Thermally assisted magnetic head, magnetic head gimbal assembly and hard disk drive

Abstract

The invention discloses a heat-assisted magnetic head which comprises a sliding block and a light source unit arranged on the sliding block, a transfer bonding pad is provided, a first light source bonding pad of the sliding block and a second light source bonding pad of the sliding block are arranged on the same straight line side by side, the transfer bonding pad is not on the straight line, and a first pole of the light source unit is electrically connected with the first light source bonding pad. The second pole of the light source unit and the second light source bonding pad are electrically connected with the transfer bonding pad, so that the second pole of the light source unit is reliably and electrically connected with the second light source bonding pad; the problem of low yield caused by overlapping of the joint position of the second electrode of the light source unit on the second light source bonding pad and the joint position of the cantilever piece on the second light source bonding pad in practical application is avoided, and the number of original bonding pads does not need to be reduced. Meanwhile, the embodiment of the invention also correspondingly provides a magnetic head gimbal assembly and a hard disk drive.

Description

Technical Field

[0001] The present invention relates to the technical field of hard disk drives, and in particular to a thermally assisted magnetic head, a magnetic head flap assembly and a hard disk drive. Background Art

[0002] A hard disk drive (HDD) is used to write data to or read data from a disk. Figure 1 As shown, a hard disk drive 300 typically includes a plurality of rotatable disks 301 connected to a spindle motor 302, a drive arm 304, and a head gimbal assembly (HGA) 200 mounted at the end of the drive arm 304. The hard disk drive 300 typically also includes a voice-coil motor (VCM) to control the movement of the drive arm 304. The head gimbal assembly 200 includes a magnetic head 230 and a suspension 290 for supporting the magnetic head 230. When the hard disk drive 300 is in operation, the spindle motor 302 rotates the magnetic disks 301 at high speed, and the magnetic head 230 flies above the magnetic disks due to the air pressure generated by the rotation of the magnetic disks 301. Under the control of the voice coil motor, the magnetic head 230 moves radially across the surface of the magnetic disks 301. The magnetic head 230 can read data from or write data to the magnetic disks 301 for different magnetic tracks.

[0003] In heat-assisted magnetic recording (HAMR) technology, the magnetic head includes a slider and a light source unit (such as a laser diode) arranged on the slider. The light source provides energy to a portion of the magnetic recording medium, thereby reducing the coercive force of that portion, and facilitates the writing operation by applying a write magnetic field to the heated portion.

[0004] Currently, a plurality of parallel connection pads are provided on the slider, and a plurality of corresponding electrical connection terminals are provided on the suspension to input control signals to the magnetic head, wherein the plurality of parallel connection pads on the slider include an LDP pad connected to the P-pole of the laser diode and an LDG pad connected to the N-pole of the laser diode. For example, in the related art, see Figure 2 When the N-pole of the laser diode is connected to the LDG pad on the slider, the N-pole of the laser diode overlaps with the electrical connection end of the cantilever at the LDG pad, which can easily lead to unstable bonding and low yield of the magnetic head. To solve the above problem, in the related art, please refer to Figure 3By reducing the number of parallel connection pads on the slider, more space is left for the LDG pad, that is, the area of ​​the LDG pad is increased, so that the laser diode's N-pole connection location on the LDG pad does not overlap with the cantilever's electrical connection end on the LDG pad. However, this method of reducing the number of parallel connection pads on the slider is difficult to meet the multi-performance requirements of the magnetic head, because the slider's multiple parallel connection pads are used for other functions besides controlling the laser diode, such as readers, writers, and HDI sensors. Summary of the Invention

[0005] In view of the shortcomings of the prior art, an embodiment of the present invention provides a thermally assisted magnetic head, which includes a slider and a light source unit provided on the slider;

[0006] The slider is provided with a first light source pad, a second light source pad and a transfer pad, the first light source pad and the second light source pad are arranged side by side on the same straight line, and the transfer pad is not on the straight line; the light source unit has a first pole and a second pole, the first pole is electrically connected to the first light source pad, the second pole is electrically connected to the transfer pad, and the second light source pad is electrically connected to the transfer pad.

[0007] As a preferred solution, the transfer pad is a pad electrically connected only to the second electrode and the second light source pad.

