JP5201174B2 - Suspension substrate and manufacturing method thereof - Google Patents

Description

  The present invention relates to a suspension substrate in which an influence of a crack generated in an insulating layer is reduced in a boundary region between a region where a metal supporting substrate is present and a region where a metal supporting substrate is not present.

  In recent years, due to the spread of the Internet and the like, there has been a demand for an increase in the amount of information processing of personal computers and an increase in information processing speed. Increasing information transmission speed is required. For this reason, higher functions are also required for suspension substrates (flexures) used in HDDs.

  As such a suspension substrate, for example, Patent Document 1 discloses a flexure having a slider bonding pad portion (tang portion), an outrigger, and a cross bar. Furthermore, in patent document 1, the wiring is formed on the outrigger. Patent Document 2 discloses a suspension for a disk device in which a wiring layer is disposed between a tongue portion and an outrigger portion. Patent Document 3 discloses an out-trace type flexure through which a trace member (wiring layer) bypasses the outside of the outrigger portion. Patent Document 4 discloses a gimbal structure having a trace support tab that supports a conductive trace (wiring layer).

JP 2007-213793 A JP 11-39626 A JP 2007-287296 A JP 2008-41241 A

  In a conventional suspension substrate, a wiring layer is formed on a metal support substrate via an insulating layer. In recent years, part of the metal support substrate has been actively removed along with the enhancement of the function of the suspension substrate (for example, the reduction in rigidity). If a part of the metal support substrate is removed, stress is likely to concentrate on the insulating layer present on the boundary region between the region where the metal support substrate is present and the region where the metal support substrate is not present, and cracks are likely to occur in the insulating layer. There's a problem.

  The present invention has been made in view of the above problems, and provides a suspension substrate in which the influence of cracks generated in an insulating layer is reduced in a boundary region between a region where a metal support substrate is present and a region where a metal support substrate is not present. The main purpose.

  In order to solve the above problems, in the present invention, a metal support substrate, an insulating layer formed on the metal support substrate, a wiring layer formed on the insulating layer, and the wiring layer are covered. A suspension substrate having a formed cover layer, wherein the metal support substrate, the insulating layer, the wiring layer, and the first structure portion having the cover layer are formed continuously from the first structure portion. And the second structure part where the metal support substrate does not exist, and in the boundary region between the first structure part and the second structure part, from the end part of the wiring layer in plan view, the end part of the insulating layer And the width from the end of the wiring layer to the end of the cover layer is locally large.

  According to the present invention, in the boundary region, at least one of the width from the end of the wiring layer to the end of the insulating layer and the width from the end of the wiring layer to the end of the cover layer is shown in plan view. By increasing the size locally, the influence of cracks generated in the insulating layer can be reduced. Therefore, disconnection of the wiring layer due to stress concentration can be prevented.

  In the above invention, it is preferable that the position of the end portion of the insulating layer and the position of the end portion of the cover layer coincide with each other in the boundary region. This is because the occurrence of cracks themselves can be suppressed.

  In the said invention, it is preferable that the curve structure part is formed in at least one of the said insulating layer and the said cover layer so that the said boundary area may be included in planar view. This is because, due to the presence of the curved structure portion, it is possible to achieve stress distribution and further suppress the occurrence of cracks in the insulating layer in the boundary region.

  In the present invention, a metal support substrate, an insulating layer formed on the metal support substrate, a wiring layer formed on the insulating layer, and a cover layer formed so as to cover the wiring layer; A suspension substrate having a first structure portion having the metal support substrate, the insulating layer, the wiring layer, and the cover layer, and the first structure portion. A second structure part that does not exist, and in the boundary region between the first structure part and the second structure part, in the plan view, between the end of the wiring layer and the end of the insulating layer Provided is a suspension substrate in which a wiring layer is formed.

  According to the present invention, the influence of cracks generated in the insulating layer can be reduced by providing the auxiliary wiring layer in the boundary region between the end of the wiring layer and the end of the insulating layer in plan view. Therefore, disconnection of the wiring layer due to stress concentration can be prevented.

  In the above invention, the surface of the auxiliary wiring layer is preferably covered with the cover layer.

  In the said invention, it is preferable that the wiring plating part is formed in the surface of the said auxiliary wiring layer.

  In the above invention, in the boundary region, the width from the end of the wiring layer to the end of the insulating layer and the width from the end of the wiring layer to the end of the cover layer in plan view. At least one is preferably locally large. This is because the influence of cracks generated in the insulating layer can be further reduced.

  In the above invention, the metal support board includes a tongue portion for mounting an element and an outrigger portion positioned outside the tongue portion, and the wiring layer includes the tongue portion and the outrigger portion in plan view. It is preferable that it is formed between. This is because cracks are likely to occur in the insulating layer in the boundary region where such a wiring layer is formed, but the influence can be effectively reduced.

  In the said invention, it is preferable that the said metal support substrate has a cross bar which connects the said tongue part and the said outrigger part, and the said metal support substrate of a said 1st structure part is the said cross bar.

  In the said invention, it is preferable that the said metal support substrate has a trace support tab in the end surface at the side of the said tongue part of an outrigger part, and the said metal support substrate of a said 1st structure part is the said trace support tab.

  In the said invention, it is preferable that the said metal support substrate has a base part which supports the base of the said outrigger part, and the said metal support substrate of a said 1st structure part is the said base part.

  In the said invention, it is preferable that the said metal support substrate of a said 1st structure part is the said tongue part.

  In the present invention, a metal support substrate, an insulating layer formed on the metal support substrate, a wiring layer formed on the insulating layer, and a cover layer formed so as to cover the wiring layer; A first structure portion having the metal support substrate, the insulating layer, the wiring layer, and the cover layer, and a second structure portion formed continuously from the first structure portion and having no metal support substrate. A method for manufacturing a suspension substrate having a width from an end portion of the wiring layer to an end portion of the insulating layer in plan view in a boundary region between the first structure portion and the second structure portion, and A suspension comprising a step of forming at least one of the insulating layer and the cover layer so that at least one of a width from an end of the wiring layer to an end of the cover layer is locally increased. To provide a method of manufacturing a substrate.

  According to the present invention, in the boundary region, at least one of the width from the end of the wiring layer to the end of the insulating layer and the width from the end of the wiring layer to the end of the cover layer is local in plan view. By forming at least one of the insulating layer and the cover layer so as to be larger, it is possible to obtain a suspension substrate in which the influence of cracks generated in the insulating layer is reduced.

  In the above invention, it is preferable that the insulating layer and the cover layer are formed so that the position of the end portion of the insulating layer and the position of the end portion of the cover layer coincide with each other in the boundary region. This is because the occurrence of cracks themselves can be suppressed.

