Method for inspecting electrical connectivity of piezoelectric element and method for manufacturing magnetic head suspension

Abstract

To enable inspection of electrical connectivity between a first electrode terminal area of a first electrode of a piezoelectric element and a first electrode connection area electrically connected to the first electrode terminal area with a conductive adhesive.SOLUTION: The present invention includes: an insulation calculation step for calculating the amount of a first insulating adhesive which is present on an inspection area set so as to include a part of or whole of at least one of a first electrode terminal area and a first electrode connection area, after a piezoelectric element is fixed with the first insulating adhesive at a prescribed setting position; an electrical conductivity calculation step for calculating the amount of a conductive adhesive present on the inspection area, after the first electrode terminal area is electrically connected to the first electrode connection area with the conductive adhesive; and a determination step for determining electrical connectivity between the first electrode and the first electrode connection area based on the difference between the values calculated by the electrical conductivity calculation step and the insulation calculation step.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a method for inspecting the electrical connectivity of a piezoelectric element applied to a magnetic head suspension having a piezoelectric element that slightly moves a gimbal region in a seek direction parallel to a disk surface, and a method for manufacturing the magnetic head suspension. [Background technology]

[0002] As the capacity of magnetic disk devices increases, there is a demand for improved positioning accuracy of the magnetic head slider relative to the target track.To this end, magnetic head suspensions have been proposed that not only coarsely move the magnetic head slider in the seek direction using a main actuator such as a voice coil motor, but also have a piezoelectric element that acts as a sub-actuator, allowing fine movement of the magnetic head slider in the seek direction using the piezoelectric element (see, for example, Patent Documents 1 and 2).

[0003] In detail, the magnetic head suspensions described in Patent Documents 1 and 2 include a support portion that is swung around a swing center directly or indirectly by a main actuator such as a voice coil motor, a load bending portion whose base end is supported by the support portion and has a leaf spring that generates a pressing load that presses the magnetic head slider toward the disk surface, a load beam portion that is supported by the support portion via the load bending portion and transmits the pressing load to the magnetic head slider, a flexure portion including a flexure substrate that supports the magnetic head slider on its lower surface facing the disk surface and has a gimbal region on its upper surface opposite to the disk surface against which a dimple provided on the load beam portion abuts, and wiring fixed to the flexure substrate, and a pair of the piezoelectric elements.

[0004] In the magnetic head suspension, the support portion has a base end support portion having the swing center, a tip end support portion that supports the base end of the load bending portion, and a weak rigidity support portion that connects the tip end support portion and the base end support portion so that the tip end support portion can swing in both directions in the seek direction relative to the base end support portion, based on the longitudinal center line of the suspension, and the weak rigidity support portion has an opening in which the pair of piezoelectric elements are arranged.

[0005] The pair of piezoelectric elements are arranged in the opening of the weak rigidity support part, symmetrical to each other with respect to the longitudinal center line of the suspension and with different directions of expansion and contraction relative to each other, with the base end side fixed to the base end support part with an insulating adhesive and the tip end side fixed to the tip end support part with an insulating adhesive.

[0006] The piezoelectric element has a piezoelectric body and first and second electrodes for applying a voltage to the piezoelectric body, the first and second electrodes being arranged on the side opposite to the disk surface and the side close to the disk surface, respectively.

[0007] The second electrode is electrically connected to the wiring in the wiring body via a conductive adhesive, while the first electrode is electrically connected to a predetermined portion of the support portion (the base end support portion or the tip end support portion) that acts as a ground voltage via a conductive adhesive (hereinafter referred to as the conductive adhesive for the first electrode).

[0008] Here, the conductive adhesive for the first electrode electrically connects the first electrode and the support part (the base end support part or the tip end support part) in a bridge-like manner across the insulating adhesive for fixing the piezoelectric element to the specified part of the support part (the base end support part or the tip end support part).

[0009] Therefore, after the conductive adhesive for the first electrode is applied, it is not possible to confirm which region of the first electrode and which region of the specified part of the support part are electrically connected by the conductive adhesive for the first electrode.

[0010] In other words, if the insulating adhesive covered with the conductive adhesive for the first electrode spreads more than necessary beyond the area where it should originally be applied, even if the conductive adhesive for the first electrode is applied to the area where it should originally be applied, the contact area between the conductive adhesive for the first electrode and a specific portion of the first electrode and / or the support part will be small, and in some cases, a stable electrical connection may not be obtained. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-222075 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-251018 Summary of the Invention [Problem to be solved by the invention]

[0012] The present invention has been made in consideration of the above-mentioned conventional technology, and aims to provide an inspection method applicable to a magnetic head suspension equipped with a piezoelectric element that slightly moves a gimbal region in a seek direction parallel to the disk surface, which can effectively inspect the electrical connectivity between a first electrode in the piezoelectric element and a first electrode connection region to which the first electrode is electrically connected by a first conductive adhesive.

[0013] Furthermore, the present invention aims to provide a manufacturing method for a magnetic head suspension equipped with a piezoelectric element that slightly moves the gimbal region in a seek direction parallel to the disk surface, which manufacturing method can effectively recognize the electrical connectivity between a first electrode in the piezoelectric element and a first electrode connection region to which the first electrode is electrically connected by a first conductive adhesive. [Means for solving the problem]

[0014] In order to achieve the above object, a first aspect of the present invention is a method for inspecting electrical connectivity of a piezoelectric element that is applied when manufacturing a magnetic head suspension, the method comprising: a piezoelectric element that finely moves a gimbal region on which a magnetic head slider is mounted in a seek direction parallel to a disk surface; the piezoelectric element being fixed at a predetermined installation position by a first insulating adhesive; and a predetermined first electrode terminal region of a first electrode on one side in a thickness direction of the piezoelectric element being electrically connected to a predetermined first electrode connection region by a first electrode conductive adhesive that covers the first insulating adhesive in a bridge shape; a conductivity calculation step of calculating the amount of the first electrode conductive adhesive present on the inspection area after electrically connecting the first electrode terminal area to the first electrode connection area with the first electrode conductive adhesive; and a determination step of determining the electrical connectivity between the first electrode and the first electrode connection area based on the difference between the calculated value in the conductivity calculation step and the calculated value in the insulation calculation step.

[0015] For example, the inspection area can be set based on the installation reference point of the piezoelectric element.

[0016] In a first embodiment, the insulation calculation process and the conductivity calculation process are configured to calculate the planar area of ​​the portion of the inspection area that is covered by the corresponding adhesive based on a two-dimensional image of the inspection area captured by a two-dimensional imaging device.

[0017] In this case, the determination process determines the electrical connectivity between the first electrode and the first electrode connection area based on the difference between the planar area of ​​the conductive adhesive for the first electrode calculated by the conductivity calculation process and the planar area of ​​the first insulating adhesive calculated by the insulation calculation process.

[0018] In a second embodiment, the insulation calculation step and the conductivity calculation step are configured to calculate the volume of the corresponding adhesive present on the inspection area based on a three-dimensional image of the inspection area captured by a three-dimensional imaging device.

[0019] In this case, the determination process is configured to determine the electrical connectivity between the first electrode and the first electrode connection area based on the difference between the volume of the conductive adhesive for the first electrode calculated by the conductivity calculation process and the volume of the first insulating adhesive calculated by the insulation calculation process.

[0020] In the first and second aspects, the insulation calculation step and the conductivity calculation step are preferably configured to perform photography by the photography device in a state where ultraviolet light is irradiated onto the inspection area by an ultraviolet irradiation device.

[0021] In order to achieve the above object, a second aspect of the present invention is a method for manufacturing a magnetic head suspension, the method comprising: a piezoelectric element for slightly moving a gimbal region on which a magnetic head slider is mounted in a seek direction parallel to a disk surface; the piezoelectric element being fixed at a predetermined installation position by a first insulating adhesive; and a predetermined first electrode terminal region of a first electrode on one side in a thickness direction of the piezoelectric element being electrically connected to a predetermined first electrode connection region by a first electrode conductive adhesive covering the first insulating adhesive in a bridge shape, the method comprising: a fixing step of fixing the piezoelectric element at the predetermined installation position by the first insulating adhesive; and a first electrode electrical connection step of applying a predetermined amount of the conductive adhesive for the first electrode to electrically connect the first electrode terminal area to the first electrode connection area; a conductivity calculation step of calculating the amount of the conductive adhesive for the first electrode present on the inspection area; and a determination step of determining the electrical connectivity between the first electrode and the first electrode connection area based on the difference between the calculated value in the conductivity calculation step and the calculated value in the insulation calculation step.

