Disk drive suspension, electronic component, and method for connecting suspension and electronic component

Abstract

To provide a suspension for a disk device, an electronic component, and a method for connecting the suspension with the electronic component for suitably connecting between terminals.SOLUTION: A suspension for a disk device according to one embodiment includes a load beam, a flexure superimposed on the load beam, a first terminal provided on the flexure, and a first bump placed on the upper surface of the first terminal. The first terminal has: a narrow width portion having a first width in a first direction, and including a center of the first terminal; and a wide width portion having a second width larger than the first width in the first direction, and aligned with the narrow width portion in a second direction intersecting the first direction. The first bump has a first height at the center on the basis of the lower surface of the first terminal. The first height is larger than the first width.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a disk drive suspension used in a hard disk drive or the like, an electronic component mounted on the suspension, and a method for connecting the suspension and the electronic component. [Background technology]

[0002] Hard disk drives (HDDs) are used in information processing devices such as personal computers. Hard disk drives include a magnetic disk that rotates around a spindle and a carriage that rotates around a pivot shaft. The carriage has an actuator arm and rotates around the pivot shaft in the track width direction of the disk by a positioning motor such as a voice coil motor.

[0003] A disk drive suspension (hereinafter simply referred to as the suspension) is attached to the actuator arm. The suspension includes a load beam and a flexure placed on the load beam. A slider that constitutes a magnetic head is mounted on a gimbal portion formed near the tip of the flexure. The slider is equipped with an element (transducer) for reading and writing data.

[0004] The flexure has multiple wirings. These wirings are connected to terminals (pads) on the tip side of the suspension and terminals on the tail side. The terminals on the tip side are connected to terminals on the slider by solder. The terminals on the tail side are connected to a flexible printed circuit board (FPC) by solder.

[0005] As a method for connecting terminals with solder, for example, the techniques described in Patent Documents 1 and 2 are known. In the methods described in these documents, solder bumps are formed on the terminals, the bumps are flattened, and the flattened bumps are brought close to the mating terminals. The bumps are then melted and bonded to the mating terminals. Flattening the bumps increases the tolerance for aligning the terminals.

[0006] In recent years, as the performance of suspensions has become more sophisticated, the number of wiring and terminals provided on flexures has also been increasing. As a result, if the spacing between terminals is reduced, there is a possibility that bumps formed on adjacent terminals may short-circuit.

[0007] One possible solution to this problem is to reduce the amount of solder that makes up the bumps, but this can lead to poor connections between the terminals.

[0008] Furthermore, Patent Documents 3 and 4 disclose methods for narrowing the width of the central portion of a terminal in order to reduce the height and width of the central portion of a bump. However, if the height of the bump is reduced, there is a possibility that the bump will not be properly bonded to the mating bump when melted after planarization, as described above. In addition, since the difference in bump height before and after planarization becomes smaller, the tolerance for aligning the terminals with each other may decrease. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 7-320434 [Patent Document 2] Japanese Patent Application Publication No. 11-110925 [Patent Document 3] Japanese Utility Model Application Publication No. 5-67048 [Patent Document 4] Japanese Patent Application Laid-Open No. 2013-33570 Summary of the Invention [Problem to be solved by the invention]

[0010] As described above, there is room for improvement in the connection between the terminals of a suspension and the terminals of an electronic component such as a slider or a flexible printed circuit board. Therefore, an object of the present invention is to provide a suspension and an electronic component that enable good connection between the terminals, and a method for connecting a suspension and an electronic component. [Means for solving the problem]

[0011] A disk drive suspension according to one embodiment includes a load beam, a flexure overlaid on the load beam, a first terminal provided on the flexure, and a first bump disposed on an upper surface of the first terminal. The first terminal includes a narrow portion having a first width in a first direction and including a center of the first terminal, and a wide portion having a second width in the first direction greater than the first width and aligned with the narrow portion in a second direction intersecting the first direction. The first bump has a first height at the center, based on the lower surface of the first terminal. The first height is greater than the first width.

[0012] A connection method according to one embodiment is a connection method for electrically connecting the suspension for a disk drive to an electronic component having a second terminal and a second bump arranged on an upper surface of the second terminal, and includes flattening the first bump, aligning the suspension with the electronic component so that the first bump and the second bump are adjacent to each other and a first plane including the upper surface of the first terminal intersects with a second plane including the upper surface of the second terminal, and connecting the first bump and the second bump by melting the first bump and the second bump.

[0013] An electronic component according to one embodiment is electrically connected to a disk drive suspension. The electrical component includes a second terminal and a second bump disposed on an upper surface of the second terminal. The second terminal includes a narrow portion having a first width in a first direction and including a center of the second terminal, and a wide portion having a second width in the first direction greater than the first width and aligned with the narrow portion in a second direction intersecting the first direction. The second bump has a first height at the center, based on the lower surface of the second terminal. The first height is greater than the first width.