  In the present invention, a metal support substrate, an insulating layer formed on the metal support substrate, a wiring layer formed on the insulating layer, and a cover layer formed so as to cover the wiring layer; A first structure portion having the metal support substrate, the insulating layer, the wiring layer, and the cover layer, and a second structure portion formed continuously from the first structure portion and having no metal support substrate. A method for manufacturing a suspension substrate, comprising: an auxiliary portion between the end of the wiring layer and the end of the insulating layer in plan view in a boundary region between the first structure and the second structure; There is provided a method for manufacturing a suspension substrate, comprising a wiring layer forming step of forming a wiring layer.

  According to the present invention, according to the second embodiment, in the boundary region, by forming the auxiliary wiring layer between the end of the wiring layer and the end of the insulating layer, cracks generated in the insulating layer are reduced. A suspension substrate with reduced influence can be obtained.

  In the above invention, it is preferable that the wiring layer and the auxiliary wiring layer are simultaneously formed in the wiring layer forming step. This is because the manufacturing process can be simplified.

  In the above invention, the metal support substrate having a tongue portion for mounting an element and an outrigger portion located outside the tongue portion is formed, and the planar view, between the tongue portion and the outrigger portion, It is preferable to form a wiring layer. This is because cracks are likely to occur in the insulating layer in the boundary region where such a wiring layer is formed, but the influence can be effectively reduced.

  The suspension substrate of the present invention has an effect that the influence of cracks generated in the insulating layer can be reduced in the boundary region between the region where the metal support substrate is present and the region where the metal support substrate is not present.

It is a schematic diagram showing an example of a general suspension substrate. It is a schematic plan view which shows the vicinity of the element mounting area | region of the board | substrate for suspensions of a 1st embodiment. It is a schematic plan view which shows the vicinity of a cross bar. It is a schematic plan view explaining the suspension substrate of the first embodiment. It is a schematic sectional drawing explaining the board | substrate for suspensions of a 1st embodiment. It is a schematic plan view explaining the suspension substrate of the first embodiment. It is a schematic sectional drawing explaining the board | substrate for suspensions of a 1st embodiment. It is a schematic plan view explaining the metal support substrate in a first embodiment. It is a schematic plan view explaining the suspension substrate of the first embodiment. It is a schematic plan view explaining the suspension substrate of the first embodiment. It is a schematic diagram explaining the board | substrate for suspensions of a 2nd embodiment. It is a schematic diagram explaining the board | substrate for suspensions of a 2nd embodiment. It is a schematic plan view explaining the board | substrate for suspensions of a 2nd embodiment. It is a schematic sectional drawing which shows an example of the manufacturing method of the board | substrate for suspensions of a 1st embodiment. It is a schematic sectional drawing which shows the other example of the manufacturing method of the board | substrate for suspensions of a 1st embodiment. It is a schematic sectional drawing which shows an example of the manufacturing method of the board | substrate for suspensions of a 2nd embodiment.

  Hereinafter, the suspension substrate and the method for manufacturing the suspension substrate of the present invention will be described in detail.

A. Suspension Substrate The suspension substrate of the present invention is provided with a reinforcing portion that can reduce the influence of cracks generated in the insulating layer in the boundary region between the first structure portion and the second structure portion. It can be divided roughly into two embodiments according to the form of the reinforcing portion.

1. First Embodiment First, a first embodiment of the suspension substrate of the present invention will be described. The suspension substrate according to the first embodiment is formed so as to cover the metal supporting substrate, the insulating layer formed on the metal supporting substrate, the wiring layer formed on the insulating layer, and the wiring layer. A suspension substrate having a cover layer, wherein the metal support substrate, the insulating layer, the wiring layer, and the first structure portion having the cover layer are formed continuously from the first structure portion, and the metal And a width from an end portion of the wiring layer to an end portion of the insulating layer in a plan view in a boundary region between the first structure portion and the second structure portion. In addition, at least one of the widths from the end of the wiring layer to the end of the cover layer is locally large.

  FIG. 1 is a schematic view showing an example of a general suspension substrate. FIG. 1A is a schematic plan view of a suspension substrate, and FIG. 1B is a sectional view taken along line XX of FIG. In FIG. 1A, the cover layer is not shown for convenience. A suspension substrate 100 shown in FIG. 1A includes an element mounting region 101 formed at one tip portion, an external circuit board connection region 102 formed at the other tip portion, an element mounting region 101 and an external portion. And a plurality of wiring layers 103a to 103d for electrically connecting the circuit board connection region 102. The wiring layer 103a and the wiring layer 103b are a pair of wiring layers. Similarly, the wiring layer 103c and the wiring layer 103d are also a pair of wiring layers. One of these two wiring layers is a writing wiring layer, and the other is a reading wiring layer. On the other hand, as shown in FIG. 1B, the suspension substrate includes a metal support substrate 1, an insulating layer 2 formed on the metal support substrate 1, and a wiring layer 3 formed on the insulating layer 2. And a cover layer 4 covering the wiring layer 3.

  FIG. 2 is a schematic plan view showing the vicinity of the element mounting region of the suspension substrate of the first embodiment. In FIG. 2, for the sake of convenience, the description of the cover layer is omitted, and the insulating layer and the wiring layer in the upper half of the drawing are indicated by dotted lines. 2 includes a tongue portion 11 on which an element such as a magnetic head slider is mounted, an outrigger portion 12 positioned outside the tongue portion 11, and a crossbar 13 that couples the tongue portion 11 and the outrigger portion 12. And a base portion 15 that supports the base of the outrigger portion 12. Further, in regions A to D in FIG. 2, a first structure portion having a metal support substrate 1, an insulating layer 2, a wiring layer 3, and a cover layer (not shown), and continuously from the first structure portion, respectively. A second structure portion that is formed and does not have the metal support substrate 1 is formed.

