Patent Publication Number: US-2023154489-A1

Title: Flexure of disk drive suspension and disk drive suspension

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2021-186538, filed Nov. 16, 2021, the entire contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a flexure of a disk drive suspension, and the disk drive suspension. 
     2. Description of the Related Art 
     A hard disk drive (HDD) is used in an information processing apparatus such as a personal computer. The hard disk drive comprises a magnetic disk that rotates about a spindle, a carriage that turns about a pivot, and the like. The carriage comprises an actuator arm, and turns about the pivot in a disk track width direction by a positioning motor such as a voice coil motor. 
     A disk drive suspension (hereafter referred to simply as a suspension) is attached to the actuator arm. The suspension includes a load beam, a flexure overlapping with the load beam, and the like. A slider, which constitutes a magnetic head, is provided on a gimbal portion formed near a distal end of the flexure. 
     The slider is provided with an element (transducer) for access such as reading or writing data. A head gimbal assembly is constituted by the load beam, the flexure, the slider, and the like. 
     In order to respond to higher recording densities of a disk, it is necessary. to further miniaturize the head gimbal assembly and enable the slider to be positioned on a recording surface of the disk with even higher precision. 
     Due to the strong demand for increased recording capacity of the hard disk drive for increased recording density, an increase in the number of magnetic disks that the hard disk drive comprises (so-called multi-disking) has been promoted. For example, JP 2020-129423 A discloses a disk drive that enables the number of magnetic disks installed as recording media to be increased. 
     To increase the number of magnetic disks, it is necessary not only to make magnetic disks thinner, but also to make intervals between the magnetic disks smaller. If the intervals between. the magnetic disks are made smaller, the risk that suspensions facing each other between the magnetic disks are brought into contact with each other may be increased. For this reason, thinning the suspensions is required. 
     However, there is still room. for various improvements in the thinning of suspensions. For example, it is sometimes difficult to make load beams thinner, which largely affects the spring load, suspension resonance, and the like. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention aims to provide a flexure of a disk drive suspension that can be made thinner and the disk drive suspension. 
     According to an embodiment, a flexure of a disk drive suspension comprises a metal base, and a wiring portion provided along the metal base. The wiring portion includes a. base insulating layer, a conductor layer overlapping with the base insulating layer, and a cover insulating layer over with the conductor layer, and the metal base includes a pair of first portions having side surfaces opposed to each other. 
     At least one of the base insulating layer and the cover insulating layer is in contact with the side surfaces between the pair of first portions, and the conductor layer does not overlap with the metal base in a direction of stacking the wiring portion. 
     The base insulating layer, the conductor layer, and the cover insulating layer are located between the side surfaces, and a thickness of the wiring portion may be less than or equal to a thickness of the pair of first portions. At least a part of the conductor layer may be buried in the base insulating layer. 
     The base insulating layer may be located between the side surfaces, and the conductor layer and the cover insulating layer may not be located between the side surfaces. The flexure further comprises an air layer, and the base insulating layer may be in contact with the air layer in between the side surfaces. 
     The flexure further comprises a support layer that supports the wiring portion and, in the stacking direction, the base insulating layer may have a first surface with which the conductor layer is in contact and a second surface opposed to the first surface, and the support layer may be in contact with the second surface. 
     The flexure further comprises a connection portion, and the conductor layer may include a plurality of lines arranged in a direction orthogonal to a direction of extension of the wiring portion, and the connection. portion. may be electrically connected to at least one of the plurality of lines. 
     According to of embodiment, a flexure of a disk drive suspension comprises a metal base, and a wiring portion provided along the metal base. The wiring portion includes a base insulating layer, a conductor layer overlapping with the base insulating layer, and a cover insulating layer overlapping with the conductor layer, and the metal base includes a pair of first portions having side surfaces opposed to each other and a second portion overlapping with the conductor layer and connected to the pair of first Portions. 
     At least one of the base insulating layer and the cover insulating layer is in contact with the side surfaces between the pair of first portions, and a thickness of the second. portion is smaller than a thickness of the first portions. The second portion may include an opening overlapping with the conductor layer. 
     According to yet another embodiment, a disk drive, suspension comprises a load beam, and the flexure over-lapping with the load beam. 
     According to this configuration, a flexure of a disk drive suspension that can be thinned and the disk drive suspension can be provided. 
     Additonal objects and advantages of the invention will be set forth in the description which follows, and part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to er plain the principles of the invention. 
         FIG.  1    is a schematic perspective view showing an example of a disk drive. 
         FIG.  2    is a schematic cross-sectional view showing a part of the disk drive. 
         FIG.  3    is a schematic plan view showing a suspension according to a first embodiment. 
         FIG.  4    is a schematic plan view showing a flexure shown in  FIG.  3   . 
         FIG.  5    is a schematic perspective cross-sectional view showing the flexure taken along line V-V in  FIG.  4   . 
         FIG.  6    is a schematic cross-sectional view showing the flexure shown in  FIG.  5   . 
         FIG.  7    is a view showing a comparative example of the flexure according to the first embodiment. 
         FIG.  8    is a schematic cross-sectional view showing a flexure according to a second embodiment. 
         FIG.  9    is a schematic cross-sectional view showing a flexure according to a third embodiment. 
         FIG.  10    is a schematic cross-sectional view showing a flexure according to a fourth embodiment. 
         FIG.  11    is a schematic cross-sectional view showing a flexure according to a fifth embodiment. 
         FIG.  12    is a schematic cross-sectional view showing a flexure according to a sixth embodiment. 
         FIG.  13    is a schematic cross-sectional view showing a flexure according to a seventh embodiment. 
         FIG.  14    is a schematic cross-sectional view showing a flexure according to an eighth embodment. 
         FIG.  15    is a schematic cross-sectional view showing a flexure according to a ninth embodiment. 
         FIG.  16    is a schematic cross-sectional view showing a flexure accord to a tenth embodiment. 
         FIG.  17    is a schematic partial plan view showing a flexure according to an eleventh embodiment. 
         FIG.  18    is a schematic cross-sectional view showing a flexure taken along line XVIII-XVIII of  FIG.  17   . 
         FIG.  19    is a schematic partial plan view showing a flexure according to a twelfth embodiment. 
         FIG.  20    is a schematic cross-sectional view showing a flexure taken along line XX-XX of  FIG.  19   . 
