JP5845631B2 - Flexure substrate for suspension, suspension, suspension with head, hard disk drive, and manufacturing method and inspection method for suspension flexure substrate - Google Patents

Description

  The present invention relates to a suspension flexure substrate used in a hard disk drive (HDD), a suspension, a suspension with a head, a hard disk drive, a manufacturing method of a suspension flexure substrate, and an inspection method.

  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, and along with this, the capacity of hard disk drives (HDD) incorporated in personal computers has increased. Increasing information transmission speed is required.

  A hard disk drive is a magnetic disk that is a magnetic recording medium, a spindle motor that rotates the magnetic disk at high speed, a magnetic head that reads or writes information on the magnetic disk, and each component that moves it while holding it with high precision. Drive control circuit and signal processing circuit.

  In addition, a component called a magnetic head suspension that supports the magnetic head used in this hard disk drive also has a signal line such as a copper wiring directly formed on a stainless steel spring from a conventional type in which a signal line such as a gold wire is connected. The so-called wireless suspension has been shifted to a wiring integrated type (flexure).

  As shown in FIG. 12, the wiring in such a flexure substrate for suspension is generally composed of an insulating layer in which a pair of reading wirings 104 and a pair of writing wirings 105 are formed on a metal support. Each is arranged on the surface.

  The pair of wirings as described above transmit, for example, an electrical signal by differential transmission, and a differential impedance that is a characteristic impedance of a differential transmission line as a distributed constant circuit exists between the pair of wirings. . The differential impedance is required to be lowered from the viewpoint of impedance matching as the impedance of the magnetic head and the preamplifier is lowered.

Conventionally, as shown in FIG. 13A, the pair of wirings as described above has been formed on the same surface so as to run side by side. However, in recent years, the impedance has been reduced and the wiring has been increased. With increasing density, stacked wiring as shown in FIG. 13B is also used (Patent Documents 1 and 2).
FIG. 13 schematically illustrates the configuration of the pair of read wirings 104 in FIG. 12, in which 104a and 104b are read wirings, 103a and 103b are connection terminal portions, and 111 is a magnetoresistive resistor. A reading element such as an element is shown.

Here, the configuration of the conventional multilayer wiring will be described using the example shown in FIG. 14A and 14B are explanatory views showing a configuration example of a conventional laminated wiring, in which FIG. 14A is a schematic plan view of a main part, and FIG.
In the example shown in FIG. 14, the first wiring composed of the first conductor 213 and the second composed of the first conductors 211 and 212 are formed on the same surface of the first insulating layer 231 formed on the metal support 221. A part of the wiring is formed, and a second wiring made of the second conductor 214 is formed on the first conductor 213 via the second insulating layer 232.
Further, the second wiring composed of the second conductor 214 is electrically connected to the first conductors 211 and 212 through the connection portion 215 formed in the opening provided in the second insulating layer 232.

Japanese Patent Laid-Open No. 9-22570 Japanese Patent Laid-Open No. 10-3632

  Here, in the multilayer wiring as described above, in order to achieve low impedance, it is necessary that the first lower wiring and the second upper wiring are formed within a predetermined relative position range. Therefore, it is necessary to guarantee the relative position by detecting the overlapping state.

  However, as shown in FIG. 14, when the stacked second conductor overlaps with the first conductor, an automatic measurement by a transmission type or a reflection type optical dimension measuring instrument or a dimension measuring instrument using ultraviolet rays, X-rays, or the like. It is difficult to measure the finished dimension of the second conductor and its coordinates by length measurement, and it has been difficult to guarantee the relative position accuracy in the conventional configuration.

  The present invention has been made in view of the above circumstances, and even when the stacked second conductor overlaps the first conductor, the relative position between the first wiring and the second wiring can be easily guaranteed. It is possible to provide a flexure substrate for suspension, a suspension, a suspension with a head, a hard disk drive, a manufacturing method of a flexure substrate for suspension, and an inspection method capable of achieving low impedance at low cost Objective.

  As a result of various researches, the present inventor has determined that a pair of structures for measuring relative positions formed from the first conductor and the second conductor in the multilayer wiring as described above are the first wiring and the first wiring, respectively. A structure for forming a relative position, formed from the first conductor, formed in a step of forming a first conductor pattern constituting a part of two wirings and a step of forming a second conductor pattern constituting a second wiring; The present invention has been completed by finding that the above problem can be solved by optically detecting the overlapping state of the relative position measuring structure formed from the second conductor.

That is, according to the first aspect of the present invention, the first conductor, the second insulating layer, and the second conductor are sequentially laminated at least partially on the first insulating layer formed on the metal support. The first conductor formed of the first conductor, the first conductor and the second conductor, and the first conductor and the through the connection portion formed in the opening provided in the second insulating layer. In a suspension flexure substrate having a second wiring having a configuration in which a second conductor is connected, a pair of structures for measuring the relative positions of the first wiring and the second wiring are the first wiring or the first wiring. The first conductor that does not constitute two wirings, and the second conductor that does not constitute the second wiring, and a structure for relative position measurement formed on the first conductor in plan view; and Relative position measurement formed on the second conductor Structures use is a flexible substrate for suspension, characterized in that it has a mutually different sizes point symmetrical shape.