  In the first embodiment, as shown in FIG. 2, the wiring layer 3 is preferably formed between the tongue portion 11 and the outrigger portion 12 in plan view. This is because, in the boundary region where such a wiring layer is formed, cracks are likely to occur in the insulating layer on the lower surface of the wiring layer, but the influence can be effectively reduced. Moreover, in patent document 1 mentioned above, providing a wiring layer on an outrigger part is described. On the other hand, in order to adjust the pitch and roll angle of the gimbal, there is a technique of irradiating a laser to the outrigger portion. When such a technique is applied to Patent Document 1, the wiring layer is likely to deteriorate due to the influence of heat by laser irradiation. In addition, the rigidity of the wiring layer becomes an obstacle to the adjustment of the pitch and roll angle of the gimbal. Therefore, it is preferable to arrange the wiring layer outside or inside the outrigger portion. Here, when the wiring layer is disposed outside the outrigger portion, as described in Patent Document 3, an out-trace type suspension substrate is formed. However, in the out-trace type suspension substrate, the wiring layer is a disk. Flight height control may be difficult because it is greatly affected by wind pressure during rotation. In addition, since there is no outrigger portion outside the wiring layer, the wiring layer is easily damaged. Thus, from the viewpoint of preventing the deterioration of the wiring layer due to the laser irradiation, the viewpoint of reducing the influence of the wind pressure during the disk rotation, and the viewpoint of preventing the wiring layer from being damaged, the wiring layer is viewed in plan view. It is preferably formed between the tongue part and the outrigger part.

On the other hand, FIG. 3 is a schematic plan view showing the vicinity of the crossbar. In FIG. 3, the wiring layer 3 is arranged so as to intersect with the crossbar 13. Here, the crossbar 13, the insulating layer 2, the wiring layer 3 and the cover layer (not shown) are laminated in this order, the first structure portion S ₁ , the crossbar 13 does not exist, the insulating layer 2, the wiring layer 3 and a cover layer (not shown) in the boundary area between the second structural portion S ₂ which are laminated in this order, there is a problem that cracks 51 in the insulating layer 2 present thereon is likely. The crack 51 is caused by stress concentration during use of the suspension substrate (for example, stress concentration due to vibration of an element such as a magnetic head slider) and stress concentration during manufacture of the suspension substrate (for example, the crossbar 13). Stress concentration due to liquid treatment after the formation of the stress, stress concentration during the transportation of the suspension substrate in the manufacturing stage), and the like. When a crack is generated and the crack progresses, it is assumed that the stress directly affects the wiring layer. In the worst case, the wiring layer may be corroded or disconnected.

  The suspension substrate of the first embodiment preferably has a locally large width from the end 31 of the wiring layer 3 to the end 21 of the insulating layer 2 in plan view in the boundary region (FIG. 4A). ). In the suspension substrate of the first embodiment, it is preferable that the width from the end portion 31 of the wiring layer 3 to the end portion 41 of the cover layer 4 is locally large in the boundary region in plan view (FIG. 4 ( b)). Although not shown, in the first embodiment, the width from the end 31 of the wiring layer 3 to the end 21 of the insulating layer 2 in the plan view, and the width of the cover layer 4 from the end 31 of the wiring layer 3 are shown. Both of the widths up to the end 41 may be locally large.

  In the first embodiment, “the width is locally large” can be defined as follows. Since the insulating layer is intended to insulate the wiring layer, it is basically formed according to the wiring pattern of the wiring layer. Therefore, for example, as shown in FIG. 4A, the base line of the insulating layer 2 can be specified. This baseline can be easily specified whether it is a straight line or a curved line. Therefore, if the width between the end portion 31 and the end portion 21 in the boundary region is larger than the width between the end portion 31 and the end portion 21 in the baseline, it is specified that “the width is locally large”. it can. The same applies to the cover layer in FIG.

  FIG. 5A is a cross-sectional view taken along line XX in FIG. In FIG. 4A, the width from the end 31 of the wiring layer 3 to the end 21 of the insulating layer 2 is locally large in the boundary region. On the other hand, FIGS. 5B and 5C correspond to the XX cross-sectional view of FIG. 4B, respectively. 5B, the width from the end 31 of the wiring layer 3 to the end 21 of the insulating layer 2 and the width from the end 31 of the wiring layer 3 to the end 41 of the cover layer 4 in the boundary region. Is locally large. In FIG. 5C, the width from the end 31 of the wiring layer 3 to the end 41 of the cover layer 4 is locally large in the boundary region. When the insulating layer in the first embodiment is formed by wet etching, for example, the cross-sectional shape of the insulating layer is usually a trapezoid.

Thus, according to the first embodiment, in the boundary region, in a plan view, the width from the end of the wiring layer to the end of the insulating layer, and the end of the wiring layer to the end of the cover layer By increasing at least one of the widths locally, the influence of cracks generated in the insulating layer can be reduced. Therefore, disconnection of the wiring layer due to stress concentration can be prevented. In particular, in recent years, thinning of the insulating layer has been demanded, and cracks tend to be easily generated in the insulating layer. However, according to the first embodiment, the influence of the cracks can be effectively reduced.
Hereinafter, the suspension substrate according to the first embodiment will be described separately for the suspension substrate member and the suspension substrate configuration.

(1) Suspension Board Member First, the suspension board member of the first embodiment will be described. The suspension substrate of the first embodiment has a metal support substrate, an insulating layer, a wiring layer, and a cover layer.

  The metal support substrate in the first embodiment functions as a support for the suspension substrate. The material of the metal support substrate is preferably a metal having spring properties, and specific examples include SUS. Moreover, although the thickness of a metal support substrate changes with kinds of the material, it exists in the range of 10 micrometers-20 micrometers, for example.

  The insulating layer in the first embodiment is formed on the metal support substrate. The material of the insulating layer is not particularly limited as long as it has insulating properties, and examples thereof include a resin. Examples of the resin include polyimide resin, polybenzoxazole resin, polybenzimidazole resin, acrylic resin, polyether nitrile resin, polyether sulfone resin, polyethylene terephthalate resin, polyethylene naphthalate resin, and polyvinyl chloride resin. Of these, polyimide resin is preferred. It is because it is excellent in insulation, heat resistance and chemical resistance. In addition, the material of the insulating layer may be a photosensitive material or a non-photosensitive material. The thickness of the insulating layer is, for example, preferably in the range of 5 μm to 30 μm, more preferably in the range of 5 μm to 18 μm, and still more preferably in the range of 5 μm to 12 μm.

  The wiring layer in the first embodiment is formed on the insulating layer. The material of the wiring layer is not particularly limited as long as it has conductivity, but for example, a metal can be cited, and copper (Cu) is particularly preferable. Moreover, the material of the wiring layer may be rolled copper or electrolytic copper. The thickness of the wiring layer is preferably in the range of 5 μm to 18 μm, for example, and more preferably in the range of 9 μm to 12 μm. A wiring plating portion may be formed on a part of the surface of the wiring layer. This is because the wiring layer can be prevented from being deteriorated (corrosion or the like) by providing the wiring plating portion. Among these, in the first embodiment, it is preferable that a wiring plating part is formed in a terminal part for connection to an element or an external circuit board. Although the kind of wiring plating part is not specifically limited, For example, Ni plating, Au plating, etc. can be mentioned. The thickness of the wiring plating portion is, for example, in the range of 0.1 μm to 4.0 μm.

