JP5854403B2 - Near-field optical head, method for manufacturing near-field optical head, and information recording / reproducing apparatus - Google Patents

Description

The present invention relates to a near-field optical head, a method for manufacturing a near-field optical head, and an information recording / reproducing apparatus.
This application claims priority on March 10, 2010 based on Japanese Patent Application No. 2010-053699 for which it applied to Japan, and uses the content for it here.

  In recent years, the recording density of information within a single recording surface has increased as the capacity of hard disks and the like in computer equipment has increased. For example, in order to increase the recording capacity per unit area of the magnetic disk, it is necessary to increase the surface recording density. However, as the recording density increases, the recording area occupied by one bit on the recording medium decreases. When this bit size is reduced, the energy of 1-bit information becomes close to the thermal energy at room temperature, and the recorded information is reversed or disappears due to thermal fluctuations, etc. Will occur.

  In the in-plane recording method that has been generally used, the magnetism is recorded so that the direction of magnetization is in the in-plane direction of the recording medium. In this method, the recorded information is lost due to the thermal demagnetization described above. Is likely to occur. Therefore, in order to solve such a problem, a shift is being made to a perpendicular recording method in which a magnetization signal is recorded in a direction perpendicular to the recording medium. This method is a method for recording magnetic information on the principle of bringing a single magnetic pole closer to a recording medium. According to this method, the recording magnetic field is directed substantially perpendicular to the recording film. Information recorded by a perpendicular magnetic field is easy to maintain in energy stability because it is difficult for the N pole and the S pole to form a loop in the recording film surface. Therefore, this perpendicular recording method is more resistant to thermal demagnetization than the in-plane recording method.

  However, recent recording media are required to have a higher density in response to the need to record and reproduce a larger amount and higher density information. For this reason, in order to minimize the influence of adjacent magnetic domains and thermal fluctuations, those having a strong coercive force have begun to be adopted as recording media. For this reason, it is difficult to record information on a recording medium even in the above-described perpendicular recording system.

  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 including a hybrid magnetic recording type recording / reproducing head for performing writing on a recording medium 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 increase the recording bit density exceeding that of the conventional information recording / reproducing apparatus.

  A recording / reproducing head using near-field light (hereinafter referred to as a near-field light head) includes a recording magnetic field generator having a main magnetic pole and an auxiliary magnetic pole, and a near-field light generated by receiving laser light from an optical fiber. A field light generation layer (see, for example, Patent Documents 1 and 2). Each of these components is laminated in the order of the auxiliary magnetic pole, the main magnetic pole, and the near-field light generating layer on the side surface of the slider fixed to the tip of the beam while being covered with the coating layer. The covering layer includes a layer that serves as an optical waveguide for guiding the laser light emitted from the optical fiber to the near-field light generating layer, and has a multilayer structure in which layers formed of different materials are stacked. ing.

  When the near-field light head configured in this way is used, various information is recorded on the recording medium by generating a near-field light and simultaneously applying a recording magnetic field. That is, when laser light is irradiated from the optical fiber, the laser light propagates through the optical waveguide of the coating layer and then reaches the near-field light generating layer. Then, in the near-field light generating layer, the internal free electrons are uniformly vibrated by the electric field of the laser light, so that the plasmon is excited to generate near-field light at the tip portion. As a result, the magnetic recording layer of the recording medium is locally heated by near-field light, and the coercive force temporarily decreases. Simultaneously with the irradiation of the laser beam, a recording magnetic field is locally applied to the magnetic recording layer of the recording medium adjacent to the main magnetic pole by supplying a drive current to the recording magnetic field generator. Thereby, various types of information can be recorded on the magnetic recording layer whose coercive force has temporarily decreased. That is, recording on a recording medium can be performed by cooperation between the thermal assist of the near-field light and the magnetic field. The slider provided with the near-field optical head is configured to keep the distance from the recording medium at an appropriate distance while receiving the wind pressure generated by the rotation of the recording medium and floating on the recording medium. .

Japanese Unexamined Patent Publication No. 2007-164935 Japanese Unexamined Patent Publication No. 2007-164936

  By the way, the structure of the conventional near-field light head has a shape in which a covering layer and a near-field light generating layer are laminated on the recording magnetic field generating portion. That is, in the case of manufacturing a conventional near-field light head, a recording magnetic field generating portion is first formed on the side surface of the slider, and then a coating layer (optical waveguide portion) and a near-field light generating layer (near-field light generating element portion). ) Are sequentially formed. Therefore, the conventional near-field optical head has a problem that it is larger than the existing magnetic recording head, the number of manufacturing processes is increased, and the production efficiency is lowered.

  Further, when the near-field optical head is increased in size, the moment of inertia generated in the beam when the slider provided with the near-field optical head is moved increases, and the distance from the recording medium while the slider is levitated with respect to the recording medium. It becomes difficult to hold the at an appropriate distance. That is, there is a problem that the position control of the slider becomes unstable.

  Therefore, the present invention has been made in view of the above-described circumstances, and can improve the production efficiency and reduce the size of the near-field optical head, the near-field optical head manufacturing method, and information. An object is to provide a recording / reproducing apparatus.

In order to solve the above problems, the present invention provides the following means.
(1) A near-field optical head according to one aspect of the present invention is disposed on the leading end side in the extending direction of a slider disposed opposite to the surface of a magnetic recording medium rotating in a fixed direction, and generates a recording magnetic field. An optical waveguide part that propagates a light beam toward the magnetic recording medium; a near-field light generating element part that generates near-field light from the light beam; and an insulating layer that constitutes the optical waveguide part The recording magnetic field generator is connected to the auxiliary magnetic pole through a magnetic circuit, and generates a recording magnetic field for the magnetic recording medium between the auxiliary magnetic pole and the magnetic pole; A coil wound around the magnetic circuit around the circuit; and the auxiliary magnetic pole, the near-field light generating element portion, and the main magnetic pole in this order on the front end surface in the extending direction of the slider Of the optical waveguide section A, the gradually reduced width toward the magnetic recording medium side, and the coil and the near-field light generating element is formed on the same plane.

  According to this configuration, at the time of manufacturing the near-field light head, at least a part of the recording magnetic field generation unit and the near-field light generation element unit can be formed simultaneously. Therefore, the manufacturing process can be simplified and the production efficiency can be improved. Further, the near-field light head can be reduced in size by simultaneously forming at least a part of the recording magnetic field generating portion and the near-field light generating element portion. As a result, the position control of the slider provided with the near-field optical head can be stabilized, and a large amount of high-density information can be recorded and reproduced. Furthermore, since it becomes easy to position at least a part of the recording magnetic field generation unit formed on the same plane and the near-field light generation element unit, a near-field optical head with high accuracy and improved yield is provided. be able to.

  According to this configuration, the coil and the near-field light generating element portion can be formed at the same time, and the size can be reduced. Further, if the coil and the near-field light generating element portion are formed of the same material, the manufacturing process can be simplified and the production efficiency can be improved. In addition, since the coil and the near-field light generating element section are arranged on the same plane, it is possible to provide a near-field light head that facilitates positioning with respect to each other, is highly accurate, and has improved yield. .

( 2 ) In the near-field light head according to (1), the near-field light generating element unit generates a plasmon from the luminous flux, and a near-field light that generates the near-field light from the plasmon. You may employ | adopt the structure provided with the generating part.

  According to this configuration, it is possible to provide a near-field light head capable of generating near-field light with high energy efficiency in the near-field light generating element unit.

( 3 ) Further, the method for manufacturing a near-field optical head according to another aspect of the present invention is arranged on the leading end side in the extending direction of the slider arranged to face the surface of the magnetic recording medium rotating in a fixed direction, and the recording magnetic field A near-field optical head comprising: a recording magnetic field generating unit that generates a light; an optical waveguide unit that propagates a light beam toward the magnetic recording medium; and a near-field light generating element unit that generates near-field light from the light beam In the manufacturing method, a step of forming an auxiliary magnetic pole of the recording magnetic field generating unit and one end of a magnetic circuit made of a magnetic material on a substrate to be the slider, and a step of forming a first insulating layer on the substrate And a step of forming a recess at a location where the core of the optical waveguide section and the coil of the recording magnetic field generation section are provided on the first insulating layer, and the core of the optical waveguide section among the recesses In the area A step of arranging a waveguide member; and forming the near-field light generating element portion by forming a conductive material on the magnetic recording medium side end portion of the concave portion configured as the optical waveguide portion. A step of forming a coil by forming a conductive material in a region configured as the coil, a step of forming a second insulating layer on the first insulating layer, the first insulating layer, and Forming a through hole communicating with one end of the magnetic circuit in the second insulating layer; arranging the magnetic material in the through hole; and a position corresponding to the through hole on the second insulating layer Forming the other end of the magnetic circuit made of the magnetic material, and forming the main magnetic pole of the recording magnetic field generating portion at a position facing the auxiliary magnetic pole on the second insulating layer. It is characterized by .

