Near field light generating element, thermally assisted magnetic head, thermally assisted magnetic head device and thermally assisted magnetic recording/reproducing apparatus

A near-field light generating element includes a plasmon generator, and the plasmon generator has a base plate and a protrusion. The protrusion protrudes from one side of the base plate, wherein when H represents a height direction of the protrusion from the one side and W represents a width direction perpendicular to the height direction (H), a section taken along a W-H plane is of a rectangular shape whose opposite corners in the height direction (H) are rounded.

TECHNICAL FIELD

The present invention relates to a near-field light generating element, a thermally assisted magnetic head, a thermally assisted magnetic head device and a thermally assisted magnetic recording/reproducing apparatus.

BACKGROUND OF THE INVENTION

For increasing the recording density of magnetic recording, it is required to locally heat a magnetic recording medium and decrease the coercivity of the magnetic recording medium for facilitating recording. For local heating, it is desirable to use a near-field light.

Japanese Unexamined Patent Application Publication No. 2001-255254 and Japanese Patent Nos. 4032689 and 4104584 disclose a technology of generating a near-field light using surface plasmon with a metallic scatterer (plasmon generator in the present invention) irradiated with a light.

In generating a near-field light, the feature that the surface plasmon tends to propagate along a sharp edge in a concentrated manner should be utilized, so that in order to provide the metallic scatterer with a sharp edge, it is effective to modify its shape into a triangular prism.

On the other hand, however, since the edge tends to overheat excessively, thermal deformation of the metallic scatterer becomes a major problem.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a near-field light generating element in which a plasmon generator of the near-field light generating element has a base plate with a protrusion protruding therefrom and corners of the protrusion have a radius of curvature so that an intense near-field light can be generated while suppressing thermal deformation of the plasmon generator, a thermally assisted magnetic head, a thermally assisted magnetic head device and a thermally assisted magnetic recording/reproducing apparatus.

In order to attain the above object, a near-field light generating element according to the present invention comprises a plasmon generator. The plasmon generator has a base plate and a protrusion. The protrusion protrudes from one side of the base plate, wherein when H represents a height direction of the protrusion from the one side and W represents a width direction perpendicular to the height direction (H), a section taken along a W-H plane is of a rectangular shape whose opposite corners in the height direction (H) are rounded.

With the protrusion thus provided in the base plate, a highly intense near-field light can be generated from the near-field light generating element. This also can narrow a near-field light generating area. Moreover, the waveguide efficiency can also be improved for an incident light. As used herein, the waveguide efficiency refers to a ratio of output energy of a near-field light to input energy of an incident light.

Since the opposite corners are arcuate (with a radius of curvature R) in the W-H section of the protrusion, furthermore, thermal deformation of the opposite corners can be prevented to realize a plasmon generator which can endure long-term continuous use.

In addition, it may be configured such that one end face of the plasmon generator in a length direction (L) perpendicular to both the height direction (H) and the width direction (W) is a near-field light generating end face and the near-field light generating end face is coplanar with one end face of the base plate that is adjacent to one edge of the one side. With this configuration, the near-field light can be generated in a concentrated manner from the near-field light generating end face around the top of the protrusion in the height direction (H).

Moreover, if one end face of the protrusion in a length direction (L) perpendicular to both the height direction (H) and the width direction (W) is a near-field light generating end face and the near-field light generating end face of the protrusion protrudes by a distance X from one end face of the base plate that is adjacent to one edge of the one side, the near-field light generating position can be shifted closer to the base plate from around the top. In this case, a higher light intensity and improvement in waveguide efficiency can be achieved as compared with the above configuration where the near-field light generating end face is coplanar with one end face of the base plate that is adjacent to one edge of the one side (that is, the distance X is 0 nm).

In these configurations, the opposite corners preferably have a radius of curvature R equal to or less than 90% of half a length of the shorter one of a height H1in the height direction (H) and a width W1in the width direction (W) so as to prevent thermal deformation of the opposite corners in the W-H section of the protrusion more effectively. In this case, as a specific value, the radius of curvature R is preferably such that R≧5 nm, more preferably such that 5 nm≧R≧13.5 nm. With such a value, both the light intensity and the waveguide efficiency can be increased while preventing thermal deformation of the opposite corners in the W-H section of the protrusion.

