Tapered optical and magnetic elements for improved writing in heat-assisted magnetic recording

Abstract

The purpose of this disclosure is to provide a heat-assisted magnetic recording (HAMR) writer head with high magnetic field reliability and high accuracy. [Solution] Disclosed are a writer head for a heat-assisted magnetic recording device and a method for manufacturing a writer head. The writer head comprises a plurality of layers, including a waveguide cutoff layer, a waveguide layer, a near-field transducer layer, a heat sink layer, and a peg layer. Each layer has a tapered angle near the air bearing surface. The writer head further has a principal axis pole adjacent to an optical component having a similar tapered angle near the air bearing surface.

Description

Technical Field

[0001] The present disclosure relates to a high-performance heat-assisted magnetic recording (HAMR) writer head and a method for fabricating a HAMR writer head for use, for example, in a hard disk drive (HDD).

Background Art

[0002] A magnetic writer head is an important component of an HDD and converts an electric current in a coil into a strong magnetic field applied to a media platter for efficient and high-density information writing. As the technology of HDDs has advanced, higher areal density capacity (ADC) has been required. One way to increase the ADC, that is, the amount of data per square inch, is to reduce the particle size of the media platter.

[0003] The growth of ADC greatly depends on the reduction of media bits and the reduction of the writer head structure to accommodate smaller particles. To maintain the stability of the electron bits on the media when the particle size is decreasing, it is necessary for the media particles to have a larger anti-electric field. However, limits occur due to the degradation of magnetic performance in a reduced writer head operating at GHz frequencies.

[0004] Writer heads used in perpendicular magnetic recording (PMR) apply a perpendicular magnetic field to the media bits using a main pole (MP). However, as the size is reduced, especially when the particles on the media become smaller with greater coercivity, the writability substantially decreases. Heat-assisted magnetic recording (HAMR) and microwave-assisted magnetic recording (MAMR) technologies use energy sources (from heat and microwaves, respectively) to temporarily soften the media, and as a result, the magnetic field from the miniaturized writer head is sufficient for efficient writing operation.

[0005] Heat-assisted magnetic recording (HAMR) technology provides a way to substantially increase the amount of data that can be stored on an HDD. A HAMR writer head consists of a miniature laser diode that can temporarily transfer heat to small particles on a media platter to reduce the switching magnetic field, and a magnetic writer element that applies magnetic flux to the heated media particles to write information. The sharp thermal gradient, which translates into a high magnetic gradient on the media, enables higher data storage densities than those achievable with conventional perpendicular magnetic recording technology. Improvements to writer head technology are needed. [Overview of the project]

[0006] In some embodiments, the technology described herein relates to a writer head for a heat-assisted magnetic recording (HAMR) device, comprising an optical component including a triangular layer having a tapered edge and a waveguide (WG) layer disposed adjacent to the triangular layer, wherein the WG layer comprises a flat section and a tapered section, the tapered section having a tapered angle and in contact with the tapered edge of the triangular layer, a cladding layer disposed adjacent to the WG layer, and a near-field transducer disposed adjacent to the cladding layer. The present invention relates to a writer head comprising: a transducer (NFT) layer, which includes a tapered section including a tapered angle; a heat sink layer disposed adjacent to the NFT layer; a peg layer disposed adjacent to the heat sink layer, which includes an insulator and a tapered section including a tapered angle; and a magnetic component comprising a main magnetic pole having a saturation magnetization of about 24 kG or more, which has a first tapered section including a tapered angle and a main magnetic pole section substantially parallel to a flat section of the WG layer.

[0007] In some embodiments, the technology described herein relates to a writer head having a taper angle of about 20 degrees to about 70 degrees. In some embodiments, the technology described herein relates to a writer head in which the triangular layer includes a waveguide blocker layer containing ruthenium.

[0008] In some embodiments, the technology described herein relates to a lighter head in which a triangular layer comprises one or more alumina or silica. In some embodiments, the technology described herein relates to a lighter head in which the NFT layer comprises a first NFT layer comprising a first metal and a second NFT layer comprising a transition metal, wherein the first NFT layer comprises one or more of gold, silver, copper, alloys thereof, graphene, and metal oxides, and the second NFT layer comprises one of Rh or Ir.

[0009] In some embodiments, the technology described herein relates to a lighter head in which the heat sink layer comprises one or more of gold, ruthenium, aluminum nitride, or silicon carbide. In some embodiments, the technology described herein relates to a writer head in which the optical components further include a first oxide layer disposed between an NFT layer and a heat sink layer.

[0010] In some embodiments, the technology described herein relates to a writer head in which the tapered section of the main magnetic pole includes a taper angle. In some embodiments, the technology described herein relates to a writer head in which the first tapered section of the main magnetic pole has a thickness of about 20 nm to about 100 nm.

[0011] In some embodiments, the technology described herein relates to a writer head in which the ratio of the thickness of the first tapered section of the main magnetic pole to the average particle size of the recording medium is about 1.4 to about 14.

[0012] In some embodiments, the technology described herein relates to a writer head in which the main pole section has a thickness of about 200 nm to about 600 nm. In some embodiments, the technology described herein relates to a writer head in which the ratio of the thickness of the main pole section of the main pole to the average particle size of the recording medium is about 29 to about 86.

[0013] In some embodiments, the technology described herein relates to a writer head in which the main magnetic pole includes a second tapered section having the same taper angle as the first tapered section. In some embodiments, the technology described herein relates to a writer head in which a second tapered section of the main magnetic pole has a thickness of about 20 nm to about 100 nm.

