Wired circuit board having one of the conductive layers disposed in an opening formed in metal supporting board

A wired circuit board includes a metal pedestal portion formed from a metal material that is the same as the material of the metal supporting board at the pad portion, a pedestal opening formed by opening the metal pedestal portion, a lower conductive layer disposed on one side in the thickness direction of the metal pedestal portion as the first conductive layer, and an upper conductive layer as the second conductive layer formed on one side in the thickness direction of the lower conductive layer as the first conductive layer, wherein one of the lower conductive layer as the first conductive layer and the upper conductive layer as the second conductive layer is disposed in the pedestal opening when projected in the thickness direction, and the periphery of the other is disposed outside of the pedestal opening when projected in the thickness direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a 35 U.S.C. 371 National Stage Entry of PCT/JP2015/058472, filed on Mar. 20, 2015, which claims priority from Japanese Patent Application No. 2014-087046, filed on Apr. 21, 2014, the contents of both of which are herein incorporated by reference in their entirety.

TECHNICAL FIELD

The present invention relates to a wired circuit board. In particular, the present invention relates to a wired circuit board used for hard disk drives.

BACKGROUND ART

Conventionally, a substrate for suspension including a metal supporting board, a first insulating layer formed on the metal supporting board, a first wire layer formed on the first insulating layer, a second insulating layer formed on the first wire layer, and a second wire layer formed on the second insulating layer has been known.

For such a substrate for suspension, a substrate for suspension including a metal supporting board having a metal supporting board opening, and a flying lead terminal formed at the metal supporting board opening for connecting with an external circuit board is known (ref: e.g., Patent Document 1).

When the substrate for suspension is projected in the thickness direction, the end portion of the metal supporting board opening overlaps with the first wire layer and the second wire layer. In this fashion, for example, when producing the substrate for suspension, breakage of the first wire layer and the second wire layer is suppressed when stress is concentrated on the end portion of the metal supporting board opening.

CITATION LIST

Patent Document

SUMMARY OF THE INVENTION

Problem to be Solved by the Invention

However, in the substrate for suspension described in Patent Document 1 above, the end portion of the metal supporting board opening overlaps with the first wire layer and the second wire layer when projected in the thickness direction, and therefore it is disadvantageous in that flexibility is difficult to ensure. Therefore, it is disadvantageous in that impacts applied to the substrate for suspension are difficult to be alleviated.

An object of the present invention is to provide a wired circuit board in which damages to the first conductive layer and the second conductive layer can be suppressed, and impacts can be alleviated.

Means for Solving the Problem

A wired circuit board of the present invention includes a metal supporting board having an opening, a first conductive layer disposed on one side in the thickness of the direction of the metal supporting board, and a second conductive layer disposed on one side in the thickness direction of the first conductive layer, wherein one of the first conductive layer and the second conductive layer is disposed in the opening when projected in the thickness direction, and the periphery of the other of the first conductive layer and the second conductive layer is disposed outside of the opening when projected in the thickness direction.

In such a wired circuit board, one of the first conductive layer and the second conductive layer is disposed in the opening when projected in the thickness direction, and the periphery of the other of the first conductive layer and the second conductive layer is disposed outside the opening when projected in the thickness direction.

Therefore, the first conductive layer and the second conductive layer can be disposed in line in the thickness direction, and strength of the first conductive layer and the second conductive layer can be increased.

As a result, damages to the first conductive layer and the second conductive layer can be suppressed.

One of the first conductive layer and the second conductive layer is disposed in the opening when projected in the thickness direction. That is, in the thickness direction, one of the first conductive layer and the second conductive layer does not overlap with the opening.

Therefore, flexibility of the wired circuit board can be ensured, and impacts applied to the wired circuit board can be alleviated.

The periphery of the other of the first conductive layer and the second conductive layer is disposed outside the opening when projected in the thickness direction.

Therefore, strength of the wired circuit board can be ensured.

In the wired circuit board of the present invention, it is preferable that the first conductive layer is disposed in the opening when projected in the thickness direction, and the periphery of the second conductive layer is disposed outside the opening when projected in the thickness direction.

In such a wired circuit board, the first conductive layer is disposed in the opening when projected in the thickness direction.

Therefore, impacts in proximity of the opening can be alleviated.

In the wired circuit board of the present invention, it is preferable that at least a portion of one side face of the first conductive layer in the thickness direction is in contact with the second conductive layer.

With such a wired circuit board, strength of the first conductive layer and the second conductive layer can be further increased at the portion where the first conductive layer contacts the second conductive layer.

In the wired circuit board of the present invention, it is preferable that the first conductive layer is disposed so as to be in spaced-apart relation from the second conductive layer in the thickness direction.

With such a wired circuit board, flexibility of the wired circuit board can further be ensured, and impacts applied on the wired circuit board can further be alleviated.

Effects of the Invention

With the wired circuit board of the present invention, damages to the first conductive layer and the second conductive layer can be suppressed, and impacts can be alleviated.

DESCRIPTION OF EMBODIMENTS

InFIG. 1, the left-right direction on the plane of the paper is referred to as head-tail direction (first direction), the left side on the plane of the sheet is head-side (one side in the first direction), and the right side on the plane of the sheet is tail-side (the other side in the first direction). InFIG. 1, the up-down direction on the plane of the paper is referred to as left-right direction (width direction, second direction perpendicular to the first direction), the upper side on the plane of the sheet is left side (one side in the width direction, one side in the second direction), and the lower side on the plane of the paper is right side (the other side in the width direction, the other side in the second direction). InFIG. 1, the paper thickness direction on the plane of the paper is referred to as up-down direction (thickness direction, third direction perpendicular to the first direction and the second direction), the front side to the plane of the paper is upper side (one side in the thickness direction, one side in the third direction), the rear side to the plane of the paper is lower side (the other side in the thickness direction, the other side in the third direction). To be specific, directions are in conformity with the direction arrows in each of the figures.

1. Whole Structure of Assembly

An assembly1is, as shown inFIGS. 1 and 2, a head stack assembly (HSA), which is mounted in a hard disk drive (not shown): in the assembly1, a support plate2supports a suspension board with circuits3as a wired circuit board on which a slider22mounting a magnetic head100and a piezoelectric element5as an electron device are mounted. The assembly1includes the support plate2, and a suspension board with circuits3provided on the support plate2and supported by the support plate2.

InFIG. 1, an insulating base layer28, an intermediate insulating layer30, and an insulating cover layer29to be described later are omitted to clearly show relative positions of a conductive layer19to be described later.

The support plate2is formed to extend in the head-tail direction, and includes an actuator plate portion6, a base plate portion7provided below the actuator plate portion6, and a load beam portion8provided continuously at the head-side of the actuator plate portion6.

