JP2010097659A - Suspension substrate, suspension, suspension with head and hard disk drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a suspension substrate which has wiring disposed in a magnetic head slider mounting area and its vicinity, and has high electric stability for a magnetic head slider, grounding performance and adhesive strength. <P>SOLUTION: The suspension substrate includes a metal substrate 1, an insulating layer 2 formed on the metal substrate, a signal wiring 13 formed on the insulating layer, and further includes a gimbal section 11 having a magnetic head slider mounting area for mounting a magnetic head slider. The suspension substrate includes at least one of a wiring formed in the magnetic head slider mounting area and a wiring formed outside the mounting area and in a position where the magnetic head slider is brought into contact with the gimbal section by distortion of the gimbal section, and a ground terminal 4 for supporting the magnetic head slider and electrically connecting the grounding electrode part of the magnetic head slider and the metal substrate. The vertex of the ground terminal is higher than that of the wiring. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a suspension substrate used in a hard disk drive (HDD). More specifically, the present invention has a wiring (for example, highly functionalized wiring) in a magnetic head slider mounting region or in the vicinity thereof, and an electric circuit for the magnetic head slider. TECHNICAL FIELD The present invention relates to a suspension board having good mechanical stability, ground contact performance and adhesive strength.

  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. Accordingly, hard disk drives incorporated in personal computers (hereinafter simply referred to as HDDs) There is also a need to increase the capacity and speed of information transmission. In addition, a component called a magnetic head suspension that supports the magnetic head used in the HDD 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 is now integrated into a wiring integrated type (flexure).

  Recently, there has been an increase in demand for HDDs mounted on various small devices such as portable applications. For this reason, HDDs have become denser and magnetic heads have become smaller, and magnetic heads have become more sensitive. It is easily affected by static electricity. Therefore, there has been a problem that the characteristics of the small magnetic head element are changed by the electric charge accumulated in the slider, or in the worst case, it is destroyed.

  Further, as another problem, in order to improve the signal transmission speed and accuracy of the HDD, in recent years, there has been a tendency to use a higher frequency electric signal. However, as the frequency becomes higher, the noise of the transmitted electric signal becomes smaller. There was a problem of increasing.

  In order to solve these problems, a grounding means for performing electrical connection using a conductive resin between the magnetic head slider and the suspension has been used. However, there is a problem that static electricity cannot be sufficiently removed by connection using a conductive resin. Further, since the conductive resin usually does not have a sufficient adhesive force, there is a problem that the magnetic head slider and the suspension cannot be bonded with sufficient strength.

  On the other hand, Patent Document 1 discloses a head slider support having a spacer and a conductive pattern on a metal substrate. In this technique, grounding is ensured by arranging a conductive pattern in a shape along the spacer between the magnetic head slider and the metal substrate of the head slider support. Therefore, not a conductive adhesive having a weak adhesive force but a non-conductive adhesive having a strong adhesive force can be used, and durability can be improved. The spacer can be formed simultaneously with the formation of the insulating pattern of the head slider support. Similarly, the conductive pattern can be formed simultaneously with the formation of the wiring pattern of the head slider support. Therefore, the manufacturing process can be simplified.

JP 2000-215428 A

  As described above, when grounding the magnetic head slider and the metal substrate of the suspension, it is important to realize good grounding performance and adhesive strength. Conventionally, members arranged between the magnetic head slider and the metal substrate of the suspension have been limited to spacers and adhesives. This is because the area between the magnetic head slider and the suspension metal substrate is mainly an area for grounding, and it is not necessary to use other members. Furthermore, it is for preventing having a bad influence on grounding performance and adhesive strength by using another member.

  However, as a result of the diligent research conducted by the present inventors to further increase the functionality of the suspension, the design aims to increase the functionality in and around the magnetic head slider mounting area where the magnetic head slider is mounted. There is a need to arrange such wiring (high-performance wiring). In addition, in order to increase the functionality of the suspension substrate, it may be assumed that signal wiring is arranged in the magnetic head slider mounting region or in the vicinity thereof. However, the fact is that there is no knowledge about the electrical stability, grounding performance and adhesive strength of the suspension provided with such wiring.

  The present invention has been made in view of the above circumstances, and has wiring (for example, highly functionalized wiring) in the magnetic head slider mounting region and its vicinity, and has electrical stability and grounding performance with respect to the magnetic head slider. The main object of the present invention is to provide a suspension substrate having good adhesive strength.

  In order to achieve the above object, in the present invention, there is provided a suspension substrate comprising a metal substrate, an insulating layer formed on the metal substrate, and a signal wiring formed on the insulating layer. A gimbal portion having a magnetic head slider mounting area on which the magnetic head slider is mounted, wiring formed within the magnetic head slider mounting area, and outside the magnetic head slider mounting area; and , Having at least one of wirings formed at positions where the magnetic head slider comes into contact with the gimbal portion being bent, supporting the magnetic head slider, and grounding electrode portions of the magnetic head slider and the It has a ground terminal for electrically connecting a metal substrate, and the top of the ground terminal is higher than the top of the wiring. Providing a substrate for suspension according to claim.

  According to the present invention, since the top of the ground terminal is located higher than the top of the wiring (for example, highly functional wiring), it is possible to prevent contact between the magnetic head slider and the wiring when the magnetic head slider is mounted. . Therefore, it is possible to provide a suspension substrate having good electrical stability with respect to the magnetic head slider. Further, according to the present invention, since the ground terminal performs grounding of the magnetic head slider, sufficient grounding performance can be ensured. Therefore, not only a conductive adhesive but also various nonconductive materials having strong adhesive strength can be used. As a result, a suspension substrate having good grounding performance and adhesive strength for the magnetic head slider can be obtained.

  In the above invention, the wiring is preferably a highly functional wiring for the purpose of enhancing the functionality of the suspension substrate. This is because a suspension substrate with higher functionality can be obtained.

  In the said invention, it is preferable that the cover layer is formed so that the said wiring may be covered, and the top part of the said ground terminal exists in a position higher than the top part of the said cover layer formed on the said wiring. This is because a more practical suspension substrate can be obtained.

