JP2013137852A - Substrate for suspension, suspension, suspension with head and hard disk drive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate for suspension that can improve connection reliability with an actuator element connected to the substrate for suspension through a conductive adhesive.SOLUTION: A substrate for suspension 1 includes a head part 2a where a head slider 52 is implemented, a tail part 2b connected to an external connection substrate 71, and an element connection part 3 connected to an actuator element 44 through a conductive adhesive. The element connection part 3 is coupled to a substrate body 2 through a linear leading-out part 4. The leading-out part 4 extends, in a plan view, in a direction orthogonal to the extension/contraction direction of the actuator element 44.

Description

  The present invention relates to a suspension board, a suspension, a suspension with a head, and a hard disk drive, and in particular, for a suspension that can improve connection reliability with an actuator element connected to the suspension board via a conductive adhesive. The present invention relates to a substrate, a suspension, a suspension with a head, and a hard disk drive.

  In general, a hard disk drive (HDD) includes a suspension board on which a magnetic head slider for writing and reading data to and from a disk storing data is mounted. The suspension substrate is formed to extend from a head region on which the magnetic head slider is mounted to a tail region connected to an FPC substrate (flexible printed circuit board), and a metal support layer and an insulating layer on the metal support layer And a wiring layer having a plurality of wirings stacked via each other, and by writing an electric signal through each wiring, data is written to or read from the disk.

  In such a hard disk drive, in order to move the magnetic head slider to a desired data track on the disk, a VCM actuator (voice coil motor) that rotates an actuator arm that supports the magnetic head slider is controlled by a servo control system. doing.

  In recent years, there has been an increasing demand for an increase in disk capacity. In order to meet this demand, the density of the disk is increased and the width of the track is reduced. For this reason, it may be difficult to accurately align the magnetic head slider to a desired track by the VCM actuator.

  In order to cope with this, a dual actuator type suspension is known in which a VCM actuator and a PZT microactuator (Dual Stage Actuator: DSA) cooperate to move a magnetic head slider to a desired track (for example, , See Patent Document 1). This PZT microactuator is constituted by a piezoelectric element such as a piezoelectric element made of PZT (lead zirconate titanate), and expands and contracts when a voltage is applied to move the magnetic head slider minutely. In such a dual actuator type suspension, the VCM actuator roughly adjusts the position of the magnetic head slider, and the PZT microactuator finely adjusts the position of the magnetic head slider. In this way, the magnetic head slider is aligned with a desired track quickly and accurately.

  In the suspension substrate shown in Patent Document 1, an element connecting portion for supplying power to the piezo element is connected to a substrate body extending from the tail portion side via a substantially linear lead portion.

JP 2010-86649 A

  However, the lead-out portion shown in Patent Document 1 extends in a direction inclined in the expansion / contraction direction of the piezo element. As a result, when the piezo element expands and contracts, stress in the longitudinal direction is applied to the drawer portion. By the way, the longitudinal direction of the lead-out portion is significantly higher in rigidity than the width direction. For this reason, the lead portion repels stress applied in the longitudinal direction, and the element connecting portion is prevented from following the expansion and contraction of the piezo element. In this case, stress is applied to the conductive adhesive portion made of the conductive adhesive that joins the element connecting portion and the piezoelectric element, and the conductive adhesive portion is peeled off from at least one of the element connecting portion and the piezoelectric element. A possibility arises. For this reason, a problem may arise in the connection reliability of an element connection part and a piezoelectric element.

  The present invention has been made in consideration of such points, and the suspension substrate and the suspension capable of improving the connection reliability with the actuator element connected to the suspension substrate via the conductive adhesive. An object is to provide a suspension with a head and a hard disk drive.

  The present invention is a suspension substrate on which a head slider is mounted, and the head slider is mounted on a suspension substrate connected to an external connection substrate and connected to an actuator element via a conductive adhesive. A substrate body having a head portion and a tail portion to which the external connection substrate is connected, and connected to the substrate body via a linear lead portion, and connected to the actuator element via the conductive adhesive The suspension substrate is characterized in that the drawing portion extends in a direction orthogonal to the expansion / contraction direction of the actuator element in plan view.