The near-field light generating element may be configured to include an optical waveguide, wherein the plasmon generator is optically connected to the optical waveguide and the optical waveguide is opposed to the rectangular protrusion.

With the optical waveguide, an incident light can be accurately guided to the plasmon generator. Since the plasmon generator is optically connected to the optical waveguide, moreover, the incident light propagating through the optical waveguide can be evanescent-coupled to the plasmon generator, whereby a near-field light can be emitted from the plasmon generator.

In addition, the near-field light generating element may be configured to include a metal guide and an optical waveguide. In this case, preferably, the metal guide is opposed to the protrusion and optically connected to the base plate and the protrusion, while the optical waveguide is optically connected to the metal guide and located on the other side of the base plate of the plasmon generator opposite from the one side.

The near-field light generating element according to the present invention may be combined with a recording element to provide a thermally assisted magnetic head, and the thermally assisted magnetic head may be combined with a support device to provide a thermally assisted magnetic head device, and the thermally assisted magnetic head device may be combined with a magnetic recording medium to provide a magnetic recording/reproducing apparatus.

The other objects, constructions and advantages of the present invention will be further detailed below with reference to the attached drawings. However, the attached drawings show only illustrative examples.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring toFIG. 1, illustrated is a plasmon generator to be used in a near-field light generating element according to the present invention. The plasmon generator is configured to have a protrusion112protruding from one side of a base plate111.

InFIG. 1, H represents a height direction of the protrusion112from the one side of the base plate111, W represents a width direction perpendicular to the height direction (H), and L represents a length direction perpendicular to both the height direction (H) and the width direction (W). Also inFIG. 2and the following figures, these directions are denoted by the same manner.

At first, the principle of near-field light generation in the near-field light generating element according to the present invention will be described with reference toFIG. 1. When an incident light91enters a propagation path of the incident light (not shown) while satisfying the conditions of total reflection, electromagnetic field (near-field) leaks to the side of the plasmon generator. This near-field propagates along the surface of the plasmon generator as an evanescent wave (also called “evanescent light”)93to excite surface plasmon in the plasmon generator. The surface plasmon is a compressional wave of free charge on the surface of the plasmon generator and can be excited by vibrating the free charge on the surface of the plasmon generator with the evanescent wave93(evanescent coupling). The excited surface plasmon propagates along the surface of the plasmon generator in a direction opposite to the length direction (L) and is emitted as a near-field light92from a near-field light generating end face13.

InFIG. 1, one end face of the plasmon generator in the length direction (L) is the near-field light generating end face13. The near-field light generating end face13includes a near-field light generating end face131of the base plate111and a near-field light generating end face132of the protrusion112.

Generally, the surface plasmon tends to propagate along a sharp edge in a concentrated manner, and therefore in the case where the protrusion112is provided in the base plate111, as shown inFIG. 1, it propagates along the protrusion112in a concentrated manner, so that the near-field light92can be generated in a concentrated manner from the near-field light generating end face132of the protrusion112. Thus, the near-field light92generating area becomes small to increase the light intensity, which makes it possible to locally heat an object. In this case, moreover, the waveguide efficiency can also be improved.

FIG. 2shows a W-H section of the protrusion112taken along the line2-2inFIG. 1. As indicated by a solid line, the feature of the present invention resides in that opposite corners116,117in the W-H section of the protrusion112are arcuate with a radius of curvature R. Specifically, opposite corners (dotted lines) of a rectangular shape having a width W1and a height H1are rounded with a radius of curvature R.

In this specification, moreover, the W-H section of the protrusion112includes the near-field light generating end face132of the protrusion112, and the width W1and the height H1of the W-H section of the protrusion112may vary arbitrarily in the length direction (L).

With the W-H section of the protrusion112thus shaped, the surface plasmon can readily propagate along a top113. As a result, the near-field light can be generated in a concentrated manner around the top113in the near-field light generating end face132of the protrusion112, which further narrows the near-field light generating area. The near-field light generating area is smaller and the light intensity and the waveguide efficiency are higher than in the case where the W-H section of the protrusion112is of a triangular shape, for example.

