JP5550049B2 - Recording head and information recording / reproducing apparatus - Google Patents

Description

  The present invention relates to a recording head that records various information on a magnetic recording medium using near-field light, and an information recording / reproducing apparatus including the recording head.

  2. Description of the Related Art In recent years, magnetic recording media such as hard disks (hereinafter referred to as disks) in computer equipment have been demanded to have higher density in response to the need to record and reproduce larger amounts of high-density information. For this reason, in order to minimize the influence of adjacent magnetic domains and thermal fluctuation, a disk having a strong coercive force has begun to be adopted. Therefore, it has been difficult to record information on the disc.

Therefore, in order to eliminate the above-described problems, the coercive force is temporarily reduced by locally heating the magnetic domain using spot light that has collected light, or near-field light that has collected light, In the meantime, an information recording / reproducing apparatus of a hybrid magnetic recording system for performing writing on a disk is provided.
In particular, when near-field light is used, it is possible to handle optical information in a region that is less than or equal to the wavelength of light, which is a limit in conventional optical systems. Therefore, it is possible to achieve a higher recording bit density than conventional optical information recording / reproducing apparatuses.

Various types of recording heads based on the hybrid magnetic recording system are provided. One of them is a head that performs heating using near-field light (see Patent Document 1).
The recording head described in Patent Document 1 mainly includes an auxiliary magnetic pole, a main magnetic pole, a near-field light generating element (scatterer) that generates near-field light from the irradiated laser light, and the irradiated laser light. A lens for focusing on the near-field light generating element and a laser light source for irradiating laser light are provided, and they are arranged in this order from the outflow end face side of the slider.

  Of these, the near-field light generating element is mounted on the main magnetic pole so as to be aligned with the main magnetic pole along the head traveling direction (slider thickness direction) when viewed from the slider. Yes. Thereby, near-field light is generated near the recording magnetic field generated between the main magnetic pole and the auxiliary magnetic pole.

  However, since the main magnetic pole and the near-field light generating element are arranged side by side along the traveling direction of the head, as shown in FIG. 17, the magnetic field spot SP1 and the near-field light spot SP2 are the traveling direction of the head. It is difficult to make the spot centers G1 and G2 of the spots SP1 and SP2 coincide with each other.

  As shown in FIG. 18, the magnetic field spot SP1 is a range in which the magnetic field curve C1 of the recording magnetic field appears, and the peak position of the magnetic field curve C1 (position where the magnetic field is strongest) is the spot center G1. The magnetic field spot SP1 appears closer to the leading edge of the slider than the near-field light spot SP2 because the main magnetic pole is disposed closer to the outflow end of the slider than the near-field light generating element.

  On the other hand, the near-field light spot SP2 is a range in which a coercive force curve C2 in which the coercive force of the disk is lowered by heating with the generated near-field light appears, and the peak position of the coercive force curve C2 (maintained by heat from the near-field light) The position where the magnetic force is the lowest) is the spot center G2. The near-field light spot SP2 appears closer to the trailing edge of the slider than the magnetic field spot SP1 because the near-field light generating element is disposed closer to the outflow end of the slider than the main magnetic pole.

Ideally, it is preferable that the magnetic field spot SP1 and the near-field light spot SP2 overlap each other and the spot centers G1 and G2 of the spots SP1 and SP2 coincide with each other. By doing so, the strongest magnetic field can be applied at the position where the coercive force is the lowest, so that reliable and local writing is possible, which leads to high density recording.
However, in practice, there is no element that generates a magnetic field and near-field light at the same time, so that the main magnetic pole and the near-field light generating element are arranged side by side, and the spot center G1 of both spots SP1 and SP2 , G2 is difficult to match.

Therefore, as described above, the magnetic field spot SP1 and the near-field light spot SP2 are shifted in the traveling direction of the head, but in this case, the position where the coercive force of the disk is the lowest and the position where the magnetic field is the strongest. There is a risk that writing error or the like may occur due to deviation in the traveling direction of the head.
For this reason, in order to perform reliable writing in this case, it is necessary to increase the intensity of each of the magnetic field spot SP1 and the near-field light spot SP2 to widen the spot size. Heating another recording track, data bit, etc. located in the area, it is easy to cause problems such as erroneously erasing already recorded data or increasing power consumption.

Also, when viewed from the slider, the main magnetic pole is mounted on the near-field light generating element, and the main magnetic pole and the near-field light generating element are also aligned along the traveling direction of the head. There is also known a head arranged in (see Patent Document 2).
However, even in this case, as shown in FIGS. 19 and 20, contrary to the above case, the coercive force curve C2 appears near the leading edge and the magnetic field curve C1 appears only near the trailing edge. The magnetic field spot SP1 and the near-field light spot SP2 still deviated in the head traveling direction (arrow direction). Therefore, the same problem as described above remains.

Therefore, in the configuration described in Patent Document 1, the coercive force curve C2 shown in FIG. 18 is shifted as much as possible to the magnetic field curve C1 side so that the spot centers G1 and G2 of both spots SP1 and SP2 are along the traveling direction of the head. A head that has been devised to approach is known (see Patent Document 3).
In the main magnetic pole of the head described in Patent Document 3, a recess is formed on the trailing edge side of the facing surface facing the magnetic recording medium. And the near-field light generating element is arrange | positioned in this hollow part. With this configuration, the magnetic field spot SP1 and the near-field light spot SP2 are overlapped as much as possible in the traveling direction of the head.

Japanese Patent No. 4100133 JP 2007-207349 A JP-A-2005-4901

  However, since a recess is formed on the surface facing the main pole, the shape of the main pole changes due to the edge for forming the recess, and two sharpened portions are formed on the surface facing the main pole. Appears on the trailing edge side. For this reason, the recording magnetic field is likely to be generated locally at the two sharpened portions, and as a result, the magnetic field is likely to spread in the track direction of the magnetic recording medium. For this reason, a magnetic field is applied to another recording track or a data bit positioned next to the recording track to be written, and it is easy to erroneously erase data.