  In the suspension substrate described above, the element connection portion may be disposed closer to the tail portion than the central portion of the actuator element in plan view.

  The present invention includes a base plate having an accommodation opening, the above-described suspension substrate attached to the base plate via a load beam, and accommodated in the accommodation opening of the base plate and joined to the base plate. And the actuator element joined to a surface of the load beam on the base plate side, the load beam having an exposed opening for exposing a part of the actuator element, and the element of the suspension substrate. The connecting portion provides a suspension characterized in that the connecting portion is connected to the actuator element through the exposed opening of the load beam using the conductive adhesive.

  In the suspension described above, the element connection portion may be arranged on the tail portion side from the central portion of the actuator element in a plan view.

  In the suspension described above, the exposed opening of the load beam is defined by a pair of exposed opening edges extending in a direction perpendicular to the expansion / contraction direction of the actuator element. A concave portion that opens toward the element connecting portion in a plan view may be provided on the edge of the exposed opening on the tail portion side.

  Further, in the above-described suspension, the actuator element has a plan view of the load beam so that the expansion / contraction direction of the actuator element intersects the longitudinal axis of the load beam on the head portion side of the suspension substrate. It may be arranged so as to be inclined with respect to the longitudinal axis.

  The present invention provides a suspension with a head, comprising the above-described suspension and the head slider mounted on the suspension.

  The present invention provides a hard disk drive comprising the aforementioned suspension with a head.

  ADVANTAGE OF THE INVENTION According to this invention, connection reliability with the actuator element connected via a conductive adhesive can be improved.

FIG. 1 is a plan view showing an example of a suspension according to an embodiment of the present invention. FIG. 2 is a plan view showing the details of part A of FIG. FIG. 3 is a rear view of FIG. 4 is a cross-sectional view taken along line BB in FIG. FIG. 5 is a cross-sectional view taken along line CC in FIG. FIG. 6 is a perspective view showing an example of a piezoelectric element in the suspension of FIG. FIG. 7 is a plan view showing an example of a suspension with a head according to the embodiment of the present invention. FIG. 8 is a perspective view showing an example of the hard disk drive in the embodiment of the present invention. FIG. 9 is a plan view showing a modified example (modified example 1) of the details of the portion A in FIG. FIG. 10 is a plan view showing a modified example (modified example 2) of the details of the portion A in FIG.

  A suspension substrate, a suspension, a suspension with a head, and a hard disk drive according to an embodiment of the present invention will be described with reference to FIGS.

  First, the suspension 41 according to the present embodiment will be described with reference to FIG. As shown in FIG. 1, the suspension 41 is connected to a base plate 42, a suspension substrate 1 attached to the base plate 42 via a load beam 43, and a pair of element connecting portions 3 (described later) of the suspension substrate 1. And a pair of rectangular piezo elements (actuator elements) 44. Of these, the suspension substrate 1 is mounted with a head slider 52 (see FIG. 7), which will be described later, connected to the FPC board 71 (external connection board, flexible printed board, see FIG. 7), and electrically conductive to the piezo element 44. It is connected via an adhesive (for example, silver paste).

  That is, as shown in FIG. 1, the suspension substrate 1 is composed of a substrate body 2 and a pair of element connecting portions 3 disposed on both sides of the substrate body 2, and the substrate body 2 is connected to the substrate body 2 via the drawing portion 4. And a pair of element connection portions 3 connected to the piezo element 44 via a conductive adhesive. Among these, the substrate body 2 has a head portion 2a on which the head slider 52 is mounted and a tail portion 2b to which the FPC board 71 is connected. The head part 2a is provided with a plurality of head terminals 5 connected to the head slider 52, and the tail part 2b is provided with a plurality of tail terminals (external connection board terminals) 6 connected to the FPC board 71. The head terminal 5 and the tail terminal 6 are connected to each other via a plurality of wires 13 to be described later.