  In the said invention, it is preferable that the said ground terminal is directly formed from the surface of the said metal substrate. This is because the ground terminal has a simple structure and is easy to design.

  In the said invention, it is preferable that the said ground terminal is formed by the plating method. This is because the ground terminal can be easily formed.

  In another example of the invention, the ground terminal includes a lower portion of the ground terminal formed on the surface of the metal substrate, and a conductive layer in contact with the lower portion of the ground terminal and formed on the insulating layer. It is preferable to have a ground terminal intermediate portion and a ground terminal upper portion that contacts the ground terminal intermediate portion and contacts the ground electrode portion of the magnetic head slider. Compared with the case where the ground terminal is formed directly from the surface of the metal substrate, the height of the upper portion of the ground terminal can be designed low. Therefore, when forming the upper portion of the ground terminal by, for example, plating, the upper portion of the ground terminal can be formed with high accuracy and in a short time.

  In the said invention, it is preferable that the said ground terminal lower part and the said ground terminal upper part are formed by the plating method. This is because the lower portion of the ground terminal and the upper portion of the ground terminal can be easily formed.

  The present invention also provides a suspension including the above-described suspension substrate.

  According to the present invention, by using the above-described suspension substrate, it is possible to obtain a suspension with good electrical stability, grounding performance, and adhesive strength with respect to the magnetic head slider.

  According to the present invention, there is provided a suspension with a head comprising the above-described suspension and a magnetic head slider mounted on the magnetic head slider mounting region of the suspension.

  According to the present invention, by using the above-described suspension, a suspension with a head having excellent electrical stability, grounding performance, and adhesive strength with respect to the magnetic head slider can be obtained.

  The present invention also provides a hard disk drive including the suspension with a head described above.

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

  In the present invention, there is an effect that a suspension substrate having good electrical stability, grounding performance and adhesive strength with respect to the magnetic head slider can be obtained.

  Hereinafter, the suspension substrate, suspension, suspension with head, and hard disk drive of the present invention will be described in detail.

A. First, the suspension substrate of the present invention will be described. A suspension substrate according to the present invention is a suspension substrate having a metal substrate, an insulating layer formed on the metal substrate, and a signal wiring formed on the insulating layer, wherein the magnetic head slider includes A gimbal portion having a magnetic head slider mounting region to be mounted; wiring formed in the magnetic head slider mounting region; and outside the magnetic head slider mounting region; and the gimbal portion It has at least one of the wirings formed at the position where the magnetic head slider comes into contact by bending, supports the magnetic head slider, and electrically connects the grounding electrode portion of the magnetic head slider and the metal substrate. And the top of the ground terminal is higher than the top of the wiring. Than is.

  Next, the suspension substrate of the present invention will be described with reference to FIGS. FIG. 1 is a schematic plan view showing an example of the suspension substrate of the present invention. A suspension board 20 shown in FIG. 1 connects a gimbal part 11 formed at one tip part, a relay board connection part 12 formed at the other tip part, and the gimbal part 11 and the relay board connection part 12. And a signal wiring 13 to be used. Although not shown, the suspension substrate 20 generally has a basic structure in which a metal substrate made of SUS or the like, an insulating layer made of polyimide (PI) or the like, and a signal wiring made of copper or the like are laminated in this order. Have.

  FIG. 2 is a schematic plan view showing a gimbal portion of the suspension substrate. The gimbal portion 11 shown in FIG. 2 has a magnetic head slider mounting area 14 on which the magnetic head slider is mounted. Here, the “magnetic head slider mounting area” refers to an area of the gimbal portion that coincides with an area where the magnetic head slider is mounted in a plan view. In FIG. 2, the magnetic head slider mounting area 14 has a highly functional wiring 3 and a ground terminal 4. The highly functional wiring 3 will be described later in detail.

FIG. 3 is a cross-sectional view taken along the line AA of FIG. 3 includes a metal substrate 1, an insulating layer 2 formed on the metal substrate 1, a highly functional wiring 3 and signal wiring 13 formed on the insulating layer 2, and an insulating layer 2. And a ground terminal 4 in contact with the metal substrate 1 exposed from the opening. Further, in the substrate for suspension, top T _a ground terminal 4 is at a position higher than the top portion T _b of the high performance interconnect 3.

  FIG. 4 is a schematic cross-sectional view showing an example of a suspension substrate on which a magnetic head slider is mounted. In FIG. 4, a magnetic head slider 23 having a ground electrode portion 21 and a wiring electrode portion 22 is mounted. The ground electrode portion 21 of the magnetic head slider 23 and the metal substrate 1 of the suspension substrate 20 are connected to the ground. It is electrically connected via the terminal 4. Further, the magnetic head slider 23 and the suspension substrate 20 are bonded by an adhesive portion 24 made of, for example, a non-conductive adhesive. On the other hand, the wiring electrode portion 22 of the magnetic head slider 23 and the signal wiring 13 of the suspension substrate 20 are electrically connected via a wiring connection portion 25 made of solder, gold balls, or the like. Further, as shown in FIG. 4, a cover layer 15 may be provided on the highly functional wiring 3 and the signal wiring 13 as necessary. In the present invention, when the highly functionalized wiring 3 has the cover layer 15, the top of the highly functionalized wiring 3 may be higher than the top of the cover layer 15 formed on the highly functionalized wiring 3. preferable.

  As described above, according to the present invention, since the top of the ground terminal is located higher than the top of the wiring (for example, highly functional wiring), when the magnetic head slider is mounted, the magnetic head slider and the wiring Contact can be prevented. Therefore, it is possible to provide a suspension substrate having good electrical stability with respect to the magnetic head slider. Furthermore, since it is possible to prevent the magnetic head slider and the wiring from coming into contact with each other, it is possible to prevent the generation of minute foreign matters caused by rubbing between the magnetic head slider and the wiring (or the cover layer formed on the wiring). . Further, when the magnetic head slider is mounted on the suspension substrate of the present invention, the top of the ground terminal is at a higher position than the top of the wiring, so that the magnetic head slider floats with respect to the wiring. As a result, the degree of freedom in wiring design is improved and higher functionality can be achieved.