[0022] In order to achieve the above object, a third aspect of the present invention is a method for manufacturing a magnetic head suspension, the method comprising: a piezoelectric element for slightly moving a gimbal region on which a magnetic head slider is mounted in a seek direction parallel to a disk surface; the piezoelectric element being fixed at a predetermined installation position by a first insulating adhesive; and a predetermined first electrode terminal region of a first electrode on one side in a thickness direction of the piezoelectric element being electrically connected to a predetermined first electrode connection region by a first electrode conductive adhesive covering the first insulating adhesive in a bridge shape, the method comprising the steps of: fixing the piezoelectric element at the predetermined installation position by the first insulating adhesive; a coating amount calculation step of calculating an amount of the first insulating adhesive present on an inspection area set to include a part or all of at least one of the electrode terminal area and the first electrode connection area, a coating amount calculation step of calculating an amount of the first electrode conductive adhesive to be applied to electrically connect the first electrode terminal area to the first electrode connection area based on the calculation result of the insulation calculation step, and a first electrode electrical connection step of applying the amount of the first electrode conductive adhesive calculated in the coating amount calculation step to electrically connect the first electrode terminal area to the first electrode connection area.

[0023] The manufacturing method according to the third aspect of the present invention can preferably include a conductivity calculation step of calculating the amount of conductive adhesive for the first electrode present on the inspection area, and a determination step of determining the electrical connectivity between the first electrode and the first electrode connection region based on the difference between the calculated value in the conductivity calculation step and the calculated value in the insulation calculation step.

[0024] In the manufacturing methods according to the second and third aspects, the calculation step is configured to calculate the planar area of ​​the portion of the inspection area that is covered by the corresponding adhesive based on a two-dimensional image of the inspection area captured by a two-dimensional imaging device.

[0025] Alternatively, the calculating step may be configured to calculate the volume of the corresponding adhesive present on the inspection area based on a three-dimensional image of the inspection area captured by a three-dimensional imaging device.

[0026] Preferably, the calculation step is configured to perform photography by the photography device in a state where ultraviolet light is irradiated onto the inspection area by an ultraviolet irradiation device.

[0027] The magnetic head suspension includes a support portion that is swung by a main actuator directly or indirectly around a swing center in a seek direction parallel to the disk surface, a load bending portion having a base end supported by the support portion and including a leaf spring that generates a pressing load that presses the gimbal region toward the disk surface, a load beam portion that is supported by the support portion via the load bending portion and transmits the pressing load to the gimbal region, and a flexure portion including a flexure substrate having the gimbal region and a wiring body fixed to the flexure substrate. and a pair of the piezoelectric elements, wherein the support section includes a base end support section having the swing center, a tip end support section supporting the base end of the load bending section, and a weak rigidity support section connecting the tip end support section and the base end support section so that the tip end support section can swing in both directions in the seek direction with respect to the base end support section, with the suspension longitudinal center line as a reference, the weak rigidity support section having openings that allow the pair of piezoelectric elements to be arranged symmetrically on either side of the suspension longitudinal center line, and A support plate is fixed to the lower surface facing the disk surface, the support plate having an access opening that exposes a portion of the lower surface of the pair of piezoelectric elements arranged in the opening toward the disk surface, and supporting the lower surfaces of the pair of piezoelectric elements; the wiring body includes an insulating layer provided on the lower surface of the flexure substrate facing the disk surface, and a conductor layer provided on the lower surface of the insulating layer, the insulating layer having an extension region that extends into the access opening in a plan view, and the conductor layer has signal wiring electrically connected to the magnetic head slider and a voltage conducting layer for supplying a drive voltage to the piezoelectric elements. and a piezoelectric element wiring having a piezoelectric element terminal region located in the extension region, wherein a second electrode on the other side of the piezoelectric element in the thickness direction is electrically connected to the piezoelectric element terminal region via a second electrode conductive adhesive that fills the access opening and the through hole provided in the extension region, the manufacturing methods according to the various configurations of the second and third aspects may include, before the fixing step, applying the second electrode conductive adhesive to the access opening and the through hole and applying a second insulating adhesive for temporary fixing to the support plate,A temporary fixing step is included in which the piezoelectric element is installed so that the second electrode of the piezoelectric element contacts the second electrode conductive adhesive and the peripheral area of ​​the lower surface of the piezoelectric element contacts the second insulating adhesive for temporary fixing.

[0028] In this case, the fixing process is configured to apply the first insulating adhesive to the gaps between the piezoelectric element and each of the base end support portion, the tip end support portion, and the weak rigidity support portion, and the inspection area is set on the first electrode or the support portion.

[0029] the magnetic head suspension comprises a support section that is swung by a main actuator directly or indirectly around a swing center in a seek direction parallel to the disk surface, a load bending section whose base end is supported by the support section and has a leaf spring that generates a pressing load that presses the gimbal area toward the disk surface, a load beam section that is supported by the support section via the load bending section and transmits the pressing load to the gimbal area, a flexure section that includes a flexure substrate having the gimbal area and a wiring body fixed to the flexure substrate, and a pair of the piezoelectric elements. the flexure substrate includes a load beam portion fixing region that is fixed to the load beam portion in an overlapping state, and a flexure tip region that extends from the load beam portion fixing region toward the tip side without being supported by the load beam portion, the flexure tip region having the gimbal region on the upper surface opposite to the disk surface where a dimple provided on the load beam portion abuts and on the lower surface facing the disk surface where the magnetic head slider is mounted, and a gimbal region that extends from the load beam portion fixing region in a symmetrical state with respect to each other with respect to a center line of the suspension in the longitudinal direction a pair of gimbal support pieces that support the gimbal region so that the gimbal region can swing in the roll direction and the seek direction with the dimple as a fulcrum, the gimbal region and the pair of gimbal support pieces are configured to form openings that allow the pair of piezoelectric elements to be arranged symmetrically on either side of a center line in the longitudinal direction of the suspension, the gimbal region is provided with a weak rigidity portion that allows the gimbal region to swing in both directions in the seek direction with the dimple as a fulcrum by expansion and contraction actions of the pair of piezoelectric elements, and the wiring body is the wiring body further comprises an insulating layer fixed to a lower surface of the flexure substrate facing the disk surface, and a conductor layer provided on the lower surface of the insulating layer, the insulating layer having an air gap extending into the opening away from the support state of the flexure substrate, the conductor layer having signal wiring electrically connected to the magnetic head slider and piezoelectric element wiring for supplying a drive voltage to the piezoelectric element, the piezoelectric element wiring having a piezoelectric element terminal area located in the air gap, and the wiring body further having a grounding metal part provided on the lower surface of the air gap insulated from the conductor layer,The aerial region is provided with a first electrode through-hole and a second electrode through-hole that expose the piezoelectric element terminal region and the grounding metal portion to the upper surface side of the insulating layer, respectively, and the region of the piezoelectric element terminal region exposed through the first electrode through-hole forms the first electrode connection region, and when the second electrode on the other side of the piezoelectric element in the thickness direction is electrically connected to the grounding metal portion via a second electrode conductive adhesive filled in the second electrode through-hole, the manufacturing methods according to the various configurations of the second and third aspects further include a second electrode electrical connection step that is performed in parallel with the fixing step, and a piezoelectric element second end fixing step that is performed at any timing after the second electrode electrical connection step.

[0030] The fixing step and the second electrode electrical connection step, which are carried out in parallel, are performed by applying the first insulating adhesive to a portion of the upper surface of the air space where the first longitudinal end of the piezoelectric element is placed and filling the second electrode through-hole with the second electrode conductive adhesive, and then placing the piezoelectric element on the upper surface of the air space. Metal Part The piezoelectric element is configured to have a first end fixed to the upper surface of the aerial region while being electrically connected to the piezoelectric element.

[0031] The piezoelectric element second end fixing step is configured to fix a second longitudinal end of the piezoelectric element to the gimbal region via another second insulating adhesive material.

[0032] In this case, the inspection area is set to an area of ​​the piezoelectric element terminal area that is exposed through the first electrode through hole. [Effects of the Invention]

[0033] According to the inspection method of the present invention, in a magnetic head suspension in which a first electrode of a piezoelectric element fixed to a predetermined installation position by a first insulating adhesive is electrically connected to a predetermined first electrode connection area by a first conductive adhesive, the electrical connectivity between the first electrode and the first electrode connection area can be effectively inspected.

[0034] In addition, according to the manufacturing method of the present invention, a piezoelectric element is fixed to a predetermined installation position using a first insulating adhesive, the amount of the first insulating adhesive present on an inspection area set to include part or all of at least one of the first electrode terminal area of ​​the piezoelectric element and the first electrode connection area to which the first electrode terminal area is electrically connected is calculated, a conductive adhesive for the first electrode is applied to electrically connect the first electrode terminal area to the first electrode connection area, the amount of the conductive adhesive for the first electrode present on the inspection area is calculated, and the electrical connectivity between the first electrode and the first electrode connection area is determined based on the difference between the calculated value of the conductive adhesive for the first electrode and the calculated value of the first insulating adhesive, thereby making it possible to effectively recognize the electrical connectivity between the first electrode and the first electrode connection area in the manufactured magnetic head suspension.