[0008] As a preferred solution, the transfer pad and the light source unit are arranged side by side.

[0009] As a preferred solution, the transfer pad is an electric grinding guide pad.

[0010] As a preferred solution, the second electrode is connected to the transfer pad via wire bonding or solder balls.

[0011] As a preferred solution, the solder ball connection is SBB bridge welding.

[0012] As a preferred solution, the slider is provided with a mounting surface, and the first light source solder pad, the second light source solder pad and the transfer solder pad are all provided on the mounting surface; the first pole is provided on the first surface of the light source unit, and the second pole is provided on the second surface of the light source unit, the first surface is opposite to the second surface, and the first surface is provided on the mounting surface.

[0013] As a preferred embodiment, the light source unit is a laser diode, the first pole is one of the P pole and the N pole of the laser diode, the first light source pad is the corresponding P pole pad or the N pole pad, the second pole is the other of the P pole and the N pole of the laser diode, and the second light source pad is the corresponding P pole pad or the N pole pad.

[0014] In order to solve the same technical problem, an embodiment of the present invention further provides a head gimbal assembly including the thermally assisted magnetic head.

[0015] In order to solve the same technical problem, an embodiment of the present invention further provides a hard disk drive including the above-mentioned head gimbal assembly.

[0016] Compared to the prior art, the beneficial effects of the embodiments of the present invention are as follows: the embodiments of the present invention provide a thermally assisted magnetic head, which includes a slider and a light source unit disposed on the slider. By providing a transfer pad, the first light source pad of the slider and the second light source pad of the slider are arranged side by side on the same straight line, and the transfer pad is not on the straight line, and the first pole of the light source unit is electrically connected to the first light source pad, and the second pole of the light source unit and the second light source pad are electrically connected to the transfer pad respectively. Thus, under the premise of achieving a reliable electrical connection between the second pole of the light source unit and the second light source pad, the problem of low yield caused by the second pole of the light source unit overlapping with the cantilever member at the second light source pad at the junction position in actual application is avoided, and the number of existing pads does not need to be reduced. At the same time, the embodiments of the present invention also provide a head flap assembly and a hard disk drive. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural diagram of a hard disk drive in the related art.

[0018] Figure 2 It is a schematic diagram of a connection method between a laser diode and a connecting pad of a slider in the related art;

[0019] Figure 3 is a schematic diagram of another connection method between a laser diode and a connecting pad of a slider in the related art;

[0020] Figure 4 is a schematic structural diagram of a thermally assisted magnetic head according to an embodiment of the present invention;

[0021] Figure 5 yes Figure 4 Left view of;

[0022] Figure 6 is a schematic diagram of the assembly between the thermally assisted magnetic head and the suspension in an embodiment of the present invention;

[0023] Figure 7 yes Figure 6 Left view of;

[0024] Figure 8 Schematic diagram of the second electrode of the light source unit and the transfer pad being welded via an SBB bridge in an embodiment of the present invention;

[0025] Figure 9 yes Figure 8 Left view of;

[0026] Figure 10 is a schematic diagram of the assembly between the thermally assisted magnetic head and the suspension in an embodiment of the present invention;

[0027] Figure 11 yes Figure 10 Left view of;

[0028] Figure 12 is a schematic diagram of an embodiment of the present invention in which the transfer pad is located on the left side of the light source unit;

[0029] Figure 13 yes Figure 12 Bottom view of

[0030] Figure 14 2 is a schematic structural diagram of a thermally assisted magnetic head in which the transfer pad is an electrically ground guide pad in an embodiment of the present invention;

[0031] Figure 15 yes Figure 14 Left view of;

[0032] Figure 16 yes Figure 14 Bottom view of

[0033] Figure 17 It is a structural diagram of the LOS structure in the related art;

[0034] Figure 18 is a schematic structural diagram of the LIT structure in an embodiment of the present invention;