  Further, according to the present invention, since the ground terminal performs grounding of the magnetic head slider, sufficient grounding performance can be ensured. Therefore, not only a conductive adhesive but also various nonconductive materials having strong adhesive strength can be used. As a result, a suspension substrate having good grounding performance and adhesive strength for the magnetic head slider can be obtained. In addition, according to the present invention, since the ground terminal supports and grounds the magnetic head slider, space saving can be achieved.

  The head slider support disclosed in Patent Document 1 described above has a conductive pattern between the magnetic head slider and the metal substrate of the suspension. This conductive pattern functions as a wiring. is not.

  Here, the suspension substrate of the present invention has a great feature in the gimbal portion. The gimbal portion is usually formed at the tip of the suspension substrate. Hereinafter, the suspension substrate of the present invention will be described focusing on the configuration of the gimbal portion.

1. First, the ground terminal in the present invention will be described. The ground terminal in the present invention supports the magnetic head slider and electrically connects the ground electrode portion of the magnetic head slider and the metal substrate of the suspension substrate. Further, in the present invention, as shown in FIG. 3 described above, for example, the top portion T _a ground terminal 4 is at a position higher than the top portion T _b of the high performance interconnect 3.

  In the present invention, the top of the ground terminal is preferably higher than the top of the wiring (for example, highly functional wiring) by 10 μm or more, and more preferably within the range of 20 μm to 50 μm. If the height difference between the two is too small, the magnetic head slider and the wiring may come into contact with each other. If the height difference between the two is too large, the height of the ground terminal will be relatively high. This is because the mechanical strength may be lowered. For example, when the cover layer which covers wiring is formed, it is preferable that the top part of a ground terminal is high in said range with respect to the top part of the cover layer formed on wiring.

  Next, the material of the ground terminal in the present invention will be described. The material of the ground terminal in the present invention is usually a conductive metal material. Especially, in this invention, it is preferable that the material of a ground terminal is a metal material excellent in adhesiveness with a metal substrate. As such a metal material, for example, silver (Ag), gold (Au), copper (Cu), nickel (Ni) and the like can be used, among which silver (Ag) and nickel (Ni) are preferable, and nickel is particularly preferable. (Ni) is preferred. This is because it is excellent in conductivity and corrosion resistance and is inexpensive.

  In particular, when the ground terminal is formed by electrolytic plating using nickel, examples of the electrolytic Ni plating bath used include a watt bath and a sulfamic acid bath. In addition, glossiness and a film | membrane stress can be adjusted by using an additive for these plating baths suitably.

  Next, the structure of the ground terminal in the present invention will be described. The structure of the ground terminal in the present invention is particularly limited as long as it can support the magnetic head slider and can electrically connect the ground electrode portion of the magnetic head slider and the metal substrate of the suspension substrate. is not. As an example of the structure of the ground terminal in the present invention, one in which the ground terminal is formed directly from the surface of the metal substrate can be mentioned.

  As such a ground terminal, specifically, as shown in FIG. 3, a ground terminal 4 formed directly from the surface of the metal substrate 1 can be exemplified. Here, the ground terminal 4 is formed so as to fill the opening of the insulating layer 2. Although the shape of the opening part of the insulating layer 2 is not specifically limited, For example, circular and rectangular shape can be mentioned. The size of the opening of the insulating layer 2 is preferably in the range of, for example, 30 μm to 300 μm, more preferably in the range of 30 μm to 200 μm, and particularly preferably in the range of 50 μm to 100 μm. As an example of a method of forming a ground terminal having such a structure, an insulating layer opening is first formed, and then a plating method is performed on a metal substrate exposed from the opening.

  As another example of the structure of the ground terminal in the present invention, the ground terminal is in contact with the lower part of the ground terminal formed on the surface of the metal substrate, and the conductive part formed on the insulating layer in contact with the lower part of the ground terminal. Examples include a ground terminal intermediate portion made of layers and a ground terminal upper portion in contact with the ground terminal intermediate portion and in contact with the ground electrode portion of the magnetic head slider.

  Specifically, as such a ground terminal, as shown in FIG. 5A, a ground terminal lower part 4a formed on the surface of the metal substrate 1, a ground terminal lower part 4a, and an insulating layer. 2 having a ground terminal intermediate portion 4b formed of a conductive layer formed on 2 and a ground terminal upper portion 4c that contacts the ground terminal intermediate portion 4b and contacts a ground electrode portion (not shown) of the magnetic head slider. The terminal 4 can be mentioned. Here, the ground terminal upper portion 4 c is formed so as to fill the opening of the cover layer 15, and the ground terminal lower portion 4 a is formed so as to fill the opening of the insulating layer 2. Since the shapes and sizes of the openings of the cover layer and the insulating layer are the same as the contents of the insulating layer described with reference to FIG. 3 described above, description thereof is omitted here. The ground terminal lower part 4a and the ground terminal upper part 4c can be formed by, for example, a plating method. The details of the method for forming the ground terminal having such a structure will be described later in “6. Method for manufacturing suspension substrate”.

  FIG. 5B is a diagram in which a magnetic head slider is mounted on the gimbal portion shown in FIG. In this case, similarly to FIG. 4 described above, the magnetic head slider 23 and the suspension substrate 20 are connected by the bonding portion 24 and the wiring connection portion 25. FIG. 6 is a plan view of FIG. Specifically, FIG. 5A is a cross-sectional view taken along the line AA in FIG. In FIG. 6, the cover layer is not shown for convenience.