[0014] A connection method according to one embodiment electrically connects an electronic component to a suspension for a disk device, the suspension having a first terminal and a first bump arranged on the upper surface of the first terminal, and includes flattening the second bump, aligning the suspension with the electronic component so that the first bump and the second bump are adjacent to each other and a first plane including the upper surface of the first terminal intersects with a second plane including the upper surface of the second terminal, and connecting the first bump and the second bump by melting the first bump and the second bump. [Effects of the Invention]

[0015] According to the present invention, it is possible to provide a suspension and an electronic component that enable good connection between terminals, and a method for connecting a suspension and an electronic component. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a schematic perspective view showing an example of a disk device. [Figure 2] FIG. 2 is a schematic cross-sectional view showing a part of the disk device. [Figure 3] FIG. 3 is a schematic plan view showing an example of a head gimbal assembly including a suspension and a slider. [Figure 4]FIG. 4 is a schematic perspective view showing an example of a connection structure between a suspension and a flexible printed circuit board. [Figure 5] FIG. 5 is a schematic perspective view showing an example of a connection structure between a suspension and a slider. [Figure 6] FIG. 6 is a schematic plan view showing an example of a terminal according to the first embodiment. [Figure 7] FIG. 7 is a schematic plan view of an enlarged terminal. [Figure 8] FIG. 8 is a schematic cross-sectional view of the terminal (wide portion) and the bump taken along the line VIII-VIII in FIG. [Figure 9] FIG. 9 is a schematic cross-sectional view of the terminal (narrow width portion) and the bump taken along the line IX-IX in FIG. [Figure 10] FIG. 10 is a flowchart showing an example of a method for connecting a suspension and an electronic component. [Figure 11] FIG. 11 is a schematic cross-sectional view showing the terminals and the flattened bumps. [Figure 12] FIG. 12 is a schematic cross-sectional view of the aligned suspension and flexible printed circuit board. [Figure 13] FIG. 13 is a schematic cross-sectional view showing the state in which the bumps, which have been integrated after melting, have cooled and solidified. [Figure 14] FIG. 14 is a table showing examples and comparative examples of terminals and bumps. [Figure 15] FIG. 15 is a schematic plan view of a terminal according to a first modified example. [Figure 16] FIG. 16 is a schematic plan view of a terminal according to a second modified example. [Figure 17] FIG. 17 is a schematic plan view of a terminal according to a third modified example. [Figure 18] FIG. 18 is a schematic cross-sectional view showing another structure that can be applied to a terminal. DETAILED DESCRIPTION OF THE INVENTION

[0017] [First embodiment] The first embodiment will be described with reference to FIGS. <Disk device> 1 is a schematic perspective view showing an example of a disk drive (HDD) 1. This disk drive 1 includes a case 2, a plurality of disks 4 that rotate around a spindle 3, a carriage 6 that can rotate around a pivot shaft 5, a positioning motor (voice coil motor) 7 for driving the carriage 6, and a connector 8. The case 2 is sealed with a lid (not shown). The connector 8 is connected to a control board (not shown).

[0018] FIG. 2 is a schematic cross-sectional view showing a part of the disk device 1. As shown in FIGS. 1 and 2, the carriage 6 is provided with a plurality of arms 6a (carriage arms). A suspension 10 is attached to the tip of each arm 6a. A slider 12 constituting a magnetic head is provided to the tip of each suspension 10. The slider 12 writes data to and reads data from the disk 4. When the disk 4 rotates at high speed, air flows in between the disk 4 and the slider 12, forming an air bearing.

[0019] When the carriage 6 is rotated by the positioning motor 7, the suspension 10 moves in the radial direction of the disk 4. This allows the slider 12 to move to a desired track on the disk 4.

[0020] <Suspension> 3 is a schematic plan view showing an example of a head gimbal assembly including a suspension 10 and a slider 12. The suspension 10 includes a base plate 15, a load beam 16, and a flexure 20. The base plate 15 has a boss portion 15a. The boss portion 15a is fixed to the arm 6a of the carriage 6 shown in FIGS. 1 and 2.

[0021] The load beam 16 and the flexure 20 are elongated in the longitudinal direction X of the suspension 10. For example, the load beam 16 is formed of a stainless steel plate. The flexure 20 has a tip portion 21 that overlaps the load beam 16 and a tail portion 22 that extends from the tip portion 21 to the rear of the base plate 15 (downward in the figure).

[0022] A pad portion 23 is provided at the end of the tail portion 22. One end of the flexible printed circuit board 11 is connected to the pad portion 23. The other end of the flexible printed circuit board 11 is connected to the connector 8 shown in FIG. 1. A tongue 24 that functions as a swingable gimbal portion is formed at the tip portion 21. The slider 12 is mounted on the tongue 24.

[0023] 4 is a schematic perspective view showing an example of a connection structure between the suspension 10 and the flexible printed circuit board 11. For example, the flexure 20 includes a base metal and an insulating layer covering one surface of the base metal. The flexure 20 further includes a plurality of wirings 30 formed on the insulating layer and a plurality of terminals 31 connected to the wirings 30, respectively.

[0024] The terminals 31 are formed on one surface 23a of the tail portion 22 and are arranged at intervals in a direction substantially parallel to the longitudinal direction X, for example.

