Wired circuit board

Abstract

To provide a wiring circuit board capable of suppressing a difference between the thickness of a first pedestal and the thickness of a second pedestal.SOLUTION: The suspension board with circuit 1 includes a first insulating layer 12, a wire pattern 133, a second insulating layer 14, and pedestals 15A, 15B. The line pattern 133 includes first lines 133A to 133D overlapping the pedestal 15A, and second lines 133E to 133H overlapping the pedestal 15B. The widths 133E of the second wiring lines W2 to 133H are the same as the widths 133A of the first wiring lines W1 to 133D, the interval 133E between the second wiring lines 133H to is the same as the interval D2 between the first wiring lines to, and the number of the second wiring lines to is the same as the number of the first wiring lines to. 133A 133A 133D 133H 133D 133E D1.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a printed circuit board. [Background technology]

[0002] Conventionally, a suspension board with a circuit on which a slider having a magnetic head can be mounted has been known as a wired circuit board. The suspension board with a circuit includes a base that supports the slider. The base includes an insulating base layer, a conductor layer disposed on the insulating base layer, and an insulating cover layer that covers the conductor layer (see, for example, Patent Document 1 below). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-81544 Summary of the Invention [Problem to be solved by the invention]

[0004] In a suspension board with circuit such as that described in Patent Document 1, when multiple wirings are arranged at the location where the pedestal is to be provided, the number, wiring width, and spacing of the wirings overlapping the first pedestal may differ from the number, wiring width, and spacing of the wirings overlapping the second pedestal, which may result in a difference in height between the first pedestal and the second pedestal.

[0005] The present invention provides a wired circuit board that can prevent the thickness of the first base from differing from the thickness of the second base. [Means for solving the problem]

[0006] The present invention [1] is a wiring circuit board on which electronic components can be mounted, comprising: a first insulating layer; a wiring pattern disposed on the first insulating layer in a thickness direction of the first insulating layer, the wiring pattern overlapping the electronic component in the thickness direction when the electronic component is mounted on the wiring circuit board; a second insulating layer disposed on the first insulating layer in the thickness direction and covering the wiring pattern; a first base disposed on the second insulating layer in the thickness direction and supporting the electronic component when the electronic component is mounted on the wiring circuit board; and a second base disposed at a distance from the first base in the thickness direction and supporting the electronic component when the electronic component is mounted on the wired circuit board, the wiring pattern having a plurality of first wirings overlapping the first base in the thickness direction and a plurality of second wirings overlapping the second base in the thickness direction, the width of each of the plurality of second wirings being the same as the width of each of the plurality of first wirings, the spacing between the plurality of second wirings being the same as the spacing between the plurality of first wirings, and the number of the plurality of second wirings being the same as the number of the plurality of first wirings.

[0007] According to this configuration, the width, spacing and number of the plurality of second wirings overlapping the second seat are the same as the width, spacing and number of the plurality of first wirings overlapping the first seat.

[0008] Therefore, it is possible to prevent the thickness of the first base from being different from the thickness of the second base.

[0009] The present invention [2] includes the wired circuit board of [1] above, wherein the wired circuit board further includes a plurality of terminals that are electrically connected to the electronic component when the electronic component is mounted on the wired circuit board, the plurality of first wirings includes a first connection wiring that is connected to one of the plurality of terminals, and the plurality of second wirings includes a second connection wiring that is connected to one of the plurality of terminals.

[0010] The present invention [3] includes the wired circuit board according to the above [2], in which the number of the second connection wires is smaller than the number of the first connection wires.

[0011] According to this configuration, even if the number of second connection wirings is smaller than the number of first connection wirings, i.e., even if the number of first connection wirings overlapping the first pedestal is different from the number of second connection wirings overlapping the second pedestal, the width, spacing and number of the multiple second wirings including the second connection wirings are the same as the width, spacing and number of the multiple first wirings including the first connection wirings.

[0012] Therefore, it is possible to prevent the thickness of the first base from being different from the thickness of the second base.

[0013] The present invention [4] includes the wired circuit board of the above [2] or [3], wherein the plurality of second wirings includes dummy wirings that are not connected to any of the plurality of terminals.

[0014] With this configuration, even if the number of second connection wirings is smaller than the number of first connection wirings, by adding dummy wirings, the width, spacing and number of the multiple second wirings can be matched with the width, spacing and number of the multiple first wirings.

[0015] Therefore, by using the dummy wiring, it is possible to prevent the thickness of the first pedestal from being different from the thickness of the second pedestal.

[0016] The present invention [5] includes the wired circuit board of [4] above, wherein the wired circuit board further comprises a metal support layer, the first insulating layer is disposed between the metal support layer and the wiring pattern in the thickness direction, has a through hole, and the dummy wiring is connected to the metal support layer through the through hole of the first insulating layer.

[0017] The present invention [6] includes the wired circuit board according to the above [2] or [3], wherein the plurality of second wirings include branch wirings branched from the second connection wirings.

[0018] With this configuration, even if the number of second connection wirings is smaller than the number of first connection wirings, by adding branch wirings, the width, spacing and number of the multiple second wirings can be matched with the width, spacing and number of the multiple first wirings.

[0019] Therefore, it is possible to prevent the thickness of the first base from being different from the thickness of the second base.

[0020] The present invention [7] includes the wired circuit board of [2] or [3] above, in which the plurality of second wirings include one of the second connection wirings, another second connection wiring independent from the one second connection wiring, a first branch wiring branched from the one second connection wiring, and a second branch wiring branched from the other second connection wiring.

[0021] According to this configuration, even if the number of second connection wirings is smaller than the number of first connection wirings, by adding the first branch wirings and the second branch wirings, the width, spacing and number of the multiple second wirings can be matched with the width, spacing and number of the multiple first wirings.

[0022] Therefore, it is possible to prevent the thickness of the first base from being different from the thickness of the second base.