[0014] In some embodiments, the technology described herein relates to a writer head in which the ratio of the thickness of the second tapered section of the main magnetic pole to the average particle size of the recording medium is about 1.4 to about 14.

[0015] In some embodiments, the technology described herein relates to a writer head in which the optical components further include a laser diode configured to generate a light beam. In some embodiments, the technology described herein relates to a writer head in which the magnetic component includes a first return pole operably connected to a principal pole by a first connector and located on the side of the principal pole opposite the optical component.

[0016] In some embodiments, the technology described herein relates to a writer head in which the distance between the first return pole and the principal pole is about 50 nm to about 1,000 nm. In some embodiments, the technology described herein relates to a writer head in which the first return pole has a thickness of about 500 nm to about 1,500 nm.

[0017] In some embodiments, the technology described herein relates to a writer head in which the first return pole includes a first pedestal having a thickness of about 1.5 μm to about 2.5 μm and a height of about 200 nm to about 1,000 nm.

[0018] In some embodiments, the technology described herein relates to a writer head in which the first return pole further includes a first magnetic leading shield (MLS) having a thickness of about 100 nm to about 1,000 nm and a height of about 500 nm to about 2,000 nm.

[0019] In some embodiments, the technology described herein relates to a writer head in which the magnetic components include a first yoke positioned between a first connector and a main magnetic pole. In some embodiments, the technology described herein relates to a writer head in which the magnetic components include a second return pole operably connected to a main pole by a second connector and located on the side of the main pole opposite the first return pole.

[0020] In some embodiments, the technology described herein relates to a writer head in which the distance between the second return pole and the main pole is from about 100 nm to about 2,000 nm. In some embodiments, the technology described herein relates to a writer head in which the second return pole has a thickness of from about 100 nm to about 1,500 nm.

[0021] In some embodiments, the technology described herein relates to a writer head in which the second return pole includes a second pedestal having a thickness of from about 1.5 μm to about 2.5 μm and a height of from about 200 nm to about 1,000 nm.

[0022] In some embodiments, the technology described herein relates to a writer head in which the second return pole further includes a second magnetic leading shield (MLS) having a thickness of from about 100 nm to about 800 nm and a height of from about 500 nm to about 1,000 nm.

[0023] In some embodiments, the technology described herein relates to a writer head in which the magnetic component further includes a coil including from 0 to 6 loops, and the coil is disposed between the first return pole and the main pole.

[0024] In some embodiments, the technology described herein relates to a writer head in which the magnetic component further includes a first coil and a second coil, the combined first coil and second coil includes from 0 to 6 loops, the first coil is disposed between the first return pole and the main pole, the second coil is disposed between the second return pole and the main pole, and the first coil and the second coil include the same number of loops.

Brief Description of the Drawings

[0025] [Figure 1A] An exemplary optical component for a writer head according to one embodiment is shown. [Figure 1B] An exemplary optical component for a writer head according to one embodiment is shown. [Figure 2A]An exemplary writer head according to one embodiment is shown. [Figure 2B] An exemplary writer head according to one embodiment is shown. [Figure 2C] An exemplary writer head according to one embodiment is shown. [Figure 2D] An exemplary writer head according to one embodiment is shown. [Figure 3] This shows a graphical representation of the performance metrics of a writer head according to one embodiment. [Figure 4] This shows a graphical representation of the performance metrics of a writer head according to one embodiment. [Figure 5] This shows a graphical representation of the performance metrics of a writer head according to one embodiment. [Modes for carrying out the invention]

[0026] This disclosure is not limited to the systems, devices, and methods described herein, as they are modifiable. The terms used herein are for illustrative purposes only and are not intended to limit the scope of any particular version or embodiment.

[0027] product A heat-assisted magnetic recording (HAMR) writer head can be assembled to assist in writing data onto a recording medium. In some embodiments, the writer head comprises an optical component and a magnetic component. The optical component may be configured to apply heat to the recording medium to soften it. The magnetic component may be configured to apply a concentrated magnetic flux to write data onto the heated recording medium. By using heat to soften the recording medium, the optical component enables the magnetic component to write data onto the recording medium more efficiently. Both the magnetic and optical components enable a higher storage density on the recording medium than writer head technologies that do not require a heating element.

[0028] Figures 1A and 1B show exemplary optical components for a HAMR writer head. In some embodiments, the optical components are positioned adjacent to the main magnetic pole 107. In some embodiments, the optical components include a laser diode configured to generate a light beam. In some embodiments, the optical components comprise multiple layers. In some embodiments, the optical components comprise a triangular layer 101 having a tapered edge. The triangular layer 101 may be configured to provide a tapered angle 110 to the layers of the optical components and the main magnetic pole 107. In some embodiments, the triangular layer comprises one of alumina or silica. The tapered angle 110 can be any angle effective in generating a target magnetic field. In some embodiments, the tapered angle 110 is about 20 to about 70 degrees, depending on the required performance. In some embodiments, the tapered angle is about 45 degrees.

[0029] In some embodiments, the triangular layer 101 may be a waveguide (WG) shielding layer. The waveguide shielding layer may be configured to prevent diffuse light from reaching the recording medium. The waveguide shielding layer may contain any material that substantially prevents diffuse light from reaching the recording medium. In some embodiments, the waveguide shielding layer contains a conductive material such as ruthenium. In some embodiments, the waveguide shielding layer is located near an air-bearing surface (ABS) 109.