[0025] The flexible printed circuit board 11 has a plurality of terminals 32 provided on one surface 11a. The surface 11a intersects with the surface 23a at a predetermined angle. In the example of FIG. 4, the surfaces 11a and 23a are perpendicular to each other. Each terminal 32 is connected to a plurality of wirings 34 provided on the flexible printed circuit board 11.

[0026] The multiple terminals 32 are arranged at intervals in a direction substantially parallel to the longitudinal direction X, for example. Each terminal 32 is connected to a corresponding terminal 31 via a conductive connecting member 33. As will be described later, the connecting member 33 is formed by melting and then integrating and solidifying a bump 33A arranged on the terminal 31 before connection and a bump 33B arranged on the terminal 32 before connection. Although ten pairs of terminals 31 and 32 are shown in FIG. 4, the number of terminals 31 and 32 is not limited to this example.

[0027] 5 is a schematic perspective view showing an example of a connection structure between the suspension 10 and the slider 12. In the example shown, the slider 12 has a rectangular parallelepiped shape, but is not limited to this example. The slider 12 is mounted on a tongue 24.

[0028] Most of the wiring 30 described above is formed along a path that passes through the tail portion 22 and the tip portion 21 of the flexure 20 and reaches the tongue 24. Some of the multiple wirings 30 shown in FIG. 4 are connected, for example, at the tip portion 21, to electronic components other than the slider 12 of the suspension 10. An example of such an electronic component is an actuator element that causes the tongue 24 to swing.

[0029] The flexure 20 includes a plurality of terminals 41 formed on one surface 24a (the surface on which the slider 12 is mounted) of the tongue 24. The plurality of terminals 41 are arranged at intervals in a direction perpendicular to the longitudinal direction X, for example.

[0030] The slider 12 has a side surface 12a that intersects with the longitudinal direction X. The side surface 12a intersects with the surface 24a at a predetermined angle. In the example of Fig. 5, the side surface 12a and the surface 24a are perpendicular to each other.

[0031] The slider 12 has a plurality of elements 12b, such as MR elements, that can convert magnetic signals into electrical signals. These elements 12b read data from the disk 4. The slider 12 also has a coil that generates a magnetic field for writing data to the disk 4.

[0032] The slider 12 further includes a plurality of terminals 42 provided on the side surface 12a. These terminals 42 are arranged at intervals in a direction perpendicular to the longitudinal direction X, for example. Each terminal 42 is connected to a corresponding terminal 41 via a conductive connecting member 43. As will be described later, the connecting member 43 is formed by melting, integrating, and solidifying a bump 43A arranged on the terminal 41 before connection and a bump 43B arranged on the terminal 42 before connection. Although six pairs of terminals 41 and 42 are shown in FIG. 5, the number of terminals 41 and 42 is not limited to this example.

[0033] <Terminal structure> 6 is a schematic plan view showing an example of terminals 31, 32 before connection according to this embodiment. The multiple terminals 31 provided on the pad portion 23 are arranged at regular intervals G in a first direction D1. The terminals 31 have an elongated shape in a second direction D2 that intersects with the first direction D1. In this embodiment, the first direction D1 and the second direction D2 are perpendicular to each other. The first direction D1 is, for example, parallel to the longitudinal direction X.

[0034] One end of each terminal 31 in the second direction D2 is connected to the wiring 30. A conductive bump 33A is disposed on each terminal 31. The bump 33A is made of a metal material. The metal material of the bump 33A is, for example, an alloy, and preferably solder.

[0035] Similar to the terminals 31, the multiple terminals 32 provided on the flexible printed circuit board 11 are arranged at regular intervals G in the first direction D1. The shape of the terminals 32 is, for example, the same as that of the terminals 31. One end of each terminal 32 in the second direction D2 is connected to a wiring 34. A conductive bump 33B is disposed on each terminal 32. The bump 33B is made of the same material as the bump 33A.

[0036] The terminal 41 provided on the tongue 24 and the terminal 42 provided on the slider 12 can have the same shape and arrangement as the terminals 31 and 32. A bump 43A similar to the bump 33A is arranged on the terminal 41 before it is connected to the terminal 42. A bump 43B similar to the bump 33B is arranged on the terminal 42 before it is connected to the terminal 41. In Fig. 6, the reference numerals of the tongue 24, the slider 12, the terminals 41 and 42, and the bumps 43A and 43B are written next to the corresponding elements.

[0037] The structures of terminal 31 and bump 33A will be described below with reference to Figures 7 to 9. The same structures as terminal 31 and bump 33A described with reference to Figures 7 to 9 can be applied to terminal 32 and bump 33B. Furthermore, the same structures as terminal 31 and bump 33A described with reference to Figures 7 to 9 can be applied to terminals 41 and 42 and bumps 43A and 43B arranged thereon.

[0038] 7 is a schematic plan view of an enlarged terminal 31. The terminal 31 has a first side S1 and a second side S2 that intersect with the first direction D1, and a third side S3 and a fourth side S4 that intersect with the second direction D2. These sides S1, S2, S3, and S4 form the outer shape of the terminal 31. The first side S1 and the second side S2 are longer than the third side S3 and the fourth side S4. The wiring 30 is connected to the third side S3.