Also, when manufacturing a normal head, a recording element and a near-field light generating element are sequentially stacked on the outflow end face of the slider along the thickness direction of the slider using a photolithography technique. The method to do is generally made. Therefore, patterning in various shapes is easy as long as it is in a plane parallel to the outflow end surface of the slider.
However, since the opposing surface of the slider is a surface orthogonal to the outflow end surface of the slider, it is technically difficult to form additional recesses in this surface, such as cutting. It was a thing. Therefore, manufacturing is difficult and time-consuming.

  The present invention has been made in view of such circumstances, and the object thereof is to improve the writing reliability and achieve high-density recording, and to easily manufacture without taking time and effort. And a recording / reproducing apparatus including the recording head.

The present invention provides the following means in order to solve the above problems.
(1) A recording head according to the present invention includes a slider disposed opposite to a surface of a magnetic recording medium rotating in a fixed direction with an outflow end face facing downstream in the rotation direction of the magnetic recording medium, A light propagation element that is disposed on the outflow end face side and has a propagation part that propagates the light beam incident from one end side toward the other end side facing the surface of the magnetic recording medium; A recording element that is disposed on the outflow end face side and has a main magnetic pole and an auxiliary magnetic pole and generates a recording magnetic field between the magnetic poles, and includes at least another of the main magnetic pole and the propagation portion The end side portion is disposed in the same plane parallel to the outflow end surface of the slider, and the surface plasmon from the propagated light flux is formed on the side surface on the main magnetic pole side in the other end side portion of the propagation portion. Near-field due to excitation of Metal film to generate a is formed, the recording element has an insulating layer supporting the main magnetic pole, the insulating layer, the other end portion so enter the other end portion of the propagation portion In the same plane as the main magnetic pole, and the metal film is formed in the stepped portion located between the main magnetic pole and the other end portion of the propagation portion. It is characterized by.

According to the recording head of the present invention, the incident light beam can be reliably propagated to the other end side by using the propagation portion of the light propagation element, and the metal film can be used for this. Near-field light can be generated by exciting surface plasmons from the propagated light flux. Therefore, various information can be written on the magnetic recording medium by cooperating the near-field light generated in the metal film and the recording magnetic field generated in the recording element.
In particular, the main magnetic pole and at least the other end portion of the propagation part where the metal film is formed are arranged in the same plane parallel to the outflow end surface of the slider, so that the direction perpendicular to the traveling direction of the head That is, the main magnetic pole and the other end side portion of the propagation part can be arranged along the track direction of the magnetic recording medium. Accordingly, the main magnetic pole and the metal film can also be arranged so as to be aligned along the track direction.

Therefore, the magnetic field spot of the recording magnetic field and the near-field light spot of the near-field light can be aligned in the track direction, and the spot center of the magnetic field spot and the spot center of the near-field light coincide with the traveling direction of the head. It is possible to make it.
Usually, in the magnetic recording medium, the distance between the centers of magnetic domains adjacent in the track direction is larger than the distance between the centers of magnetic domains adjacent in the running direction of the head. Therefore, by making the spot center of both spots coincide with the traveling direction of the head, the peak of heating is applied to the magnetic domain of the target recording track without affecting the magnetic domain of another recording track adjacent in the track direction as much as possible. Heating and application of a magnetic field can be performed in a state where the peak of the magnetic field and the peak of the magnetic field are matched.

  Therefore, the writing reliability can be improved and high density recording can be achieved. In addition, since the metal film is formed on the side surface on the main magnetic pole side in the other end portion of the propagation portion, the magnetic field spot and the near-field light spot can be brought as close as possible in the track direction. In this respect as well, high density recording can be achieved.

  In addition, since it can be built in the same plane parallel to the outflow end face of the slider, it can be manufactured using a semiconductor manufacturing technique such as a normal photolithography technique without using a special technique. . Therefore, it can be manufactured easily, mass production is possible, and the head can be made thin.

In addition , since the metal film can be formed by using the step portion in which the other end side portion of the propagation portion is inserted, a metal film having a specified length is formed on the side surface on the main magnetic pole side in the other end side portion of the propagation portion. It can be easily formed.
Therefore, the metal film having the minimum necessary length can be formed by adjusting the size of the step portion. For this reason, the light beam can be efficiently propagated using the propagation part as close as possible to the surface of the magnetic recording medium and then incident on the metal film to generate near-field light. Therefore, the propagation loss of the luminous flux can be suppressed as much as possible, the generation efficiency of near-field light can be increased, and writing can be performed with near-field light having a higher light intensity.

( 2 ) Further, in the recording head according to the present invention, a cross-sectional area perpendicular to the optical axis of the transmitted light beam gradually decreases from the one end side toward the surface of the magnetic recording medium. The first propagation part thus drawn and the second propagation connected to the first propagation part and extending in the same shape so that the cross-sectional area is constant from the connection part to the other end side And the metal film may be formed on a side surface of the second propagation part.

  In this case, the other end side part of the propagation part is a second propagation part extending in the same shape, and the metal film is formed on the side surface of the second propagation part on the main magnetic pole side. Unlike the case where the metal film is formed on the side surface that has complicated shape change, the metal film can be easily and firmly formed, and the metal film is unlikely to peel off. Accordingly, near-field light can be generated stably over a long period of time, and the writing reliability can be improved.

( 3 ) In the recording head according to the present invention, the propagation portion may be formed so that a cross section perpendicular to the optical axis is triangular.

  In this case, the light beam can be easily propagated while being collected more efficiently, and the light propagation efficiency can be increased.

( 4 ) An information recording / reproducing apparatus according to the present invention is movable in a direction parallel to the surface of the recording head according to the present invention and the magnetic recording medium, and is parallel to the surface of the magnetic recording medium. A suspension that supports the recording head while being rotatable about two axes orthogonal to each other, a light source that causes the light beam to enter the propagation portion, a pivot shaft that is disposed outside the magnetic recording medium, and the pivot And a carriage having an arm portion which is formed to be rotatable around an axis and supports the suspension.

  According to the information recording / reproducing apparatus of the present invention, since the recording head is provided, it is possible to provide a high-quality apparatus with high writing reliability and high density recording.

