JP5151650B2 - Suspension board, suspension, suspension with head and hard disk - Google Patents

Description

  The present invention provides a grounding means that can be used for a hard disk drive (HDD) and can sufficiently prevent electrostatic breakdown and suppress noise even when the wiring is formed with a high density and a narrow pitch. The present invention relates to a suspension substrate.

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

  On the other hand, Patent Document 1 proposes that the ground wiring connected to the slider is electrically connected using a conductive resin on a metal substrate. According to such a method, it is not necessary to use an adhesive having a low adhesive force such as a conductive resin for bonding the slider and the metal substrate, and an adhesive having a strong adhesive force can be used. Since the wiring for wiring and the metal substrate are connected using a conductive resin, there is a problem that static electricity cannot be sufficiently removed.

In Patent Document 2, a metal pad is formed on the surface of an insulating layer stacked on a metal substrate to prevent electrostatic breakdown and suppress noise, and the metal substrate is exposed to the insulating layer and the metal pad. There has been proposed a grounding means in which a ground terminal for connecting the metal substrate and the metal pad is formed in the through hole formed as described above. According to such a grounding means, the grounding wiring connected to the slider can be connected to the metal pad to prevent electrostatic damage of the slider, and the slider and the metal substrate can be sufficiently strong. Can be glued. Further, by installing the metal pad in the vicinity of the wiring, it is possible to suppress noise generated on the suspension substrate and to stabilize the signal passing through the wiring.
However, since the grounding means disclosed in Patent Document 2 requires a large installation area for the metal pad, the downsizing of the installation space is required due to the downsizing of the magnetic head accompanying the recent increase in the density of HDDs. There is a problem that it may be difficult to install the suspension board on the suspension substrate.

JP 2004-164813 A JP 2006-202359 A

  The present invention has been made in view of the above problems, and can sufficiently prevent electrostatic breakdown and suppress noise even when a high-density wiring having a narrow pitch is formed. The main object is to provide a suspension substrate having a grounding means.

  In order to achieve the above object, the present invention is formed directly on a metal substrate, an insulating layer formed on the metal substrate, a signal wiring formed on the insulating layer, and the metal substrate. A suspension substrate having a ground terminal is provided.

  According to the present invention, since the ground terminal is directly formed on the metal substrate, the degree of freedom of the installation position of the ground terminal can be increased. Therefore, the ground terminal can be easily formed even when the signal wiring is formed with a high density and a narrow pitch.

  In the present invention, the ground terminal may be formed so as not to be in contact with the insulating layer, the insulating layer is formed so as to have a ground terminal opening, and A ground terminal may be formed in the ground terminal opening so as to be in contact with the insulating layer.

  In the present invention, the thickness of the ground terminal is preferably larger than the thickness of the insulating layer. Since the thickness of the ground terminal is greater than the thickness of the upper air insulating layer, it is possible to facilitate connection with a component such as a slider mounted on the suspension substrate of the present invention. It is. In addition, noise suppression can be efficiently achieved.

In the present invention, the ground terminal can be formed at a position where it can be connected to the magnetic head slider at the tip.
Since the ground terminal is formed at a position where it can be connected to the magnetic head slider at the tip, it is not necessary to form a grounding wiring, so the yield due to poor connection with the grounding wiring is reduced. Decline can be prevented. Furthermore, since a bridge or the like is not necessary, when used in a hard disk drive or the like, it is possible to stably read data via the slider.

  In the present invention, the ground terminal is placed in a slider installation position, which is a region where the magnetic head slider is mounted, and the parallelism of the magnetic head slider to the metal substrate can be maintained. be able to. The ground terminal is placed in a slider installation position, which is a region where the magnetic head slider is mounted, and can maintain parallelism of the magnetic head slider to the metal substrate. This is because when the suspension substrate of the invention is used in a hard disk drive, the accuracy of data reading and writing can be increased.

  In the present invention, the ground terminal may be formed between the signal wirings. This is because, when the ground terminal is formed between the signal wirings, noise can be reduced.

  The present invention provides a suspension including the suspension substrate.

  According to the present invention, since the suspension substrate is included, electrostatic breakdown and noise can be reduced.

  The present invention provides a suspension with a head comprising the suspension and a magnetic head slider mounted on the suspension.

  According to the present invention, since the suspension is included, electrostatic breakdown and noise can be reduced.

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

  According to the present invention, since the suspension with the head is included, the electrostatic breakdown and noise can be reduced. As a result, the data reliability and the like can be improved.

  The present invention provides a suspension substrate having a grounding means that can sufficiently prevent electrostatic breakdown and suppress noise even when a high-density wiring having a narrow pitch is formed. There is an effect that can be.

The present invention relates to a suspension board, a suspension using the same, a suspension with a head, and a hard disk drive.
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. The suspension substrate according to the present invention includes a metal substrate, an insulating layer formed on the metal substrate, a signal wiring formed on the insulating layer, and a ground terminal directly formed on the metal substrate. An aspect in which the ground terminal is not in contact with the insulating layer (first aspect), the insulating layer is formed to have a ground terminal opening, and The ground terminal can be divided into two modes: a mode (second mode) in which the ground terminal is formed in contact with the insulating layer in the ground terminal opening. Hereinafter, the suspension substrate of the present invention will be described separately for each embodiment.
Here, the fact that the ground terminal is directly formed on the metal substrate means that a grounding wiring connected to the ground terminal as formed in a conventional suspension substrate is not formed. It means that the ground terminal is formed independently.

1. First Aspect First, a first aspect of the suspension substrate of the present invention will be described. The suspension substrate according to this aspect is an aspect in which the ground terminal is not in contact with the insulating layer in the suspension substrate described above.