         FIG.  21    is a schematic cross-sectional view showing a flexure according to a thirteenth embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     First Embodiment 
       FIG.  1    is a schematic perspective view showing an example of a disk drive (HDD)  1 . In the example shown in  FIG.  1   , the disk drive  1  comprises a casing  2 , a plurality of magnetic disks (hereafter referred to simply as disks  4 ) rotating around a spindle  3 , a carriage  6  that can turn around a pivot  5 , and a positioning motor (voice coil motor)  7  for driving the carriage  6 . The casing  2  is sealed by a lid (not shown). 
       FIG.  2    is a schematic cross-sectional view showing a part of the disk drive  1 . As shown in  FIG.  1    and  FIG.  2   , a plurality of arms (carriage arms)  8  are provided on the carriage  6 . A suspension  10  is attached to each of distal end portions of the plurality of arms  8 . A slider  11 , which constitutes a magnetic head, is provided on each of the distal end portions of the suspensions  10 . 
     When the disks  4  rotate at a high speed, air flows in between the disks  4  and the sliders  11 , and air bearing is thereby formed. When the carriage  6  is turned by the positioning motor  7 , the suspension  10  moves in the radial direction of the disk  4 , and the slider  11  moves to a desired track of the disk  4 . 
     As shown in  FIG.  2   , the disks  4  include a first disk  4 A and a second disk  4 B. The first disk  4 A is opposed to the second disk  4 B with a predetermined interval. A first suspension  10 A and a second. suspension  10 B are included in the plurality of suspensions  10  provided on the risk drive  1 . 
     The first suspension  10 A and the second suspension  10 B are located between the first disk  4 A and the second disk  4 B. The first suspension  10 A is opposed to the second suspension  10 B in a thickness direction of the casing  2 . The plurality of disks  4  are not limited to two disks, but may be three or more disks. The quantity of suspensions  10  is arbitrarily changed according to the number of disks  4 . 
       FIG.  3    is a schematic plan view showing the suspension  10  according to the first embodiment.  FIG.  4    is a schematic plan view showing the flexure  30  shown in  FIG.  3   . The suspension  10  comprises a baseplate  21 , a load beam  22 , and a flexure  30 . 
     Both the load beam  22  and the flexure  30  extend in the longitudinal direction of the suspension  10 . In the following descriptions, the longitudinal direction of the suspension  10 , the load beam  22 , and the flexure  30  is defied as a longitudinal direction X, and a direction orthogonal to the longitudinal direction X is defined as a transverse direction Y of the suspension  10 , the load beam  22 , the flexure  30 , and the like. 
     A direction intersecting (for example, orthogonal to) the longitudinal direction. X and the transverse direction Y is defined as a thickness direction Y of the suspension  10 , the load beam  22 , the flexure  30 , and the like is defined as a thickness direction Z. Furthermore, a sway direction S is defined as indicated by an arc-shaped arrow near the distal end of the load beam  22 . 
     The base plate  21  is formed of, for example, a metallic material such. as stainless steel. The thickness of the baseplate  21  is, for example, 120 μm but is not limited to this example. A boss portion  23  for attaching the suspension  10  to the arm  8  (shown in  FIG.  1    and  FIG.  2   ) provided at the carriage  6  is provided at the baseplate  21 . 
     The load beam  22  is formed of a metallic material such as stainless steel. A thickness of the load beam  22  is, for example, in a range of 30 to 80 μm. The load beam  22  has a shape tapered toward a distal end (left side of the figure). 
     The load beam  22  has a spring portion  24  at one of ends in the longitudinal direction X. The load beam  22  is fixed to the baseplate  21  by, for example, spot welding using a laser, at a weld portion  25 . The load beam  22  is elastically supported by the base plate  21  via the spring portion  24 . 
     The flexure  30  is arranged along the baseplate  21  and the load beam  22 . The flexure  30  is fixed to the baseplate  21  and the load beam  22  by, for example, spot welding using a laser, at the weld portion  25 . 
     The flexure  30  includes a distal side portion  31  (left side in the figure) that overlaps with the load beam  22 , and a flexure tail  32  that extends from the baseplate  21  toward a rear side of the baseplate  21  (right side in the figure). 
     The flexure  30  comprises a metal base  40  formed of, for example, a thin stainless steel plate and a wiring portion  50  provided along the metal base  40 . The flexure  30  has a stacked layer structure. The metal base  40  is often referred to as a stainless steel layer. A thickness of the metal base  40  is smaller than a thickness of the load beam  22 . 
     At the distal side portion  31 , the flexure  30  further includes a tongue  33  and a pair of outriggers  34 A and  345 . A slider  11  is mounted on the tongue  33 . For example, an element capable of converting magnetic signals and electrical signals, such as an MR element, is provided at the distal end portion of the slider  11 . 
     At the distal side portion  31 , the wiring portion  50  is electrically connected to the element of the slider  11  via a terminal  51 . These elements are used for access soon as writing data to or reading data from the disks or the like. A head gimbal assembly is constituted by the slider  11 , the load beam  22 , the flexure  30 , and the like. 
     A pair of outriggers  341  and  345  are arranged on both sides of the tongue  33  in the transverse direction Y. The pair of outriggers  34 A and  34 B are shaped to protrude toward both outer sides of the tongue  33  in the transverse direction Y. The tongue  33  and the pair of outriggers  34 A and  34 B are parts of the metal base  40  and their outlines are formed by, for example, etching. 
     The gimbal portion  35  is composed of the tongue  33 , the pair of outriggers  347  and  343 , and the like. The gimbal portion  35  is formed at the distal side portion  31  of the flexure  30 . Micro actuator elements  36 A and  36 B are mounted on the gimbal portion  35 . The micro actuator elements  36 A and  36 B have a function of rotating the tongue  33  in the sway direction S. 
     The micro actuator elements  36 A and  36 B are arranged on both sides of the slider  11  in the transverse direction Y. The micro actuator elements  36 A and  36 B are formed of piezoelectric elements of lead zirconate titanate (PZT) or the like. The micro actuator elements  36 A and  36 B are fixed to actuator support portions of the tongue  33  by conductive adhesives or the like, respectively. 
       FIG.  5    is a schematic perspective cross-sectional view showing the flexure  30  taken along line V-V in  FIG.  4   .  FIG.  6    is a schematic cross-sectional view showing the flexure  30  shown in  FIG.  5   . In  FIG.  5    and  FIG.  6   , the cross section is viewed from the flexure tail  32  side. 
     The direction orthogonal to the extension direction of the wiring portion  50  may be hereinafter referred to as a “width direction of the wiring portion  50 ”. The width direction of the wiring portion  50  is varied according to the position of the wiring portion  50  in the longitudinal direction X. For example, in the example shown in  FIG.  5    and  FIG.  6   , the extension direction of the wiring portion  50  corresponds to the longitudinal direction X, and the width direction of the wiring portion  50  corresponds to the transverse direction Y. 