  By the way, as shown in FIGS. 4 and 5, the suspension substrate 1 includes an insulating layer 10, a metal support layer 11 provided on the surface (one surface) of the insulating layer 10 on the piezoelectric element 44 side, and an insulating layer 10. And a wiring layer 12 having a plurality of wirings 13 provided on the other surface of the layer 10. A protective layer 20 that covers the wiring layer 12 is provided on the insulating layer 10. In FIGS. 1 and 2, the protective layer 20 is omitted for the sake of clarity.

  As shown in FIG. 2, each of the pair of element connection portions 3 is formed in a circular shape in plan view. Each element connecting portion 3 has a circular element connecting terminal 16 that is electrically connected to the piezo element 44 via a conductive adhesive. Each element connection terminal 16 is connected to one wiring 13 among the plurality of wirings 13 of the wiring layer 12 in the substrate body 2. The element connection terminal 16 is made of the same material as each wiring 13 and has substantially the same thickness as each wiring 13, and forms the wiring layer 12 together with the head terminal 5, tail terminal 6 and wiring 13. ing. In the present embodiment, the element connecting portion 3 is disposed at a substantially central portion of the piezo element 44 in plan view.

  As shown in FIGS. 4 and 5, the metal support layer 11 has a ring-shaped frame portion 17 provided in each element connection portion 3. The frame portion 17 is separated from a portion constituting the metal support layer 11 in the substrate body 2 and forms a metal support layer injection hole 32 penetrating the metal support layer 11. The insulating layer 10 is provided with an insulating layer injection hole 33 penetrating the insulating layer 10 corresponding to the metal support layer injection hole 32. In this way, the surface on the piezoelectric element 44 side of the element connection terminal 16 of the wiring layer 12 is exposed by the metal support layer injection hole 32 and the insulating layer injection hole 33. Further, nickel (Ni) plating and gold (Au) plating are sequentially applied to the surface exposed in the insulating layer injection hole 33 of the element connection terminal 16 to form the plating layer 15. This prevents the exposed surface of the element connection terminal 16 from being corroded. In addition, it is preferable that the thickness of this plating layer 15 is 0.1 micrometer-4.0 micrometers.

  As shown in FIG. 2, the substrate body 2 and each element connection portion 3 are connected via a linear lead portion 4. In this way, the element connection terminal 16 of each element connection portion 3 is connected to the wiring 13 extending from the tail terminal 6 of the substrate body 2 through the corresponding lead portion 4. As shown in FIG. 4, each lead portion 4 has a laminated structure in which the insulating layer 10, the wiring layer 12, and the protective layer 20 are laminated without including a portion constituting the metal support layer 11. (See FIG. 4), which is more flexible than the substrate body 2.

  As shown in FIGS. 1 and 2, each drawing portion 4 extends in a direction orthogonal to the expansion / contraction direction of the piezoelectric element 44 (arrow P in FIGS. 1 and 7) in plan view. Specifically, the drawing portion 4 is orthogonal to a side edge (side edge on the longitudinal axis X side) 44c along the expansion / contraction direction of the rectangular piezo element 44 in plan view. That is, in the present embodiment, the piezo element 44 is arranged along the longitudinal axis (X) of the load beam 43, and its expansion / contraction direction is parallel to the longitudinal axis (X). 4 is formed to extend in a direction perpendicular to the longitudinal axis (X). More specifically, in each lead portion 4, the insulating layer 10, the wiring 13, and the protective layer 20 are linearly formed so as to extend in a direction orthogonal to the expansion / contraction direction of the piezo element 44.

  As shown in FIG. 1, the substrate body 2 is provided with two jig holes 25 for alignment with the load beam 43 when the suspension substrate 1 is attached to the load beam 43. . Each jig hole 25 is disposed on the longitudinal axis (X). That is, the longitudinal axis (X) passes through each jig hole 25. As shown in FIG. 2, the substrate body 2 is provided with a joint portion 35 for joining the suspension substrate 1 to the load beam 43. The joint 35 is welded to join the suspension substrate 1 and the load beam 43.