The invention according to claim 2 of the present invention is characterized in that the relative position measuring structure is substantially ring-shaped, substantially frame-shaped, substantially cross-shaped, substantially circular, or substantially rectangular. A suspension flexure substrate according to claim 1 .

The invention according to claim 3 of the present invention, on the second wiring formed from the second conductor, for suspension according to claim 1 or claim 2, characterized in that the cover layer is formed It is a flexure substrate.

The invention according to claim 4 of the present invention, the structure for the relative position measurement made from said second conductor, and the structure for the relative position measurement made from said first conductor formed 4. The suspension flexure substrate according to claim 3 , wherein a part of the cover layer is removed so that the second insulating layer is exposed in the region that is formed. 5.

The invention according to claim 5 of the present invention, so that the first insulating layer in a region where the structure for the relative position measurement made from said first conductor and said second conductor is formed is exposed to a flexible substrate for suspension according to any one of claims 1 to 4, characterized in that the opening is formed on the metal support.

The invention according to claim 6 of the present invention is a suspension including the flexure substrate for suspension according to any one of claims 1 to 5 .

According to a seventh aspect of the present invention, there is provided a suspension with a head comprising the suspension according to the sixth aspect and a magnetic head slider mounted on the suspension.

According to an eighth aspect of the present invention, there is provided a hard disk drive including the suspension with a head according to the seventh aspect.

The invention according to claim 9 of the present invention, according to claim 1 be any suspension for flexure method for manufacturing a substrate according to the 5, the structure for measuring the relative position formed from the first conductor the body, the formed in the process and the same step of forming the first wiring from the first conductor, the structure for measuring the relative position formed from said second conductor, said from said second conductor second The suspension flexure substrate manufacturing method is characterized in that it is formed in the same step as the step of forming a part of the wiring.

The invention according to claim 10 of the present invention, according to claim 1 be any suspension for flexure testing method for a substrate according to the 5, the structure for measuring the relative position formed from the first conductor features and body, the overlapping state of the structure for the relative position measurement is formed from the second conductor by detecting optically, to guarantee a relative position of the second wiring and the first wiring This is a method for inspecting a flexure substrate for suspension.

According to the present invention, the pair of structures for measuring the relative position is formed of the first conductor and the second conductor, so that the structure for relative position measurement formed from the first conductor and the second conductor are formed. The relative position of the first wiring and the second wiring in the suspension flexure substrate of the laminated wiring configuration is assured by optically detecting the overlapping state of the relative position measuring structure formed from the conductor. Can do.
Therefore, it is possible to provide a suspension flexure substrate that achieves low impedance at low cost.

  Further, according to the manufacturing method of the present invention, the structure for measuring the relative position formed from the first conductor is formed in the same process as the process of forming the first wiring by processing the first conductor. Since the relative position measurement structure formed from the second conductor is formed in the same process as the process of forming the second wiring by processing the second conductor, a complicated process is required. The suspension flexure substrate having the structure for measuring the relative position of the first wiring and the second wiring in the multilayer wiring can be manufactured without increasing the number of the wirings.

  According to the inspection method of the present invention, the overlapping state of the relative position measurement structure formed from the first conductor and the relative position measurement structure formed from the second conductor is optically determined. By detecting this, it is possible to guarantee the relative positions of the first wiring and the second wiring without using a special measuring machine.

It is explanatory drawing which shows an example of the flexure substrate for suspensions which concerns on this invention, (a) is a schematic plan view of the principal part, (b) is AA sectional drawing in (a). It is explanatory drawing which shows the other example of the flexure board | substrate for suspensions which concerns on this invention, (a) is a schematic plan view of the principal part, (b) is BB sectional drawing in (a). It is explanatory drawing which shows the other example of the flexure board | substrate for suspensions concerning this invention, (a) is a schematic plan view of the principal part, (b) is CC sectional drawing in (a). It is explanatory drawing which shows the other example of the flexure board | substrate for suspensions which concerns on this invention, (a) is a schematic plan view of the principal part, (b) is DD sectional drawing in (a). It is explanatory drawing which shows the example of the structure for relative position measurement which concerns on this invention. It is explanatory drawing which shows the other example of the flexure board | substrate for suspensions which concerns on this invention, (a) is a schematic plan view of the principal part, (b) is EE sectional drawing in (a). It is explanatory drawing which shows the other example of the flexure board | substrate for suspensions which concerns on this invention, (a) is a schematic plan view of the principal part, (b) is FF sectional drawing in (a). It is a schematic sectional drawing which shows the other example of the flexure board | substrate for suspensions which concerns on this invention. It is a typical process figure showing an example of a manufacturing method of a flexure substrate for suspensions concerning the present invention. It is a typical process figure showing other examples of a manufacturing method of a flexure substrate for suspensions concerning the present invention. It is a typical process figure showing other examples of a manufacturing method of a flexure substrate for suspensions concerning the present invention. It is a schematic plan view showing an overview of a conventional suspension flexure substrate. It is explanatory drawing which shows the example of the conventional wiring structure, (a) shows single layer type wiring, (b) shows laminated type wiring. It is explanatory drawing which shows the example of the conventional flexure substrate for suspensions, (a) is a schematic plan view of the principal part, (b) is GG sectional drawing in (a).

