JP2001256627A - Head gimbal assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an HGA, capable of performing high-speed data transfer for writing/reading by reducing the parasitic capacitance between a lead pattern and a ground, so as to shift the resonance point to a high-frequency side. SOLUTION: This HGA is provided with a magnetic head slider, a metallic suspension for supporting the magnetic head slider, and a magnetic head leading pattern formed on the suspension via an insulator, and a metal flexure and a load beam downward of the magnetic head lead pattern are partially removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a head gimbal assembly (HGA) in a magnetic disk drive or a magneto-optical disk drive.

[0002]

2. Description of the Related Art In an HGA, forming a lead pattern for a magnetic head on a metal suspension is disclosed in, for example, JP-A-6-215513 and JP-A-3-315.
It is known from, for example, JP-A-71477.

Japanese Patent Application Laid-Open No. Hei 6-215513 discloses that a wiring pattern for a magnetic head is formed on a load beam by photolithography. On the other hand, Japanese Patent Application Laid-Open No. 3-71477 discloses a suspension in which a metal layer having a conductive wire portion for making an electrical connection is bonded to one surface of a flexible sheet and stainless steel is bonded to the other surface. I have.

[0004]

In any of these known techniques, a lead pattern connected to a magnetic head is formed on a base metal via an insulating layer.
Therefore, a capacitor is formed between the lead pattern and the base metal. Since the base metal is at the ground level, a parasitic capacitance _CG is generated between the lead pattern and the ground. When such parasitic capacitance is generated, and the parasitic capacitance C _G, by the inductance component of the parasitic inductance and the magnetic head of the lead pattern, a resonance phenomenon occurs in the data transfer frequency. Hereinafter, this resonance phenomenon will be described.

FIGS. 1 and 2 show equivalent circuits on a write head side and a read head side in a conventional HGA having a composite type magnetic head, respectively. In these figures, 10 is an inductive write magnetic head,
Numeral 11 denotes a read pattern, 20 denotes a magnetoresistive read magnetic head, and 21 denotes an equivalent circuit of the read pattern.

In FIG. 1, the parasitic capacitance _CG is C _G = 40.
pF, the parasitic inductance L _L of the lead pattern is L _L
= 20 nH, the inductance component _{L H} of inductive write magnetic head is assumed to be approximately _L H = _90nH, write resonant frequency _{f 0, f 0 = 1 / 2π√ (} LC) ≒ 1 / 2π√ {(L H + L
_L ) C _G ｝ ≒ 76 MHz. That is, resonance occurs at about 76 MHz, and write data transfer at frequencies higher than that becomes impossible. However,
_{L ≒ L H + L L,} C ≒ C G (C G »C L, C L is the parasitic capacitance between the lead patterns) are.

Similarly, in FIG. 2, the parasitic capacitance _CG is C
_G = 40 pF, parasitic inductance L of the lead pattern
When _L is _L L = 20 nH, magnetoresistive read magnetic head inductance _{l P} is assumed to be about _l P = 30 nH, reading the resonance frequency _{f 0 is, f 0 = 1 / 2π√ (} LC) ≒ 1 / 2π√ ｛(l _P + L
_L ) C _G ｝ ≒ 116 MHz. That is, resonance occurs at about 116 MHz, and reading data transfer at frequencies higher than that becomes impossible. _{However, L ≒ l P + L L} , C ≒ C G (C G »C L, the _{C L} parasitic capacitance between the lead patterns) are.

Accordingly, an object of the present invention is to provide an HGA in which the resonance point is shifted to the high frequency side by reducing the parasitic capacitance between the lead pattern and the ground, thereby enabling high-speed data transfer of writing and reading. It is in.

[0009]

SUMMARY OF THE INVENTION The present invention relates to an HGA having a magnetic head slider, a metal suspension for supporting the magnetic head slider, and a magnetic head lead pattern formed on the suspension via an insulator. Things. In particular, according to the present invention, the suspension comprises a metal load beam, and a metal flexure mounted on the load beam and a magnetic head lead pattern formed thereon, and the suspension below the magnetic head lead pattern. A part of the metal flexure and a part of the load beam below the magnetic head lead pattern are removed.

The parasitic capacitance between the lead pattern and the metal suspension is reduced by partially removing the metal flexure and the load beam below the magnetic head lead pattern. That is, in order to reduce the parasitic capacitance, the distance d between the metal suspension and the lead pattern is increased, the dielectric constant ε ₀ of the insulator between the metal suspension and the lead pattern is reduced, What is necessary is to reduce the opposing area S between the lead pattern and the lead pattern because the capacitance C ≒ ε ₀
It can be understood from the equation of S / d.