  The cover layer in the first embodiment is formed so as to cover the wiring layer 3. By providing the cover layer, deterioration (corrosion etc.) of the wiring layer can be prevented. Examples of the material for the cover layer include the resins described as the material for the insulating layer described above, and among them, a polyimide resin is preferable. The material of the cover layer may be a photosensitive material or a non-photosensitive material. The thickness of the cover layer is preferably in the range of 2 μm to 30 μm, for example, and more preferably in the range of 2 μm to 10 μm.

(2) Configuration of Suspension Substrate Next, the configuration of the suspension substrate of the first embodiment will be described. The suspension substrate of the first embodiment has a first structure portion in which a metal support substrate, an insulating layer, a wiring layer, and a cover layer are laminated in this order. As the wiring layer in the first structure portion, a plurality of wiring layers having various functions can be used. Examples of wiring layers include a write wiring layer, a read wiring layer, a noise shield wiring layer, a crosstalk prevention wiring layer, a power supply wiring layer, a ground wiring layer, a flight height control wiring layer, and a sensor wiring. Layer, actuator wiring layer, heat assist wiring layer, and the like. In addition, the suspension substrate of the first embodiment has a second structure portion that is continuously formed from the first structure portion and does not have a metal support substrate. The second structure portion corresponds to, for example, a structure portion obtained by removing only the metal support substrate from the first structure portion.

In the first embodiment, in the boundary region, in a plan view, at least the width from the end of the wiring layer to the end of the insulating layer, and the width from the end of the wiring layer to the end of the cover layer are at least One of the features is that one is locally large. Here, as shown in FIG. 6 (a), if the width from the base line of the insulating layer 2 to the end portion 21 of the insulating layer 2 was set to W _1, the value of W ₁ is not less eg 30μm or more Preferably, it is 50 μm or more, more preferably 70 μm or more. The upper limit of the value of W ₁ is not particularly limited. 6A illustrates the case where the width from the end 31 of the wiring layer 3 to the end 21 of the insulating layer 2 is locally large, from the end of the wiring layer to the end of the cover layer. The same applies to the case where the width of is locally large.

  Further, as shown in FIG. 6B, the influence of cracks generated in the insulating layer can be reduced by increasing the width from the end 31 of the wiring layer 3 to the end 21 of the insulating layer 2 as a whole. Can do. Although not shown, similarly, the influence of cracks generated in the insulating layer can be reduced by increasing the overall width from the end of the wiring layer to the end of the cover layer. However, in order to adopt such a structure, it is necessary to have a space, and design restrictions are increased.

Further, as shown in FIG. 5B, the suspension substrate according to the first embodiment includes the width from the end portion 31 of the wiring layer 3 to the end portion 21 of the insulating layer 2 in the boundary region, and the wiring layer. It is preferable that the width from the end portion 31 of 3 to the end portion 41 of the cover layer 4 is locally large. This is because, by forming the protrusions with the insulating layer and the cover layer, the progress of cracks can be effectively suppressed in the laminated portion of both. In this case, the position of the end portion of the insulating layer and the position of the end portion of the cover layer may coincide with each other or may differ from each other, but preferably coincide with each other. This is because the occurrence of cracks themselves can be suppressed. The “matching” means that the position of the upper end portion of the insulating layer matches the position of the lower end portion of the cover layer. Further, the above “match” means not only exact match but also substantial match. “Substantial coincidence” means that, as shown in FIG. 7, the width W ₂ between the position of the lower end portion 4a of the cover layer 4 and the position of the upper end portion 2a of the insulating layer ₂ is 10 μm or less (preferably 5 μm or less). ). In addition, the position of the lower end part of the cover layer may be inside the position of the upper end part of the insulating layer, or may be outside.

  In addition, when an insulating layer is formed by wet etching and the position of the end of the insulating layer is matched with the position of the end of the cover layer in the boundary region, the angle θ of the lower end section of the insulating layer is increased. And the occurrence of cracks can be suppressed. The insulating layer and the cover layer usually have high adhesion from the viewpoint of ensuring durability as a product. Therefore, the etchant can be prevented from permeating between the two layers, and the angle θ of the lower end section of the insulating layer can be increased. By increasing the angle, the occurrence of cracks can be suppressed. In the first embodiment, the angle θ of the lower end section of the insulating layer is, for example, preferably 30 ° or more, more preferably 40 ° or more, and further preferably 50 ° or more.

  In the first embodiment, the material of the insulating layer and the material of the cover layer are preferably the same type of material. This is because the adhesion between the two layers becomes higher. When the adhesiveness is high, the etchant can be prevented from permeating between both layers, and the angle θ of the lower end section of the insulating layer can be increased. As a result, generation of cracks in the insulating layer can be suppressed. The same kind of material in the first embodiment refers to a material having a common basic skeleton. In particular, in the first embodiment, it is preferable that the material of the insulating layer and the material of the cover layer are both polyimide resins. Furthermore, the cover material is preferably a material having a lower etching rate with respect to the etchant than the material of the insulating layer.

  Next, the boundary area in the first embodiment will be described. The boundary region in the first embodiment is not particularly limited as long as it is a boundary region between the first structure portion and the second structure portion described above. Examples of the boundary area include the above-described areas A to D in FIG. Region A in FIG. 2 is an embodiment in which the metal support substrate of the first structure portion is the crossbar 13. Both ends of the cross bar 13 are boundaries between a region where the metal support substrate is present and a region where the metal support substrate is not present. In particular, since the region A is greatly affected by the vibration of the element when the suspension substrate is used, in this boundary region, the width from the end of the wiring layer to the end of the insulating layer in the plan view, and the wiring It is preferable that at least one of the widths from the end of the layer to the end of the cover layer is locally large. Furthermore, in the region A, the boundary region near the tongue portion 11 is easily affected by twisting or the like. Therefore, in the boundary region near the tongue portion 11, the end of the insulating layer extends from the end of the wiring layer. It is preferable that at least one of the width to the portion and the width from the end of the wiring layer to the end of the cover layer is locally large.

  In addition, the position of the cross bar in the first embodiment is not particularly limited as long as it is a position where the tongue portion and the outrigger portion can be connected, but is formed on the end surface of the tongue portion in the short direction of the suspension substrate. Preferably it is. In particular, in the first embodiment, as shown in FIG. 8, it is preferable that the crossbar 13 is formed so as to overlap with the transverse direction of the suspension substrate at the vibration center 16 of the element. This is because, for example, the vibration of the element can be minimized when HDI (Head Disk Interface) occurs.