Such a suspension substrate of this embodiment will be described with reference to the drawings. FIG. 1 is a plan view showing an example of the suspension substrate of the present embodiment, and FIG. 2 is a cross-sectional view taken along the line AA of FIG. As illustrated in FIGS. 1 and 2, the suspension substrate 10 of this embodiment includes a metal substrate 1, an insulating layer 2 formed on the metal substrate 1, and a signal substrate formed on the insulating layer 2. The wiring 3 has a ground terminal 4 directly formed on the metal substrate 1.
Here, the suspension substrate 10 of this embodiment does not include a grounding wiring that is connected to the ground terminal 4, and is formed so that the ground terminal 4 does not contact the insulating layer 2.

  Conventionally, as illustrated in FIG. 24 which is a plan view illustrated in FIG. 23 and a cross-sectional view taken along line B-B in FIG. 23, the metal substrate 101 is formed on the metal substrate 101, and the ground terminal opening 105 is formed. A grounding wiring 106 and a signal wiring 103 which are formed on the insulating layer 102 and have an opening surrounding the ground terminal opening 105, and the ground terminal opening 105. The suspension substrate 100 is formed by filling the ground terminal metal with the metal substrate 101 and the ground terminal 104 connected to the ground wiring 106. In such a conventional suspension board, the grounding wiring is formed so as to surround the periphery of the opening for the ground terminal, so that the installation area of the grounding wiring becomes large. In addition, there is a problem that it may be difficult to use the suspension head for a use that requires a smaller installation space due to the downsizing of the magnetic head accompanying the recent increase in the density of the HDD. It was.

  On the other hand, according to this aspect, since the ground terminal is directly formed on the metal substrate, it is not necessary to form a grounding wiring to be connected to the ground terminal. There is no need to consider the space to do. For this reason, it is possible to increase the degree of freedom of the installation position of the ground terminal, and the ground terminal can be easily formed even when the signal wiring having a high density and a narrow pitch is formed. can do. In addition, since it is not necessary to consider the connection stability between the ground terminal and the grounding wiring, it is possible to prevent a decrease in yield due to poor connection with the grounding wiring.

  Further, since the ground terminal is not in contact with the insulating layer, the outer diameter can be reduced. That is, if it is in contact with a conventional insulating layer, a photoresist such as a dry film having an opening at the location where the ground terminal is formed is formed on the insulating layer, and a ground terminal opening is formed in the insulating layer. After forming, the photoresist is removed. Next, after forming a photoresist having an opening surrounding the opening of the ground terminal opening, the ground terminal metal is filled into the ground terminal opening to form the ground terminal. On the other hand, in this embodiment, a photoresist such as a dry film having an opening is formed directly on the metal substrate at a location where the ground terminal is formed, and the opening of the photoresist is filled with the metal for the ground terminal. Thus, the ground terminal is directly formed on the metal substrate. Thus, the outer diameter of the opening of the photoresist directly formed on the metal substrate is smaller than the outer diameter of the opening of the photoresist having an opening surrounding the opening of the conventional ground terminal opening. Therefore, the outer diameter of the ground terminal used in this embodiment may be smaller than the outer diameter of the ground terminal formed on the above-described conventional suspension substrate and in contact with the insulating layer. it can.

  Further, since the insulating layer is not in contact, the ground terminal can be easily formed at a location where the insulating layer is not normally formed and the metal substrate is exposed as in the slider installation position.

  In addition, signal wiring and grounding wiring are generally plated on the surface with gold or the like, but this plating method is usually connected to a ground terminal for cost reduction. The signal wiring and the ground wiring are connected by a connection wiring, and then plating is collectively formed on the surface using the signal wiring and the ground wiring as a power feeding layer. For this reason, when the grounding wiring is formed, it is necessary to consider the installation position of the ground terminal in consideration of the formation positions of the connection wiring and the grounding wiring. On the other hand, in this aspect, since the grounding wiring to be connected to the ground terminal is not formed, it is not necessary to consider the formation of the connection wiring, and the degree of freedom of the installation position of the ground terminal is large. It can be. For this reason, for example, as illustrated in FIG. 3, the metal substrate 1, the insulating layer 2 formed on the metal substrate 1, and the signal wiring 3 formed on the insulating layer 2, A suspension substrate in which an independent ground terminal 4 is formed between the signal wiring 3 and the signal wiring 3 can be easily formed.

  In addition, since it is not necessary to form a connection wiring between the grounding wiring and the signal wiring, it is possible to eliminate the formation of a bridge. Here, the bridge is a portion where a connection wiring for connecting the ground wiring and the signal wiring is formed. Conventionally, since the suspension board is relatively large and has a high degree of freedom in wiring design, for example, the ground wiring is separated from the ground terminal formation position where the ground terminal needs to be formed. It was possible to extend to the position and form a bridge. However, in a suspension substrate in which signal wiring and the like having a high density and a narrow pitch are formed, it is often difficult to extend the ground wiring to a position away from the ground terminal formation position. In that case, the bridge is required to be formed around the ground terminal formation position. When such a bridge is formed at the tip portion on which a slider for reading and writing data to and from the disk is mounted among the suspension substrates, the suspension substrate is difficult to adjust spring characteristics and the like. There is a risk that it may be difficult to read and write data through the slider while stably floating on the hard disk. On the other hand, in this aspect, since it is not necessary to form the grounding wiring, it is not necessary to form the connection wiring, and the formation of a bridge can be made unnecessary. It is possible to easily adjust the spring characteristics and the like. The bridge is a portion where a connection wiring for connecting the ground wiring and the signal wiring is formed, and more specifically, an insulating layer where the connection wiring is formed.

  The suspension substrate of this embodiment has at least a metal substrate, an insulating layer, signal wiring, and a ground terminal. Hereinafter, each configuration of the suspension substrate according to this aspect will be described.

(1) Ground terminal The ground terminal used in this embodiment is directly formed on a metal substrate described later, and is not in contact with an insulating layer described later.
Here, the ground terminal is directly formed on the metal substrate, as described above, the ground wiring connected to the ground terminal as formed in the conventional suspension substrate is formed. This means that the ground terminal is formed alone.
Note that the grounding wiring connected to the ground terminal includes not only the case where it is in direct contact with the ground terminal but also the case where it has an electrical connection. In other words, in this embodiment, not only the grounding wire that is in direct contact with the ground terminal, but also the grounding wire that is electrically connected through another layer made of a conductive material is not formed. is there.