  According to this configuration, when manufacturing the near-field light head, the coil of the recording magnetic field generation unit and the near-field light generation element unit can be formed simultaneously. Therefore, the manufacturing process can be simplified and the production efficiency can be improved. Further, by forming the coil and the near-field light generating element portion at the same time, the thickness of the near-field light head in the stacking direction can be reduced, and the near-field light head can be miniaturized. As a result, the position control of the slider provided with the near-field optical head can be stabilized, and a large amount of high-density information can be recorded and reproduced. Furthermore, since the positioning between the coil formed on the same plane and the near-field light generating element portion is facilitated, a near-field light head with high accuracy and improved yield can be provided.

  In addition, the method for manufacturing a near-field optical head according to the present invention includes a recording magnetic field generating unit that is disposed on the leading end side in the extending direction of a slider disposed to face the surface of a magnetic recording medium that rotates in a certain direction, and generates a recording magnetic field. In the method of manufacturing a near-field light head, comprising: an optical waveguide portion that propagates a light beam toward the magnetic recording medium side; and a near-field light generating element portion that generates near-field light from the light beam. Forming a main magnetic pole of the recording magnetic field generating unit made of a magnetic material and one end of a magnetic circuit on the substrate to be formed, forming a first insulating layer on the substrate, and in the optical waveguide unit Forming a conductive material in a position corresponding to the end portion on the magnetic recording medium side, and simultaneously forming a conductive material in a region configured as a coil of the recording magnetic field generating unit; and light A step of patterning a shape of the core of the optical waveguide unit and the coil at a location where the core of the waveguide unit and the coil are provided; and the near-field light generating element unit by etching the conductive material using the patterning And forming the coil, forming a second insulating layer on the first insulating layer, and penetrating the first insulating layer and the second insulating layer into one end of the magnetic circuit. Forming a hole; arranging the magnetic material in the through hole; and forming the other end of the magnetic circuit made of the magnetic material at a position corresponding to the through hole on the second insulating layer. And a step of forming an auxiliary magnetic pole of the recording magnetic field generating portion at a position facing the main magnetic pole on the second insulating layer.

  According to this configuration, when manufacturing the near-field light head, the coil of the recording magnetic field generation unit and the near-field light generation element unit can be formed simultaneously. Therefore, the manufacturing process can be simplified and the production efficiency can be improved. Further, by forming the coil and the near-field light generating element portion at the same time, the thickness of the near-field light head in the stacking direction can be reduced, and the near-field light head can be miniaturized. As a result, the position control of the slider provided with the near-field optical head can be stabilized, and a large amount of high-density information can be recorded and reproduced. Furthermore, since the positioning between the coil formed on the same plane and the near-field light generating element portion is facilitated, a near-field light head with high accuracy and improved yield can be provided.

  The information recording / reproducing apparatus according to the present invention can move in the direction parallel to the near-field optical head and the surface of the magnetic recording medium, and is parallel to the surface of the magnetic recording medium and orthogonal to each other. A beam that supports the near-field optical head on the distal end side in a state of being rotatable about an axis, a light source that makes the light beam incident on the optical waveguide portion, and a base end side of the beam, and An actuator for moving a beam in a direction parallel to the surface of the magnetic recording medium, a rotation driving unit for rotating the magnetic recording medium in the fixed direction, and a control for controlling the operation of the recording magnetic field generating unit and the light source And a section.

  According to this configuration, since the near-field optical head described above is provided, it is possible to provide a high-quality information recording / reproducing apparatus that has high writing reliability and can cope with high-density recording.

  According to the near-field light head according to (1) of the present invention, at the time of manufacturing the near-field light head, at least a part of the recording magnetic field generating portion and the near-field light generating element portion can be formed simultaneously. Therefore, the manufacturing process can be simplified and the production efficiency can be improved. Further, the near-field light head can be reduced in size by simultaneously forming at least a part of the recording magnetic field generating portion and the near-field light generating element portion. As a result, the position control of the slider provided with the near-field optical head can be stabilized, and a large amount of high-density information can be recorded and reproduced. Furthermore, since it becomes easy to position at least a part of the recording magnetic field generation unit formed on the same plane and the near-field light generation element unit, a near-field optical head with high accuracy and improved yield is provided. be able to.

It is a block diagram of the information recording / reproducing apparatus in embodiment of this invention. It is an expanded sectional view of the near-field light head in the embodiment. FIG. 3 is a cross-sectional view (partially transparent view) taken along line AA in FIG. 2. It is sectional drawing which follows the BB line of FIG. It is sectional drawing which follows the CC line of FIG. It is a figure (1) explaining the 1st manufacturing method of the near-field optical head in 1st Embodiment of this invention. It is a figure (2) explaining the 1st manufacturing method of the near-field optical head in 1st Embodiment of this invention. It is a figure (3) explaining the 1st manufacturing method of the near-field optical head in 1st Embodiment of this invention. It is a figure (4) explaining the 1st manufacturing method of the near-field optical head in 1st Embodiment of this invention. It is a figure (5) explaining the 1st manufacturing method of the near-field optical head in 1st Embodiment of this invention. It is a figure (6) explaining the 1st manufacturing method of the near-field optical head in 1st Embodiment of this invention. It is a figure (1) explaining the 2nd manufacturing method of the near-field optical head in 1st Embodiment of this invention. It is a figure (2) explaining the 2nd manufacturing method of the near-field optical head in 1st Embodiment of this invention. It is a figure (3) explaining the 2nd manufacturing method of the near-field optical head in 1st Embodiment of this invention. It is a figure (4) explaining the 2nd manufacturing method of the near-field optical head in 1st Embodiment of this invention. It is a figure (5) explaining the 2nd manufacturing method of the near-field optical head in 1st Embodiment of this invention. It is a figure which shows another aspect of the near-field optical head in 1st Embodiment of this invention. It is a figure which shows another aspect of the near-field optical head in 1st Embodiment of this invention. It is a figure which shows the near-field optical head in 2nd Embodiment of this invention, and is a figure corresponded in the cross section in alignment with the BB line of FIG. It is a figure which shows the near-field optical head in 2nd Embodiment of this invention, and is a figure corresponded in the cross section which follows the CC line | wire of FIG. It is a figure (1) explaining the manufacturing method of the near-field optical head in 2nd Embodiment of this invention. It is a figure (2) explaining the manufacturing method of the near-field optical head in 2nd Embodiment of this invention. It is a figure (3) explaining the manufacturing method of the near-field optical head in 2nd Embodiment of this invention. It is a figure (4) explaining the manufacturing method of the near-field optical head in 2nd Embodiment of this invention. It is a figure (5) explaining the manufacturing method of the near-field optical head in 2nd Embodiment of this invention. It is a figure which shows another aspect of the near-field optical head in 2nd Embodiment of this invention. It is a figure which shows another aspect of the near-field optical head in 2nd Embodiment of this invention. It is an expanded sectional view (equivalent to FIG. 4) which shows another aspect of the near-field optical head in embodiment of this invention. It is a figure (front view) which shows the example of a shape (1) of the near-field light generating element in embodiment of this invention. It is a figure (perspective view) which shows the example of a shape (2) of the near-field light generating element in embodiment of this invention. It is a figure (front view) which shows the example of a shape (3) of the near-field light generating element in embodiment of this invention. It is a figure which shows the example of arrangement | positioning (1) of the near-field light generation element in embodiment of this invention. It is a figure which shows the example of arrangement | positioning (2) of the near-field light generation element in embodiment of this invention. It is a figure which shows the example of arrangement | positioning (3) of the near-field light generation element in embodiment of this invention.

(First embodiment)
Next, a first embodiment of the present invention will be described with reference to the drawings. The information recording / reproducing apparatus 1 according to the present embodiment uses the hybrid magnetic recording method in which the near-field light and the recording magnetic field cooperate with respect to the disk D (magnetic recording medium) D having the perpendicular recording layer d2. This is an apparatus for recording and reproducing (see FIG. 2).

