VCSEL array for hamr

Abstract

The invention is entitled "VCSEL array for HAMR." The present disclosure relates to the pre-processing of a magnetic recording head for a magnetic media drive. For a heat-assisted magnetic recording (HAMR) head, an optical source provides the heat necessary for the drive operation. A vertical cavity surface emitting laser (VCSEL) is mounted to the top surface of the slider. A plurality of laser beams are emitted from the bottom surface of the VCSEL and are directed to a corresponding number of waveguide structures within the HAMR head. The waveguide structures feed into a multimode interference (MMI) device which then directs the laser light into a single waveguide to be focused on a near-field transducer (NFT). The VCSEL laser is phase coherent and does not have mode hopping.

Description

[0001] This application is a divisional application of Chinese Patent Application No. 202110271041.4, filed March 11, 2021, entitled: “VCSEL ARRAY FOR HAMR.” BACKGROUND TECHNICAL FIELD

[0003] Embodiments of the present disclosure generally relate to a magnetic recording head for a magnetic media drive.

[0004] Description of the Related Art

[0005] At the heart of the functionality and capability of a computer is the storage of data and writing of data to a data storage device such as a magnetic media drive (e.g., a hard disk drive (HDD)). The amount of data processed by a computer is rapidly increasing. Higher recording densities of magnetic recording media are needed to increase the functionality and capability of a computer.

[0006] To achieve higher recording densities of magnetic recording media (such as recording densities exceeding 2 terabit / inch 2 of track width and pitch, and thus corresponding magnetic recording bits encoded in each write track, is to reduce the surface area of the main pole of the magnetic recording write head at the media-facing surface of the recording media. As the main pole becomes smaller and smaller, the recording field also becomes smaller and smaller, thereby limiting the effectiveness of the magnetic recording write head.

[0007] Heat-assisted magnetic recording (HAMR) and microwave-assisted magnetic recording (MAMR) are two energy-assisted recording techniques that improve the recording density of magnetic recording media. In HAMR, a laser source is located next to or near the write element to generate heat, such as a laser source that excites a near-field transducer (NFT) to generate heat at the write location of the magnetic recording media.

[0008] HAMR typically utilizes an edge-emitting laser diode (EELD) as the light source. There are multiple issues with EELD, such as: the need to install a sub-mount to the slider, which increases cost; mode jumping, which abruptly changes recording power and reduces HAMR HDD capacity; a small diameter output beam that makes there is little alignment tolerance; a large intensity optical mode at the facet, which reduces reliability; the need for burn-in during manufacturing, which increases cost; and a high profile on the slider, which increases the spacing between disks and disks.

[0009] Accordingly, there is a need in the art for improved HAMR magnetic media drives. SUMMARY

[0010] The present disclosure relates to the pre-processing of a magnetic recording head for a magnetic media drive. For a heat assisted magnetic recording (HAMR) head, a light source provides the necessary heat for the drive operation. A vertical cavity surface emitting laser (VCSEL) is mounted to a top surface of a slider. A plurality of laser beams are emitted from a bottom surface of the VCSEL and are directed to a corresponding number of waveguide structures within the HAMR head. The waveguide structures feed into a multimode interference (MMI) device which then directs the laser light into a single waveguide to be focused on a near field transducer (NFT). The VCSEL laser is phase coherent and does not have mode hopping.

[0011] In one embodiment, a vertical cavity surface emitting laser (VCSEL) device includes a chip for mounting on a slider, wherein the chip has a first surface for facing the slider, and a plurality of laser holes disposed in the first surface, wherein the plurality of laser holes are spaced apart at a pitch of between 2 microns and 10 microns, wherein the VCSEL device is capable of emitting a plurality of channels of laser light corresponding to the plurality of laser holes, and wherein the plurality of channels of laser light operate at the same frequency, and wherein the plurality of laser holes are arranged in a straight line.

[0012] In another embodiment, a magnetic recording head assembly includes a front shield, a main pole, a near field transducer (NFT) coupled between the front shield and the main pole, a waveguide structure coupled to the NFT, wherein the waveguide structure includes a first waveguide coupled to the NFT, a multimode interference (MMI) device coupled to the first waveguide at a first end, and a plurality of second waveguides coupled to a second end of the MMI device opposite the first end, wherein the plurality of second waveguides extend from the MMI device to a top surface of the head assembly, wherein the top surface of the head assembly is opposite a media facing surface, and a vertical cavity surface emitting laser (VCSEL) device coupled to the top surface.