[0035] Among them, 300, hard disk drive; 302, spindle motor; 301, magnetic disk; 304, drive arm; 200, head fold assembly; 230, magnetic head; 290, cantilever; 1, thermally assisted magnetic head; 2, slider; 21, first light source pad; 22, second light source pad; 23, transfer pad; 24, mounting surface; 25, front surface; 26, air bearing surface; 3, light source unit; 31, first pole; 32, second pole; 4, cantilever; 5, waveguide; 6, surface plasmon antenna; 10, slider; 20, laser diode; 30, base; 40, surface plasmon antenna; 50, waveguide. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0037] See also Figures 4 to 7 , which is a schematic structural diagram of a thermally assisted magnetic head 1 according to an embodiment of the present invention. The thermally assisted magnetic head 1 according to the embodiment of the present invention comprises a slider 2 and a light source unit 3 provided on the slider 2;

[0038] The slider 2 is provided with a first light source pad 21, a second light source pad 22 and a transfer pad 23. The first light source pad 21 and the second light source pad 22 are arranged side by side on the same straight line, and the transfer pad 23 is not on the straight line; the light source unit 3 has a first pole 31 and a second pole 32. The first pole 31 is electrically connected to the first light source pad 21, the second pole 32 is electrically connected to the transfer pad 23, and the second light source pad 22 is electrically connected to the transfer pad 23.

[0039] In an embodiment of the present invention, the thermally assisted magnetic head 1 includes a slider 2 and a light source unit 3 arranged on the slider 2. By providing a transfer pad 23, the first light source pad 21 of the slider 2 and the second light source pad 22 of the slider 2 are arranged side by side on the same straight line, the transfer pad 23 is not on the straight line, and the first pole 31 of the light source unit 3 is electrically connected to the first light source pad 21, and the second pole 32 of the light source unit 3 and the second light source pad 22 are electrically connected to the transfer pad 23 respectively. Therefore, on the premise of achieving reliable electrical connection between the second pole 32 of the light source unit 3 and the second light source pad 22, the problem of low yield caused by the overlap of the second pole 32 of the light source unit 3 at the joint position of the second light source pad 22 and the cantilever part 4 at the joint position of the second light source pad 22 in actual application is avoided, and there is no need to reduce the number of original pads.

[0040] See also Figure 4 、 Figure 8 and Figure 12In an optional embodiment, the transfer pad 23 is a pad electrically connected only to the second pole 32 and the second light source pad 22. In this embodiment, by adding a transfer pad 23 on the basis of the original pads, and connecting the second pole 32 of the light source unit 3 and the second light source pad 22 to the transfer pad 23 respectively, while achieving a reliable electrical connection between the second pole 32 of the light source unit 3 and the second light source pad 22, the problem of low yield caused by the overlap of the joint position of the second pole 32 of the light source unit 3 at the second light source pad 22 and the joint position of the cantilever member 4 at the second light source pad 22 in actual application is avoided, and the number of original pads does not need to be reduced.

[0041] See also Figure 4 、 Figure 6 、 Figure 8 、 Figure 10 、 Figure 12 、 Figure 14 In a specific implementation, the electrical connection between the transfer pad 23 and the second light source pad 22 can be achieved by, for example, a printed circuit. The first pole 31 of the light source unit 3 and the first light source pad 21 can be electrically connected by, for example, a printed circuit.

[0042] See also Figure 6 、 Figure 7 、 Figure 12 and Figure 13 , the transfer pad 23 is arranged side by side with the light source unit 3. For example, see Figure 12 and Figure 13 The transfer pad 23 can be set on the left side of the light source unit 3, or on the right side of the light source unit 3, as shown in FIG. Figure 6 and Figure 7 As shown, the second pole 32 of the light source unit 3 is connected to the transfer pad 23 , thereby improving the convenience of actual operation and making full use of the space of the slider 2 .

[0043] See also Figures 14 to 16 In another optional embodiment, the transfer pad 23 is an electrical lapping guide pad. It should be noted that the electrical lapping guide (ELG) pad is mainly used in the lapping process of the slider 2. When the thermally assisted magnetic head 1 is actually used, the ELG pad is not electrically connected to other components. Therefore, using the electrical lapping guide pad as the transfer pad 23 does not affect other functions of the thermally assisted magnetic head 1.