[0030] In some embodiments, the optical component further comprises a waveguide layer 102 positioned adjacent to the triangular layer 101. The waveguide layer 102 may be operably connected to near-field transducer (NFT) layers 103, 104 and configured to direct light from the laser diode to the NFT layers 103, 104. In some embodiments, the waveguide layer 102 comprises an angled tapered section extending to or near the air bearing surface 109. In some embodiments, the angle of the tapered section is a tapered angle 110 determined by the tapered edge of the triangular layer 101. The waveguide layer 102 may further comprise a flat section substantially parallel to the rear of the principal magnetic pole 107. In some embodiments, the waveguide layer 102 has a thickness of about 50 nm to about 160 nm. In some embodiments, the waveguide layer has a thickness of about 120 nm.

[0031] In some embodiments, the thickness of the waveguide layer 102 is expressed as the ratio of the thickness of the waveguide layer 102 to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the waveguide layer 102 to the average particle size of the recording medium is about 7 to about 22.

[0032] In some embodiments, the optical component may further include a cladding layer 108 positioned between the waveguide layer 102 and the NFT layers 103, 104 and configured to bond the waveguide layer 102 and the NFT layers 103, 104. In some embodiments, the cladding layer 108 is positioned along the entire length of the waveguide layer 102. In some embodiments, the cladding layer 108 is positioned along a portion of the waveguide layer 102. In some embodiments, the cladding layer 108 is positioned near the air bearing surface 109. The cladding layer 108 may contain any material known to be effective in bonding the waveguide layer 102 and the NFT layers 103, 104. In some embodiments, the cladding layer 108 comprises an insulator. In some embodiments, the cladding layer 108 comprises a dielectric material. In some embodiments, the cladding layer 108 has a thickness of about 200 nm to about 1 μm. In some embodiments, the cladding layer has a thickness of about 400 nm.

[0033] In some embodiments, the thickness of the cladding layer 108 is expressed as the ratio of the thickness of the cladding layer 108 to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the cladding layer 108 to the average particle size of the recording medium is approximately 28 to approximately 143.

[0034] In some embodiments, the optical components further comprise near-field transducer (NFT) layers 103, 104. The NFT layers 103, 104 may be configured to focus laser-induced plasmons onto the recording medium. In some embodiments, the NFT layers 103, 104 may be configured to induce heating at nanoscale points on the recording medium, enabling magnetic recording on narrow tracks and high areal density capacitance (ADC). In some embodiments, the NFT layers 103, 104 comprise an angled tapered section extending to or near the air bearing surface 109. In some embodiments, the angle of the tapered section is a taper angle 110 determined by the tapered edge of the triangular layer 101. The NFT layers 103, 104 may further comprise a flat section substantially parallel to the rear of the principal magnetic pole 107. In some embodiments, the NFT layers 103, 104 have a thickness of about 17 nm to about 115 nm. In some embodiments, the NFT layers 103 and 104 include a first NFT layer 103 and a second NFT layer 104.

[0035] In some embodiments, the thickness of the NFT layers 103 and 104 is expressed as the ratio of the thickness of the NFT layers 103 and 104 to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the NFT layers 103 and 104 to the average particle size of the recording medium is approximately 2.5 to approximately 16.5.

[0036] In some embodiments, the first NFT layer 103 contains a metal having good optical and plasmon properties. In some embodiments, the first NFT layer 103 contains one or more of gold, silver, copper, their alloys, graphene, and metal oxides. In some embodiments, the first NFT layer 103 is recessed from the air bearing surface 109. In some embodiments, the first NFT layer 103 has a thickness of about 15 nm to about 100 nm. In some embodiments, the first NFT layer 103 has a thickness of about 55 nm.

[0037] In some embodiments, the thickness of the first NFT layer 103 is expressed as the ratio of the thickness of the first NFT layer 103 to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the first NFT layer 103 to the average particle size of the recording medium is about 2 to about 14.

[0038] In some embodiments, the second NFT layer 104 contains a robust transition metal. In some embodiments, the second NFT layer 104 contains either rhodium or iridium. In some embodiments, the second NFT layer 104 extends to the air bearing surface 109. In some embodiments, the second NFT layer 104 has a length of about 0.6 μm to about 1.0 μm. In some embodiments, the second NFT layer 104 has a thickness of about 2 nm to about 15 nm. In some embodiments, the second NFT layer 104 has a thickness of about 5 nm.

[0039] In some embodiments, the thickness of the second NFT layer 104 is expressed as the ratio of the thickness of the second NFT layer 104 to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the second NFT layer 104 to the average particle size of the recording medium is about 0.2 to about 2.

[0040] The NFT layers 103 and 104 may have any resistivity that is effective for focusing laser-induced plasmons onto the recording medium. In some embodiments, the NFT layers 103 and 104 have resistivity ranging from about 8.0 μΩ*cm to about 20.0 μΩ*cm.

[0041] In some embodiments, the optical component further comprises a heat sink layer 105. The heat sink layer 105 may be configured to extract heat from the main pole 107. The heat sink layer 105 may contain any material effective for use as a heat sink. In some embodiments, the heat sink layer 105 contains one or more of gold, ruthenium, aluminum nitride, hexagonal boron nitride, or silicon carbide. In some embodiments, the heat sink layer 105 comprises an angled tapered section extending to or near the air bearing surface 109. In some embodiments, the angle of the tapered section is a taper angle 110 determined by the tapered edge of the triangular layer 101. The heat sink layer 105 may further comprise a flat section substantially parallel to the rear of the main pole 107. In some embodiments, the heat sink layer does not extend to the air bearing surface 109. In some embodiments, the heat sink layer 105 has a thickness of about 10 nm to about 5 μm. In some embodiments, the heat sink layer 105 has a thickness of approximately 100 nm.