[0013] In another embodiment, a magnetic media drive includes a magnetic recording head, wherein the magnetic recording head includes a near field transducer (NFT) at a media facing surface (MFS), a waveguide structure extending between the NFT and a first surface opposite the MFS, and a vertical cavity surface emitting laser (VCSEL) device coupled to the first surface, wherein the VCSEL includes a second surface facing the first surface, wherein the VCSEL is capable of emitting a plurality of channels of laser light through the second surface, and a magnetic media facing the MFS. BRIEF DESCRIPTION OF DRAWINGS

[0014] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, can be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure can admit to other equally effective embodiments.

[0015] Figure 1 is a schematic diagram of certain embodiments of a magnetic media drive including a HAMR magnetic write head.

[0016] Figure 2 is a schematic diagram of certain embodiments of a cross-sectional side view of a disk-oriented HAMR write head.

[0017] Figure 3A and Figure 3B is a schematic diagram of a slider having a VCSEL mounted thereon according to one embodiment.

[0018] Figures 4A-4C is a schematic diagram of a VCSEL according to one embodiment.

[0019] Figure 5 is a schematic diagram of a waveguide structure of a HAMR head according to one embodiment.

[0020] To facilitate the understanding of this description, like reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one embodiment can be advantageously used in other embodiments without specific recitation. DETAILED DESCRIPTION

[0021] Hereinafter, reference is made to embodiments of the present disclosure. However, it should be understood that the present disclosure is not limited to the particularly described embodiments. Rather, any combination of the following features and elements, whether related to different embodiments or not, is contemplated to implement and practice the present disclosure. Additionally, while the embodiments of the present disclosure can achieve advantages over other possible solutions and / or over the prior art, whether or not a particular advantage is achieved by a given embodiment is not limiting of this disclosure. Thus, the following aspects, features, embodiments and advantages are merely illustrative and are not considered elements or limitations of the appended claims except where explicitly recited in a claim. Likewise, reference to "the disclosure" should not be interpreted as an identification of any specific invention or matter covered by the patent claims or disclosure, and should not be interpreted as a generalization of any such invention or matter, unless explicitly recited in a claim.

[0022] The present disclosure relates to the pre-processing of a magnetic recording head for a magnetic media drive. A light source provides the necessary heat for the operation of a heat-assisted magnetic recording (HAMR) head. A vertical cavity surface emitting laser (VCSEL) is mounted to the top surface of the slider. A plurality of laser beams are emitted from the bottom surface of the VCSEL and are directed to a corresponding number of waveguide structures within the HAMR head. The waveguide structures feed into a multimode interference (MMI) device which then directs the laser light into a single waveguide to be focused on a near-field transducer (NFT). The VCSEL laser is phase coherent and does not have mode hopping.

[0023] Figure 1 is a schematic diagram of certain embodiments of a magnetic media drive including a HAMR magnetic write head. Such a magnetic media drive can be a single drive / device or include multiple drives / devices. For ease of illustration, a single disk drive 100 is shown in accordance with one embodiment. The disk drive 100 includes at least one rotatable magnetic recording medium 112 (commonly referred to as a disk 112) supported on a spindle 114 and rotated by a drive motor 118. The magnetic recording on each disk 112 is in the form of any suitable pattern of data tracks, such as a ring pattern of concentric data tracks (not shown) on the disk 112.

[0024] At least one slider 113 is positioned near the disk 112. Each slider 113 supports a head assembly 121 that includes one or more read heads and one or more write heads, such as a HAMR write head. As the disk 112 rotates, the slider 113 moves radially in and out over the disk surface 122 so that the head assembly 121 can access different tracks of the disk 112 to write desired data. Each slider 113 is attached to an actuator arm 119 by a suspension 115. The suspension 115 provides a slight spring force that biases the slider 113 toward the disk surface 122. Each actuator arm 119 is attached to an actuator 127. The actuator 127 shown can be a voice coil motor (VCM). The VCM includes a coil that is able to move within a fixed magnetic field, the direction and speed of the coil’s movement being controlled by motor current signals supplied by a control unit 129. Figure 1

[0025] During operation of the disk drive 100, the rotation of the disk 112 creates an air bearing between the slider 113 and the disk surface 122 that exerts an upward force, or lift, on the slider 113. Thus, during normal operation, the air bearing counterbalances the slight spring force of the suspension 115 and supports the slider 113 a small, substantially constant distance away and slightly above the disk surface 122.