  In addition, the ground terminals shown in FIGS. 5A and 5B have the following advantages compared to the ground terminals shown in FIGS. 3 and 4 described above. First, since the upper part of the ground terminal is formed not on the metal substrate but on the conductive layer, the height of the upper part of the ground terminal can be designed low. Therefore, when forming the upper portion of the ground terminal by, for example, plating, the upper portion of the ground terminal can be formed with high accuracy and in a short time. Second, since the upper portion of the ground terminal and the lower portion of the ground terminal are separated from each other, the formation position of the lower portion of the ground terminal can be arbitrarily designed. Thereby, for example, the lower portion of the ground terminal can be disposed outside the magnetic head slider mounting area, and the degree of freedom in designing the wiring can be improved. Further, as shown in FIG. 6, by connecting the ground terminal intermediate part 4b, the ground terminal upper part 4c, that is, the contact part with the magnetic head slider is plated only by forming one ground terminal lower part 4a. The space loss due to the formation of the ground terminal lower portion 4a can be minimized. In addition, the conductive layer used in the middle part of the grant terminal and the lower part of the ground terminal can be formed simultaneously when forming the signal wiring and the ground terminal part of the suspension board, thereby simplifying the manufacturing process of the ground terminal. Can be

  Next, the shape of the ground terminal in the present invention will be described. The shape of the ground terminal in the present invention is not particularly limited as long as it can support the magnetic head slider, but is preferably a shape that can support the magnetic head slider in a balanced manner. The shape of the ground terminal (upper part of the ground terminal) in the present invention will be described with reference to FIG. FIG. 7 is a schematic plan view illustrating the shape of the ground terminal in the present invention. For convenience, the description of the highly functional wiring is omitted.

  FIG. 7A shows an aspect in which a plurality of columnar ground terminals 4 are arranged. In this case, it is preferable that the columnar ground terminals 4 are arranged in a target manner in the magnetic head slider mounting region 14. Moreover, it is preferable that the columnar ground terminals 4 have a uniform height (the same applies to FIGS. 7B to 7E described later). The number of columnar ground terminals 4 arranged in the magnetic head slider mounting region 14 is not particularly limited, but is preferably 3 or more. This is because the magnetic head slider can be supported more stably. Examples of the planar shape of the columnar ground terminal 4 include a circular shape, a semicircular shape, an elliptical shape, and a polygonal shape. For example, when the planar shape of the columnar ground terminal 4 is circular, the diameter is preferably in the range of 30 μm to 200 μm, and more preferably in the range of 50 μm to 100 μm.

  FIG. 7B and FIG. 7C are embodiments in which the frame-like ground terminal 4 is disposed so as to surround the central portion of the magnetic head slider mounting region 14 in plan view. In this case, it is possible to suppress the adhesive used when mounting the magnetic head slider from flowing out. In the present invention, as shown in FIG. 7 (b), the frame of the ground terminal 4 may have a polygonal shape composed of only a straight line in plan view. As shown in FIG. 7 (c), The frame of the ground terminal 4 may have a shape constituted by a straight line and a curve in plan view. The width of the ground terminal 4 is, for example, preferably in the range of 30 μm to 200 μm, and more preferably in the range of 50 μm to 100 μm (the same applies to FIGS. 7D to 7E described later).

  FIG. 7D and FIG. 7E are embodiments in which the ground terminal 4 is disposed so as to surround the central portion of the magnetic head slider mounting region 14 in a partially open state in plan view. In this case, it is possible to increase the degree of freedom in designing the wiring while suppressing the adhesive used when mounting the magnetic head slider from flowing out. In the present invention, as shown in FIG. 7 (d), the ground terminal 4 may be U-shaped in plan view, and as shown in FIG. 7 (e), the ground terminal 4 is planar. In view, it may have a shape in which a plurality of rod-like ground terminals 4 are arranged.

  The resistance value of the ground terminal in the present invention is, for example, preferably 5Ω or less, more preferably 1Ω or less, and particularly preferably in the range of 0.10Ω to 0.25Ω.

2. The wiring formed in the magnetic head slider mounting area and the vicinity thereof The suspension substrate of the present invention is the wiring formed in the magnetic head slider mounting area, the outside of the magnetic head slider mounting area, and It has at least one of the wirings formed at the position where the magnetic head slider comes into contact with the gimbal portion that is bent. Specific examples of such wiring include highly functional wiring for the purpose of enhancing the functionality of the suspension substrate. Further, such wiring may be signal wiring described later. Here, the following description will be focused on highly functional wiring.

  The highly functional wiring in the present invention is formed in the magnetic head slider mounting area, outside the magnetic head slider mounting area, and the magnetic head slider comes into contact with the gimbal portion when it is bent. Examples include those formed at the positions and those corresponding to both.

  The highly functional wiring in the present invention is a general term for wiring for the purpose of enhancing the functionality of the suspension substrate. Here, the highly functional wiring will be described. In order to record an enormous amount of information faster and more compactly (smaller area), the HDD continues to evolve toward higher speed and higher density. In order to realize these, the magnetic head slider is not only made smaller and more sensitive, but also, if necessary, functional elements are added around the gimbal to provide high-precision position control, high-frequency signal support, noise support, etc. It is necessary to improve functionality by collectively naming them all. Functional elements refer to, for example, chip parts such as amplifiers, resistors and capacitors, various actuators represented by piezo elements, various sensors, and special parts such as semiconductor lasers corresponding to the new recording method. The highly functional wiring in this case refers to wiring added along with the addition of functional elements around the magnetic head slider (around the gimbal portion). Four wires are sufficient for the magnetic head slider to perform original writing and reading, but the number of wires has increased to 5 to 8 with the above-mentioned enhancement of functionality, and further increases are expected in the future. The In order to carry out the increased wiring only at the magnetic head slider peripheral portion as in the past, extreme thinning is required, leading to an increase in cost and a decrease in productivity, which is not desirable. In order to solve such a problem, by increasing the mounting height of the magnetic head slider and arranging the wiring under the magnetic head slider, it is possible to easily route the wiring increased due to the higher functionality.

  In addition, the highly functional wiring in the present invention is added not only with the wiring added along with the addition of the functional elements described above, but also with high functionality due to the miniaturization and high sensitivity of the magnetic head slider itself. It also includes wiring. Details of this case will be described later with reference to FIG.

  In the present invention, the high-performance wiring is formed in the magnetic head slider mounting area, and the high-performance wiring is outside the magnetic head slider mounting area and the gimbal portion is There are cases where the magnetic head slider is formed at a position where it contacts by bending, and both cases. Here, the magnetic head slider mounting area in the present invention refers to the area of the gimbal portion that coincides with the area where the magnetic head slider is mounted in plan view, as described with reference to FIG. As a specific example in the case where the highly functionalized wiring is formed in the magnetic head slider mounting region, as shown in FIGS. 8A and 8B, the gimbal portion 11 includes the magnetic head slider mounting region 14. A case where the highly functional wiring 3 is formed in the region can be given.