The actuator plate portion6integrally includes a tail-plate portion9, a head-plate portion10provided at the head-side of the tail-plate portion9in spaced-apart relation, and a flexible portion11provided between the tail-plate portion9and the head-plate portion10.

The tail-plate portion9is formed into a generally rectangular shape when viewed from the top at the tail end portion of the actuator plate portion6.

The head-plate portion10is formed into a generally rectangular shape when viewed from the top extending in left-right direction.

The flexible portion11is provided at both left and right sides of the actuator plate portion6. The right side flexible portion11is provided so as to bridge the right side portion of the head end portion of the tail-plate portion9and the right side portion of the tail end portion of the head-plate portion10. The left side flexible portion11is provided so as to bridge the left side portion of the head end portion of the tail-plate portion9and the left side portion of the tail end portion of the head-plate portion10. Center portions in the head-tail direction of the two flexible portions11are bent toward both left and right outer sides, and are formed to be about the same width in the head-tail direction. To be specific, the center portion in the head-tail direction of the flexible portion11is formed to project in both left and right outer sides to have a generally letter U shape (or generally letter V shape). Therefore, the flexible portion11is configured so that the contraction of the piezoelectric element5allows for the head-plate portion10to go away and come close relative to the tail-plate portion9, which is to be described later.

The actuator plate portion6is provided with a plate opening12that is defined by the head-face of the tail-plate portion9, the tail-face of the head-plate portion10, and the inner-face in left-right direction of the flexible portion11. The plate opening12penetrates the actuator plate portion6in the thickness direction.

At a head end portion of the tail-plate portion9and a tail end portion of the head-plate portion10, two pairs of attachment regions13are defined for the tail end portion and the head end portion of the piezoelectric element5to be attached. Each of the two pairs of attachment regions13is formed into a generally rectangular shape when viewed from the bottom extending in the head-tail direction, corresponding to the head end portion of the tail-plate portion9and the tail end portion of the head-plate portion10at the left side portion and the right side portion.

The base plate portion7is fixed at a center portion in left-right direction and a center portion in the head-tail direction at the lower face of the tail-plate portion9. The head portion of the base plate portion7is formed into a generally rectangular shape and the tail portion of the base plate portion7is formed into a semicircular shape when viewed from the top.

The support plate2is provided with a hole14having a generally circular shape when viewed from the bottom, the hole14penetrating a center portion of the tail-plate portion9and a center portion of the base plate portion7in the thickness direction.

To the base plate portion7, a driving coil (not shown) is attached for swinging the head end portion of the assembly1with the hole14as the center.

The load beam portion8is provided integrally with the actuator plate portion6; to be specific, the load beam portion8is formed to extend from the distal end of the head-plate portion10to the head-side, and is formed to have a generally trapezoid shape decreasing its width towards the head-side when viewed from the top.

The support plate2is formed from, for example, metal materials such as stainless steel, aluminum, iron, and alloys thereof. The size of the support plate2is suitably adjusted, and the size is as follows: for example, the actuator plate portion6and the load beam portion8have a thickness of, for example, 30 μm or more, and for example, 150 μm or less, and the base plate portion7has a thickness of, for example, 150 μm or more, and for example, 200 μm or less. The support plate2is an actuator plate load beam integrated plate integrally including an actuator plate portion6and a load beam portion8.

2. Suspension Board with Circuits

(2-1) General Structure of Suspension Board with Circuits

The suspension board with circuits3is formed into a generally flat belt shape extending in the head-tail direction when viewed from the top. The suspension board with circuits3is provided with, as shown inFIG. 1, a metal supporting board18and a conductive layer19supported by the metal supporting board18.

The metal supporting board18is formed to correspond to the outline shape of the suspension board with circuits3, and integrally includes a wire portion16, a head portion15provided at the head-side of the wire portion16, and a tail portion17provided at the tail-side of the wire portion16.

The wire portion16is formed at a center portion in the head-tail direction of the metal supporting board18, and integrally includes a linear portion20extending into the head-tail direction, and a bending portion21bending from the tail end portion of the linear portion20to the left side, and then bending to the tail-side. The linear portion20and the bending portion21are formed to have the generally same width along the head-tail direction. The wire portion16supports the wire25(described later).

The head portion15continues from the distal end of the linear portion20, and formed into a generally rectangular shape when viewed from the top bulging slightly relative to the wire portion16toward the both left and right side (outside). To be specific, the head portion15include a gimbal23on which a slider22(described later) is mounted, and a gimbal tail portion24which connects the gimbal23and the linear portion20.

The gimbal23is formed into a generally rectangular shape when viewed from the top, and has a width larger than the width of the linear portion20. The gimbal23supports the head-side terminal26(described later), and a slider22(described later) having a magnetic head100(ref:FIG. 2) that is electrically connected with the head-side terminal26is mounted.

The gimbal tail portion24continues to the tail end of the gimbal23, and is formed into a generally triangular shape decreasing its width toward tail-side. The gimbal tail portion24supports the wire25.

The tail portion17continues from the tail end of the bending portion21, and is formed into a generally rectangular shape when viewed from the top having a width that is generally the same with that of the bending portion21. The tail portion17supports the tail-side terminal27(described later).

The conductive layer19integrally includes the wire25extending along the head-tail direction on the metal supporting board18, a head-side terminal26continuing to the head end portion of the wire25, and a tail-side terminal27continuing to the tail end portion of the wire25.

The wire25includes a signal wiring25A that transmits an electric signal between the magnetic head100(ref:FIG. 2) and the read/write board (not shown), and is disposed across the entire suspension board with circuits3in head-tail direction. A plurality (four) of signal wirings25A are disposed in spaced-apart relation in left-right direction.

The wire25further includes a power source wire25B as a second conductive layer. The power source wire25B is electrically connected with a power source-side terminal27B to be described next, and is continued to a power source-side terminal27B at the tail portion17. The power source wire25B is disposed, in proximity to the connection point with the power source-side terminal27B, in parallel in spaced-apart relation on both sides of the signal wiring25A, and at a portion from the connection point with the power source-side terminal27B to the center portion in the head-tail direction of the linear portion20, disposed above the signal wiring25A positioned outside the width direction of the suspension board with circuits3in spaced-apart relation. That is, at the portion from the proximity of the connection point of the power source-side terminal27B to the center portion in the head-tail direction of the linear portion20, the power source wire25B and the signal wiring25A positioned outside the width direction of the suspension board with circuits3are disposed side by side in up-down direction. The power source wires25B are disposed so that they are bent both left and right outer sides to reach the pad portion33(ref:FIG. 3AandFIG. 3B) described later at the center portion in the head-tail direction of the linear portion20.