[0039] The first side S1 and the second side S2 each have a recess R that is recessed toward the center O of the terminal 31 in the first direction D1. The center O is the point where the center line C1 of the terminal 31 in the first direction D1 intersects the center line C2 of the terminal 31 in the second direction D2. The center line C1 is parallel to the second direction D2, and the center line C2 is parallel to the first direction D1. The terminal 31 has, for example, an outer shape that is line-symmetric with respect to each of the center lines C1 and C2, but is not limited to this example.

[0040] Due to the provision of the recess R, in the outer shape of the terminal 31, the central portion between both ends in the second direction D2 is constricted more than both ends in the second direction D2. Specifically, the terminal 31 has a narrow portion NP and a pair of wide portions WP. The narrow portion NP is the portion corresponding to the recess R and is located between the pair of wide portions WP in the second direction D2. That is, the narrow portion NP and the wide portions WP are arranged side by side in the second direction D2. The narrow portion NP includes the center O.

[0041] The narrow portion NP has a width Wa1 (first width) in the first direction D1. Each wide portion WP has a width Wa2 (second width) in the first direction D1. The width Wa2 is larger than the width Wa1 (Wa1 < Wa2). In the example of FIG. 7, the length of the narrow portion NP in the second direction D2 is larger than the length of each wide portion WP in the second direction D2. However, the length of the narrow portion NP in the second direction D2 may be smaller than the length of each wide portion WP in the second direction D2.

[0042] The bump 33A shown by the broken line is disposed on the upper surface F1 of the terminal 31 in the narrow portion NP and each wide portion WP. The bump 33A protrudes in the first direction D1 more than the first side S1 and the second side S2 in the recess R.

[0043] 8 is a schematic cross-sectional view of the terminal 31 (wide portion WP) and the bump 33A taken along line VIII-VIII in FIG. 7. The terminal 31 includes a conductive layer 310 and a plating layer 311 covering the upper and side surfaces of the conductive layer 310. For example, the conductive layer 310 and the plating layer 311 are formed of different metal materials. The wiring 30 is formed integrally with the conductive layer 310, for example, from the same metal material as the conductive layer 310.

[0044] The lower surface F2 of the terminal 31 is in contact with the surface 23a of the pad portion 23. The surface 23a corresponds to the surface of an insulating layer such as polyimide. The lower surface F2 corresponds to the surface of the conductive layer 310 that is not covered with the plating layer 311. The upper surface F1 of the terminal 31 corresponds to the surface of the plating layer 311.

[0045] The bump 33A covers the top surface F1. In the example of Fig. 8, the bump 33A does not contact the side surfaces of the terminal 31 on the first side S1 and the second side S2, but the bump 33A may cover at least a portion of these side surfaces. In the cross section of Fig. 8, the surface RF of the bump 33A has a shape corresponding to a portion of an ellipse.

[0046] Fig. 9 is a schematic cross-sectional view of the terminal 31 (narrow portion NP) and the bump 33A taken along line IX-IX in Fig. 7. This cross section is taken along the center line C2 shown in Fig. 7 and passes through the center O.

[0047] As described above, the width Wa1 of the narrow portion NP is smaller than the width Wa2 of the wide portion WP, so the bump 33A rises upward, which makes the surface RF closer to a perfect circle than in the example of FIG.

[0048] At the center O, the bump 33A has a height Z1 (first height). The height Z1 is based on the lower surface F2 (or surface 23a) of the terminal 31. In other words, the height Z1 corresponds to the distance from the lower surface F2 to the surface RF at the center O. The height Z1 can also be said to be the combined height of the bump 33A and the terminal 31. The height Z1 is greater than the width Wa1 (Z1>Wa1).

[0049] For example, the height of the bump 33A is greatest at the center O. In this case, the height Z1 is the maximum value of the height of the bump 33A. For example, in the cross section of the bump 33A taken along the center line C1 shown in FIG. 7, the height of the bump 33A gradually decreases from the center O toward the third side S3 and the fourth side S4. In this cross section, it can also be said that the height of the bump 33A at the narrow portion NP is greater overall than the height of the bump 33A at the wide portion WP.

[0050] In the cross section of Fig. 9, the bump 33A has a width Wb1. For example, the width Wb1 is greater than the width Wa1 (Wb1>Wa1). As can be seen from the outline of the bump 33A in Fig. 7, the width in the first direction D1 of the bump 33A arranged on the wide portion WP is greater than the width in the first direction D1 of the bump 33A arranged on the narrow portion NP.

[0051] The bump 33A is formed by screen-printing a layer of material, such as solder, that will become the base of the bump 33A on the upper surface F1 of the terminal 31, melting (reflowing) it in a furnace, and then solidifying it again. Due to surface tension during melting, the surface RF of the bump 33A becomes rounded as shown in Figures 8 and 9.

[0052] In Fig. 9, the outer shapes of the terminal 31X and bump 33X according to the comparative example are indicated by dashed lines. The terminal 31X does not have a recess R. That is, the terminal 31X shown in Fig. 9 has the same shape as the terminal 31 in the cross section of Fig. 8. The width of the bump 33X formed on such a terminal 31X is greater than the width Wb1.