(Information recording / reproducing device)
FIG. 1 is a block diagram of an information recording / reproducing apparatus.
As shown in FIG. 1, the information recording / reproducing apparatus 1 of the present embodiment includes a near-field light head 2, a beam 3 that supports the near-field light head 2, and a laser beam (light beam) L ( 2), an actuator 5 that moves the beam 3, a spindle motor 6 that rotates the disk D in a fixed direction, and a controller 8 that comprehensively controls the above-described components. , And a housing 9 that houses each component.

  The housing 9 is formed of a metal material such as aluminum in a square shape in a plan view, and a recess 9a that accommodates each component is formed inside. Further, a lid (not shown) is detachably fixed to the housing 9 so as to close the opening of the recess 9a. A spindle motor 6 is attached to the approximate center of the recess 9a, and the disk D is fixed to the spindle motor 6. In the present embodiment, the case where three disks D are fixed to the spindle motor 6 is described as an example. However, the number of disks D is not limited to three.

  An actuator 5 is attached to one corner in the recess 9a. A carriage 11 is attached to the actuator 5 via a bearing 10. The carriage 11 is formed, for example, by cutting a metal material, and portions extending from the base end portion 11a fixed to the actuator 5 via the bearing 10 toward the front end are arranged on the upper surfaces of the three disks D, respectively. As shown in FIG. That is, it is formed so as to be E-shaped when the carriage 11 is viewed from the side. The proximal end side of the beam 3 is fixed to each distal end of the carriage 11 divided into three layers. Therefore, the actuator 5 supports the base end side of the beam 3 via the carriage 11, and scans the beam 3 in a horizontal direction parallel to the disk surface (the surface of the magnetic recording medium) D1 (see FIG. 2). It can be moved.

  As described above, the beam 3 is movable in the horizontal direction together with the carriage 11 by the actuator 5 and is rotated around two axes (X axis and Y axis) that are parallel to the disk surface D1 and orthogonal to each other. The near-field light head 2 is supported on the tip side in a free state. The beam 3 and the carriage 11 are retracted from the disk D by driving the actuator 5 when the rotation of the disk D is stopped.

(Near-field light head)
2 is an enlarged cross-sectional view of the near-field optical head, and FIG. 3 is a cross-sectional view (partially transparent view) taken along line AA in FIG.
As shown in FIGS. 2 and 3, the near-field light head 2 is a head that records and reproduces various information on the rotating disk D using near-field light generated from the laser light L. The near-field optical head 2 is disposed on the leading end side in the extending direction of the slider 20 disposed to face the disk D in a state of floating by a predetermined distance H from the disk surface D1, and generates a recording magnetic field to record information on the disk D. A recording magnetic field generating unit 21, a reproducing element 22 for reproducing information recorded on the disk D, and a near-field light generating element 26 for generating near-field light from the introduced laser light L. Further, the near-field optical head 2 of the present embodiment includes an optical waveguide portion 25 including a core 23 and a clad 24. In FIG. 2 and subsequent figures, the extending direction of the slider 20 is set to the X-axis direction, and the front end side in the extending direction is set to the + X direction. Further, the width direction of the slider 20 is set to the Y-axis direction, and the front side in FIG. Further, the vertical direction is set to the Z-axis direction, and the vertically upward side is set to the + Z direction.

  The slider 20 is formed in a rectangular parallelepiped shape from a light-transmitting material such as quartz glass or a ceramic such as AlTiC (AlTiC). The slider 20 has a facing surface 20a facing the disk D, and is supported so as to hang from the tip of the beam 3 via a gimbal portion 30 (see FIG. 2). The gimbal portion 30 is a component whose movement is restricted so as to be displaced only in the horizontal plane direction (around the X axis and around the Y axis). As a result, the slider 20 is rotatable about two axes (X axis and Y axis) that are parallel to the disk surface D1 and orthogonal to each other as described above.

  Further, on the facing surface 20a, there is formed a ridge portion 20b that generates a pressure for rising from the viscosity of the air flow generated by the rotating disk D. The ridges 20b are formed so as to extend along the longitudinal direction (X direction) of the slider 20, and are formed at two intervals in the short direction (Y direction) so as to be arranged in a rail shape. Yes. However, the ridge portion 20b is not limited to this case, and adjusts a positive pressure for separating the slider 20 from the disk surface D1 and a negative pressure for attracting the slider 20 to the disk surface D1, Any uneven shape may be used as long as the slider 20 is designed to float in an optimal state. The surface 20c of the ridge portion 20b is called ABS (AIR BEARING SURFACE).

The slider 20 receives a force that rises from the disk surface D1 by the two ridges 20b. On the other hand, the beam 3 is bent in the Z direction perpendicular to the disk surface D1, and absorbs the flying force of the slider 20. That is, the slider 20 receives a force pressed against the disk surface D1 side by the beam 3 when it floats. Therefore, the slider 20 floats in a state of being separated from the disk surface D1 by a predetermined distance H as described above due to the balance between the forces of the two. Moreover, since the slider 20 is rotated about the X axis and the Y axis by the gimbal portion 30, it always floats in a state where the posture is stable.
The air flow generated along with the rotation of the disk D flows from the inflow end side (the end portion in the −X direction of the beam 3) of the slider 20 and then flows along the surface 20c of the ridge portion 20b. It escapes from the outflow end side (the + X direction end of the beam 3).

  As shown in FIG. 3, the recording magnetic field generator 21 is an element that records information by applying a recording magnetic field to the disk D, and is an auxiliary magnetic pole fixed to the side surface (tip surface) on the outflow end side of the slider 20. 31, a main magnetic pole 33 that is connected to the auxiliary magnetic pole 31 via the magnetic circuit 32 and generates a recording magnetic field perpendicular to the disk D with the auxiliary magnetic pole 31, and the magnetic circuit 32 centering on the magnetic circuit 32. And a coil 34 wound around in a spiral.

  The auxiliary magnetic pole 31, the main magnetic pole 33, and the magnetic circuit 32 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 34 is arranged so that there is a gap between adjacent coil wires, between the magnetic circuit 32 and between the magnetic poles 31 and 33 so as not to be short-circuited. Has been. The clad 24 includes a first insulating layer 35 disposed between the core 23 and the slider 20, and a second insulating layer 36 disposed on the opposite side of the first insulating layer 35 via the core 23. It is configured (see FIG. 4).

  The coil 34 is supplied with a current modulated according to information from the control unit 8. That is, the magnetic circuit 32 and the coil 34 constitute an electromagnet as a whole. The main magnetic pole 33 and the auxiliary magnetic pole 31 are designed so that the end face (the end face in the −Z direction) facing the disk D is flush with the surface 20 c of the protruding portion 20 b of the slider 20. As shown in FIG. 3, the magnetic circuit 32 is formed so as to penetrate the first insulating layer 35 and the second insulating layer 36. Furthermore, both ends of the magnetic circuit 32 in the X direction are connected by the same conductive material as that of the magnetic poles 31 and 33. With this configuration, a recording magnetic field can be generated between the magnetic poles 31 and 33.

  4 is a cross-sectional view taken along line BB in FIG. 3, and FIG. 5 is a cross-sectional view taken along line CC in FIG. As shown in FIGS. 3 to 5, the optical waveguide portion 25 has an incident side (+ Z direction end) of the laser beam L facing upward of the slider 20, and an emission side (−Z direction end) is the disk D side. It is fixed in the state of facing. The optical waveguide portion 25 includes a core 23 for propagating the laser light L introduced from the incident side to the emission side facing the disk D, and a clad 24 that is in close contact with the core 23. It is formed in a shape.

  The core 23 is gradually drawn from the incident side (the end surface in the + Z direction) to the exit side (the end surface in the −Z direction) so that the laser beam L can be propagated while gradually condensing inside. . Specifically, the core 23 has a reflection surface 23a, a light beam condensing unit 23b, and a near-field light generating unit 23c from the incident side.

  The reflection surface 23a has a function of reflecting laser light L introduced from an optical waveguide 42 described later in a direction different from the introduction direction. The laser light L introduced from the optical waveguide 42 by the reflecting surface 23a propagates toward the emission side while repeating total reflection in the core 23.