[0042] In some embodiments, the thickness of the heat sink layer 105 is expressed as the ratio of the thickness of the heat sink layer 105 to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the heat sink layer 105 to the average particle size of the recording medium is approximately 1.4 to approximately 500.

[0043] In some embodiments, the optical component further comprises a peg layer 106 configured to provide an insulator and isolate the optical component from the main magnetic pole 107. In some embodiments, the peg layer 106 comprises one of Ir or Rh. In some embodiments, the peg layer 106 extends to the air bearing surface 109. In some embodiments, the peg layer 106 is configured to isolate the NFT layers 103, 104 from the main magnetic pole 107. In some embodiments, the heat sink layer 105 may be in contact with the main magnetic pole 107. In some embodiments, the peg layer 106 is configured to isolate the NFT layers 103, 104 and the heat sink layer 105 from the main magnetic pole 107. In some embodiments, the peg layer 106 has a tapered edge having a taper angle 110 determined by the tapered edge of the triangular layer 101. In some embodiments, the peg layer 106 has a thickness of about 15 nm to about 100 nm. In some embodiments, the peg layer 106 has a thickness of about 30 nm.

[0044] In some embodiments, the thickness of the peg layer 106 is expressed as the ratio of the thickness of the peg layer 106 to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the peg layer 106 to the average particle size of the recording medium is about 2 to about 14.

[0045] In some embodiments, the optical component further includes a first oxide layer disposed between the NFT layers 103, 104 and the heat sink layer 105. In some embodiments, the first oxide layer is disposed along the entire length of the heat sink layer 105. In some embodiments, the first oxide layer is disposed along a portion of the length of the heat sink layer 105. In some embodiments, the first oxide layer comprises one of silica or alumina. In some embodiments, the first oxide layer has a thickness of about 1 nm to about 15 nm.

[0046] In some embodiments, the thickness of the first oxide layer is expressed as the ratio of the thickness of the first oxide layer to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the first oxide layer to the average particle size of the recording medium is about 0.1 to about 2.

[0047] In some embodiments, the optical component further includes a second oxide layer positioned between the heat sink layer 105 and the peg layer 106. In some embodiments, the second oxide layer is positioned along the entire length of the heat sink layer 105. In some embodiments, the second oxide layer is positioned along a portion of the length of the heat sink layer 105. In some embodiments, the second oxide layer comprises one of silica or alumina. In some embodiments, the second oxide layer has a thickness of about 1 nm to about 15 nm.

[0048] In some embodiments, the thickness of the second oxide layer is expressed as the ratio of the thickness of the second oxide layer to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the second oxide layer to the average particle size of the recording medium is about 0.1 to about 2.

[0049] The main magnetic pole 107 may be configured to apply concentrated magnetic flux to the recording medium. The main magnetic pole 107 may have any saturation magnetization effective for writing data onto the recording medium. Typically, the material of the main magnetic pole is the material with the highest available saturation magnetization. In some embodiments, the main magnetic pole 107 includes a material having a magnetic moment greater than about 24 kG. In some embodiments, the main magnetic pole 107 includes a two-layer material consisting of a 24 kG material and another thermally robust material having a lower magnetic moment in the range of 16–22 kG. In some embodiments, the high-moment material is placed closer to the NFT to achieve higher magnetic flux concentration. In some embodiments, the lower-moment material is placed closer to the NFT to achieve better lifetime.

[0050] In some embodiments, the main magnetic pole 107 comprises a first tapered section having a taper angle 110. In some embodiments, the first tapered section extends from near the air bearing surface 109 to the air bearing surface 109. In some embodiments, the thickness of the first tapered section is about 10 nm, about 100 nm. In some embodiments, the thickness of the first tapered section is about 40 nm.

[0051] In some embodiments, the thickness of the first tapered section is expressed as the ratio of the thickness of the first tapered section to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the first tapered section to the average particle size of the recording medium is about 1.4 to about 14.

[0052] In some embodiments, the main pole 107 further comprises a main pole section extending along the air bearing surface 109. In some embodiments, the main pole section has a thickness of about 200 nm to about 600 nm. In some embodiments, the main pole section has a thickness of about 300 nm.

[0053] In some embodiments, the thickness of the main pole section is expressed as the ratio of the thickness of the main pole section to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the main pole section to the average particle size of the recording medium is approximately 29 to approximately 86.

[0054] In some embodiments, the trailing edge 112 of the main magnetic pole 107 is flat and does not have a second tapered section. In some embodiments, the trailing edge 112 of the main magnetic pole 107 has a second tapered section having a second taper angle 111. The second taper angle 111 can be any angle effective for generating the target magnetic field. In some embodiments, the second taper angle 111 is about 20 degrees to about 70 degrees. In some embodiments, the second taper angle 111 is the same angle as the taper angle 110. In some embodiments, the thickness of the second tapered section is the same as the thickness of the first tapered section. In some embodiments, the second tapered section has a thickness of about 20 nm to about 100 nm. In some embodiments, the second tapered section has a thickness of about 40 nm.

[0055] In some embodiments, the thickness of the second tapered section is expressed as the ratio of the thickness of the second tapered section to the average particle size of the recording medium. In some embodiments, the ratio of the thickness of the second tapered section to the average particle size of the recording medium is about 1.4 to about 14.