  The suspension flexure substrate, suspension, suspension with head, hard disk drive, suspension flexure substrate manufacturing method and inspection method of the present invention will be described in detail below.

[Flexible substrate for suspension]
First, the suspension flexure substrate according to the present invention will be described.
(First embodiment)
FIG. 1 is an explanatory view showing an example of a first embodiment of a flexure substrate for suspension according to the present invention, (a) is a schematic plan view of the main part, and (b) is an A- It is A sectional drawing.
The suspension flexure substrate according to the present invention includes a first conductor, a second insulating layer, and a second conductor laminated on a first insulating layer formed on a metal support, and includes the first conductor. A suspension flexure substrate having a first wiring and a second wiring configured to connect the first conductor and the second conductor through a connection portion formed in an opening provided in the second insulating layer, The structure for measuring the relative position between the first conductor and the second conductor is formed of the first conductor and the second conductor.
In the present embodiment, the structure for measuring the relative position includes the first conductor in the portion where the first wiring and the second wiring are stacked via the second insulating layer, and the first conductor The outer shape of the structure for measuring the relative position formed on the first conductor is larger than the shape of the structure for measuring the relative position formed on the second conductor. It is characterized by having.

  For example, in the suspension flexure substrate 1 shown in FIG. 1, the first conductors 11, 12, and 13 are formed on the first insulating layer 31 formed on the metal support 21. A second insulating layer 32 is formed on the conductors 11, 12, and 13, a second conductor 14 is laminated on the second insulating layer 32, and further on the second conductor 14. A cover layer 41 is formed.

  And the structure 16a for the relative position measurement of the plane substantially circular shape comprised by the 1st conductor is the part by which the 1st wiring which consists of the 1st conductor 13, and the 2nd wiring which consists of the 2nd conductor 14 were laminated | stacked The structure 16b for measuring the relative position, which is formed on the first conductor 13 and has a substantially circular plane shape constituted by the second conductor, is composed of the first wiring made of the first conductor 13 and the second conductor 14. The second conductor 14 is formed in a portion where the second wiring is laminated.

Here, the center coordinates of the structure 16a and the center coordinates of the structure 16b are designed to be the same coordinates, and the planar shape of the structure 16a is larger by a predetermined amount than the planar shape of the structure 16b. It has an outer shape.
Therefore, for example, if the difference in size between the planar outer shape of the structure 16a and the planar outer shape of the structure 16b is designed within an allowable range of the relative positions of the first wiring and the second wiring, By optically detecting the overlapping state of the structure 16a and the structure 16b, the relative position between the first wiring made of the first conductor 13 and the second wiring made of the second conductor 14b can be guaranteed. .

  In FIG. 1, an example in which the planar shapes of the structures 16a and 16b are substantially circular is shown. However, in the present invention, any shape can be used as long as the relative positions can be measured by overlapping them. It may be. Further, the number of the structures 16a and 16b is not limited to one set, and a plurality of sets may be formed.

(Second Embodiment)
FIG. 2 is an explanatory view showing an example of a second embodiment of the flexure substrate for suspension according to the present invention, (a) is a schematic plan view of the main part, and (b) is a B- in (a). It is B sectional drawing.
In the present embodiment, the structure for measuring the relative position is formed on the first conductor and the second conductor at a portion where the first conductor and the second conductor are connected. The planar shape of the relative position measuring structure formed on the conductor has a larger outer shape than the planar shape of the relative position measuring structure formed on the second conductor.

  For example, in the suspension flexure substrate 1 shown in FIG. 2, a structure 16 a for measuring a relative position having a substantially circular plane formed by the first conductor is connected to the first conductor 11 and the second conductor 14. The first conductor 11 of the part and the first conductor 12 of the part where the first conductor 12 and the second conductor 14 are connected are formed for measuring the relative position of the plane substantially circular shape constituted by the second conductor. The structure 16b is formed on the second conductor 14 where the first conductor 11 and the second conductor 14 are connected, and the second conductor 14 where the first conductor 12 and the second conductor 14 are connected. .

Here, the center coordinates of the structure 16a and the center coordinates of the structure 16b are designed to be the same coordinates, and the planar shape of the structure 16a is larger by a predetermined amount than the planar shape of the structure 16b. It has an outer shape.
Therefore, for example, if the difference in size between the planar outer shape of the structure 16a and the planar outer shape of the structure 16b is designed within an allowable range of the relative positions of the first wiring and the second wiring, By optically detecting the overlapping state of the structure 16a and the structure 16b, the relative position between the first wiring made of the first conductor 13 and the second wiring made of the second conductor 14b can be guaranteed. .