According to the recording head of the present invention, it is possible to easily manufacture without taking time and to make the spot center of the magnetic field spot coincide with the spot center of the near-field light spot in the traveling direction of the head. Therefore, the writing reliability is improved and high density recording can be achieved.
Further, according to the information recording / reproducing apparatus of the present invention, it is possible to provide a high-quality apparatus with high writing reliability and corresponding to high density recording.

1 is a perspective view showing an embodiment of an information recording / reproducing apparatus according to the present invention. It is a perspective view of the head gimbal assembly shown in FIG. It is a top view of the gimbal shown in FIG. It is sectional drawing along the AA line shown in FIG. FIG. 5 is an enlarged cross-sectional view around the recording head shown in FIG. 4. FIG. 6 is a cross-sectional view further enlarging the outflow end face side of the recording head shown in FIG. 5. It is sectional drawing along the BB line shown in FIG. It is the perspective view which looked at the main magnetic pole periphery from the disk side. It is a top view of the terminal board shown in FIG. It is the figure which showed the relationship between the magnetic field spot at the time of writing in a disc, and a near-field light spot. It is the figure which showed the relationship between the magnetic field curve at the time of writing in a disk, and a coercive force curve. FIG. 9 is a diagram illustrating a modification of the recording head and is a perspective view corresponding to FIG. 8. It is a figure which shows another modification of a recording head, Comprising: It is a perspective view equivalent to FIG. 8 in the state which removed the spot size converter. In FIG. 13, it is a perspective view of the state which attached the spot size converter. It is a perspective view which shows the modification of a spot size converter. FIG. 16 is a diagram showing a modification of the recording head having the spot size converter shown in FIG. 15, and is a perspective view corresponding to FIG. FIG. 6 is a diagram showing a relationship between a magnetic field spot and a near-field light spot when writing to a disk in a conventional head. FIG. 10 is a diagram showing a relationship between a magnetic field curve and a coercive force curve when writing to a disk in a conventional head. FIG. 10 is a diagram showing a relationship between a magnetic field spot and a near-field light spot when writing to a disk in another conventional head. It is the figure which showed the relationship between the magnetic field curve and the coercive force curve at the time of writing in a disk in another conventional head.

  Hereinafter, an embodiment of an information recording / reproducing apparatus according to the present invention will be described with reference to FIGS. Note that the information recording / reproducing apparatus 1 of the present embodiment is an apparatus for writing on a disk (magnetic recording medium) D having a perpendicular recording layer by a perpendicular recording method.

(Information recording / reproducing device)
As shown in FIG. 1, the information recording / reproducing apparatus 1 of the present embodiment includes a carriage 11 and a laser light source 20 that supplies a light beam L (see FIG. 6) from the base end side of the carriage 11 via a photoelectric composite wiring 33. A head gimbal assembly (HGA) 12 supported on the front end side of the carriage 11, an actuator 6 that scans and moves the head gimbal assembly 12 in the XY directions parallel to the disk surface D1 (the surface of the disk D), and a disk A spindle motor 7 that rotates D in a predetermined direction, a control unit 5 that supplies a current modulated according to information to the recording head 2 of the head gimbal assembly 12, and these components are housed inside. And a housing 9.

The housing 9 has a box-like shape having a top opening made of a metal material such as aluminum, and has a rectangular bottom portion 9a as viewed from above, and a peripheral wall erected in the vertical direction with respect to the bottom portion 9a at the periphery of the bottom portion 9a. (Not shown). And the recessed part which accommodates each component mentioned above is formed in the inner side enclosed by the surrounding wall.
In FIG. 1, the peripheral wall surrounding the housing 9 is omitted for easy understanding.

  A lid (not shown) is detachably fixed to the housing 9 so as to close the upper opening of the housing 9. The spindle motor 7 is attached to substantially the center of the bottom portion 9a, and the disc D is detachably fixed by fitting a center hole into the spindle motor 7.

The actuator 6 described above is attached to one corner of the bottom 9a outside the disk D. A carriage 11 that can rotate in a horizontal plane (XY direction) about a pivot shaft 10 is attached to the actuator 6.
The carriage 11 includes an arm portion 14 extending from the base end portion toward the tip portion (in the direction of the disk D), and a base portion 15 that supports the arm portion 14 in a cantilever manner via the base end portion. However, they are integrally formed by machining or the like.
The base portion 15 is formed in a substantially rectangular parallelepiped shape, and is supported so as to be rotatable around the pivot shaft 10. That is, the base portion 15 is connected to the actuator 6 via the pivot shaft 10, and the pivot shaft 10 is the rotation center of the carriage 11.

The arm portion 14 extends in parallel to the surface direction (XY direction) of the upper surface of the base portion 15 on the side surface 15b opposite to the side surface 15a to which the actuator 6 is attached in the base portion 15 (side surface on the opposite side of the corner portion). 3 pieces extending along the height direction (Z direction) of the base portion 15.
Specifically, the arm portion 14 is formed in a tapered shape that tapers from the proximal end portion toward the distal end portion, and is arranged so that the disk D is sandwiched between the arm portions 14. That is, the arm portions 14 and the disks D are configured to be alternately arranged, and the arm portions 14 can be moved in a direction (XY direction) parallel to the disk surface D1 by driving the actuator 6.
The carriage 11 and the head gimbal assembly 12 are retracted from the disk D by driving the actuator 6 when the rotation of the disk D is stopped.

The head gimbal assembly 12 guides the light beam L from the laser light source 20 to the recording head 2 to be described later to generate near-field light S (see FIG. 7), and uses the near-field light S to send various information to the disk D. It is to be recorded and reproduced.
As shown in FIGS. 2 to 5, the head gimbal assembly 12 of this embodiment has a function of floating the recording head 2 from the disk D. The recording head 2 and the metal material are thin plate-like. The suspension 3 is movable in the XY directions parallel to the disk surface D1, and the recording head 2 is rotatable about two axes (X axis, Y axis) that are parallel to the disk surface D1 and orthogonal to each other. That is, gimbal means 16 is provided for fixing to the lower surface of the suspension 3 so as to be twisted about the two axes.