[0053] <How to connect the suspension and electronic components> FIG. 10 is a flowchart showing an example of a method for connecting the suspension 10 and electronic components (flexible printed circuit board 11 and slider 12).

[0054] First, prepare a suspension 10, a flexible printed circuit board 11, and a slider 12 (step ST1). In the suspension 10, bumps 33A described using FIGS. 7 to 9 are arranged on the terminals 31. Bumps 33B, 43A, and 43B similar to the bump 33A are also arranged on the terminal 32 of the flexible printed circuit board 11, the terminal 41 of the suspension 10, and the terminal 42 of the slider 12, respectively.

[0055] Subsequently, flatten the bumps 33A arranged on each terminal 31, the bumps 33B arranged on each terminal 32, the bumps 43A arranged on each terminal 41, and the bumps 43B arranged on each terminal 42 (step ST2). This flattening is performed, for example, by mechanically pressing the bumps 33A, 33B, 43A, and 43B.

[0056] FIG. 11 is a schematic cross-sectional view showing the terminal 31 and the flattened bump 33A. This cross-section is along the center line C2, the same as in FIG. 9, and passes through the center O. Hereinafter, the flattened bump 33A is referred to as bump 33Af.

[0057] In the example of FIG. 11, a flat surface FLT is formed on the surface RF of the bump 33Af. The flat surface FLT is, for example, parallel to the lower surface F2. At the center O, the bump 33Af has a height Z2 (second height). The height Z2 is based on the lower surface F2 of the terminal 31, similar to the height Z1. That is, the height Z2 corresponds to the distance from the lower surface F2 to the surface RF (flat surface FLT) at the center O.

[0058] For example, the height Z2 is smaller than the width Wa1 of the terminal 31 (Z2 < Wa1). That is, the height of the bump 33A at the center O is larger than the width Wa1 before flattening, but smaller than the width Wa1 after flattening. It is preferable that the height Z2 is smaller than the height Z1 by 15% or more.

[0059] In the cross-section of FIG. 11, the bump 33Af has a width Wb2. The width Wb2 is larger than the width Wb1 (Wb1 < Wb2). That is, the width of the bump 33A in the first direction D1 increases due to planarization.

[0060] Note that the flat surface FLT extends not only to the surface RF of the bump 33Af in the narrow-width portion NP but also to the surface RF in the wide-width portion WP. However, in the wide-width portion WP, the height of the bump 33A is smaller than that in the narrow-width portion NP. Therefore, the increase rate of the width of the bump 33A from the width in the wide-width portion WP to the width of the bump 33Af is smaller than the increase rate of the width of the bump 33A from the width in the narrow-width portion NP to the width of the bump 33Af.

[0061] The relationship between the planarized bump 33B and the terminal 32, the relationship between the planarized bump 43A and the terminal 41, and the relationship between the planarized bump 43B and the terminal 42 are the same as the relationship between the bump 33Af and the terminal 31 shown in FIG. 11.

[0062] After planarizing the bumps 33A, 33B, 43A, and 43B, the suspension 10, the flexible printed circuit board 11, and the suspension 10 and the slider 12 are aligned in a state suitable for connection (step ST3 in FIG. 10).

[0063] FIG. 12 is a schematic cross-sectional view of the aligned suspension 10 (pad portion 23) and the flexible printed circuit board 11. Hereinafter, the planarized bump 33B is referred to as the bump 33Bf. In the example shown in FIG. 4, the surface 11a of the flexible printed circuit board 11 and the surface 23a of the pad portion 23 are perpendicular. Therefore, in step ST3, the pad portion 23 and the flexible printed circuit board 11 are aligned so that the surfaces 11a and 23a are perpendicular.

[0064] From another perspective, the pad portion 23 and the flexible printed circuit board 11 are aligned such that the virtual plane V1 (first plane) including the upper surface F1 of the terminal 31 and the virtual plane V2 (second plane) including the upper surface F1 of the terminal 32 intersect. In the example of FIG. 12, these virtual planes V1 and V2 are orthogonal.

[0065] When the pad portion 23 and the flexible printed circuit board 11 are aligned, the bumps 33Af and 33Bf are close to each other. The bumps 33Af and 33Bf may be spaced apart as shown in Fig. 12. Alternatively, the bumps 33Af and 33Bf may be in contact with each other.

[0066] The suspension 10 (tongue 24) and the slider 12 are aligned so that the terminals 41 and 42 are in the same relationship as the terminals 31 and 32 shown in Fig. 12. At this time, the adjacent bumps 43A and 43B may be spaced apart or may be in contact with each other.

[0067] After the suspension 10 and the flexible printed circuit board 11, and the suspension 10 and the slider 12 are aligned, the bumps 33A, 33B, 43A, and 43B are, for example, locally heated to melt (reflow) them (step ST4 in FIG. 10).

[0068] 12, the shapes of the melted bumps 33A and 33B are indicated by dashed lines. By melting, the bumps 33A and 33B approach the shapes they had before being flattened in step ST2. As a result, the bumps 33A and 33B come into contact with each other and are integrated.

[0069] 13 is a schematic cross-sectional view showing a state in which the integrated bumps 33A and 33B have cooled and solidified. When the integrated bumps 33A and 33B have solidified, the above-mentioned connection member 33 is formed. As a result, the terminals 31 and 32 are electrically connected via the connection member 33.