  FIG. 2 shows an example in which the planar shapes of the structures 16a and 16b are substantially circular. However, in the present invention, any shape can be used as long as the relative positions can be measured by overlapping them. It may be. Further, the structures 16 a and 16 b may be provided only on one of the first conductor 11 and the first conductor 12 in addition to the case where the structures 16 a and 16 b are provided on both ends of the first conductor 11 and the first conductor 12.

(Third embodiment)
FIG. 3 is an explanatory view showing an example of the third embodiment of the flexure substrate for suspension according to the present invention, (a) is a schematic plan view of the main part, and (b) is a C- It is C sectional drawing.
In the present embodiment, the structure for measuring the relative position is formed at the connection portion of the first conductor and the second conductor at a portion where the first conductor and the second conductor are connected, The relative position measurement structure formed on the second conductor has an opening formed at the center of the connection portion of the second conductor, and the relative position measurement formed on the first conductor. The structure for use has an opening formed in the first conductor exposed from an opening formed in a central portion of the connection portion of the second conductor, and the relative structure formed in the second conductor The opening of the structure for position measurement has a larger inner diameter than the opening of the structure for relative position measurement formed in the first conductor.

  For example, in the suspension flexure substrate 1 shown in FIG. 3, the relative position measurement structure 16 a configured by the first conductor is the first conductor at the portion where the first conductor 11 and the second conductor 14 are connected. 11 and the first conductor 12 and the first conductor 12 at a portion where the second conductor 14 is connected, and the relative position measuring structure 16b constituted by the second conductor is connected to the first conductor 11 It is formed in the connection part 15 of the site | part to which the 2nd conductor 14 was connected, and the connection part 15 of the site | part to which the 1st conductor 12 and the 2nd conductor 14 were connected.

  The structure 16b has a substantially ring-like shape having an opening formed in the central portion of the connection portion 15, and the structure 16a is an opening formed in the central portion of the connection portion 15. And an opening formed in the first conductor 11 or the first conductor 12.

Here, the center coordinate of the opening of the structure 16a and the center coordinate of the opening of the structure 16b are designed to be the same coordinate, and the planar inner diameter of the opening of the structure 16b is The structure 16a has a diameter larger by a predetermined amount than the planar inner diameter of the opening.
Therefore, for example, if the difference between the planar inner diameter of the opening of the structure 16a and the planar inner diameter of the opening of the structure 16b is designed within the allowable range of the relative positions of the first wiring and the second wiring, the structure By optically detecting the overlapping state of the body 16a and the structure 16b, the relative position between the first wiring made of the first conductor 13 and the second wiring made of the second conductor 14b can be guaranteed.

  3 shows an example in which a set of structures 16a and 16b is provided at both ends of the first conductor 11 and the first conductor 12, but in addition to this, a set of structures 16a. 16b may be provided only on one side of the first conductor 11 or the first conductor 12.

(Fourth embodiment)
FIG. 4 is an explanatory view showing an example of the fourth embodiment of the flexure substrate for suspension according to the present invention, (a) is a schematic plan view of the main part, and (b) is a D- It is D sectional drawing.
In this embodiment, the structure for relative position measurement is formed by the first conductor that does not constitute the first wiring or the second wiring, and the second conductor that does not constitute the second wiring. The plane shape of the relative position measurement structure formed on the first conductor and the plane shape of the relative position measurement structure formed on the second conductor are point-symmetric shapes having different sizes. It is characterized by having.

  For example, in the suspension flexure substrate 1 shown in FIG. 4, the planar substantially ring-shaped structure 16a for relative position measurement constituted by the first conductor has the first wiring or the second wiring separately from the first wiring or the second wiring. A structure 16b for measuring a relative position, which is formed on the insulating layer 31 and has a substantially planar shape made of a second conductor, is formed on the second insulating layer 32 separately from the second wiring. .

The center coordinates of the structure 16a and the center coordinates of the structure 16b are designed to be the same coordinates, and the planar inner ring diameter of the structure 16a is the outer diameter of the planar shape of the structure 16b. It has a size larger than a predetermined amount.
Therefore, for example, the difference in size between the planar inner ring diameter of the structure 16a and the outer diameter of the planar shape of the structure 16b should be designed within the allowable range of the relative positions of the first wiring and the second wiring. For example, the relative position between the first wiring made of the first conductor 13 and the second wiring made of the second conductor 14b is ensured by optically detecting the overlapping state of the structure 16a and the structure 16b. Can do.

  FIG. 4 shows an example in which the planar shape of the structure 16a is a substantially ring shape and the planar shape of the structure 16b is a substantially circular shape. However, in the present invention, the shapes of the structures 16a and 16b are Any shape can be used as long as the relative position can be measured by overlapping. For example, as shown in FIGS. 5A to 5J, a substantially ring shape, a substantially frame shape, a substantially cross shape, a substantially circular shape, or a substantially It may be a point-symmetric shape having a different size, such as a rectangular shape. Further, the number of the structures 16a and 16b is not limited to one set, and a plurality of sets may be formed.

  Also, in FIG. 4, a planar substantially ring-shaped structure for relative position measurement 16a constituted by a first conductor, and a substantially circular planar structure for relative position measurement 16b constituted by a second conductor, However, in the present embodiment, the structure 16a and the structure 16b may be formed on the same surface.