  On the other hand, the high-performance wiring may be formed outside the magnetic head slider mounting area and at a position where the magnetic head slider comes into contact by bending the gimbal portion. Since the gimbal part is bent by a metal substrate with spring properties, there is a possibility that the magnetic head slider and the high-performance wiring may come into contact even when the high-performance wiring is outside the magnetic head slider mounting area. There is. Therefore, it is necessary to make the top of the ground terminal higher than the top of such highly functional wiring. Here, although the position where the gimbal part comes into contact depends on the shape and mounting height of the magnetic head slider, the shape of the gimbal part, etc., for example, the magnetic head slider mounting area and the wiring outside the area The distance is 100 μm or less, preferably 50 μm or less. Further, as a specific example in such a case, as shown in FIG. 8C, the gimbal portion 11 is out of the magnetic head slider mounting region 14 and the gimbal portion 11 is bent to cause magnetism. A case where the highly functional wiring 3 is formed at a position where the head slider comes into contact can be cited.

  FIG. 8D shows a case where the ground terminal intermediate portion 4b is connected to a ground wiring (high performance wiring) 3 formed for another purpose. In this case, the ground terminal intermediate portion 4b itself can be positioned as a highly functional wiring. It may be preferable to connect the ground wiring and the middle portion of the ground terminal in view of common ground potential and stabilization of signal potential. Here, grounding the magnetic head slider is also a high function in terms of noise countermeasures, and it can be said that the magnetic head slider itself has a high function by miniaturization and high sensitivity. Therefore, when a plurality of ground terminal intermediate portions are shared (a loop is formed in FIG. 8D), it can be positioned as a highly functional wiring.

  In particular, in the present invention, it is preferable that at least a part of the wiring is in the area of the magnetic head slider mounting area. This is because the effects of the present invention are easily exhibited.

  Examples of the material for the highly functionalized wiring include copper (Cu). Further, the thickness of the highly functionalized wiring is not particularly limited as long as the desired electrical conductivity can be exhibited. For example, the thickness is in the range of 6 μm to 18 μm, and in particular in the range of 8 μm to 12 μm. Preferably there is. The highly functional wiring may be formed at the same time as the signal wiring described later. In that case, the thickness of the highly functional wiring and the signal wiring is usually the same. Further, the line width of the highly functionalized wiring is not particularly limited as long as the desired electrical conductivity can be exhibited. For example, it is in the range of 10 μm to 100 μm, and in particular, 15 μm to 50 μm. It is preferable to be within the range.

  In the present invention, a protective plating layer may be formed on the surface of the highly functionalized wiring. By forming the protective plating layer, signal wiring that is resistant to corrosion can be obtained. Examples of the material for the protective plating layer include nickel (Ni) and gold (Au). Moreover, the film thickness of a protective plating layer is 5 micrometers or less, for example, and it is preferable to exist in the range of 0.1 micrometer-2 micrometers especially.

  In the present invention, a cover layer may be formed so as to cover the highly functional wiring. By forming the cover layer, an electric signal can be transmitted more reliably. Note that the cover layer is usually formed so as to have an insulating property and not to prevent transmission of an electric signal. As the material of the cover layer, the same material as the material of the cover layer used for signal wiring of a general suspension board can be used. The thickness of the cover layer is, for example, in the range of 3 μm to 30 μm.

3. Insulating layer The insulating layer in this invention is formed on the metal substrate mentioned later. Further, as shown in FIG. 4 described above, the insulating layer 2 formed on the gimbal portion 11 preferably has an opening for forming the bonding portion 24. This is because the magnetic head slider can be firmly bonded. Further, as shown in FIG. 3 described above, the insulating layer 2 formed in the gimbal portion may have an opening for forming the ground terminal 4.

  Examples of the material for the insulating layer include polyimide (PI). In addition, the thickness of the insulating layer is not particularly limited as long as desired insulating properties can be exhibited, but it is within a range of 3 μm to 30 μm, for example.

4). Metal Substrate The metal substrate in the present invention usually has conductivity and moderate springiness. Also, as shown in FIG. 4 described above, the metal substrate 1 formed on the gimbal portion 11 is normally electrically connected to the magnetic head slider 23 via the ground terminal 4. Examples of the material for the metal substrate include SUS.

  The thickness of the metal substrate is not particularly limited as long as a desired spring characteristic can be exhibited. The thickness varies depending on the material of the metal substrate, for example, within a range of 10 μm to 30 μm. In particular, it is preferably within a range of 15 μm to 25 μm.

  In the present invention, the metal substrate preferably has a conductive layer on the surface side where the ground terminal is formed. This is because by providing the conductive layer, conduction by the ground terminal becomes more efficient. Specific examples of the material for the conductive layer include copper (Cu). Such a conductive layer can be formed by, for example, a plating method.

5). Signal Wiring The signal wiring in the present invention is formed on the insulating layer described above. As shown in FIG. 4 described above, the signal wiring 13 reaching the gimbal portion 11 is usually electrically connected to the magnetic head slider 23 via the wiring connection portion 25. As a result, data written to the disk and data read from the disk can be transmitted as electrical signals. Examples of the material for the signal wiring include copper (Cu).

  The thickness of the signal wiring is not particularly limited as long as the desired conductivity can be exhibited. For example, the thickness of the signal wiring is in the range of 4 μm to 18 μm, and in particular in the range of 8 μm to 12 μm. preferable. The line width of the signal wiring is not particularly limited as long as the desired electrical conductivity can be exhibited. For example, it is in the range of 10 μm to 100 μm, and in particular in the range of 15 μm to 50 μm. Preferably there is.

  In the present invention, a protective plating layer is preferably formed on the surface of the signal wiring. Further, a cover layer may be formed so as to cover the signal wiring. The protective plating layer and the cover layer are the same as those described in “2. Wiring formed in or near the magnetic head slider mounting region” described above, so description thereof is omitted here.