[0035] Furthermore, according to the manufacturing method of the present invention, a piezoelectric element is fixed to a predetermined installation position using a first insulating adhesive, the amount of the first insulating adhesive present on an inspection area set to include part or all of at least one of the first electrode terminal area of ​​the piezoelectric element and the first electrode connection area to which the first electrode terminal area is electrically connected is calculated, the amount of first electrode conductive adhesive to be applied to electrically connect the first electrode terminal area to the first electrode connection area is calculated based on the calculation result of the first insulating adhesive, and the calculated amount of first electrode conductive adhesive is applied to electrically connect the first electrode terminal area to the first electrode connection area, thereby effectively improving the yield rate regarding the electrical connectivity between the first electrode and the first electrode connection area. [Brief explanation of the drawings]

[0036] [Figure 1] FIG. 1 is a plan view of a magnetic head suspension manufactured by a manufacturing method according to an embodiment of the present invention. [Figure 2] FIG. 2 is a bottom view of the magnetic head suspension. [Figure 3]FIG. 3 is a plan view of the main components of the magnetic head suspension in a single unit state. [Figure 4] FIG. 4 is an enlarged view of part IV in FIG. [Figure 5] FIG. 5 is a schematic cross-sectional view taken along line VV in FIG. [Figure 6] 6(a) and 6(b) are a plan view and a bottom view, respectively, of a pre-assembly in which the support portion and the rigid plate of the magnetic head suspension are fixed. [Figure 7] FIG. 7 is an enlarged view of part VII in FIG. [Figure 8] FIG. 8 is an enlarged view of part VIII in FIG. [Figure 9] FIG. 9 is a plan view corresponding to FIG. 4, showing a state in which the conductive adhesive for the first electrode is removed from FIG. [Figure 10] FIG. 10 is a plan view corresponding to FIG. 4, showing a state in which the first insulating adhesive and the conductive adhesive for the first electrode have been removed from FIG. [Figure 11] FIG. 11 is a plan view corresponding to FIG. 9, showing an example in which the first insulating adhesive is applied excessively. [Figure 12] FIG. 12 is a plan view corresponding to FIG. 4, in which the conductive adhesive for the first electrode, the piezoelectric element for the support portion, and the first insulating adhesive are removed from FIG. [Figure 13] FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG. [Figure 14] FIG. 14 is a cross-sectional view corresponding to FIG. 13, showing a state during a process of temporarily fixing the piezoelectric element for the support portion of the magnetic head suspension. [Figure 15] FIG. 15 is a cross-sectional view corresponding to FIG. 13, showing the state after the temporary fixing step is completed. [Figure 16] FIG. 16 is a plan view corresponding to FIG. 8, with the load beam portion removed. [Figure 17]FIG. 17 is a cross-sectional view taken along line XVII-XVII in FIG. [Figure 18] FIG. 18 is a plan view corresponding to FIG. 16, in which the piezoelectric element for the flexure portion is omitted. [Figure 19] FIG. 19 is a cross-sectional view taken along line XIX-XIX in FIG. [Figure 20] FIG. 20 is a cross-sectional view corresponding to FIG. 19, showing a state midway through a fixing step and a second electrode electrical connection step which are carried out in parallel when fixing the flexure portion piezoelectric element. [Figure 21] FIG. 21 is a plan view corresponding to FIGS. 16 and 18, showing a state after the fixing step and the second electrode electrical connection step have been completed. [Figure 22] FIG. 22 is a cross-sectional view taken along line XXII-XXII in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0037] Hereinafter, an embodiment of a method for manufacturing a magnetic head suspension according to the present invention will be described with reference to the accompanying drawings. 1 and 2 respectively show a plan view (viewed from the side opposite to the disk surface) and a bottom view (viewed from the disk surface) of a magnetic head suspension 1 manufactured by the manufacturing method according to the present embodiment. In addition, the small circles in Figures 1 and 2 indicate welding points. FIG. 3 shows a plan view (viewed from the side opposite to the disk surface) of the main components of the magnetic head suspension in a single unit state.

[0038] As shown in FIGS. 1 to 3, the magnetic head suspension 1 comprises: a support portion 10 that is swung directly or indirectly around a swing center C in a seek direction parallel to the disk surface by a main actuator (not shown) such as a voice coil motor; a load bending portion 40 including a leaf spring 41 whose base end is connected to the support portion 10 so as to generate a load for pressing the magnetic head slider 90 toward the disk surface; a load beam portion 50 that is supported by the support portion 10 via the leaf spring 41 and transmits the load to the magnetic head slider 90; and a flexure portion 60 that is supported by the load beam portion 50 and supports the magnetic head slider 90 in a gimbal region 610 provided on the tip side.

[0039] The support portion 10 is a member that supports the load beam portion 50 via the leaf spring 41 while being directly or indirectly connected to the main actuator, and has relatively high rigidity. The support portion 10 is preferably formed of, for example, a stainless steel plate having a thickness of 0.1 mm to 0.8 mm.

[0040] In the magnetic head suspension 1, as shown in Figures 1 to 3, the support portion 10 is a base plate having a boss portion that is joined by crimping to the tip of a carriage arm (not shown) that is connected to the main actuator. Naturally, it is also possible to employ as the support part 10 an arm whose base end is connected to the swing center C of the main actuator.

[0041] The support portion 10 has a base end support portion 11 having the swing center C, a tip end support portion 13 that supports the base end side of the load bending portion 40, and a weak rigidity support portion 15 that connects the tip end support portion 13 and the base end support portion 11.

[0042] The weakly rigid support portion 15 connects the tip end support portion 13 to the base end support portion 11 so that the tip end support portion 13 can swing in both directions in the seek direction relative to the suspension longitudinal center line (hereinafter referred to as the longitudinal center line L).

[0043] The magnetic head suspension 1 is configured so that the gimbal area 610 (the magnetic head slider 90) can be coarsely moved in the seek direction by the main actuator, and also so that the gimbal area 610 (the magnetic head slider 90) can be finely moved in the seek direction by the sub-actuator.

[0044] Specifically, the magnetic head suspension 1 further includes a pair of supporting portion piezoelectric elements 100 that act as the sub-actuators.

[0045] The pair of support portion piezoelectric elements 100 are arranged so as to swing the tip end side support portion 13 relative to the base end side support portion 11 in both directions in the seek direction with the longitudinal center line L as the reference in response to application of a voltage.

[0046] In detail, as shown in FIG. 3, the weakly rigid support portion 15 is arranged on the longitudinal center line L and has an opening 19 that allows the pair of support portion piezoelectric elements 100 to be arranged symmetrically on either side of the longitudinal center line L.

[0047] FIG. 4 shows an enlarged view of part IV in FIG. FIG. 5 shows a schematic cross-sectional view taken along line VV in FIG.

[0048] As shown in Figures 3 and 5, the magnetic head suspension 1 further has a support plate 20 that supports the lower surfaces of the pair of support portion piezoelectric elements 100 and has an access opening 29 that exposes a portion of the lower surfaces (surfaces facing the disk surface) of the pair of support portion piezoelectric elements 100 to the disk surface side.

[0049] In the magnetic head suspension 1, as shown in Figures 2 and 3, the load beam portion 50 and the load bending portion 40 are formed by a single rigid plate 30, and the support plate 20 is also formed integrally with the rigid plate 30.

[0050] Figures 6(a) and (b) respectively show a plan view (viewed from the side opposite the disk surface) and a bottom view (viewed from the disk surface side) of the pre-assembly to which the support part 10 and the rigid plate 30 are fixed.

[0051] The support plate 20 is fixed to the lower surface of the support portion 10 (the surface facing the disk surface).

[0052] In detail, as shown in Figures 6(a) and (b), the support plate 20 has a base end plate portion 21 including a base end fixing region 21a fixed in an overlapping state to the underside of the base end support portion 11 and a base end extending region 21b extending from the base end fixing region 21a into the opening 19, and a tip end plate portion 23 including a tip end fixing region 23a fixed in an overlapping state to the underside of the tip end support portion 13 and a tip end extending region 23b extending from the tip end fixing region 23a into the opening 19, and the access opening 29 is provided between the base end extending region 21b and the tip end extending region 23b in the longitudinal direction of the magnetic head suspension 1.

[0053] In the magnetic head suspension 1, the support plate 20 further has an intermediate plate portion 25 including an intermediate fixing region 25a fixed in an overlapping state to the underside of the weakly rigid support portion 15 and an intermediate extension region 25b extending from the intermediate fixing region 25a into the opening 19.