[0023] The present invention [8] includes the wired circuit board of the above [7], in which the first branch wiring is arranged between the one second connection wiring and the other second connection wiring, and the second branch wiring is arranged on the opposite side of the first branch wiring with respect to the other second connection wiring.

[0024] The present invention [9] includes the wired circuit board of the above [7], in which the first branch wiring is arranged between the one second connection wiring and the other second connection wiring, and the second branch wiring is arranged between the first branch wiring and the one second connection wiring.

[0025] The present invention

[10] includes the wired circuit board of [2] or [3] above, wherein the wiring pattern further has a third wiring that does not overlap with either the first base or the second base in the thickness direction, and the plurality of second wirings include branch wirings branching from the third wiring.

[0026] With this configuration, even if the number of second connection wirings is smaller than the number of first connection wirings, by adding branch wirings from the third wirings that do not overlap with either the first or second pedestal, the width, spacing and number of the multiple second wirings can be matched with the width, spacing and number of the multiple first wirings.

[0027] Therefore, it is possible to prevent the thickness of the first base from being different from the thickness of the second base.

[0028] The present invention

[11] comprises the wired circuit board of any one of the above [1] to

[10] , wherein the electronic component is a slider having a magnetic head.

[0029] With this configuration, it is possible to prevent the slider from being mounted at an angle relative to the printed circuit board. [Effects of the Invention]

[0030] According to the wired circuit board of the present invention, it is possible to prevent the thickness of the first base from being different from the thickness of the second base. [Brief explanation of the drawings]

[0031] [Figure 1] Fig. 1 is a plan view of a suspension board with circuit as one embodiment of the wired circuit board of the present invention, in which the first insulating layer and the second insulating layer are omitted. [Figure 2] 2 is a cross-sectional view of the suspension board with circuit shown in FIG. 1 taken along the line AA. [Figure 3]Figures 3A to 3D show the manufacturing process of the suspension board with circuit shown in Figure 2, where Figure 3A shows the first insulating layer forming process, Figure 3B shows the circuit pattern forming process, Figure 3C shows the second insulating layer forming process, and Figure 3D shows the pedestal forming process. [Figure 4] Figure 4A is a plan view of the second base of modified example (1), Figure 4B is a plan view of the second base of modified example (2), Figure 4C is a plan view of the second base of modified example (3), and Figure 4D is a plan view of the second base of modified example (4). [Figure 5] 5A and 5B are plan views of the first and second bases of the modified example (5). DETAILED DESCRIPTION OF THE INVENTION

[0032] 1. Circuit-attached suspension board A suspension board with circuit 1 will be described as an example of a wired circuit board.

[0033] The suspension board with circuit 1 is one component that constitutes a head gimbal assembly of a hard disk drive.

[0034] As shown in FIG. 1 , the suspension board with circuit 1 can mount a slider S as an example of an electronic component. The slider S has a magnetic head. The suspension board with circuit 1 may also be capable of mounting two piezoelectric elements Pz1 and Pz2 in addition to the slider S. With the slider S and the two piezoelectric elements Pz1 and Pz2 mounted on the suspension board with circuit 1, the slider S is disposed between the piezoelectric elements Pz1 and Pz2 in the first direction. The slider S has a first end E1 and a second end E2 opposite to the first end E1. A magnetic head is disposed at the first end E1. The magnetic head can read data from and write data to the recording surface of a hard disk.

[0035] The suspension board with circuit 1 has a mounting portion 1A and a wiring portion 1B.

[0036] The mounting portion 1A is disposed at the tip of the suspension board with circuit 1. A slider S is mounted on the mounting portion 1A. If the suspension board with circuit 1 is capable of mounting piezoelectric elements Pz1, Pz2, the piezoelectric elements Pz1, Pz2 are also mounted on the mounting portion 1A. The mounting portion 1A is supported at the tip of the wiring portion 1B by outrigger portions (not shown). The mounting portion 1A extends in a first direction and a second direction. The first direction is the direction in which terminals 131A to 131G (described later) are aligned. The second direction is perpendicular to the first direction. The first and second directions are perpendicular to the thickness direction of a metal support layer 11 (described later).

[0037] The wiring portion 1B is disposed on the other side of the mounting portion 1A in the second direction. The wiring portion 1B extends in the second direction. The wiring portion 1B has a belt shape.

[0038] As shown in FIG. 2, the suspension board with circuit 1 includes a metal support layer 11, a first insulating layer 12, a circuit pattern 13 (see FIG. 1), a second insulating layer 14, and a plurality of pedestals 15A, 15B, 15C, and 15D (see FIG. 1).

[0039] (1) Metal support layer The metal support layer 11 supports the first insulating layer 12, the circuit pattern 13, the second insulating layer 14, and the plurality of pedestals 15A, 15B, 15C, and 15D. Examples of materials for the metal support layer 11 include stainless steel and copper alloys.

[0040] (2) First insulating layer The first insulating layer 12 is disposed between the metal support layer 11 and the circuit pattern 13 in the thickness direction. In other words, the first insulating layer 12 is disposed between the metal support layer 11 and the wiring pattern 133 described later in the thickness direction. The first insulating layer 12 insulates the metal support layer 11 from the circuit pattern 13. The first insulating layer 12 is made of a resin. Examples of resins include polyimide, maleimide, epoxy resin, polybenzoxazole, and polyester. The first insulating layer 12 is preferably made of polyimide. The first insulating layer 12 has through holes 12A, 12B, 12C, and 12D (see FIG. 1).

[0041] (3) Circuit pattern The circuit pattern 13 is disposed on one surface of the first insulating layer 12 in the thickness direction. The circuit pattern 13 is made of a metal. Examples of metals include copper, silver, gold, iron, aluminum, and alloys thereof. The circuit pattern 13 is preferably made of copper.