     As described above, the flexure  30  includes the metal base  40  and the wiring portion  50 . As shown in  FIG.  5    and  FIG.  6   , the metal base  40  includes a pair of first portions  41 A and  41 B. 
     The pair of first portions  41 A and  41 B are located on both sides of the flexure  30  in the transverse direction Y. A width in the transverse direction Y of the metal base  40  is larger than a width in the transverse direction Y of the wiring portion  50 . From another viewpoint, the metal base  40  can be visually recognized in planar view of watching the suspension  10  from the flexure  30  side. 
     In the example shown in  FIG.  5    and  FIG.  6   , the pair of first portions  41 A and  41 B are formed to have a rectangular cross section. The pair of first portions  41 A and  41 B may have a square cross section. The pair of first portions  41 A and  41 B may have a cross section including a curved surface. The sizes of the pair of first portions  41 A and  41 B are approximately equal. 
     The first portion  41 A has a surface  42 , a surface  43  opposite to the surface  42  in the thickness direction Z, and a side surface  44  that connects the surface  42  and the surface  43 . The first portion  41 B has a surface  45 , a surface  46  opposite to the surface  45  in the thickness direction  5 , and a side surface  47  that connects the surface  45  and the surface  46 . 
     At the distal side portion  31 , the surfaces  43  and  46  are, for example, surfaces opposed to the load beam  22  (shown in  FIG.  3   ). In the thickness direction Z, the surface  42  is located in the same plane as the surface  45 , and the surface  43  is located in the same plane as the surface  46 . 
     In the transverse direction Y, the side surfaces  44  and  47  are opposed to each other. In the example shown in  FIG.  5    and  FIG.  6   , the side surfaces  44  and  47  are, for example, surfaces substantially parallel to a plane defined by the longitudinal direction X and the thickness direction Z. 
     The wiring portion  50  includes a base insulating layer  61 , a conductor layer  71  overlapping with the base insulating layer  61 , and a cover insulating layer  81  overlapping with the conductor layer  71 . The stacking direction of the wiring portion  50  is a direction along the thickness direction Z. 
     The base insulating layer  61  and the cover insulating layer  81  are formed of, for example, an electrically insulating resin material such as polyimide. In the example shown in  FIG.  5    and  FIG.  6   , the base insulating layer  61  has a uniform thickness in the transverse direction Y. 
     The base insulating layer  61  has a surface  62  (first surface), and a surface  63  (second surface) opposite to the surface  62  in the thickness direction Z. The surface  62  is a surface with which the conductor layer  71  and cover insulating layer al are in contact. At the distal side portion  31 , the surfaces  63  is, for example, a surface opposed to the load beam  22  (shown in  FIG.  3   ). 
     In the example shown in  FIG.  5    and  FIG.  6   , the surface  63  in the thickness direction Z is located in the same plane as the surfaces  43  and  46 . The base insulating layer  61  further has an end surface  64  and an end surface  65  opposite to the end surface  64  in the transverse direction Y. The end surfaces  64  and  65  connect the surfaces  62  and  63 . 
     The cover insulating layer  81  has an end surface  82 , and an end surface  83  opposite to the end surface  82  in the transverse direction Y. In the thickness direction  3 , the end surface  64  is located directly under the end surface  82 , and the end surface  65  is located directly under the end surface  83 . 
     The conductor layer  71  is formed of a metallic material with high conductivity, such as copper. The conductor layer  71  is formed to have a predetermined pattern along the base insulating layer  61  by etching. Another method may be to form the conductor layer  71  by, for example, a layer formic g. process such as plating on the base insulating layer  61  masked with a predetermined pattern. 
     As shown in  FIG.  5    and  FIG.  6   , the conductor layer  71  includes a plurality of lines  72  arranged in the width direction of the wiring portion  50  (transverse direction Y in the example shown in  FIG.  5    and  FIG.  6   ). The plurality of lines  72  include, for example, read and write lines. The plurality of lines  72  are covered with the cover insulating layer  81 . 
     The cover insulating layer  81  is, located in a region between the pair of first portions  41 A and  41 B and the conductor layer  71 . The cover insulating layer  81  is located in regions between the plurality of  72 . Each of the plurality of lines  72  is thereby insulated . 
     The cover insulating layer  31  does not overlap with the conductive layer  71  in the thickness direction Z, in the region between the pair of first portions  41 A and  41 B and the conductive layer  71 , and the regions between the pair of lines  72 . The cover insulating layer  81  is in contact with the surface  62  of the base insulating layer  61  in these regions. 
     A plurality of grooves  84  are formed in the cover insulating layer  81 , in the region between the pair of first portions  41 A and  41 B and the conductor layer  71 , and the regions between the plurality of lines  72 . The plurality of grooves  84  are recessed toward the surface  62  and are formed along the conductor layer  71 . 
     In the example shown in  FIG.  5    and  FIG.  6   , the base insulating layer  61 , the conductor layer  71 , and the cover insulating layer  81  are located between the side surface  44  and the side surface  47  in the transverse direction Y. From another viewpoint, the wiring portion  50  is sandwiched between the side surface  44  and the side surface  47 . In the thickness direction  2 , the base insulating layer  61 , the conductor layer  71 , and the cover insulating layer  81  do not overlap with the bair of first portions  41 A and  41 B of the metal base  40 . 
     At least one of the base insulating layer  61  and the cover insulating layer  81  is in contact with the side surfaces  44  and  47  between the pair of first portions  41 A and  41 B. In the example shown in  FIG.  5    and  FIG.  6   , the base Insulating layer  61  and the cover insulating layer  81  are in contact with each of the side surfaces  44  and  47 . 
     More specifically, the end surface  64  and end surface  82  are in contact with the side surface  44 , and the end surface  65  and the end surface  83  are in contact with the side surface  47 . From the other viewpoint, no gap is formed between the end surfaces  64  and  82  and the side surface  44 , and no gap is formed between the end surfaces  65  and  83  and the side surface  47 . Portions that are not in contact with the base insulating layer  61  and the cover insulating layer  81  are formed on the side surfaces  44  and  47 . 
     As shown in  FIG.  6   , a thickness of the pair of first portions  41 A and  41 B is referred to as a thickness T 41 , a thickness of the wiring portion  50  is referred to as a thickness T 50 , a thickness of the base insulating layer  61  is referred to as a thickness T 61 , a thickness of the conductor layer  71  is referred to as a thickness T 71 , and a thickness of the cover insulating layer  81  is referred to as a thickness T 81 . 