  Next, materials constituting each layer of the suspension substrate 1 will be described in detail.

  The material of the insulating layer 10 is not particularly limited as long as it is a material having a desired insulating property. For example, it is preferable to use polyimide (PI). Note that the material of the insulating layer 10 can be a photosensitive material or a non-photosensitive material. The thickness of the insulating layer 10 is preferably 5 μm to 30 μm, particularly 8 μm to 10 μm. As a result, it is possible to ensure the insulation performance between the metal support layer 11 and each wiring 13 and to prevent the rigidity of the suspension substrate 1 as a whole from being lost.

  Each wiring 13 is configured as a conductor for transmitting an electrical signal, and the material of each wiring 13 is not particularly limited as long as it has a desired conductivity, but copper (Cu) Is preferably used. In addition to copper, any material having electrical characteristics similar to pure copper can be used. Here, it is preferable that the thickness of each wiring 13 is, for example, 1 μm to 18 μm, particularly 9 μm to 12 μm. As a result, it is possible to ensure the transmission characteristics of each wiring 13 and to prevent the flexibility of the suspension substrate 1 as a whole from being lost. The head terminal 5, tail terminal 6 and element connection terminal 16 are made of the same material and the same thickness as each wiring 13.

  The material of the metal support layer 11 is not particularly limited as long as it has desired conductivity, elasticity, and strength. For example, stainless steel, aluminum, beryllium copper, or other copper alloys are used. It is preferable to use stainless steel. The thickness of the metal support layer 11 is preferably 10 μm to 30 μm, more preferably 15 μm to 20 μm. As a result, the conductivity, rigidity, and elasticity of the metal support layer 11 can be ensured.

  As a material of the protective layer 20, it is preferable to use a resin material such as polyimide. The material of the protective layer 20 can be a photosensitive material or a non-photosensitive material. The thickness of the protective layer 20 is preferably 2 μm to 30 μm.

  Next, the base plate 42 and the load beam 43 according to this embodiment will be described with reference to FIGS.

  The base plate 42 is made of stainless steel, and, as shown in FIG. 3, a head side plate 42a disposed on the head portion 2a side of the suspension substrate 1, a tail side plate 42b disposed on the tail portion 2b side, A flexible portion 42c connecting the head side plate 42a and the tail side plate 42b. The base plate 42 has an accommodation opening 42 d for accommodating the piezo element 44. The accommodation opening 42d is formed by a head side plate 42a, a tail side plate 42b, and a flexible portion 42c.

  The load beam 43 is made of stainless steel like the base plate 42, and is arranged on the head side beam 43a disposed on the head portion 2a side of the suspension substrate 1 and on the tail portion 2b side as shown in FIG. The tail side beam 43b and the flexible part 43c which connected the head side beam 43a and the tail side beam 43b are provided. The load beam 43 has an exposed opening 43 d that exposes the surface of the piezo element 44 on the element connecting portion 3 side. The exposed opening 43d is formed by a head side beam 43a, a tail side beam 43b, and a flexible portion 43c.

  A piezo element 44 is joined to the base plate 42 and the load beam 43 thus formed. That is, as shown in FIG. 5, the piezo element 44 is accommodated in the accommodation opening 42 d of the base plate 42, joined to the base plate 42, and joined to the surface of the load beam 43 on the base plate 42 side. As shown in FIG. 4, the element connecting portion 3 of the suspension substrate 1 is connected to the piezo element 44 through the exposed opening 43 d of the load beam 43.

  The load beam 43 is provided with a beam jig hole (not shown) corresponding to each jig hole 25 of the suspension substrate 1, and when the load beam 43 is attached to the suspension substrate 1. The suspension substrate 1 and the load beam 43 can be aligned. The jig hole of the load beam 43 is disposed on the longitudinal axis (X). The load beam 43 and the suspension substrate 1 are fixed by welding. In this case, welding is performed on the joint 35 of the metal support layer 11 to form a weld 45.

