other, and the position where the intersection 311e and the base surface 311h are closest to each other, that is, the intersection 311e, It is formed at a position where the base surface 311h and the other end of the core tip 311d substantially intersect. The angle formed by the first surface 311f and the second surface 311g with the intersecting side 311e therebetween is preferably 20 degrees to 60 degrees. Further, the smaller the radius of curvature of the intersection 311e is, the better, 100 nm to several nm. As a result, the luminous flux from the light source can be converted into near-field light with high light utilization efficiency, and the minute area of the recording medium can be efficiently heated.
The core 311 is drawn so that the cross-sectional area gradually decreases toward the other end side from one end side to the core front end 311d. For example, the ridgeline 311a is formed so as to approach the base surface 311h as it approaches the other end side. The core 311 and the clad 312 also serve as a spot shape converter for converting the spot shape of the introduced light beam and a spot size converter for reducing the spot size, in addition to the fact that the cross-sectional shape changes from a trapezoid to a triangle. Is configured. That is, from the one end side of the core 311 to the front side of the core tip 311d, the spot size converter is drawn so that the cross-sectional area gradually decreases toward the other end side, and the cross-sectional shape of the core 311 is changed from a trapezoid to a triangle. It has a spot shape converter that changes to In general, when a semiconductor laser that generates an elliptical spot-shaped outgoing beam is used as the laser 503, it is advantageous in terms of light utilization efficiency to have a spot shape converter.

  A detailed structure near the core tip 311d and the main magnetic pole 310 will be described with reference to FIGS. FIG. 5 is an enlarged cross-sectional view of the slider 2 in the vicinity of the core tip 311d. FIG. 6 is a bottom view of FIG. 5 as viewed from the ABS side of the slider 2. The inclined V groove 311c is covered with the first metal film 313. That is, the first surface 311f and the second surface 311g are covered with the first metal film 313. Further, the side surface of the core tip 311 d that faces the inclined V groove 311 c is covered with the second metal film 314. That is, the base surface 311h is covered with the second metal film 314. The direction of the light beam propagating through the core 311 and the second metal film 314 are disposed substantially in parallel, and the first metal film 313 forms a predetermined angle with the direction of the light beam. Therefore, the first metal film 313 is provided obliquely with respect to the second metal film 314, that is, the first metal film 313 and the second metal film 314 move toward the recording medium side of the core 311. It is equipped so that the space | interval of may become narrow. In the first metal film 313 and the second metal film 314, in the intersecting side 311e of the inclined V-groove 311c, the closest point of both forms a minute gap 315, and the gap interval is about 100 nm to several nm. It is. Further, the minute gap 315 is exposed to the recording medium D so as to be flush with the ABS. The first metal film 313 and the second metal film 314 are made of a material such as gold, silver, or platinum. Light emitted from the laser 503 is propagated inside the core 311, converted into surface plasmons between the first metal film 313 and the second metal film 314, propagated to the minute gap 315 in the surface plasmon state, and recorded. The surface plasmon is converted into near-field light by the minute gap 315 exposed toward the medium D, so that the minute part of the recording medium D is irradiated. The first metal film 313, the second metal film 314, and the core 311 sandwiched between them form a so-called MIM (Metal-Insulator-Metal) structure and have an antenna effect against electromagnetic waves. Therefore, it is possible to collect light emitted from the laser 503 and generate strong near-field light in the minute gap 315. The main magnetic pole 310 has a main magnetic pole tip 310a in the vicinity of the recording medium D. The end surface of the main magnetic pole tip 310a facing the recording medium D is flush with the ABS of the slider 2. As a result, the main magnetic pole tip 310a is arranged along the first metal film 313 so as to be embedded in the inclined V-groove 311c. That is, the main magnetic pole tip 310a is sandwiched between the first surface 311f and the second surface 311g of the core 311 and embedded up to a position facing the intersecting side 311e, and has a triangular pyramid shape facing the inclined V groove 311c. Yes. However, the main magnetic pole tip 310a and the first metal film 313 are separated by a separation film 316 as a protective film so as not to be in direct contact. Since the main magnetic pole tip 310a and the minute gap 315 are close to each other with only a separation film 316 having a film thickness of about several nanometers therebetween, the magnetic flux from the main magnetic pole tip 310a and the near-field light from the minute gap 315 are in close proximity. It occurs in the form. Because of the separation film 316, the main magnetic pole tip 310a and the first metal film 313 are electrically insulated, reducing the influence on the surface plasmon that is a wave of free electrons on the first metal film 313, It is possible to generate near-field light efficiently. Further, it is possible to avoid damage caused by alloying the main magnetic pole tip 310a and the first metal film 313.