6). Next, a method for manufacturing a suspension substrate according to the present invention will be described. The manufacturing method of the suspension substrate of the present invention is not particularly limited as long as it is a method capable of obtaining the above-described suspension substrate. Further, as described above, the suspension substrate of the present invention has a great feature in the gimbal portion. Therefore, here, the method for manufacturing the suspension substrate according to the present invention will be described focusing on the formation of the gimbal portion.

  FIG. 9 is a schematic cross-sectional view showing an example of a method for manufacturing a suspension substrate according to the present invention. More specifically, a method for forming a gimbal portion having the same structure as that shown in FIG. 3 will be described. In FIG. 9, first, a laminate in which the metal substrate 1a, the insulating layer 2a, and the conductive layer 3a are laminated in this order is prepared (FIG. 9A). Next, a dry film resist is laminated on the surface of the conductive layer 3a, and a resist pattern is formed by performing exposure and development. Next, the conductive layer 3a exposed from the resist pattern is etched, and the resist pattern is peeled off after the etching, thereby forming the signal wiring 13 and the highly functional wiring 3 (FIG. 9B). At this time, a similar resist pattern may be formed using a dry film resist, and the metal substrate 1a may be etched simultaneously.

  Next, a cover layer 15 is formed by applying a photosensitive cover layer forming material (for example, photosensitive polyimide) so as to cover the signal wiring 13 and the highly functional wiring 3 and performing exposure and development ( FIG. 9 (c)). At this time, the cover layer 15 may be formed by applying a non-photosensitive cover layer forming material in a pattern. Moreover, you may provide a cover layer in at least one part of the highly functional wiring 3 as needed. Next, a dry film resist is laminated so as to cover the signal wiring 13, the highly functional wiring 3 and the cover layer 15, and a resist pattern is formed by performing exposure and development. Next, the insulating layer 2a exposed from the resist pattern is etched, and the resist pattern is peeled off after the etching, thereby forming the patterned insulating layer 2 (FIG. 9D).

  Next, a dry film resist is laminated so as to cover the signal wiring 13, the highly functional wiring 3, and the cover layer 15, and exposure and development are performed, whereby a resist having an opening corresponding to the opening of the insulating layer 2. Form a pattern. Next, the ground terminal 4 is formed by performing plating on the metal substrate 1a exposed from the opening of the resist pattern (FIG. 9E). Next, a dry film resist is laminated on the surface of the metal substrate 1a, and a resist pattern is formed by performing exposure and development. Next, the metal substrate 1a exposed from the resist pattern is etched, and the resist pattern is peeled off after the etching, whereby the patterned metal substrate 1 is formed. Thereby, the suspension substrate 20 can be obtained (FIG. 9F).

  Next, a method of forming a ground terminal having a structure different from that of the above-described suspension board ground terminal will be described. FIG. 10 is a schematic cross-sectional view showing another example of the method for manufacturing a suspension substrate according to the present invention. More specifically, a method for forming a gimbal portion having the same structure as that shown in FIG. In FIG. 10, first, a laminate in which the metal substrate 1a, the insulating layer 2a, and the conductive layer 3a are laminated in this order is prepared (FIG. 10A). Next, a dry film resist is laminated on the surface of the conductive layer 3a, and a resist pattern is formed by performing exposure and development. Next, the conductive layer 3a exposed from the resist pattern is etched, and the resist pattern is peeled off after the etching, thereby forming the signal wiring 13, the ground terminal intermediate portion 4b, and the highly functional wiring 3 (FIG. 10B). ).

  Next, a photosensitive cover layer forming material (for example, photosensitive polyimide) is applied so as to cover the signal wiring 13, the ground terminal intermediate portion 4 b and the highly functional wiring 3, and exposure and development are performed. The layer 15 is formed (FIG. 10C). At this time, a cover layer may be provided on at least a part of the highly functionalized wiring 3 as necessary. Next, a dry film resist is laminated so as to cover the signal wiring 13, the ground terminal intermediate portion 4 b, the highly functional wiring 3, and the cover layer 15, and a resist pattern is formed by performing exposure and development. Next, the insulating layer 2a exposed from the resist pattern is etched, and the resist pattern is peeled off after the etching, thereby forming the patterned insulating layer 2 (FIG. 10D).

  Next, a dry film resist is laminated so as to cover the signal wiring 13, the ground terminal intermediate portion 4 b, the highly functional wiring 3, and the cover layer 15, and exposure and development are performed, thereby corresponding to the opening of the insulating layer 2. A resist pattern having an opening to be formed is formed. Next, the metal substrate 1a exposed from the opening portion of the resist pattern is plated to form the ground terminal lower portion 4a, and further to the ground terminal intermediate portion 4b exposed from the cover layer 15, By performing the plating method, the ground terminal upper portion 4c is formed (FIG. 10E). Next, a dry film resist is laminated on the surface of the metal substrate 1a, and a resist pattern is formed by performing exposure and development. Next, the metal substrate 1a exposed from the resist pattern is etched, and the resist pattern is peeled off after the etching, whereby the patterned metal substrate 1 is formed. Thereby, the suspension substrate 20 can be obtained (FIG. 10F).

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

  FIG. 11 is a schematic plan view showing an example of the suspension of the present invention. A suspension 40 shown in FIG. 11 has the above-described suspension substrate 20 and a load beam 30 provided on the surface of the suspension substrate 20 opposite to the surface on which the magnetic head slider mounting region 14 is formed. Is.

  According to the present invention, by using the above-described suspension substrate, it is possible to obtain a suspension with good electrical stability, grounding performance, and adhesive strength with respect to the magnetic head slider.

  The suspension of the present invention has at least a suspension substrate, and usually further has a load beam. The suspension substrate is the same as the content described in “A. Suspension substrate”, and therefore, the description thereof is omitted here. The load beam can be the same as the load beam used for a general suspension.

C. Next, the suspension with a head according to the present invention will be described. The suspension with a head according to the present invention includes the above-described suspension and a magnetic head slider mounted on the magnetic head slider mounting region of the suspension.