  Moreover, the area | region B of FIG. 2 is an aspect whose metal support board | substrate of a 1st structure part is the trace support tab 14. FIG. Both ends of the trace support tab 14 become a boundary region between a region where the metal support substrate exists and a region where the metal support substrate does not exist. Similarly, a region C in FIG. 2 is an aspect in which the metal support substrate of the first structure portion is the base portion 15, and a region D in FIG. 2 is a tongue portion in which the metal support substrate of the first structure portion is the tongue portion. It is an aspect.

  In the first embodiment, as shown in FIG. 9A, it is preferable that the end 21 of the insulating layer 2 formed on the crossbar 13 is formed so as to reach the tongue 11. . Similarly, the end portion 21 of the insulating layer 2 formed on the cross bar 13 is preferably formed so as to reach the outrigger portion 12. Further, as shown in FIG. 9B, the end 21 of the insulating layer 2 formed on the support trace tab 14 is preferably formed so as to reach the outrigger portion 12. It is because generation | occurrence | production of a crack can be suppressed effectively by setting it as such a structure. In FIGS. 9A and 9B, the case where the width from the end 31 of the wiring layer 3 to the end 21 of the insulating layer 2 is locally large has been described. However, the cover layer extends from the end of the wiring layer. The same applies to the case where the width to the end of the is locally large.

  In the first embodiment, it is preferable that a curved structure portion is formed in at least one of the insulating layer and the cover layer so as to include a boundary region in plan view. This is because, due to the presence of the curved structure portion, it is possible to achieve stress distribution and further suppress the occurrence of cracks in the insulating layer in the boundary region. As such a curved structure part, for example, as shown in FIG. 10 (a), the curved structure part formed at the tip of the protrusion of the insulating layer 2, and the insulating layer 2 as shown in FIG. 10 (b). And a curved structure formed continuously from the base line. Although not shown in FIG. 10, a similar curved structure portion may be formed on the cover layer 4.

  In the first embodiment, examples of the element mounted in the element mounting region include a magnetic head slider, an actuator, and a semiconductor. The actuator may have a magnetic head or may not have a magnetic head.

2. Second Embodiment Next, a second embodiment of the suspension substrate of the present invention will be described. The suspension substrate according to the second embodiment is formed so as to cover the metal support substrate, the insulating layer formed on the metal support substrate, the wiring layer formed on the insulating layer, and the wiring layer. A suspension substrate having a cover layer, wherein the metal support substrate, the insulating layer, the wiring layer, and the first structure portion having the cover layer are formed continuously from the first structure portion, and the metal And a second structural part having no support substrate, and in a boundary region between the first structural part and the second structural part, between the end of the wiring layer and the end of the insulating layer in plan view In addition, an auxiliary wiring layer is formed.

  FIG. 11 is a schematic view showing an example of the suspension substrate of the second embodiment. FIG. 11A is a schematic plan view showing the vicinity of the crossbar as in FIG. 4A, and FIG. 11B is a cross-sectional view taken along the line XX in FIG. In the suspension substrate of the second embodiment, it is significant that the auxiliary wiring layer 7 is formed between the end portion 31 of the wiring layer 3 and the end portion 21 of the insulating layer 2 in plan view in the boundary region. Features.

As described above, according to the second embodiment, in the boundary region, by providing the auxiliary wiring layer between the end of the wiring layer and the end of the insulating layer in plan view, cracks generated in the insulating layer are reduced. The impact can be reduced. Therefore, disconnection of the wiring layer due to stress concentration can be prevented. In particular, in recent years, thinning of the insulating layer has been demanded, and cracks tend to be generated in the insulating layer. However, according to the second embodiment, the influence of the cracks can be effectively reduced.
Hereinafter, the suspension substrate according to the second embodiment will be described separately for the suspension substrate member and the suspension substrate configuration.

(1) Suspension Substrate Member First, the suspension substrate member of the second embodiment will be described. The suspension substrate according to the second embodiment has a metal support substrate, an insulating layer, a wiring layer, and a cover layer. Since these members are the same as the contents described in “1. First embodiment” above, description thereof is omitted here.

  The suspension substrate of the second embodiment has an auxiliary wiring layer. The auxiliary wiring layer may be made of the same material as the wiring layer or may be made of a different material, but the former is preferable. This is because the auxiliary wiring layer can be formed simultaneously with the formation of the wiring layer.

(2) Configuration of Suspension Substrate Next, the configuration of the suspension substrate of the second embodiment will be described. The suspension substrate of the second embodiment is characterized in that an auxiliary wiring layer is formed in the boundary region between the end of the wiring layer and the end of the insulating layer in plan view.

As shown in FIG. 11 (a) that, if the width of the auxiliary wiring layer was _{W 3,} the value of _{W 3} being that for example in the range of 10μm~50μm preferably, in the range of 15μm~30μm Is more preferable, and it is further preferable to be within the range of 15 μm to 20 μm. This is because if the value of W ₃ is too small, the progress of cracks may not be sufficiently suppressed, and if the value of W ₃ is too large, design restrictions increase.

  In the second embodiment, as shown in FIG. 11B, it is preferable that the position of the end portion of the insulating layer and the position of the end portion of the cover layer coincide with each other. This is because the occurrence of cracks themselves can be suppressed. The definition of “match” is the same as the contents described in “1. First embodiment”, and therefore the description thereof is omitted here.

  The position where the auxiliary wiring layer is formed is not particularly limited as long as it is between the end of the wiring layer (outermost wiring layer) and the end of the insulating layer. Among them, in the second embodiment, it is preferable that the surface of the auxiliary wiring layer 7 is covered with the cover layer 4 as shown in FIG. This is because deterioration (corrosion or the like) of the auxiliary wiring layer 7 can be prevented.

  12A, the position of the end 71 of the auxiliary wiring layer 7 and the position of the end 21 of the insulating layer 2 may coincide with each other. If these positions match, the occurrence of cracks can be suppressed. The “match” means that the position of the upper end portion of the insulating layer matches the position of the lower end portion of the auxiliary wiring layer. Further, the above “match” means not only exact match but also substantial match. “Substantially coincidence” means that the width between the position of the lower end portion of the auxiliary wiring layer and the position of the upper end portion of the insulating layer is 10 μm or less (preferably 5 μm or less). The position of the lower end portion of the auxiliary wiring layer may be inside the position of the upper end portion of the insulating layer, or may be outside.