  The light beam condensing unit 23b is a portion formed by drawing so that the cross-sectional area (cross-sectional area in the XY direction) orthogonal to the longitudinal direction (Z direction) from the incident side toward the emission side gradually decreases, and the laser introduced The light L is condensed and propagated toward the emission side. That is, the spot size of the laser beam L introduced into the light beam condensing unit 23b can be gradually reduced to a smaller size. The surface in contact with the first insulating layer 35 in the light beam condensing portion 23b is inclined so that the cross-sectional area decreases toward the Z direction emission side (−Z direction).

  The near-field light generating unit 23c is a portion that is further drawn from the end of the light beam condensing unit 23b toward the emission side. More specifically, in the vicinity of the exit side of the core 23, it is drawn by an inclined surface 23d inclined with respect to the optical axis (Z axis) of the laser light L propagating inside. The inclined surface 23d causes the core 23 to have a pointed shape on the emission side. The inclined surface 23 d is formed on a surface that contacts the first insulating layer 35.

  The near-field light generating unit 23 c is formed in a triangular shape so as to have three side surfaces, and one of the side surfaces (a flat surface facing the second insulating layer 36) faces the main magnetic pole 33. The near-field light generating element 26 is provided on the side surface thereof. Further, the end surface 23e exposed to the outside on the emission side of the near-field light generation unit 23c is designed to be flush with the surface 20c of the ridge portion 20b.

  The clad 24 composed of the first insulating layer 35 and the second insulating layer 36 is made of a material having a refractive index lower than that of the core 23, and the end surface on the incident side and the end surface 23 e on the output side of the core 23 are exposed to the outside. The core 23 is sealed inside by being in close contact with the side surface of the core 23 in an exposed state. Specifically, the clad 24 is formed so as to cover the first insulating layer 35 disposed between the core 23 and the slider 20 and the flat surface 23 f side of the core 23 between the core 23 and the main magnetic pole 33. And a second insulating layer 36. As described above, since the first insulating layer 35 and the second insulating layer 36 are in close contact with the respective side surfaces of the core 23, no gap is generated between the core 23 and the clad 24.

An example of a combination of materials used for the clad 24 and the core 23 is described. For example, a combination in which the core 23 is formed of quartz (SiO ₂ ) and the clad 24 is formed of fluorine-doped quartz is conceivable. In this case, when the wavelength of the laser beam L is 400 nm, the refractive index of the core 23 is 1.47 and the refractive index of the clad 24 is less than 1.47, which is a preferable combination.

A combination in which the core 23 is formed of quartz doped with germanium and the clad 24 is formed of quartz (SiO ₂ ) is also conceivable. In this case, when the wavelength of the laser beam L is 400 nm, the refractive index of the core 23 becomes larger than 1.47 and the refractive index of the cladding 24 becomes 1.47, which is also a preferable combination.

In particular, as the difference in refractive index between the core 23 and the clad 24 increases, the force for confining the laser light L in the core 23 increases. Therefore, when the core 23 has tantalum oxide (Ta ₂ O ₅ : wavelength is 550 nm) It is more preferable to increase the refractive index difference between the two by using 2.16) and using quartz or the like for the clad 24. In addition, when using the laser light L in the infrared region, it is also effective to form the core 23 with silicon (Si: refractive index is about 4) which is a material transparent to infrared light.

  Further, as described later, it is preferable to use a material having a high coefficient of thermal expansion as the material used for the clad 24 and the core 23. As such a material, a resin material as shown below is preferably used. For example, a combination in which the core 23 is formed with a thickness of 3 to 10 μm using PMMA (methyl methacrylate resin) and the clad 24 is formed with a thickness of several tens of μm using a fluorine-containing polymer is conceivable. Further, both the core 23 and the clad 24 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 composition of the resin material constituting the core 23 and the clad 24. 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.

  The near-field light generating element 26 is a metal film made of, for example, gold (Au), platinum (Pt), aluminum (Al), or the like, and is formed in the near-field light generating unit 23 c of the core 23. The near-field light generating element 26 generates near-field light from the laser light L propagating through the core 23, and localizes the near-field light between the end face 23e of the optical waveguide portion 25 and the disk D. is there.

  An optical waveguide 42 is fixed to the upper surface (+ Z direction end surface) of the slider 20. The optical waveguide 42 is a waveguide including a core 42a and a clad 42b, and the laser light L propagates through the core 42a. The front end (+ X direction end portion) of the optical waveguide 42 is connected to the incident side end portion of the core 23 of the optical waveguide portion 25, and emits the laser light L toward the reflecting surface 23a. The core 42a and the clad 42b are made of the same material as the core 23 and the clad 24 described above.

  Further, as shown in FIG. 1, the proximal end side of the optical waveguide 42 is pulled out along the beam 3 and the carriage 11 and then connected to the laser light source 43. The laser light source 43 is mounted on a control board 44 attached to the side surface of the base end portion 11a of the carriage 11 together with various electronic components such as an IC chip (not shown). In particular, the laser light source 43 emits the laser light L in a linearly polarized state. That is, the laser light source 43 and the optical waveguide 42 function as a light beam incident mechanism 4 that causes the laser light L to enter the near-field light head 2 in a linearly polarized state. The control board 44 on which the laser light source 43 is mounted is connected to the control unit 8 by a flexible flat cable (flexible board) 45. Thus, the control unit 8 performs an overall control by sending an electrical signal to each component. In particular, the timing at which the laser light source 43 emits the laser light L is controlled by the control unit 8.

  The reproducing element 22 is a magnetoresistive film whose electric resistance is converted according to the magnitude of the magnetic field leaking from the perpendicular recording layer d2 of the disk D, and is formed on the side surface (+ X direction side surface) of the second insulating layer 36. The third insulating layer 37 is formed on the side surface (+ X direction side surface). A bias current is supplied to the reproducing element 22 from the control unit 8 via a lead film (not shown). Thus, the control unit 8 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. A protective layer 38 is formed so as to cover the reproducing element 22 and the third insulating layer 37.

  As shown in FIG. 2, the disk D of this embodiment has at least two of a perpendicular recording layer d2 having an easy axis of magnetization in a direction perpendicular to the disk surface D1, and a soft magnetic layer d3 made of a high magnetic permeability material. A vertical two-layer film disc D composed of layers is used. As such a disk D, for example, a disk in which a soft magnetic layer d3, an intermediate layer d4, a perpendicular recording layer d2, a protective layer d5, and a lubricating layer d6 are sequentially formed on a substrate d1 is used. .

  For example, an aluminum substrate or a glass substrate is used as the substrate d1. The soft magnetic layer d3 is a high magnetic permeability layer. The intermediate layer d4 is a crystal control layer of the perpendicular recording layer d2. The perpendicular recording layer d2 is a perpendicular anisotropic magnetic layer, and for example, a CoCrPt alloy is used. The protective layer d5 is for protecting the perpendicular recording layer d2, and for example, a DLC (Diamond Like Carbon) film is used. For the lubrication layer d6, for example, a fluorine-based liquid lubricant is used.

(Near-field optical head manufacturing method)
Next, a manufacturing method of the near-field optical head 2 configured as described above will be described. In the drawings showing the subsequent manufacturing process of the near-field optical head 2, a cross-sectional view taken along line DD in FIG. 3 is shown on the left side of each figure, and a cross-sectional view taken along line EE in FIG. Indicates.

(First manufacturing method)
As shown in FIG. 6, first, the lower yoke 32 a of the magnetic circuit 32 is patterned together with the auxiliary magnetic pole 31 of the magnetic material on the substrate (for example, AlTiC (AlTiC) or the like) to be the slider 20. The auxiliary magnetic pole 31 and the lower yoke 32a are connected by a magnetic material. Subsequently, a first insulating layer 35 that serves as an insulation between each magnetic pole and the coil 34 is formed together with the role of the clad 24 of the optical waveguide portion 25.

  Subsequently, as shown in FIG. 7, a resist material 47 is applied on the first insulating layer 35. Subsequently, a concave resist pattern 48 for patterning the core 23 and the coil 34 of the optical waveguide portion 25 is formed. For resist patterning, for example, if a method such as nanoimprint pressing with a mold 49 shown in FIG. 7 is used, processing can be performed efficiently and at low cost.

Subsequently, as shown in FIG. 8, the above-described resist pattern 48 is transferred onto the first insulating layer 35 by a dry etching method, and the groove 50 for forming the core 23 and the groove for forming the coil 34 of the optical waveguide portion 25. The resist material 47 and the first insulating layer 35 are etched until 51 is processed. By doing so, it is possible to process the grooves 50 and 51 on the first insulating layer 35, which are places where the core 23, the near-field light generating element 26, and the coil 34 of the optical waveguide portion 25 are formed. The grooves 50 and 51 may be processed by a pressing method in which the first insulating layer 35 is directly pressed with a mold without coating and patterning a resist.