The term “not in contact with the insulating layer” means that the ground terminal is surrounded by the opening from which the metal substrate is exposed, that is, there is a gap between the ground terminal and the insulating layer. is there.
Here, the gap between the ground terminal and the insulating layer is preferably within a range of 100 μm or less, more preferably within a range of 50 μm or less, and particularly preferably 30 μm or less. . By being in the above range, the ground terminal does not contact the insulating layer, and the installation area of the ground terminal is determined by the opening size of the resist shape for plating. In addition, the opening size of the insulating layer can be further reduced by narrowing the gap between the ground terminal and the insulating layer.
In addition, the lower limit of the gap between the ground terminal and the insulating layer may be as long as the ground terminal does not contact the insulating layer, but from the viewpoint of stably forming the gap between the ground terminal and the insulating layer, The lower limit of the gap is 10 μm.

  Since the ground terminal used in this embodiment is formed directly on the metal substrate and does not come into contact with an insulating layer described later, the outer diameter of the ground terminal can be reduced. In addition, the ground terminal can be easily formed at a location where the metal substrate is exposed without forming an insulating layer as in the slider installation position.

The ground terminal metal used to form the ground terminal used in this embodiment is not particularly limited as long as it is a conductive metal, but it may be a metal having excellent adhesion to a metal substrate described later. preferable. Specifically, silver (Ag), gold (Au), copper (Cu), nickel (Ni) and the like can be used, and among them, silver (Ag) and nickel (Ni) can be preferably used. Nickel (Ni) can be preferably used. This is because it is highly conductive and inexpensive. Moreover, it is because it is a material excellent in corrosion resistance.
These materials can be identified by XPS (X-ray Photoelectron Spectroscopy).

  In addition, when nickel is used as the metal for the ground terminal and the ground terminal is formed by an electrolytic plating method as shown in the manufacturing method of this embodiment described later, the ground terminal is formed in a desired shape as the electrolytic Ni plating solution. However, a Watt bath, a sulfamic acid bath, or the like can be used. Moreover, it is possible to adjust glossiness and film | membrane stress by adding an additive to a plating bath suitably.

  The shape of the ground terminal used in this aspect in plan view is not particularly limited as long as it can prevent electrostatic breakdown and remove noise, depending on the use of the suspension substrate of this aspect. It can be set appropriately. For example, a semicircular shape, a circular shape, an elliptical shape, an arbitrary polygonal shape such as a quadrangular shape or a pentagonal shape, a comb shape, a cross shape, a rod shape, and the like can be given.

The cross-sectional shape of the ground terminal used in this embodiment may be any shape as long as it is formed directly on the metal substrate described later and is not in contact with the insulating layer described later. be able to.
In this aspect, for example, the ground terminal is provided with a photoresist such as a dry film in which an opening is formed only at a location where the ground terminal is formed, as shown in the manufacturing method of the present aspect described later. When it is formed by plating in the part, it is usually a quadrangle as illustrated in FIG.

In addition, the formation position of the ground terminal used in this embodiment is not particularly limited as long as desired electrostatic breakdown prevention and noise suppression can be achieved. Specifically, as illustrated in FIG. 1 already described, the magnetic head slider may be provided at the tip of the suspension substrate. In FIG. 1, when the slider is mounted at the slider installation position 20, the ground terminal 4 is formed at a position where it can be connected to the slider. A signal wiring 3 extended to a position where the slider is connected is formed. Thus, when the magnetic head slider is installed, the ground terminal can be connected to the ground terminal of the magnetic head slider. For this reason, a grounding wiring for connecting to the grounding terminal of the magnetic head slider is not necessary, and a decrease in yield due to a poor connection between the grounding wiring and the ground terminal can be prevented. Further, since a bridge or the like is not necessary, when used in a hard disk drive or the like, it is possible to stably perform data reading or the like via the slider.
Further, as illustrated in FIG. 4, the ground terminal 4 may be formed so as to surround the slider installation position 20. Usually, since the suspension substrate and the slider are bonded using an adhesive, the ground terminal is formed so as to surround the slider installation position where the suspension substrate and the slider are bonded. This is because it is possible to prevent the adhesive from flowing out.

Further, as illustrated in FIG. 3, the suspension substrate may be provided in a portion other than the tip portion. In FIG. 3, the ground terminal 4 is formed between the signal wiring 3 and the signal wiring 3. This is because the noise can be reduced in this case.
Further, when the signal line is provided between the signal lines and is not connected to the magnetic head slider, the ground terminal is preferably formed along the signal line. This is because the noise removal effect can be improved.

  Here, the main function of the ground terminal when formed at the tip of the suspension substrate and between the signal wirings other than the tip of the suspension substrate and not connected to the magnetic head slider is noise. It is suppression. Accordingly, the ground terminals formed at such positions are used as noise suppression ground terminals or noise suppression inter-wiring ground terminals, respectively.

Further, it may be provided in a slider installation position where the magnetic head slider is installed at the tip of the suspension substrate.
Generally, static electricity is removed from the magnetic head slider through a conductive adhesive used for bonding the magnetic head slider. However, such an adhesive has a problem that the connection resistance is high and static electricity cannot be sufficiently removed.
On the other hand, since the ground terminal in this embodiment is made of a metal material, the connection resistance can be low. For this reason, the contact with the magnetic head slider can sufficiently release the static electricity stored in the magnetic head slider and can effectively prevent electrostatic breakdown.
Further, since the conductive adhesive has a relatively low hardness, it is easily deformed by the pressure when the magnetic head slider is mounted. For this reason, it has been difficult to stably support the magnetic head slider with the adhesive.
On the other hand, the ground terminal in this embodiment is a metal material and has a higher hardness than an adhesive or the like. For this reason, it can be made difficult to receive deformation due to pressure or the like when the magnetic head slider is mounted. Therefore, the magnetic head slider can be stably supported.