However, with respect to increasing the thickness of the insulator between the metal suspension and the lead pattern so as to increase the distance d, the flexibility of the suspension is impaired, which is a functional problem. . In addition, there is hardly any insulating material having a relative dielectric constant smaller than that of currently used polyimide (ε ₀ = 3.3) and having the function of an interlayer insulating film. Therefore, in the present invention, the parasitic capacitance is reduced by partially removing the metal flexure and the load beam below the magnetic head lead pattern to reduce the facing area S between the metal suspension and the lead pattern. I have.
In order to reduce the facing area S, it is conceivable to reduce the width of the lead pattern. However, this leads to an increase in DC resistance, which leads to deterioration of signal transfer characteristics.
In order not to increase the DC resistance, it is conceivable to increase the thickness of the lead pattern by reducing the width of the lead pattern. However, not only is it difficult to create such a thin and thick lead pattern, but also the flexibility of the suspension is increased. Greatly degrades the performance.

In one embodiment of the present invention, a plurality of through holes are provided in a metal flexure below a magnetic head lead pattern.

In another embodiment of the present invention, a plurality of through holes are provided in a load beam below a magnetic head lead pattern.

Further, according to the present invention, the metal suspension below the magnetic head lead pattern may be provided with a concave portion for reducing parasitic capacitance. By providing such a concave portion, the distance d between the metal suspension and the lead pattern is increased, and the facing area S
Can be reduced, thereby reducing the parasitic capacitance.

The suspension comprises a metal load beam,
It is preferable that the magnetic head lead pattern placed on the load beam be a metal flexure formed thereon, and the metal flexure beneath the magnetic head lead pattern be provided with a plurality of recesses.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings.

FIG. 3 is a plan view showing a reference example of the HGA related to the present invention, and FIG. 4 is a sectional view taken along line AA of FIG.

In these figures, 30 is a flexible flexure for supporting the magnetic head slider 31 at one end, 32 is a load beam for supporting and fixing the flexure 30, and 33 is fixed to the base of the load beam 32. Each of the illustrated base plates is shown. Note that the base of the load beam 32 may be configured as a flexure without separately providing the flexure.

In this embodiment, the flexure 30 is made of a stainless steel plate (for example, SUS304T) having a thickness of about 25 μm.
A). On the flexure 30, four lead patterns 34a to 34d of thin film patterns are formed over almost the entire length as input / output signal lines. One end of each of the lead patterns 34a to 34d is connected to four connection terminals (not shown) of a thin film pattern directly connected to the magnetic head slider 31, and the other end is connected by a thin film pattern for connecting to an external circuit. They are connected to terminals 35a to 35d.

The thin film pattern is formed by a known patterning method in which a printed board is laminated on a thin metal plate. 4, a polyimide layer (lower insulating layer) 36 having a thickness of about 5 μm, copper layers (lead patterns) 34 a to 34 d having a thickness of about 4 μm, and a polyimide layer having a thickness of about 5 μm. It is formed by laminating (upper insulating layer) 37 on the flexure 30 in this order, or by laminating a laminate on the flexure 30 in advance. However, the connection terminals (35a to 3
In the portion 5d), a nickel layer and a gold layer are laminated on the copper layer, and the upper insulating layer is not formed thereon. In FIG. 3, the lead patterns 34a to 34d are represented by solid lines for easy understanding.

The load beam 32 is made of a stainless steel plate of about 62 to 76 μm, and supports the flexure 30 in several places. This fixation between the flexure 30 and the load beam 32 is performed at a plurality of welding points by laser welding or the like.

The base plate 33 is made of stainless steel or iron.
At a plurality of welding points.

The most important configuration in this embodiment is that a plurality of through holes 38 are formed in the stainless steel plate of the flexure 30 by, for example, etching. That is, the lead patterns 34 a to 34 of the flexure 30
A plurality of stainless steel plate through-holes 38 are provided in a portion located below d to substantially reduce the area of the flexure, which is an electrode facing the lead pattern, thereby reducing the parasitic capacitance caused by the capacitor formed by the lead pattern and the flexure. That is, the capacitance _CG is reduced. In the present reference example, actually, the electrode facing the lead pattern at the portion of the through hole 38 is set as the load beam 32,
The distance between the electrodes of the capacitor is increased. Further, since the mass of the suspension itself can be reduced by providing the through holes in the flexure, the mechanical resonance characteristics and dynamic vibration characteristics of the entire suspension can be greatly improved.