  FIG. 12 is a schematic plan view showing an example of the suspension with a head of the present invention. A suspension 50 with a head shown in FIG. 12 has the above-described suspension 40 and a magnetic head slider 23 mounted on the magnetic head slider mounting region 14 of the suspension 40.

  According to the present invention, by using the above-described suspension, a suspension with a head having excellent electrical stability, grounding performance, and adhesive strength with respect to the magnetic head slider can be obtained.

  The suspension with a head of the present invention has at least a suspension and a magnetic head slider. The suspension is the same as that described in “B. Suspension” above, and is not described here. Further, the magnetic head slider can be the same as the magnetic head slider used in a general suspension with a head.

  Further, as described in “A. Suspension substrate”, the suspension and the magnetic head slider can be bonded using an adhesive. The adhesive used in the present invention may be a conductive adhesive or a non-conductive adhesive, but is preferably a non-conductive adhesive. This is because a non-conductive adhesive generally has high adhesive strength and can firmly bond a magnetic head slider. Further, since the suspension of the present invention has the above-described ground terminal, it is not necessary to positively use a conductive adhesive. The adhesive used in the present invention may be a thermosetting adhesive.

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

  FIG. 13 is a schematic plan view showing the hard disk drive of the present invention. A hard disk drive 60 shown in FIG. 13 is connected to the above-described suspension 50 with a head, a disk 61 on which the head suspension 50 writes and reads data, a spindle motor 62 that rotates the disk 61, and the suspension 50 with a head. The arm 63, the arm 63 and the voice coil motor 64 for moving the magnetic head slider of the suspension 50 with head, and the case 65 for sealing the above-described members are provided.

  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 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. The suspension with a head is the same as the contents described in the above “C. Suspension with a head”, and therefore description thereof is omitted here. As other members, the same members as those used in a general hard disk drive can be used.

  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]
This embodiment will be described with reference to FIG. 9 described above. In the present example, the above-described ground terminal having a shape in plan view shown in FIG. 2 was produced. First, SUS304 (metal substrate 1a) having a thickness of 20 μm, a polyimide layer (insulating layer 2a) having a thickness of 10 μm, and a Cu layer (conductive layer 3a) made of electrolytic copper having a thickness of 9 m are stacked in this order. A body was prepared (FIG. 9A). Next, a dry film resist was laminated on the surface of the Cu layer, and exposure and development were performed to form a resist pattern. Next, the Cu layer exposed from the resist pattern was chemically etched, and the resist pattern was peeled off after the etching. Thus, the signal wiring 13 and the highly functional wiring 3 were obtained (FIG. 9B).

  Next, a photosensitive polyimide was applied so as to cover the signal wiring 13 and the highly functional wiring 3, and exposure and development were performed to form a cover layer 15 (FIG. 9C). Next, a dry film resist was laminated so as to cover the signal wiring 13, the highly functional wiring 3, and the cover layer 15, and a resist pattern was formed by performing exposure and development. Next, the insulating layer 2a exposed from the resist pattern was chemically etched, and the resist pattern was peeled off after the etching. As a result, a patterned insulating layer 2 was obtained (FIG. 9D). The shape of the opening of the insulating layer 2 provided for forming the ground terminal was a columnar shape, and its diameter was 100 μm.

  Next, a dry film resist is laminated so as to cover the signal wiring 13, the highly functional wiring 3, and the cover layer 15, and exposure and development are performed, whereby a resist having an opening corresponding to the opening of the insulating layer 2. A pattern was formed. Next, the ground terminal 4 was obtained by performing nickel electroplating on SUS exposed from the opening of the resist pattern (FIG. 9E). The top of the obtained ground terminal 4 was 30 μm higher than the top of the highly functionalized wiring 3. The cross-sectional view of the ground terminal 4 in a plan view was a circle having a diameter of 160 μm. Next, a dry film resist was laminated on the surface of SUS, and a resist pattern was formed by performing exposure and development. Next, SUS exposed from the resist pattern was chemically etched, and the resist pattern was peeled off after etching to form a patterned SUS. Thereby, the gimbal part 11 in which the top part of the ground terminal 4 was higher than the top part of the highly functionalized wiring 3 was obtained (FIG. 9F).

  Although not shown in FIG. 9, a non-conductive thermosetting adhesive is then applied to the opening of the polyimide layer (insulating layer 2) where the SUS (metal substrate 1) is exposed using a dispenser. did. Next, a magnetic head slider was placed on the ground terminals 4 and the adhesive was heated. Thereby, the magnetic head slider was mounted. Finally, the signal wiring 13 and the wiring connection portion of the magnetic head slider were connected using solder. As a result, a suspension substrate on which the magnetic head slider was mounted was obtained. Here, when the resistance of the ground terminal 4 was measured, it was 0.15Ω, indicating good grounding performance. Further, since a non-conductive adhesive was used, the magnetic head slider and the suspension substrate showed good adhesive strength.

[Example 2]
This embodiment will be described with reference to FIG. In the present example, the above-described ground terminal having the shape shown in FIG. 6 was produced. First, SUS304 (metal substrate 1a) having a thickness of 20 μm, a polyimide layer (insulating layer 2a) having a thickness of 10 μm, and a Cu layer (conductive layer 3a) made of electrolytic copper having a thickness of 9 m are stacked in this order. A body was prepared (FIG. 10A). Next, a dry film resist was laminated on the surface of the Cu layer, and exposure and development were performed to form a resist pattern. Next, the Cu layer exposed from the resist pattern was chemically etched, and the resist pattern was peeled off after the etching. Thus, the signal wiring 13, the ground terminal intermediate portion 4b, and the highly functional wiring 3 were obtained (FIG. 10B).