  Further, when the insulating layer is formed by wet etching and the position of the end portion of the insulating layer is matched with the position of the end portion of the auxiliary wiring layer in the boundary region, the angle θ of the lower end section of the insulating layer is increased. And the occurrence of cracks can be suppressed. The insulating layer and the auxiliary wiring layer usually have high adhesion. Therefore, the etchant can be prevented from permeating between the two layers, and the angle θ of the insulating layer cross section can be increased. By increasing the angle, the occurrence of cracks can be suppressed. The angle θ of the lower end section of the insulating layer formed under the auxiliary wiring layer is, for example, preferably 30 ° or more, more preferably 40 ° or more, and further preferably 50 ° or more. .

  As shown in FIG. 12A, when the position of the end 71 of the auxiliary wiring layer 7 and the position of the end 21 of the insulating layer 2 coincide with each other, as shown in FIG. The wiring plating part 6 is preferably formed on the surface of the auxiliary wiring layer 7. This is because deterioration (corrosion etc.) of the auxiliary wiring layer can be prevented. In addition, if the material of the auxiliary wiring layer is a material having high corrosion resistance, it is not necessary to provide a wiring plating part. In addition, although not particularly illustrated as a method of forming the wiring plating portion, for example, a via portion that penetrates the insulating layer and electrically connects the auxiliary wiring layer to the metal supporting substrate is formed, and the metal supporting substrate and the via are formed. A method of feeding the auxiliary wiring layer from the portion and forming the wiring plated portion by an electrolytic plating method can be mentioned. Moreover, you may form a wiring plating part by the electroless-plating method.

  Further, the suspension substrate of the second embodiment may have the characteristics of the suspension substrate of the first embodiment. That is, in the boundary region, the auxiliary wiring layer is formed between the end of the wiring layer and the end of the insulating layer in plan view, and further, the width from the end of the wiring layer to the end of the insulating layer, In addition, at least one of the widths from the end of the wiring layer to the end of the cover layer may be locally large. As an example of this, as shown in FIG. 13, the auxiliary wiring layer 7 is formed between the end 31 of the wiring layer 3 and the end 21 of the insulating layer 2 in plan view. A suspension substrate in which the width from the end 31 to the end 21 of the insulating layer 2 is locally large can be mentioned.

B. Next, a method for manufacturing a suspension substrate according to the present invention will be described. The method for manufacturing a suspension substrate according to the present invention can be roughly divided into two embodiments.

1. First Embodiment First, a first embodiment of the method for manufacturing a suspension substrate of the present invention will be described. The manufacturing method of the suspension substrate according to the first embodiment includes a metal support substrate, an insulating layer formed on the metal support substrate, a wiring layer formed on the insulating layer, and the wiring layer. The formed cover layer, the metal support substrate, the insulating layer, the first structure portion having the wiring layer and the cover layer, and the first structure portion are continuously formed, and the metal support substrate does not exist. A method of manufacturing a suspension substrate having a second structure portion, wherein the end portion of the insulating layer is extended from the end portion of the wiring layer in plan view in the boundary region between the first structure portion and the second structure portion. Forming at least one of the insulating layer and the cover layer so that at least one of the width from the end of the wiring layer to the end of the cover layer is locally increased. That It is an butterfly.

  FIG. 14 is a schematic cross-sectional view showing an example of a manufacturing method of the suspension substrate of the first embodiment. FIG. 14 corresponds to the XX cross-sectional view of FIG. 4A, similarly to FIG. In FIG. 14, first, a laminated member having a metal supporting member 1X, an insulating member 2X formed on the metal supporting member 1, and a conductor member 3X formed on the insulating member 2X is prepared (FIG. 14 ( a)). Next, a predetermined resist pattern (patterned resist layer) is formed on the surface of the conductor member 3X using a dry film resist (DFR), and the conductor member 3X exposed from the resist pattern is wet etched. Then, the wiring layer 3 is formed (FIG. 14B). At this time, a similar resist pattern may be formed on the surface of the metal support member 1X, and jig holes and the like may be formed simultaneously with the wet etching.

  Thereafter, the cover layer 4 is formed so as to cover the wiring layer 3 (FIG. 14C). Next, a resist pattern 5 is formed so as to cover the cover layer 4 using DFR (FIG. 14D). Next, the insulating member 2X exposed from the resist pattern 5 is wet-etched to form the insulating layer 2 (FIG. 14E). In the method for manufacturing the suspension substrate according to the first embodiment, the insulating layer 2 is so formed that the width from the end 31 of the wiring layer 3 to the end 21 of the insulating layer 2 is locally increased during the wet etching. It is one of the characteristics to form. In FIG. 14 (e), the metal support member 1 </ b> X is processed by wet etching to form the metal support substrate 1.

  FIG. 15 is a schematic sectional view showing another example of the method for manufacturing the suspension substrate of the first embodiment. FIG. 15 corresponds to the XX cross-sectional view of FIG. 4B, similarly to FIG. 5B. The manufacturing method in FIG. 15 is basically the same as the manufacturing method in FIG. 14, but in FIG. 15C, a resist pattern is not formed using DFR or the like, and the cover layer 4 is used as a resist layer. Then, the insulating member 2X is wet etched. Thereby, it is possible to easily obtain a suspension substrate in which the position of the end portion 21 of the insulating layer 2 and the position of the end portion 41 of the cover layer 4 coincide.

  An example of the method for manufacturing the suspension substrate shown in FIG. 5C is an additive method. In the additive method, first, a patterned insulating layer 2 is formed on the surface of the metal support substrate 1. Thereafter, a resist pattern is formed on the insulating layer 2, the wiring layer 3 is formed on the insulating layer exposed from the resist pattern by plating, and then the end 31 of the wiring layer 3 to the end of the cover layer 4 The cover layer 4 may be formed so that the width up to 41 is locally increased.

  Thus, according to the first embodiment, in the boundary region, in the plan view, the width from the end of the wiring layer to the end of the insulating layer, and the end of the wiring layer to the end of the cover layer By forming at least one of the insulating layer and the cover layer so that at least one of the widths is locally increased, a suspension substrate can be obtained in which the influence of cracks generated in the insulating layer is reduced.

  Moreover, the manufacturing method of the suspension substrate of the first embodiment is not particularly limited as long as it has a step of forming at least one of an insulating layer and a cover layer in the predetermined shape. As an example of the method for manufacturing the suspension substrate of the first embodiment, the steps shown in FIGS. 14 and 15 described above will be described.

(1) Laminate member preparation process The laminate member preparation process in the first embodiment includes a metal support member, an insulating member formed on the metal support member, and a conductor member formed on the insulating member. It is a step of preparing a member. The laminated member in the first embodiment may be a commercially available laminated member, or may be formed by forming an insulating member and a conductor member on a metal support member.