A method for manufacturing the core 311 and the minute gap 315 will be described with reference to FIGS. The left column of FIG. 7 is a plan view, and the right column is a BB ′ cross section. The plan view in the left column is a view from the side where the surface opposite to the base surface 311h of the core 311 can be seen.
First, as shown in FIG. 7A, an upper clad 312a, a metal film base material film 901, and a core base material film 902 constituting a part of the clad 313 are formed on the slider base 301. The reproducing element 306 and the coil 308 are also appropriately formed on the slider base 301, but description thereof is omitted here. Although the processing of one element is shown here, a plurality of elements can be processed at once by using a substrate to which a plurality of slider bases 301 are connected. A resist pattern 903 having a Y-shape in plan view is formed on the core base material film 902. The resist pattern 903 is formed by applying a photoresist to the entire surface of the core base material film 902, and exposing and developing with a Y-shaped mask pattern.
Next, as shown in FIG. 7B, the resist pattern 903 is transferred to the core base material film 902 by etching. If the material of the core base material film 902 is SiO2, it can be etched by RIE (reactive ion etching) using a CF-based gas. Thereafter, the remaining resist pattern 903 is removed using an organic solvent or acid. As a result, a pattern 902a having a Y-shape and a rectangular section in plan view is formed on the surface of the core base material film 902.
Next, as shown in FIG. 7C, a pattern 902a having a rectangular cross section is processed into a core 311 having a triangular cross section and a trapezoidal cross section. For this, sputter etching using Ar gas is used. As a result, the corners of the rectangular cross section of the pattern 902a are selectively etched and processed into a triangular cross section or a trapezoidal cross section having inclined side surfaces. A bifurcated ridge line 311b having a first end and a second end is formed at the apex of the triangular cross section. Of the inclined side surfaces, the first surface 311f and the second surface 311g are processed so as to be inclined and face each other. As a result, the base of the Y-shaped bifurcated portion of the core 311 becomes an inclined V-groove 311c composed of this inclined side surface. The inclined V-groove 311c is surrounded by the first surface 311f and the second surface 311g, and an intersection 311e where the first surface 311f and the second surface 311g intersect is the bottom of the inclined V-groove 311c. The intersecting side 311e is directed from one side of the core 311 to the other side, that is, the direction in which the Y-shape of the bifurcated ridgeline 311b having the first end and the second end extends from the bifurcated portion (the direction toward the left in the left column view). ) Toward the base surface 311h. At this time, the metal film base material film 901 is also etched to form the second metal film 314 on the base surface 311h.
Next, as shown in FIG. 7D, the first metal film 313, the main magnetic pole tip 310a, and a part of the cladding 313 are formed on the first surface 311f and the second surface 311g on the inclined V groove 311c. The clad 312b is formed, and the surface is flattened by polishing. A film forming method such as a CVD (chemical vapor deposition) method can be used to form the upper clad 312b. Thereafter, cutting is performed so as to cross the long axis of the core 311 and the cut surface is polished to form a minute gap 315 which is a light generating portion.
The above manufacturing method can form a fine and three-dimensional structure by applying a general semiconductor manufacturing technique. Since the minute gap 315 is provided at a position where the first surface 311f and the base surface 311h, the second surface 311g and the base surface 311h, and the intersecting side 311e and the base surface 311h are concentrated at one point, the light concentrated from multiple directions is diffused. It is possible to irradiate the recording medium D soon after that, and it is possible to easily manufacture a near-field light utilization head having high light utilization efficiency.