The head-side terminal26is disposed at the head portion15; to be specific, a plurality (four) of head-side terminals26are disposed at the head-side of the gimbal23, along the head end face of the slider22in spaced-apart relation in left-right direction. The head-side terminals26are head-side terminals to which a magnetic head100(ref:FIG. 2) is electrically connected.

The tail-side terminal27is disposed at the tail end portion of the tail portion17; to be specific, a plurality (six) of tail-side terminals27are disposed in head-tail direction in spaced-apart relation. The tail-side terminal27includes a plurality (four) of external side terminals27A that continue to the signal wiring25A, and are connected to the terminal of the read/write board.

The tail-side terminal27further includes a plurality of (two) power source-side terminals27B that continue to the power source wire25B, and are electrically connected to the piezoelectric element5. The power source-side terminals27B are disposed at both head-tail sides of the external side terminal27A in spaced-apart relation, and are electrically connected to a power source (not shown).

(2-2) Layer Structure of Suspension Board with Circuits

As shown inFIGS. 3 and 4, the suspension board with circuits3includes, at the tail-side half portion, the above-described metal supporting board18, the insulating base layer28provided thereon, the above-described signal wiring25A (conductive layer19) provided on the insulating base layer28, the intermediate insulating layer30provided on the insulating base layer28so as to cover the signal wiring25A, the above-described power source wire25B (conductive layer19) formed on the intermediate insulating layer30, the insulating cover layer29provided on the intermediate insulating layer30so as to cover the power source wire25B (conductive layer19).

At the head-side half portion of the suspension board with circuits3, the power source wire25B (conductive layer19) is not formed on the intermediate insulating layer30but the insulating cover layer29is formed.

The insulating base layer28is formed into a pattern matching to the conductive layer19on the upper face of the metal supporting board18at the head portion15, the wire portion16, and the tail portion17ofFIG. 1. The insulating base layer28is formed from, for example, insulating materials such as synthetic resin including polyimide resin, polyamide-imide resin, acrylic resin, polyethemitrile resin, polyether sulfone resin, polyethylene terephthalate resin, polyethylenenaphthalate resin, and polyvinyl chloride resin. Preferably, the insulating base layer28is formed from polyimide resin. The insulating base layer28has a thickness (maximum thickness) of, for example, 1 μm or more, preferably 2 μm or more, more preferably 3 μm or more, and for example, 25 μm or less, preferably 20 μm or less, more preferably 15 μm or less.

The conductive layer19is formed into the above-described pattern on the upper face of the insulating base layer28and the upper face of the intermediate insulating layer30(described later) at the head portion15, the wire portion16, and the tail portion17ofFIG. 1. The conductive layer19is formed from, for example, conductive materials such as copper, nickel, gold, solder, or alloys thereof. Preferably, the conductive layer19is formed from copper. The conductive layer19has a thickness of, for example, 1 μm or more, preferably 2 μm or more, more preferably 3 μm or more, and for example, 25 μm or less, preferably 20 μm or less, more preferably 15 μm or less. The plurality of wires25each has a width of, for example, 5 μm or more, preferably 8 μm or more, for example, 200 μm or less, preferably 100 μm or less, and the interval between the plurality of wires25when viewed from the top is, for example, 5 μm or more, preferably 8 μm or more, and for example, 1000 μm or less, preferably 100 μm or less. The interval between the wires25disposed in line in up-down direction is, for example, 2 μm or more, preferably 4 μm or more, and for example, 15 μm or less, preferably 10 μm or less. The head-side terminal26and the tail-side terminal27have a width and a length of, for example, 20 μm or more, preferably 30 μm or more, and for example, 1000 μm or less, preferably 800 μm or less. The interval between the plurality of head-side terminals26and the interval between the plurality of tail-side terminals27are, for example, 20 μm or more, preferably 30 μm or more, and for example, 1000 μm or less, preferably 800 μm or less.

The intermediate insulating layer30is formed so as to cover the upper face of the insulating base layer28at the surrounding of the wire25and the side face and the upper face of the wire25formed on the insulating base layer28at the head portion15, the wire portion16, and the tail portion17ofFIG. 1. The intermediate insulating layer30is formed into a pattern that allows, at the head portion15ofFIG. 1, the head-side terminal26to expose, and at the tail portion17, the tail-side terminal27to expose. The intermediate insulating layer30is formed from an insulating material that is the same as the insulating material of the insulating base layer28. The intermediate insulating layer30has a thickness of, for example, 2 μm or more, preferably 4 μm or more, and for example, 12 μm or less, preferably 10 μm or less.

The insulating cover layer29is formed, at a portion from the center portion in the head-tail direction of the linear portion20to the tail portion17ofFIG. 1, so as to cover the upper face of the intermediate insulating layer30surrounding the wire25and the upper face and the side face of the wire25. The insulating cover layer29is formed, at a portion from the center portion in the head-tail direction of the linear portion20to the head portion15ofFIG. 1, on the upper face of the intermediate insulating layer30. The insulating cover layer29is formed into a pattern that allows, at the head portion15ofFIG. 1, the head-side terminal26to expose, and at the tail portion17, allows the tail-side terminal27to expose. The insulating cover layer29is formed from the insulating material that is the same as the insulating material of the insulating base layer28. The insulating cover layer29has a thickness of, for example, 1 μm or more, preferably 2 μm or more, more preferably 3 μm or more, and for example, 10 μm or less, preferably 8 μm or less, more preferably 6 μm or less.

3. Disposal of Suspension Board with Circuits in Assembly

In the suspension board with circuits3of the assembly1, as shown inFIGS. 1 and 2, the lower face of the metal supporting board18is supported by the support plate2. To be specific, the lower face of the wire portion16and the head portion15is supported by the support plate2, and the lower face of the tail portion17protrudes to the tail-side from the support plate2without being supported by the support plate2.

To be specific, the suspension board with circuits3is disposed such that the bending portion21is disposed generally in letter L shape along the left end portion and the head end portion of the tail-plate portion9, and the linear portion20passes through from the center portion in left-right direction of the head end portion of the tail-plate portion9to the center portion in left-right direction of the plate opening12, and thereafter, reaches the center portion in left-right direction of the head-plate portion10. The suspension board with circuits3is disposed such that the head portion15is formed along the head-tail direction of the load beam portion8at the center portion in left-right direction of the load beam portion8.

In the suspension board with circuits3, a piezoelectric element5is mounted. That is, suspension board with circuits3includes the piezoelectric element5.