  Here, the formation position in the slider installation position may be a position where the ground terminal can be in contact with the magnetic head slider, but is a position where the magnetic head slider can be supported in a balanced manner. It is preferable. When the ground terminal is formed at such a position, the ground terminal can suppress the movement of the center of gravity of the magnetic head slider due to pressure applied when the magnetic head slider is mounted. That is, the ground terminal can maintain the parallelism of the magnetic head slider to the metal substrate. As a result, when the suspension substrate of this aspect is used in a hard disk drive, the hard disk drive can be made to have high data reading and writing accuracy. In this embodiment, the magnetic head slider can be fixed by using an adhesive in the slider installation position excluding the ground terminal.

As a position where such a magnetic head slider can be supported in a well-balanced manner, specifically, as shown in FIG. 5, a plurality of formation regions having a small area can be mentioned. Moreover, as illustrated in FIGS. 6A to 6B and FIGS. 7A to 7B, the slider may be formed so as to surround the center of the slider installation position. As shown in FIG. 5 described above, when there are a plurality of formation regions, that is, when a plurality of columnar ground terminals are formed, the number of formation is preferably 3 or more. . This is because the mounted magnetic head slider can be made more excellent in parallelism.
In this embodiment, as shown in FIGS. 6 (a) to 6 (b) and FIGS. 7 (a) to 7 (b), the slider is formed so as to surround the central portion. It is preferable that This is because it is possible to prevent the adhesive from flowing out to adhere the magnetic head slider.
Further, as illustrated in FIG. 8, the ground terminal may be integrally formed in the slider installation position and at a position connectable to the grounding terminal of the magnetic head slider. It is formed independently at the position. The thickness required for the ground terminal is usually different at the position where the slider is installed and at the position where it can be connected to the grounding terminal of the magnetic head slider. Because it becomes a thing.
5 to 8 are the same as those in FIG.

  Here, the main function of the ground terminal in the case where the suspension terminal is formed in the slider installation position of the suspension substrate is to remove static electricity. Therefore, the ground terminal formed in the slider installation position is used as a static electricity removing ground terminal.

In this aspect, it can be suitably formed at any of the above-mentioned formation positions, but in particular, it is preferably used at the tip of the suspension substrate on which the magnetic head slider is mounted. The slider mounting position on which the slider is mounted is usually because the metal substrate is exposed, and therefore the ground terminal can be easily formed because the ground terminal is not in contact with the insulating layer. It is.
In addition, in this aspect, the said formation position may be single and may contain 2 or more types. More specifically, the two or more types include, specifically, the tip portion and the slider installation position, between the tip portion and the signal wiring other than the tip portion, and within the slider installation position and the signal wiring other than the tip portion. It may be formed between. Further, it may be formed in the tip portion, in the slider installation position, and between signal wires other than the tip portion.

The thickness of the ground terminal used in this embodiment is preferably larger than the thickness of the insulating layer described later, and in particular, the thickness of the ground terminal is larger than the thickness of the insulating layer, and the insulating layer and the signal wiring described later are combined. The thickness is preferably the same as or smaller than the thickness, and is preferably the same as the combined thickness of the insulating layer and the signal wiring described later. Since the thickness of the ground terminal is larger than the thickness of the insulating layer, it is possible to easily connect a component such as a slider mounted on the suspension substrate of the present invention. is there. In addition, noise suppression can be efficiently achieved.
Further, the component mounted on the suspension substrate according to this aspect is larger than the thickness of the insulating layer and is equal to or smaller than the combined thickness of the insulating layer and the signal wiring described later. This is because problems such as contact can be prevented.
Furthermore, since the thickness of the ground terminal is the same as the combined thickness of the insulating layer and the signal wiring, that is, the surface of the ground terminal is the same height as the surface of the signal wiring, a slider or the like This is because the connection with the components mounted on the suspension substrate of the present invention can be made easier.

Further, when the ground terminal is formed in the slider installation position, the thickness of the ground terminal can be in contact with the magnetic head slider mounted on the slider installation position. It is preferable. This is because static electricity can be removed.
In this aspect, it is particularly preferable that the thickness in the slider installation position is uniform. This is because the magnetic head slider can be stably supported when the magnetic head slider is mounted. As a result, the ground terminal can maintain the parallelism of the magnetic head slider to the metal substrate.

In this aspect, when the ground terminal is formed in the slider installation position, it is formed with a uniform thickness at a position where the magnetic head slider as described above can be supported in a balanced manner. It is preferable that it is a thing.
This is because the ground terminal can more stably maintain the parallelism of the magnetic head slider to the metal substrate. As a result, when the suspension substrate of this aspect is used in a hard disk drive, the hard disk drive has a magnetic head slider mounted on the suspension substrate and a disk arranged in parallel. Moreover, the parallelism can be stably maintained. Therefore, the hard disk drive can have high data reading and writing accuracy.

The maximum width of the ground terminal used in this embodiment is not particularly limited as long as it can prevent electrostatic breakdown and remove noise, but the ground terminal is circular or rectangular. In this case, it is preferably within a range of 30 μm to 200 μm, and more preferably within a range of 50 μm to 100 μm. This is because, within the above range, even if the signal wiring with a narrow pitch is formed by increasing the density, it can be easily installed. Moreover, in this aspect, since the ground terminal can be reduced in size, the effect of the suspension substrate of the present aspect can be further exhibited by being in the above range.
In the case where the ground terminal is formed in a line shape, the line width is preferably within the range of the maximum width.

  The resistance value of the ground terminal is not particularly limited as long as it can prevent electrostatic breakdown and suppress noise. For example, it is preferably 5Ω or less, and more preferably 1Ω or less. It is particularly preferable that it is in the range of 0.10Ω to 0.25Ω.