FIG. 6 is an explanatory view showing another example of the fourth embodiment of the flexure substrate for suspension according to the present invention, (a) is a schematic plan view of the main part, and (b) is in (a). It is EE sectional drawing.
For example, in the suspension flexure substrate 1 shown in FIG. 6, the planar substantially ring-shaped relative position measuring structure 16 a constituted by the first conductor and the substantially planar planar relative shape constituted by the second conductor. A position measurement structure 16 b is formed on the same first insulating layer 31.

  With such a configuration, since the structure 16a and the structure 16b exist on the same plane without the second insulating layer 32, the overlapping state of the structure 16a and the structure 16b is determined by the second conductor. When detecting the reflected light from above, the overlapping state of the structural body 16a and the structural body 16b is more accurately detected without being affected by absorption, reflection, or scattering of the reflected light by the second insulating layer 32. be able to.

  Note that the above-described configuration can be similarly formed not only in the structures 16a and 16b illustrated in FIG. 5A but also in the structures 16a and 16b illustrated in FIGS. 5B to 5H. it can.

  Further, as shown in FIGS. 5I and 5J, the center coordinates of the structure 16a and the center coordinates of the structure 16b are designed to be the same coordinates, and the planar shape of the structure 16a is the same. When the outer shape has a predetermined amount larger than the planar shape of the structure 16b, the structure 16b is formed on the structure 16a without the second insulating layer 32 interposed therebetween. You can also.

FIG. 7 is an explanatory view showing another example of the fourth embodiment of the flexure substrate for suspension according to the present invention, (a) is a schematic plan view of the main part, and (b) is in (a). It is FF sectional drawing.
For example, in the flexure substrate 1 for suspension shown in FIG. 7, a substantially circular planar shape constituted by the second conductor on the substantially circular planar relative position measuring structure 16 a constituted by the first conductor. The relative position measuring structure 16b is formed without the second insulating layer 32 interposed therebetween.

  In such a configuration, since the structure 16a and the structure 16b overlap with each other without the second insulating layer 32, the overlapping state of the structure 16a and the structure 16b is reflected from above the second conductor. When detecting with light, the overlapping state of the structure 16a and the structure 16b can be detected more accurately without being affected by absorption, reflection or scattering of the reflected light by the second insulating layer 32. .

  In the first to fourth embodiments described above, for example, as shown in FIG. 8A, the cover layer 41 in the region where the structures 16a and 16b are formed may be removed.

  With such a configuration, for example, the relative position measurement structure 16a composed of the first conductor and the relative position measurement structure 16b composed of the second conductor are overlapped with each other. When the reflected light is detected from above the conductor, absorption, reflection or scattering of the reflected light by the cover layer 41 can be eliminated, so that it is easier to detect the overlapping state of the structures 16a and 16b by the reflected light. Because it becomes.

  8A is a region where the structure 16a and the structure 16b are formed by removing the cover layer 41 in the region where the structures 16a and 16b are formed in the configuration example in FIG. This shows a form in which the second insulating layer 32 is exposed.

In the first to fourth embodiments described above, for example, as shown in FIG. 8B, the metal support 21 in the region where the structures 16a and 16b are formed may be removed. .
This is because with such a configuration, it is possible to detect not only the reflected light but also the overlapping state of the structures 16a and 16b by transmitted light.

  In FIG. 8B, in the configuration example in FIG. 4, the metal support 21 in the region where the structures 16a and 16b are formed has openings 51, and the structures 16a and 16b are formed. The form which the 1st insulating layer 31 of the area | region which has exposed is exposed is shown.

  Next, other elements constituting the suspension flexure substrate according to the present invention will be described.

[Metal support]
The material of the metal support 21 is not particularly limited as long as it has desired conductivity and springiness, and examples thereof include stainless steel. The thickness of the metal support 21 is, for example, preferably in the range of 10 μm to 30 μm, and more preferably in the range of 15 μm to 25 μm.

[First insulating layer]
The first insulating layer 31 is an insulating layer formed on the surface of the metal support 21. The material for the first insulating layer 31 is not particularly limited as long as it has a desired insulating property, and examples thereof include polyimide (PI). The material of the first insulating layer 31 may be a photosensitive material or a non-photosensitive material. The thickness of the first insulating layer 31 is, for example, preferably in the range of 5 μm to 30 μm, and more preferably in the range of 5 μm to 10 μm.

[First conductor]
The first conductors 11, 12, and 13 are conductors formed on the first insulating layer 31. The material of the first conductors 11, 12, 13 is not particularly limited as long as it has desired conductivity, and examples thereof include copper (Cu).
As thickness of the 1st conductors 11, 12, and 13, it is preferable to exist in the range of 4 micrometers-18 micrometers, for example. If the thickness of the first conductors 11, 12, 13 is too small, it may not be possible to obtain the desired conductivity. If the thickness of the first conductors 11, 12, 13 is too large, the wiring circuit board This is because the rigidity may increase.