(2) Wiring layer forming step In the wiring layer forming step in the first embodiment, a resist pattern is formed on the conductor member of the laminated member, and the conductor member exposed from the resist pattern is wet-etched to form a wiring layer. Is a step of forming. The type of etchant used for wet etching is preferably selected as appropriate according to the type of conductor member. For example, when the material of the conductor member is copper, an iron chloride-based etchant or the like can be used. In addition, when other layers are etched with the above-described etching solution, it is preferable to form a resist that protects from the etching solution as necessary.

(3) Cover layer forming step The cover layer forming step in the first embodiment is a step of forming a cover layer covering the wiring layer. The method for forming the cover layer is not particularly limited, and is preferably selected as appropriate according to the material of the cover layer. For example, when the material of the cover layer is a photosensitive material, a patterned cover layer can be obtained by exposing and developing the cover layer formed on the entire surface. In addition, when the cover layer material is a non-photosensitive material, a predetermined resist pattern is formed on the entire surface of the cover layer, and a portion exposed from the resist pattern is removed by wet etching. The cover layer can be obtained.

(4) Insulating layer forming step The insulating layer forming step in the first embodiment is a step of wet-etching the insulating member to form an insulating layer.

  The type of etching solution used for wet etching is preferably selected as appropriate according to the type of insulating layer. For example, when the material of the insulating layer is a polyimide resin, an alkaline etching solution or the like can be used.

  In the first embodiment, it is preferable to use the cover layer as a resist layer in the insulating layer forming step. This is because it is not necessary to provide a resist layer separately. Furthermore, the insulating layer and the cover layer usually have high adhesion from the viewpoint of ensuring durability as a product. Therefore, the etchant can be prevented from permeating between the two layers, and the angle θ of the lower end section of the insulating layer can be increased. When the cover layer is used as a resist layer, the cover layer material is preferably a material having a lower etching rate with respect to the etchant than the wiring layer material. This is because it is useful as a resist layer. Even if the etching rate of the material of the cover layer is the same as the etching rate of the material of the wiring layer or higher than the etching rate of the material of the wiring layer, for example, the thickness of the cover layer is sufficiently If secured, the cover layer can be used as a resist layer.

  In the first embodiment, the cover layer may not be used as the resist layer. In this case, it is necessary to provide a separate resist layer so as to cover the cover layer, but there is an advantage that the range of material selection is widened because it is not necessary to consider the etching rate of the material of the cover layer. In addition, when a solvent-type photoresist or an alkali development-peelable photoresist is used as a resist layer during the formation of the insulating layer, an alkaline etching solution generally used as an etching solution for a polyimide resin in particular dissolves the resist layer, The adhesion between the insulating layer and the resist layer may be reduced. Therefore, the etchant penetrates between the insulating layer and the resist layer, and the insulating layer in the penetrated portion is etched, so that the tapered shape of the insulating layer becomes remarkable.

  In particular, in the first embodiment, it is preferable to form the insulating layer and the cover layer so that the position of the end portion of the insulating layer matches the position of the end portion of the cover layer in the boundary region. This is because the occurrence of cracks themselves can be suppressed.

(5) Metal support board | substrate formation process The metal support board | substrate formation process in a 1st embodiment is a process of wet-etching the said metal support member, and forming a metal support board | substrate. Usually, in this step, the outer shape of the metal support member is processed. The type of etchant used for wet etching is preferably selected as appropriate according to the type of metal support member. For example, when the material of the metal support member is SUS, an iron chloride-based etchant or the like can be used. . In addition, when other layers are etched with the above-described etching solution, it is preferable to form a resist that protects from the etching solution as necessary.

(6) Other process The manufacturing method of the suspension substrate according to the first embodiment may include a wiring plating part forming step of forming a wiring plating part on a part of the wiring layer in addition to the above-described processes. . The method for forming the wiring plating portion may be an electrolytic plating method or an electroless plating method, but is preferably an electrolytic plating method. Moreover, the manufacturing method of the suspension substrate according to the first embodiment may include a via portion forming step of forming a via portion that penetrates the insulating layer and electrically connects the wiring layer and the metal support substrate. Examples of the method for forming the via portion include a plating method (electrolytic plating method, electroless plating method). In particular, when the wiring plating portion is formed in the auxiliary wiring layer, a step of forming a via for electrically connecting the auxiliary wiring layer to the metal supporting substrate is required.

2. Second Embodiment Next, a second embodiment of the method for manufacturing a suspension substrate according to the present invention will be described. The suspension substrate manufacturing method according to the second embodiment includes a metal support substrate, an insulating layer formed on the metal support substrate, a wiring layer formed on the insulating layer, and the wiring layer so as to cover the wiring layer. The formed cover layer, the metal support substrate, the insulating layer, the first structure portion having the wiring layer and the cover layer, and the first structure portion are continuously formed, and the metal support substrate does not exist. A method of manufacturing a suspension substrate having a second structure portion, wherein the end portion of the insulating layer is extended from the end portion of the wiring layer in plan view in the boundary region between the first structure portion and the second structure portion. In the meantime, a wiring layer forming step of forming an auxiliary wiring layer is provided.

  FIG. 16 is a schematic cross-sectional view showing an example of a manufacturing method of the suspension substrate of the second embodiment. FIG. 16 corresponds to the XX cross-sectional view of FIG. 11A, similarly to FIG. The manufacturing method in FIG. 16 is basically the same as the manufacturing method in FIG. 14, but in FIG. 16B, the auxiliary wiring layer 7 is formed simultaneously with the formation of the wiring layer 3. In FIG. 16C, the cover layer 4 is used as a resist layer, but a separate resist pattern may be formed using DFR or the like. Further, when obtaining a suspension substrate as shown in FIG. 12A, the auxiliary wiring layer 7 may be used as a resist layer.

  Thus, according to the second embodiment, in the boundary region, by forming the auxiliary wiring layer between the end of the wiring layer and the end of the insulating layer, the influence of cracks generated in the insulating layer is reduced. A reduced suspension substrate can be obtained.

  Moreover, the manufacturing method of the board | substrate for suspensions of a 2nd embodiment will not be specifically limited if it has a wiring layer formation process which forms an auxiliary wiring layer. The auxiliary wiring layer and the other wiring layers may be formed at the same time or as separate steps, but the former is preferable. This is because the manufacturing process can be simplified. Further, each step of the method for manufacturing the suspension substrate according to the second embodiment is the same as that described in “B. Method for manufacturing the suspension substrate 1. First embodiment”. Is omitted.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the technical idea described in the claims of the present invention has substantially the same configuration and exhibits the same function and effect regardless of the case. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be described more specifically with reference to examples.