The piezoelectric element5is attached below the support plate2. To be specific, the plurality of (two) piezoelectric elements5are provided in spaced-apart relation in left-right direction. The two piezoelectric elements5are actuators (piezoelectric element) that are expandable and shrinkable in head-tail direction, and are formed into a generally rectangular shape when viewed from the top extending in head-tail direction. The piezoelectric element5is disposed so as to across the plate opening12in the head-tail direction. To be specific, both end portions in head-tail direction of the two piezoelectric elements5are adhered and fixed to the attachment region13(ref: broken line inFIG. 1) at the head end portion of the tail-plate portion9and at the tail end portion of the head-plate portion10by an adhesive layer31(ref: broken line inFIG. 1).

As shown inFIG. 3, an electrode48is provided at the center portion in the head-tail direction of the upper face of the two piezoelectric elements5, and the electrode48is bonded to a pad portion33to be described next.

To the pair of the piezoelectric elements5, electricity is supplied from the conductive layer19, and shrinkage occurs by controlling the voltage.

4. Connection Arm

InFIG. 6, the insulating cover layer29and the intermediate insulating layer30are omitted to clearly show the structure of the connection arm.

The suspension board with circuits3is provided with, as shown inFIG. 1, a pair of connection arms32.

The pair of connection arms32is provided at both left and right outer sides so as to protrude like an arm from the center portion in the head-tail direction of the linear portion20. To be specific, the left side connection arm32protrudes from the linear portion20to the left side. The right side connection arm32protrudes from the linear portion20to the right side. The right side connection arm32is configured to be axisymmetric with the left side connection arm32relative to the linear portion20. Therefore, in the following, description for the right side connection arm32is omitted and the left side connection arm32is described in detail.

As shown inFIG. 6, the connection arm32includes a pad portion33disposed on the left of the linear portion20in spaced-apart relation, and a joint portion41joining the linear portion20and the pad portion33.

As shown inFIGS. 3 and 5, the pad portion33includes a metal pedestal portion60, an insulating base layer28formed on the metal pedestal portion60, a lower conductive layer61as a first conductive layer formed at the base inner peripheral portion36(described later) of the insulating base layer28, an intermediate insulating layer30formed on the insulating base layer28so as to cover the lower side frame conductor39(described later) of the lower conductive layer61, an upper conductive layer62as a second conductive layer formed on the intermediate insulating layer30and the piezoelectric-side terminal40(described later) of the lower conductive layer61, and an insulating cover layer29formed on the intermediate insulating layer30so as to cover the upper side frame conductor65(described later) of the upper conductive layer62.

As shown inFIG. 6, the metal pedestal portion60is formed into a generally drop shape frame from which a drop is forming toward the right. As shown inFIGS. 5 and 6, at a center portion of the metal pedestal portion60, a pedestal opening34penetrating in the thickness direction and having a generally circular shape when viewed from the top is formed. The right side portion of the metal pedestal portion60protrudes toward the right side. The metal pedestal portion60is formed from a metal material that is the same as that of the metal supporting board18, and its thickness is the same as the thickness of the metal supporting board18. The metal pedestal portion60is disposed at the same position in up-down direction as that of the metal supporting board18.

The insulating base layer28is formed into a generally ring shape when viewed from the top. The external diameter of the insulating base layer28is formed so as to be smaller than the external diameter of the metal pedestal portion60. At a center portion of the insulating base layer28, an above-base opening37penetrating into the thickness direction and having a generally circular shape when viewed from the top is formed. When projected in up-down direction, the above-base opening37is disposed at an inner side of the pedestal opening34. To be specific, the above-base opening37is disposed so as to be concentric with the pedestal opening34, and the internal diameter of the above-base opening37is formed to be smaller than the internal diameter of the pedestal opening34of the metal pedestal portion60.

As shown inFIG. 5, the insulating base layer28of the pad portion33includes a base inner peripheral portion36, which defines the above-base opening37with its inner peripheral end face, and a base outer peripheral portion35defined outside the base inner peripheral portion36. The base inner peripheral portion36is formed to be thinner than the base outer peripheral portion35. To be specific, the base inner peripheral portion36has a thickness of, for example, 0.5 to 5 μm.

At an inner side of the base outer peripheral portion35, below the base inner peripheral portion36, a below-base opening38is formed. The below-base opening38is disposed to be concentric with the above-base opening37, and is formed so that its internal diameter is larger than the internal diameter of the above-base opening37.

The below-base opening38communicates with the pedestal opening34. To be specific, the below-base opening38is formed so as to overlap with the pedestal opening34when projected in up-down direction. That is, the inner periphery of the below-base opening38is formed to be flush with the inner periphery of the pedestal opening34in up-down direction.

The lower conductive layer61is formed into a generally disk shape when viewed from the top, and into a generally inverted hat shape in cross section having a center portion depressing downward relative to the peripheral end portion. The lower conductive layer61includes a lower side frame conductor39formed on the upper face of the base inner peripheral portion36of the insulating base layer28, and a piezoelectric-side terminal40continuing to the inner side of the lower side frame conductor39, and positioned lower than the lower side frame conductor39.

The lower side frame conductor39is formed into a ring shape when viewed from the top, which is smaller than the below-base opening38of the insulating base layer28and the pedestal opening34of the metal pedestal portion60when projected in up-down direction. That is, the lower conductive layer61is disposed in the below-base opening38of the insulating base layer28and the pedestal opening34of the metal pedestal portion60when projected in up-down direction.

The piezoelectric-side terminal40is formed, as shown inFIGS. 5 and 6, when viewed from the top, into a generally circular shape continuing to the inner peripheral portion of the lower side frame conductor39when viewed from the top. The piezoelectric-side terminal40is formed, as shown inFIG. 5, into a step from the inner peripheral portion of the lower side frame conductor39passing in the above-base opening37of the insulating base layer28, further depressing downward. The lower face of the piezoelectric-side terminal40is disposed, at the same position in up-down direction, with the lower face of the base outer peripheral portion35of the insulating base layer28, and the upper face of the metal pedestal portion60. The lower face of the piezoelectric-side terminal40is exposed from the pedestal opening34of the metal pedestal portion60, and the below-base opening38of the insulating base layer28.

In the pad portion33, the intermediate insulating layer30covers the lower side frame conductor39of the lower conductive layer61and the base outer peripheral portion35of the insulating base layer28.

In the pad portion33, the intermediate insulating layer30is formed into a ring shape when viewed from the top, and its outline shape is the same as the outline shape of the insulating base layer28when viewed from the top.

At a center position of the intermediate insulating layer30of the pad portion33, an intermediate opening67penetrating in the thickness direction is formed. The intermediate opening67is formed so as not to overlap with the piezoelectric-side terminal40, and so as to overlap with the lower side frame conductor39of the lower conductive layer61when projected in up-down direction.

The intermediate insulating layer30at the pad portion33includes an intermediate inner peripheral portion63, which defines the intermediate opening67with its inner peripheral end face, and an intermediate outer peripheral portion64defined outside the intermediate inner peripheral portion63. The intermediate inner peripheral portion63is formed to be thinner than the intermediate outer peripheral portion64. To be specific, the intermediate inner peripheral portion63has a thickness of, for example, 1.5 to 5 μm.