[0042] 1, the circuit pattern 13 includes a plurality of terminals 131A, 131B, 131C, 131D, 131E, 131F, and 131G, a plurality of terminals 132A, 132B, 132C, 132D, 132E, 132F, and 132G, and a wiring pattern 133. That is, the suspension board with circuit 1 includes a plurality of terminals 131A to 131G, a plurality of terminals 132A to 132G, and the wiring pattern 133. When the suspension board with circuit 1 is capable of mounting piezoelectric elements Pz1 and Pz2, the circuit pattern 13 further includes terminals 134A and 134B, terminals 135A and 135B, terminals 136A and 136B, and wirings 137A and 137B.

[0043] (3-1) Terminal The terminals 131A to 131G are arranged at one end of the mounting portion 1A in the second direction. The terminals 131A to 131G are aligned in the first direction. When the slider S is mounted on the suspension board with circuit 1, the terminals 131A to 131G are electrically connected to the magnetic head of the slider S.

[0044] (3-2) Terminal The terminals 132A to 132G are arranged on the wiring portion 1 B. The direction in which the terminals 132A to 132G are arranged is not limited.

[0045] (3-3) Wiring pattern 2, the wiring pattern 133 is disposed on one surface of the first insulating layer 12 in the thickness direction of the first insulating layer 12. When the slider S is mounted on the suspension board with circuit 1, the wiring pattern 133 overlaps with the slider S in the thickness direction. When the slider S is mounted on the suspension board with circuit 1, the wiring pattern 133 is electrically connected to the magnetic head of the slider S.

[0046] 1, the wiring pattern 133 has a plurality of first wirings 133A, 133B, 133C, and 133D, and a plurality of second wirings 133E, 133F, 133G, and 133H. The wiring pattern 133 also has a dummy wiring 133I.

[0047] The first wirings 133A to 133D overlap with the base 15A in the thickness direction. The first wirings 133A to 133D also overlap with the base 15C.

[0048] The first wiring 133A electrically connects the terminal 131A and the terminal 132A. One end of the first wiring 133A is connected to the terminal 131A. The first wiring 133A is a first connection wiring that is connected to one of the terminals 131A to 131G (terminal 131A). That is, the first wirings 133A to 133D include a first connection wiring. The other end of the first wiring 133A is connected to the terminal 132A.

[0049] The first wiring 133B electrically connects the terminal 131B and the terminal 132B. One end of the first wiring 133B is connected to the terminal 131B. The first wiring 133B is a first connection wiring that is connected to one of the terminals 131A to 131G (terminal 131B). The other end of the first wiring 133B is connected to the terminal 132B.

[0050] The first wiring 133C electrically connects the terminal 131C and the terminal 132C. One end of the first wiring 133C is connected to the terminal 131C. The first wiring 133C is a first connection wiring that is connected to one of the terminals 131A to 131G (terminal 131C). The other end of the first wiring 133C is connected to the terminal 132C.

[0051] The first wiring 133D electrically connects the terminal 131D and the terminal 132D. One end of the first wiring 133D is connected to the terminal 131D. The first wiring 133D is a first connection wiring that is connected to one of the terminals 131A to 131G (terminal 131D). In this embodiment, all of the first wirings 133A to 133D are first connection wirings. The other end of the first wiring 133D is connected to the terminal 132D.

[0052] The second wirings 133E to 133H overlap with the base 15B in the thickness direction. The second wirings 133E to 133G also overlap with the base 15D.

[0053] The second wiring 133E electrically connects the terminal 131E and the terminal 132E. One end of the second wiring 133E is connected to the terminal 131E. The second wiring 133E is a second connection wiring connected to one of the terminals 131A to 131G (terminal 131E). That is, the second wirings 133E to 133H include second connection wiring. The other end of the second wiring 133E is connected to the terminal 132E.

[0054] The second wiring 133F electrically connects the terminal 131F and the terminal 132F. One end of the second wiring 133F is connected to the terminal 131F. That is, the second wiring 133F is a second connection wiring connected to one of the terminals 131A to 131G (terminal 131F). The other end of the second wiring 133F is connected to the terminal 132F.

[0055] The second wiring 133G electrically connects the terminal 131G and the terminal 132G. One end of the second wiring 133G is connected to the terminal 131G. That is, the second wiring 133G is a second connection wiring that is connected to one of the terminals 131A to 131G (terminal 131G). The other end of the second wiring 133G is connected to the terminal 132G.

[0056] The second wiring 133H is a dummy wiring. That is, the second wirings 133E to 133H include dummy wiring. The second wiring 133H (dummy wiring) is not connected to any of the terminals 131A to 131G. The second wiring 133H (dummy wiring) is connected to the metal support layer 11 (see FIG. 2) through the through-hole 12A of the first insulating layer 12. Note that the second wiring 133H is not limited to being a dummy wiring. Any of the second wirings 133E to 133G may be a dummy wiring. Furthermore, the number of dummy wirings is not limited to one. Dummy wirings can be provided according to the number of second connection wirings that is insufficient compared to the first connection wirings.

[0057] Here, the number of second wirings 133E-133G (second connection wirings) connected to one of the terminals 131A-131G among the second wirings 133E-133H overlapping the base 15B is smaller than the number of first wirings 133A-133D (first connection wirings) connected to one of the terminals 131A-131G among the first wirings 133A-133D overlapping the base 15A. In this embodiment, the number of second connection wirings is three (second wirings 133E-133G), and the number of first connection wirings is four (first wirings 133A-133D).

[0058] In this regard, by adding the second wirings 133H (dummy wirings), the number of second wirings 133E to 133H overlapping the base 15B is the same as the number of first wirings 133A to 133D overlapping the base 15A. In this embodiment, the number of second wirings 133E to 133H is four, and the number of first wirings 133A to 133D is also four.

[0059] 2, the width W2 of each of the second wirings 133E to 133H is the same as the width W1 of each of the first wirings 133A to 133D. In other words, the width W2 of each of the second connection wirings (second wirings 133E to 133G) and the dummy wirings (second wiring 133H) is the same as the width W1 of each of the first connection wirings (first wirings 133A to 133D). Note that the width W2 being "the same" as the width W1 does not necessarily mean that the width W2 and the width W1 are completely identical. Even when the width W2 and the width W1 differ within the range of dimensional errors that inevitably occur in the manufacture of the suspension board with circuit 1, the width W2 is still "the same" as the width W1. Note that the difference between the width W1 and the width W2 caused by "dimensional errors that inevitably occur in the manufacture of the suspension board with circuit 1" is, for example, 5 μm or less, preferably 3 μm or less, and more preferably 1 μm or less.