In the case where the opposite corners116,117are arcuate with a radius of curvature R, as in the present invention, moreover, thermal deformation of the opposite corners116,117can be prevented effectively as compared with the case where the opposite corners116,117are right-angled (with a sharp edge) as indicated by dotted lines.

Generally, since the surface plasmon has the property of propagating along a sharp edge in a concentrated manner, there is a problem that the edge portion will be excessively overheated to cause thermal deformation. In order to solve such a problem, accordingly, the sharp edges are rounded in the present invention. By rounding the sharp edges, the surface plasmon can be dispersed over the opposite corners116,117and also to the top113, thereby preventing thermal deformation of the opposite corners116,117. This makes it possible to provide a plasmon generator which can endure long-term continuous use.

Moreover, the arcuate opposite corners116,117has two centers of curvature C1, C2within the protrusion, wherein the radius of curvature R should be equal to or less than half a length of the shorter one of the width W1and the height H1. This is because, with this configuration, the top113and opposite ends114,115can be smoothly connected to each other through the opposite corners without creating any sharp edge. It should be noted that when the opposite corners116,117are not configured as above, even if the opposite corners114,115are arcuate, a sharp edge will be created by rough connection between the top113and the opposite ends114,115, causing the problem of thermal deformation at the edge portion.

The plasmon generator preferably is comprised of Au, Ag or an alloy containing it as a main component. Among them, preferably, an Ag alloy contains at least one element selected from the group consisting of Pd, Au, Cu, Ph and Ir.

FIG. 3is a perspective view showing a near-field light generating element according to the present invention. Referring toFIG. 3, the near-field light generating element is a combination of a plasmon generator11and an optical waveguide15. The plasmon generator11is the same as shown inFIG. 1, wherein the W-H section of the protrusion112is of the same shape as indicated by a solid line inFIG. 2.FIG. 3shows a relative positional relationship between the plasmon generator11and the optical waveguide15but does not limit actual sizes of the plasmon generator11and the optical waveguide15.

The optical waveguide15for guiding the incident light91to the plasmon generator11is opposed to the protrusion112and optically connected to the plasmon generator11through an optical connection17. Since the plasmon generator11is optically connected to the optical waveguide15, the incident light91propagating through the optical waveguide15can be evanescent-coupled to the plasmon generator11, whereby the excited surface plasmon propagates through the protrusion112and the near-field light is emitted from the near-field light generating end face13.

The optical connection17serves to enable evanescent-coupling of the incident light91to the plasmon generator11. Moreover, the optical connection17has a lower refractive index than the optical waveguide15. For example, when it comprises a dielectric material and the incident light is a laser beam having a wavelength of 600 nm and the optical waveguide is comprised of TaOx(refractive index n=2.16), a clad layer may be comprised of SiO2(n=1.46) or Al2O3=1.63).

Furthermore, the optical waveguide15is covered with a clad layer (not shown) except for the optical connection17. The refractive index of the clad layer is lower than the refractive index of the optical waveguide15. With this configuration, the propagation loss of the incident light can be reduced by good optical properties of the material itself. That is, high propagation efficiency of the incident light91can be realized by the effect of confining the incident light91due to the difference in refractive index, which results in increasing the waveguide efficiency. For example, the optical waveguide15comprises a dielectric material. For example, when the incident light91has a wavelength of 600 nm and the clad layer comprises Al2O3 (n=1.63), the optical waveguide15may comprise SiOxNy(n=1.7 to 1.85), TaOx(n=2.16), NbOx(n=2.33) or TiOx(n=2.3 to 2.55). Thus, total reflection conditions can be satisfied at all sides of the optical waveguide15.

FIG. 4is a drawing in which the near-field light generating element shown inFIG. 3is seen from the side of the near-field light generating end face13in a planar manner. Since the surface plasmon tends to propagate along the top113of the protrusion112, as described above, the near-field light is generated at a generating area S1around the top113of the near-field light generating end face132.