(2) Signal wiring The signal wiring used in this embodiment is formed on an insulating layer to be described later. When the suspension substrate of this embodiment is used in an HDD, it is written on the disk via a slider. Data to be read or read from the disk is transmitted as an electrical signal.

  Examples of the material for the signal wiring used in this embodiment include copper (Cu).

  The thickness of the signal wiring used in this embodiment is not particularly limited as long as desired conductivity can be exhibited, but it is usually preferably in the range of 6 μm to 18 μm, and more preferably 8 μm. It is preferable to be within the range of -12 μm. This is because, if it is within the above range, the suspension substrate of the present invention can be prevented from becoming an obstacle when components such as a slider are mounted.

  The line width of the signal wiring used in this embodiment is not particularly limited as long as it can exhibit desired conductivity, but is preferably in the range of 10 μm to 100 μm. However, it is preferably in the range of 15 μm to 50 μm. This is because, by being in the above range, the signal wiring can be stably formed even when the pitch is narrowed by increasing the density.

  The pitch width of the signal wiring used in this embodiment is preferably in the range of 60 μm to 200 μm at the narrowest portion, and more preferably in the range of 60 μm to 100 μm. The ground terminal can be easily formed even when a high-density signal wiring having a narrow pitch is formed. For this reason, it is because the suspension board | substrate of this aspect can exhibit the effect more because it is the said range.

In general, the signal wiring used in this embodiment preferably has a protective plating layer formed of nickel (Ni) or gold (Au) on the surface thereof. This is because the signal wiring can be made resistant to corrosion.
Further, the thickness of the protective plating layer is not limited as long as the corrosion resistance can be ensured, but is preferably 5 μm or less, and more preferably in the range of 1 μm to 2 μm.
Further, the signal wiring may be partially covered with a cover lay having better insulation reliability than the protective plating layer.

(3) Insulating layer The insulating layer used for this aspect is formed on the metal substrate mentioned later.

  Examples of the material for the insulating layer include polyimide (PI).

  The thickness of the insulating layer is not particularly limited as long as a desired insulating property can be exhibited, but is usually about 5 μm to 30 μm.

(4) Metal substrate The metal substrate used in this embodiment has electrical conductivity and is used for suspension applications, and therefore usually has an appropriate spring property.

  Examples of the material of the metal substrate include SUS.

  In this aspect, it is preferable that the metal substrate 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). The conductive layer can be formed by, for example, a plating method.

  The thickness of the metal substrate is not particularly limited as long as the desired spring characteristics can be exhibited, and varies depending on the material of the metal substrate, but is usually in the range of 10 μm to 30 μm. Among these, it is preferable that it is in the range of 15 μm to 25 μm.

(5) Suspension substrate The suspension substrate of this aspect may have a cover lay (CL) on the insulating layer as necessary. Further, such a coverlay may be formed also on the ground terminal, but the ground terminal is for electrostatic removal of components such as a slider mounted on the suspension substrate. In the case of having a connection portion with a component such as the slider, it is usually formed to have an opening on a connection portion with the component such as the slider of the ground terminal. Although it does not specifically limit as thickness of the said coverlay, Usually, it is about 5 micrometers-about 30 micrometers. The material of the cover lay is not particularly limited, and the same material as the cover lay used for a general flexible substrate or the like can be used.

The method for manufacturing the suspension substrate according to this aspect is not particularly limited as long as each component of the suspension substrate can be accurately arranged at a desired position. For example, FIG. As shown in FIG. 2, the metal substrate 1, the insulating layer forming layer 2 ′ made of the material constituting the insulating layer, and the signal wiring forming layer made of the material constituting the signal wiring are formed on the metal substrate 1. 3 ′ is formed. Next, a photoresist 11 such as a dry film is provided on both surfaces of the laminate, and patterned into a predetermined shape (FIG. 9B). Thereafter, the signal wiring forming layer 3 ′ is patterned by etching, and the photoresist 11 is peeled off to form the signal wiring 3 (FIG. 9C). Thereafter, a photoresist 11 such as a dry film is provided and patterned into a predetermined shape (FIG. 9D), and then the insulating layer forming layer 2 ′ is patterned by etching (FIG. 9E). The insulating layer 2 is formed by removing the resist 11 (FIG. 9F).
Subsequently, as shown in FIG. 10A, a photoresist 11 such as a dry film is provided and patterned into a predetermined shape. Next, using the metal substrate 1 as a power supply layer, the ground terminal metal for forming the ground terminal is filled to form the ground terminal 4 (FIG. 10B). Next, the method of forming the suspension substrate 10 of this embodiment by peeling off the photoresist 11 can be used (FIG. 10C).
Here, FIGS. 9A to 9C are signal wiring forming steps, and FIGS. 9D to 9F are insulating layer forming steps. FIGS. 10A to 10C show the ground terminal forming step.

  The suspension substrate of this embodiment is used for a magnetic head suspension or the like of a hard disk drive (HDD), and in particular, a magnetic head of a hard disk drive (HDD) having a high-density signal wiring with a narrow pitch. It is suitably used for a suspension substrate.

2. Second Aspect Next, a second aspect of the suspension substrate of the present invention will be described. The suspension substrate of this aspect is the suspension substrate described above, wherein the insulating layer is formed to have a ground terminal opening, and the ground terminal is in contact with the insulating layer in the ground terminal opening. It is the aspect currently formed.
Here, in the suspension substrate of this aspect, the ground terminal is directly formed on the metal substrate, but the ground terminal is directly formed on the metal substrate. As described above, it means that the ground wiring connected to the ground terminal as formed in the conventional suspension substrate is not formed, and that the ground terminal is formed independently.