     The thickness T 41  of the pair of first portions  41 A and  41 B is approximately equal to a distance between the surfaces  42  and  45  and the surfaces  43  and  46  in the thickness direction Z. The thickness T 50  of the wiring portion  50  is a thickness of a portion where the base insulating layer  61 , the conductive layer  71 , and the cover insulating layer  81  ail overlap in the thickness direction Z. 
     In the example shown in  FIG.  6   , the thickness  150  of the wiring portion  50  is a sum of the thickness T 61  of the base insulating layer  61 , the thickness T 71  of the conductor layer  71 , and the thickness T 81  of the cover insulating layer  81 . 
     The thickness T 61  of the base insulating layer  61  is approximately equal to a distance between the surface  62  and the surface  63  in the thickness direction Z. The thickness T 81  of the cover insulating layer  81  is, for example, a thickness in the region overlapping with the conductor layer  71 . The thickness T 81  of the cover insulating layer  81  is, for example, smaller than the thickness T 61  of the base insulating layer  61 . 
     The thickness T 50  of the wiring portion  50  is, for example, less than or equal to the thickness T 41  of the pair of first portions  41 A and  41 B (T 50 ≤T 41 ). In such. a case, the thickness of the flexure  30  at the portion shown in  FIG.  5    and  FIG.  6    becomes approximately equal to the thickness T 41  of the pair of first portions  41 A and  41 B. 
     In the example shown in  FIG.  6   , the thickness T 50  of the wiring portion  50  is approximately equal to the thickness T 41  of the pair of first portions  41 A and  41 B. The thickness  150  of the wiring portion  50  may be smaller than the thickness T 41  of the pair of first portions  41 A and  41 B. 
     The thickness T 41  of the first portions  41 A and  41 B is, for example, in a range from 11 to 50 μm. The thickness T 41  of the pair of first portions  41 A and  41 B is, for example, 18 μm. The thickness T 61  of the base insulating layer  61  is, for example, in a range from 5 to 20 μm. The thickness T 61  of the base insulating layer  61  is, for example, 6 μm. 
     The thickness T 81  of the cover insulating layer  81  is, for example, in a range from 2 to 10 μm. The thickness T 81  of the cover insulating layer  81  is, for example, 2 μm. The thickness T 71  of the conductor layer  71  is, for example, in a range from 4 to 16 μm. The thickness T 71  of the conductor layer  71  is, for example, 10 μm. 
     In at least a part of the flexure  30  shown in  FIG.  3    and  FIG.  4   , the metal base  40 , the base insulating layer  61 , the conductor layer  71 , and the cover insulating layer  81  do not all overlap at the same time. 
     In the flexure  30 , the example shown in  FIG.  5    and  FIG.  6    can be mainly applied to the range excluding, for example, a terminal of the wiring portion  50  provided on the flexure tail  32  side, the vicinity of the tongue  33 , the portion where a point-to-point construction part is formed, the portion where a via portion is formed, and the like. 
     The point-to-point construction part is a part where the wiring portion  50  is not in contact with the metal base  40 . For example, the point-to-point construction part is formed along the outriggers  34 A and  34 B. The via portion is, for example, a portion including a through hole which penetrates the base insulating layer  61 . 
     The configuration of the flexure  30  in the first embodiment can be applied not only to the portion indicated by line V-V, but also to, for example, a range between the portion where the pair of outriggers  34 A and  34 B are formed and the flexure tail  32 . The range includes the portions indicated by lines A-A, B-B, and C-C in  FIG.  4   , their vicinities, and the like. 
     As another example, the configuration of the flexure  30  can be applied to the flexure tail  32 . As yet another example, the configuration of the flexure  30  may be applied to a range where the flexure  30  overlaps with the load beam  22 . As yet another example, the configuration of the flexure  30  may be applied to a range where the flexure  30  does not overlap with the load beam  22 . 
     As yet another example, the configuration of the flexure  30  may be applied to each of the range where the flexure  30  overlaps with the load beam  22  and the range where the flexure  30  does not overlap with the load beam  22 . However, the range where the configuration of the flexure  30  can be applied changes depending on the shape of the suspension  10  and the like, and is not limited to the examples described above. 
     In the flexure  30  of the suspension  10  configured as described above, the conductor layer  71  does not overlap with the metal base  40  in the thickness direction least in part of the flexure  30 , and the metal base  40 , the base insulating layer  61 , the conductor layer  71 , and the cover insulation layer  81  do not all overlap at the same time. 
     The wiring portion  50  is provided or the metal base  40  such that at least one of the base insulating layer  61  and the cover insulating layer  81  is brought into contact with the side surfaces  44  and  47  between the pair of first portions  41 A and  41 B. Increase in the thickness of the flexure  30  can be suppressed and the flexure  30  can be made thinner by thus configuring the flexure  30 . 
       FIG.  7    shows a comparative example of the flexure  30  according to the first embodiment. In a flexure  300  shown in  FIG.  7   , the wiring portion  50  is provided on the metal base  40 . The base insulating layer  61  is provided on the metal base  40 , and the conductor layer  71  and the cover insulating layer  81  overlap with the base insulating layer  61 . 
     In this case, a thickness of the flexure  300  is a sum of a thickness of the metal base  40  and a thickness of the wiring portion  50 . The thickness of the flexure can be made smaller than the flexure  300  shown in  FIG.  7   , by configuring the flexure  30  as shown in  FIG.  5    and  FIG.  6   . 
     The base insulating layer  61 , the conductor layer  71 , and the cover insulating layer  81  are located between the side surface  44  and the side surface  47  in the transverse direction Y. Furthermore, since the thickness of the flexure  30  does not become larger than the thickness T 41  of the pair of first portions  41 A and  41 B by making the thickness T 50  of the wiring portion  50  smaller than or equal to the thickness T 41  of the pair of first portions  41 A and  41 B, increase in the thickness of the flexure  30  can be suppressed. 
     For example, when the thickness T 50  of the wiring portion  50  is substantially equal to the thickness T 41  of the pair of first portions  41 A and  41 B, the thickness of the flexure  30  can be made substantially equal to the thickness T 41  of the pair of first. portions  41 A and  41 B. 
     Furthermore, at least one of the base insulating layer  61  and the cover insulating is in contact with the side surfaces  44  and  47 . At least one of the base insulating layer  61  and the cover insulating. layer  81  supports the pair of first portions  41 A and  41 B in the transverse direction Y. The rigidity of the flexure  30  in the transverse direction Y can be thereby increased. The rigidity of the flexure  30  in the transverse direction Y may be referred to as “in-plane rigidity”. 