The recording head 2 is supported between a disc D and the suspension 3 with a gimbal 17 (described later) sandwiched between the lower surface of the suspension 3.
As shown in FIGS. 5 and 6, the recording head 2 is disposed so as to face the disk D in a state where it floats a predetermined distance from the disk surface D1, and has a slider 60 having a flying surface 2a facing the disk surface D1, and a slider. 60, a spot size converter (light propagation element) 40, a recording element 41, and a reproducing element 42 are provided on the outflow end face (tip face) 60a side.

The slider 60 is disposed to face the disk D so that the outflow end surface 60a is positioned on the downstream side in the rotation direction of the disk D when the disk D is viewed from the slider 60. Further, the surface facing the outflow end surface 60a functions as an inflow end surface located upstream in the rotation direction of the disk D. Therefore, when the disk D rotates, the air generated by the rotating disk D flows along the air bearing surface 2a from the inflow end face side and then escapes from the outflow end face 60a side.
The recording head 2 floats on the disk D with the outflow end surface 60a side of the slider 60 closest to the disk surface D1. Therefore, by arranging the above components on the outflow end surface 60a side of the slider 60, these components can be brought as close to the disk surface D1 as possible, and the coercive force of the disk D can be efficiently reduced to the disk D. Is easy to write.

  By the way, in this embodiment, the recording element 41, the spot size converter 40, and the reproducing element 42 are arranged in order from the outflow end surface 60a side of the slider 60. In addition, a main magnetic pole 47 (to be described later) of the recording element 41 and a second propagation section 54 of a propagation section 50 (to be described later) of the spot size converter 40 are disposed in the same plane parallel to the outflow end surface 60 a of the slider 60. . This point will be described later in detail.

  The slider 60 is formed in a rectangular parallelepiped shape from a light transmissive material such as quartz glass, a ceramic such as AlTiC (altic), or the like. The slider 60 is supported so as to hang from the tip of the suspension 3 (see FIG. 3) via the gimbal 17 (see FIG. 3) with the air bearing surface 2a facing the disk D side.

  The reproducing element 42 is a magnetoresistive film whose electric resistance is converted according to the magnitude of the magnetic field leaking from the disk D. A bias current is supplied to the reproducing element 42 from the control unit 5 (see FIG. 1) via an electric wiring 31 described later. As a result, the control unit 5 can detect a change in the magnetic field leaking from the disk D as a change in voltage, and can reproduce a signal from the change in voltage.

  The recording element 41 is connected to the auxiliary magnetic pole 45 located on the outflow end surface 60 a side of the slider 60 and the auxiliary magnetic pole 45 via the magnetic circuit 46, and a recording magnetic field perpendicular to the disk D is transmitted between the auxiliary magnetic pole 45. A main magnetic pole 47 to be generated and a coil 48 wound around the magnetic circuit 46 in a spiral shape around the magnetic circuit 46 are provided.

  Both the magnetic poles 45 and 47 and the magnetic circuit 46 are formed 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 48 is arranged so that there is a gap between adjacent coil wires, between the magnetic circuit 46 and between the magnetic poles 45 and 47 so as not to be short-circuited. Molded. That is, the magnetic poles 45 and 47, the magnetic circuit 46 and the coil 48 are supported by the insulating layer 49. The coil 48 is supplied with a current modulated in accordance with information from the control unit 5.

Incidentally, the coil 48 is formed at a position close to one side surface of the slider 60 in the lateral width direction of the slider 60 parallel to the track direction (X direction) of the disk D, as shown in FIGS. Yes. On the other hand, the main magnetic pole 47 and the auxiliary magnetic pole 45 are formed at positions closer to the center line C in the width direction of the slider 60 than the coil 48, and the head traveling direction (Y direction) with the insulating layer 49 interposed therebetween. It is formed so as to face each other with a gap. At this time, the main magnetic pole 47 and the auxiliary magnetic pole 45 are designed so that the end surfaces facing the disk D are flush with the flying surface 2 a of the slider 60.
In FIG. 7, the auxiliary magnetic pole 45 is not shown.

  The spot size converter 40 includes a propagation part 50 that propagates a light beam L incident from one end side while condensing the light beam L toward the other end side facing the disk surface D1, and a cladding (not shown) that confine the propagation part 50 inside. And is fixed adjacent to the recording element 41 so as to be located on the trailing edge side of the recording element 41 as described above.

  The propagation portion 50 extends along the outflow end surface 60a of the slider 60, and is disposed on the horizontal width center line C in a state where one end side faces the slider 60 and the other end side faces the disk D. ing. The propagation unit 50 is configured integrally with a first propagation unit 53 and a second propagation unit 54.

The first propagation part 53 is perpendicular to the longitudinal direction (Z direction) of the first propagation part 53 from the one end side to the disk D (perpendicular to the optical axis of the propagated light beam L), that is, perpendicular to the outflow end surface 60a of the slider 60. This is a portion formed by drawing so that the cross-sectional area in the surface to be gradually reduced, and thus the light beam L can be propagated while condensing.
The second propagation part 54 is connected to the first propagation part 53 and extends in the same shape from the connection part P (see FIG. 7) to the other end side so that the cross-sectional area is constant. It functions as the other end side portion of the entire propagation part 50.

In addition, the 1st propagation part 53 and the 2nd propagation part 54 are formed so that it may become a cross-sectional square shape. Further, the end surface of the second propagation portion 54 is designed to be flush with the air bearing surface 2 a of the slider 60.
The first propagation part 53 and the second propagation part 54 are both made of a material having a refractive index higher than the refractive index of the cladding, and are cores that guide the light beam L under total reflection conditions due to the difference in refractive index with the cladding. ing.
A clad (not shown) is in close contact with the first propagation part 53 and the second propagation part 54, which are cores, to confine the first propagation part 53 inside. At this time, the clad may be formed so as to cover the end face of the second propagation portion 54 or may be formed so as to be exposed.