  Subsequently, an optical waveguide member 52 is formed in the groove 50 for the core 23. As a forming method, there is a method in which a predetermined amount of resin or the like configured as the optical waveguide member 52 is directly injected into the groove 50. Further, a method of forming the optical waveguide member 52 in the groove 50 by using a spin coat method after protecting the groove 51 for the coil 34 with the protective material 53 may be used. By doing so, the core 23 can be formed.

  Subsequently, as shown in FIG. 9, a material (for example, Au) 54 of the near-field light generating element 26 and the coil 34 is formed so as to have a predetermined film thickness. Subsequently, the film other than the portion where the near-field light generating element 26 and the coil 34 are formed is removed by photolithography and etching. Subsequently, the film other than the film in the groove 51 and the portion where the near-field light generating element 26 is disposed in the groove 50 are removed by means such as polishing. By doing so, the near-field light generating element 26 and the coil 34 can be simultaneously formed on the same plane.

  Subsequently, as shown in FIG. 10, each magnetic pole and the coil 34, together with the role of the clad 24 of the optical waveguide portion 25 so as to cover the first insulating layer 35, the near-field light generating element 26, the coil 34, and the core 23. A second insulating layer 36 that functions as an insulating layer is formed. Subsequently, in order to form the magnetic circuit 32, a through hole 55 for connecting the auxiliary magnetic pole 31 and the main magnetic pole 33 is formed. Specifically, the through-hole 55 is formed so as to pass through a position corresponding to the central portion of the coil 34, penetrate the first insulating layer 35 and the second insulating layer 36, and expose the lower yoke 32a.

  Subsequently, as shown in FIG. 11, the main magnetic pole 33 made of a magnetic material and the upper yoke 32b of the magnetic circuit 32 are formed on the second insulating layer 36, and the through yoke 32c is formed (the through hole 55 is made of a magnetic material). Fill). The main magnetic pole 33 and the upper yoke 32b are connected by a magnetic material. Further, the positions of the main magnetic pole 33 and the auxiliary magnetic pole 31 may be exchanged. With this configuration, the upper yoke 32b and the lower yoke 32a are connected by a magnetic material via the through yoke 32c, and the auxiliary magnetic pole 31 and the main magnetic pole 33 are connected by a magnetic material. It will be. Thereby, the magnetic circuit 32 is formed, and the recording magnetic field generating unit 21 is formed by the magnetic circuit 32 and the coil 34.

Further, a third insulating layer 37 is formed so as to cover the main magnetic pole 33 and the second insulating layer 36, and the reproducing element 22 is formed on the third insulating layer 37. The reproducing element 22 is formed at a position facing the auxiliary magnetic pole 31 and the main magnetic pole 33. Further, the position of the reproducing element 22 may be set relatively freely, and may be disposed on the substrate before the auxiliary magnetic pole 31 is formed, for example. Subsequently, a protective layer 38 is formed so as to cover the reproducing element 22 and the third insulating layer 37.
By doing so, the near-field optical head 2 can be manufactured.

(Second manufacturing method)
Next, a manufacturing method different from the above-described method for manufacturing the near-field optical head 2 configured as described above will be described.
First, similarly to FIG. 6 described above, first, the lower yoke 32a of the magnetic circuit 32 is patterned together with the auxiliary magnetic pole 31 made of a magnetic material on a substrate (for example, AlTiC (AlTiC) or the like) to be the slider 20. The auxiliary magnetic pole 31 and the lower yoke 32a are connected by a magnetic material. Subsequently, a first insulating layer 35 that serves as an insulation between each magnetic pole and the coil 34 is formed together with the role of the clad 24 of the optical waveguide portion 25.

  Subsequently, as in FIG. 7 described above, a resist material 47 is applied on the first insulating layer 35. Subsequently, a concave resist pattern 48 for patterning the core 23 and the coil 34 of the optical waveguide portion 25 is formed. For resist patterning, for example, if a method such as nanoimprint pressing with a mold 49 shown in FIG. 7 is used, processing can be performed efficiently and at low cost. Subsequently, until the above-described resist pattern 48 is transferred onto the first insulating layer 35 by a dry etching method, and the groove 50 for forming the core 23 and the groove 51 for forming the coil 34 of the optical waveguide portion 25 are processed. The resist material 47 and the first insulating layer 35 are etched. By doing so, it is possible to process the grooves 50 and 51 on the first insulating layer 35, which are places where the core 23, the near-field light generating element 26, and the coil 34 of the optical waveguide portion 25 are formed. The grooves 50 and 51 may be processed by a pressing method in which the first insulating layer 35 is directly pressed with a mold without coating and patterning a resist.

  Subsequently, as shown in FIG. 12, an optical waveguide member 52 is formed so as to cover the first insulating layer 35.

  Subsequently, as shown in FIG. 13, polishing or the like is used for the optical waveguide member 52, and the polishing is finished when the optical waveguide member 52 in each of the grooves 50 and 51 is not scraped. By doing so, the core 23 can be formed. At this time, the optical waveguide member 52 has also slightly penetrated into the groove 51 where the coil 34 is formed.

  Subsequently, as shown in FIG. 14, the near-field light generating element 26 and the material 54 (for example, Au) of the coil 34 are formed to have a predetermined film thickness. Subsequently, the film other than the portion where the near-field light generating element 26 and the coil 34 are formed is removed by photolithography and etching. Subsequently, the film other than the film in the groove 51 and the portion where the near-field light generating element 26 is disposed in the groove 50 are removed by means such as polishing. By doing so, the near-field light generating element 26 and the coil 34 can be simultaneously formed on the same plane.

  Subsequently, as shown in FIG. 15, the magnetic poles and the coils 34 are arranged together with the roles of the clad 24 of the optical waveguide portion 25 so as to cover the first insulating layer 35, the near-field light generating element 26, the coil 34, and the core 23. A second insulating layer 36 that functions as an insulating layer is formed. Subsequently, in order to form the magnetic circuit 32, a through hole 55 for connecting the auxiliary magnetic pole 31 and the main magnetic pole 33 is formed. Specifically, the through-hole 55 is formed so as to pass through a position corresponding to the central portion of the coil 34, penetrate the first insulating layer 35 and the second insulating layer 36, and expose the lower yoke 32a.

  Subsequently, as shown in FIG. 16, the main magnetic pole 33 made of a magnetic material and the upper yoke 32b of the magnetic circuit 32 are formed on the second insulating layer 36, and the through yoke 32c is formed (the through hole 55 is made of a magnetic material). Fill). The main magnetic pole 33 and the upper yoke 32b are connected by a magnetic material. Further, the positions of the main magnetic pole 33 and the auxiliary magnetic pole 31 may be exchanged. With this configuration, the upper yoke 32b and the lower yoke 32a are connected by a magnetic material via the through yoke 32c, and the auxiliary magnetic pole 31 and the main magnetic pole 33 are connected by a magnetic material. It will be. Thereby, the magnetic circuit 32 is formed, and the recording magnetic field generating unit 21 is formed by the magnetic circuit 32 and the coil 34.

Further, a third insulating layer 37 is formed so as to cover the main magnetic pole 33 and the second insulating layer 36, and the reproducing element 22 is formed on the third insulating layer 37. The reproducing element 22 is formed at a position facing the auxiliary magnetic pole 31 and the main magnetic pole 33. Further, the position of the reproducing element 22 may be set relatively freely, and may be disposed on the substrate before the auxiliary magnetic pole 31 is formed, for example. Subsequently, a protective layer 38 is formed so as to cover the reproducing element 22 and the third insulating layer 37.
By doing so, the near-field optical head 2 can be manufactured.

  In addition, you may comprise as FIG. 17, FIG. 18 as another structure of the near-field optical head 2 mentioned above. In FIGS. 17 and 18, similarly to the drawings showing the manufacturing process of the near-field optical head 2 described above, the left side of each drawing shows a cross-sectional view of the position corresponding to the line DD in FIG. Sectional drawing of the position equivalent to the EE line | wire of 3 is shown.

  In the near-field light head of FIG. 17, the near-field light generating element 26, the main magnetic pole 33, and the coil 34 are formed on the same plane. With such a configuration, the number of stacked layers is smaller than that of the above-described near-field optical head 2, and thus a more compact near-field optical head can be provided.