Such a suspension substrate of this embodiment will be described with reference to the drawings. FIG. 11 is a plan view of the suspension substrate of this embodiment, and FIG. 12 is a cross-sectional view taken along the line AA of FIG. As illustrated in FIGS. 11 and 12, the suspension substrate 10 of this aspect includes a metal substrate 1, an insulating layer 2 formed on the metal substrate 1, and a signal substrate formed on the insulating layer 2. The wiring 3 has a ground terminal 4 directly formed on the metal substrate 1.
Here, the suspension substrate 10 of this embodiment does not include a grounding wiring that is connected to the ground terminal 4, and the insulating layer 2 is formed to have a ground terminal opening 5. The ground terminal 4 is formed in the ground terminal opening 5 so as to be in contact with the insulating layer 2.

According to this aspect, the ground terminal can be easily formed even when the signal wiring having a high density and a narrow pitch is formed, and further, the ground terminal can be miniaturized. Can do. Further, the suspension substrate of this aspect can be easily adjusted in spring characteristics and the like.
Further, since the grounding wiring connected to the ground terminal is not formed, it is possible to prevent a decrease in yield due to poor connection between the ground terminal and the grounding wiring.
Furthermore, since the ground terminal is formed so as to be in contact with the insulating layer, it is easy to make the thickness large, and it is possible to reduce damage and the like.

  The suspension substrate of this embodiment has at least a metal substrate, an insulating layer, signal wiring, and a ground terminal. Hereinafter, each configuration of the suspension substrate according to this aspect will be described. The metal substrate and the signal wiring have the same contents as those described in the section “1. First aspect”, and are not described here.

(1) Ground terminal The ground terminal used in this embodiment is formed directly on the metal substrate and is formed in contact with the insulating layer in the opening for ground terminal formed in the insulating layer described later. It is what.
Here, the ground terminal is directly formed on the metal substrate, as described above, the ground wiring connected to the ground terminal as formed in the conventional suspension substrate is formed. This means that the ground terminal is formed alone.
As described above, the grounding wiring connected to the ground terminal includes not only the case where it is in direct contact with the ground terminal but also the case where it has an electrical connection. In other words, in this embodiment, not only the grounding wire that is in direct contact with the ground terminal, but also the grounding wire that is electrically connected through another layer made of a conductive material is not formed. is there.

  Further, the ground terminal is formed so as to be in contact with the insulating layer, but the ground terminal may be in contact with the insulating layer in the entire periphery in a plan view. The part may be in contact with the insulating layer.

  As the cross-sectional shape of such a ground terminal, it is sufficient if it is in contact with an insulating layer described later. Specifically, as shown in FIGS. 11 and 12 already described, the insulating layer may be in contact with the side wall and the surface in the opening for the ground terminal, and as illustrated in FIG. The insulating layer may be in contact with only the side wall in the ground terminal opening.

The formation position of the ground terminal used in this aspect may be provided at the tip of the suspension substrate on which the magnetic head slider is mounted as illustrated in FIGS. In FIG. 14, when the slider is mounted at the slider installation position 20, the ground terminal 4 is formed at a position where it can be connected to the slider. A signal wiring 3 extended to a position where the slider is connected is formed. Thus, when the magnetic head slider is installed, the ground terminal can be connected to the ground terminal of the magnetic head slider. According to this aspect, since the ground terminal is formed directly on the substrate, it is easily formed even when the signal wiring is formed with a high density and a narrow pitch. Can do. In addition, since a bridge or the like is not required, when used in a hard disk drive or the like, data reading or the like via the slider can be stably performed.
Further, as illustrated in FIG. 15, the ground terminal 4 may be formed so as to surround the slider installation position 20. Usually, since the suspension substrate and the slider are bonded using an adhesive, the ground terminal is formed so as to surround the slider installation position where the suspension substrate and the slider are bonded. This is because it is possible to prevent the adhesive from flowing out.

Furthermore, as shown in FIG. 11 already described, it may be provided in a portion other than the tip of the suspension substrate. In FIG. 11, the ground terminal 4 is formed between the signal wiring 3 and the signal wiring 3. In this case, even when the signal wiring is formed with a high density and a narrow pitch, it can be easily formed. Further, the noise can be reduced.
In addition, when the signal line is provided between the signal lines arranged in the portion other than the tip part of the suspension substrate and is not connected to the magnetic head slider, the ground line extends along the signal line. It is preferable to be formed. This is because the noise removal effect can be improved.

  Here, when the terminal is formed at the tip of the suspension substrate, and when it is formed between the signal wirings other than the tip of the suspension substrate and is not connected to the magnetic head slider, the ground terminal is noise suppression, respectively. It is used as a ground terminal for noise and a ground terminal between wires for noise suppression.

  Further, the magnetic head slider may be provided within a slider installation position, which is a location where the magnetic head slider is installed at the tip of the suspension substrate, so that static electricity stored in the magnetic head slider can be released.

  Here, the formation position in the slider installation position may be any position where the ground terminal is in contact with the insulating layer and can be in contact with the magnetic head slider, but the magnetic head slider is balanced. It is preferable that the position be able to support well. This is because when used in a hard disk drive, the accuracy of data reading and writing can be increased.

Specific examples of the position at which such a magnetic head slider can be supported in a well-balanced manner include those having a plurality of formation regions having a small area, as illustrated in FIG. Further, as illustrated in FIGS. 17A to 17B and FIGS. 18A to 18B, the slider may be formed so as to surround the center portion of the slider installation position. In addition, when there are a plurality of formation regions as shown in FIG. 16 already described, that is, when a plurality of columnar ground terminals are formed, the number of formation is preferably three or more. . This is because the mounted magnetic head slider can be made more excellent in parallelism.
In this aspect, among others, as shown in FIGS. 17 (a) to 17 (b) and FIGS. 18 (a) to 18 (b) described above, the slider is formed so as to surround the central portion. It is preferable that This is because it is possible to prevent the adhesive from flowing out to adhere the magnetic head slider.
Further, as illustrated in FIG. 19, it may be formed at a position connectable to the grounding terminal of the magnetic head slider.
16 to 19 are the same as those in FIG.

  Here, the ground terminal in the case where it is formed in the slider installation position of the suspension substrate is used as a static electricity removing ground terminal.