An example of a combination of materials used as the clad and the core is described, for example, a combination in which the core is formed of quartz (SiO ₂ ) and the clad is formed of fluorine-doped quartz. In this case, when the wavelength of the light beam L is 400 nm, the refractive index of the core is 1.47 and the refractive index of the cladding is less than 1.47, which is a preferable combination. A combination in which the core is formed of quartz doped with germanium and the cladding is formed of quartz (SiO ₂ ) is also conceivable. In this case, when the wavelength of the light beam L is 400 nm, the refractive index of the core is larger than 1.47 and the refractive index of the cladding is 1.47, which is also a preferable combination.

In particular, as the refractive index difference between the core and the clad increases, the force for confining the light beam L in the core increases. Therefore, tantalum oxide (Ta ₂ O ₅ : the refractive index is 2.16 when the wavelength is 550 nm) in the core. More preferably, the difference in refractive index between the two is increased by using quartz for the cladding. In addition, when the luminous flux L in the infrared region is used, it is also effective to form the core with silicon (Si: refractive index is about 4) which is a material transparent to infrared light.

Incidentally, at least the second propagation portion 54 of the propagation portion 50 described above is partially buried in the insulating layer 49 of the recording element 41 by the thickness T of the main magnetic pole 47 as shown in FIG. Thereby, the main magnetic pole 47 and the second propagation part 54 are arranged so as to be arranged at a minute interval in the same plane parallel to the outflow end surface 60 a of the slider 60.
Then, near-field light S is generated on the side surface 54 a on the main magnetic pole 47 side in the second propagation part 54 by excitation of surface plasmons from the light flux L propagated by the first propagation part 53 and the second propagation part 54. A metal film (for example, a gold film) 55 is formed so as to fill the minute gap.

  The metal film 55 is formed on the side surface 54a of the second propagation part 54 without using a clad. Therefore, the light flux L propagated by the second propagation part 54 is incident on the metal film 55 without loss, and near-field light S is locally generated on the end face side of the metal film 55 by excitation of the surface plasmon.

As shown in FIGS. 2 to 5, the lower surface of the slider 60 is the air bearing surface 2a facing the disk surface D1 as described above. The air bearing surface 2a is a surface that generates pressure for ascending from the viscosity of the air flow generated by the rotating disk D, and is called an ABS (Air Bearing Surface).
Specifically, the slider 60 is designed to float in an optimum state by adjusting the positive pressure for separating the slider 60 from the disk surface D1 and the negative pressure for attracting the slider 60 to the disk surface D1. Has been.
The slider 60 receives a force that rises from the disk surface D1 by the flying surface 2a, and also receives a force that is pressed against the disk D by the suspension 3. The slider 60 floats from the disk surface D1 due to the balance of both forces.

  As shown in FIGS. 2 and 3, the suspension 3 includes a base plate 22 formed in a substantially square shape in a top view, and a load beam having a substantially triangular shape in a plan view connected to the distal end side of the base plate 22 via a hinge plate 23. 24.

The base plate 22 is made of a thin metal material such as stainless steel, and an opening 22a penetrating in the thickness direction is formed on the base end side. And the base plate 22 is being fixed to the front-end | tip of the arm part 14 through this opening 22a.
On the lower surface of the base plate 22, the sheet-like hinge plate 23 made of a metal material such as stainless steel is disposed. The hinge plate 23 is a flat plate material formed over the entire lower surface of the base plate 22, and the tip portion thereof is an extension portion 23 a extending from the tip of the base plate 22 along the longitudinal direction of the base plate 22. Is formed. Two extending portions 23 a extend from both end portions in the width direction of the hinge plate 23, and the load beam 24 is connected to the tip portion.

The load beam 24 is formed of a thin metal material such as stainless steel like the base plate 22, and the base end thereof is connected to the hinge plate 23 with a gap between the base plate 22 and the tip end of the base plate 22. .
As a result, the suspension 3 bends about between the base plate 22 and the load beam 24 and is easily bent in the Z direction perpendicular to the disk surface D1.

A flexure 25 is provided on the suspension 3.
The flexure 25 is a sheet-shaped member made of a metal material such as stainless steel, and is configured to be able to bend and deform in the thickness direction by being formed into a sheet shape. The flexure 25 is fixed to the distal end side of the load beam 24, and has a gimbal 17 whose outer shape is formed in a substantially pentagonal shape when viewed from above and a width narrower than the gimbal 17. And a support 18 extending along the axis.

The gimbal 17 is formed so as to slightly warp in the thickness direction from the vicinity of the middle to the tip toward the disk surface D1. Then, the warped end is fixed to the load beam 24 from the base end to substantially the middle so that the front end does not come into contact with the load beam 24. Further, a cutout portion 26 is formed on the front end side of the floating gimbal 17 so that the periphery thereof is wound in a U shape. The portion surrounded by the cutout portion 26 is cantilevered by a connecting portion 17a. A pad portion 17b supported in a shape is formed.
That is, the pad portion 17b is formed to project from the distal end side to the proximal end side of the gimbal 17 by the connecting portion 17a, and is provided with a notch 26 around the periphery.

  Accordingly, the pad portion 17 b is easily bent in the thickness direction of the gimbal 17, and the angle is adjusted so that only the pad portion 17 b is parallel to the lower surface of the suspension 3. The above-described recording head 2 is placed and fixed on the pad portion 17b. That is, the recording head 2 is hung from the load beam 24 via the pad portion 17b.

As shown in FIGS. 3 and 4, a pad portion 17 b and a protruding portion 19 that protrudes toward the approximate center of the recording head 2 are formed at the tip of the load beam 24. The tip of the projection 19 is rounded. The protrusion 19 comes into point contact with the surface (upper surface) of the pad portion 17b when the recording head 2 floats to the load beam 24 side by the wind pressure received from the disk D.
That is, the protrusion 19 supports the recording head 2 via the pad portion 17b of the gimbal 17 and applies a load to the recording head 2 toward the disk surface D1 (in the Z direction). Yes. A contact point (support point) between the protrusion 19 and the pad 17 b is a load point of the recording head 2 by the protrusion 19.
The protrusions 19 and the gimbal 17 having the pad portions 17b constitute the gimbal means 16.