[0070] The melted bumps 43A and 43B are also solidified in an integrated state, forming the above-mentioned connection member 43. As a result, the terminals 41 and 42 are electrically connected via the connection member 43.

[0071] <Effects of the embodiment> The following is an example of the effects obtained from this embodiment. Note that, although the following description mainly focuses on the terminal 31 and the bump 33A, similar effects can also be obtained with respect to the terminal 32 and the bump 33B, the terminal 41 and the bump 43A, and the terminal 42 and the bump 43B.

[0072] When the terminals 31 need to be arranged at high density, the interval G shown in FIG. 6 becomes smaller. In this case, the risk of short-circuiting between the bumps 33A arranged on adjacent terminals 31 increases. This risk becomes particularly pronounced when the bumps 33A are flattened as in this embodiment. If the terminals 31 have a simple rectangular shape, the width of the bumps 33A is greatest at the center in the second direction D2 before and after flattening.

[0073] In contrast, in this embodiment, the terminals 31 have recesses R. This reduces the width of the bumps 33A at the central portions (narrow portions NP) before and after flattening. As a result, the risk of short-circuiting between the bumps 33A arranged on adjacent terminals 31 can be reduced.

[0074] Another method for reducing the risk of short circuits is to reduce the number of bumps 33A disposed on the terminals 31. However, in this case, the height of the bumps 33A before planarization is also reduced. This may result in a poor connection between the terminals 31 and 32, such as a failure to contact the bumps 33A and 33B that are melted after alignment, as shown in FIG. 12.

[0075] In contrast, in this embodiment, the height Z1 at the center O of the bump 33A before planarization is greater than the width Wa1 of the terminal 31 at the narrow portion NP. If the height Z1 is ensured to this extent, the melted bumps 33A and 33B are well connected after planarization.

[0076] In this embodiment, the bumps 33A and 33B are flattened before aligning the suspension 10 and the flexible printed circuit board 11. If alignment were performed without flattening, the bumps 33A and 33B might interfere with each other, reducing the accuracy of alignment. In contrast, if the bumps 33A and 33B are flattened, the bumps 33Af and 33Bf are less likely to interfere with each other after flattening, thereby improving the accuracy of alignment. Even if there is a gap between the bumps 33Af and 33Bf before melting, the bumps 33Af and 33Bf return to their pre-flattened shape after melting, increasing their height. This allows the bumps 33A and 33B to be connected.

[0077] As described above, the terminal 31X according to the comparative example shown in Fig. 9 does not have the recess R. If the bump 33X arranged on this terminal 31X has the same height Z1 as the bump 33A at the center O, the amount of material constituting the bump 33A can be made less than that of the bump 33X in the vicinity of the cross section shown in Fig. 9. As a result, the amount of material constituting the bump 33A can be reduced while increasing the height Z1 of the bump 33A at the center O.

[0078] In this embodiment, a method for increasing the height of the bump 33A near the center O by providing narrow portions NP between the wide portions WP has been disclosed. Another method for increasing the height of the bump 33A near the center O is to form the terminal 31 with an overall width equal to that of the narrow portions NP. However, in this case, when the bump 33A is formed by screen printing and then melted to form the shape of the bump 33A as shown in FIG. 9, the bump 33A may fall off the terminal 31.

[0079] In contrast, if the wide portions WP are provided as in this embodiment, the portion of the molten bump 33A that cannot be held by the narrow portions NP flows into the wide portions WP. This makes it difficult for the bump 33A to fall off the terminal 31. In this embodiment, the width of the terminal 31 is reduced to ensure the height of the bump 33A, and both ends of the terminal 31 in the second direction D2 are widened to prevent the bump 33A from falling off the terminal 31. In addition to the above, various other advantageous effects can be obtained from this embodiment.

[0080] <Example> FIG. 14 is a table showing examples 1 and 2 and a comparative example of terminals 31 and bumps 33A. The terminals 31 according to examples 1 and 2 both have the shape shown in FIG. 7. The terminal 31X according to the comparative example does not have a recess R. The width in the first direction D1 of the wide portion WP of the terminal 31 according to examples 1 and 2 is the same as the width in the first direction D1 of the terminal 31X. The length in the second direction D2 of the terminal 31 according to examples 1 and 2 is the same as the length in the second direction D2 of the terminal 31X.

[0081] The terminal 31 according to Example 1 has a width Wa1 (see FIG. 9) of 0.145 mm and a width Wa2 (see FIG. 8) of 0.185 mm. A bump 33A having a height Z1 (see FIG. 9) of 0.160 mm at the center O was formed on the terminal 31.

[0082] The terminal 31 according to Example 2 has a width Wa1 of 0.145 mm and a width Wa2 of 0.215 mm. A bump 33A having a height Z1 at the center O of 0.151 mm was formed on this terminal 31.

[0083] The terminal 31X according to the comparative example has a width of 0.185 mm at any position in the second direction D2. A bump 33X having a height Z1 at the center O of 0.163 mm was formed on this terminal 31X.