  The piezo element 44 is configured as a piezoelectric element that expands and contracts when a voltage is applied, and is for moving the head slider 52 in the sway direction (the turning direction, arrow Q in FIGS. 1 and 7). As shown in FIG. 6, each piezo element 44 is interposed between a pair of electrodes 44a facing each other and a pair of electrodes 44a, and a piezoelectric material portion 44b made of a piezoelectric ceramic such as PZT (lead zirconate titanate), for example. And have. The piezoelectric material portions 44b of the pair of piezo elements 44 are formed to have polarization directions different from each other by 180 °. When a predetermined voltage is applied, one piezo element 44 contracts and the other piezo element 44 44 extends. As shown in FIGS. 1 and 2, such a piezo element 44 is disposed along the longitudinal axis (X) of the load beam 43, and its expansion / contraction direction is parallel to the longitudinal axis (X). It has become. The piezo elements 44 are arranged symmetrically with respect to the longitudinal axis (X) so that the expansion and contraction of each piezo element 44 is evenly transmitted to the head slider 52.

  As shown in FIG. 5, each piezo element 44 is joined to the base plate 42 and the load beam 43 via a nonconductive adhesive portion 46 made of a nonconductive adhesive. As shown in FIGS. 3 and 5, one electrode 44a of the piezo element 44 (on the side opposite to the suspension substrate 1) is electrically connected to the base plate 42 via a first conductive adhesive portion 47 made of a conductive adhesive. Connected. Further, the other electrode 44a (the suspension substrate 1 side) of the piezo element 44 is joined to the element connecting portion 3 via a second conductive adhesive portion 48 made of a conductive adhesive, as shown in FIG. And electrically connected. That is, a conductive adhesive is injected into the metal support layer injection hole 32 and the insulating layer injection hole 33 in the element connection portion 3 to form the second conductive adhesive portion 48, and the piezo element 44 is connected to the second conductive adhesive portion 48. The other electrode 44 a of the piezo element 44 is electrically connected to the element connection terminal 16 of the wiring layer 12 via the second conductive adhesive portion 48. .

  Next, referring to FIG. 7, the suspension with head 51 in the present embodiment will be described. A suspension 51 with a head shown in FIG. 7 has the above-described suspension 41 and a head slider 52 connected to the head terminal 5 of the suspension substrate 1.

  Next, the hard disk drive 61 in the present embodiment will be described with reference to FIG. A hard disk drive 61 shown in FIG. 8 is provided with a case 62, a disk 63 that is rotatably attached to the case 62, stores data, a spindle motor 64 that rotates the disk 63, and a desired flying height on the disk 63. And a suspension 51 with a head including a head slider 52 that writes and reads data to and from the disk 63. Among them, the suspension with head 51 is attached to the case 62 so as to be movable, and the voice coil motor 65 for moving the head slider 52 of the suspension with head 51 along the disk 63 is attached to the case 62. Yes. The suspension 51 with the head is attached to the voice coil motor 65 via the arm 66 and connected to an FPC board 71 (see FIG. 7) connected to a control unit (not shown) that controls the hard disk drive 61. ing. In this way, an electrical signal is transmitted between the control unit and the head slider 52 via the suspension board 1 and the FPC board 71.

  Next, the case where the suspension substrate 1 according to the present embodiment is manufactured by the subtractive method will be described.

  First, a laminated body (not shown) having an insulating layer 10, a metal support layer 11 provided on one surface of the insulating layer 10, and a wiring layer 12 provided on the other surface of the insulating layer 10 is formed. prepare. Subsequently, the wiring layer 12 is etched into a desired shape, and the wiring 13, the head terminal 5, the tail terminal 6, and the element connection terminal 16 are formed. At this time, the metal support layer 11 is similarly etched to form the metal support layer injection hole 32. Next, a protective layer 20 that covers each wiring 13 is formed on the insulating layer 10. Subsequently, the insulating layer 10 is etched into a desired shape, and an insulating layer injection hole 33 is formed in the insulating layer 10. Thereafter, the metal support layer 11 is etched and contoured to form the frame body portion 17. Thus, the suspension substrate 1 in the present embodiment is obtained. The suspension substrate 1 can also be manufactured by an additive method.