[0054] The support plate 20 further has a base end side piece 26 extending from the base end side plate portion 21 toward the tip end, outward in the suspension width direction from the installation position of the piezoelectric element 100 for the support portion, and a tip end side piece 27 extending from the tip end side plate portion 23 toward the base end, outward in the suspension width direction from the installation position of the piezoelectric element 100 for the support portion, and the base end side piece 26 and the tip end side piece 27 are butted together via a slit.

[0055] The load beam portion 50 is a member for transmitting the load generated by the leaf spring 41 to the gimbal region 610, and therefore is required to have a predetermined rigidity.

[0056] As shown in Figures 1 to 3, the load beam portion 50 has a flat main body portion 51 facing the disk surface, and a pair of left and right flange portions 52 extending from both sides of the main body portion 51 in the suspension width direction in the direction opposite to the disk surface, and the flange portions 52 improve rigidity. The load beam portion 50 is preferably formed from a stainless steel plate having a thickness of 0.02 mm to 0.1 mm, for example.

[0057] As shown in FIGS. 1 and 3, the load beam portion 50 further has a protrusion called a dimple 53 located on the tip end side of the main body portion 51 and on the center line L of the suspension in the longitudinal direction.

[0058] The dimple 53 protrudes, for example, by about 0.05 mm to 0.1 mm in the direction approaching the disk surface. The dimple 53 comes into contact with the upper surface (the back surface opposite to the support surface that supports the magnetic head slider 90) of a gimbal region (head mounting region) 610 of the flexure portion 60, and transmits the load to the gimbal region 610 via the dimple 53.

[0059] 1 to 3, the load beam portion 50 further includes a lift tab 54 extending integrally from the tip of the main body portion 51 toward the tip end of the suspension in the longitudinal direction. The lift tab 54 is a member that engages with a ramp provided in the magnetic disk drive to separate the magnetic head slider 90 from the disk surface in the z direction perpendicular to the disk surface when the magnetic head suspension 1 is swung by the main actuator so that the magnetic head slider 90 is positioned radially outward from the disk surface.

[0060] In the magnetic head suspension 1, as shown in Figures 1 to 3, both sides of the main body portion 51 of the load beam portion 50 in the suspension width direction are inclined in an approximately linear manner so as to approach the suspension longitudinal center line CL as they move from the base end side to the tip end side in the suspension longitudinal direction.

[0061] According to this configuration, the moment of inertia around the center line CL at the tip end side of the load beam portion 50 can be reduced, and the resonance frequencies of the torsion mode and the sway mode can be increased.

[0062] In the magnetic head suspension 1, the load beam portion 50 is bent at its tip end in a direction away from the disk surface around a load beam bending line (not shown) extending in the suspension width direction.

[0063] By adjusting the bending angle at the bending line of the load beam portion, it is possible to reduce the positional deviation (gain) of the magnetic head slider 90 during vibration in torsional mode (especially the primary torsional mode, which has the lowest resonant frequency among torsional mode vibrations).

[0064] The leaf spring 41 has a base end connected to the tip side of the support portion 10 and a tip end connected to the base end of the load beam portion 50 with the plate surface facing the disk surface. The leaf spring 41 is bent around a load bending line (not shown) so that the tip side of the load beam portion 50 approaches the disk surface, and the magnetic head suspension 1 is incorporated into the hard disk drive in a state in which the leaf spring 41 is bent back a predetermined amount around the load bending line and retains elasticity.

[0065] More specifically, when the hard disk drive is in operation and the disk surface rotates, the magnetic head slider 90 receives air pressure accompanying the rotation of the disk surface and floats in a direction away from the disk surface, and in response to this floating movement of the magnetic head slider 90, the leaf spring 41 is further elastically deformed in the bending back direction, increasing its retained elasticity.

[0066] That is, the elastic deformation of the leaf spring 41 when the magnetic head suspension 1 is incorporated into the hard disk drive and the elastic deformation of the leaf spring 41 due to the floating movement of the magnetic head slider 90 accompanying the rotation of the disk surface cause the retained elasticity of the leaf spring 41 to act as a pressing load that presses the magnetic head slider 90 against the disk surface.

[0067] The plate spring 41 is formed of, for example, a stainless steel plate having a thickness of 0.02 mm to 0.1 mm.

[0068] As described above, in the magnetic head suspension 1, the leaf spring 41 is integrally formed with the rigid plate 30 together with the load beam portion 50 and the support plate 20.

[0069] The flexure portion 60 is fixed to the load beam portion 30 in a state in which the magnetic head slider 90 is supported at the gimbal region 610 .

[0070] More specifically, the flexure portion 60 has a flexure substrate 61 including the gimbal region 610 and a wiring body 70 fixed to the flexure substrate 61 .

[0071] FIG. 7 shows an enlarged view of part VII in FIG. In order to facilitate understanding of the flexure substrate 61, the wiring body 70 is omitted in FIG. 7, and the magnetic head slider 90 is indicated by a two-dot chain line.

[0072] As shown in Figures 2, 3 and 7, the flexure substrate 61 has a load beam portion fixing region 62 that is fixed by welding in an overlapping state to the underside (disk-facing surface) of the main body portion 51 of the load beam portion 50, and a flexure tip region 63 that extends from the load beam portion fixing region 62 toward the tip side.

[0073] As shown in FIG. 2, the load beam portion fixing region 62 is fixed to the main body portion 51 by spot welding 95 at welding points arranged symmetrically on the left and right sides with respect to the center line L of the suspension in the longitudinal direction.

[0074] In the magnetic head suspension 1, as shown in FIG. 2, the load beam portion fixing region 62 is welded to the main body 51 of the load beam portion 50 at a pair of tip side welding points 95a arranged symmetrically on the tip side with respect to the suspension longitudinal center line L, a pair of base side welding points 95c arranged symmetrically on the base side with respect to the suspension longitudinal center line L, and an intermediate welding point 95b arranged on the suspension longitudinal center line L between the tip side welding points 95a and the base side welding points 95c in the suspension longitudinal direction.

[0075] The flexure substrate 61 further has a support portion fixing region 64 that extends from the load beam portion fixing region 62 toward the base end and is fixed to the lower surface of the support portion 10 .

[0076] The support fixing region 64 is fixed to the underside of the support 10 by spot welding at a plurality of welding points.

[0077] The flexure tip region 63 has the gimbal region 610 and a pair of gimbal support pieces 620 that extend symmetrically from the load beam portion fixing region 62 toward the suspension longitudinal tip side with respect to the suspension longitudinal center line L and support the gimbal region 610.

[0078] The gimbal region 610 abuts the dimples provided on the load beam portion 50 on its upper surface (surface opposite to the disk surface) and supports the magnetic head slider 90 on its lower surface (surface facing the disk surface).

[0079] The gimbal support piece 620 supports the gimbal region 610 so that the gimbal region 610 can swing in the roll direction and the seek direction with the dimple 53 as a fulcrum.

[0080] FIG. 8 shows an enlarged view of part VIII in FIG. As shown in FIGS. 1 and 8, the magnetic head suspension 1 further includes a pair of flexure piezoelectric elements 150 that function as the sub-actuators.

[0081] More specifically, as shown in FIG. 7, the gimbal region 610 and the pair of gimbal support pieces 620 are configured to form an opening 69 that allows the pair of flexure portion piezoelectric elements 150 to be arranged symmetrically on either side of the suspension longitudinal center line L.

[0082] In the magnetic head suspension 1, as shown in FIG. 7, the gimbal region 610 has a wide portion 612 located at the tip end of the suspension in the longitudinal direction, and a narrow portion 614 extending from the wide portion 612 to the base end of the suspension in the longitudinal direction, with the tip end connected to the wide portion 612.

[0083] As shown in FIG. 7 , the gimbal support piece 620 has a tip-side extending portion 621 extending from the load beam portion fixing region 62 toward the tip side in the longitudinal direction of the suspension, a tip-side width-direction extending portion 622 extending from the tip-side width-direction extending portion 621 inward in the width direction of the suspension, a base-side extending portion 623 extending from the tip-side width-direction extending portion 622 toward the base side in the longitudinal direction of the suspension, and a base-side width-direction extending portion 624 extending from the base-side extending portion 623 inward in the width direction of the suspension and connected to the base end side of the narrow width portion 614.

[0084] In a plan view, the space surrounded by the wide portion 612, the narrow portion 614, the base end widthwise extending portion 624 and the base end direction extending portion 623 forms the opening 69 that allows the flexure portion piezoelectric element 150 to be installed.

[0085] Furthermore, in the magnetic head suspension 1, the gimbal region 610 is provided with a weak rigidity portion 615 that enables the gimbal region 610 to swing in both directions in the seek direction with the dimple 53 as a fulcrum due to the expansion and contraction action of the pair of flexure portion piezoelectric elements 150. As shown in FIG. 7, a notch provided in the narrow width portion 614 and opening outward in the suspension width direction forms the weak rigidity portion 615 .