[0026] ​Various components of the disk drive 100 are controlled in operation by control signals generated by the control unit 129, such as access control signals and internal clock signals. Generally, the control unit 129 includes logic control circuitry, storage, and a microprocessor. The control unit 129 generates control signals to control various system operations, such as drive motor control signals on line 123 and head position and tracking control signals on line 128. The control signals on line 128 provide a desired current profile to optimally move and position the slider 113 to a desired data track on the disk 112. Write and read signals are communicated to and from the head assembly 121 through the recording channel 125. Figure 1 Certain embodiments of the magnetic media drive can also include multiple media or disks, multiple actuators, and / or multiple sliders.

[0027] Figure 2 is a schematic diagram of certain embodiments of a cross-sectional side view of a HAMR write head 230 facing the disk 112. The HAMR write head 230 can correspond to a portion of the read / write head assembly 121 described in Figure 1 or to a recording head for other magnetic media drives. The HAMR write head 230 includes a media-facing surface (MFS), such as an air bearing surface (ABS) or a gas bearing surface (GBS), that faces the disk 112. As shown in Figure 2 the disk 112 and the HAMR write head 230 are moved relative to one another in the direction indicated by arrow 282 (directions need to be changed).

[0028] The HAMR write head 230 includes a main pole 236 disposed between a front return pole 234 and a back return pole 238. The main pole 236 can include a main pole tip 237 at the MFS. The main pole tip 237 can or can not include a front and / or back ramp. A coil 260 around the main pole 236 excites the main pole tip 237 to generate a write magnetic field for affecting the magnetic media of the rotatable disk 112. The coil 260 can be a spiral structure or one or more sets of flat structures. The front and / or back shields 234 and 238 can act as return poles for the main pole 236.

[0029] The disk 112 is positioned adjacent to or below the HAMR write head 230. The magnetic field generated by the current in the coil 260 is used to control the magnetization direction of bits in the disk 112.

[0030] HAMR write head 230 includes a structure for heating magnetic disk 112 near the location of a magnetic write field applied to the disk 112 at main pole tip 237. Waveguide 242 is positioned between main pole 236 and front shield 234. Waveguide 242 can include a core layer and a cladding layer surrounding the core layer. Waveguide 242 conducts light from a light source 278 of electromagnetic radiation, which can be, for example, ultraviolet, infrared, or visible light. Light source 278 can be, for example, a laser diode or other suitable laser source for directing a beam of light into waveguide 242. Various techniques known for coupling light sources 278 into waveguides 242 can be used. For example, light source 278 can work in conjunction with an optical fiber and external optics for directing the beam of light into waveguide 242. Alternatively, light source 278 can be mounted on waveguide 242 and the beam of light can be directly coupled into waveguide 242 without the need for external optics. Once the beam of light is coupled into waveguide 242, the light propagates through the waveguide and heats a portion of the media as the media is moved relative to HAMR write head 230 as indicated by arrow 282.

[0031] HAMR write head 230 can include a near-field transducer (NFT) 284 to concentrate heat near the end of waveguide 242. NFT 284 is positioned in or adjacent to waveguide 242 near or at the MFS. Light from waveguide 242 is absorbed by NFT 284 and excites a surface plasmon that travels along the outside of NFT 284 toward the MFS, thereby concentrating the charge at the tip of NFT 284, which in turn capacitively couples to the disk and heats a precise area of disk 112 through Joule heating. One possible NFT 284 for a HAMR write head is a lollipop design with a disk portion and a peg extending between the disk and the MFS. NFT 284 can be positioned immediately adjacent to main pole 236. NFT 284 is relatively thermally isolated and absorbs a large portion of the laser power when it is resonating.