[0056] Figures 2A to 2D show exemplary writer heads for HAMR devices. In some embodiments, the writer head comprises an optical component 201. The optical component can be any of the optical components 201 described above. The optical component 201 may be positioned adjacent to the main pole 202. In some embodiments, the optical component 201 is positioned at the bottom of the main pole 202. The main pole 202 can be the main pole 107 described above. In some embodiments, the optical component 201 and the main pole 202 extend to the air bearing surface 211. In some embodiments, the writer head comprises a first return pole 203 configured to allow the magnetic flux from the main pole 202 to complete a loop. In some embodiments, the first return pole 203 extends to the air bearing surface 211.

[0057] The distance between the principal pole 202 and the first return pole 203 can be selected to maximize the magnetic field at the recording point on the recording medium. In some embodiments, the first return pole 203 is located on the side of the principal pole 202 opposite the optical component 201. In such embodiments, the distance between the first return pole 203 and the principal pole 202 is not limited by the optical component 201. In some embodiments, the distance between the principal pole 202 and the first return pole 203 is about 50 nm to about 1,000 nm. In some embodiments, the distance between the principal pole 202 and the first return pole 203 is about 500 nm.

[0058] The first return pole 203 may have any thickness 213 that is effective in allowing the magnetic flux from the main pole 202 to complete the loop. In some embodiments, the first return pole 203 comprises a thickness 213 of about 500 nm to about 1,500 nm. In some embodiments, the first return pole 203 comprises a magnetic material having a saturation magnetization lower than the saturation magnetization of the main pole 202. In some embodiments, the first return pole 203 comprises a saturation magnetization of about 10 kG to about 22 kG. In some embodiments, the first return pole 203 comprises a saturation magnetization of about 19 kG.

[0059] In some embodiments, the first return pole 203 comprises a first pedestal 205 configured to determine the distance between the first return pole 203 and the main pole 202. In some embodiments, the first pedestal 205 is positioned adjacent to the air bearing surface 211. In some embodiments, the first pedestal 205 has a thickness 212 of about 1.5 μm to about 2.5 μm. In some embodiments, the first pedestal 205 has a thickness 212 of about 1 μm. In some embodiments, the first pedestal 205 has a height 216 of about 200 nm to about 1,000 nm. In some embodiments, the first pedestal 205 has a height 216 of about 300 nm. In some embodiments, the first pedestal 205 comprises a magnetic material having a saturation magnetization lower than the saturation magnetization of the main pole 202. In some embodiments, the first pedestal 205 has a saturation magnetization of about 10 kG to about 22 kG. In some embodiments, the first pedestal 205 has a saturation magnetization of about 19 kG.

[0060] In some embodiments, the first return pole 203 comprises a magnetic reading shield (MLS) 209 positioned adjacent to the air bearing surface 211. In some embodiments, the magnetic reading shield 209 has a thickness 214 of about 0.1 μm to about 1 μm, with a nominal value of about 0.5 μm. In some embodiments, the magnetic reading shield 209 has a height 215 of about 0.5 μm to about 2.0 μm. In some embodiments, the magnetic reading shield 209 has a height 215 of about 0.8 μm.

[0061] In some embodiments, a first return pole 203 may be operably connected to a main pole 202 by a first connector 204. In some embodiments, the first connector 204 includes a magnetic material having a saturation magnetization lower than the saturation magnetization of the main pole 202. In some embodiments, the first connector 204 has a saturation magnetization of about 10 kG to about 22 kG. In some embodiments, the first connector 204 has a saturation magnetization of about 19 kG.

[0062] In some embodiments, the main pole 202 further comprises an upper yoke 210 configured to help control the concentration of magnetic flux on the back of the main pole 202. In some embodiments, the upper yoke 210 is recessed from the air bearing surface 211. In some embodiments, the upper yoke 210 contains a magnetic material having a saturation magnetization lower than the saturation magnetization of the main pole 202. In some embodiments, the upper yoke 210 has a saturation magnetization of about 10 kG to about 22 kG. In some embodiments, the upper yoke 210 has a saturation magnetization of about 19 kG. In some embodiments, a first return pole 203 is operably connected to the upper yoke 210 by a first connector 204.

[0063] In some embodiments, the writer head further comprises at least one coil 217 configured to conduct current and provide a magnetomotive force to the writer head. In some embodiments, the at least one coil 217 is positioned between the optical component 201 and the first return pole 203. The at least one coil may comprise any number of loops effective in providing a magnetomotive force to the writer head. In some embodiments, the at least one coil 217 comprises loops numbered 1 to 6.

[0064] In some embodiments, the writer head includes a second return pole 206 configured to allow the magnetic flux from the main pole 202 to complete a loop. In some embodiments, the second return pole 206 extends to an air bearing surface 211. The distance between the main pole 202 and the second return pole 206 can be selected to maximize the magnetic field at the recording point on the recording medium. In some embodiments, the second return pole 206 is located on the same side as the optical component 201 of the main pole 202. In such embodiments, the distance between the second return pole 206 and the main pole 202 is limited by the optical component 201. In some embodiments, the distance between the main pole 202 and the second return pole 206 is about 100 nm to about 2,000 nm. In some embodiments, the distance between the main pole 202 and the second return pole 206 is about 800 nm.