  Next, a method for manufacturing the suspension 41 in the present embodiment will be described.

  First, the base plate 42 and the load beam 43 are prepared, and the above-described suspension substrate 1 is prepared.

  Next, the suspension substrate 1 is attached to the base plate 42 via the load beam 43 by welding. In this case, first, the load beam 43 is fixed to the base plate 42 by welding, then, a beam jig hole (not shown) provided in the load beam 43 and a jig hole 25 provided in the suspension substrate 1. As a result, the alignment of the load beam 43 and the suspension substrate 1 is performed. Thereafter, welding is performed on the joint portion 35 of the metal support layer 11 of the suspension substrate 1 to form a weld portion 45, and the load beam 43 and the suspension substrate 1 are joined and fixed to each other.

  Next, the piezo element 44 is bonded to the base plate 42 and the load beam 43 using an adhesive, and is connected to the element connecting portion 3 of the suspension substrate 1. In this case, first, the piezo element 44 is bonded to the base plate 42 and the load beam 43 via the non-conductive adhesive portion 46. Next, a conductive adhesive is applied to form a first conductive adhesive portion 47, and an electrode 44 a on one side (opposite side of the suspension substrate 1) of the piezo element 44 is formed via the first conductive adhesive portion 47. The base plate 42 is electrically connected via a conductive adhesive.

  The other electrode 44a (suspension substrate 1 side) of the piezo element 44 is joined and electrically connected to the element connection portion 3 of the suspension substrate 1 via the second conductive adhesive portion 48. (See FIG. 4). A conductive adhesive is previously injected into the insulating layer injection hole 33 and the metal support layer injection hole 32 of the suspension substrate 1, and when the piezoelectric element 44 is joined to the base plate 42 and the load beam 43, the element connection terminal 16. Is joined to and electrically connected to one electrode 44a of the piezo element 44.

  In this way, the suspension 41 according to the present embodiment is obtained.

  A head slider 52 is connected to the head terminal 5 of the suspension 41 to obtain a suspension with head 51 shown in FIG. Further, the suspension 51 with the head is attached to the case 62 of the hard disk drive 61 to obtain the hard disk drive 61 shown in FIG.

  When writing and reading data in the hard disk drive 61 shown in FIG. 8, the head slider 52 of the suspension with head 51 is moved along the disk 63 by the voice coil motor 65 and is rotated by the spindle motor 64. Keep close to the desired flying height. As a result, data is exchanged between the head slider 52 and the disk 63. During this time, an electrical signal is transmitted between the control unit (not shown) connected to the FPC board 71 and the head slider 52 via the suspension board 1 and the FPC board 71. Such an electrical signal is transmitted between the head terminal 5 and the tail terminal 6 through the wirings 13 in the suspension board 1.

  When moving the head slider 52, the voice coil motor 65 roughly adjusts the position of the head slider 52, and the piezo element 44 finely adjusts the position of the head slider 52. That is, by applying a predetermined voltage to the electrode 44a of the piezo element 44 on the element connecting portion 3 side of the suspension substrate 1, one piezo element 44 contracts in the direction along the longitudinal axis (X). At the same time, the other piezo element 44 extends (see FIG. 7). In this case, the flexible portion 52b of the base plate 42 and the flexible portion 43c of the load beam 43 are elastically deformed, and the head slider 52 located on the tip side of the load beam 43 can move in the sway direction (turning direction). . In this way, the head slider 52 can be quickly and accurately aligned with a desired track of the disk 63. When the piezo element 44 expands and contracts, the lead portion 4 that connects the substrate body 2 and the element connection portion 3 extends in a direction orthogonal to the stretch direction of the piezo element 44, so that the lead portion 4 extends in the longitudinal direction of the lead portion 4. The stress is suppressed from being applied, and the element connecting portion 3 can smoothly follow the expansion and contraction of the piezo element 44.