In this aspect, it can be suitably formed at any of the above-mentioned formation positions, but among these, it is preferable that it is formed in the vicinity of the signal wiring formed at a narrow pitch. This is because the ground terminal can be reduced in size and is in contact with the insulating layer, so that it can be easily formed even between signal wires formed at a narrow pitch.
In addition, in this aspect, the said formation position may be single and may contain 2 or more types. Specifically, it may be formed between the tip portion and the signal wiring other than the tip portion.

The maximum width of the ground terminal used in this embodiment is not particularly limited as long as it can prevent electrostatic breakdown and remove noise, but the ground terminal is circular or rectangular. In this case, it is preferably within a range of 30 μm to 200 μm, and more preferably within a range of 50 μm to 100 μm. This is because, within the above range, even if the signal wiring with a narrow pitch is formed by increasing the density, it can be easily installed. Moreover, in this aspect, since the ground terminal can be reduced in size, the effect of the suspension substrate of the present aspect can be further exhibited by being in the above range.
In the case where the ground terminal is formed in a line shape, the line width is preferably within the range of the maximum width.

  The planar view shape, thickness, resistance value, and type of ground terminal metal used in this aspect are those described in the section “(1) Ground terminal” in “1. First aspect” above. The same contents can be used.

(2) Insulating layer The insulating layer used in this embodiment has a ground terminal opening through which the metal substrate is exposed.

  The shape in plan view of the opening for ground terminal used in this embodiment is not particularly limited as long as it can be filled with a metal for ground terminal to form a ground terminal. , Circular, elliptical, quadrilateral or pentagonal polygonal shapes, comb shapes, cross shapes, rod shapes, and the like.

The maximum width of the ground terminal opening used in the present invention is preferably in the range of 30 μm to 300 μm, particularly 30 μm when the ground terminal opening is circular or rectangular. It is preferable to be in the range of ˜200 μm, and it is particularly preferable to be in the range of 50 μm to 100 μm. This is because the ground terminal formed by filling the ground terminal opening with the ground terminal metal can be miniaturized.
When the ground terminal opening is formed in a line shape, the line width is preferably within the range of the maximum width.

  The material and thickness of the insulating layer used in this embodiment can be the same as those described in the section “(3) Insulating layer” in “1. First embodiment”. Is omitted.

(3) Suspension substrate The suspension substrate of this aspect may have a cover lay (CL) on the insulating layer as necessary. Further, such a coverlay may be formed also on the ground terminal, but the ground terminal is for electrostatic removal of components such as a slider mounted on the suspension substrate. In the case of having a connection portion with a component such as the slider, it is usually formed to have an opening on a connection portion with the component such as the slider of the ground terminal. As the material of the coverlay, the same material as described in the section “(5) Suspension substrate” of “1. First aspect” can be used.

  As a manufacturing method of the suspension substrate according to this aspect, the ground terminal opening is formed in the insulating layer forming step, and the photoresist such as a dry film is applied to the ground terminal in the subsequent ground terminal forming step. The opening is formed so as to surround the opening for use. Next, the ground terminal metal for forming the ground terminal is filled in the ground terminal opening so as to be in contact with the insulating layer, so that the ground terminal is formed except that the ground terminal is formed. A method similar to the manufacturing method of the first aspect can be used.

  The suspension substrate of this embodiment is used for a magnetic head suspension or the like of a hard disk drive (HDD), and in particular, a magnetic head of a hard disk drive (HDD) having a high-density signal wiring with a narrow pitch. It is suitably used for a suspension substrate.

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

Such a suspension of the present invention will be described with reference to the drawings. FIG. 20 is a schematic view showing an example of the suspension of the present invention. As illustrated in FIG. 20, the suspension 30 of the present invention includes the suspension substrate 10 and a load beam 31, and the load beam 31 is provided with a magnetic head slider in the suspension substrate 10. It is adhered to the surface on the side where the slider installation position 20 is not formed.
Here, the suspension substrate is the suspension substrate described in the section “A. Suspension substrate”.
Note that the reference numerals in FIG. 20 are the same as those in FIG.

  According to the present invention, since the suspension substrate is included, electrostatic breakdown and noise can be reduced.

The suspension of the present invention has at least the suspension substrate.
Such a suspension substrate is the same as the content described in the above section “A. Suspension substrate”, and thus the description thereof is omitted here.

  The suspension of the present invention has at least the suspension substrate, but usually has a load beam. As such a load beam, any material can be used as long as it can give a desired rigidity to the suspension when the suspension of the present invention is used in the hard disk drive. Can be used.

  Examples of the use of the suspension of the present invention include a suspension with a head of a hard disk drive, and in particular, it is suitably used for a suspension with a head that requires less electrostatic breakdown and noise.

C. Next, the suspension with a head according to the present invention will be described. A suspension with a head according to the present invention includes the suspension and a magnetic head slider mounted on the suspension.

Such a suspension with a head according to the present invention will be described with reference to the drawings. FIG. 21 is a schematic view showing an example of a suspension with a head according to the present invention. As illustrated in FIG. 21, the suspension with head 40 of the present invention includes the suspension 30 and a magnetic head slider 41 mounted on a slider installation position on the suspension 30.
Here, the suspension is the suspension described in the section “B. Suspension”.
Note that the reference numerals in FIG. 21 are the same as those in FIG.

  According to the present invention, since the suspension is included, electrostatic breakdown and noise can be reduced.

The suspension with a head of the present invention has at least the suspension and the magnetic head slider.
The suspension is the same as that described in the section “B. Suspension”, and thus the description thereof is omitted here.

  The magnetic head slider used in the present invention is not limited as long as it can write and read data on the disk when the suspension with a head of the present invention is used in a hard disk drive. What is used can be used.

  Examples of the use of the suspension with a head of the present invention include a hard disk drive, and among these, it is preferably used for a hard disk drive that is required to have less electrostatic breakdown and noise.

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.