In this embodiment, the shape of the through hole 38 is an ellipse. However, this shape may be a rectangle, another polygon, or any other shape. There may be. Further, the shapes of the through holes may be the same or different. The sizes of the through holes 38 are not limited to those shown in the drawings, and may be different from each other. However, in order to satisfy the basic function as a flexure, the through hole 38 is formed so as to secure the resiliency required for the magnetic head slider 31 to move freely, and at a position other than the welding point with the load beam 32. Form. Unwanted metal parts to ensure the basic functionality of the flexure 30, be removed all by forming a through hole 38, in order to significantly reduce the parasitic capacitance C _G desirable. 1/2 of flexure area
Parasitic capacitance C _G becomes about 20pF if rid of, that much parasitic capacitance C _G decreases Further, reducing the area.

By forming the plurality of through holes 38 in this manner, the lower insulating layer 36, the lead patterns 34a to 34d and the upper insulating layer 3 laminated on the flexure 30 are formed.
In order to maintain the strength, the insulating layers 36 and 37 are within an allowable range because the structure 7 is bridged on the through hole.
Of the lead patterns 34a-34
It is preferable to increase the thickness and width of d.

FIG. 5 is a plan view showing an embodiment of the HGA of the present invention, and FIG. 6 is a sectional view taken along line BB of FIG.

In these figures, 50 is a flexible flexure for supporting the magnetic head slider 51 at one end, 52 is a load beam for supporting and fixing the flexure 50, and 53 is fixed to the base of the load beam 52. Each of the illustrated base plates is shown. Note that the base of the load beam 52 may be configured as a flexure without separately providing the flexure.

In this embodiment, the flexure 50 is made of a stainless steel plate (for example, SUS304T) having a thickness of about 25 μm.
A). On the flexure 50, four lead patterns 54a to 54d of thin film patterns are formed over almost the entire length as input / output signal lines. One end of each of the lead patterns 54a to 54d is connected to four connection terminals (not shown) of a thin film pattern directly connected to the magnetic head slider 51, and the other end is connected by a thin film pattern for connecting to an external circuit. Connected to terminals 55a to 55d.

The thin film pattern is formed by a known patterning method in which a printed board is laminated on a metal thin plate. 6, a polyimide layer (lower insulating layer) 56 having a thickness of about 5 μm, copper layers (lead patterns) 54 a to 54 d having a thickness of about 4 μm and a polyimide layer having a thickness of about 5 μm. The (upper insulating layer) 57 is formed by laminating on the flexure 50 in this order, or laminating a laminate in advance on the flexure 50. However, connection terminals (55a-5
In the portion 5d), a nickel layer and a gold layer are laminated on the copper layer, and the upper insulating layer is not formed thereon. In FIG. 5, the lead patterns 54a to 54d are represented by solid lines for easy understanding.

The load beam 52 is made of a stainless steel plate of about 62 to 76 μm, and supports the flexure 50 in several places. This fixation between the flexure 50 and the load beam 52 is performed at a plurality of welding points by laser welding or the like.

The base plate 53 is made of stainless steel or iron.
At a plurality of welding points.

The most important structure in this embodiment is that the stainless steel plate of the flexure 50 has a plurality of through holes 58 formed by, for example, etching, and the load beam 52 has a plurality of through holes 59 formed by, for example, etching. There is in the point. That is, flexure 5
A plurality of stainless steel plate through-holes 58 are provided in a portion of the load beam 52 below the lead patterns 54a to 54d, and a plurality of through-holes 59 are provided in the load beam 52 below the through-holes 58, respectively. Thus, by substantially reducing the area of the flexure and the load beam is an electrode opposed to the lead pattern, since reducing the parasitic capacitance C _G of the capacitor formed by the lead pattern and the flexure and load beam is there. Further, since the mass of the suspension itself can be reduced by providing the through holes in the flexure and the load beam, the mechanical resonance characteristics and the dynamic vibration characteristics of the entire suspension can be greatly improved.