     In the example shown in  FIG.  5    and  FIG.  6   , the base insulating layer  61  and the cover insulating layer  81  are in contact with each of the side surfaces  44  and  47 . For this reason, the rigidity of the flexure  30  in the transverse direction Y can be made larger than that in a case where either of the base insulating layer  61  or the cover insulating layer  81  is in contact with the side surfaces  44  and  47 . 
     Furthermore, the in-plane rigidity can be maintained and the spring constant of the flexure  30  can be lowered in the flexure  30  of the first embodiment. A degree of freedom in designing of the vibration characteristics of the flexure  30  and the like can be thereby increased. 
     In accordance with the reduction of members stacked in the thickness direction Z and the reduction in thickness of the flexure  30 , for example, the degree of freedom in designing of the thickness T 61  of the base insulating layer  61  and the like can be increased in the wiring portion  50 . For example, the transmission characteristics in the flexure  30 , such as impedance matching, can easily be optimized by changing the thickness T 61  of the base insulating layer  61 . 
     Furthermore, the suspension  10  comprising the flexure  30  can be made thinner by making the flexure  30  thinner. Since such a suspension  10  can be applied to the disk drive  1  in which the distance between the disks  4  is made small, the disk drive  1  that can correspond to an increase in the number of disks  4  can be provided. 
     According to the embodiment, the flexure  30  of the suspension  10  that can be made thinner, and the suspension  10  can be provided. In addition to the above-described actions, various suitable actions can be obtained from the embodiment. 
     Next, the other embodiments will be described. In the other embodiments and modified examples described below, the same constituent elements as those in the first embodiment described above are denoted by the same reference numerals and their detailed descriptions may be omitted or simplified. 
     Second Embodiment 
       FIG.  8    is a schematic cross-sectional view showing a flexure  30  according to a second embodiment. The flexure  30  of the second embodiment is different from the first embodiment in a wiring portion  50 . 
     As shown in  FIG.  8   , the wiring portion  50  includes a base insulating layer  61 , a conductor layer  71 , and a cover insulating layer  81 . The cover insulating layer  81  has a surface  85  opposed to a surface  62 , and a surface  86  opposite to the surface  85  in the transverse direction Y. In the thickness direction Z, the surface  86  is located in the same plane as surfaces  42  and  45  of a pair of first portions  41 A and  41 B. A plurality of grooves  84  are formed in the cover insulating layer  81 . 
     Entire bodies of side surfaces  44  and  47  are in contact with the base insulating layer  61  and the cover insulating layer  81 . Portions that are not in contact with the base insulating layer  61  and the cover insulating layer  81  are not formed on the side surfaces  44  and  47 , and an interval between. the side surfaces  44  and  47  is filled with the base insulating layer  61  and the cover insulating layer  81 . Each of an end surface  64  and an end surface  82  is in contact with the side surface  44 , and each of an end surface  65  and an end surface  83  is in contact with the side surface  47 . 
     A thickness T 82  of the cover insulating layer  81  in a region between the pair of first portions  41 A and  41 B and a conductor layer  71  and a region between a plurality of lines  72  is larger than a thickness T 81  of the cover insulating layer  81  in a region overlapping with the conductive layer  71 . 
     In the region between the pair of first portions  41 A and  41 B and the conductor layer  71  and the region between the plurality of lines  72 , a sum of a thickness T 61  of the base insulating layer  61  and the thickness T 82  of the cover insulating layer  81  is substantially equal to a thickness  141  of the pair of first portions  41 A and  41 B. 
     In the configuration of the flexure  30  of the second embodiment, too, the same effects as those of the first embodiment can be obtained In the flexure  30  of the second embodiment, the interval between the side surface  44  and the side surface  47  is filled with the base insulating layer  61  and the cover insulating layer  81 . 
     The base insulating layer  61  and the cover insulating layer  81  are in contact with entire bodies of the side surfaces  44  and  47 . For this reason, the rigidity of the flexure  30  in the transverse direction Y can be further increased as compared to the first embodiment. 
     Third Embodiment 
       FIG.  9    is a schematic cross-sectional view showing a flexure  30  according to a third embodiment. The flexure  30  of the third embodiment is different from each of the above-described embodiments in a wiring portion  50 . 
     As shown in  FIG.  9   , a plurality of grooves  66  recessed from a surface  62  to a surface  63  are formed in a base insulating layer  61 . A plurality of lines  72  overlap with the plurality of grooves  66 , respectively. From another viewpoints, the plurality of lines  72  are formed along the plurality of grooves  66 . 
     At least a part ef a conductor layer  71  is buried in the base insulating layer  61 . In the example shown in  FIG.  9   , a depth D 66  of the grooves  66  is smaller than a thickness T 71  of the conductor layer  71 . For this reason, each of the plurality of lines  72  includes a portion  73  protruding above the groove  66  and a portion  74  buried in the groove  66 , in the thickness direction Z. In the example shown in  FIG.  9   , the thickness of the protruding portion  73  is greater than the thickness of the buried portion  74 . 
     In the configuration of the flexure  30  of the third embodiment, too, the same effects as those in each of the above-described embodiments can be obtained. In the flexure  30  of the third embodiment, since the plurality of lines  72  are buried in the plurality of grooves  66  in the base insulating layer  61 , respectively, the plurality of lines  72  can hardly be moved in the transverse direction Y. 
     In the manufacturing process, positioning the conductor layer  71  can easily be performed. The thickness of the protruding portion  73  may be smaller than the thickness of the buried portion  74  or the thickness of the protruding portion  73  may be equal to the thickness of the buried portion  74 . 
     Fourth Embodiment 
       FIG.  10    is a schematic cross-sectional view showing a flexure  30  according to a fourth embodiment. In the fourth embodiment, a depth D 66  of grooves  66  is larger than that in the third embodiment. 
     In the example shown in  FIG.  10   , the depth D 66  of the grooves  66  is substantially equal to a thickness T 71  of a conductor layer  71 . A plurality of lines  72  are buried in the plurality of grooves  66 , respectively. The plurality of lines  72  do not include portions  73  protruding above the grooves  66  as compared with the example shown in  FIG.  9   . A cover insulating layer  81  has a uniform thickness in the transverse direction Y. 
     In the configuration of the flexure  30  of the fourth embodiment, too, the same effects as those in each of the above-described embodiments can be obtained. In the flexure  30  of the fourth embodiment, since the plurality of lines  72  are buried in the plurality of grooves  66  of the base insulating layer  61 , respectively, the plurality of lines  72  can hardly be moved in the transverse direction Y. The depth P 66  of the grooves  66  is larger than the thickness  171  of the conductor layer  71 . In this case, the cover insulation layer  81  is partially buried in the grooves  66 . 