  The support 18 shown in FIG. 2 is in the form of a sheet integrally formed with the gimbal 17 and extends on the suspension 3 toward the arm portion 14. That is, the support 18 is configured to follow the deformation of the suspension 3 when the suspension 3 is deformed. Further, the support 18 is drawn from the arm portion 14 to the side surface until reaching the base portion 15 of the carriage 11.

As shown in FIGS. 1 and 9, the terminal board 30 is disposed on the side surface 15 c of the base portion 15 of the carriage 11. The terminal board 30 serves as a relay point when the control unit 5 provided in the housing 9 and the recording head 2 are electrically connected, and various control circuits (not shown) are formed on the surface thereof. Has been.
The control unit 5 and the terminal board 30 are electrically connected by a flexible flat cable 4, while the terminal board 30 and the recording head 2 are connected by an electric wiring 31. Three sets of the electrical wirings 31 are provided corresponding to the recording heads 2 provided on each carriage 11, and signals output from the control unit 5 via the flat cable 4 are recorded via the electrical wirings 31. It is output to the head 2.

  On the terminal substrate 30, the laser light source 20 that supplies the light beam L toward the spot size converter 40 of the recording head 2 is disposed. The laser light source 20 receives a signal output from the control unit 5 via the flat cable 4 and emits a light beam L based on this signal, and corresponds to the recording head 2 provided in each arm unit 14. Then, three are arranged along the height direction (Z direction) of the base 15. An optical waveguide 32 that guides the emitted light beam L to the recording head 2 is connected to the emission side of each laser light source 20.

As shown in FIGS. 2 and 3, the optical waveguide 32 and the electric wiring 31 are integrally formed between the laser light source 20 and the recording head 2 from the base end side to the tip end. The wiring 33 is configured.
The photoelectric composite wiring 33 is routed on the arm portion 14 from the surface of the terminal substrate 30 through the side surface of the arm portion 14. Specifically, the photoelectric composite wiring 33 is arranged on the support 18 of the flexure 25 on the arm portion 14 and the suspension 3, and reaches the tip of the suspension 3 with the support 18 sandwiched therebetween. Has been routed.

The photoelectric composite wiring 33 branches into an electrical wiring 31 and an optical waveguide 32 at the tip of the suspension 3, that is, at an intermediate position of the gimbal 17.
Specifically, the optical waveguide 32 extends along the longitudinal direction of the gimbal 17 from a branch point on the distal end side of the photoelectric composite wiring 33, and flows into the recording head 2 across the notch portion 26 of the gimbal 17. Connected directly to the end. The optical waveguide 32 is separated from the lower surface of the gimbal 17 at the branch point of the photoelectric composite wiring 33, and bridges between the pad portion 17 b and the gimbal 17 as it goes from the branch point toward the inflow end side of the recording head 2. It extends in a slightly floating state.
That is, on the lower surface of the gimbal 17, the optical waveguide 32 extends substantially linearly (the radius of curvature is approximately infinite), and the inflow end side of the recording head 2 from the center in the width direction (X direction) of the recording head 2. Has been routed to.

  On the other hand, at the branch point, the electric wiring 31 is bent toward the outer peripheral portion of the gimbal 17 and is routed from the outer peripheral portion of the gimbal 17, that is, from the outside of the notch portion 26. The electric wiring 31 routed from the outside of the notch 26 passes through the connecting portion 17a and is connected to the outflow end surface 60a side of the recording head 2. That is, the electric wiring 31 is directly connected from the outside of the recording head 2 to the reproducing element 42 and the recording element 41 provided on the outflow end surface 60 a side of the slider 60.

The constituent material of the optical waveguide 32 can be the same material as the core and clad of the spot size converter 40 described above, but in the present embodiment, the following resin materials are preferably used. ing.
For example, a combination in which the core 32a is formed with a thickness of 3 to 10 μm using PMMA (methyl methacrylate resin) and the clad 32b is formed with a thickness of several tens of μm using a fluorine-containing polymer is conceivable. Further, both the core 32a and the clad 32b are made of epoxy resin (for example, core refractive index 1.522 to 1.523, clad refractive index 1.518 to 1.519), or made of fluorinated polyimide. Is also possible. In this case, it is preferable to increase the difference in refractive index between the two by adjusting the blending of the resin materials constituting the core 32a and the clad 32b. For example, in the case of fluorinated polyimide, the refractive index can be controlled by adjusting the fluorine content or by irradiating energy such as radiated light. Thus, by using a resin material as the constituent material of the optical waveguide 32, the photoelectric composite wiring 33 can be manufactured by a semiconductor process.

  By the way, as shown in FIG. 6, the front end surface of the optical waveguide 32 is a mirror surface 35 cut obliquely, and the direction of the light beam L introduced by the laser light source 20 changes by approximately 90 degrees. Is reflected. As a result, the light beam L reflected by the mirror surface 35 is introduced into the propagation unit 50 constituting the spot size converter 40 of the recording head 2. The mirror surface 35 may be configured such that a reflecting plate made of aluminum or the like is formed in an area including at least the core 32a by vapor deposition or the like.

(Information recording and playback method)
Next, a procedure for recording and reproducing various types of information on the disc D by the information recording / reproducing apparatus 1 configured as described above will be described.

  First, the spindle motor 7 is driven to rotate the disk D in a predetermined direction. Next, the actuator 6 is operated to rotate the carriage 11 about the pivot shaft 10 as a rotation center, and the head gimbal assembly 12 is scanned in the XY directions via the carriage 11. As a result, the recording head 2 can be positioned at a desired position on the disk D as shown in FIG.

At this time, the recording head 2 is supported by the suspension 3 and pressed against the disk D side with a predetermined force. At the same time, the recording head 2 receives the force of flying by using the flying surface 2a under the influence of the wind pressure generated by the rotating disk D. Due to the balance of both forces, the recording head 2 floats away from the disk D.
Moreover, since the recording head 2 receives the wind pressure and is pushed toward the suspension 3, the pad portion 17 b of the gimbal 17 that fixes the recording head 2 and the protrusion 19 formed on the suspension 3 are in point contact. The floating force is transmitted to the suspension 3 through the protrusions 19 and acts to bend the suspension 3 in the Z direction perpendicular to the disk surface D1. Thereby, the recording head 2 floats as described above.