FIG. 5is a graph showing a relationship between the radius of curvature R and the light intensity and waveguide efficiency of the near-field light generated at the generating area S1inFIG. 4, wherein the width W1and the height H1of the protrusion112at the W-H section satisfy H1>W1and the width W1and the height H1of the protrusion112at the near-field light generating end face132satisfy the relationship of W1=30 nm (<H1). InFIG. 5, the abscissa shows the radius of curvature R, the left ordinate shows the light intensity normalized with the maximum value taken as 1, and the right ordinate shows the waveguide efficiency normalized with the maximum value taken as 1. The light intensity is indicated by a solid line L11, while the waveguide efficiency is indicated by an alternate long and short dash line L21. From this, it is seen that the light intensity and the waveguide efficiency become maximum when R=12 nm. The light intensity is high in the range of R≦12.5 nm (particularly, 5 nm≦R≦13.5 nm) but drops to a low level when R>13.5 nm.

Accordingly, it is seen that as a condition for obtaining a near-field light excellent in both the light intensity and the waveguide efficiency, it is preferable that 5 nm≦R≦13.5 nm. That is, the radius of curvature R is preferably equal to or less than 90% of the width W1, and particularly, it is preferable that R=12 nm.

FIG. 6is a perspective view showing another embodiment of a near-field light generating element according to the present invention. Referring toFIG. 6, there is shown a state where the near-field light generating end face131of the base plate111is recessed from the near-field light generating end face132of the protrusion112by a distance X in the length direction (L). This state can also be expressed such that the near-field light generating end face132of the protrusion112projects by a distance X from the near-field light generating end face131of the base plate111. In addition, an optical connection (not shown) is provided between the plasmon generator11and the optical waveguide15. It should be noted that the same explanation as forFIG. 3is applicable to the portions similar to those inFIG. 3.

FIG. 7is a drawing in which the near-field light generating element shown inFIG. 6is seen from the side of the near-field light generating end face13in a planar manner. InFIG. 7, the near-field light can be generated at a generating area S2around a bottom118of the near-field light generating end face132of the protrusion112because the base plate111is recessed by a distance X inFIG. 6. As compared with the near-field light generating area S1inFIG. 4, the generating area S2inFIG. 7is shifted from the top113to the bottom118.

FIG. 8is a graph showing the light intensity of the near-field light generated at the generating area S2inFIG. 7, wherein the distance X and the width W1of the near-field light generating end face132of the protrusion112inFIG. 6are such that X=30 nm and W1=30 nm (<H1). The abscissa shows the radius of curvature R, and the ordinate shows the light intensity normalized with the maximum value taken as 1. A solid line L12indicates a case where X=30 nm, while a dotted line L11indicates a case where X=0 nm (i.e., corresponding to the solid line L11inFIG. 5).

On the other hand,FIG. 9is a graph showing the waveguide efficiency of the near-field light generated at the generating area S2inFIG. 7, wherein the distance X and the width W1of the near-field light generating end face132of the protrusion112inFIG. 6are such that X=30 nm and W1=30 nm (<H1). The abscissa shows the radius of curvature R, and the ordinate shows the waveguide efficiency normalized with the maximum value taken as 1. A solid line L22indicates a case where X=30 nm, while a dotted line L21indicates a case where X=0 nm (i.e., corresponding to the alternate long and short dash line L21inFIG. 5).

Referring toFIGS. 8 and 9, the same tendency is seen in both X=0 nm and X=30 nm, wherein the maximum value is obtained around R=12 nm. It is also seen that in the range of 0≦nm R≦12 nm, the difference from the maximum value is smaller in the case of X=30 nm than in the case of X=0 nm.

It should be noted that the same explanation as forFIGS. 5,8and9is also applicable to the case where the width W1and the height H1of the section of the protrusion satisfy the relationship of W1≧H1(=30 nm).