  Thus, according to the present embodiment, the lead portion 4 that connects the substrate body 2 and the element connection portion 3 extends in a direction orthogonal to the expansion / contraction direction of the piezoelectric element 44 in plan view. Thereby, when the piezo element 44 expands and contracts, it is possible to suppress the stress in the longitudinal direction from being applied to the extraction portion 4. That is, it is possible to suppress stress from being applied in the longitudinal direction where the rigidity is remarkably higher than that in the width direction of the lead-out portion 4. Therefore, the element connecting portion 3 can smoothly follow the expansion and contraction of the piezo element 44, and stress is applied to the second conductive adhesive portion 48 that joins the element connecting portion 3 and the piezo element 44. This can be suppressed. As a result, the second conductive adhesive portion 48 is prevented from being peeled off from the element connecting portion 3 and from the piezoelectric element 44, and the piezoelectric element 44 connected via the conductive adhesive is Bonding reliability with the element connection portion 3 can be improved.

  In the present embodiment, the example in which the element connecting portion 3 is disposed at the substantially central portion of the piezo element 44 has been described. However, the present invention is not limited to this, and as shown in FIG. 9, the element connection portion 3 may be disposed on the tail portion 2 b side from the central portion of the piezo element 44 in plan view. That is, when the piezo element 44 is expanded and contracted, the end edge on the tail portion 2b side of the piezo element 44 acts as a fixed side of the piezo element 44. The displacement due to expansion and contraction of the piezo element 44 is smaller than that of the central portion and the portion on the head portion 2b side. For this reason, the stress applied to the second conductive adhesive portion 48 between the piezo element 44 and the element connecting portion 3 can be further reduced. Even in this case, the element connecting portion 3 is disposed on the piezo element 44 as a whole, and the conductive adhesive that connects the element connecting portion 3 and the piezo element 44 protrudes from the piezo element 44. It is preferable to be disposed at a position where prevention is possible.

  Further, in the first modification shown in FIG. 9, the load beam 43 is provided with a recess 43 e. In other words, the exposed opening 43d of the load beam 43 is defined by a pair of exposed opening edges 43f extending in a direction perpendicular to the expansion / contraction direction of the piezo element 44, and the tail portion 2b of the pair of exposed opening edges 43f is defined. A concave portion 43e that opens toward the element connection portion 3 in a plan view is provided in the exposed opening edge 43f on the side.

  According to the first modification shown in FIG. 9, the element connecting portion 3 is connected to a portion of the piezo element 44 where the displacement due to expansion and contraction of the piezo element 44 is small, and the element connecting portion 3 and the piezo element 44 are joined. It is possible to further suppress the stress due to the expansion and contraction of the piezo element 44 from being applied to the second conductive adhesive portion 48. For this reason, it is possible to prevent the second conductive adhesive portion 48 from being peeled off from the element connecting portion 3 and from the piezoelectric element 44, and to improve the bonding reliability between the piezoelectric element 44 and the element connecting portion 3. Can be improved.

  In addition, according to the first modification, the load beam 43 is provided with the concave portion 43e, so that the element connecting portion 3 arranged on the tail portion 2b side, the element connecting portion 3 and the piezo element 44 are connected. The two conductive adhesive portions 48 can be prevented from coming into contact with the load beam 43, and the element connecting portion 3 can be prevented from being short-circuited to the load beam 43.

  In the present embodiment, the example in which the piezo element 44 is arranged along the longitudinal axis (X) and the expansion / contraction direction thereof is parallel to the longitudinal axis (X) has been described. However, the present invention is not limited to this, and as shown in FIG. 10, the piezoelectric element 44 extends and contracts so that the piezoelectric element 44 crosses the longitudinal axis (X) on the head portion 2 side of the suspension substrate 1. The element 44 may be disposed to be inclined with respect to the longitudinal axis (X) in plan view. In this case, in particular, the expansion / contraction direction of the piezo element 44 is preferably directed to the head slider 52. According to the second modification shown in FIG. 10, the expansion / contraction direction of the piezo element 44 can be directed toward the head slider 52, and the expansion / contraction force of the piezo element 44 is lost and reduced until it is transmitted to the head slider 52. Therefore, the head slider 52 can be efficiently displaced in the sway direction. Also in this case, each drawing portion 4 extends in a direction orthogonal to the expansion / contraction direction of the piezo element 44 (arrow P in FIG. 10) in plan view.