[0084] The width Wb1 (see FIG. 9) at the center O of the bump 33A according to Example 1 was 0.205 mm, and the width Wb2 (see FIG. 11) at the center O of the bump 33A (bump 33Af) after planarization was 0.303 mm. The width Wb1 at the center O of the bump 33A according to Example 2 was 0.193 mm, and the width Wb2 at the center O of the bump 33A (bump 33Af) after planarization was 0.275 mm.

[0085] On the other hand, the width Wb1 at the center O of the bump 33X according to the comparative example was 0.229 mm, and the width Wb2 at the center O of the bump 33X after planarization was 0.337 mm.

[0086] The width Wb1 of the bumps 33A according to Examples 1 and 2 is smaller than the width Wb1 of the bumps 33X according to the comparative example. Furthermore, the width Wb2 of the bumps 33A (bumps 33Af) according to Examples 1 and 2 is smaller than the width Wb2 of the bumps 33X according to the comparative example. From these facts, it can be seen that the risk of short-circuiting between adjacent bumps 33A is reduced in the terminals 31 and bumps 33A according to Examples 1 and 2 compared to the comparative example, both before and after planarization.

[0087] In both Examples 1 and 2, it was possible to form bumps 33A with good shapes that did not fall off the terminals 31. Furthermore, when the bumps 33A were connected to the bumps 33B of other terminals 32 by the connection method of this embodiment, it was possible to form connection members 33 with good shapes.

[0088] Note that terminal 31 and bump 33A, terminal 32 and bump 33B, terminal 41 and bump 43A, and terminal 42 and bump 43B do not all need to have the same structure. For example, terminals 31, 32, 41, and 42 may have different widths Wa1 and Wa2, respectively. Furthermore, bumps 33A, 33B, 43A, and 43B before planarization may have different widths Wb1 and heights Z1, respectively, and bumps 33A, 33B, 43A, and 43B after planarization may have different widths Wb2 and heights Z2, respectively.

[0089] In the first embodiment, the terminal 31 and bump 33A, the terminal 32 and bump 33B, the terminal 41 and bump 43A, and the terminal 42 and bump 43B all have the structures described with reference to FIGS. 7 to 9. However, this structure does not necessarily need to be applied to all of these combinations of terminals and bumps. Several embodiments based on this viewpoint are disclosed below. In each embodiment, configurations not specifically mentioned are the same as those in the first embodiment.

[0090] [Second embodiment] In the second embodiment, the terminals 31 and bumps 33A of the suspension 10 have the structures described with reference to Figures 7 to 9. On the other hand, the terminals 32 and bumps 33B of the flexible printed circuit board 11 do not have the structures described with reference to Figures 7 to 9. For example, the terminals 32 have a rectangular shape with a constant width in the first direction D1. Even with this configuration, the same effects as in the first embodiment can be obtained with respect to the terminals 31 and bumps 33A.

[0091] [Third embodiment] In the third embodiment, the terminals 41 and bumps 43A of the suspension 10 have the structures described with reference to Figures 7 to 9. On the other hand, the terminals 42 and bumps 43B of the slider 12 do not have the structures described with reference to Figures 7 to 9. For example, the terminals 42 have a rectangular shape with a constant width in the first direction D1. Even with this configuration, the same effects as in the first embodiment can be obtained with respect to the terminals 41 and bumps 43A.

[0092] [Fourth embodiment] In the fourth embodiment, the terminals 31 and bumps 33A of the suspension 10 do not have the structure described with reference to Figures 7 to 9. On the other hand, the terminals 32 and bumps 33B of the flexible printed circuit board 11 have the structure described with reference to Figures 7 to 9. For example, the terminals 31 have a rectangular shape with a constant width in the first direction D1. Even with this configuration, the same effects as in the first embodiment can be obtained with respect to the terminals 32 and bumps 33B.

[0093] [Fifth embodiment] In the fifth embodiment, the terminals 41 and bumps 43A of the suspension 10 do not have the structure described with reference to Figures 7 to 9. On the other hand, the terminals 42 and bumps 43B of the slider 12 have the structure described with reference to Figures 7 to 9. For example, the terminals 41 have a rectangular shape with a constant width in the first direction D1. Even with this configuration, the same effects as in the first embodiment can be obtained with respect to the terminals 42 and bumps 43B.

[0094] [Variations] The shape of terminal 31 shown in FIG. 7 is merely one example of a shape that can be applied to terminals 31, 32, 41, and 42. Various other shapes can be applied to terminals 31, 32, 41, and 42. First to third modified examples of the shape of terminal 31 are disclosed below. The shapes of terminal 31 according to these modified examples can also be applied to terminals 32, 41, and 42.

[0095] 15 is a schematic plan view of a terminal 31 according to a first modified example. In the first modified example, a recess R is provided on the second side S2, and no recess R is provided on the first side S1. Even with this configuration, a narrow portion NP and a wide portion WP are formed in the terminal 31. Therefore, the same effects as those of the first embodiment can be obtained.

[0096] 16 is a schematic plan view of a terminal 31 according to a second modification. In the second modification, a recess R is provided on each of the first side S1, the second side S2, and the fourth side S4. By forming a recess R on the fourth side S4 in this way, the height Z1 of the bump 33A at the center O can be further increased.