     Fifth Embodiment 
       FIG.  11    is a schematic cross-sectional view showing a flexure  30  according to a fifth embodiment. The flexure  30  of the fifth embodiment is different from each of the above-described embodiments in a wiring portion  50 . 
     As shown in  FIG.  11   , a base insulating layer  61  is located between a side surface  44  and a side surface  47 , while a conductor layer  71  and a cover insulating layer  81  are not located between the side surface  44  and the side surface  47 , in the transverse direction Y. 
     A thickness T 61  of a base insulating layer  61  is substantially equal to a thickness T 41  of a pair of first portions  41 A and  41 B. In the thickness direction Z, a surface  62  of the base insulating layer  61  is located in the same plane as surfaces  42  and  45  of the pair of first portions  41 A and  41 B, and a surface  63  of the base insulating layer  61  is located in the same plane as surfaces  43  and  46  of the pair of first portions  41 A and  41 B. 
     An end surface  64  is in contact with the side surface  44 , and an end face  65  is in contact with the side surface  47 . Portions which are not in contact with the base insulating layer  61  are not formed on the side surfaces  44  and  47 . End surfaces  82  and  83  are not in contact with the side surfaces  44  and  47 . 
     The conductor layer  71  and the cover insulating layer  81  overlap with the surface  62 . In the example shown in  FIG.  11   , the cover insulating layer  81  partially overlaps with surfaces  42  and  45  of the pair of first portions  41 A and  41 B. 
     A width of the cover insulating layer  81  is larger than a width of the base insulating layer  61  in the transverse direction Y. From another viewpoint, the end surfaces  82  and  83  are farther from the conductor layer  71  than the side surfaces  44  and  47  (end surfaces  64  and  65 ) in the transverse direction. 
     In the configuration of Id flexure  30  of the fifth embodiment, too, the same effects as those in each of the above-described embodiments can be obtained. In the flexure  30  of the fifth embodiment, the base insulating layer  61  is located between the side surface  44  and the side surface  47 . For this reason, the thickness of the flexure  30  can be reduced by the amount corresponding to the thickness T 61  of the base insulating layer  61 . 
     Furthermore, a process of reducing the thickness T 61  of the base insulating layer  61  can be reduced in the manufacturing process, by making the thickness of the base insulating layer  61  the same as the thickness T 41  of the pair of first portions  41 A and  41 B. The width of the cover insulating layer  81  may be smaller than the width of the base insulating layer  61 , and the width of the cover insulating layer  81  may be equal to the width of the base insulating layer  61 , in the short direction Y. 
     Sixth Embodiment 
       FIG.  12    is a schematic cross-sectional view showing a flexure  30  according to a sixth embodiment. The flexure  30  of the sixth embodiment is different from each of the above-described embodiments in a wiring portion  50 . 
     The flexure  30  further comprises an air layer  91  that is in contact with a surface  63  of a base insulation layer  61 . A surface  63  of the base insulating layer  61  is in contact with the air layer  91  between a side surface  44  and a side surface  47 . A conductor layer  71  overlaps with the air layer  91 . 
     As shown in  FIG.  12   , the surface  63  of the base insulating layer  61  is separated from surfaces  43  and  46  of the pair of first portions  41 A and  41 B in the thickness direction Z. From another viewpoint, the surface  63  of the base insulating layer  61  is not located in the same plane as surfaces  42  and  45  and the surfaces  43  and  46  of the pair of first portions  41 A and  41 B. 
     A thickness T 61  of the base insulating layer  61  is smaller than a thickness T 61  of the base insulating layer  61  shown in  FIG.  6   . For example, the base insulating layer.  61  shown in  FIG.  12    is formed by over-etching a backup layer to be described later, when removed in an etching process. 
     When the flexure  30  overlaps with the load beam  22 , the air layer  91  is located just above the load beam  22 . A thickness T 91  of the air layer  91  can be arbitrarily changed by changing the thickness T 61  of the base insulating layer  61 . 
     In the configuration of the flexure  30  of the sixth embodiment, too, the same effects as those in each of the above-described embodiments can be obtained. In the flexure  30  of the sixth embodiment, the air layer  91  of the flexure  30  overlaps to be opposed to the load beam  22  when a suspension  10  is formed. 
     For this reason, the range of adjustment of the dielectric constant in the flexure  30  is widened by providing the air layer  91 , and the degree of freedom in designing the flexure  30  can be widened for optimizing the transmission characteristics. 
     The air layer  91  is formed entirely between the side surfaces  44  and  47  in the transverse direction Y, but the air layer  91  may be partially formed between the side surfaces  44  and  47  in the transverse direction Y. The air layer  91  is formed with a uniform thickness in the transverse direction Y, but the thickness of the air layer  91  may be changed arbitrarily in the transverse direction. 
     Seventh Embodiment 
       FIG.  13    as a schematic cross-sectional view showing a flexure  30  according to a seventh embodiment. The flexure  30  of the seventh embodiment is different from each of the above-described embodiments in comprising a support layer  92 . 
     As shown in  FIG.  13   , the flexure  30  further comprises a support layer  92  which supports a wiring 
     The support layer  92  is, for example, a backup layer used in a manufacturing process of the flexure  30 . 
     A pair of first portions  41 A and  41 B and the wiring portion  50  overlap with the support layer  92 . More specifically, the support layer  92  is in contact with surfaces  43  and  46  of the pair of first portions  41 A and  41 B and a surface  63  of a base insulating layer  61 . 
     The support layer  92  is formed of, for example, an electrically insulating resin material such as polyimide. In the example shown in  FIG.  13   , the support layer  92  has a uniform thickness in the transverse direction Y. For example, the thickness of the support layer  92  is smaller than a thickness of the base insulating layer  61 . 
     In the configuration of the flexure  30  of the seventh embodiment, too, the same effects as those in each of the above-described embodiments can be obtained. In the flexure  30  of the seventh embodiment, the case insulating layer  61 , a conductor layer  71 , and a cover insulating layer  81  are located between a side surface  44  and a side surface  47  in the transverse direction Y. For this reason, even when the flexure  30  comprises the support layer  92 , increase in thickness of the flexure  30  can be suppressed. 
     Increase in the thickness of the flexure  30  can be suppressed by reducing the thickness of the support layer  32 . Furthermore, by providing the support layer  92  formed of an electrically insulating resin material, insulation from the load beam  22  can easily be executed when forming the suspension  10 . In this case, for example, the flexure  30  is fixed to the load beam  22  by means of an adhesive. 