  Next, a photosensitive polyimide is applied so as to cover the signal wiring 13, the ground terminal intermediate portion 4b, and the highly functional wiring 3, and exposure and development are performed to form the cover layer 15 (FIG. 10C). )). Next, a dry film resist was laminated so as to cover the signal wiring 13, the ground terminal intermediate portion 4 b, the highly functional wiring 3, and the cover layer 15, and exposure and development were performed to form a resist pattern. Next, the insulating layer 2a exposed from the resist pattern was chemically etched, and the resist pattern was peeled off after the etching. Thereby, a patterned insulating layer 2 was obtained (FIG. 10D). The shape of the opening of the insulating layer 2 provided to form the lower portion of the ground terminal was a columnar shape, and its diameter was 100 μm.

  Next, a dry film resist is laminated so as to cover the signal wiring 13, the ground terminal intermediate portion 4 b, the highly functional wiring 3, and the cover layer 15, and exposure and development are performed, thereby corresponding to the opening of the insulating layer 2. A resist pattern having openings to be formed was formed. Next, nickel electrolytic plating was performed on SUS exposed from the opening of the resist pattern, thereby obtaining a ground terminal lower portion 4a. Similarly, the ground terminal upper part 4c was obtained by performing nickel electroplating on the ground terminal intermediate part 4b exposed from the opening (columnar shape, diameter of 100 μm) of the cover layer 15 (FIG. 10E). . The top part of the obtained ground terminal upper part 4 c was 30 μm higher than the top part of the highly functionalized wiring 3. The cross section in plan view of the ground terminal upper portion 4c was a circle having a diameter of 160 μm. Next, a dry film resist was laminated on the surface of SUS, and a resist pattern was formed by performing exposure and development. Next, SUS exposed from the resist pattern was chemically etched, and the resist pattern was peeled off after etching to form a patterned SUS. Thereby, the gimbal part 11 in which the top part of the ground terminal 4 was higher than the top part of the highly functionalized wiring 3 was obtained (FIG. 10F).

  Although not shown in FIG. 10, a non-conductive thermosetting adhesive is then applied to the opening of the polyimide layer (insulating layer 2) where the SUS (metal substrate 1) is exposed using a dispenser. did. Next, a magnetic head slider was placed on the ground terminals 4 and the adhesive was heated. Thereby, the magnetic head slider was mounted. Finally, the signal wiring 13 and the wiring connection portion of the magnetic head slider were connected using solder. As a result, a suspension substrate on which the magnetic head slider was mounted was obtained. Here, when the resistance of the ground terminal 4 was measured, it was 0.2Ω, which showed good grounding performance. Further, since a non-conductive adhesive was used, the magnetic head slider and the suspension substrate showed good adhesive strength.

It is a schematic plan view which shows an example of the board | substrate for suspensions of this invention. It is a schematic plan view which shows the gimbal part of the board | substrate for suspensions. It is AA sectional drawing of FIG. It is a schematic sectional drawing which shows an example of the board | substrate for suspension with which the magnetic head slider was mounted. It is a schematic sectional drawing explaining the gimbal part of the board | substrate for suspensions of this invention. It is a schematic plan view explaining the gimbal part of the suspension substrate of the present invention. It is a schematic plan view which illustrates the shape of the ground terminal in this invention. It is a schematic plan view explaining the highly functional wiring in this invention. It is a schematic sectional drawing which shows an example of the manufacturing method of the board | substrate for suspensions of this invention. It is a schematic sectional drawing which shows the other example of the manufacturing method of the board | substrate for suspensions of this invention. It is a schematic plan view which shows an example of the suspension of this invention. It is a schematic plan view which shows an example of the suspension with a head of this invention. 1 is a schematic plan view showing a hard disk drive of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a ... Metal substrate 2, 2a ... Insulating layer 3 ... High functional wiring 3a ... Conductive layer 4 ... Ground terminal 4a ... Ground terminal lower part 4b ... Ground terminal intermediate part 4c ... Ground terminal upper part 11 ... Gimbal part 12 ... Relay board Connection part 13 ... Signal wiring 14 ... Magnetic head slider mounting area 15 ... Cover layer 20 ... Suspension substrate 21 ... Grounding electrode part 22 ... Wiring electrode part 23 ... Magnetic head slider 24 ... Adhesive part 25 ... Wiring connection part 30 ... Load beam 40 ... Suspension 50 ... Suspension with head 60 ... Hard disk drive 61 ... Disk 62 ... Spindle motor 63 ... Arm 64 ... Voice coil motor 65 ... Case

Claims (10)

A suspension substrate having a metal substrate, an insulating layer formed on the metal substrate, and a signal wiring formed on the insulating layer,
Comprising a gimbal portion having a magnetic head slider mounting area on which the magnetic head slider is mounted;
Wiring formed in the magnetic head slider mounting area, and outside the magnetic head slider mounting area, and formed at a position where the magnetic head slider comes into contact by bending the gimbal portion. Having at least one of the wiring
A ground terminal for supporting the magnetic head slider and electrically connecting the grounding electrode portion of the magnetic head slider and the metal substrate;
The suspension substrate, wherein the top of the ground terminal is located higher than the top of the wiring.   2. The suspension substrate according to claim 1, wherein the wiring is a highly functional wiring for the purpose of enhancing the functionality of the suspension substrate.   The cover layer is formed so as to cover the wiring, and the top of the ground terminal is located higher than the top of the cover layer formed on the wiring. 2. The suspension substrate according to 2.   The suspension substrate according to any one of claims 1 to 3, wherein the ground terminal is formed directly from the surface of the metal substrate.   The suspension substrate according to claim 4, wherein the ground terminal is formed by a plating method.   The ground terminal has a ground terminal lower part formed on the surface of the metal substrate, a ground terminal intermediate part made of a conductive layer in contact with the ground terminal lower part and formed on the insulating layer, and the ground terminal. The suspension substrate according to any one of claims 1 to 3, further comprising a ground terminal upper portion that contacts an intermediate portion and contacts a ground electrode portion of the magnetic head slider.   The suspension substrate according to claim 6, wherein the lower portion of the ground terminal and the upper portion of the ground terminal are formed by a plating method.   A suspension comprising the suspension substrate according to any one of claims 1 to 7.   9. A suspension with a head, comprising: the suspension according to claim 8; and a magnetic head slider mounted on the magnetic head slider mounting region of the suspension.   A hard disk drive comprising the suspension with a head according to claim 9.

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