[0032] Figure 3A and Figure 3B is a schematic view of slider 302 with a VCSEL 304 mounted thereon, in accordance with one embodiment. As Figure 3BAs shown, VCSEL 304 is mounted to slider 302 at a first position via first contact 308a and second contact 308b. In one embodiment, VCSEL 304 is mounted on top of slider 302; this differs from edge-emitting laser diodes (EELDs), which typically require mounting to a sub-mount first due to the difficulty of directly bonding the edge-emitting faceted plane of the laser to the top of the slider. VCSEL 304 can have a minimal design structure, allowing its size to reduce the overall size of the HAMR write head. VCSEL 304 includes a mesa 306 on its bottom surface facing slider 302, with the mesa 306 positioned between VCSEL 304 and slider 302. Figure 3B In the diagram, VCSEL 304 is shown in dashed lines to provide better visibility of the electrode 321 on the top surface of slider 302. Electrode 321 provides electrical connection to the electrode of VCSEL 304 via a conductive soldering material. Electrode 321, the soldering material, and the electrode of VCSEL 304 together form a first contact 308a and a second contact 308b. Electrode 321 extends above slider 302 at a distance between approximately 1 micrometer and approximately 3 micrometers.

[0033] VCSEL 304 is capable of emitting multi-channel lasers corresponding to multiple laser apertures on the mesa 306, wherein each of the multi-channel lasers corresponds to the multiple laser apertures on the mesa 306 (e.g., ...). Figure 4C (As shown) Alignment. Furthermore, slider 302 includes a plurality of speckle transducers 314a-314n that match the position and number of input lasers emitted by VCSEL 304. The speckle transducers 314a-314n extend from the top surface of slider 302 facing VCSEL 304. Mesa 306 is spaced from the top surface of slider 302 at a first distance 318 of approximately 1 μm to approximately 20 μm. Mesa 306 includes a plurality of laser apertures, such as approximately 2 to approximately 16 laser apertures. The previously listed values ​​are not intended to be limiting, but rather to provide examples of embodiments. The mesa is part of the VCSEL 304 chip, and the apertures are located on the surface of mesa 306. Mesa 306 is an optional textured structure on the surface of VCSEL 304.

[0034] The number of the above-described lasers that the VCSEL 304 is capable of emitting matches the number of laser holes of the mesa 306 and the number of mode converters 314a-314n. Each lane of laser and thus each mode converter 314a-314n is spaced apart by a second distance. The second distance between each of the mode converters 314a-314n is about 2 pm to about 10 pm. Further, each lane of the plurality of lasers emitted by the VCSEL 304 operates at the same frequency and is phase coherent. For example, adjacent holes can be in phase or out of phase with each other. Each lane of the plurality of lasers emitted by the VCSEL 304 has a power level of between about 1 mW to about 10 mW. The previously listed values are not intended to be limiting, but rather provide examples of embodiments. The plurality of lasers each have an active area (e.g., an area where the laser excites electrons). The active areas are spaced close enough to enable coupling and phase coherence to occur.

[0035] The slider 302 includes a plurality of bond pad studs 312a-312n (such as about 2 bond pad studs to about 32 bond pad studs). The bond pad studs 312a-312n have a first width 320 of about 25 pm, with a spacing between adjacent bond pad studs 312a-312n of about 32 pm. The previously listed values are not intended to be limiting, but rather provide examples of embodiments. The plurality of mode converters 314a-314n are disposed at locations between adjacent bond pad studs 312a-312n. In Figure 3A In the illustrated embodiment, the mode converters 314a-314n are disposed between bond pad studs 312c and 312d. Thus, in one example embodiment, all of the mode converters 314a-314n need to fit within a linear distance of about 32 pm. Further, the plurality of lanes of lasers and thus the plurality of mode converters 314a-314n are linearly arranged. Each mode converter 314a-314n is spaced apart from adjacent mode converters 314a-314n by about 2 pm to about 10 pm.

[0036] The plurality of mode converters 314a-314n feed into a multimode interference (MMI) device 310 disposed within the slider 302. The MMI device 310 merges the lasers fed from the output of the plurality of mode converters 314a-314n at a first end and emits a single lane of laser light through a single output waveguide 316. The single waveguide 316 emits laser light from the MMI device 310 that includes the combined power from the plurality of input lanes of laser light from the plurality of mode converters 314a-314n received by the MMI device 310. A single output mode is needed to properly concentrate the optical power and couple to the NFT. Proper operation of the MMI generally requires stable phase coherence between the inputs.