On the other hand, the line width of the first conductors 11, 12, 13 is preferably in the range of 10 μm to 300 μm, for example. If the line widths of the first conductors 11, 12, 13 are too small, there is a possibility that sufficient impedance reduction cannot be achieved. If the line widths of the first conductors 11, 12, 13 are too large, a printed circuit board. This is because there is a possibility that sufficient density cannot be increased.
The first conductors 11, 12, and 13 may have a wiring plating layer formed of nickel (Ni) or gold (Au) on the surface thereof.

[Second insulating layer]
The second insulating layer 32 is an insulating layer formed on the first conductors 11, 12, and 13. The material of the second insulating layer 32 is the same as that of the first insulating layer 31 described above. Moreover, it is preferable that the thickness of the 2nd insulating layer 32 formed on the 1st conductors 11, 12, and 13 exists in the range of 4 micrometers-18 micrometers, for example. If the thickness is too small, there is a possibility of deterioration of transmission characteristics and short-circuiting due to pinholes. If the thickness is too large, the thickness of the entire flexure substrate for suspension may be increased.

[Second conductor]
The second conductor 14 is a conductor formed on the second insulating layer 32. The material of the second conductor 14 is the same as that of the first conductors 11, 12, and 13 described above. The second conductor 14 may have a wiring plating layer formed of nickel (Ni) or gold (Au) on the surface thereof. The thickness of the second conductor layer is preferably in the range of 4 μm to 15 μm, for example.
The line width of the second conductor 14 is the same as that of the first conductors 11, 12, and 13 described above.

[Cover layer]
Examples of the material of the cover layer 41 include polyimide (PI). Further, the material of the cover layer 41 may be a photosensitive material or a non-photosensitive material. Note that the material of the cover layer 41 may be the same as or different from the first insulating layer 12 and the second insulating layer 15 described above. The thickness of the cover layer 41 is preferably in the range of 3 μm to 30 μm, for example.

[Manufacturing method of flexure substrate for suspension]
Next, a method for manufacturing a flexure substrate for suspension according to the present invention will be described.
The manufacturing method of the suspension flexure substrate according to the present invention is the same process as the process of forming the first wiring by processing the first conductor 13 of the relative position measuring structure 16a constituted by the first conductor. The relative position measurement structure 16b formed and formed by the second conductor is formed in the same step as the step of processing the second conductor 14 to form part of the second wiring. Is.

  Hereinafter, the manufacturing method of the flexure substrate for suspension according to the present invention will be described more specifically with reference to the drawings. However, in the method for manufacturing a flexure substrate for suspension according to the present invention, components other than the above-described structure for measuring the relative position, for example, the first wiring and the second wiring, the first insulating layer and the second insulating layer, and Since a conventionally known method can be used as a method for forming the cover layer or the like, detailed description thereof is omitted here.

  FIG. 9 is a schematic process diagram showing an example of a manufacturing method of the flexure substrate for suspension according to the present invention shown in FIG.

  First, as shown in FIG. 9A, the first insulating layer 31 is formed on the metal support 21, and the first conductor layer 13 </ b> A is formed on the first insulating layer 31.

Next, using a plate making technique such as photolithography, the formation of the structure 16a for measuring the relative position and the formation of the first conductor 13 constituting the first wiring are performed in the same process (FIG. 9B). ).
In addition to the formation of the structure 16a and the first conductor 13 constituting the first wiring, the first conductors 11 and 12 constituting a part of the second wiring are simultaneously formed in this step (see FIG. Not shown).
Here, since the structure 16a and the first conductor 13 are formed in the same process, the two are in the positional relationship as designed. Therefore, the position of the first wiring composed of the first conductor 13 can be guaranteed by detecting the position of the structure 16a.

  Next, a second insulating layer 32 is formed on the structure 16a, the first conductor 13, and the first conductors 11 and 12 (not shown) (FIG. 9C), and further, the second insulating layer. A resist pattern 61 for electrolytic plating is formed on 32 (FIG. 9D).

  Next, the formation of the structure 16b for measuring the relative position and the formation of the second conductor 14 constituting a part of the second wiring are performed in the same process by an electrolytic plating method (FIG. 9E). Since the structural body 16b and the second conductor 14 are formed in the same process, the positional relationship is as designed. Therefore, the position of the second wiring made of the second conductor 14 can be guaranteed by detecting the position of the structure 16b.

  Next, the resist pattern 61 is removed (FIG. 9 (f)), and thereafter, the cover layer 41 is formed (FIG. 9 (g)), the metal support 21 is opened, etc. A suspension flexure substrate is obtained.

  Next, an example of the manufacturing method of the flexure substrate for suspension according to the present invention shown in FIG. 6 will be described with reference to FIG.

  First, as shown in FIG. 10A, the first insulating layer 31 is formed on the metal support 21, and the first conductor layer 13 </ b> A is formed on the first insulating layer 31.