[0065] The second return pole 206 may have any thickness that is effective in allowing the magnetic flux from the main pole 202 to complete the loop. In some embodiments, the thickness of the second return pole 206 is limited by the position of the optical component 201. In some embodiments, the second return pole 206 has a thickness of about 100 nm to about 1,500 nm. In some embodiments, the second return pole 206 has a thickness of about 500 nm. In some embodiments, the second return pole 206 comprises a magnetic material having a saturation magnetization lower than the saturation magnetization of the main pole 202. In some embodiments, the second return pole 206 has a saturation magnetization of about 10 kG to about 22 kG. In some embodiments, the second return pole 206 has a saturation magnetization of about 19 kG.

[0066] In some embodiments, the second return pole 206 comprises a second pedestal 208 configured to determine the distance between the second return pole 206 and the main pole 202. In some embodiments, the second pedestal 208 is positioned adjacent to the air bearing surface 211. In some embodiments, the second pedestal 208 has a thickness of about 1.5 μm to about 2.5 μm. In some embodiments, the second pedestal 208 has a thickness of about 2 μm. In some embodiments, the second pedestal 208 has a height of about 200 nm to about 1,000 nm. In some embodiments, the second pedestal 208 has a height of about 500 nm. In some embodiments, the second pedestal 208 comprises a magnetic material having a saturation magnetization lower than the saturation magnetization of the main pole 202. In some embodiments, the second pedestal 208 has a saturation magnetization of about 10 kG to about 22 kG. In some embodiments, the second pedestal 208 has a saturation magnetization of about 19 kG.

[0067] In some embodiments, the second return pole 206 comprises a magnetic reading shield (MLS) 209 positioned adjacent to the air bearing surface 211. In some embodiments, the magnetic reading shield 209 has a thickness of about 0.1 μm to about 0.8 μm. In some embodiments, the magnetic reading shield 209 has a thickness of about 0.5 μm. In some embodiments, the magnetic reading shield 209 has a height of about 0.5 μm to about 1.0 μm. In some embodiments, the magnetic reading shield 209 has a height of about 0.8 μm.

[0068] In some embodiments, a second return pole 206 may be operably connected to the main pole 202 by a second connector 207. In some embodiments, the second connector 207 includes a magnetic material having a saturation magnetization lower than the saturation magnetization of the main pole 202. In some embodiments, the second connector 207 has a saturation magnetization of about 10 kG to about 22 kG. In some embodiments, the second connector 207 has a saturation magnetization of about 19 kG.

[0069] In such embodiments, where the writer head includes a first return pole 203 and a second return pole 206, the writer head may include at least one coil 217 positioned between the first return pole 203 and the main pole 202, and at least one coil 217 positioned between the second return pole 206 and the main pole 202. In some embodiments, the total number of loops between the first return pole 203 and the main pole 202, and between the second return pole 206 and the main pole 202, is the same. In some embodiments, the writer head has a total of 1 to 6 loops.

[0070] method Methods for manufacturing the aforementioned optical components for a HAMR writer head can be employed.

[0071] A method for manufacturing an optical component for a HAMR writer head comprises providing a substrate, depositing a triangular layer on the surface of the substrate, and depositing each subsequent layer of the optical component. Each layer may be deposited by any method known to those skilled in the art. In some embodiments, the method includes depositing each layer by one of sputter deposition, physical vapor deposition, chemical vapor deposition, plating, or electron beam deposition. Each layer may be deposited to a thickness greater than or equal to a desired thickness of the corresponding layer.

[0072] The method may further include surface treatment of each layer before depositing the next layer. In some embodiments, the surface of each layer is treated to achieve a desired thickness and shape. In some embodiments, the surface treatment includes etching, polishing, milling, laser ablation, or one or more of the above. In some embodiments, the surface treatment includes creating a smooth surface. In some embodiments, one or more surfaces of the layers are treated to create a tapered section with a tapered edge. In some embodiments, the tapered edge has an angle of about 20 to about 70 degrees. In some embodiments, the tapered edge has an angle of about 45 degrees. In some embodiments, the surface may be treated to control the position of the layer relative to the air bearing surface.

[0073] The method may further include operably connecting the principal poles to the optical component. In some embodiments, the principal poles are deposited on the optical component. The principal poles may be deposited by any method known to those skilled in the art. In some embodiments, the principal poles are deposited by one of sputter deposition, physical vapor deposition, chemical vapor deposition, plating, or electron beam deposition. The principal poles may be deposited to a thickness greater than or equal to the desired thickness of the final product. The principal poles may be deposited such that the surface of the poles in contact with the optical component has a tapered edge. In some embodiments, the tapered edge has an angle of about 20 to about 70 degrees. In some embodiments, the tapered edge has an angle of about 45 degrees.

[0074] In some embodiments, the method further includes surface treatment of the surface of the principal magnetic pole opposite the optical component to create a second tapered rim. In some embodiments, the second tapered rim may have an angle of about 20 to about 70 degrees. In some embodiments, the second tapered rim has an angle of about 45 degrees. In some embodiments, the method further includes surface treatment of the surface of the principal magnetic pole opposite the optical component to create a flat surface. [Examples]

[0075] Example 1: Magnetic field test The magnetic and thermal properties of HAMR writer heads as disclosed herein were compared with existing HAMR writer head designs. These properties were compared using modeling and simulation results for the magnetic field at the recording location, the magnetic field angle at the recording location, and the temperature of the main magnetic pole during recording. Graph representations of the test results are provided in Figures 3 to 5. HAMR writer heads with tapered main magnetic poles had a 60% higher magnetic field during recording and a 40% lower magnetic field angle during recording compared to conventional HAMR writer heads. These improvements indicate that tapered main magnetic poles result in a significant increase in the surface density capacity of the HAMR. Furthermore, HAMR writer heads with tapered main magnetic poles had a 30% lower temperature of the main magnetic pole during recording compared to conventional HAMR writer heads. This indicates that HAMR writer heads with tapered main magnetic poles have a more reliable and accurate magnetic field than conventional HAMR writer heads.