[0037] Figure 4A This is a schematic diagram of the side view of VCSEL 400. Figure 4B This is a schematic diagram of the top view of VCSEL 400, and Figure 4C This is a schematic bottom view of a VCSEL 400 according to various embodiments. The side surface 402 of the VCSEL 400 has a height of approximately 75 μm to approximately 150 μm and a length of approximately 100 μm to approximately 250 μm. The top surface 404 and bottom surface 406 of the VCSEL 400 include the same dimensions. The dimensions of the top surface 404 and bottom surface 406 include a width of approximately 150 μm and a length of approximately 150 μm, wherein the lengths of the top surface 404, bottom surface 406, and side surface 402 are equal. Figure 4B As shown, the VCSEL 400 may have multiple electrodes 411 on its top surface 404, and these electrodes can be used to energize the VCSEL during active alignment prior to bonding.

[0038] exist Figure 4C In the process, multiple laser holes 408a-408n are disposed on the bottom surface 406 of the VCSEL 400. The number of laser holes 408a-408n is related to the modulus converter of the slider (such as...). Figure 3A The number of laser apertures 408a-408n is matched. Each laser aperture 408a-408n is spaced apart from its adjacent laser aperture 408a-408n by a distance 412 of approximately 2 μm to approximately 10 μm. Furthermore, the laser apertures 408a-408n are aligned about a centerline, and each of the plurality of laser apertures 408a-408n is aligned with its corresponding input laser. In addition to being aligned with each input laser, the laser apertures 408a-408n are also aligned with corresponding laser apertures on the stage (such as the laser apertures on stage 306 in Figure 3).

[0039] like Figure 4CAs shown, the bottom surface 406 of the VCSEL 400 has a plurality of electrodes 410 thereon to function as anodes and cathodes and mate with the electrodes 321 of the slider 302 via a solder material. The electrodes 410 extend from the bottom surface 406 of the VCSEL 400 toward the slider at a distance of between about 1 micron and about 3 microns. Thus, in one embodiment, the gap between the VCSEL 400 and the slider 302 is between about 2 microns and about 6 microns. Additionally, the VCSEL 400 has a length 428 of between about 100 microns and about 200 microns. The VCSEL 400 also has a length 426 of between about 100 microns and about 200 microns. The holes 408a-408n each have a diameter of between about 1.5 microns and about 8 microns and are on a pitch of 2 microns to 10 microns. The centers of the holes 408a-408n are spaced apart from the side surface 402 by a distance 422 of between about 35 microns and about 50 microns. The centers of the holes 408a-408n are spaced apart from the electrodes 410 by a distance 424 of between about 75 microns and about 90 microns.

[0040] Figure 5 is a schematic of a waveguide structure 500 of a HAMR head according to one embodiment. The slider (such as the slider 302 of FIG. 3) includes the waveguide structure 500, which includes a first mode spot converter 506 extending from an NFT to an MMI device 502. The waveguide structure 500 also includes a plurality of second mode spot converters 504a-504n, such as about 2 second mode spot converters to about 8 second mode spot converters. The number of second mode spot converters 504a-504n matches the number of laser holes 408a-408n of the VCSEL 400 described in Figure 4C the number of laser holes of the mesa 306 described in Figure 3A the number of mode spot converters 314a-314n described in Figure 3A and the number of laser holes of the VCSEL 400 described in

[0041] The plurality of second mode spot converters 504a-504n fit within the pitch between the bond pad studs (such as the bond pad studs 312a-312n) such that the distance between the leftmost second mode spot converter 504a and the rightmost second mode spot converter 504n is less than the pitch of about 32 pm between the bond pad studs. Further, Figure 4C the plurality of laser holes 408a-408n of the VCSEL described in Figure 3A the plurality of laser holes of the mesa 306 described in and the laser light emitted by the plurality of laser holes are each aligned with a corresponding second mode spot converter 504a-504n.

[0042] As described above, the waveguide structure 500 also includes the MMI device 502. The MMI device 502 can be the same as the MMI device 310 of FIG. 3. A first mode spot converter 506 at a first end is coupled to the MMI device 502 at the first end, and the plurality of second mode spot converters 504a-504n at a second end are coupled to the MMI device 502 at a second end opposite the first end. The first mode spot converter 506 is also coupled to an NFT, such as the NFT 284 of FIG. 3, at a second end. Figure 2

[0043] Further, the core width of the second mode spot converters 504a-504n gradually increases from about 150 nm to about 600 nm in a direction toward the MMI device 502. At 150 nm, the spot size matches the large VCSEL mode size of a few microns. At 600 nm, the waveguide mode is only a few hundred nanometers before entering the MMI device 502.