[0044] See also Figure 4In an optional embodiment, the second electrode 32 is bonded to the transfer pad 23 by a wire. Of course, the second electrode 32 can also be bonded to the transfer pad 23 by solder ball bonding (SBB). Figure 8 In this embodiment, the connection reliability between the second electrode 32 of the light source unit 3 and the transfer pad 23 is ensured by wire bonding or solder ball connection.

[0045] See also Figures 8 to 11 In an optional embodiment, the solder ball connection is SBB bridge welding. In this embodiment, the electrical connection between the second pole 32 of the light source unit 3 and the transfer pad 23 is achieved through SBB bridge welding, thereby further ensuring the connection reliability between the second pole 32 of the light source unit 3 and the transfer pad 23.

[0046] See also Figure 8 and Figure 9 In an optional embodiment, the slider 2 is provided with a mounting surface 24, and the first light source soldering pad 21, the second light source soldering pad 22 and the transfer soldering pad 23 are all provided on the mounting surface 24; the first pole 31 is provided on the first surface of the light source unit 3, and the second pole 32 is provided on the second surface of the light source unit 3, the first surface is opposite to the second surface, and the first surface is provided on the mounting surface 24.

[0047] In this embodiment, the first light source pad 21 , the second light source pad 22 , the transfer pad 23 and the light source unit 3 are all arranged on the same surface of the slider 2 , thereby facilitating a more compact circuit layout.

[0048] In an optional embodiment, the light source unit 3 is a laser diode. Figure 17The LOS (LD On Slider) structure is one of the traditional HAMR structures, that is, a structure in which the laser diode 20 is provided on the slider 10. It requires three components: the laser diode 20, the base 30, and the slider 10. Among them, the laser diode 20 is connected to the base 30. This structure is called an LDU. The LDU is optically aligned and is connected to the back of the slider 10. This assembly component is usually called an L-slider (L-SLD). The HAMR structure in this embodiment is a LIT (LD In Trailing surface) structure, that is, a structure in which the laser diode is provided in the trailing surface of the slider 2. Specifically, in the LIT structure, a cavity is provided on the trailing surface of the slider 2, and the laser diode is provided in the cavity. This design of combining a laser diode in a cavity does not require a special laser diode base and its connecting device, thereby reducing material and process costs. In addition, the LIT structure can also better realize more multi-stacked HDDs. Please refer to Figure 1 In this embodiment, the mounting surface 24 is the trailing surface of the slider 2. In addition, the slider 2 also has a leading surface 25 and an air bearing surface (ABS) 26. The leading surface 25 is opposite to the trailing surface. Figure 9 shown.

[0049] See also Figure 9 and Figure 18 In actual applications, the air bearing surface 26 of the slider 2 faces the magnetic recording medium. The laser light emitted by the laser diode is transmitted through the waveguide 5 and converted into near-field light by the surface plasmon antenna 6 to heat the magnetic recording medium, thereby reducing the coercive force of the magnetic recording medium and facilitating the magnetic head to write data into the magnetic recording medium.

[0050] In a specific implementation, the first pole 31 is one of the P pole of the laser diode and the N pole of the laser diode, the first light source pad 21 is the corresponding P pole pad or N pole pad, the second pole 32 is the other of the P pole of the laser diode and the N pole of the laser diode, and the second light source pad 22 is the corresponding P pole pad or N pole pad.

[0051] Exemplarily, if the first pole 31 is the P pole of the laser diode, the first light source pad 21 is the corresponding P pole pad, the second pole 32 is the N pole of the laser diode, and the second light source pad 22 is the corresponding N pole pad; if the first pole 31 is the N pole of the laser diode, the first light source pad 21 is the corresponding N pole pad, the second pole 32 is the P pole of the laser diode, and the second light source pad 22 is the corresponding P pole pad.

[0052] It should be noted that in the specific implementation, please refer to Figures 14 to 16 The slider 2 is further provided with a waveguide 5, and the light emitted by the light source unit 3 is transmitted through the waveguide 5. For details, please refer to other related technologies and no further details will be given here.

[0053] Accordingly, the embodiment of the present invention further provides a head gimbal assembly 200, see Figure 1 The HGA 200 includes the thermally assisted magnetic head of any of the above-described embodiments. In a specific implementation, the HGA further includes a suspension 290 for supporting the magnetic head. The suspension 290 is provided with a plurality of electrical connection terminals, and the slider 2 is provided with a plurality of connection pads for corresponding electrical connection to the plurality of electrical connection terminals of the suspension. In this way, the control circuit can transmit control signals via the electrical connection terminals of the suspension 290 and the connection pads of the slider 2.