     Furthermore, in the manufacturing process, the number of processes can be reduced since a process for removing the support layer  92  is unnecessary. In the example shown in  FIG.  13   , the support layer  92  overlaps with the wiring portion  50  and the pair of first portions  41 A and  41 B, but the support layer  92  may overlap with only the wiring portion  50 . 
     Eighth Embodiment 
       FIG.  14    is a schematic cross-sectional view showing a flexure  30  according to an eighth embodiment. The eighth embodiment is different from the seventh embodiment in a support layer  92  provided at the flexure  30 . In the example shown in  FIG.  14   , the support layer  92  is formed. of, for example, a metallic material such as copper. The support layer  92  is formed by, for example, a method such as plating or sputtering. 
     In the configuration of the flexure  30  of the eighth embodiment, too, the same effects as those of the above-described embodiments can be obtained. In the flexure  30  of the eighth. embodiment, the support layer  92  can be made to act as a ground layer of a conductor layer  71  by forming the support layer  92  of a metallic material. The electrical characteristics in the flexure  30  can be improved by providing a highly conductive ground layer near the conductor layer  71 . 
     In the example shown in  FIG.  14   , the support layer  92  overlaps with each of the wiring portion  50  and the pair of first portions  41 A and  41 B, but the support layer  92  may overlap with only the wiring portion  50 . 
     Ninth Embodiment 
       FIG.  15    is a schematic cross-sectional view showing a flexure  30  according to a ninth embodiment. The flexure  30  of the ninth embodiment is different from each of the above-described embodiments in comprising a connection portion  93 . 
     As shown in  FIG.  15   , the flexure  30  further comprises the connection portion  93 . The connection portion  93  is formed of, for example, a metallic material such as copper. The connection portion  93  is formed by, for example, a method such as plating or sputtering. In the transverse direction Y, for example, the connection portion  93  is located between a side surface  44  and a side surface  47 . The connection portion  93  does not overlap with, for example, a pair of first portions  41 A and  41 B. 
     The connection portion  93  is electrically connected to at least one of the plurality of lines  72 . The connection portion  93  includes a connect portion  94  and a connection portion  95 . The plurality of lines  72  include lines  72 A to  72 D. 
     The connection portion  94  electrically connects the first portion  41 B with the line  72 A. The connection portion  94  is connected to, for example, the side surface  47  of the first portion  415 . The connection portion  95  electrically connects the line  72 B with the line  72 D. 
     The line  72 C that is not connected to the connection portion  95  is located between. the line  72 B and the line  72 D. Since a base insulating layer  61  is located between the connection portion  94  and the connection portion  95 , the connection portion  94  is insulated from the connection portion  95 . 
     In the example shown in  FIG.  15   , the lines  72 A,  72 B, and  72 D are buried in the base insulating layer  61 , but the line  72 C is not buried in the base insulating. layer  61 . A thickness of the lines  72 A,  72 B, and  72 D is larger than, for example, a thickness of the line  72 C. By thus providing the line  72 C, the line  72 C can be insulated from the connection portion  95 , and the line  72 B and the line  72 D can be electrically connected to each other by the connection portion  95 . 
     In the configuration of the flexure  30  of the ninth embodiment, too, the same effects as those in each of the above-described embodiments can be obtained. In the flexure  30  of the ninth embodiment, increase in the thickness of the flexure  30  can be suppressed since the connection portion  93  is located between the side surface  44  and the side surface  47  in the transverse direction Y. 
     The connection portion  93  can be used to ground the conductor layer  71  to the metal base  40  or can be used as a jumper to connect the plurality of lines  72 . The electrical characteristics in the flexure  30  can be thereby improved. 
     The shape of the connection portion  93  is not limited to the above-described example. Either the connection portion  94  used to ground the conductor layer  71  or the connection  95  used as a jumper to connect the plurality of lines  72  to each other may be provided at the connection portion  93 . The connection between the plurality of lines can be modified arbitrarily. 
     Tenth Embodiment 
       FIG.  16    is a schematic cross-sectional view showing a flexure  30  according to a tenth embodiment. The flexure  30  of the tenth embodiment is different from each of the above-described embodiments in a wiring portion  50 . 
     As shown in  FIG.  16   , a pair of first portions  41 A and  41 B overlap with a base insulating layer  61 . More specifically, the pair of first portions  41 A and  41 B are in contact with a surface  62  of the base insulating layer  61 . From. another viewpoint, the base insulating layer  61  is not located between a side surface  44  and a side surface  47  in the transverse direction Y. 
     A conductor layer  71  and a cover insulating layer  81  are located between the side surface  44  and the side surface  47  in the transverse direction Y. End surfaces  82  and  83  of a cover insulating layer  81  are in contact with the side surfaces  44  and  47 , respectively. Portions that are not in contact with the cover insulating layer  81  are formed on the side surfaces  44  and  47 . 
     In the configuration of the flexure  30  of the tenth embodiment, too, the same effects as those in each of the above-described embodiments can be obtained. In the flexure  30  of the tenth embodiment, the base insulating layer  61  is not located between the side surface  44  and the side surface  47 . 
     For this reason, in the example shown in  FIG.  16   , the conductor layer  71  and the cover insulating layer  81  can be more separated from surfaces  42  and  45  of the pair of first portions  41 A and  41 B in the thickness direction Z than in the example shown in  FIG.  6   . 
     In the flexure  30  of the tenth embodiment, the conductor layer  71  can be separated not only from the metal base  40  but also from a load beam  22  by making the surfaces  42  and  45  of the pair of first portions  41 A and  41 B overlap with the load beam  22  so as to be opposed to the load beam  22  when a suspension  10  is formed. 
     Differences in electrical characteristics from a point-to-point construction portion and the like, which occur in the flexure  30 , can be thereby made small. The support layer  92  described with reference to  FIG.  13    may be applied to the base insulating layer  61  of the flexure  30  of the tenth embodiment. 
     Eleventh Embodiment 
       FIG.  17    is a schematic partial plan view showing a flexure  30  according to an eleventh embodiment.  FIG.  18    is a schematic cross-sectional view showing the flexure  30  taken along line XVIII-XVIII of  FIG.  17   .  FIG.  17    shows the flexure  30  viewed from a cover insulating layer  81  side. The flexure  30  of the eleventh embodiment is different from each of the above-described embodiments in a metal base  40 . 