FIG. 10shows another embodiment of a plasmon generator according to the present invention. The portions similar to those inFIG. 1are denoted by the same reference symbols. One side of the base plate111is composed of a low-level portion117and a high-level portion118rising perpendicularly from the low-level portion117. The protrusion112protrudes from the one side of the base plate111over the low-level portion117and the high-level portion118. L1represents a length of the plasmon generator as measured in the length direction (L). End faces of the protrusion112and the base plate111opposite to the length direction (L) serve as the near-field light generating end face13. The near-field light generating end face13includes the near-field light generating end face131of the base plate111and the near-field light generating end face132of the protrusion112. The H—W section of the protrusion112is of the same shape as indicated by the solid line inFIG. 2.

Moreover, the plasmon generator preferably is comprised of Au, Ag or an alloy containing it as a main component. Among them, preferably, an Ag alloy contains at least one element selected from the group consisting of Pd, Au, Cu, Rh and Ir.

FIG. 11is a perspective view showing another embodiment of a near-field light generating element according to the present invention. Referring toFIG. 11, the near-field light generating element is a combination of the plasmon generator11, the optical waveguide15and a metal guide19. The plasmon generator is the same as shown inFIG. 10. In the near-field light generating element, the optical waveguide15, the plasmon generator11and the metal guide19are arranged in order in the height direction (H) and a top surface119of the protrusion112is opposed to the metal guide19with a gap G1. Moreover, the plasmon generator11is the same as shown inFIG. 10.

The metal guide19is optically connected to the plasmon generator11and the optical waveguide15through the optical connection17. In addition, the metal guide19has a length L2as measured in the length direction (L) and a width W2as measured in the width direction (W). As measured in the height direction (H), moreover, the metal guide19has a constant thickness H2from one end face191to a position PO1over a distance L21, but the portion from the position PO1to the other end face192may be designed to have a thickness that is larger than the thickness H2.

The optical connection17has a lower refractive index than the optical waveguide15. For example, when it comprises a dielectric material and the incident light is a laser beam having a wavelength of 600 nm and the optical waveguide is comprised of TaOx(refractive index n=2.16), a clad layer may be comprised of SiO2(n=1.46) or Al2O3(n=1.63).

In the case where the near-field light generating element is configured as inFIG. 11, since the waveguide efficiency can be improved as compared with the near-field light generating elements shown inFIGS. 3 and 6, the output power of the incident light can be reduced.

It should be noted thatFIG. 11shows a relative positional relationship among the plasmon generator11, the optical waveguide15and the metal guide19but does not limit actual sizes of the plasmon generator11, the optical waveguide15and the metal guide19.

FIG. 12is a plan view in which the near-field light generating element shown inFIG. 11is seen from the side of the near-field light generating end face13.FIG. 13is a sectional view take along the line13-13inFIG. 12.

Referring toFIG. 12, the near-field light is generated at a generating area S3around the top of the protrusion112in the height direction (H) in the near-field light generating end face132of the near-field light generating end face13. Referring toFIG. 13, moreover, the incident light91propagating through the optical waveguide15leaks out as a near field from the optical waveguide15to the optical connection17. This near field passes through the optical connection17and reaches the metal guide19as the evanescent light93. Furthermore, the evanescent light93propagates along the surface of the metal guide19, passes through the optical connection17once again and then propagates along the surface of the protrusion112of the plasmon generator11. Then, the evanescent light93is evanescent-coupled to the protrusion112to excite surface plasmon in the plasmon generator11. The excited surface plasmon propagates through the protrusion112and is emitted as the near-field light92from the near-field light generating end face132of the protrusion112.

With such specific dimensions, the maximum optical power density and waveguide efficiency were measured by varying the radius of curvature R at the opposite corners of the W-H section of the protrusion112, andFIG. 14shows their results. InFIG. 14, the abscissa shows the radius of curvature R, the left ordinate shows the maximum optical power density, and the right ordinate shows the waveguide efficiency. The maximum optical power density is indicated by a solid line L13, while the waveguide efficiency is indicated by an alternate long and short dash line L23. Referring toFIG. 14, the maximum optical power density and the waveguide efficiency become maximum when the radius of curvature R=9 nm.