  In order to manufacture the near-field optical head as shown in FIG. 17, the grooves 50 and 51 for the core 23 and the coil 34 are formed by drawing a pattern for forming the main magnetic pole 33 on the pressing mold in FIG. At the same time, the groove 57 for the main magnetic pole 33 can be formed simultaneously. Further, regarding the method of forming the main magnetic pole 33 in the groove 57, for example, in FIG. 9, the grooves 50 and 51 other than the groove 57 for the main magnetic pole 33 are protected, a magnetic material is deposited, and polishing is performed. Thus, the magnetic material other than the groove 57 for the main magnetic pole 33 can be removed.

  Further, when the through hole 55 is opened in FIG. 10, by simultaneously opening the through hole 58, the upper yoke 32b and the main yoke 32b are connected to the main yoke 32b as shown in FIG. 17 simultaneously with the step of connecting the lower yoke 32a and the upper yoke 32b in FIG. The magnetic pole 33 can be connected. In this way, the near-field optical head shown in FIG. 17 can be manufactured.

  In FIG. 18, the near-field light generating element 26, the auxiliary magnetic pole 31, the main magnetic pole 33, and the coil 34 are formed on the same plane. With this configuration, the number of stacked layers is further reduced as compared with the near-field optical head 2 described above, and thus a more compact near-field optical head can be provided.

  In order to manufacture the near-field optical head as shown in FIG. 18, not the auxiliary magnetic pole 31 but the lower yoke 59 is formed in FIG. Further, in FIG. 7, a pattern for forming the main magnetic pole 33 and the auxiliary magnetic pole 31 is drawn in a pressing shape, so that the grooves for the main magnetic pole 33 and the auxiliary magnetic pole 31 are formed together with the grooves 50 and 51 for the core 23 and the coil 34. 60, 61 can be formed simultaneously. Further, regarding the method of forming the main magnetic pole 33 and the auxiliary magnetic pole 31 in the grooves 60 and 61, for example, in FIG. 9, the grooves other than the grooves 60 and 61 for the main magnetic pole 33 and the auxiliary magnetic pole 31 are protected and magnetic After depositing the material, the magnetic material other than the grooves 60 and 61 for the main magnetic pole 33 and the auxiliary magnetic pole 31 can be removed by polishing or the like.

  Further, by opening the through hole 62 when the through hole 55 is opened in FIG. 10, the upper yoke 32b and the main magnetic pole as shown in FIG. 18 are formed simultaneously with the step of connecting the lower yoke 32a and the upper yoke 32b in FIG. 33 can be connected. In this manner, the near-field optical head shown in FIG. 18 can be manufactured.

  17 and 18, the positions of the main magnetic pole 33 and the auxiliary magnetic pole 31 may be changed, and the main magnetic pole 33 and the auxiliary magnetic pole 31 are disposed on the left side of the near-field light generating element 26. May be.

  According to this embodiment, when manufacturing the near-field light head 2, the coil 34 of the recording magnetic field generating unit 21 and the near-field light generating element 26 can be formed simultaneously. Therefore, the manufacturing process can be simplified and the production efficiency can be improved. Further, by forming the coil 34 of the recording magnetic field generating unit 21 and the near-field light generating element 26 at the same time, the thickness of the near-field light head 2 in the stacking direction can be reduced, and the near-field light head 2 can be reduced in size. Can be As a result, the position control of the slider 20 provided with the near-field optical head 2 can be stabilized, and a large amount of high-density information can be recorded and reproduced. Further, since the positioning of the coil 34 and the near-field light generating element 26 of the recording magnetic field generating unit 21 formed on the same plane is facilitated, the near-field light head 2 with high accuracy and improved yield is provided. can do.

  In addition, since the information recording / reproducing apparatus 1 includes the near-field optical head 2 described above, it is possible to provide a high-quality information recording / reproducing apparatus 1 that has high writing reliability and can cope with high-density recording. Can do.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. The information recording / reproducing apparatus of the present embodiment is different from the information recording / reproducing apparatus of the first embodiment only in the configuration of the near-field optical head, and the other configurations are substantially the same. Detailed description will be omitted. Further, in the drawings showing the subsequent manufacturing process of the near-field optical head 102, a sectional view taken along the line DD of FIG. 3 is shown on the left side of each figure, and a sectional view taken along the line EE of FIG. Indicates.

  19 is a cross-sectional view taken along line BB in FIG. 3 in the present embodiment, and FIG. 20 is a cross-sectional view taken along line CC in FIG. As shown in FIGS. 19 and 20, in the near-field optical head 102, the auxiliary magnetic pole 131 and the main magnetic pole 133 are at positions opposite to those in the first embodiment, that is, the main magnetic pole 133 is closer to the slider 20 than the core 123 ( The auxiliary magnetic pole 131 is arranged on the opposite side of the slider 20 via the core 123. The near-field light generating element 126 is formed at a position facing the main magnetic pole 133, and the light flux condensing part 123 b and the inclined surface 123 d of the core 123 are formed on the side facing the second insulating layer 136. .

(Near-field optical head manufacturing method)
Next, a method for manufacturing the near-field optical head 102 configured as described above will be described.

  21, first, the lower yoke 132a of the magnetic circuit 132 is patterned together with the main magnetic pole 133 made of a magnetic material on a substrate (for example, AlTiC (altic)) to be the slider 20. The main magnetic pole 133 and the lower yoke are patterned. The first insulating layer 135 serves as an insulation between the magnetic poles 131 and 133 and the coil 134 as well as the clad 124 of the optical waveguide portion 125. Subsequently, a material 154 (for example, Au) of the near-field light generating element 126 and the coil 134 is formed to have a predetermined film thickness, and then the near-field light generating element 126 and the coil 134 are formed. The film other than the portion where the film is formed is removed by, for example, photolithography and etching, and the optical waveguide member 152 is formed on the first insulating layer 135. To film.

  Subsequently, as shown in FIG. 22, a resist material 147 is applied on the optical waveguide member 152 to form a convex resist pattern 148 for patterning the core 123 and the coil 134 of the optical waveguide portion 125. For resist patterning, for example, if a method such as nanoimprint pressing with a mold 149 shown in FIG. 22 is used, processing can be performed efficiently and at low cost.

  Subsequently, as shown in FIG. 23, the resist pattern is transferred to the optical waveguide member 152 by dry etching, the core 123 of the optical waveguide portion 125 and the protruding portion 165 for coil processing are processed, and the near-field light generating element 126 is processed. The resist material 147 and the optical waveguide member 152 are etched until the material (film) 154 to be the coil 134 is exposed. By doing in this way, the core 123 of the optical waveguide part 125 and the protruding part 165 for coil processing can be simultaneously formed on the same plane.

  For processing the core 123 of the optical waveguide portion 125 and the protruding portion 165 for coil processing, a pressing method in which the optical waveguide member 152 is directly pressed with a mold without coating and patterning a resist can also be used. The convex resist pattern 148 for patterning the core 123 and the coil 134 of the optical waveguide part 125 can also be dry etched.

  Next, as shown in FIG. 24, the material 154 to be the near-field light generating element 126 and the coil 134 is formed in such a way that the core 123 of the optical waveguide portion 125 and the protruding portion 165 for coil processing are not damaged. Etching is performed so that only the film just below 123 and the coil machining ledge 165 remains. As an etching means, for example, there is a wet etching method. By doing so, the near-field light generating element 126 and the coil 134 can be simultaneously formed on the same plane.

  Subsequently, as shown in FIG. 25, the magnetic poles 131 and 133 together with the role of the clad 124 of the optical waveguide portion 125 so as to cover the first insulating layer 135, the near-field light generating element 126, the coil 134, and the core 123. A second insulating layer 136 that serves as an insulation between the coil 134 and the coil 134 is formed. Subsequently, in order to form the magnetic circuit 132, a through-hole 155 for connecting the auxiliary magnetic pole 131 and the main magnetic pole 133 is formed. Specifically, the through-hole 155 is formed so as to pass through a position corresponding to the central portion of the coil 134, penetrate the first insulating layer 135 and the second insulating layer 136, and expose the lower yoke 132a.