     As shown in  FIG.  17    and  FIG.  18   , the metal base  40  further includes a second portion  48  connected to a pair of first portions  41 A and  41 B. The second portion  48  functions as a “furring” that connects the pair of first portions  41 A and  41 B. 
     In  FIG.  17   , an area where the second portion  48  is formed is marked with dots. As shown in  FIG.  17   , the second portion  48  is formed on a part of the metal base  40  along the longitudinal direction X. A range in which the second portion  48  is formed can be changed arbitrarily. 
     As shown in  FIG.  18   , the second portion  48  is connected to each of side surfaces  44  and  47  in the short direction Y. For example, the second portion  48  is formed integrally with the pair of first portions  41 A and  41 B. 
     The second portion  48  is formed by, for example, half-etching a portion of the metal base  40 , which corresponds to the second portion  48 , in an etching process when, for example, forming the metal base  40 . The second portion  48  has a uniform thickness in the transverse direction Y. 
     A thickness T 48  of the second portion  48  is smaller than a thickness T 41  of the pair of first portions  41 A and  41 B. A thickness T 48  of the second portion  48  is, for example, smaller than or equal to a half of a thickness T 41  of the pair of first portions  41 A and  41 B. As yet another example, the thickness T 48  of the second portion  48  is smaller than or equal to a quarter of the thickness T 41  of the pair of first portions  41 A and  41 B. 
     The second portion  48  overlaps with a base insulating layer  61 , a conductor layer  71 , and a cover insulating layer  81 , in the thickness direction  2 . The base insulating layer  61  and the cover insulating layer  81  are in contact with each of the side surfaces  44  and  47 . 
     In the example shown in  FIG.  18   , the base insulating layer  61 , the conductor layer  71 , and the cover insulating layer  81  are located between the side surface  44  and the side surface  47  in the transverse direction Y. A sum of the thickness T 48  of the second portion  48  and a thickness T 50  of a wiring portion  50  is, for example, smaller than or equal to the thickness T 41  of the pair of first portions  41 A and  41 B. 
     In the example shown in  FIG.  18   , a sum of the thickness T 48  of the second portion  48  and the thickness T 50  of the wiring portion  50  is smaller than the thickness T 41  of the pair of first portions  41 A and  41 B. For this reason, the wiring portion  50  does not project more than the surfaces  42  and  45  in the thickness direction Z. 
     In the configuration of the flexure  30  of the eleventh embodiment, too, the same effects as those in each of the above-described embodiments can be obtained. In the flexure  30  of the eleventh embodiment, increase in the thickness of the flexure  30  can be suppressed since the wiring portion  50  is located between the side surface  44  and the side surface  47 . Furthermore, the rigidity of the flexure  30  in the transverse direction Y can be further increased by forming the second portion  48  connected to the pair of first portions  41 A and  41 B. 
     Twelfth Embodiment 
       FIG.  19    is a schematic partial plan view showing a flexure  30  according to a twelfth embodiment.  FIG.  20    is a schematic cross-sectional view showing the flexure  30  taken along line XX-XX of  FIG.  19   . The flexure  30  of the twelfth embodiment is different from the eleventh embodiment in that a second portion  48  includes an opening  49 . 
     As shown in  FIG.  19    and  FIG.  20   , the second portion  48  of a metal base  40  includes the opening 49 . The opening  49  overlaps with a conductor layer  71  in the thickness direction Z. In a plurality of lines  72 A to  72 D, the lines  72 A and  72 B overlap with the opening  49 , and the lines  72 C and  72 D do net overlap with the opening  49 . 
     In the example shown in  FIG.  19   , three openings  49  are formed along the longitudinal direction X. The number of openings  49  may be two or less, or four or more. Two or more openings  49  may be formed in the width direction of the wiring portion  50  (transverse direction Y in the example shown in  FIG.  19    and  FIG.  20   ). The size of the openings  49  may be changed arbitrarily. The number and range of lines overlapping with the opening  49  can be changed arbitrarily by changing the size of openings  49 . 
     In the configuration of the flexure  30  of the twelfth embodiment, the same effects as those in each of the above-described embodiments can be obtained. In the flexure  30  of the twelfth embodiment, adjustment of the electrical characteristics of the flexure  30  and the like can be executed by forming the openings  49  in the second portion  48 . 
     Thirteenth Embodiment 
       FIG.  21    is a schematic cross-sectional view showing a flexure  30  according to a thirteenth embodiment. The flexure  30  of the thirteenth embodiment is different from each of the above-described embodiments in comprising a plurality of conductor layers. 
     As shown in  FIG.  21   , a wiring portion  50  includes a base insulating layer  61 , a plurality of conductor layers, and a cover insulating layer  81 . The plurality of conductor layers include a first conductor layer  75  and a second conductor layer  76  that overlaps with the first conductor layer  75 . The first conductor layer  75  and the second conductor layer  76  include a plurality of lines  77  and  78 , respectively. 
     The first conductor layer  75  is in contact with a surface  62  of the base insulating layer  61 . The first conductor layer  75  is located between the side surface  44  and the side surface  47  in the transverse direction Y. The plurality of lines  78  are provided to overlap with the plurality of lines  77 , respectively. 
     A portion  87  of the cover insulation layer  81  is provided between the first conductor layer  75  and the second conductor layer  76 . The first conductor layer  75  and the second conductor layer  76  are insulated by a cover insulating layer  81 . A surrounding of the second conductor layer  76  is covered with the cover insulating layer  81 . 
     In the configuration of the flexure  30  of the thirteenth. embodiment, too, the same effects as those in the above-mentioned embodiments can be obtained. In the flexure  30  of the thirteenth embodiment, since the first conductor layer  75  is provided between the side surface  44  and the side surface  47  even in a case where a plurality of conductor layers are provided, increase in a thickness T 30  of the flexure  30  can be suppressed and the flexure  30  can be made thinner. 
     The thickness of the first conductor layer  75  may be equal to or different from. the thickness of the second conductor layer  76 . The number of conductor layers is not limited to two, but may be three or more. Providing a plurality of conductor layers, similarly to the flexure  30  of the thirteenth embodiment can be applied to each of the above-described embodiments. 
     In implementing. the inventions disclosed in the above embodiments, not only the specific configurations of the shape of the load beam and the flexure, but also the specific configurations of each element that constitutes the disk drive suspension can be changed variously. 
     The plurality of lines  72  may have different thicknesses. The grooves  66  described with reference to the third and fourth embodiments can also be arbitrarily applied to the base insulating layer  61  described in the fifth and subsequent embodiments. The air layer  91  described with reference to the sixth embodiment can also be arbitrarily applied to the other embodiments. 
     Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.