The upper conductive layer62is, as shown inFIG. 1, a portion of the power source wire25B, which bends to the left from the proximity of the center portion in the head-tail direction of the linear portion20of the metal supporting board18in the suspension board with circuits3. The upper conductive layer62is a generally disk shape when viewed from the top, and into a generally inverted hat shape in cross section having a center portion depressing downward relative to the peripheral end portion. As shown inFIG. 5, the upper conductive layer62includes an upper side frame conductor65formed on the upper face of the intermediate inner peripheral portion63of the intermediate insulating layer30, and an upper side terminal66continuing to the inner side of the upper side frame conductor65, and positioned lower than the upper side frame conductor65.

The upper side frame conductor65is formed into a generally ring shape when viewed from the top, being larger than the below-base opening38of the insulating base layer28and the pedestal opening34of the metal pedestal portion60when projected in up-down direction. That is, the periphery of the upper conductive layer62is disposed, when projected in up-down direction, outside the below-base opening38of the insulating base layer28and the pedestal opening34of the metal pedestal portion60.

The upper side terminal66is formed, as shown inFIGS. 5 and 6, when viewed from the top, into a generally circular shape continuing to the inner peripheral portion of the upper side frame conductor65when viewed from the top. The upper side terminal66is formed, as shown inFIG. 5, into a step from the inner peripheral portion of the upper side frame conductor65, depressing toward the intermediate opening67of the intermediate insulating layer30and to the upper face of the piezoelectric-side terminal40of the lower conductive layer61. The lower face of the upper side terminal66is in contact with the upper face of the piezoelectric-side terminal40. The upper face of the upper side terminal66is exposed from the cover opening68(described later) of the insulating cover layer29.

In the pad portion33, the insulating cover layer29covers the upper side frame conductor65of the upper conductive layer62and the intermediate outer peripheral portion64of the intermediate insulating layer30.

In the pad portion33, as shown inFIG. 5, the insulating cover layer29has a generally ring shape when viewed from the top, and is formed so that its outline shape is the same shape as the outline shape of the insulating base layer28when viewed from the top.

At a center portion of the insulating cover layer29at the pad portion33, a cover opening68penetrating in the thickness direction is formed. From the cover opening68, the upper side terminal66of the upper conductive layer62is exposed. The cover opening68is formed so as to overlap with the lower side frame conductor39of the lower conductive layer61when projected in up-down direction.

The size of the pad portion33is suitably selected. The metal pedestal portion60has an external diameter (maximum length) of, for example, 60 μm or more, preferably 100 μm or more, and for example, 1500 μm or less, preferably 1300 μm or less. The metal pedestal portion60has an internal diameter (external diameter (maximum length) of the pedestal opening34) of, the same as the internal diameter (external diameter (maximum length) of below-base opening38) of the base outer peripheral portion35of the insulating base layer28.

The distance between the outer periphery of the metal pedestal portion60and the inner periphery of the pedestal opening34is, for example, 10 μm or more, preferably 20 μm or more, and for example, 200 μm or less, preferably 150 μm or less.

The lower side frame conductor39of the lower conductive layer61has an external diameter (maximum length) of, for example, 25 μm or more, preferably 60 μm or more, and for example, 1300 μm or less, preferably 1100 μm or less. The piezoelectric-side terminal40has an external diameter (maximum length) of the same as the external diameter (maximum length) of the above-base opening37.

The intermediate insulating layer30has an external diameter (maximum length) of the same as the external diameter (maximum length) of the insulating base layer28, and the intermediate opening67of the intermediate insulating layer30has an internal diameter (maximum length) that is the same as the internal diameter (external diameter (maximum length) of the above-base opening37) of the base inner peripheral portion36of the insulating base layer28.

The upper side frame conductor65of the upper conductive layer62has an external diameter (maximum length) of, for example, 40 μm or more, preferably 80 μm or more, and for example, 1400 μm or less, preferably 1200 μm or less. The external diameter (maximum length) of the upper side terminal66is the same as the external diameter (maximum length) of the above-base opening37.

The external diameter (maximum length) of the insulating cover layer29is the same as the external diameter (maximum length) of the insulating base layer28, and the cover opening68of the insulating cover layer29has an internal diameter (maximum length) that is the same as the internal diameter (external diameter (maximum length) of the above-base opening37) of the base inner peripheral portion36of the insulating base layer28.

The joint portion41bridges, as shown inFIGS. 5 and 6, the left end portion of the center portion in the head-tail direction of the linear portion20and the right end portion of the pad portion33.

The joint portion41extends in left-right direction, and is formed into a generally rectangular shape having a width smaller than the external diameter of the pad portion33when viewed from the top.

The joint portion41includes an insulating base layer28, an intermediate insulating layer30(omitted inFIG. 6) formed on the insulating base layer28, a power source wire25B formed on the intermediate insulating layer30, and an insulating cover layer29(omitted inFIG. 6) formed on the intermediate insulating layer30so as to cover the power source wire25B.

As shown inFIG. 6, in the joint portion41, the insulating base layer28is formed into a generally rectangular shape when viewed from the top, and formed so that the insulating base layer28of the linear portion20is continuous with the insulating base layer28of the pad portion33.

In the joint portion41, the intermediate insulating layer30is formed on the insulating base layer28so that its outline shape is the same as the outline shape of the insulating base layer28.

The power source wire25B in the joint portion41is formed on the intermediate insulating layer30at the joint portion41so as to extend along left-right direction, and is formed so as to be continuous with the power source wire25B of the linear portion20, and the upper conductive layer62of the pad portion33.

In the joint portion41, the insulating cover layer29is formed on the intermediate insulating layer30so that its outline shape is the same as the outline shape of the insulating base layer28. In the joint portion41, the insulating cover layer29covers the upper face and the side face of the power source wire25B.

In the pad portion33, on the lower face of the piezoelectric-side terminal40, and the upper face of the upper side terminal66of the upper conductive layer62, a plated layer50is formed. Although not shown, in the suspension board with circuits3, the plated layer is formed also on the terminals, to be specific, on the surface of the head-side terminal26(ref:FIG. 1) and the tail-side terminal27(ref:FIG. 1).

The plated layer50is formed from, for example, metal materials such as nickel and gold. Preferably, the plated layer50is formed from gold. The plated layer50has a thickness of, 0.01 μm or more, preferably 0.1 μm or more, and for example, 10 μm or less, preferably 5 μm or less.

5. Production Method of Assembly

Next, description is given below of a method for producing the assembly1.