[0097] 17 is a schematic plan view of a terminal 31 according to a third modified example. In the third modified example, the terminal 31 has an outer diameter that follows the circle CR indicated by the dashed line. Furthermore, the outer shape of the terminal 31 has four recesses R recessed toward the center O. The recesses R are, for example, semicircular. Even when the terminal 31 has such a shape, the height Z1 of the bump 33A at the center O can be increased.

[0098] The cross-sectional structures of the terminals 31, 32, 41, and 42 are not limited to the examples shown in FIGS. 18 is a schematic cross-sectional view showing another structure that can be applied to the terminal 31. The structure of the terminal 31 shown in this figure can also be applied to the terminals 32, 41, and .

[0099] 18, a conductive layer 310 is formed on the surface 23a of the pad portion 23, and the conductive layer 310 is covered with a plating layer 311. Furthermore, an insulating layer 320 is formed on the plating layer 311. The insulating layer 320 has an opening OP. The plating layer 311 is exposed from the insulating layer 320 through the opening OP. This exposed area corresponds to the terminal 31.

[0100] In this way, the same shapes as those of the terminals 31 in the above-described embodiments can be applied to the shape of the terminals 31 determined by the openings OP in the insulating layer 320. This makes it possible to obtain the same effects as those of the above-described embodiments.

[0101] The scope of the present invention is not limited to the configurations disclosed in the respective embodiments and modifications. The present invention can be implemented by modifying the configurations disclosed in the respective embodiments and modifications in various ways. [Explanation of symbols]

[0102] 1... disk device, 10... suspension, 11... flexible printed circuit board, 12... slider, 31, 32, 41, 42... terminals, 33, 43... connecting members, 33A, 33B, 43A, 43B... bumps, R... recesses.

Claims

1. A load beam; a flexure superposed on the load beam; a first terminal provided on the flexure; a first bump disposed on an upper surface of the first terminal; Equipped with The first terminal is a narrow portion having a first width in a first direction and including a center of the first terminal; a wide portion having a second width greater than the first width in the first direction and aligned with the narrow portion in a second direction intersecting the first direction; Including, the first bump has a first height at the center relative to a lower surface of the first terminal; The first height is greater than the first width. Suspension for disk drives.

2. the first terminal has a first side and a second side that intersect with the first direction; At least one of the first side and the second side includes a recess recessed in the first direction in the narrow portion.

2. The disk drive suspension according to claim 1.

3. the first terminal includes a pair of the wide portions, The narrow portion is located between the pair of wide portions in the second direction.

2. The disk drive suspension according to claim 1.

4. The first height is less than the second width.

4. The disk drive suspension according to claim 1.

5. 10. A method for electrically connecting the disk drive suspension according to claim 1 to an electronic component including a second terminal and a second bump disposed on an upper surface of the second terminal, comprising: planarizing the first bump; aligning the suspension and the electronic component so that the first bump and the second bump are adjacent to each other and a first plane including an upper surface of the first terminal and a second plane including an upper surface of the second terminal intersect with each other; connecting the first bump and the second bump by melting the first bump and the second bump; Connection methods including.

6. the flattened first bump has a second height at the center relative to the lower surface of the first terminal; The second height is at least 15% smaller than the first height. The connection method according to claim 5.

7. The second height is less than the first width. The connection method according to claim 6.

8. the electronic component is a flexible printed circuit board or a slider constituting a magnetic head; The connection method according to any one of claims 5 to 7.

9. An electronic component electrically connected to a disk drive suspension, A second terminal; a second bump disposed on an upper surface of the second terminal; Equipped with The second terminal is a narrow portion having a first width in a first direction and including a center of the second terminal; a wide portion having a second width greater than the first width in the first direction and aligned with the narrow portion in a second direction intersecting the first direction; Including, the second bump has a first height at the center relative to a lower surface of the second terminal; The first height is greater than the first width. Electronic components.

10. the second terminal has a first side and a second side that intersect with the first direction, At least one of the first side and the second side includes a recess recessed in the first direction in the narrow portion. The electronic component according to claim 9.

11. the second terminal includes a pair of the wide portions, The narrow portion is located between the pair of wide portions in the second direction. The electronic component according to claim 9.

12. The first height is less than the second width. The electronic component according to any one of claims 9 to 11.

13. 10. A connection method for electrically connecting a disk drive suspension including a first terminal and a first bump disposed on an upper surface of the first terminal to the electronic component according to claim 9, comprising: planarizing the second bump; aligning the suspension and the electronic component so that the first bump and the second bump are adjacent to each other and a first plane including an upper surface of the first terminal and a second plane including an upper surface of the second terminal intersect with each other; connecting the first bump and the second bump by melting the first bump and the second bump; Connection methods including.

14. the flattened second bump has a second height at the center relative to the lower surface of the second terminal; The second height is at least 15% smaller than the first height. The connection method according to claim 13.

15. The second height is less than the first width. The connection method according to claim 14.

16. the electronic component is a flexible printed circuit board or a slider constituting a magnetic head; 16. The connection method according to any one of claims 13 to 15.

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