[0086] As shown in FIG. 7, the flexure substrate 61 has a pair of tip support pieces 630 that extend from the tip extension portions 621 of the pair of gimbal support pieces 620 toward the tip side in the longitudinal direction of the suspension and are connected to each other on the tip side in the longitudinal direction of the suspension from the gimbal region 610.

[0087] The pair of tip support pieces 630 are fixed to the load beam portion 50 by spot welding at welding points 96 (see FIG. 7) on the center line L of the suspension in the longitudinal direction.

[0088] The flexure substrate 61 has lower rigidity than the load beam portion 50 so that the gimbal region 610 can swing in the roll and pitch directions. The flexure substrate 61 is suitably formed of a metal material such as stainless steel with a thickness of about 0.01 mm to 0.025 mm.

[0089] As shown in Figure 3, the wiring body 70 has an insulating layer 71 made of polyimide or the like fixed to the lower surface of the flexure substrate 61 facing the disk surface, and a conductor layer 73 made of Cu or the like provided on the lower surface of the insulating layer 71.

[0090] The conductor layer 73 has signal wiring 730 electrically connected to the magnetic head slider 90 and piezoelectric element wiring for supplying a drive voltage to the piezoelectric elements 100 and 150 .

[0091] As described above, the magnetic head suspension 1 has the pair of support portion piezoelectric elements 100 and the pair of flexure portion piezoelectric elements 150 as the sub-actuators. Therefore, as shown in FIG. 3, the conductor layer 73 has, as the piezoelectric element wiring, piezoelectric element wirings 734 for the support portion and piezoelectric element wirings 736 for the flexure portion.

[0092] A method for manufacturing the magnetic head suspension 1 will now be described. As described above, the magnetic head suspension 1 has the pair of support portion piezoelectric elements 100 and the pair of flexure portion piezoelectric elements 150, and therefore the manufacturing method includes a process of electrically connecting the support portion piezoelectric elements 100 to the support portion piezoelectric element wiring 734 while fixing them in a predetermined position (hereinafter referred to as the support portion piezoelectric element fixing process), and a process of electrically connecting the flexure portion piezoelectric element 150 to the flexure portion piezoelectric element wiring 736 while fixing them in a predetermined position (hereinafter referred to as the flexure portion piezoelectric element fixing process).

[0093] First, the process of fixing the piezoelectric element for the support portion will be described. As shown in FIG. 5, the piezoelectric element 100 for the support portion has a piezoelectric body 105 and first and second electrodes (not shown) for applying a voltage to the piezoelectric body 105, the first and second electrodes being arranged on one side and the other side of the piezoelectric body 105 in the thickness direction, respectively.

[0094] As shown in Figures 4 and 5, when the piezoelectric element 100 for the support portion is fixed to a predetermined installation position by a first insulating adhesive 110, a predetermined first electrode terminal area of ​​the first electrode is electrically connected to a predetermined first electrode connection area by a conductive adhesive for the first electrode 120, and the second electrode is electrically connected to a predetermined second electrode connection area by a conductive adhesive for the second electrode 125.

[0095] As shown in Figures 4 to 6, in the magnetic head suspension 1, the support portion piezoelectric element 100 is fixed to the upper surface (the surface opposite the magnetic disk) of the base end extension region 21b, the tip end extension region 23b and the intermediate extension region 25b by a first insulating adhesive 110, and the first electrode located on the upper surface side opposite the magnetic disk is electrically connected to the upper surface (the surface opposite the magnetic disk) of the support portion 10 by a first electrode conductive adhesive 120, and the second electrode located on the lower surface side closest to the magnetic disk is electrically connected to the support portion piezoelectric element wiring 734 by a second electrode conductive adhesive 125.

[0096] That is, in the magnetic head suspension 1, the first electrode of the support portion piezoelectric element 100 is electrically connected to the upper surface of the support portion 10 and set to ground voltage, and then a predetermined voltage is applied to the second electrode via the support portion piezoelectric element wiring 734, thereby causing the support portion piezoelectric element 100 to expand and contract.

[0097] The adhesives 110 and 120 are each discharged in a preset amount by a dispensing device such as a dispenser.

[0098] FIG. 9 is a plan view corresponding to FIG. 4, showing a state in which the conductive adhesive 120 for the first electrode has been removed from FIG. 10 is a plan view corresponding to FIG. 4, showing a state in which the first insulating adhesive 110 and the first electrode conductive adhesive 120 have been removed from FIG. 9 and 10, the outer shape of the conductive adhesive 120 for the first electrode in plan view is indicated by a two-dot chain line.

[0099] In this embodiment, as shown in FIG. 10, a predetermined area set in advance on the upper surface of the support portion 10 is used as the first electrode connection area.

[0100] In this manner, in a structure in which the first electrode connection region is provided on the upper surface of the support portion 10, the following problems may arise regarding the electrical connection between a predetermined first electrode terminal region in the first electrode of the support portion piezoelectric element 100 and the first electrode connection region.

[0101] That is, as shown in Figures 4 and 5, the first electrode conductive adhesive 120, which electrically connects a predetermined first electrode terminal area in the first electrode of the support portion piezoelectric element 100 and the first electrode connection area (a predetermined area on the upper surface of the support portion 10), is applied so as to straddle the predetermined first electrode terminal area in the first electrode of the support portion piezoelectric element 100 and the first electrode connection area provided on the upper surface of the support portion 10, while covering in a bridge shape the first insulating adhesive 110 for fixing the support portion piezoelectric element 100 in a predetermined position.

[0102] Specifically, the first insulating adhesive 110 is filled in gaps 112 (see Figure 10) between the piezoelectric element 100 and each of the base end support portion 11, the tip end support portion 13, and the weak rigidity support portion 15.

[0103] Here, the first insulating adhesive 110 filled in the gap 112 may overflow onto the upper surface of the support portion piezoelectric element 100 and the upper surface of the support portion 10 due to some cause.

[0104] In the magnetic head suspension 1, as shown in FIG. 9, the first insulating adhesive 110 filled in the gap 112 overflows onto the upper surface of the support portion piezoelectric element 100 and the upper surface of the support portion 10, covering part of the first electrode terminal area and part of the first electrode connection area (the filled-in area in FIG. 9).

[0105] However, after the conductive adhesive 120 for the first electrode is applied, it is not possible to distinguish whether the first insulating adhesive 110 covers part or all of the first electrode terminal area and / or the first electrode connection area, as shown in FIG. 4.

[0106] In other words, after the conductive adhesive 120 for the first electrode is applied, even if it appears that the first electrode terminal area and the first electrode connection area are properly electrically connected by the conductive adhesive 120 for the first electrode, there is a risk that in reality, proper electrical connection is not achieved by the first insulating adhesive 110.

[0107] In the example shown in FIG. 9, only the lattice-shaped hatched area in the first electrode terminal area and only the lattice-shaped hatched area in the first electrode connection area are electrically connected by the conductive adhesive 120 for the first electrode.

[0108] FIG. 11 is a plan view corresponding to FIG. 9, showing an example in which the first insulating adhesive 110 is applied excessively. In the example shown in FIG. 11, most of the first electrode terminal region and most of the first electrode connecting region (the solid-colored portions in FIG. 11) are covered with the first insulating adhesive material.

[0109] Therefore, even if the conductive adhesive 120 for the first electrode is applied properly, it will be difficult to obtain proper electrical connection between the first electrode terminal area and the first electrode connection area (only the grid-shaped hatched area in Figure 11 will be electrically connected).

[0110] In consideration of such problems, the process of fixing the piezoelectric element for the support portion is as follows: a fixing step of fixing the support portion piezoelectric element 100 to a predetermined installation position with the first insulating adhesive material 110; an insulation calculation step of calculating the amount of the first insulating adhesive 110 present on an inspection area 200 set so as to include a part or all of at least one of the first electrode terminal area and the first electrode connection area; a first electrode electrical connection step of electrically connecting the first electrode terminal region to the first electrode connection region by the first electrode conductive adhesive material 120; a conductivity calculation step of calculating the amount of the conductive adhesive 120 for the first electrode present on the inspection area 200; The method further includes a determination step of determining electrical connectivity between the first electrode terminal region and the first electrode connection region based on the difference between the calculated value in the conductivity calculation step and the calculated value in the insulation calculation step.

[0111] As shown in FIG. 4 and other figures, in this embodiment, the inspection area 200 is set in a predetermined area on the upper surface (first electrode) of the support portion piezoelectric element 100 so as to include a part of the first electrode terminal area.

[0112] Alternatively, or in addition, the inspection area 200 can be set in a predetermined area on the upper surface of the support 10 so as to include a part or the whole of the first electrode connection area.

[0113] The insulation calculation process, the conductivity calculation process, and the judgment process are performed using an imaging device (not shown) capable of photographing the inspection area 200, and a control device (not shown) that receives images of the inspection area 200 from the imaging device.