2. Thermally Assisted Magnetic Head

The present invention also discloses a thermally assisted magnetic head. The thermally assisted magnetic head includes the foregoing near-field light generating element.FIG. 15shows the appearance of the thermally assisted magnetic head according to the present invention.FIG. 16is a partially omitted sectional side view ofFIG. 15, schematically showing a configuration of a head element part and its surroundings. The thermally assisted magnetic head is to be used in combination with a rapidly spinning magnetic recording medium such as a hard disk, and thermally assisted magnetic heads of this type are generally called “floating-type”. Hereinbelow, the thermally assisted magnetic head according to the present invention will be described with reference toFIGS. 15 and 16.

A thermally assisted magnetic head3comprises a slider32and a light source unit31. The slider32has a slider substrate33and a head element part34, wherein the head element part34is located at a trailing-side end of the slider substrate33as seen in an airflow direction A1in a medium-facing surface321of the slider32. The head element part34includes a near-field light generating element1, a recording element35and a reproducing element39. The near-field light generating element1includes the plasmon generator11and the optical waveguide15. The plasmon generator11has the near-field light generating end face13. The near-field light generating element1may adopt the structures shown inFIGS. 3,6and11to include an optical connection and a metal guide.

The slider32comprises Al2O3—TiC or the like. The medium-facing surface321is an air bearing surface (ABS) and geometrically shaped (omitted in the drawings) so as to control floating characteristics.

The near-field light generating element1, the recording element35and the reproducing element39constituting the head element part34are stacked on the trailing side of the slider substrate33, which is the side having an air outflow end, by using high-precision patterning technologies including a photolithography process and covered with an insulating protective film such as alumina. Typically, the recording element35has a magnetic circuit and a magnetic pole structure suitable for perpendicular magnetic recording.

The near-field light generating element1emits the incident light91as a near-field light from the near-field light generating end face13laying in the medium-facing surface321of the head element part34. A magnetic recording layer of a magnetic recording medium can be heated by the near-field light.

The recording element35is disposed adjacent the near-field light generating element1so as to perform magnetic recording on the magnetic recording layer whose coercivity has been lowered by heating with the near-field light.

The light source unit31comprises a laser diode chip (hereinafter referred to as LD chip)312and a holder311supporting it and is disposed on a back surface of the slider32opposite from the ABS321. The LD chip312is optically connected to the waveguide15. The LD chip312has a laser diode within. The laser diode may be one from which a laser beam having a wavelength within the range of 375 nm to 1.7 μm can be emitted as the incident light91. Specifically, it may be an InP-based, GaAs-based or GaN-based laser diode, for example.

At one end face, the holder311is joined to the back surface of the slider32, for example, through an adhesive or solder. In general, the holder311is provided with a monitor for monitoring and controlling the intensity of the incident light91(laser beam) emitted from the laser diode of the LD chip312or the like.

The reproducing element39includes an MR stack391, a lower shield layer392, an upper shield layer393and a reproducing element insulating layer394and is formed on a foundation layer395comprising an insulating material such as Al2O3. The MR stack391is a magneto-sensitive part which senses a signal magnetic field by using the MR effect.

On the other hand, the recording element35includes a main pole351, a leading shield352, a write coil layer353, an upper yoke layer354, a lower yoke layer355and a coil insulating layer3531. The main pole351comprises a soft magnetic material. Examples of the soft magnetic material include alloy materials such as FeNi, FeCo, FeCoNi, FeN and FeZrN.

On insulating layers3571to3573comprising an insulating material such as Al2O3, the write coil layer353is formed to pass through at least between the upper yoke layer354and the lower yoke layer355for every turn and wound about a back contact356. In the above, for example, the write coil layer353is covered with the coil insulating layer3531comprising a heat-cured insulating material such as photoresist, thereby providing electrical insulation between the write coil layer353and the upper yoke layer354. Although formed as a single layer in the present embodiment, the write coil layer353may have two or more layers or may be a helical layer. Moreover, the number of turns is not limited and may be set to 2 to 7 turns, for example.

The back contact356has a through hole3561, and the optical waveguide15and a through hole insulating layer3562covering the optical waveguide15extend through the through hole3561.

The leading shield352is located on a leading side of the main pole351and magnetically connected to the main pole351. The leading shield352serves the function of taking in a recording magnetic field spreading from the main pole351, wherein effective magnetic field gradient increases with an increase in recording magnetic field gradient, which results in increasing recording density. The leading shield352preferably comprises NiFe or CoNiFe having a high saturation magnetic flux density or an iron-based alloy material similar to that of the main pole351.