[0060] Furthermore, the interval D2 between the second wirings 133E to 133H is the same as the interval D1 between the first wirings 133A to 133D. In other words, the interval D2 between the second connection wirings (second wirings 133E to 133G) and the interval D2 between the second connection wiring (second wiring 133G) and the dummy wiring (second wiring 133H) are the same as the interval D1 between the first connection wirings (first wirings 133A to 133D). Regarding the intervals D1 and D2, "the same" does not necessarily mean that the interval D2 and the interval D1 are completely the same. Even when the interval D2 and the interval D1 differ within the range of dimensional errors that inevitably occur in the manufacture of the suspension board with circuit 1, the interval D2 is "the same" as the interval D1. The difference between the gap D1 and the gap D2 caused by "a dimensional error that inevitably occurs in the manufacture of the suspension board with circuit 1" is, for example, 5 μm or less, preferably 3 μm or less, and more preferably 1 μm or less.

[0061] As shown in FIG. 1, the dummy wiring 133I overlaps the base 15D. The dummy wiring 133I is not connected to any of the terminals 131A to 131G. The dummy wiring 133I is connected to the metal support layer 11 through the through-hole 12B of the first insulating layer 12. With the addition of the dummy wiring 133I, the number of wirings overlapping the base 15D (i.e., the total number of the second wirings 133E to 133G and the dummy wirings 133I) is the same as the number of wirings overlapping the base 15C (i.e., the number of the first wirings 133A to 133D). Furthermore, the widths of the second wirings 133E to 133G and the dummy wiring 133I are the same as the widths of the first wirings 133A to 133D. The intervals between the second wirings 133E to 133G and the intervals between the second wirings 133G and the dummy wirings 133I are the same as the intervals between the first wirings 133A to 133D.

[0062] (3-4) Connection with piezoelectric element As shown in FIG. 1, the circuit pattern 13 further includes terminals 134A and 134B, terminals 135A and 135B, terminals 136A and 136B, and wirings 137A and 137B, which are electrically connected to the piezoelectric elements Pz1 and Pz2.

[0063] The terminal 134A is disposed on one side of the wiring pattern 133 in the first direction. When the piezoelectric element Pz1 is mounted on the mounting portion 1A, the terminal 134A is connected to one end of the piezoelectric element Pz1. The terminal 134A is connected to the metal support layer 11 (see FIG. 2) through the through-hole 12C of the first insulating layer 12.

[0064] The terminal 134B is disposed on the other side of the wiring pattern 133 in the first direction. When the piezoelectric element Pz2 is mounted on the mounting portion 1A, the terminal 134B is connected to one end of the piezoelectric element Pz2. The terminal 134B is connected to the metal support layer 11 (see FIG. 2) through the through-hole 12D of the first insulating layer 12.

[0065] The terminal 135A is disposed away from the terminal 134A in the second direction. The terminal 135A is disposed on one side of the wiring pattern 133 in the first direction. When the piezoelectric element Pz1 is mounted on the mounting portion 1A, the terminal 135A is connected to the other end of the piezoelectric element Pz1.

[0066] Terminal 135B is disposed away from terminal 134B in the second direction. Terminal 135B is disposed on the other side of wiring pattern 133 in the first direction. When piezoelectric element Pz2 is mounted on mounting portion 1A, terminal 135B is connected to the other end of piezoelectric element Pz2.

[0067] The terminals 136A and 136B are arranged on the wiring portion 1B. The terminals 136A and 136B are aligned with the terminals 132A to 132G.

[0068] The wiring 137A electrically connects the terminal 135A and the terminal 136A. One end of the wiring 137A is connected to the terminal 135A. The other end of the wiring 137A is connected to the terminal 136A.

[0069] The wiring 137B electrically connects the terminal 135B and the terminal 136B. One end of the wiring 137B is connected to the terminal 135B. The other end of the wiring 137B is connected to the terminal 136B.

[0070] (4) Second insulating layer As shown in FIG. 2, the second insulating layer 14 is disposed on one surface of the first insulating layer 12 in the thickness direction. The second insulating layer 14 covers the wiring pattern 133 and the wirings 137A and 137B (see FIG. 1). That is, the second insulating layer 14 covers the first wirings 133A to 133D and the second wirings 133E to 133H at the locations where the pedestals 15A and 15B are formed, respectively. The second insulating layer 14 does not cover the terminals 131A to 131G, 132A to 132G, the terminals 134A and 134B, the terminals 135A and 135B, and the terminals 136A and 136B. The second insulating layer 14 is made of a resin. Examples of the resin include the same resin as that of the first insulating layer 12. The second insulating layer 14 is preferably made of polyimide.

[0071] As described above, the number of wirings overlapping the base 15B (that is, the number of second wirings 133E to 133H) is the same as the number of wirings overlapping the base 15A (that is, the number of first wirings 133A to 133D).

[0072] Furthermore, the width W2 of each of the second wirings 133E to 133H is the same as the width W1 of each of the first wirings 133A to 133D, and the interval D2 between the second wirings 133E to 133H is the same as the interval D1 between the first wirings 133A to 133D.

[0073] Therefore, the thickness T2 of the second insulating layer 14 overlapping the base 15B is the same as the thickness T1 of the second insulating layer 14 overlapping the base 15A. Note that the thicknesses T1 and T2 are the thicknesses T1 and T2 of the second insulating layer 14 on the surface on one side of the wiring pattern 133 in the thickness direction. Furthermore, "the same" does not necessarily mean that the thickness T2 and the thickness T1 are completely the same. Even when the thicknesses T2 and T1 differ within the range of dimensional errors that inevitably occur during the manufacture of the suspension board with circuit 1, the thickness T2 is "the same" as the thickness T1.