[0114] When the imaging device is a two-dimensional imaging device, the control device is configured to, in the insulation calculation step, calculate the planar area of ​​the portion of the inspection area 200 that is covered by the first insulating adhesive 110 (the filled-in portion on the left in Figure 9) based on a two-dimensional image of the inspection area 200 captured by the two-dimensional imaging device, and in the conductivity calculation step, calculate the planar area of ​​the portion of the inspection area 200 that is covered by the first electrode conductive adhesive 120 (the sum of the filled-in portion on the left and the lattice-shaped hatched portion on the left in Figure 9) based on the two-dimensional image of the inspection area 200 captured by the two-dimensional imaging device, and in the determination step, determine the electrical connectivity between the first electrode terminal area and the first electrode connection area based on the difference (the lattice-shaped hatched portion on the left in Figure 9) between the planar area of ​​the first electrode conductive adhesive 120 calculated in the conductivity calculation step and the planar area of ​​the first insulating adhesive 110 calculated in the insulation calculation step.

[0115] Alternatively, if the imaging device is a three-dimensional imaging device, the control device is configured to, in the insulation calculation step, calculate the volume of the first insulating adhesive 110 present on the inspection area 200 based on a three-dimensional image of the inspection area 200 captured by the three-dimensional imaging device, and in the conductivity calculation step, calculate the volume of the first electrode conductive adhesive 120 present on the inspection area 200 based on the three-dimensional image of the inspection area 200 captured by the three-dimensional imaging device, and in the determination step, determine the electrical connectivity between the first electrode terminal area and the first electrode connection area based on the difference between the volume of the first electrode conductive adhesive 120 calculated in the conductivity calculation step and the volume of the first insulating adhesive 110 calculated in the insulation calculation step.

[0116] Preferably, the insulation calculation step and the conductivity calculation step are configured to perform photography by the photography device in a state where ultraviolet light is irradiated onto the inspection area 200 by an ultraviolet light irradiation device (not shown).

[0117] According to this configuration, the boundaries of the first insulating adhesive 110 and the boundaries of the conductive adhesive 120 for the first electrode within the inspection area 200 can be detected more accurately, and the amount of each adhesive can be calculated accurately.

[0118] The inspection area 200 can be set, for example, based on an installation reference point used when the support portion piezoelectric element 100 is installed at a predetermined position.

[0119] According to the manufacturing method of this embodiment, which includes the insulation calculation process, the conductivity calculation process, and the judgment process, it is possible to recognize the electrical connectivity between the first electrode terminal region and the first electrode connection region in the manufactured magnetic head suspension 1.

[0120] As mentioned above, the manufacturing method of this embodiment is useful in that it can prevent manufactured magnetic head suspensions 1 from being shipped with poor electrical connections between the first electrode terminal region and the first electrode connection region, but it is also possible to modify the manufacturing method to include the fixing process, the insulation calculation process, the application amount calculation process, and the first electrode electrical connection process.

[0121] The application amount calculation process is configured to calculate the amount of the first electrode conductive adhesive 120 to be applied to electrically connect the first electrode terminal area to the first electrode connection area based on the calculation results of the insulation calculation process.

[0122] For example, the control device may be pre-stored with data showing the relationship between the amount of first insulating adhesive 110 present on the inspection area 200 and the appropriate amount of conductive adhesive 120 for the first electrode to be applied, and the calculation results of the insulation calculation process may be applied to the data to calculate the appropriate application amount of conductive adhesive 120 for the first electrode.

[0123] The data is set based on experiments, etc., and is set so that the greater the amount of first insulating adhesive 110 present on the inspection area 200, the greater the appropriate application amount of conductive adhesive 120 for the first electrode.

[0124] In the modified example, the first electrode electrical connection process applies the conductive adhesive 120 for the first electrode in an amount calculated by the application amount calculation process, thereby electrically connecting the first electrode terminal area to the first electrode connection area.

[0125] That is, in the first electrode electrical connection process, the control device operates the discharge device for the conductive adhesive 120 for the first electrode so that the conductive adhesive 120 for the first electrode is discharged in the amount calculated in the application amount calculation process.

[0126] According to the modified example of such a configuration, for example, when the first insulating adhesive 110 is not present on the inspection area 200 or when the amount of the first insulating adhesive 110 on the inspection area 200 is small, the amount of the conductive adhesive 120 for the first electrode to be applied can be set to a small initial setting amount, while when a large amount of the first insulating adhesive 110 is present on the inspection area 200, the amount of the conductive adhesive 120 for the first electrode to be applied can be increased from the initial setting amount.

[0127] Therefore, it is possible to effectively prevent poor electrical connection between the first electrode terminal region and the first electrode connection region while properly controlling the amount of the first conductive adhesive 120 to be applied.

[0128] Preferably, the manufacturing method according to the modified example can include the conductivity calculation step and the determination step after the electrical connection step.

[0129] As described above, in the magnetic head suspension 1, the second electrode (the electrode located on the underside close to the magnetic disk) of the support portion piezoelectric element 100 is electrically connected to the support portion piezoelectric element wiring 734 in the wiring body 70 of the flexure portion 60 by the second electrode conductive adhesive 125.

[0130] FIG. 12 shows a plan view of the state in which the first electrode conductive adhesive 120, the support portion piezoelectric element 100, and the first insulating adhesive 110 have been removed from FIG. Furthermore, FIG. 13 shows a cross-sectional view taken along line XIII-XIII in FIG.

[0131] As shown in FIGS. 3, 12, and 13, the insulating layer 71 of the wiring body 70 has an extension region 712 that extends into the access opening 29 in a plan view. The extension region 712 is provided with a through-hole 712a that penetrates from the upper surface to the lower surface.

[0132] The support piezoelectric element wiring 734 has a support piezoelectric element terminal region 735 accessible from the upper surface side of the extension region 712 via the through hole 712a.

[0133] In this case, the support portion piezoelectric element fixing process includes, before the fixing step, filling the access opening 29 and the through hole 712a of the extension region 712 with a second electrode conductive adhesive 125 so that the upper end position is located above the upper surface of the support plate 20, and applying a second insulating adhesive 111 for temporary fixing to the upper surface (the surface opposite to the disk surface) of the extension region (in this embodiment, the base end side extension region 21b, the tip end side extension region 23b, and the intermediate extension region 25b) of the support plate 20 (see Figure 14), and then installing and temporarily fixing the support portion piezoelectric element 100 so that the second electrode of the support portion piezoelectric element 100 contacts the second electrode conductive adhesive 125 and the peripheral region of the lower surface (the surface close to the disk surface) of the support portion piezoelectric element 100 contacts the second insulating adhesive 111 for temporary fixing (see Figure 15).

[0134] 3, 5 and 13 to 15 denotes a ring fixed to the upper surface of the insulating layer 71 so as to surround the through-hole 712a of the extension region 712 in a plan view, and prevents the conductive adhesive 125 for the second electrode filled in the access opening 29 and the through-hole 712a from flowing out before hardening.

[0135] In the fixing process for the piezoelectric element for support portion, in the fixing process performed after the temporary fixing process, the first insulating adhesive 110 is filled into the gaps 112 (see Figures 10 and 15) between the piezoelectric element for support portion 110 and the base end support portion 11, the tip end support portion 13 and the weak rigidity support portion 13, respectively, to fix the piezoelectric element for support portion 100 in a predetermined position (see Figure 9).

[0136] In the support portion piezoelectric element fixing process, after the fixing step, the insulation calculation step, the first electrode electrical connection step, the conductivity calculation step, and the determination step are performed in this order.

[0137] Next, the process of fixing the piezoelectric element for the flexure portion will be described. FIG. 16 is a plan view corresponding to FIG. 8, showing a state in which the load beam portion 50 has been removed. FIG. 17 shows a cross-sectional view taken along line XVII-XVII in FIG.

[0138] As shown in Figures 16 and 17, the piezoelectric element 150 for the flexure portion is arranged on the upper surface (the surface opposite the magnetic disk) of the air area 715 of the insulating layer 71 in the wiring body 70 within the opening 69 defined by the gimbal area 610 and the pair of gimbal support pieces 620.

[0139] FIG. 18 is a plan view corresponding to FIG. 16, showing a state in which the flexure portion piezoelectric element 150 has been removed. FIG. 19 shows a cross-sectional view taken along line XIX-XIX in FIG.

[0140] As described above, the wiring body 70 has the insulating layer 71 adhered to the underside (the side closest to the magnetic disk) of the flexure substrate 61, and the conductor layer 73 adhered to the underside of the insulating layer 71.

[0141] As shown in FIGS. 18 and 19, the insulating layer 71 is provided with the air space 715 which is away from the support of the flexure substrate 61 and extends into the opening 69 .