  Subsequently, the auxiliary magnetic pole 131 made of a magnetic material and the upper yoke 132b of the magnetic circuit 132 are formed on the second insulating layer 136, and the through yoke 132c is formed (the through hole 155 is filled with the magnetic material). The auxiliary magnetic pole 131 and the upper yoke 132b are connected by a magnetic material. Further, the positions of the main magnetic pole 133 and the auxiliary magnetic pole 131 may be interchanged. With this configuration, the upper yoke 132b and the lower yoke 132a are connected by the magnetic material via the through yoke 132c, and the auxiliary magnetic pole 131 and the main magnetic pole 133 are connected by the magnetic material. It will be. As a result, a magnetic circuit 132 is formed, and a recording magnetic field generation unit 121 is formed by the magnetic circuit 132 and the coil 134.

Then, a third insulating layer 137 is formed so as to cover the auxiliary magnetic pole 131 and the second insulating layer 136, and the reproducing element 122 is formed on the third insulating layer 137. The reproducing element 122 is formed at a position facing the auxiliary magnetic pole 131 and the main magnetic pole 133. Further, the position of the reproducing element 122 is set relatively freely, and may be disposed on the substrate before the main magnetic pole 133 is formed, for example. Subsequently, a protective layer 138 is formed so as to cover the reproducing element 122 and the third insulating layer 137.
By doing so, the near-field optical head 102 can be manufactured.

  In addition, you may comprise as FIG. 26, FIG. 27 as another structure of the near-field optical head 102 mentioned above. In FIGS. 26 and 27, similarly to the drawings showing the manufacturing process of the near-field optical head 102 described above, the left side of each figure shows a cross-sectional view of the position corresponding to the line DD in FIG. Sectional drawing of the position equivalent to the EE line | wire of 3 is shown.

  In the near-field light head of FIG. 26, the near-field light generating element 126, the main magnetic pole 133, and the coil 134 are formed on the same plane. With such a configuration, the number of stacked layers is smaller than that of the above-described near-field optical head 102, and thus a more compact near-field optical head can be provided.

  In order to manufacture the near-field optical head as shown in FIG. 26, the lower yoke 159 is formed instead of the main magnetic pole 133 in FIG. In addition, the main magnetic pole 133 made of a magnetic material is formed at a predetermined location (near the near-field light generating element 126) on the first insulating layer 135 where the films other than those necessary for forming the near-field light generating element 126 and the coil 134 are removed. For example, a step of patterning is added by means such as lift-off. By doing so, the near-field optical head of FIG. 26 can be manufactured.

  In FIG. 27, the near-field light generating element 126, the auxiliary magnetic pole 131, the main magnetic pole 133, and the coil 134 are formed on the same plane. With this configuration, since the number of stacked layers is further reduced as compared with the above-described near-field optical head 102, a more compact near-field optical head can be provided.

In order to manufacture the near-field optical head as shown in FIG. 27, the lower yoke 159 is formed instead of the main magnetic pole 133 in FIG. In addition, the main magnetic pole 133 made of a magnetic material is formed at a predetermined location (near the near-field light generating element 126) on the first insulating layer 135 where the films other than those necessary for forming the near-field light generating element 126 and the coil 134 are removed. In addition, a process of patterning the auxiliary magnetic pole 131 by means such as lift-off is added.
25, when the through hole 155 is opened, by opening the through hole 162, the upper yoke 132b and the auxiliary magnetic pole 131 are simultaneously connected as shown in FIG. 27 simultaneously with the step of connecting the lower yoke 132a and the upper yoke 132b. Can be connected. By doing so, the near-field optical head of FIG. 27 can be manufactured.

  Also in this embodiment, substantially the same operational effects as those of the first embodiment can be obtained.

(Information recording and playback method)
Next, a case where various kinds of information is recorded / reproduced on / from the disk D by the information recording / reproducing apparatus 1 configured as above will be described below.
First, as shown in FIG. 1, the spindle motor 6 is driven to rotate the disk D in a certain direction. Next, the actuator 5 is actuated to scan the beam 3 in the XY directions via the carriage 11. As a result, the near-field light head 2 can be positioned at a desired position on the disk D. At this time, the near-field optical head 2 receives a force that rises by the two ridges 20b formed on the opposing surface 20a of the slider 20, and is pressed against the disk D by a predetermined force by the beam 3 or the like. The near-field optical head 2 floats to a position separated by a predetermined distance H from the disk D as shown in FIG.

  Further, even if the near-field optical head 2 receives wind pressure generated due to the undulation of the disk D, the beam 3 absorbs the displacement in the Z direction and is displaced around the XY axis by the gimbal portion 30. Can be absorbed, so wind pressure caused by swell can be absorbed. Therefore, the near-field light head 2 can be floated in a stable state. Here, since the near-field optical head 2 of this embodiment can be reduced in size, it can be floated in a more stable state.

  When recording information on the disk D, the control unit 8 operates the laser light source 43 to emit linearly polarized laser light L, and supplies a current modulated according to the information to the coil 34 to record the magnetic field generating unit 21. Is activated.

  First, the laser light L is incident on the optical waveguide 42 from the laser light source 43 to guide the laser light L to the slider 20 side. The laser light L emitted from the laser light source 43 travels toward the tip (outflow end) side in the core 42 a of the optical waveguide 42 and propagates into the core 23 of the optical waveguide portion 25. The laser light L propagated in the core 23 propagates in the light beam condensing part 23b. The laser beam L propagating through the light beam condensing unit 23b propagates while repeating total reflection between the core 23 and the clad 24 toward the emission side (−Z direction) located on the disk D side. In particular, since the clad 24 is in close contact with the side surface of the core 23, light does not leak outside the core 23. Therefore, the introduced laser beam L can be propagated to the emission side while being stopped without being wasted and incident on the near-field light generating element 26.

  At this time, the core 23 is drawn so that a cross-sectional area perpendicular to the longitudinal direction (Z direction) from the incident side to the emission side gradually decreases. Therefore, the laser beam L is gradually narrowed as it propagates in the light beam condensing part 23b, and the spot size is reduced.

  Subsequently, the laser beam L having a reduced spot size is incident on the near-field light generator 23c. Then, the laser light L enters the near-field light generating element 26. As a result, surface plasmons are excited in the near-field light generating element 26. The excited surface plasmon propagates from the interface between the near-field light generating element 26 and the core 23 (near-field light generating unit 23c) toward the emission side of the core 23 while being enhanced by the resonance effect. And when it reaches the emission side, it becomes near-field light with strong light intensity and leaks to the outside. That is, near-field light can be localized between the end face 23e of the core 23 and the disk D. Then, the disk D is locally heated by the near-field light, and the coercive force is temporarily reduced.

  On the other hand, when a current is supplied to the coil 34 by the control unit 8, the current magnetic field generates a magnetic field in the magnetic circuit 32 according to the principle of the electromagnet, so that the disk D is interposed between the main magnetic pole 33 and the auxiliary magnetic pole 31. A perpendicular recording magnetic field can be generated. Then, the magnetic flux generated from the main magnetic pole 33 side passes straight through the perpendicular recording layer d2 of the disk D and reaches the soft magnetic layer d3. As a result, recording can be performed in a state where the magnetization of the perpendicular recording layer d2 is directed perpendicular to the disk surface D1. The magnetic flux reaching the soft magnetic layer d3 returns to the auxiliary magnetic pole 31 via the soft magnetic layer d3. At this time, when returning to the auxiliary magnetic pole 31, the direction of magnetization is not affected. This is because the area of the auxiliary magnetic pole 31 facing the disk surface D1 is larger than that of the main magnetic pole 33, so that the magnetic flux density is large and a force sufficient to reverse the magnetization does not occur. That is, recording can be performed only on the main magnetic pole 33 side.

  As a result, information can be recorded by a hybrid magnetic recording method in which near-field light and recording magnetic fields generated by both magnetic poles 31 and 33 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 stable recording can be performed. Therefore, writing reliability can be improved.

  Further, when reproducing information recorded on the disk D, the reproducing element 22 receives a magnetic field leaking from the perpendicular recording layer d2 of the disk D when the coercive force of the disk D is temporarily reduced. Thus, the electrical resistance changes according to the size. Therefore, the voltage of the reproducing element 22 changes. Thereby, the control unit 8 can detect a change in the magnetic field leaking from the disk D as a change in voltage. The control unit 8 can reproduce information recorded on the disk D by reproducing a signal from the change in voltage.

  When recording / reproduction is not performed, the operation of the laser light source 43 is stopped.