[0074] (5) Base The pedestals 15A, 15B, 15C, and 15D are disposed on one surface of the second insulating layer 14 in the thickness direction. When the slider S is mounted on the suspension board with circuit 1, the pedestals 15A, 15B, 15C, and 15D support the slider S. The pedestals 15A, 15B, 15C, and 15D are made of resin. Examples of the resin include the same resin as that of the first insulating layer 12. The pedestals 15A, 15B, 15C, and 15D are preferably made of polyimide. Each of the pedestals 15A, 15B, 15C, and 15D has a substantially rectangular sheet shape (see FIG. 1). The shape of each of the pedestals 15A, 15B, 15C, and 15D is not limited.

[0075] The base 15A is disposed on one side of the first wirings 133A to 133D in the thickness direction. The base 15A covers the first wirings 133A to 133D in the thickness direction.

[0076] The base 15B is disposed on one side of the second wirings 133E to 133H in the thickness direction. The base 15B covers the second wirings 133E to 133H in the thickness direction. The base 15B is disposed apart from the base 15A in the first direction.

[0077] 1, base 15C is disposed on the other side of base 15A in the second direction. Base 15C is disposed away from base 15A in the second direction. Base 15C is disposed on one side of first wirings 133A to 133D in the thickness direction. Base 15A covers first wirings 133A to 133D in the thickness direction.

[0078] The pedestal 15D is disposed on the other side of the pedestal 15B in the second direction. The pedestal 15D is disposed away from the pedestal 15B in the second direction. The pedestal 15D is disposed away from the pedestal 15C in the first direction. The pedestal 15D is disposed on one side of the second wirings 133E to 133G and the dummy wirings 133I in the thickness direction. The pedestal 15D covers the second wirings 133E to 133G and the dummy wirings 133I in the thickness direction.

[0079] As shown in FIG. 2 and described above, the number of wirings overlapping base 15B (ie, the number of second wirings 133E to 133H) is the same as the number of wirings overlapping base 15A (ie, the number of first wirings 133A to 133D).

[0080] Furthermore, the width W2 of each of the second wirings 133E to 133H is the same as the width W1 of each of the first wirings 133A to 133D, and the interval D2 between the second wirings 133E to 133H is the same as the interval D1 between the first wirings 133A to 133D.

[0081] Therefore, the thickness T12 of the base 15B is the same as the thickness T11 of the base 15A. Note that the thicknesses T11 and T12 are the thicknesses T11 and T12 of the portions that overlap with the wiring pattern 133 in the thickness direction. Furthermore, "the same" does not necessarily mean that the thickness T12 and the thickness T11 are completely the same. Even if the thickness T12 and the thickness T11 differ within the range of dimensional errors that inevitably occur during the manufacture of the suspension board with circuit 1, the thickness T12 is "the same" as the thickness T11.

[0082] 2. Manufacturing method of suspension board with circuit 1 Next, a method for manufacturing the suspension board with circuit 1 will be described.

[0083] The method for manufacturing the suspension board with circuit 1 includes a first insulating layer forming step (see FIG. 3A), a circuit pattern forming step (see FIG. 3B), a second insulating layer forming step (see FIG. 3C), and a base forming step (see FIG. 3D).

[0084] (1) Insulation layer formation process 3A, in the first insulating layer forming step, the first insulating layer 12 is formed on a metal base material M. The metal base material M is the material of the metal support layer 11.

[0085] Specifically, first, a solution (varnish) of a photosensitive resin is applied onto the substrate M and dried to form a coating film of the photosensitive resin.

[0086] Next, the photosensitive resin coating is exposed to light and developed, thereby forming the first insulating layer 12 on the base material M.

[0087] (2) Circuit pattern formation process Next, as shown in FIG. 3B, in the circuit pattern forming step, a circuit pattern 13 is formed on the first insulating layer 12.

[0088] More specifically, in the circuit pattern forming step, a seed layer is first formed on one surface of the first insulating layer 12 and one surface of the substrate M in the thickness direction. The seed layer is formed by, for example, sputtering. Examples of materials for the seed layer include chromium, copper, nickel, titanium, and alloys thereof.

[0089] Next, a plating resist is attached to one surface of the base material M in the thickness direction. The plating resist covers the first insulating layer 12.

[0090] Next, the plating resist is exposed to light and developed, which removes the plating resist from the area where the circuit pattern 13 is to be formed, exposing the seed layer in the area where the circuit pattern 13 is to be formed. On the other hand, the plating resist remains in the area where the circuit pattern 13 is not to be formed.

[0091] Next, a circuit pattern 13 is formed on the exposed seed layer by electrolytic plating. After the electrolytic plating is completed, the plating resist is stripped off. Thereafter, the seed layer exposed by the stripping of the plating resist is removed by etching.

[0092] (3) Second insulating layer formation process Next, as shown in FIG. 3C, in the second insulating layer forming step, second insulating layer 14 is formed on first insulating layer 12.

[0093] The second insulating layer 14 is formed in the same manner as the first insulating layer 12. More specifically, in the second insulating layer forming step, first, a solution (varnish) of a photosensitive resin (for example, photosensitive polyimide) is applied onto the first insulating layer 12, the substrate M, and the circuit pattern 13.

[0094] At this time, the varnish applied onto the circuit pattern 13 is applied to one surface in the thickness direction of the wirings (first wirings 133A to 133D and second wirings 133E to 133H), and also flows into the spaces between the wirings.

[0095] Here, when the width and spacing of the wiring are different, the thickness of the varnish on one side surface in the thickness direction of the wiring will differ. The narrower the wiring width, the thinner the varnish on one side surface in the thickness direction of the wiring will tend to be, and the wider the spacing between the wirings, the thinner the varnish on one side surface in the thickness direction of the wiring will tend to be.