[0142] The air region 715 has a first electrode through hole 715a that penetrates the upper and lower surfaces near the first end, which is on one side of the suspension longitudinal direction of the piezoelectric element 150 for the flexure portion, and a second electrode through hole 715b that penetrates the upper and lower surfaces at a position that overlaps with the piezoelectric element 150 for the flexure portion in a planar view.

[0143] The flexure portion piezoelectric element wiring 736 in the conductor layer 73 has a flexure portion piezoelectric element terminal region 737 that is accessible from above via the first electrode through hole 715a.

[0144] Furthermore, the wiring body 70 has a grounding metal portion 77 (see Figures 3 and 17, etc.) provided on the underside of the insulating layer 71, insulated from the conductor layer 73 and accessible from above via the second electrode through hole 715b.

[0145] The grounding metal portion 77 is preferably made of the same material as the conductor layer 73 and is formed simultaneously when the conductor layer 73 is formed on the lower surface of the insulating layer 71 .

[0146] In the magnetic head suspension 1 having such a configuration, the area of ​​the flexure portion piezoelectric element terminal area 737 exposed through the first electrode through hole 715a forms the first electrode connection area of ​​the flexure portion piezoelectric element 150, and the grounding metal portion 77 forms the second electrode connection area to which the second electrode of the flexure portion piezoelectric element 150 is electrically connected.

[0147] The flexure portion piezoelectric element fixing process includes the fixing step, the insulation calculation step, the first electrode electrical connection step, the conductivity calculation step, and the determination step, as well as a second electrode electrical connection step and a piezoelectric element second end fixing step. The second electrode electrically connecting step is carried out in parallel with the fixing step.

[0148] FIG. 20 is a cross-sectional view corresponding to FIG. 19, showing a state midway through the fixing step and the second electrode electrical connection step which are carried out in parallel. FIG. 21 is a plan view corresponding to FIGS. 16 and 18, showing a state after the fixing step and the second electrode electrical connection step have been completed. FIG. 22 shows a cross-sectional view taken along line XXII-XXII in FIG.

[0149] In detail, the fixing step in the process of fixing the piezoelectric element for the flexure portion involves applying the first insulating adhesive 110 to the portion of the upper surface of the aerial region 715 where the first longitudinal end of the piezoelectric element for the flexure portion 150 will be placed (see Figure 20), and then placing the piezoelectric element for the flexure portion 150 so that the first longitudinal end of the piezoelectric element for the flexure portion 150 is in contact with the first insulating adhesive 110.

[0150] The second electrode electrical connection process is configured to fill the second electrode through hole 715b, the underside opening of which is blocked by the grounding metal portion 77, with a second electrode conductive adhesive 125 (see Figure 20), and then install the flexure portion piezoelectric element 150 in the air area 715.

[0151] That is, the fixing step and the second electrode electrical connection step, which are carried out in parallel, are carried out by applying the first insulating adhesive 110 to the upper surface of the air space 715 and filling the second electrode through-holes 715b with the second electrode conductive adhesive 125, and then placing the flexure portion piezoelectric element 150 at a predetermined position on the upper surface of the air space 715. ConnectThe flexure portion piezoelectric element 150 is configured to be fixed to the upper surface of the insulating layer 71 by the first insulating adhesive 110 while being electrically connected to the grounding metal portion 77 which acts as a ground conductive area (see Figure 22).

[0152] In the magnetic head suspension 1, as shown in Figures 18, 21 and 22, the entire first electrode connection area (i.e., the area of ​​the flexure portion piezoelectric element terminal area 737 exposed through the first electrode through hole 715a) is set in the inspection area 200, and the first insulating adhesive 110 covers a portion of the inspection area 200.

[0153] Therefore, in the flexure portion piezoelectric element fixing process, the insulation calculation process, which is performed after the fixing process and the second electrode electrical connection process, calculates the amount of the first insulating adhesive 110 located on the area of ​​the flexure portion piezoelectric element terminal area 737 that is exposed through the first electrode through hole 715a.

[0154] The piezoelectric element second end fixing process is performed at any timing after the second electrode electrical connection process, and is configured to fix the second longitudinal end of the flexure portion piezoelectric element 150 to the wide portion 612 of the gimbal region 610 via another second insulating adhesive 115 (see Figures 16 and 17). [Explanation of symbols]

[0155] 1 Magnetic head suspension 10 Support part 11 Proximal support part 13 Tip side support part 15 Low rigidity support part 19 Opening 20 Support Plate 29 Access opening 40 Load bending section 41 Leaf spring 50 Load beam section 53 Dimples 60 Flexure section 61 Flexure board 62 Load beam attachment area 63 Flexure tip area 69 Opening 70 Wiring body 71 Insulating layer 73 Conductor layer 77 Metal part for grounding 90 Magnetic head slider 100 Piezoelectric element for support portion 110 First insulating adhesive 111 Second insulating adhesive 115 Other second insulating adhesives 120 Conductive adhesive for first electrode 125 Conductive adhesive for second electrode 150 Piezoelectric element for flexure section 200 Inspection Area 610 Gimbal Area 615 Low rigidity part 620 Gimbal support piece 712 Extension area of ​​insulating layer 712a Through hole 715 Aerial Area 715a Through hole for first electrode 715b Through hole for second electrode 730 Signal Wiring 734 Piezoelectric element wiring for support part 735 Piezoelectric element terminal area for support 736 Piezoelectric element wiring for flexure part 737 Piezoelectric element terminal area for flexure part L Suspension longitudinal center line

Claims

1. A method for inspecting electrical connectivity of a piezoelectric element that is applied when manufacturing a magnetic head suspension, the magnetic head suspension including a piezoelectric element that slightly moves a gimbal area on which a magnetic head slider is mounted in a seek direction parallel to a disk surface, the piezoelectric element being fixed at a predetermined installation position by a first insulating adhesive, and a predetermined first electrode terminal area of ​​a first electrode on one side in a thickness direction of the piezoelectric element being electrically connected to a predetermined first electrode connection area by a first electrode conductive adhesive that covers the first insulating adhesive in a bridge shape, an insulation calculation step of calculating an amount of the first insulating adhesive present on an inspection area set to include a part or all of at least one of the first electrode terminal area and the first electrode connection area after the piezoelectric element is fixed to the predetermined installation position with the first insulating adhesive; a conductivity calculation step of calculating an amount of the conductive adhesive for the first electrode present on the inspection area after electrically connecting the first electrode terminal area to the first electrode connection area with the conductive adhesive for the first electrode; A method for inspecting the electrical connectivity of a piezoelectric element, characterized by comprising a determination process for determining the electrical connectivity between the first electrode and the first electrode connection area based on the difference between the calculated value in the conductivity calculation process and the calculated value in the insulation calculation process.

2. 2. The method of claim 1, wherein the inspection area is set based on a reference point for installing the piezoelectric element.

3. the insulation calculation step and the conductivity calculation step are configured to calculate a plane area of ​​a portion of the inspection area that is covered with a corresponding adhesive, based on a two-dimensional image of the inspection area captured by a two-dimensional imaging device; 3. The method for inspecting the electrical connectivity of a piezoelectric element according to claim 1, wherein the determination process determines the electrical connectivity between the first electrode and the first electrode connection region based on the difference between the planar area of ​​the conductive adhesive for the first electrode calculated by the conductivity calculation process and the planar area of ​​the first insulating adhesive calculated by the insulation calculation process.

4. the insulation calculation step and the conductivity calculation step are configured to calculate a volume of the corresponding adhesive present on the inspection area based on a three-dimensional image of the inspection area captured by a three-dimensional imaging device; 3. The method for inspecting the electrical connectivity of a piezoelectric element according to claim 1, wherein the determination process determines the electrical connectivity between the first electrode and the first electrode connection region based on the difference between the volume of the conductive adhesive for the first electrode calculated by the conductivity calculation process and the volume of the first insulating adhesive calculated by the insulation calculation process.

5. 5. The method for testing the electrical connectivity of a piezoelectric element according to claim 3, wherein the insulation calculation process and the conductivity calculation process are configured to perform photographing using the photographing device while the inspection area is irradiated with ultraviolet light by an ultraviolet irradiation device.

6. A method for manufacturing a magnetic head suspension, comprising: a piezoelectric element for slightly moving a gimbal region on which a magnetic head slider is mounted in a seek direction parallel to a disk surface; the piezoelectric element being fixed at a predetermined installation position by a first insulating adhesive; and a predetermined first electrode terminal region of a first electrode on one side in a thickness direction of the piezoelectric element being electrically connected to a predetermined first electrode connection region by a first electrode conductive adhesive covering the first insulating adhesive in a bridge shape, a fixing step of fixing the piezoelectric element to the predetermined installation position with the first insulating adhesive; an insulation calculation step of calculating the amount of the first insulating adhesive present on an inspection area set to include a part or all of at least one of the first electrode terminal area and the first electrode connection area; a first electrode electrical connection step of applying a predetermined amount of the first electrode conductive adhesive to electrically connect the first electrode terminal region to the first electrode connection region; a conductivity calculation step of calculating the amount of the conductive adhesive for the first electrode present on the inspection area; A method for manufacturing a magnetic head suspension, characterized by including a determination process for determining the electrical connectivity between the first electrode and the first electrode connection region based on the difference between the calculated value in the conductivity calculation process and the calculated value in the insulation calculation process.