  Further, in the present embodiment, as shown in FIG. 1, the suspension substrate 1 is connected to the pair of piezo elements 44 so that the pair of element connection portions 3 disposed on both sides of the substrate body 2 is provided. However, the present invention is not limited to this example, and the present invention is applied to a suspension substrate in which the element connection portion 3 is provided on one side of the substrate body 2 via the lead-out portion 4. It is also possible to do.

  As described above, the embodiments of the present invention have been described in detail. However, the suspension substrate, the suspension, the suspension with a head, and the hard disk drive according to the present invention are not limited to the above-described embodiments, and the gist of the present invention. Various modifications can be made without departing from the scope.

DESCRIPTION OF SYMBOLS 1 Suspension board | substrate 2 Board | substrate body 2a Head part 2b Tail part 3 Element connection part 4 Lead-out part 5 Head terminal 6 Tail terminal 10 Insulating layer 11 Metal support layer 12 Wiring layer 13 Wiring 15 Plating layer 16 Element connection terminal 17 Frame body part 20 Protective layer 25 Jig hole 32 Metal support layer injection hole 33 Insulating layer injection hole 35 Joint part 41 Suspension 42 Base plate 42a Head side plate 42b Tail side plate 42c Flexible part 42d Accommodating opening 43 Load beam 43a Head side beam 43b Tail side Beam 43c Flexible portion 43d Exposed opening 43e Recess 43f Exposed opening edge 44 Piezo element 44a Electrode 44b Piezoelectric material portion 44c Side edge 45 Welded portion 46 Nonconductive adhesive portion 47 First conductive adhesive portion 48 Second conductive adhesive Part 51 Suspension with head 52 Head slider 61 Disk drive 62 case 63 disk 64 spindle motor 65 voice coil motor 66 arm 71 FPC board

Claims (8)

In the suspension substrate on which the head slider is mounted, which is connected to the external connection substrate and connected to the actuator element via the conductive adhesive,
A substrate body having a head portion on which the head slider is mounted and a tail portion to which the external connection substrate is connected;
An element connecting portion coupled to the substrate body via a linear lead portion and connected to the actuator element via the conductive adhesive;
The suspension substrate according to claim 1, wherein the drawing portion extends in a direction orthogonal to the expansion / contraction direction of the actuator element in plan view.   The suspension substrate according to claim 1, wherein the element connection portion is disposed closer to the tail portion than a central portion of the actuator element in a plan view. A base plate having a receiving opening;
The suspension substrate according to claim 1 attached to the base plate via a load beam;
The actuator element housed in the housing opening of the base plate, joined to the base plate, and joined to the surface of the load beam on the base plate side;
The load beam has an exposed opening that exposes a part of the actuator element,
The suspension is characterized in that the element connecting portion of the suspension substrate is connected to the actuator element through the exposed opening of the load beam using the conductive adhesive.   The suspension according to claim 3, wherein the element connecting portion is disposed closer to the tail portion than a central portion of the actuator element in a plan view. The exposed opening of the load beam is defined by a pair of exposed opening edges extending in a direction perpendicular to the direction of expansion and contraction of the actuator element;
5. The recess according to claim 3, wherein a recessed portion that opens toward the element connection portion in a plan view is provided on the edge of the exposed opening on the tail portion side of the pair of exposed opening edges. The described suspension.   The actuator element extends relative to the longitudinal axis of the load beam in plan view so that the expansion / contraction direction of the actuator element intersects the longitudinal axis of the load beam on the head portion side of the suspension substrate. The suspension according to claim 3, wherein the suspension is inclined. The suspension according to any one of claims 3 to 6,
A suspension with a head, comprising: the head slider mounted on the suspension.   A hard disk drive comprising the suspension with a head according to claim 7.

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