[0044] Using a VCSEL as the light source in HAMR has several significant advantages. Edge emitting laser diodes (EELDs) are currently used and are typically mounted to a sub-mount because it is difficult to directly bond the edge emitting facet of the laser to the top of the slider. The sub-mount is then bonded to the slider. A VCSEL can easily have a bond electrode on the surface emitting facet that mates with a corresponding electrode on the top surface of the slider. These electrodes can be bonded together with laser assisted solder reflow and also serve as the electrical connection to power the laser. By eliminating the need for a sub-mount, the light source cost can be significantly reduced. VCSEL laser facets are manufactured in a wafer level process, which further reduces the cost relative to EELDs. The VCSEL output beam is also larger and more circular than that of an EELD, which increases the alignment tolerance and coupling efficiency to the slider mode spot converter. VCSELs are known to have higher reliability than EELDs due to the larger, less intense optical mode and wafer facet process. Therefore, VCSELs do not need to be aged during manufacturing, which further reduces the cost. The lower overall height due to the shorter VCSEL cavity length than an EELD and because the laser is mounted on the top of the slider allows for a reduced disk to disk spacing, potentially more disks, and higher HDD capacity.

[0045] Further, due to the very short cavity length and one longitudinal mode and DBR mirror selectivity, VCSELs have a mode hop free operation, whereas EELDs are subject to mode hopping. Mode hopping can cause a sudden change in laser power of a few percent (typically 1-2%) during the recording process. The possibility of track width variations and bit shifts must be considered, which reduces the capacity of the HDD.

[0046] ​A major technical problem with VCSELs is the relatively low output power relative to EELDs. Multi-mode VCSELs can have greater output power than single-mode VCSELs, but the waveguides and NFTs used to create hot spots in the disk for HAMR require single-mode operation. Single-mode VCSELs typically have a maximum output power of only about 2 mW, far below the 10-20 mW required for HAMR. The output from multiple individual VCSELs cannot be effectively added together by combining the outputs from multiple individual VCSELs due to de-coherence between the wavefronts. If the active areas of adjacent VCSELs are brought very close together, the wave functions will overlap enough to create coupling and phase coherence between their outputs. With the right VCSEL design and light delivery scheme, these outputs can be combined into a single waveguide with the single-mode power required for the NFTs used for HAMR, which must be 5-10 mW.

[0047] In one embodiment, a vertical cavity surface emitting laser (VCSEL) device includes a chip for mounting on a slider, wherein the chip has a first surface for facing the slider, and a plurality of laser apertures disposed in the first surface, wherein the plurality of laser apertures are spaced apart by a distance of between about 2 microns and about 10 microns, wherein the VCSEL device is capable of emitting a plurality of channels of laser light corresponding to the plurality of laser apertures, wherein the plurality of channels of laser light operate at the same frequency, and wherein the plurality of laser apertures are arranged linearly. The VCSEL device is capable of emitting a plurality of channels of laser light that are phase coherent. The plurality of laser apertures includes 2 to 8 laser apertures. The VCSEL device is capable of emitting a plurality of channels of laser light corresponding to the plurality of laser apertures, and wherein each of the plurality of channels of laser light has a power level of between about 1 mW and about 10 mW. The first surface includes a mesa, and wherein the plurality of laser apertures are disposed in the mesa, wherein the plurality of laser apertures are spaced apart by a distance of between about 2 microns and about 10 microns. The VCSEL device further includes a plurality of electrodes coupled to the first surface. The electrodes extend from the first surface toward the slider by about 10 microns, and more preferably up to 2 microns. A magnetic media drive including the VCSEL device is also disclosed.

[0048] In another embodiment, a magnetic recording head assembly includes: a front shield; a main pole; a near-field transducer (NFT) coupled between the front shield and the main pole; a waveguide structure coupled to the NFT, wherein the waveguide structure includes: a first waveguide coupled to the NFT; a multimode interference (MMI) device coupled to the first waveguide at a first end; and a plurality of second waveguides coupled to a second end opposite the first end of the MMI device, wherein the plurality of second waveguides extend from the MMI device to a top surface of the head assembly, wherein the top surface of the head assembly is opposite a media-facing surface; and a vertical-cavity surface-emitting laser (VCSEL) device coupled to the top surface. The VCSEL has a plurality of laser apertures aligned with the plurality of second waveguides. The plurality of laser apertures are aligned with the plurality of second waveguides in a near-field. The plurality of laser apertures are spaced apart from the top surface by a first distance between about 1 micrometer and about 20 micrometers. The plurality of second waveguides includes 2 to 16 second waveguides. A magnetic media drive including the magnetic recording head assembly is also disclosed.