[0076] As used herein, the term "about" when preceding a number means a range of ±10% of that number. For example, "about 50" means 45 to 55, and "about 25,000" means 22,500 to 27,500. However, this does not apply if otherwise indicated in the context of this disclosure or if such interpretation is inconsistent.

[0077] This disclosure is not limited to the specific embodiments described herein, which are intended to illustrate various aspects. As will be apparent to those skilled in the art, many modifications and changes can be made without departing from the idea and scope. Functionally equivalent methods and apparatus included within the scope of this disclosure, as well as those enumerated herein, will be apparent to those skilled in the art from this specification. Such modifications and changes are intended to be included within the scope of the appended claims. This disclosure is limited only by the language of the appended claims and the full extent of the equivalents that such claims may enjoy. Furthermore, this disclosure is not limited to specific methods, reagents, compounds, compositions or biological systems, which can, of course, be modified. It should also be understood that the terms used herein are merely descriptive of specific embodiments and are not intended to be limiting.

[0078] In this document, a singular "a," "an," and "the" are considered to include the plural unless otherwise specified in the context. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art. Nothing in this disclosure should be construed as acknowledging that the embodiments described herein do not have any retroactive rights to such disclosures due to prior inventions. In this document, "comprising" means "including, but not limited to."

[0079] Various compositions, methods, and apparatuses are described as “comprising” (meaning “including, but not limited to) various components or processes. However, such compositions, methods, and apparatuses may also “consist essentially of” or “consist of” these components and processes, and such terms should be interpreted as defining a substantially closed set of components.

[0080] In this specification, a person skilled in the art can appropriately substitute plural for singular and singular, depending on the context and application, for the use of substantially all singular and plural terms. For clarity, various singular / plural substitutions may also be explicitly listed herein.

[0081] Those skilled in the art will understand that the terms used herein, particularly those used in the appended claims (e.g., the claim text), are generally intended to be "open" terms (for example, the term "including" should be interpreted as "including, but not limited to," the term "having" should be interpreted as "having at least," and the term "includes" should be interpreted as "including, but not limited to"). Furthermore, if a specific number of constituent elements is intended to be included in a claim, that intention is explicitly stated in the claim, and those skilled in the art will understand that such intention does not exist unless it is explicitly stated. For example, to aid understanding, the following appended claims may use "at least one" or "one or more" as constituent elements of a claim. However, the use of such expressions should not be interpreted as meaning that, when a constituent element of a claim is included by the indefinite article "a" or "an," the claim containing that constituent element is limited to embodiments containing only one of that constituent element. The same applies even if one or more "one or more," at least one "at least one," or the indefinite articles "a" or "an" are used in the same claim (for example, "a" and "an" should be interpreted as meaning "at least one" or "one or more"). The same applies to the definite articles used to include the constituent elements of a claim. Furthermore, even if a specific number of constituent elements of a claim is explicitly stated, a person skilled in the art will recognize that the statement should be interpreted as meaning at least that number (for example, if it is simply stated as "two constituent elements" without other modifiers, it means at least two, i.e., two or more constituent elements).Furthermore, when expressions similar to "at least one of A, B, and C" are used, the construction is generally intended to have the meaning understood by those skilled in the art from its conventional expression (for example, "a system having at least one of A, B, and C" includes, but is not limited to, a system having only A, a system having only B, a system having only C, a system having A and B, a system having A and C, a system having B and C, and a system having all of A, B, and C). Similarly, when expressions similar to "at least one of A, B, or C" are used, they are generally intended to have the conventional meaning understood by those skilled in the art (for example, "a system having at least one of A, B, or C" includes, but is not limited to, a system having only A, only B, only C, A and B, A and C, B and C, and a system having all of A, B, and C). Furthermore, a person skilled in the art will understand that virtually any disjunctive phrase presenting two or more alternative terms in this specification, claims, or drawings should be understood to encompass the possibility of including only one of the terms, either one, or both. For example, the phrase "A or B" should be understood to encompass the possibility of including "A only," "B only," or "A and B."

[0082] Furthermore, even if the features or aspects of the present disclosure are described in the form of Markush groups, a person skilled in the art will recognize that the present disclosure describes any individual component or subgroup of such Markush groups.

[0083] As will be understood by those skilled in the art, for purposes such as satisfying disclosure requirements, all numerical ranges disclosed herein also encompass all possible subranges of such ranges and combinations thereof. Any listed range can be readily understood as sufficiently describing and enabling that the range is divisible into at least equal halves, thirds, quarters, fifths, tenths, etc., etc., of which the range is divisible into lower thirds, middle thirds, upper thirds, etc., as an example without limitation. Also, as will be understood by those skilled in the art, all expressions such as "up to" and "at least" include the numerical value itself and refer to a range that is divisible into subranges as described above. Finally, as will be understood by those skilled in the art, a range includes each individual numerical value within that range. Thus, for example, a group having 1 to 3 cells means a group having 1, 2, or 3 cells. Similarly, a group having 1 to 5 cells means a group having 1, 2, 3, 4, or 5 cells.