To produce the assembly1, first, a suspension board with circuits3, a support plate2, and a piezoelectric element5are prepared.

Next, description is given below of a method for preparing (producing) a suspension board with circuits3with reference toFIG. 7AtoFIG. 7EandFIG. 8FtoFIG. 8I.

In this method, as shown inFIG. 7A, first, a metal support layer70is prepared.

The metal support layer70is a substrate for forming a metal supporting board18and a metal pedestal portion60, and the materials and the thickness are the same as those for the above-described metal supporting board18and metal pedestal portion60.

Then, as shown inFIG. 7B, an insulating base layer28is formed on the metal support layer70.

At this time, an above-base opening37is formed on the insulating base layer28.

To form the insulating base layer28, first, for example, varnish of a photosensitive insulating material is applied and dried on the upper face of the metal support layer70, thereby forming a photosensitive base coating.

Then, the photosensitive base coating is exposed to light with an interposing photomask, which is not shown. The photomask includes a pattern of shield portion and transmittance portion, and is disposed on the base coating so that the shield portion faces the portion where the insulating base layer28is not formed (portion where the above-base opening37is formed) and the transmittance portion faces the portion where the insulating base layer28is formed.

Thereafter, the base coating exposed to light is developed, and subjected to thermosetting as necessary, thereby forming the insulating base layer28into the above-described pattern including the above-base opening37.

Then, as shown inFIG. 7C, the lower conductive layer61, and the conductive layer19are formed on the upper face of the insulating base layer28.

To be specific, the lower conductive layer61is formed on the surface of the metal support layer70in the above-base opening37, and the base inner peripheral portion36. At the same time, the conductive layer19is formed into a pattern including a signal wiring25A formed on the insulating base layer28and a head-side terminal26and an external side terminal27A continued therefrom.

The lower conductive layer61, and the signal wiring25A of the conductive layer19are formed by, for example, additive method or subtractive method.

Then, as shown inFIG. 7D, the intermediate insulating layer30is formed in the same manner as the insulating base layer28in the above-described pattern.

Then, as shown inFIG. 7E, the power source wire25B of the conductive layer19is formed on the upper face of the intermediate insulating layer30.

To be specific, as shown inFIG. 1, the conductive layer19is formed into a pattern including the power source wire25B formed on the intermediate insulating layer30, and the power source-side terminal27B and the upper side terminal66continued therefrom.

The power source wire25B of the conductive layer19is formed by, for example, additive method or subtractive method.

Then, as shown inFIG. 8F, the insulating cover layer29is formed into the above-described pattern in the same manner as the insulating base layer28.

Then, as shown inFIG. 8G, the metal support layer70is trimmed, thereby forming the metal supporting board18and metal pedestal portion60having the above-described pattern.

To be specific, the metal support layer70is formed by, for example, etching such as dry etching (e.g., plasma etching) or wet etching (e.g., chemical etching), and for example, drilling, and laser processing, into the shape of the metal supporting board18and the metal pedestal portion60. Preferably, the metal support layer70is trimmed by wet etching.

Then, as shown inFIG. 8H, the insulating base layer28exposed from the pedestal opening34of the metal pedestal portion60is partially removed.

The insulating base layer28is removed, for example, by etching, preferably, and wet etching.

In this manner, a lower portion of the base inner peripheral portion36and the above-base opening37is removed. Then, the below-base opening38is formed.

In this manner, the piezoelectric-side terminal40exposed from the above-base opening37and the below-base opening38is formed.

Thereafter, as shown inFIG. 8I, the plated layer50is formed on the head-side terminal26(ref:FIG. 1), the tail-side terminal27(ref:FIG. 1), the lower face of the piezoelectric-side terminal40, and the upper face of the upper side terminal66by, for example, plating such as electroless plating, and electrolytic plating, preferably by electrolytic plating.

In this manner, the suspension board with circuits3is prepared (produced).

Then, as shown inFIGS. 1 and 2, the prepared suspension board with circuits3, the support plate2, and the piezoelectric element5are assembled.

To be specific, the suspension board with circuits3is disposed on the upper face of the support plate2. That is, as shown inFIG. 1, the suspension board with circuits3is fixed to the support plate2, for example, by welding or by an adhesive so that the linear portion20in the wire portion16crosses the center portion in width direction of the plate opening12, the bending portion21is disposed at the one end portion in the width direction and the head end portion of the tail-plate portion9, and the head portion15is disposed at a center portion in the width direction of the load beam portion8across the head-tail direction of the load beam portion8. Furthermore, the suspension board with circuits3is fixed to the support plate2so that the connection arm32is disposed to the both end portions in width direction of the plate opening12.

Thereafter, as shown inFIG. 3, the piezoelectric element5is fixed to the support plate2, and the electrode48of the piezoelectric element5is supported to the metal pedestal portion60.

To fix the piezoelectric element5to the support plate2, the adhesive layer31is provided in the attachment region13in the actuator plate portion6, and through the adhesive layer31, both end portions in the head-tail direction of the piezoelectric element5is attached to the attachment region13. The piezoelectric elements5are disposed in spaced-apart relation, as shown inFIG. 1, in the plate opening12, at both outer sides in width direction of the linear portion20of the suspension board with circuits3.

To allow the metal pedestal portion60to support the electrode48of the piezoelectric element5, as shown inFIG. 3, an electrically conductive adhesive42is provided at the pedestal opening34and the below-base opening38.

The electrically conductive adhesive42is, for example, an adhesive medium (e.g., electrically conductive pastes such as gold paste and silver paste) that exhibits adhesive effects by heating with a relatively low temperature (e.g., 100 to 200° C.).

The amount of the electrically conductive adhesive42is set to an amount that allows the pedestal opening34and the below-base opening38to be filled, and furthermore, allows the electrically conductive adhesive42to overflow from the pedestal opening34, and allows the electrically conductive adhesive42to cover at least the lower face of the metal pedestal portion60. That is, the amount is set to an amount that is larger than the total volume of the pedestal opening34and the below-base opening38. The amount of the electrically conductive adhesive42is set, for example, to 110 to 1000%, preferably 300 to 800% relative to the total volume of the pedestal opening34and the below-base opening38.

The electrically conductive adhesive42fills the pedestal opening34and the below-base opening38, and is provided at the lower face of the metal pedestal portion60, and the electrode48of the piezoelectric element5makes contact with the electrically conductive adhesive42.

The piezoelectric-side terminal40and the metal pedestal portion60are adhered to the electrode48through the electrically conductive adhesive42.

In this manner, the electrode48is supported by the metal pedestal portion60.

Then, as shown inFIG. 4, the piezoelectric-side terminal40is electrically connected with the electrode48through the plated layer50and the electrically conductive adhesive42. In this manner, the power source wire25B is electrically connected with the electrode48through the upper side terminal66, the piezoelectric-side terminal40, and the electrically conductive adhesive42.