[0096] In this regard, as described above, the number of second wirings 133E to 133H is the same as the number of first wirings 133A to 133D, the width W2 of each of second wirings 133E to 133H is the same as the width W1 of each of first wirings 133A to 133D, and the spacing D2 between second wirings 133E to 133H is the same as the spacing D1 between first wirings 133A to 133D.

[0097] Therefore, the thickness of the varnish on one surface in the thickness direction of the first wirings 133A to 133D is approximately the same as the thickness of the varnish on one surface in the thickness direction of the second wirings 133E to 133H.

[0098] The varnish is then dried to form a coating film of the photosensitive resin.

[0099] Next, the photosensitive resin coating is exposed to light and developed, thereby forming the second insulating layer 14 on the first insulating layer 12 as a cured product of the photosensitive resin.

[0100] (4) Base formation process Next, as shown in FIG. 3D, in the pedestal formation step, pedestals 15A, 15B, 15C, and 15D are formed on the second insulating layer 14 in the same manner as the second insulating layer 14.

[0101] More specifically, in the pedestal forming step, first, a solution (varnish) of a photosensitive resin (for example, photosensitive polyimide) is applied onto the first insulating layer 12, the base material M, and the second insulating layer .

[0102] At this time, the varnish applied onto the second insulating layer 14 is applied to one surface in the thickness direction of the second insulating layer 14, and also flows into between the wirings (first wirings 133A to 133D and second wirings 133E to 133H).

[0103] In this regard, the number of second wirings 133E to 133H is the same as the number of first wirings 133A to 133D, the width W2 of each of the second wirings 133E to 133H is the same as the width W1 of each of the first wirings 133A to 133D, and the spacing D2 between the second wirings 133E to 133H is the same as the spacing D1 between the first wirings 133A to 133D.

[0104] Therefore, the thickness of the varnish on one surface in the thickness direction of the second insulating layer 14 covering the first wirings 133A to 133D is approximately the same as the thickness of the varnish on one surface in the thickness direction of the second insulating layer 14 covering the second wirings 133E to 133H.

[0105] The varnish is then dried to form a coating film of the photosensitive resin.

[0106] Next, the photosensitive resin coating is exposed to light and developed, thereby forming the pedestals 15A, 15B, 15C, and 15D on the second insulating layer 14 as a cured product of the photosensitive resin.

[0107] Thereafter, the substrate M is etched to form the metal support layer 11 and outrigger portions (not shown).

[0108] In this way, the suspension board with circuit 1 is obtained.

[0109] 3. Effects (1) According to the suspension board with circuit 1, as shown in FIG. 2, the width W2, spacing D2 and number (specifically, 4) of the second wirings 133E to 133H that overlap the base 15B are the same as the width W1, spacing D1 and number (specifically, 4) of the first wirings 133A to 133D that overlap the base 15A.

[0110] Therefore, it is possible to prevent the thickness T11 of the base 15A and the thickness T12 of the base 15B from becoming different from each other.

[0111] More specifically, in the manufacture of the suspension board with circuit 1, when the second insulating layer 14 is formed, a photosensitive resin solution (varnish) is applied to the circuit pattern 13.

[0112] At this time, the varnish applied to the circuit pattern 13 is applied to one surface in the thickness direction of the wirings (first wirings 133A to 133D and second wirings 133E to 133H), and also flows into the spaces between the wirings.

[0113] Here, if the width W2, spacing D2 and number of the second wirings 133E to 133H are the same as the width W1, spacing D1 and number of the first wirings 133A to 133D, the thickness of the varnish on one surface in the thickness direction of the first wirings 133A to 133D can be made approximately the same as the thickness of the varnish on one surface in the thickness direction of the second wirings 133E to 133H.

[0114] Therefore, thickness T2 of second insulating layer 14 overlapping base 15B is approximately the same as thickness T1 of second insulating layer 14 overlapping base 15A.

[0115] Similarly, when forming the bases 15A, 15B on the second insulating layer 14, if the width W2, spacing D2 and number of the second wirings 133E-133H are the same as the width W1, spacing D1 and number of the first wirings 133A-133D, the thickness of the varnish on one surface in the thickness direction of the second insulating layer 14 that overlaps the first wirings 133A-133D can be made approximately the same as the thickness of the varnish on one surface in the thickness direction of the second insulating layer 14 that overlaps the second wirings 133E-133H.

[0116] Therefore, the thickness T12 of the base 15B is approximately the same as the thickness T11 of the base 15A.

[0117] Therefore, it is possible to prevent the thickness T11 of the base 15A and the thickness T12 of the base 15B from becoming different from each other.

[0118] (2) According to the suspension board with circuit 1, as shown in Fig. 1, the first wirings 133A to 133D are first connection wirings connected to one of the terminals 131A to 131G, and the second wirings 133E to 133G among the second wirings 133E to 133H are second connection wirings connected to one of the terminals 131A to 131G. The number of the second connection wirings (specifically, 3) is smaller than the number of the first connection wirings (specifically, 4).

[0119] In this regard, even if the number of first connection wirings (first wirings 133A to 133D) overlapping the base 15A is different from the number of second connection wirings (second wirings 133E to 133G) overlapping the base 15B, as shown in FIG. 2, the width W2, spacing D2 and number of the second wirings 133E to 133H are the same as the width W1, spacing D1 and number of the first wirings 133A to 133D.

[0120] Therefore, it is possible to prevent the thickness T11 of the base 15A and the thickness T12 of the base 15B from becoming different from each other.

[0121] (3) According to the suspension board with circuit 1, as shown in FIG. 1, of the second wirings 133E to 133H, the second wiring 133H is a dummy wiring that is not connected to any of the terminals 131A to 131G.

[0122] As a result, even if the number of second connection wirings is less than the number of first connection wirings, as shown in FIG. 2, by adding dummy wirings (second wirings 133H), the width W2, spacing D2 and number of the second wirings 133E to 133H can be matched with the width W1, spacing D1 and number of the first wirings 133A to 133D.