Here, when recording information, the control unit 5 operates the laser light source 20 and supplies a current modulated according to the information to the coil 48 to operate the recording element 41.
When the laser light source 20 is activated, the light beam L is incident on the optical waveguide 32. Then, the light beam L travels toward the tip side in the core 32a of the optical waveguide 32, and is then reflected by the mirror surface 35 and introduced into the propagation part 50 of the spot size converter 40, as shown in FIG. Is done. The light beam L introduced into the propagation part 50 is repeatedly reflected from the interface with the clad (not shown) toward the other end side located on the disk D side, while repeating the first propagation part 53 and the second propagation part 54. Are propagated in order.

  At this time, since the first propagation part 53 is formed by drawing from one end side to the other end side, the light flux L can be propagated while gradually condensing. Therefore, the light beam L is gradually narrowed down and propagates through the second propagation portion 54 in a state where the spot size is sufficiently small, and then enters the metal film 55. Thus, the near-field light S can be generated by exciting the surface plasmon from the propagated light beam L using the metal film 55, and can be emitted to the outside. Then, the disk D is locally heated by the near-field light S, and the coercive force is temporarily reduced.

  On the other hand, when a current is supplied to the coil 48 by the control unit 5, a current magnetic field is generated in the magnetic circuit 46 by the principle of an electromagnet, so that the disk D is interposed between the main magnetic pole 47 and the auxiliary magnetic pole 45. A perpendicular recording magnetic field can be generated.

  As a result, information can be recorded by a hybrid magnetic recording method in which the near-field light S generated by the metal film 55 and the recording magnetic field generated by the recording element 41 cooperate. In addition, since the recording is performed by the vertical recording method, it is difficult to be affected by the thermal fluctuation phenomenon and the like, and stable recording can be performed. Therefore, writing reliability can be improved.

Next, when reproducing the information recorded on the disk D, the reproducing element 42 receives a magnetic field leaking from the disk D, and the electric resistance changes according to the magnitude. Therefore, the voltage of the reproducing element 42 changes. Thereby, the control unit 5 can detect a change in the magnetic field leaking from the disk D as a change in voltage. And the control part 5 can reproduce | regenerate information by reproducing | regenerating a signal from the change of this voltage.
As described above, various kinds of information can be recorded on and reproduced from the disk D using the recording head 2.

  In particular, according to the recording head 2 of the present embodiment, the main magnetic pole 47 and the second propagation portion 54 on which the metal film 55 is formed are arranged in the same plane parallel to the outflow end surface 60 a of the slider 60. Therefore, as shown in FIG. 8, the main magnetic pole 47 and the second propagation part 54 are aligned along the direction orthogonal to the head traveling direction (Y direction), that is, along the track direction (X direction) of the disk D. Can be arranged. Accordingly, the main magnetic pole 47 and the metal film 55 can be similarly arranged along the track direction (X direction) of the disk D.

Therefore, as shown in FIG. 10, the magnetic field spot SP1 of the recording magnetic field and the near-field light spot SP2 can be aligned in the track direction (X direction), and the spot center G1 of the magnetic field spot SP1 and the near-field light S It is possible to make the spot center G2 coincide with the traveling direction (Y direction) of the head.
Accordingly, as shown in FIG. 11, the peak of heating (coercive force curve C1) is applied to the magnetic domain of the target recording track without affecting the magnetic domain of another recording track adjacent to the track direction (X direction) as much as possible. And the magnetic field peak (the peak of the magnetic field curve C2) coincide with the traveling direction of the head (Y direction), and heating and magnetic field application can be performed locally.

  Therefore, the writing reliability can be improved and high density recording can be achieved. Moreover, since the metal film 55 is formed on the side surface 54a on the main magnetic pole 47 side in the second propagation part 54, as shown in FIG. 10, the magnetic field spot SP1 and the near-field light spot SP2 are moved in the track direction (X Direction) as close as possible. In this respect as well, high density recording can be achieved.

Further, as shown in FIGS. 7 and 8, the second propagation part 54 extends in the same shape from the connecting portion P to the first propagation part 53 toward the end surface, so that the shape changes complicatedly. Unlike the case where the metal film 55 is formed on the side surface 54a, the metal film 55 can be easily and firmly formed, and the metal film 55 is unlikely to peel off.
Therefore, the near-field light S can be generated stably over a long period of time, and the writing reliability can be improved.

  In addition, since the recording head 2 can be manufactured in the same plane parallel to the outflow end surface 60a of the slider 60, a normal photolithography technique and etching technique can be used without manufacturing a special technique. The manufacturing can be performed in the conventional process while utilizing the semiconductor technology such as the above. Therefore, it can be manufactured easily, mass production is possible, and the recording head 2 itself can be made thin.

  Since the information recording / reproducing apparatus 1 of the present embodiment includes the recording head 2 described above, the information recording / reproducing apparatus 1 has high writing reliability and can be a high-quality apparatus compatible with high-density recording.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above embodiment, the air floating type information recording / reproducing apparatus 1 in which the slider 60 is levitated has been described as an example. However, the present invention is not limited to this case. The slider 60 may be in contact. That is, the recording head 2 of the present invention may be a contact slider type head. Even in this case, the same effects can be achieved.

In the above-described embodiment, the configuration in which the head gimbal assembly 12 is provided only on one side of the arm unit 14 has been described. However, both surfaces of the arm unit 14 inserted between the disks D face each disk D. In this way, a configuration in which the head gimbal assembly 12 is provided is also possible.
In this case, information can be recorded / reproduced on the disk surface D1 facing each recording head 2 by each recording head 2 of the head gimbal assembly 12 provided on both sides of the arm portion 14. That is, since information on two disks D can be recorded and reproduced by one arm unit 14, the recording capacity of the information recording / reproducing apparatus 1 can be increased and the apparatus can be downsized.

  In the above embodiment, the laser light source 20 for introducing the light beam L into the spot size converter 40 is arranged on the terminal board 30 attached to the base portion 15 of the carriage 11. However, the present invention is limited to this position. It is not a thing. For example, it may be disposed on the upper surface of the slider 60 and integrally mounted on the recording head 2. This is more preferable because the optical waveguide 32 does not need to be routed from the carriage 11 and the movement of the slider 60 at the time of flying is not easily inhibited by the optical waveguide 32.