Furthermore, as shown inFIGS. 1 and 2, the slider22on which a magnetic head (not shown) is mounted is mounted on the gimbal23to electrically connect the magnetic head100with the head-side terminal26.

Furthermore, the read/write board (not shown) is electrically connected with the external side terminal27A, and the power source (not shown) is electrically connected with the power source-side terminal27B.

The driving coil (not shown) is attached to the base plate portion7.

Then, in this manner, the assembly1is produced. The assembly1is mounted in a hard disk drive (not shown).

In the hard disk drive, the slider22of the assembly1runs relative to the circumferential direction of the rotating disk-shaped hard disk while slightly floating in spaced-apart relation from the surface of the hard disk, and the magnetic head (not shown) reads and writes information based on the driving of the driving coil while moving in the radial direction of the hard disk.

Furthermore, with expansion and contraction of the piezoelectric element5, positions of the magnetic head relative to the hard disk drive are adjusted precisely.

That is, electricity is supplied from the power source (not shown) through the power source-side terminal27B, the power source wire25B, the upper side terminal66, and the piezoelectric-side terminal40, and the left side piezoelectric element5contracts by the control of the voltage of electricity. Then, the head end portion of the tail-plate portion9and the tail end portion of the head-plate portion10in the left end portion come close to each other while being flexibly supported by the flexible portion11.

At the same time, electricity is supplied from the power source (not shown) through the power source-side terminal27B, the power source wire25B, the upper side terminal66, and the piezoelectric-side terminal40, and the right side piezoelectric element5extends by the control of the voltage of electricity. Then, the head end portion of the tail-plate portion9and the tail end portion of the head-plate portion10in the right end portion go away from each other while being flexibly supported by the flexible portion11.

Then, the head-plate portion10and the load beam portion8swings toward the one side in the width direction with the center portion in width direction of the head end portion of the tail-plate portion9as the supporting point. At the same time, the suspension board with circuits3and the slider22fixed to the load beam portion8swings toward the one side in the width direction.

Meanwhile, the extension on the left side piezoelectric element5and the contraction on the right side piezoelectric element5allow the head-plate portion10and the load beam portion8to swing in the direction opposite to the above-described direction.

6. Operations and Effects

With the suspension board with circuits3, as shown inFIG. 5, the lower conductive layer61is disposed in the pedestal opening34of the metal pedestal portion60when projected in up-down direction, and the periphery of the upper conductive layer62is disposed outside of the pedestal opening34of the metal pedestal portion60when projected in up-down direction.

Therefore, the lower conductive layer61and the upper conductive layer62can be disposed in line in up-down direction, and their strength can be increased.

As a result, damages to the lower conductive layer61and the upper conductive layer62can be suppressed.

That is, even if a force in up-down direction is applied to the lower conductive layer61and the upper conductive layer62in the pad portion33at the time of bonding of the piezoelectric element5to the suspension board with circuits3, the force can be received by the lower conductive layer61and the upper conductive layer62, and therefore damages to the lower conductive layer61and the upper conductive layer62, for example, opening of holes in the lower conductive layer61and the upper conductive layer62can be suppressed.

The lower conductive layer61is disposed in the pedestal opening34of the metal pedestal portion60when projected in up-down direction. That is, in up-down direction, the lower conductive layer61does not overlap with the pedestal opening34of the metal pedestal portion60.

Therefore, flexibility of the suspension board with circuits3can be ensured, and impact to the suspension board with circuits3can be alleviated.

For example, in production of the suspension board with circuits3, when a force is applied in proximity to the pedestal opening34of the metal pedestal portion60, particularly with the insulating base layer28and the intermediate insulating layer30, the impacts can be alleviated.

The periphery of the upper conductive layer62is disposed outside the pedestal opening34of the metal pedestal portion60when projected in up-down direction.

Therefore, strength of the suspension board with circuits3can be ensured.

With the suspension board with circuits3, as shown inFIG. 5, of the lower conductive layer61and the upper conductive layer62, the lower conductive layer61is disposed in the pedestal opening34of the metal pedestal portion60when projected in up-down direction.

Therefore, in the suspension board with circuits3, impacts in the proximity of the pedestal opening34of the metal pedestal portion60can be alleviated.

That is, the insulating base layer28and the intermediate insulating layer30are disposed above the pedestal opening34of the metal pedestal portion60.

Therefore, the insulating base layer28and the intermediate insulating layer30allow impacts in the proximity of the metal pedestal portion60and the pedestal opening34to be alleviated.

7. Modified Examples of Suspension Board with Circuits

Modified examples of the suspension board with circuits are described with reference toFIG. 5, andFIG. 9toFIG. 11. In modified examples, those members that are the same as those in the above-described embodiment are given the same reference numerals, and descriptions thereof are omitted.

(1) Second Embodiment

In the above-described first embodiment, as shown with the solid line inFIG. 5, the insulating cover layer29in the pad portion33covers the upper side frame conductor65of the upper conductive layer62and the intermediate outer peripheral portion64of the intermediate insulating layer30.

In contrast, in the second embodiment, the insulating cover layer29in the pad portion33covers, as shown with the phantom line A inFIG. 5, the entire upper face of the upper side terminal66, that is, the entire upper face of the upper conductive layer62.

To be specific, in the second embodiment, the plated layer50is not formed on the upper face of the upper conductive layer62inFIG. 5, and the insulating cover layer29is formed so as to cover the entire upper face of the upper conductive layer62and the intermediate outer peripheral portion64of the intermediate insulating layer30.

With the suspension board with circuits3in the second embodiment, the insulating cover layer29is formed on the entire upper face of the upper conductive layer62.

Therefore, the upper conductive layer62can be protected with the insulating cover layer29.

In the pad portion33, the lower conductive layer61, the upper conductive layer62, and the insulating cover layer29are disposed in line when projected in up-down direction.

Therefore, strength of the lower conductive layer61and the upper conductive layer62can further be increased.

In the above-described first embodiment, as shown inFIG. 5, the entire lower face of the upper side terminal66in the pad portion33is in contact with the entire upper face of the piezoelectric-side terminal40.

In contrast, in the third embodiment, as shown inFIG. 9, a portion of the lower face of the upper side terminal66in the pad portion33is in contact with the upper face of the piezoelectric-side terminal40.

To be specific, in the third embodiment, in the pad portion33, the intermediate insulating layer30covers the lower side frame conductor39of the lower conductive layer61and the base outer peripheral portion35of the insulating base layer28, and furthermore, covers up to the proximity to the center portion of the piezoelectric-side terminal40of the lower conductive layer61. In other words, the intermediate insulating layer30covers the portion excluding the upper face center portion of the piezoelectric-side terminal40relative to the lower conductive layer61. That is, when projected in up-down direction, the inner peripheral portion (intermediate opening67) of the intermediate insulating layer30is disposed in the projection plane of the piezoelectric-side terminal40of the lower conductive layer61.