Next, using a plate making technique such as photolithography, the formation of the structure 16a for relative position measurement and the formation of the first conductor 13 constituting the first wiring are performed in the same process (FIG. 10B). ).
In addition to the formation of the structure 16a and the first conductor 13 constituting the first wiring, the first conductors 11 and 12 constituting a part of the second wiring are simultaneously formed in this step (see FIG. Not shown).
Here, since the structure 16a and the first conductor 13 are formed in the same process, the two are in the positional relationship as designed. Therefore, the position of the first wiring composed of the first conductor 13 can be guaranteed by detecting the position of the structure 16a.

  Next, the second insulating layer 32 is formed on the first conductor 13 and the first conductors 11 and 12 (not shown) (FIG. 10C). Here, the structure 16 a is exposed so as not to be covered with the second insulating layer 32.

  Next, a resist pattern 61 for electrolytic plating is formed on the first insulating layer 31, the structure 16a, and the second insulating layer 32 (FIG. 10 (d)), and relative position measurement is performed by electrolytic plating. The formation of the structure 16b and the formation of the second conductor 14 constituting a part of the second wiring are performed in the same process (FIG. 10E). Since the structural body 16b and the second conductor 14 are formed in the same process, the positional relationship is as designed. Therefore, the position of the second wiring made of the second conductor 14 can be guaranteed by detecting the position of the structure 16b.

  Next, the resist pattern 61 is removed (FIG. 10 (f)), and thereafter, the cover layer 41 is formed (FIG. 10 (g)), the metal support 21 is opened, etc. A suspension flexure substrate is obtained.

  Next, an example of the manufacturing method of the flexure substrate for suspension according to the present invention shown in FIG. 7 will be described with reference to FIG.

  First, as shown in FIG. 11A, the first insulating layer 31 is formed on the metal support 21, and the first conductor layer 13 </ b> A is formed on the first insulating layer 31.

Next, using a plate making technique such as photolithography, the formation of the structure 16a for relative position measurement and the formation of the first conductor 13 constituting the first wiring are performed in the same process (FIG. 11B). ).
In addition to the formation of the structure 16a and the first conductor 13 constituting the first wiring, the first conductors 11 and 12 constituting a part of the second wiring are simultaneously formed in this step (see FIG. Not shown).
Here, since the structure 16a and the first conductor 13 are formed in the same process, the two are in the positional relationship as designed. Therefore, the position of the first wiring composed of the first conductor 13 can be guaranteed by detecting the position of the structure 16a.

  Next, the second insulating layer 32 is formed on the first conductor 13 and the first conductors 11 and 12 (not shown) (FIG. 11C). Here, the structure 16 a is exposed so as not to be covered with the second insulating layer 32.

  Next, a resist pattern 61 for electrolytic plating is formed on the first insulating layer 31, the structure 16a, and the second insulating layer 32 (FIG. 11D), and the relative position measurement is performed by electrolytic plating. The formation of the structure 16b and the formation of the second conductor 14 constituting a part of the second wiring are performed in the same process (FIG. 11E). Since the structural body 16b and the second conductor 14 are formed in the same process, the positional relationship is as designed. Therefore, the position of the second wiring made of the second conductor 14 can be guaranteed by detecting the position of the structure 16b.

  Next, the resist pattern 61 is removed (FIG. 11 (f)). Thereafter, the cover layer 41 is formed (FIG. 11 (g)), the metal support 21 is opened, etc. A suspension flexure substrate is obtained.

  By using the manufacturing method as described above, in the present invention, the suspension flexure having the structure for measuring the relative position of the first wiring and the second wiring in the multilayer wiring without increasing the number of complicated steps. A substrate can be manufactured.

[Inspection method for flexure substrate for suspension]
Next, a method for inspecting a flexure substrate for suspension according to the present invention will be described.
The method for inspecting a flexure substrate for suspension according to the present invention optically measures the overlapping state of a relative position measurement structure 16a composed of a first conductor and a relative position measurement structure 16b composed of a second conductor. By detecting automatically, the relative position of the 1st wiring which consists of the 1st conductor 13, and the 2nd wiring which consists of the 2nd conductor 14 is ensured.

  By using such an inspection method, in the present invention, the relative positions of the first wiring and the second wiring can be guaranteed without using a special measuring machine.

  In the present invention, the cover layer 41 is not formed on the region where the position measurement structures 16a and 16b are formed, and the portions other than the portion where the position measurement structure 16b is formed. A cover layer 41 is formed on the two conductors, and the overlapping state of the relative position measuring structure 16a constituted by the first conductor and the relative position measuring structure 16b constituted by the second conductor is shown. The relative position of the first wiring made of the first conductor 13 and the second wiring made of the second conductor 14 may be guaranteed by detecting the reflected light from above the second conductor.

  By using such an inspection method, absorption, reflection, or scattering of the reflected light by the cover layer 41 can be eliminated, so that it is easier to detect the overlapping state of the structures 16a and 16b by the reflected light. It is.

    Further, in the present invention, an opening is formed in the metal support 21 so as to expose the first insulating layer 31 in the region where the structure bodies 16a and 16b for position measurement are formed, and is configured by the first conductor. And detecting the overlapping state of the relative position measurement structure 16a constituted by the second conductor and the relative position measurement structure 16b by the transmitted light, The relative position of the second wiring made of the second conductor 14 may be guaranteed.