[Example 1]
First, a laminated member having SUS304 (metal support member) having a thickness of 18 μm, a polyimide resin layer (insulating member) having a thickness of 10 μm, and an electrolytic copper layer (conductor member) having a thickness of 9 μm was prepared (FIG. 14A). . Next, a resist pattern was formed by simultaneously patterning using a dry film resist so that a jig hole whose positional accuracy is important on the SUS side and a wiring layer on the electrolytic copper side can be formed. Then, it etched using the ferric chloride liquid, and resist stripping was performed after the etching (FIG.14 (b)).

  Next, a polyimide precursor solution is coated on the patterned wiring layer with a die coater, dried, resist plate-making, etched at the same time as the polyimide precursor film, and then cured by heating in a nitrogen atmosphere. (Imidization) to form a cover layer (FIG. 14C). The cover layer was formed so as to cover the wiring layer, and the thickness of the cover layer formed on the wiring layer was 5 μm.

Next, in order to pattern the insulating member, resist plate-making was performed, and the exposed polyimide resin was removed by wet etching (FIG. 14D). Finally, in order to perform the external shape processing of the metal support member, resist plate-making was performed, and SUS in the exposed portion was removed by wet etching, thereby obtaining a suspension substrate (FIG. 14E). The width W ₁ (see FIG. 6A) from the base line of the insulating layer 2 to the end 21 of the insulating layer 2 was 80 μm.

[Example 2]
A suspension substrate was obtained in the same manner as in Example 1 except that a polyimide resin having an etching rate lower than that of the polyimide resin of the insulating member was used as the material of the cover layer, and the cover layer was used as a resist (see FIG. 15). ).

[Example 3]
First, a laminated member having SUS304 (metal support member) having a thickness of 18 μm, a polyimide resin layer (insulating member) having a thickness of 10 μm, and an electrolytic copper layer (conductor member) having a thickness of 9 μm was prepared (FIG. 16A). . Next, a resist pattern was formed by simultaneously patterning using a dry film resist so that a jig hole whose positional accuracy is important on the SUS side and a wiring layer and an auxiliary wiring layer on the electrolytic copper side can be formed. Then, it etched using the ferric chloride liquid, and resist stripping was performed after the etching (FIG.16 (b)). The width W ₃ (see FIG. 11A) of the auxiliary wiring layer 7 was 20 μm.

  Next, a polyimide precursor solution is coated on the patterned wiring layer with a die coater, dried, resist plate-making, etched at the same time as the polyimide precursor film, and then cured by heating in a nitrogen atmosphere. (Imidization) to form a cover layer (FIG. 16C). The cover layer was formed so as to cover the wiring layer, and the thickness of the cover layer formed on the wiring layer was 10 μm. Note that a polyimide resin having an etching rate lower than that of the polyimide resin of the insulating member was used as a material for the cover layer.

  Next, using the cover layer as a resist layer, the exposed portion of the polyimide resin is removed by wet etching. Finally, in order to perform the outer shape processing of the metal support member, resist plate-making is performed, and the exposed portion of SUS is performed by wet etching. This was removed to obtain a suspension substrate (FIG. 16D).

  DESCRIPTION OF SYMBOLS 1 ... Metal support substrate, 2 ... Insulating layer, 2a ... Upper end part of insulating layer, 3 ... Wiring layer, 4 ... Cover layer, 4a ... Lower end part of cover layer, 5 ... Resist layer (resist pattern), 6 ... Wiring plating Part: 7 ... auxiliary wiring layer, 11 ... tongue part, 12 ... outrigger part, 13 ... crossbar, 14 ... trace support tab, 15 ... base part, 16 ... vibration center, 51 ... crack

Claims (5)

A suspension substrate having a metal support substrate, an insulating layer formed on the metal support substrate, a wiring layer formed on the insulating layer, and a cover layer formed to cover the wiring layer. And
A first structure portion having the metal support substrate, the insulating layer, the wiring layer, and the cover layer; and a second structure portion formed continuously from the first structure portion and having no metal support substrate. And
In the boundary region between the first structure portion and the second structure portion, in plan view, the width from the end of the wiring layer to the end of the insulating layer, and the end of the cover layer from the end of the wiring layer At least one of the widths to the end is locally large,
The metal support substrate has a tongue portion for mounting an element, and an outrigger portion located outside the tongue portion;
The wiring layer is formed between the tongue portion and the outrigger portion in plan view,
The metal support board has a cross bar that connects the tongue part and the outrigger part,
The metal support substrate of the first structure portion is the crossbar;
The boundary regions are all four regions where the crossbar and the insulating layer intersect in plan view,
The position of the crossbar overlaps the short direction of the suspension substrate at the vibration center of the element,
The suspension substrate, wherein the cover layer is formed so as to straddle the boundary region.   2. The suspension substrate according to claim 1, wherein, in the boundary region, the position of the end portion of the insulating layer and the position of the end portion of the cover layer coincide with each other.   The suspension substrate according to claim 1, wherein a curved structure portion is formed in at least one of the insulating layer and the cover layer so as to include the boundary region in a plan view. . A metal support substrate, an insulating layer formed on the metal support substrate, a wiring layer formed on the insulating layer, a cover layer formed to cover the wiring layer, the metal support substrate, A suspension substrate manufacturing method comprising: a first structure portion having an insulating layer, the wiring layer, and the cover layer; and a second structure portion formed continuously from the first structure portion and having no metal support substrate. Because
In the boundary region between the first structure portion and the second structure portion, in plan view, the width from the end of the wiring layer to the end of the insulating layer, and the end of the cover layer from the end of the wiring layer Forming at least one of the insulating layer and the cover layer so that at least one of the widths to the end portion is locally increased,
The metal support substrate has a tongue portion for mounting an element, and an outrigger portion located outside the tongue portion;
The wiring layer is formed between the tongue portion and the outrigger portion in plan view,
The metal support board has a cross bar that connects the tongue part and the outrigger part,
The metal support substrate of the first structure portion is the crossbar;
The boundary regions are all four regions where the crossbar and the insulating layer intersect in plan view,
The position of the crossbar overlaps the short direction of the suspension substrate at the vibration center of the element,
The method for manufacturing a suspension substrate, wherein the cover layer is formed so as to straddle the boundary region.   The said insulating layer and the said cover layer are formed so that the position of the edge part of the said insulating layer and the position of the edge part of the said cover layer may correspond in the said boundary region. Of manufacturing a suspension substrate.

Images