Such a hard disk drive of the present invention will be described with reference to the drawings. FIG. 22 is a schematic plan view showing an example of the internal structure of the hard disk drive of the present invention. As illustrated in FIG. 22, the hard disk drive 50 of the present invention includes a suspension 40 with a head, a disk 51 on which data is written to and read from the suspension 40 with a head, and a spindle motor 52 that rotates the disk 51. An arm 53 connected to the suspension 40 with the head, a voice coil motor 54 that moves the slider of the suspension 40 with the head to a desired position on the disk 51 by moving the arm 53, and the above And a case 55 for sealing each component.
Here, the suspension with a head is the suspension described in the section “C. Suspension with a head”.

  According to the present invention, since the suspension with the head is included, the electrostatic breakdown and noise can be reduced. As a result, the data reliability and the like can be improved.

The hard disk drive of the present invention has at least the above suspension with a head.
Such a suspension with a head is the same as the content described in the section “C. Suspension with a head”, and therefore, description thereof is omitted here.

  The hard disk drive of the present invention has at least the above suspension with a head, but usually has a disk, a spindle motor, an arm, and a voice coil motor. As such a disk, a spindle motor, an arm, and a voice coil motor, those generally used for hard disk drives 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]
A SUS304 (metal substrate) with a thickness of 20 μm, a polyimide layer (insulating layer forming layer) with a thickness of 10 μm, and a Cu wiring layer (signal wiring forming layer) made of electrolytic copper with a thickness of 9 μm in this order. By preparing a laminated body, and performing chemical etching, electrolytic plating, etc. described below on this laminated body, the maximum width as shown in FIG. 4 is narrower than the conventional one, and further directly formed on the metal substrate, A suspension substrate having an independent ground terminal was obtained.

  First, the Cu wiring layer of the laminated body was chemically etched to form a signal wiring having a line width of 25 μm and an interval of 25 μm at the narrowest portion.

  Next, an insulating layer having a pattern that exposes a metal substrate in a region including a slider installation position, where the slider is mounted, by patterning a polyimide layer having a thickness of 10 μm by chemical etching using a photosensitive resist. Formed.

  Subsequently, a line-shaped opening having a line width of 60 μm and surrounding the slider installation position is formed in the region where the metal substrate is exposed, which is formed to form the slider installation position. A dry film resist having a thickness of 40 μm was formed (applied) on a metal substrate. Next, electrolytic nickel plating was performed using the metal substrate as a power feeding layer to form a ground terminal having a thickness of 25 μm from the surface of the metal substrate to the surface of the nickel plating in the opening of the dry film. In this way, a suspension substrate having a ground terminal formed directly was formed on the metal substrate in the region where the metal substrate formed to form the slider installation position was exposed.

In this way, the suspension having the grounding means in which the ground terminal is directly formed on the metal substrate of the portion that is difficult to mount by the conventional grounding means composed of the ground terminal and the grounding wiring connected to the ground terminal. A substrate was obtained.
Further, the resistance value at the ground terminal of the obtained suspension substrate was 0.2Ω, and the same characteristics as those of the ground terminal in the grounding means of the conventional suspension substrate could be obtained.
Further, in the conventional grounding means composed of the ground terminal and the grounding wiring connected to the ground terminal, the maximum width of the entire grounding means including the ground terminal and the grounding wiring is usually about 270 μm. In this example, the maximum width of the ground terminal was 60 μm, and could be formed with a smaller dimension.

It is a schematic plan view which shows an example of the 1st aspect of the board | substrate for suspensions of this invention. It is a schematic sectional drawing which shows an example of the 1st aspect of the board | substrate for suspensions of this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is process drawing which shows an example of the manufacturing method of the board | substrate for suspensions of this invention. It is process drawing which shows an 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 2nd aspect of the board | substrate for suspensions of this invention. It is a schematic sectional drawing which shows an example of the 2nd aspect of the board | substrate for suspensions of this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is explanatory drawing explaining the ground terminal used for this invention. It is the schematic which shows an example of the suspension of this invention. It is the schematic which shows an example of the suspension with a head of this invention. It is the schematic which shows an example of the internal structure of the hard-disk drive of this invention. It is a schematic plan view which shows an example of the conventional board | substrate for suspensions. It is a schematic sectional drawing which shows an example of the conventional board | substrate for suspensions.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101 ... Metal substrate 2,102 ... Insulating layer 2 '... Insulating layer forming layer 3, 103 ... Signal wiring 3' ... Signal wiring forming layer 4, 104 ... Ground terminal 5, 105 ... Ground terminal Ground terminal Opening 106 ... Grounding wiring 10, 100 ... Suspension substrate 11 ... Photoresist 20 ... Slider installation position 30 ... Suspension 40 ... Suspension with head 50 ... Hard disk drive

Claims (7)

A metal substrate;
An insulating layer formed on the metal substrate;
A signal wiring formed on the insulating layer;
A ground terminal which is formed directly on the metal substrate,
A cover lay formed on the insulating layer ,
The insulating layer is formed to have a ground terminal opening, and the ground terminal is formed in contact with the insulating layer in the ground terminal opening,
The ground terminal is in contact with the side wall and the surface in the opening for the ground terminal of the insulating layer,
The ground terminal is formed to support the magnetic head slider in a slider installation position, which is an area where the magnetic head slider is mounted,
The suspension substrate, wherein the cover lay has an opening in the entire area of the magnetic head slider installation position . 2. The suspension board according to claim 1, wherein the ground terminal is made of only nickel . 3. The suspension substrate according to claim 1, wherein a plurality of the ground terminals are formed in a plurality of positions within the slider installation position . The suspension substrate according to any one of claims 1 to 3, wherein the ground terminal is capable of maintaining parallelism of the magnetic head slider with the metal substrate. A suspension comprising the suspension substrate according to any one of claims 1 to 4 . 6. A suspension with a head, comprising the suspension according to claim 5 and a magnetic head slider mounted on the suspension. A hard disk drive comprising the suspension with a head according to claim 6 .

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