[0123] Therefore, by using the dummy wiring (second wiring 133H), it is possible to prevent the thickness T11 of the base 15A and the thickness T12 of the base 15B from becoming different from each other.

[0124] Furthermore, the dummy wiring (second wiring 133H) is not connected to any of the terminals 131A to 131G and is independent from the second wirings 133E to 133G. Therefore, for example, by measuring the resistance value between the terminal 131G and the metal support layer 11, a short circuit between the dummy wiring (second wiring 133H) and the second wiring 133G can be detected. Specifically, one probe is brought into contact with the terminal 131G and the other probe is brought into contact with the metal support layer 11. If the dummy wiring (second wiring 133H) and the second wiring 133G are short-circuited, the resistance value will be low, and it can be determined that the dummy wiring (second wiring 133H) and the second wiring 133G are short-circuited.

[0125] (4) As shown in FIG. 1, the suspension board with circuit 1 can mount a slider S having a magnetic head.

[0126] As described above, in the suspension board with circuit 1, the thickness T11 of the base 15A and the thickness T12 of the base 15B are prevented from becoming different from each other.

[0127] Therefore, the slider S can be prevented from being mounted at an angle relative to the suspension board with circuit 1.

[0128] 4. Variations In the modified example, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0129] (1) As shown in Fig. 4A, the second wiring 133H may be a branch wiring branched from the second wiring 133G. That is, the second wirings 133E to 133H may include branch wiring branched from the second connection wiring.

[0130] According to this modification, even if the number of second connection wirings is smaller than the number of first connection wirings, by adding branch wirings (second wirings 133H), the width W2, spacing D2 and number of the second wirings 133E to 133H can be matched with the width W1, spacing D1 and number of the first wirings 133A to 133D.

[0131] Therefore, in this modified example, similarly to the above-described embodiment, it is possible to prevent the thickness T11 of the base 15A and the thickness T12 of the base 15B from becoming different from each other.

[0132] 4B, the second wiring 133F may be a branch wiring branched from the second wiring 133E, and the second wiring 133H may be a branch wiring branched from the second wiring 133G. That is, the second wirings 133E to 133H may include one second connection wiring (second wiring 133E), another second connection wiring (second wiring 133G) independent from the one second connection wiring, a first branch wiring (second wiring 133F) branched from the one second connection wiring (second wiring 133E), and a second branch wiring (second wiring 133H) branched from the other second connection wiring (second wiring 133G).

[0133] In this modification, among the second wirings 133E to 133H, the number of second wirings 133E, 133G (second connection wirings) connected to one of the terminals 131A to 131G is two, and among the first wirings 133A to 133D, the number of wirings (first connection wirings) connected to one of the terminals 131A to 131G is four (see Figure 2).

[0134] Furthermore, the distance D10 between the second wirings 133E and 133G is greater than the distance D1 (see FIG. 2) between the first wirings 133A to 133D.

[0135] In this regard, by adding the first branch wiring (second wiring 133F) and the second branch wiring (second wiring 133H), not only can the number of second wirings 133E to 133H be matched to the number of first wirings 133A to 133D, but the spacing D2 between the second wirings 133E to 133H can also be matched to the spacing D1 between the first wirings 133A to 133D.

[0136] Specifically, the first branch wiring (second wiring 133F) is disposed between one second connection wiring (second wiring 133E) and another second connection wiring (second wiring 133G). The second branch wiring (second wiring 133H) is disposed on the opposite side of the first branch wiring (second wiring 133F) with respect to the other second connection wiring (second wiring 133G).

[0137] The distance D2 between one second connection wiring (second wiring 133E) and the first branch wiring (second wiring 133F), the distance D2 between the first branch wiring (second wiring 133F) and another second connection wiring (second wiring 133G), and the distance D2 between the other second connection wiring (second wiring 133G) and the second branch wiring (second wiring 133H) are all the same as the distance D1 (see Figure 2) between the first wirings 133A to 133D.

[0138] According to this modification, even if the number of second connection wirings is smaller than the number of first connection wirings and the spacing between the second connection wirings is wider than the spacing between the first connection wirings, by adding a first branch wiring (second wiring 133F) and a second branch wiring (second wiring 133H), the width W2, spacing D2 and number of the second wirings 133E to 133H can be matched with the width W1, spacing D1 and number of the first wirings 133A to 133D.

[0139] Therefore, in this modified example, similarly to the above-described embodiment, it is possible to prevent the thickness T11 of the base 15A and the thickness T12 of the base 15B from becoming different from each other.

[0140] 4C, the second wiring 133G may be a branch wiring branched from the second wiring 133E, and the second wiring 133F may be a branch wiring branched from the second wiring 133H. That is, the second wirings 133E to 133H may include one second connection wiring (second wiring 133E), another second connection wiring (second wiring 133H) independent from the one second connection wiring, a first branch wiring (second wiring 133G) branched from the one second connection wiring (second wiring 133E), and a second branch wiring (second wiring 133F) branched from the other second connection wiring (second wiring 133H).

[0141] In this modification, among the second wirings 133E to 133H, the number of second wirings 133E, 133H (second connection wirings) connected to one of the terminals 131A to 131G is two, and among the first wirings 133A to 133D, the number of wirings (first connection wirings) connected to one of the terminals 131A to 131G is four (see Figure 2).

[0142] Furthermore, the distance D20 between the second wiring 133E and the second wiring 133H is greater than the distance D1 (see FIG. 2) between the first wirings 133A to 133D.

[0143] The first branch wiring (second wiring 133G) is arranged between one second connection wiring (second wiring 133E) and another second connection wiring (second wiring 133H), and the second branch wiring (second wiring 133F) is arranged between the first branch wiring (second wiring 133G) and one second connection wiring (second wiring 133E).

[0144] The distance D2 between one second connection wiring (second wiring 133E) and the second branch wiring (second wiring 133F), the distance D2 between the second branch wiring (second wiring 133F) and the first branch wiring (second wiring 133G), and the distance D2 between the first branch wiring (second wiring 133G) and another second connection wiring (second wiring 133H) are all the same as the distance D1 (see Figure 2) between the first wirings 133A to 133D.