Claims

1. A writer head for a heat-assisted magnetic recording (HAMR) device, An optical component comprising a triangular layer having a tapered edge and a waveguide (WG) layer disposed adjacent to the triangular layer, wherein the WG layer comprises a flat section and a tapered section, the tapered section includes a tapered angle and is in contact with the tapered edge of the triangular layer, A cladding layer is located adjacent to the WG layer, A near-field transducer (NFT) layer is positioned adjacent to the cladding layer and includes a tapered section with a taper angle, A heatsink layer is positioned adjacent to the NFT layer, A peg layer is positioned adjacent to the heat sink layer and includes an insulator and a tapered section including a tapered angle. Optical components including, A magnetic component including a principal magnetic pole, wherein the principal magnetic pole has a first tapered section including a taper angle and a principal magnetic pole section substantially parallel to a flat section of the WG layer, and the principal magnetic pole has a saturation magnetization of about 24 kG or more. A writer's head equipped with this feature.

2. In the writer head described in claim 1, A writer head with a taper angle of approximately 20 to 70 degrees.

3. In the writer head described in claim 1, A writer head with a triangular layer containing a waveguide cutoff layer with ruthenium.

4. In the writer head described in claim 1, A lighter head in which a triangular layer contains one or more of alumina or silica.

5. In the writer head described in claim 1, The NFT layer includes a first NFT layer containing a first metal and a second NFT layer containing a transition metal. The first NFT layer contains one or more of gold, silver, copper, their alloys, graphene, and metal oxides. A writer head in which the second NFT layer includes one of Rh or Ir.

6. In the writer head described in claim 1, A lighter head in which the heat sink layer contains one or more of gold, ruthenium, aluminum nitride, or silicon carbide.

7. In the writer head described in claim 1, A writer head in which the optical components further include a first oxide layer disposed between an NFT layer and a heat sink layer.

8. In the writer head described in claim 1, A writer head in which the tapered section of the main magnetic pole includes a taper angle.

9. In the writer head described in claim 1, A writer head in which the first tapered section of the main magnetic pole has a thickness of approximately 20 nm to approximately 100 nm.

10. In the writer head described in claim 1, A writer head in which the ratio of the thickness of the first tapered section of the main magnetic pole to the average particle size of the recording medium is approximately 1.4 to approximately 14.

11. In the writer head described in claim 1, A writer head in which the main magnetic pole section has a thickness of approximately 200 nm to 600 nm.

12. In the writer head described in claim 1, A writer head in which the ratio of the thickness of the main magnetic pole section of the main magnetic pole to the average particle size of the recording medium is approximately 29 to approximately 86.

13. In the writer head described in claim 1, A writer head in which the main magnetic pole includes a second tapered section having the same taper angle as the first tapered section.

14. In the writer head according to claim 13, A writer head in which the second tapered section of the main magnetic pole has a thickness of approximately 20 nm to approximately 100 nm.

15. In the writer head according to claim 13, A writer head in which the ratio of the thickness of the second tapered section of the main magnetic pole to the average particle size of the recording medium is approximately 1.4 to approximately 14.

16. In the writer head described in claim 1, A writer head, further comprising an optical component, a laser diode configured to generate a light beam.

17. In the writer head described in claim 1, A writer head in which the magnetic component includes a first return pole operably connected to a main magnetic pole by a first connector and located on the side of the main magnetic pole opposite the optical component.

18. In the writer head according to claim 17, A writer head in which the distance between the first return pole and the principal pole is approximately 50 nm to approximately 1,000 nm.

19. In the writer head according to claim 17, A writer head in which the first return magnetic pole has a thickness of approximately 500 nm to approximately 1,500 nm.

20. In the writer head according to claim 17, A writer head comprising a first return pole, which includes a first pedestal having a thickness of approximately 1.5 μm to approximately 2.5 μm and a height of approximately 200 nm to approximately 1,000 nm.

21. In the writer head according to claim 17, A writer head further comprising a first magnetic reading shield (MLS) having a thickness of approximately 100 nm to approximately 1,000 nm and a height of approximately 500 nm to approximately 2,000 nm, wherein the first return pole is a first magnetic reading shield (MLS).

22. In the writer head according to claim 17, A writer head in which the magnetic components include a first yoke positioned between a first connector and a main magnetic pole.

23. In the writer head according to claim 17, A writer head in which the magnetic components include a second return pole operably connected to a main pole by a second connector and positioned on the side of the main pole opposite the first return pole.

24. In the writer head according to claim 23, A writer head in which the distance between the second return pole and the main pole is approximately 100 nm to approximately 2,000 nm.

25. In the writer head according to claim 23, The second return magnetic pole has a thickness of approximately 100 nm to 1,500 nm and is located in the writer head.

26. In the writer head according to claim 23, A writer head comprising a second return pole, which includes a second pedestal having a thickness of approximately 1.5 μm to approximately 2.5 μm and a height of approximately 200 nm to approximately 1,000 nm.

27. In the writer head according to claim 23, A writer head further comprising a second magnetic reading shield (MLS) having a second return pole having a thickness of approximately 100 nm to approximately 800 nm and a height of approximately 500 nm to approximately 1,000 nm.

28. In the writer head according to claim 17, A writer head in which the magnetic components further include a coil containing 0 to 6 loops, the coil being positioned between a first return pole and a principal pole.

29. In the writer head according to claim 23, A writer head in which the magnetic components further include a first coil and a second coil, the combined first and second coils comprising 0 to 6 loops, the first coil positioned between a first return pole and a main pole, the second coil positioned between a second return pole and a main pole, and the first and second coils comprising the same number of loops.

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