  This is because by using such an inspection method, it is possible to detect the overlapping state of the structures 16a and 16b not only by reflected light but also by transmitted light.

[suspension]
Next, the suspension of the present invention will be described. The suspension of the present invention includes the above-described suspension substrate.

  The suspension of the present invention includes the above-described suspension flexure substrate 1 and a load beam provided on the surface of the suspension flexure substrate 1 opposite to the surface on which the gimbal portion is formed. As the load beam, the same load beam used for a general suspension can be used.

  According to the present invention, by using the above-described suspension flexure substrate, it is possible to obtain a suspension that achieves lower impedance.

[Suspension with head]
Next, the head suspension according to the present invention will be described. The suspension with a head of the present invention includes the above-described suspension and a magnetic head slider mounted on the suspension.
Since the suspension is the same as described above, description thereof is omitted here. Further, the magnetic head slider can be the same as the magnetic head slider used in a general suspension with a head.

  According to the present invention, by using the above-described suspension, a suspension with a head that achieves lower impedance can be obtained.

[Hard disk drive]
Next, the hard disk drive of the present invention will be described. The hard disk drive of the present invention includes the above-described suspension with a head.

  The hard disk drive of the present invention has at least a suspension with a head, and usually further includes a disk, a spindle motor, an arm, and a voice coil motor. Since the suspension with a head is the same as described above, description thereof is omitted here. As other members, the same members as those used in a general hard disk drive can be used.

  According to the present invention, a hard disk drive with higher functionality can be obtained by using the suspension with a head described above.

  The above has described the flexure substrate for suspension, the suspension, the suspension with head, the hard disk drive, and the manufacturing method and the inspection method of the flexure substrate for suspension according to the present invention, but 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.

DESCRIPTION OF SYMBOLS 1 ... Flexure board for suspensions 13A ... 1st conductor layer 11, 12, 13 ... 1st conductor 14A ... 2nd conductor layer 14 ... 2nd conductor 15 ... Connection part 16a, 16b ... Relative position measurement structure 21 ... Metal support 31 ... First insulating layer 32 ... Second insulating layer 41 ... Cover layer 51 ... Opening 61 ... Resist pattern DESCRIPTION OF SYMBOLS 100, 200 ... Suspension flexure board | substrate 102 ... Gimbal part 103, 103a, 103b ... Connection terminal part 104, 104a, 104b ... Read wiring 105 ... Write wiring 111 ... Read element 211, 212, 213 ... first conductor 214 ... second conductor 215 ... connection part 221 ... metal support 231 ... first insulating layer 232 ... second insulating layer 241, ..Cover layer

Claims (10)

A first conductor, a second insulating layer, and a second conductor are sequentially stacked at least partially on the first insulating layer formed on the metal support,
A first wiring made of the first conductor;
A second wiring comprising the first conductor and the second conductor and having a configuration in which the first conductor and the second conductor are connected through a connection portion formed in an opening provided in the second insulating layer; In the flexure substrate for suspension provided,
A pair of structures for measuring the relative position of the first wiring and the second wiring,
The first conductor that does not constitute the first wiring or the second wiring, and the second conductor that does not constitute the second wiring;
In plan view,
A relative position measuring structure formed on the first conductor;
A structure for measuring a relative position formed on the second conductor,
A flexure substrate for suspension, which has point-symmetric shapes having different sizes . The suspension flexure substrate according to claim 1, wherein the relative position measuring structure has a substantially ring shape, a substantially frame shape, a substantially cross shape, a substantially circular shape, or a substantially rectangular shape . Wherein on the second wiring made of the second conductor, flexible substrate for suspension according to claim 1 or claim 2, characterized in that the cover layer is formed. The structure for relative position measurement composed of the second conductor and the second insulating layer in the region where the structure for relative position measurement composed of the first conductor is formed are exposed. The suspension flexure substrate according to claim 3 , wherein a part of the cover layer is removed . An opening is formed in the metal support so that the first insulating layer is exposed in a region where the structure for measuring the relative position composed of the first conductor and the second conductor is formed. The suspension flexure substrate according to any one of claims 1 to 4 . A suspension comprising the flexure substrate for suspension according to any one of claims 1 to 5 . A suspension with a head comprising the suspension according to claim 6 and a magnetic head slider mounted on the suspension . A hard disk drive comprising the suspension with a head according to claim 7 . It is a manufacturing method of the flexure substrate for suspensions in any one of Claims 1-5,
The structure for measuring the relative position formed from the first conductor,
Forming in the same step as the step of forming the first wiring from the first conductor;
The relative position measuring structure formed from the second conductor,
A method of manufacturing a flexure substrate for suspension, wherein the second conductor is formed in the same step as the step of forming a part of the second wiring from the second conductor . A method for inspecting a flexure substrate for a suspension according to any one of claims 1 to 5,
By optically detecting the overlapping state of the relative position measurement structure formed from the first conductor and the relative position measurement structure formed from the second conductor,
A method for inspecting a flexure substrate for suspension, wherein a relative position between the first wiring and the second wiring is guaranteed .

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