[0049] In another embodiment, a magnetic media drive includes: a magnetic recording head, wherein the magnetic recording head includes: a near-field transducer (NFT) at a media-facing surface (MFS); a waveguide structure extending between the NFT and a first surface opposite the MFS; and a vertical-cavity surface-emitting laser (VCSEL) device coupled to the first surface, wherein the VCSEL includes a second surface facing the first surface, wherein the VCSEL is capable of emitting a plurality of laser beams through the second surface; and a magnetic media facing the MFS. The second surface is spaced apart from the first surface by between about 1 micrometer and about 20 micrometers. A width of the waveguide structure is less than a width between adjacent electrodes of a slider on which the magnetic recording head is disposed. The VCSEL is capable of emitting the plurality of laser beams that are phase coherent. The waveguide structure includes a multimode interference (MMI) device disposed between the NFT and the first surface. The VCSEL is capable of emitting the plurality of laser beams, and wherein the plurality of laser beams have at least partially overlapping effective areas.

[0050] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure can be devised without departing from the basic scope thereof, and the scope of the present disclosure is determined by the appended claims.

Claims

1. A magnetic recording head assembly, the magnetic recording head assembly comprising: Main pole; The near-field transducer, or NFT, is located near the main electrode. A waveguide structure coupled to the NFT, wherein the waveguide structure comprises: A first waveguide, the first waveguide being coupled to the NFT; A multimode interferometer, or MMI device, is coupled to the first waveguide at its first end; and A plurality of second waveguides coupled to a second end of the MMI device opposite to the first end, wherein the plurality of second waveguides extend from the MMI device to a top surface of the head assembly, wherein the top surface of the head assembly is opposite to the surface facing the medium, wherein the first waveguide emits laser light from the MMI device, the laser light comprising a combined power of a plurality of input laser lights from the plurality of second waveguides; and A vertical cavity surface-emitting laser device, also known as a VCSEL device, is coupled to the top surface.

2. The magnetic recording head assembly of claim 1, wherein the VCSEL device is coupled to the top surface via one or more contacts.

3. The magnetic recording head assembly of claim 2, wherein each of the one or more contacts comprises one or more electrodes.

4. The magnetic recording head assembly of claim 3, wherein the one or more electrodes include a first electrode disposed on the top surface and a second electrode disposed on the VCSEL device.

5. The magnetic recording head assembly of claim 1, wherein the plurality of second waveguides comprises 2 to 16 second waveguides.

6. The magnetic recording head assembly of claim 1, wherein the VCSEL device has a plurality of laser apertures aligned with the plurality of second waveguides.

7. The magnetic recording head assembly of claim 6, wherein the plurality of laser apertures are spaced apart at a distance between about 2 micrometers and about 5 micrometers.

8. The magnetic recording head assembly of claim 1, wherein the plurality of laser apertures are aligned with the plurality of second waveguides in the near field.

9. The magnetic recording head assembly of claim 1, wherein a plurality of laser apertures are spaced apart from the top surface at a first distance between about 1 micrometer and about 20 micrometers.

10. The magnetic recording head assembly of claim 1, further comprising a front cover, wherein the NFT is coupled between the main pole and the front cover.

11. A vertical-cavity surface-emitting laser (VCSEL) device, the device comprising: A chip for mounting on a slider, wherein the chip has a first surface for facing the slider, wherein the first surface has a mesa, wherein the mesa has a plurality of holes, wherein the plurality of holes are spaced apart at a distance between about 1 micrometer and about 20 micrometers; A first electrode is disposed on the first surface, wherein the first electrode is coupled to the first surface; as well as A second electrode is disposed on the first surface, wherein the second electrode is coupled to the first surface, wherein the VCSEL device is capable of emitting multi-channel lasers corresponding to the plurality of holes, wherein the multi-channel lasers operate at the same frequency, and wherein the plurality of holes are arranged in a straight line.

12. The VCSEL device of claim 11, wherein the first electrode is coupled to the first surface via a first welding material.

13. The VCSEL device of claim 12, wherein the first welding material is conductive.

14. The VCSEL device of claim 13, wherein the second electrode is coupled to the first surface via a second welding material.