[0145] In this modification, similarly to the above-described modification (2), it is possible to prevent the thickness T11 of the base 15A and the thickness T12 of the base 15B from becoming different from each other.

[0146] 4D, the wiring pattern 133 may further include a third wiring 130 that does not overlap with either the base 15A or the base 15B in the thickness direction. The second wirings 133E to 133H may include a branch wiring (second wiring 133H) branching from the third wiring 130.

[0147] According to this modification, even if the number of second connection wirings is smaller than the number of first connection wirings, by adding a branch wiring (second wiring 133H) from the third wiring 130 that does not overlap with either the base 15A or the base 15B, the width W2, spacing D2 and number of the second wirings 133E to 133H can be matched with the width W1, spacing D1 and number of the first wirings 133A to 133D.

[0148] Therefore, in this modified example as well, it is possible to prevent the thickness T11 of the base 15A and the thickness T12 of the base 15B from becoming different from each other.

[0149] (5) The width of the second wirings 133E to 133H may be different from the width of the first wirings 133A to 133D.

[0150] For example, as shown in FIG. 5A, the width W10 (width W10 of the portion not overlapping with the pedestal 15B) of the second wiring 133H (in other words, at least one of the second wirings 133E to 133H) may be larger than the width W1 of the first wirings 133A to 133D. In this case, the width W2 of the portion of the second wiring 133H that overlaps with the pedestal 15B is matched to the width W1 of the first wirings 133A to 133D. In other words, in the portion that overlaps with the pedestal 15B, the width W2 of the second wirings 133E to 133H is the same as the width W1 of the first wirings 133A to 133D.

[0151] 5B, the width W11 of the first wiring 133A (in other words, at least one of the first wirings 133A to 133D) may be larger than the width W2 of the second wirings 133E to 133G. In this case, the width W12 of the portion of the second wiring 133H that overlaps with the base 15B is made to match the width W11 of the first wiring 133A. In other words, in the portion that overlaps with the base 15B, the width W2 of the second wirings 133E to 133G is the same as the width W1 of the first wirings 133B to 133D, and the width W11 of the first wiring 133A is the same as the width W12 of the second wiring 133H.

[0152] Even in this modified example, it is possible to prevent the thickness T11 of the base 15A and the thickness T12 of the base 15B from becoming different from each other. [Explanation of symbols]

[0153] 1. Circuit-equipped suspension board (an example of a wiring circuit board) 11 Metal support layer 12 First insulating layer 12A through hole 14 Second insulating layer 15A Pedestal (example of the first pedestal) 15B Pedestal (Example of second pedestal) 131A~131G terminals 133 Wiring Pattern 133A~133D 1st wiring 133E~133H Second wiring D1 First wiring spacing D2 Second wiring spacing S Slider (an example of an electronic component) W1 Width of the first wiring W2 Width of the second wiring 130 3rd wiring

Claims

1. A printed circuit board on which electronic components can be mounted, a first insulating layer; a wiring pattern disposed on the first insulating layer in a thickness direction of the first insulating layer, and overlapping with the electronic component in the thickness direction when the electronic component is mounted on the printed circuit board; a second insulating layer disposed on the first insulating layer in the thickness direction and covering the wiring pattern; a first base that is disposed on the second insulating layer in the thickness direction and that supports the electronic component when the electronic component is mounted on the printed circuit board; a second seat that is disposed on the second insulating layer in the thickness direction and spaced apart from the first seat in the first direction, and that supports the electronic component when the electronic component is mounted on the wired circuit board; Equipped with The wiring pattern is a plurality of first wirings overlapping the first seat in the thickness direction; a plurality of second wirings overlapping the second seat in the thickness direction; and the width of each of the plurality of second wirings is the same as the width of each of the plurality of first wirings; The spacing between the plurality of second wirings is the same as the spacing between the plurality of first wirings, and The number of the plurality of second wirings is the same as the number of the plurality of first wirings.

2. The printed circuit board is a plurality of terminals that are electrically connected to the electronic component when the electronic component is mounted on the printed circuit board; the plurality of first wirings include a first connection wiring connected to one of the plurality of terminals, The printed circuit board according to claim 1 , wherein the plurality of second wirings includes a second connection wiring connected to one of the plurality of terminals.

3. The printed circuit board according to claim 2 , wherein the number of said second connection wires is smaller than the number of said first connection wires.

4. 4. The printed circuit board according to claim 2, wherein the plurality of second wirings include dummy wirings that are not connected to any of the plurality of terminals.

5. The printed circuit board further includes a metal support layer, the first insulating layer is disposed between the metal support layer and the wiring pattern in the thickness direction, and has a through hole; The printed circuit board according to claim 4 , wherein the dummy wiring is connected to the metal support layer through the through hole of the first insulating layer.

6. 4. The printed circuit board according to claim 2, wherein the plurality of second wirings include branch wirings branched from the second connection wiring.

7. The plurality of second wirings are one of the second connection wirings; another second connection wiring that is independent from the one second connection wiring; a first branch wiring branched from the one second connection wiring; a second branch wiring branched from the other second connection wiring; and The wired circuit board according to claim 2 or claim 3, comprising:

8. the first branch wiring is disposed between the one second connection wiring and the other second connection wiring, The printed circuit board according to claim 7 , wherein the second branch wiring is disposed on an opposite side of the other second connection wiring from the first branch wiring.

9. the first branch wiring is disposed between the one second connection wiring and the other second connection wiring, The printed circuit board according to claim 7 , wherein the second branch wiring is disposed between the first branch wiring and the one second connection wiring.

10. The wiring pattern is a third wiring that does not overlap with either the first seat or the second seat in the thickness direction; 4. The printed circuit board according to claim 2, wherein the plurality of second wirings include branch wirings branched from the third wiring.

11. 2. The printed circuit board according to claim 1, wherein the electronic component is a slider having a magnetic head.

Images