[0054] Accordingly, see Figure 1 An embodiment of the present invention further provides a hard disk drive 300 comprising the aforementioned head gimbal assembly 200. In a specific implementation, the hard disk drive 300 further comprises a plurality of rotatable disks 301 connected to a spindle motor 302 and a drive arm 304, with the head gimbal assembly 200 mounted at the end of the drive arm 304. Typically, the hard disk drive 300 further comprises a voice coil motor to control the movement of the drive arm 304. When the hard disk drive 300 is in operation, the spindle motor 302 causes the disks 301 to rotate at high speed, and the magnetic head flies above the disks due to the air pressure generated by the rotation of the disks 301. Under the control of the voice coil motor, the magnetic head moves radially on the surface of the disks 301. The magnetic head can read data from or write data to the disks 301 for different magnetic tracks.

[0055] Compared to the prior art, the embodiments of the present invention have the following advantages: The embodiments of the present invention provide a thermally assisted magnetic head 1, comprising a slider 2 and a light source unit 3 disposed on the slider 2. By providing a transfer pad 23, with the first light source pad 21 and the second light source pad 22 of the slider 2 arranged side by side on the same straight line, while the transfer pad 23 is not on the straight line, and the first pole 31 of the light source unit 3 is electrically connected to the first light source pad 21, and the second pole 32 of the light source unit 3 is electrically connected to the second light source pad 22, respectively. Thus, while achieving reliable electrical connection between the second pole 32 of the light source unit 3 and the second light source pad 22, the embodiment of the present invention avoids the problem of low yield caused by the second pole 32 of the light source unit 3 overlapping with the second light source pad 22 at the junction of the cantilever 4 and the second light source pad 22 in actual applications, particularly the problem of low yield during SBB welding, without reducing the number of existing pads. Furthermore, the embodiments of the present invention also provide a head gimbal assembly 200 and a hard disk drive 300.

[0056] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A thermally assisted magnetic head, characterized in that: It includes a slider and a light source unit provided on the slider; The slider is provided with a first light source pad, a second light source pad and a transfer pad, the first light source pad and the second light source pad are arranged side by side on the same straight line, and the transfer pad is not on the straight line; the light source unit has a first pole and a second pole, the first pole is electrically connected to the first light source pad, the second pole is electrically connected to the transfer pad, and the second light source pad is electrically connected to the transfer pad.

2. The thermally assisted magnetic head according to claim 1, wherein: The transfer pad is a pad electrically connected only to the second electrode and the second light source pad.

3. The thermally assisted magnetic head according to claim 2, wherein: The transfer pad and the light source unit are arranged side by side.

4. The thermally assisted magnetic head according to claim 1, wherein: The transfer pad is an electric grinding guide pad.

5. The thermally assisted magnetic head according to claim 1, wherein: The second electrode is connected to the transfer pad by wire bonding or solder balls.

6. The thermally assisted magnetic head according to claim 5, wherein: The solder ball connection is SBB bridge welding.

7. The thermally assisted magnetic head according to claim 1, wherein: The slider is provided with a mounting surface, and the first light source solder pad, the second light source solder pad and the transfer solder pad are all provided on the mounting surface; the first pole is provided on the first surface of the light source unit, and the second pole is provided on the second surface of the light source unit, the first surface is opposite to the second surface, and the first surface is provided on the mounting surface.

8. The thermally assisted magnetic head according to claim 1, wherein: The light source unit is a laser diode, the first pole is one of the P pole and the N pole of the laser diode, the first light source pad is the corresponding P pole pad or the N pole pad, the second pole is the other of the P pole and the N pole of the laser diode, and the second light source pad is the corresponding P pole pad or the N pole pad.

9. A head gimbal assembly, characterized in that: The thermally assisted magnetic head comprises the thermally assisted magnetic head according to any one of claims 1 to 8.

10. A hard disk drive, characterized in that: The invention comprises the head gimbal assembly as claimed in claim 9.

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