15. The VCSEL device of claim 14, wherein the second welding material is conductive.

16. The VCSEL device of claim 15, wherein each of the multi-channel lasers has a power level between about 1 mW and about 10 mW.

17. The VCSEL device of claim 11, wherein the apertures are spaced apart at a distance between about 2 micrometers and about 10 micrometers.

18. The VCSEL device of claim 11, wherein the VCSEL device is capable of emitting phase-coherent multi-channel laser.

19. The VCSEL device of claim 11, wherein the plurality of holes comprises 2 to 16 laser holes.

20. The VCSEL device of claim 11, wherein the first electrode and the second electrode extend from the first surface by a maximum of 2 micrometers.

21. The VCSEL device of claim 11, wherein the chip has a height of about 75 μm to about 150 μm and a length of about 100 μm to about 250 μm.

22. A magnetic media driver, the magnetic media driver comprising the VCSEL device according to claim 11.

23. A magnetic media driver, the magnetic media driver comprising: Magnetic recording head, wherein the magnetic recording head includes: The near-field transducer located at the surface facing the medium, i.e., the MFS, is called the NFT; A waveguide structure extending between the NFT and a first surface opposite to the MFS, wherein the waveguide structure includes a multimode interferometer, i.e., an MMI device, disposed between the NFT and the first surface; Multiple laser holes disposed in the first surface; and A vertical cavity surface-emitting laser device, also known as a VCSEL device, is coupled to the first surface, wherein the VCSEL device includes a second surface facing the first surface, and wherein the VCSEL device is capable of emitting multi-channel lasers corresponding to the plurality of laser apertures.

24. The magnetic dielectric driver according to claim 23, wherein the waveguide structure further comprises: A first waveguide, the first waveguide being coupled between the NFT and a first end of the MMI device, and A plurality of second waveguides are coupled to a second end of the MMI device opposite to the first end, wherein the plurality of second waveguides extend from the MMI device to the first surface, wherein the first waveguide emits laser light from the MMI device, the laser light comprising a combined power of a plurality of input laser light sources from the plurality of second waveguides.

25. The magnetic medium driver of claim 23, wherein the multi-channel laser emitted by the VCSEL device has at least partially overlapping effective regions, and the multi-channel laser operates at the same frequency.

26. The magnetic dielectric driver of claim 23, wherein the plurality of laser apertures are spaced apart at a pitch between about 2 micrometers and about 5 micrometers.

27. The magnetic medium driver of claim 23, wherein the plurality of laser holes comprises 2 to 16 laser holes.

28. The magnetic dielectric driver of claim 23, wherein the plurality of laser apertures are spaced apart from the second surface at a first distance between about 1 micrometer and about 20 micrometers.

29. The magnetic dielectric driver of claim 23, wherein the multi-channel laser emitted by the VCSEL device is phase-coherent, and wherein the plurality of laser apertures are arranged in a straight line.

30. A magnetic media driver, the magnetic media driver comprising: Magnetic recording head, wherein the magnetic recording head includes: The near-field transducer located at the surface facing the medium, i.e., the MFS, is called the NFT; A vertical-cavity surface-emitting laser (VCSEL) device is coupled to a first surface opposite to the MFS (Multi-Front-Side Surface Emitting Laser), wherein the VCSEL device includes a second surface facing the first surface, wherein the VCSEL device is capable of emitting multiple laser beams through the second surface, and wherein the multiple laser beams emitted by the VCSEL device are phase-coherent; and A waveguide structure extending between the NFT and the first surface, wherein the waveguide structure includes components for combining the power of the multi-channel laser emitted by the VCSEL device.

31. The magnetic medium driver of claim 30, wherein the multiple lasers operate at the same frequency.

32. The magnetic dielectric driver of claim 30, wherein the multi-channel laser emitted by the VCSEL device has at least partially overlapping effective regions, and each of the multi-channel lasers emitted by the VCSEL device has a power level between about 1 mW and about 10 mW.

33. The magnetic dielectric driver of claim 30, wherein the VCSEL device is coupled to the first surface via one or more contacts, each of the one or more contacts comprising one or more electrodes.

34. The magnetic dielectric driver of claim 30, wherein the first surface includes a plurality of laser apertures aligned with the multiple lasers emitted by the VCSEL device, wherein the plurality of laser apertures are spaced apart from the second surface at a first distance between about 1 micrometer and about 20 micrometers.

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