7. A method for manufacturing a magnetic head suspension, comprising: a piezoelectric element for slightly moving a gimbal region on which a magnetic head slider is mounted in a seek direction parallel to a disk surface; the piezoelectric element being fixed at a predetermined installation position by a first insulating adhesive; and a predetermined first electrode terminal region of a first electrode on one side in a thickness direction of the piezoelectric element being electrically connected to a predetermined first electrode connection region by a first electrode conductive adhesive covering the first insulating adhesive in a bridge shape, a fixing step of fixing the piezoelectric element to the predetermined installation position with the first insulating adhesive; an insulation calculation step of calculating the amount of the first insulating adhesive present on an inspection area set to include a part or all of at least one of the first electrode terminal area and the first electrode connection area; an application amount calculation step of calculating an application amount of the first electrode conductive adhesive for electrically connecting the first electrode terminal region to the first electrode connection region based on the calculation result of the insulation calculation step; A method for manufacturing a magnetic head suspension, characterized by comprising a first electrode electrical connection process for applying the amount of conductive adhesive for the first electrode calculated by the application amount calculation process to electrically connect the first electrode terminal area to the first electrode connection area.

8. a conductivity calculation step of calculating the amount of the conductive adhesive for the first electrode present on the inspection area; 8. A method for manufacturing a magnetic head suspension as described in claim 7, further comprising a determination process for determining the electrical connectivity between the first electrode and the first electrode connection region based on the difference between the calculated value in the conductivity calculation process and the calculated value in the insulation calculation process.

9. 9. The method for manufacturing a magnetic head suspension according to claim 6, wherein the inspection area is set based on a reference point for installing the piezoelectric element.

10. 10. A method for manufacturing a magnetic head suspension as described in any one of claims 6 to 9, characterized in that the calculation process is configured to calculate the planar area of ​​the portion of the inspection area covered by the corresponding adhesive based on a two-dimensional image of the inspection area taken by a two-dimensional imaging device.

11. 10. A method for manufacturing a magnetic head suspension as described in any one of claims 6 to 9, characterized in that the calculation process is configured to calculate the volume of the corresponding adhesive present on the inspection area based on a three-dimensional image of the inspection area taken by a three-dimensional imaging device.

12. 12. The method for manufacturing a magnetic head suspension according to claim 10, wherein the calculation step is configured to perform photography by the photography device in a state where ultraviolet light is irradiated onto the inspection area by an ultraviolet light irradiation device.

13. the magnetic head suspension comprises: a support section that is swung by a main actuator directly or indirectly around a swing center in a seek direction parallel to a disk surface; a load bending section whose base end is supported by the support section and has a leaf spring that generates a pressing load that presses the gimbal area toward the disk surface; a load beam section that is supported by the support section via the load bending section and transmits the pressing load to the gimbal area; a flexure section that includes a flexure substrate having the gimbal area and a wiring body fixed to the flexure substrate; and a pair of the piezoelectric elements; the support section includes a base-end support section having the swing center, a tip-end support section supporting a base end of the load bending section, and a weak-rigidity support section connecting the tip-end support section and the base-end support section so that the tip-end support section can swing relative to the base-end support section in both directions in the seek direction with respect to a center line of the suspension longitudinal direction, the weak-rigidity support section having openings that enable the pair of piezoelectric elements to be arranged symmetrically on either side of the center line of the suspension longitudinal direction; a support plate is fixed to a lower surface of the support portion facing the disk surface, the support plate having access openings for exposing portions of the lower surfaces of the pair of piezoelectric elements arranged in the openings to the disk surface side, and supporting the lower surfaces of the pair of piezoelectric elements; the wiring body includes an insulating layer provided on a lower surface of the flexure substrate facing the disk surface, and a conductor layer provided on the insulating layer; the insulating layer has an extension region that extends into the access opening in a plan view; the conductor layer has a signal wiring electrically connected to the magnetic head slider, and a piezoelectric element wiring for supplying a drive voltage to the piezoelectric element, the piezoelectric element wiring having a piezoelectric element terminal region located in the extension region; a second electrode on the other side in the thickness direction of the piezoelectric element is electrically connected to the piezoelectric element terminal area via a second electrode conductive adhesive material filled in the access opening and the through hole provided in the extension area; The manufacturing method further includes a temporary fixing step of, before the fixing step, applying a conductive adhesive for a second electrode to the access opening and the through hole and applying a second insulating adhesive for temporary fixing to the support plate, and then installing the piezoelectric element such that the second electrode of the piezoelectric element contacts the conductive adhesive for the second electrode and a peripheral region of the lower surface of the piezoelectric element contacts the second insulating adhesive for temporary fixing, the fixing step is configured to apply the first insulating adhesive to gaps between the piezoelectric element and each of the base-end support portion, the tip-end support portion, and the low-rigidity support portion; 13. The method for manufacturing a magnetic head suspension according to claim 6, wherein the inspection area is set on the first electrode or the support portion.

14. the magnetic head suspension comprises: a support section that is swung by a main actuator directly or indirectly around a swing center in a seek direction parallel to a disk surface; a load bending section whose base end is supported by the support section and has a leaf spring that generates a pressing load that presses the gimbal area toward the disk surface; a load beam section that is supported by the support section via the load bending section and transmits the pressing load to the gimbal area; a flexure section that includes a flexure substrate having the gimbal area and a wiring body fixed to the flexure substrate; and a pair of the piezoelectric elements; the flexure substrate includes a load beam portion fixing region that is fixed to the load beam portion in an overlapping state, and a flexure tip region that extends from the load beam portion fixing region toward a tip side away from the state supported by the load beam portion, the flexure tip region has the gimbal region, on whose upper surface opposite to the disk surface a dimple provided on the load beam portion abuts and on whose lower surface facing the disk surface the magnetic head slider is mounted, and a pair of gimbal support pieces extending from the load beam portion fixing region symmetrically with respect to each other with respect to a center line of the suspension longitudinal direction, and supporting the gimbal region so that the gimbal region can swing in the roll direction and the seek direction with the dimple as a fulcrum; the gimbal region and the pair of gimbal support pieces are configured to form openings that allow the pair of piezoelectric elements to be arranged symmetrically on either side of a center line in the longitudinal direction of the suspension, a weak rigidity portion is provided in the gimbal region, which allows the gimbal region to swing in both directions in the seek direction with the dimple as a fulcrum due to the expansion and contraction of the pair of piezoelectric elements; the wiring body includes an insulating layer fixed to a lower surface of the flexure substrate facing the disk surface, and a conductor layer provided on the lower surface of the insulating layer; the insulating layer has an air-filled region extending into the opening away from support by the flexure substrate; the conductor layer has signal wiring electrically connected to the magnetic head slider and piezoelectric element wiring for supplying a drive voltage to the piezoelectric element; the piezoelectric element wiring has a piezoelectric element terminal region located in the air space, the wiring body further includes a grounding metal portion provided on a lower surface of the aerial region in a state insulated from the conductor layer, a first electrode through-hole and a second electrode through-hole are provided in the air-spaced area, exposing the piezoelectric element terminal area and the grounding metal portion to an upper surface side of the insulating layer, respectively; a region of the piezoelectric element terminal region exposed through the first electrode through hole forms the first electrode connection region; a second electrode on the other side in the thickness direction of the piezoelectric element is electrically connected to the grounding metal portion via a second electrode conductive adhesive material filled in the second electrode through hole, The manufacturing method further comprises: a second electrode electrical connection step carried out in parallel with the fixing step; a piezoelectric element second end fixing step performed at an arbitrary timing after the second electrode electrical connection step, the fixing step and the second electrode electrical connection step, which are carried out in parallel, are configured to fix the first end of the piezoelectric element to the upper surface of the airspace with the second electrode electrically connected to the grounding metal portion by applying the first insulating adhesive to a portion of the upper surface of the airspace where the first longitudinal end of the piezoelectric element will be placed and filling the second electrode through-hole with the second electrode conductive adhesive, and then placing the piezoelectric element on the upper surface of the airspace; the piezoelectric element second end fixing step is configured to fix a second longitudinal end of the piezoelectric element to the gimbal region via another second insulating adhesive, 13. The method for manufacturing a magnetic head suspension according to claim 6, wherein the inspection area is set in an area of ​​the piezoelectric element terminal area that is exposed through the first electrode through hole.

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