It should be noted that 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-described embodiment, the air floating type information recording / reproducing apparatus in which the near-field optical head is levitated has been described as an example. However, the present invention is not limited to this case. The reproducing head may be in contact. That is, the near-field optical head of the present invention may be a contact slider type near-field optical head. Even in this case, substantially the same operational effects can be achieved.

  Moreover, in the said embodiment, although the case where the core 23 of the optical-waveguide part 25 was gradually drawn from one end side toward the other end side was mentioned as an example, it is not restricted to this case, as shown in FIG. It may be formed straight. In addition, what is necessary is just to change the shape of the concave resist pattern for patterning demonstrated in the said embodiment, when making the shape of the core 23 into a shape different from the said embodiment.

  In the above embodiment, the case where the near-field optical head 2 of the present invention is employed in a perpendicular magnetic recording system that applies a recording magnetic field perpendicular to the disk D has been described. You may employ | adopt for the in-plane recording system which gives a horizontal recording magnetic field.

  Further, the shape of the near-field light generating element 26 (126) in the above embodiment is not particularly limited. For example, as shown in FIG. 29, the near-field composed of a disc portion 26a and a rod-like portion 26b. The light generating element 26A may be used. The near-field light generating element 26A is configured such that plasmons are generated when the disk portion 26a is irradiated with laser light (light flux) L, and near-field light is generated from the plasmons in the rod-like portion 26b. With this configuration, near-field light can be generated with high energy efficiency. 29 is a front view seen from the X direction of FIG. Moreover, as shown in FIG. 30, the thickness of the disc part 26a may be made thicker than the rod-like part 26b. Moreover, as shown in FIG. 31, you may comprise the disc part 26a with the rectangular-shaped square plate part 26c. In the above embodiment, the near-field light generating element 26 (126) is formed on the flat surface 23f side of the core 23. However, as shown in FIG. 32, the near-field light generating element 26 is in contact with the end surface 23e of the core 23. 26B may be formed. At this time, the near-field light generating element 26B has a triangular shape when viewed from the Z direction, but the apex located on the −X side of the triangle is preferably disposed at a position corresponding to the center of the light spot. . Furthermore, as shown in FIG. 33, the near-field light generating element 26 </ b> C may be formed on the inclined surface 23 d of the core 23. FIG. 34 shows a modification of the shape of the core 23 of FIG. 33, but the near-field light generating element 26C may be formed on the inclined surface 23d and the distal end portion 26g. 32 and 33 are views seen from the Y direction, and FIG. 34 is a view seen from the X direction. Also, each of the near-field light generating elements 26A to 26C shown in FIGS. 29 to 34 can be formed using the method such as photolithography described in the above embodiment.

  The near-field optical head of the present invention can be suitably used for an information recording / reproducing apparatus such as a hard disk in computer equipment.

DESCRIPTION OF SYMBOLS 1 ... Information recording / reproducing apparatus 2 ... Near-field optical head 3 ... Beam 5 ... Actuator 6 ... Spindle motor (rotation drive part)
8 ... Control unit 20 ... Slider (substrate)
DESCRIPTION OF SYMBOLS 21 ... Recording magnetic field generation part 23 ... Core 25 ... Optical waveguide part 26 ... Near field light generation element (near field light generation element part)
26a ... disk part (plasmon generating part)
26b ... Rod-shaped part (near-field light generating part)
31 ... Auxiliary magnetic pole 32 ... Magnetic circuit 32a ... Lower yoke (one end of magnetic circuit)
32b ... Upper yoke (the other end of the magnetic circuit)
33 ... Main magnetic pole 34 ... Coil 35 ... First insulating layer 36 ... Second insulating layer 43 ... Laser light source (light source)
50 ... groove (recess)
51 ... groove (recess)
52 ... Optical waveguide member 54 ... Near-field light generating element and coil material (conductive material)
55 ... through hole D ... disk (magnetic recording medium)
D1 ... disk surface (front surface)

Claims (5)

A recording magnetic field generator for generating a recording magnetic field disposed on the leading end side in the extending direction of a slider disposed opposite to the surface of the magnetic recording medium rotating in a certain direction;
An optical waveguide for propagating a light beam toward the magnetic recording medium;
A near-field light generating element for generating near-field light from the luminous flux;
An insulating layer constituting the optical waveguide portion;
With
The recording magnetic field generator is
An auxiliary pole;
A main magnetic pole connected to the auxiliary magnetic pole via a magnetic circuit and generating the recording magnetic field with respect to the magnetic recording medium between the auxiliary magnetic pole;
A coil wound around the magnetic circuit around the magnetic circuit;
With
The auxiliary magnetic pole, the near-field light generating element part, and the main magnetic pole are laminated in this order on the front end surface in the extending direction of the slider,
The width of the core of the optical waveguide portion gradually decreases toward the magnetic recording medium side,
The near-field light head, wherein the coil and the near-field light generating element portion are formed on the same plane . The near-field light generating element part is
A plasmon generator for generating plasmons from the luminous flux;
A near-field light generator for generating the near-field light from the plasmon;
The near-field optical head according to claim 1, comprising: A recording magnetic field generator for generating a recording magnetic field disposed on the leading end side in the extending direction of a slider disposed opposite to the surface of the magnetic recording medium rotating in a certain direction;
An optical waveguide for propagating a light beam toward the magnetic recording medium;
A near-field light generating element for generating near-field light from the luminous flux;
A near-field optical head comprising:
Forming an auxiliary magnetic pole of the recording magnetic field generating unit made of a magnetic material and one end of a magnetic circuit on a substrate serving as the slider;
Forming a first insulating layer on the substrate;
Forming a recess at a location on the first insulating layer where the core of the optical waveguide portion and the coil of the recording magnetic field generating portion are provided;
Disposing an optical waveguide member in a region of the recess that is configured as a core of the optical waveguide portion;
Forming the near-field light generating element portion by forming a conductive material on the magnetic recording medium side end portion of the concave portion configured as the optical waveguide portion, and simultaneously forming the coil in the concave portion Forming a coil by forming a conductive material on the coil;
Forming a second insulating layer on the first insulating layer;
Forming a through hole communicating with one end of the magnetic circuit in the first insulating layer and the second insulating layer;
The magnetic material is disposed in the through hole, the other end of the magnetic circuit made of the magnetic material is formed at a position corresponding to the through hole on the second insulating layer, and the second insulating layer is formed on the second insulating layer. Forming a main magnetic pole of the recording magnetic field generating portion at a position facing the auxiliary magnetic pole in
A method for manufacturing a near-field optical head, comprising: A recording magnetic field generator for generating a recording magnetic field disposed on the leading end side in the extending direction of a slider disposed opposite to the surface of the magnetic recording medium rotating in a certain direction;
An optical waveguide for propagating a light beam toward the magnetic recording medium;
A near-field light generating element for generating near-field light from the luminous flux;
A near-field optical head comprising:
Forming a main magnetic pole of the recording magnetic field generating unit made of a magnetic material and one end of a magnetic circuit on a substrate to be the slider;
Forming a first insulating layer on the substrate;
Forming a conductive material in a position corresponding to the magnetic recording medium side end of the optical waveguide portion, and simultaneously forming a conductive material in a region configured as a coil of the recording magnetic field generating portion;
Patterning the shape of the core of the optical waveguide portion and the coil at a location where the core of the optical waveguide portion and the coil are provided on the first insulating layer;
Etching the conductive material using the patterning to form the near-field light generating element portion and the coil;
Forming a second insulating layer on the first insulating layer;
Forming a through hole communicating with one end of the magnetic circuit in the first insulating layer and the second insulating layer;
The magnetic material is disposed in the through hole, the other end of the magnetic circuit made of the magnetic material is formed at a position corresponding to the through hole on the second insulating layer, and the second insulating layer is formed on the second insulating layer. Forming an auxiliary magnetic pole of the recording magnetic field generating portion at a position facing the main magnetic pole in
A method for manufacturing a near-field optical head, comprising: A near-field optical head according to claim 1 Symbol placement;
The near-field optical head is supported on the front end side so as to be movable in a direction parallel to the surface of the magnetic recording medium and rotatable about two axes parallel to the surface of the magnetic recording medium and orthogonal to each other. With the beam;
A light source that causes the light beam to enter the optical waveguide portion;
An actuator for supporting the base end side of the beam and moving the beam in a direction parallel to the surface of the magnetic recording medium;
A rotation drive unit for rotating the magnetic recording medium in the fixed direction;
A controller for controlling the operation of the recording magnetic field generator and the light source;
An information recording / reproducing apparatus comprising:

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