In the above embodiment, as shown in FIG. 12, the metal film 55 formed on the side surface 54 a on the main magnetic pole 47 side in the second propagation portion 54 is not caught by the thickness T of the main magnetic pole 47, and the second propagation is performed. You may form to the extent equivalent to thickness T1 of the part 54. FIG.
However, in this case, it is preferable to form the metal film 55 so as to be tapered toward the disk D. By doing so, the end face of the metal film 55 facing the disk D can be made as small as possible, and the near-field light S can be generated locally with a higher light intensity.
In addition, as shown in FIG. 12, it is preferable to form the metal film 55 so as to taper while smoothly curving so that corners do not appear in the outer shape. By doing so, the excited surface plasmon can be smoothly propagated to the end face without being obstructed by the corner portion, and the near-field light S can be generated more efficiently.

  Further, in the above-described embodiment, the step portion 49a is formed in the insulating layer 49 as shown in FIG. 13, and the second propagation portion 54 is inserted into the step portion 49a as shown in FIG. The portion 54 may be disposed in the same plane as the main magnetic pole 47, and the metal film 55 may be formed in the stepped portion 49 a located between the main magnetic pole 47 and the second propagation portion 54.

  In this case, since the metal film 55 can be formed using the stepped portion 49a into which the second propagation portion 54 has entered, the prescribed length M is formed on the side surface 54a on the main magnetic pole 47 side in the second propagation portion 54. The metal film 55 can be easily formed. Therefore, the metal film 55 having the minimum necessary length can be formed only by adjusting the size of the stepped portion 49a. Therefore, after the light beam L is efficiently propagated to the position as close as possible to the disk surface D1 by using the propagation part 50, it can be incident on the metal film 55 to generate the near-field light S. Therefore, the propagation loss of the light beam L can be suppressed as much as possible, the generation efficiency of the near-field light S can be increased, and writing can be performed with the near-field light S with higher light intensity.

  In this case, as a method for forming the metal film 55, for example, a sacrificial layer is formed obliquely with respect to the stepped portion 49a, then gold or the like is formed on the entire surface, and then the sacrificial layer is lifted off. Thus, as shown in FIG. 13, the metal film 55 can be easily formed using the side surface of the stepped portion 49a.

Further, in the above embodiment, as shown in FIG. 15, the propagation part 50 may be formed so that the cross section perpendicular to the outflow end surface 60 a of the slider 60 has a triangular shape.
In this case, the light flux L can be easily propagated while being collected more efficiently, and the light propagation efficiency can be increased. Also, as shown in FIG. 16, the side surface 54 a on the main magnetic pole 47 side of the second propagation portion 54 becomes an inclined surface with respect to the main magnetic pole 47, so that the metal film 55 can be formed more easily. Furthermore, it becomes easy to raise the coupling efficiency in the connection part P (refer FIG. 15) of the 1st propagation part 53 and the 2nd propagation part 54. FIG.

L ... Light flux D ... Disk (magnetic recording medium)
D1 ... disk surface (surface of magnetic recording medium)
DESCRIPTION OF SYMBOLS 1 ... Information recording / reproducing apparatus 2 ... Recording head 3 ... Suspension 20 ... Laser light source (light source)
DESCRIPTION OF SYMBOLS 10 ... Pivot shaft 11 ... Carriage 14 ... Arm part 40 ... Spot size converter (light propagation element)
DESCRIPTION OF SYMBOLS 41 ... Recording element 45 ... Auxiliary magnetic pole 47 ... Main magnetic pole 49 ... Insulating layer 49a ... Step part of insulating layer 50 ... Propagation part 53 ... 1st propagation part 54 ... 2nd propagation part (the other end side part of a propagation part)
55 ... Metal film 60 ... Slider 60a ... Outflow end face of slider

Claims (4)

A slider disposed opposite to the surface of the magnetic recording medium rotating in a certain direction with the outflow end face facing downstream in the rotation direction of the magnetic recording medium;
A light propagation element disposed on the outflow end face side of the slider and having a propagation part that propagates the light beam incident from one end side while converging toward the other end side facing the surface of the magnetic recording medium;
A recording element disposed on the outflow end face side of the slider, having a main magnetic pole and an auxiliary magnetic pole, and generating a recording magnetic field between the magnetic poles,
The main magnetic pole and at least the other end portion of the propagation part are arranged in the same plane parallel to the outflow end face of the slider,
A metal film that generates near-field light by excitation of surface plasmons from the propagated light flux is formed on the side surface on the main pole side in the other end side portion of the propagation portion ,
The recording element has an insulating layer that supports the main magnetic pole,
The insulating layer is formed with a stepped portion that allows the other end side portion of the propagation portion to enter and arrange the other end side portion in the same plane as the main magnetic pole,
The recording film according to claim 1, wherein the metal film is formed in the stepped portion located between the main magnetic pole and the other end portion of the propagation portion . The recording head according to claim 1 ,
The propagation part is
A first propagation part formed by drawing so that a cross-sectional area perpendicular to the optical axis of the propagated light beam gradually decreases from the one end side toward the surface of the magnetic recording medium;
A second propagation part that is connected to the first propagation part and extends in the same shape so that the cross-sectional area is constant from the connection part to the other end side,
The recording head, wherein the metal film is formed on a side surface of the second propagation part. The recording head according to claim 2 , wherein
The recording head according to claim 1, wherein the propagation part is formed so that a cross section perpendicular to the optical axis has a triangular shape. The recording head according to any one of claims 1 to 3 ,
A suspension that is movable in a direction parallel to the surface of the magnetic recording medium, and that supports the recording head in a state of being rotatable about two axes parallel to the surface of the magnetic recording medium and orthogonal to each other;
A light source that causes the light beam to enter the propagation portion;
A pivot shaft disposed outside the magnetic recording medium;
An information recording / reproducing apparatus comprising: a carriage formed to be rotatable around the pivot shaft and having an arm portion for supporting the suspension.

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