  FIG. 8 is a diagram showing a variation of this embodiment, and corresponds to FIG. Of the side surface of the core tip 311d, the side surface that is not covered by the first metal film 313 and the second metal film 314 is covered by the light shielding film 317. In the present embodiment, the first surface 311f, the second surface 311g, and the base surface 311h are not formed, and the light shielding film 317 is formed on the surface on which the inclined V groove 311c is not formed. The light shielding film 317 may cover at least part of the first metal film 313, the second metal film 314, and the main magnetic pole tip 310a. For the light-shielding film 317, a metal material having high reflectivity, for example, aluminum is preferably used. Since the light can be confined inside the core tip 311d by the metal reflection on the surface of the light shielding film 317, the light is more easily concentrated in the minute gap 315, and the light utilization efficiency can be further improved.

  FIG. 9 is a diagram showing another variation of the present embodiment, and corresponds to FIG. Compared to FIG. 6, the separation film 316 is eliminated. The first metal film 313 is in direct contact with the first surface 311 f and the second surface 311 g, and the main magnetic pole tip 310 a and the first metal film 313 are in contact with each other. Direct contact. Since the structure is simpler than that of FIG. 6, the manufacture is facilitated. Further, since the main magnetic pole tip 310a and the minute gap 315 can be brought closer to each other, the magnetic flux and the near-field light can collaborate more efficiently, thereby further improving the recording efficiency of the fine magnetic information on the recording medium. be able to.

  FIG. 10 is a diagram showing still another variation of the present embodiment, and corresponds to FIG. In FIG. 6, the core 311 has a W-shaped cross section, but may have an M-shaped cross section in this way. With this structure, the width of the second metal film 314 formed on the base surface 311h can be adjusted. Since the antenna effect of the MIM structure is derived from the resonance phenomenon, the effect depends on the size of each part. Compared with FIG. 6, by adjusting the width of the second metal film 314, the antenna effect of the MIM structure including the first metal film 313, the second metal film 314, and the core 311 sandwiched therebetween is enhanced. Can do. Therefore, it is possible to collect light emitted from the laser 503 and generate stronger near-field light in the minute gap 315.

  FIG. 11 is a diagram showing still another variation of the present embodiment, and corresponds to FIG. In FIG. 6, the main magnetic pole tip 310a has a triangular cross section that fills the triangle formed by the first surface 311f and the second surface 311g, but it may be a pentagonal cross section as shown in FIG. The first metal film 313 and the separation film 316 do not necessarily need to cover the entire first surface 311f and the second surface 311g, and have the same width as the main pole tip 310a having a pentagonal cross section, and the first surface 311f and the second surface 311g. May be covered. By making the tip of the main pole a pentagon, the width (vertical direction in the figure) can be made narrower than in the above embodiment. Therefore, the magnetic flux emitted from the tip of the main magnetic pole has a narrower cross section and a higher density. Therefore, the cooperation with near-field light at the time of information recording becomes more efficient, and the accuracy of data recording in a fine area can be further improved.

  According to the present embodiment, the light beam propagated from the laser 503 through the core 311 once has the first surface 311f, the second surface 311g, the base surface 311h, and the intersection between the first metal film 313 and the second metal film 314. Through the surface plasmon at 311e, near-field light is first generated on the surface of the slider 2 from the minute gap 315, and the minute region of the recording medium D is heated. With this configuration, it is possible to convert the light beam from the laser 503 into near-field light with high light utilization efficiency, and thus it is possible to efficiently heat a minute region of the recording medium D. As a result, the power consumption of the information recording / reproducing apparatus 1 can be reduced.