After the spot size has been converted by a spot size convertor37, the incident light91from the light source unit31enters a light-receiving end face151of the optical waveguide15and propagates through the optical waveguide15. The optical waveguide15extends from the light-receiving end face151, through the through hole3561provided in the back contact356, to an end face of the head.

The plasmon generator11converts the incident light91having propagated through the optical waveguide15to a near-field light and emits the near-field light from the near-field light generating end face13.

Moreover, an inter-element shield layer396sandwiched between the insulating layers394,397is disposed between the reproducing element39and the lower yoke layer355. The inter-element shield layer396can comprise a soft magnetic material and serves to shield the reproducing element39against a magnetic field generated from the recording element35.

3. Thermally Assisted Magnetic Head Device

The present invention also discloses a thermally assisted magnetic head device. The thermally assisted magnetic head device includes a thermally assisted magnetic head and a head support device. Head support devices are designed to support the head in such a manner as to permit rolling and pitching of the head and include an HGA (head gimbal assembly) and an HAA (head arm assembly).

FIG. 17is a perspective view of an HGA according to the present invention. Referring toFIG. 17, the HGA includes the thermally assisted magnetic head3, a head support device (gimbal)71and a suspension711. The suspension711has a load beam712and a flexure713. The flexure713is formed from a thin leaf spring and attached at one side to the load beam712. The thermally assisted magnetic head3is attached to the other side of the flexure713. The thermally assisted magnetic head3is attached to one side of the flexure713by means of an adhesive or the like. The thermally assisted magnetic head3is the same as shown inFIGS. 15 and 16, and a flexible cable part714or the like is connected to it.

FIG. 18is a perspective view of an HAA according to the present invention. Referring toFIG. 18, the HAA includes an HGA72and an arm731. The arm731is integrally formed using a suitable non-magnetic metallic material such as aluminum alloy. The arm731has an attachment hole732. HGA72is the same as shown inFIG. 17and has one end secured to the arm731, for example, with a ball connecting structure.

The present invention further discloses a thermally assisted magnetic recording/reproducing apparatus.FIG. 19is a perspective view of a thermally assisted magnetic recording/reproducing apparatus according to the present invention and shows a typical structure of a thermally assisted magnetic recording/reproducing apparatus. This thermally assisted magnetic recording/reproducing apparatus is, for example, a hard disk drive.

Referring toFIG. 19, the thermally assisted magnetic recording/reproducing apparatus includes HAA73and magnetic recording media81. In the thermally assisted magnetic recording/reproducing apparatus, for example, the magnetic recording media81and the HAA73are provided within a case83.

The magnetic recording media81are rotatable about a spindle motor84which is fixed to the case83. The HAA73are the same as shown inFIG. 18, and the arms731are connected to an assembly carriage85and pivotable about a pivot bearing86which is fixed to the case83. Furthermore, the HAA73has the thermally assisted head3, and this thermally assisted magnetic head3is the same as shown inFIGS. 15 and 16.

The assembly carriage85includes, for example, a driving source such as a voice coil motor. For example, this thermally assisted magnetic recording/reproducing apparatus is of the type in which a plurality of the arms731are integrally pivotable about the pivot bearing86. InFIG. 19, the case83is shown in a partially cut-away state, making it easy to see the internal structure of the thermally assisted magnetic recording/reproducing apparatus.

When the magnetic recording medium81rotates for recording or reproducing information, the thermally assisted magnetic head3takes off from the recording surface of the magnetic recording medium81utilizing an air flow generated between the recording surface of the magnetic recording medium81and the ABS321and then performs magnetic recording or reproducing operations. Moreover, the thermally assisted magnetic head3is connected to a control circuit82, and the control circuit82controls magnetic recording and reproducing operations with the magnetic recording medium81.

The present invention has been described in detail above with reference to preferred embodiments. However, obviously those skilled in the art could easily devise various modifications of the invention based on the technical concepts underlying the invention and teachings disclosed herein.