The upper conductive layer62is formed on the upper face of the intermediate insulating layer30and the upper face of the center portion of the piezoelectric-side terminal40of the lower conductive layer61.

In this manner, at the upper side terminal66of the upper conductive layer62, the upper side terminal non-contact portion66A, which depresses from the inner peripheral portion of the upper side frame conductor65slightly downward like a step, and then disposed above the piezoelectric-side terminal40of the lower conductive layer61in spaced-apart relation, and the upper side terminal contact portion66B which depresses from the inner peripheral portion (intermediate opening67) of the upper side terminal non-contact portion66A like a step and makes contact with the upper face of the piezoelectric-side terminal40, are formed.

The upper side terminal non-contact portion66A has a generally ring shape when viewed from the top, and forms the outer peripheral portion of the upper side terminal66.

The upper side terminal contact portion66B has a generally circular shape when viewed from the top, and forms the center portion of the upper side terminal66. Then, the lower face of the upper side terminal contact portion66B makes contact with the center portion of the piezoelectric-side terminal40.

With the suspension board with circuits3of the third embodiment, at the portion where the piezoelectric-side terminal40makes contact with the upper side terminal contact portion66B of the upper side terminal66, strength of the piezoelectric-side terminal40and the upper side terminal66can be improved more.

The intermediate insulating layer30is interposed between the piezoelectric-side terminal40and the upper side terminal non-contact portion66A of the upper side terminal66.

Therefore, flexibility of the suspension board with circuits3can be ensured more, and impacts applied to the suspension board with circuits3can be alleviated.

In the third embodiment, the upper side terminal contact portion66B can make contact with the head-side portion of the piezoelectric-side terminal40, and as shown with the phantom line B, and as shown with the phantom line C, can make contact with the tail-side portion of the piezoelectric-side terminal40, and as shown with the phantom line D, can make contact with the lower side frame conductor39of the lower conductive layer61.

In the above-described first embodiment, as shown inFIG. 5, at the pad portion33, the lower conductive layer61is disposed in the pedestal opening34of the metal pedestal portion60, and the periphery of the upper conductive layer62is disposed outside the pedestal opening34of the metal pedestal portion60when projected in up-down direction.

In contrast, in the fourth embodiment, as shown inFIG. 10, at the pad portion33, the periphery of the lower conductive layer75that is disposed below is disposed outside the pedestal opening34of the metal pedestal portion60, and the upper conductive layer80disposed above is disposed in the pedestal opening34of the metal pedestal portion60when projected in up-down direction.

To be specific, in the fourth embodiment, as shown inFIG. 10, the pad portion33includes the lower conductive layer75, and the upper conductive layer80disposed above the lower conductive layer75.

The lower conductive layer75is a portion of the power source wire25B inFIG. 1. The lower conductive layer75includes the lower side frame conductor76formed on the upper face of the base inner peripheral portion36of the insulating base layer28, and the piezoelectric-side terminal77as the terminal continuing to the inner side of the lower side frame conductor76.

The lower side frame conductor76is formed into a generally ring shape when viewed from the top, which is larger than the below-base opening38of the insulating base layer28and the pedestal opening34of the metal pedestal portion60when projected in up-down direction. That is, the periphery of the lower conductive layer75is disposed outside the below-base opening38of the insulating base layer28and the pedestal opening34of the metal pedestal portion60when projected in up-down direction.

The upper conductive layer80includes the upper side frame conductor81formed at the upper face of the intermediate inner peripheral portion63of the intermediate insulating layer30and the upper side terminal82as the terminal continuing to the inner side of the upper side frame conductor81.

The upper side frame conductor81is formed into a generally ring shape when viewed from the top, which is smaller than the below-base opening38of the insulating base layer28and the pedestal opening34of the metal pedestal portion60when projected in up-down direction. That is, the periphery of the upper conductive layer80is disposed in the below-base opening38of the insulating base layer28, and the pedestal opening34of the metal pedestal portion60when projected in up-down direction. In other words, the periphery of the upper conductive layer80does not overlap with the below-base opening38of the insulating base layer28and the pedestal opening34of the metal pedestal portion60when projected in up-down direction.

In the suspension board with circuits3of the fourth embodiment, the periphery of the lower conductive layer75in the proximity of the pedestal opening34of the metal pedestal portion60is disposed outside of the below-base opening38of the insulating base layer28and the pedestal opening34of the metal pedestal portion60when projected in up-down direction.

Therefore, strength of the suspension board with circuits3can be increased at the proximity of the pedestal opening34of the metal pedestal portion60.

In the fourth embodiment, at the center portion in the head-tail direction of the linear portion20to the tail portion17of the suspension board with circuits3, the power source wire25B is not disposed above the signal wiring25A, but disposed at both outer sides of the signal wiring25A disposed outside in width direction of the suspension board with circuits3.

In this manner, in the suspension board with circuits3, the configuration of the signal wiring25A and the power source wire25B can be easily made. In this case, the power source wire25B inFIG. 1is always formed on the insulating base layer28in the suspension board with circuits3. The intermediate insulating layer30is formed only on the pad portion33.

In the above-described fourth embodiment, as shown inFIG. 10, at the pad portion33, the piezoelectric-side terminal77of the lower conductive layer75makes contact with the upper side terminal82of the upper conductive layer80.

In contrast, in the fifth embodiment, as shown inFIG. 11, at the pad portion33, the intermediate insulating layer30is interposed between the piezoelectric-side terminal77of the lower conductive layer75and the upper side terminal82of the upper conductive layer80.

To be specific, in the fifth embodiment, at the pad portion33, the intermediate insulating layer30covers the base outer peripheral portion35of the insulating base layer28, and covers the entire upper face of the lower conductive layer75. That is, in the fifth embodiment, the intermediate opening67is not formed at the intermediate insulating layer30.

Then, the upper conductive layer80is formed on the intermediate insulating layer30. The upper conductive layer80is disposed above the lower conductive layer75in spaced-apart relation.

In the suspension board with circuits3of the fifth embodiment, the upper conductive layer80and the lower conductive layer75are disposed in spaced-apart relation in up-down direction, and the intermediate insulating layer30is interposed therebetween.

Therefore, flexibility of the suspension board with circuits3can be ensured more, and impacts applied to the suspension board with circuits3can be alleviated more.

INDUSTRIAL APPLICABILITY

The wired circuit board of the present invention is used in, for example, a hard disk drive.

DESCRIPTION OF REFERENCE NUMERAL