(Second Embodiment)
FIG. 12 is a diagram showing a second embodiment according to the present invention, and corresponds to FIG. 3 in the first embodiment. In this case, the slider base 301, the recording element 302, the light guide element, and the reproducing element 304 are simply stacked. The main magnetic pole 310 is disposed on the second metal film 314 side. In this embodiment, the same effects as those of the first embodiment are obtained, and since the structure is simpler than that of the first embodiment, the manufacture is facilitated.

(Third embodiment)
FIG. 13 is a diagram showing a third embodiment according to the present invention, and corresponds to FIG. 4 in the first embodiment. In this case, a portion of the core 311 other than the core tip 311d is a simple triangular prism whose cross section does not change, and does not have a function of a spot shape converter or a spot size converter that requires a cross section change. Together with the optical waveguide. If the spot shape of the light beam from the laser 503 is a perfect circle and the spot size is sufficiently small, the light utilization efficiency does not decrease even with such a configuration. Further, any polyhedral shape such as a quadrangular prism may be used instead of the triangular prism. In this embodiment, the same effects as those of the first embodiment are obtained, and since the structure is simpler than that of the first embodiment, the manufacture is facilitated.

  It should be noted that the technical scope of the present invention is not limited to the above-described embodiments, and includes those in which various modifications are made to the above-described embodiments without departing from the spirit of the present invention. In other words, the configuration described in the above-described embodiment is merely an example, and can be changed as appropriate. Moreover, it is also possible to employ | adopt combining each embodiment mentioned above suitably.

D Recording medium 1 Information recording / reproducing apparatus 2 Slider 3 Suspension 11 Carriage 12 Head gimbal assembly 13 Flexible wiring 204 Flexure 204a Pad portion 306 Sub magnetic pole 308 Coil 310 Main magnetic pole 311 Core 311a Ridge line 311c Inclined V groove 311e Crossing side 311f First surface 311g Second surface 311h Base surface 312 Cladding 313 First metal film 314 Second metal film 315 Micro gap 316 Separating film (protective film)
317 light shielding film

Claims (8)

A near field that propagates a light beam from one side to the other and generates a near-field light that irradiates the recording medium, heats the recording medium with the near-field light, and applies a recording magnetic field to the recording medium In the light utilization head,
The core is
A base surface, a first surface inclined with respect to the base surface, a second surface inclined with respect to the first surface,
An intersection where the side of the first surface and the side of the second surface intersect;
A first end of the first surface opposite to the intersecting side;
A second end of the second surface opposite to the intersecting side;
The intersecting side is provided on the base surface side from the first end and the second end,
The distance between the base surface and the intersecting side becomes shorter from the one side toward the other side,
A light generator for generating the near-field light is provided on the other side ;
A near-field light utilizing head , wherein a metal film is formed on the first surface and the second surface, and forms a predetermined angle with the direction of the light beam.   The near-field light utilizing head according to claim 1, wherein a first metal film is formed on the first surface and the second surface, and a second metal film is formed on the base surface.   3. The second surface is opposed to the first surface via a magnetic pole that applies the recording magnetic field to the recording medium, and the magnetic pole is adjacent to the intersecting side via the first metal film. Near-field light utilization head.   The near-field light utilizing head according to claim 3, wherein a protective film is formed between the magnetic pole and the first metal film.   The near-field light utilizing head according to claim 3, comprising a coil that generates a magnetic field in the magnetic pole, and a slider that holds the core.   The near-field light utilization head according to claim 1, wherein the core constitutes a spot size converter that narrows a spot size of the light beam toward the light generation unit.   The near-field light utilization head according to claim 1, wherein the core constitutes a spot shape converter that deforms a spot shape of the light beam toward the light generation unit.   An information recording / reproducing apparatus having a head gimbal assembly for supporting the near-field light utilizing head according to claim 1 directly above the recording medium.

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