In this embodiment, the through holes 58 and 5
Although the shape of 9 is an ellipse, this shape may be a rectangle, another polygon, or any other shape. The shapes of the through holes 58 or the through holes 58 and 59 may be the same or different. The sizes of the through holes 58 and 59 are not limited to those illustrated, and may be different from each other. Further, in the present embodiment, the through hole 58
Are larger than the through hole 59, but they may be the same size, or the through hole 58 may be smaller than the through hole 59. However, in order to satisfy the basic function as a flexure, the through hole 58 is formed so as to secure a spring property necessary for the magnetic head slider 51 to move freely, and at a position other than a welding point with the load beam 52. Form. The through hole 59 is also formed at a position other than the welding point with the flexure 50. Flexure 5
0 and unnecessary metal parts to ensure the basic functionality of the load beam 52, to remove any by forming a through hole 58 and 59, in order to significantly reduce the parasitic capacitance C _G desirable. Parasitic capacitance _{C G} if rid of half the area of the flexure and load beam about 20p
F, and if the area is further reduced, the parasitic capacitance _CG is reduced accordingly.

By forming a plurality of through holes 58 in this manner, the lower insulating layer 56, the lead patterns 54a to 54d and the upper insulating layer 5 laminated on the flexure 50 are formed.
7 has a structure in which a bridge is formed on the through-hole, so that the insulating layers 56 and 57 are within an allowable range in order to maintain the strength.
Of the lead patterns 54a-54
It is preferable to increase the thickness and width of d.

FIG. 7 is a plan view showing another embodiment of the HGA of the present invention, and FIG. 8 is a sectional view taken along line CC of FIG.

In these figures, 70 is a flexible flexure for supporting a magnetic head slider 71 at one end, 72 is a load beam for supporting and fixing the flexure 70, and 73 is fixed to the base of the load beam 72. Each of the illustrated base plates is shown. Note that the base of the load beam 72 may be configured as a flexure without separately providing the flexure.

In this embodiment, the flexure 70 is made of a stainless steel plate (for example, SUS304T) having a thickness of about 25 μm.
A). On the flexure 70, four lead patterns 74a to 74d of thin film patterns are formed over almost the entire length as input / output signal lines. One end of each of the lead patterns 74a to 74d is connected to four connection terminals (not shown) of a thin film pattern directly connected to the magnetic head slider 71, and the other end is connected by a thin film pattern for connecting to an external circuit. They are connected to terminals 75a to 75d.

The thin film pattern is formed by a known patterning method in which a printed circuit board is laminated on a thin metal plate. 8, a polyimide layer (lower insulating layer) 76 having a thickness of about 5 μm, copper layers (lead patterns) 74a to 74d having a thickness of about 4 μm, and a polyimide layer having a thickness of about 5 μm. The upper insulating layer 77 is formed by laminating in advance the layers 77 in this order on the flexure 70. However, in the portions of the connection terminals (75a to 75d), a nickel layer and a gold layer are laminated on the copper layer, and the upper insulating layer is not formed thereon. In FIG. 7, the lead patterns 74a to 74d are indicated by solid lines for easy understanding.

The load beam 72 is made of a stainless steel plate of about 62 to 76 μm, and supports the flexure 70 in several places. This fixation between the flexure 70 and the load beam 72 is made at a plurality of welding points by laser welding or the like.

The base plate 73 is made of stainless steel or iron.
At a plurality of welding points.

The most important configuration in this embodiment is that a plurality of concave portions (blind holes) 78 are formed in the flexure 70 by, for example, half etching. That is,
A plurality of recesses 78 are provided in a portion of the flexure 70 located below the lead patterns 74a to 74d to increase the distance between the electrodes of the capacitor due to the lead pattern and the flexure which is an electrode facing the lead pattern. _G is decreasing. In addition, since the flexure is provided with a concave portion, the mass of the suspension itself can be reduced, so that the mechanical resonance characteristics and dynamic vibration characteristics of the entire suspension can be significantly improved.

In the present embodiment, the shape of the concave portion 78 is an ellipse. However, the shape may be a rectangle, another polygon, or any other shape. You may. Further, the shapes of the concave portions may be the same or different. The size of the concave portion 78 is not limited to the illustrated one, and may be different from each other. However, in order to satisfy the basic function as a flexure, the concave portion 78 is formed so as to secure a spring property necessary for the magnetic head slider 71 to move freely, and is formed at a position other than a welding point with the load beam 72. I do. Forming a recess 78 in the unnecessary parts to ensure the basic functionality of the flexure 70, but in order to greatly reduce the parasitic capacitance C _G desirable.

By forming the plurality of recesses 78 in this manner, the lower insulating layer 7 laminated on the flexure 70 is formed.
6. Lead patterns 74a to 74d and upper insulating layer 77
Has a structure in which a bridge is formed over the concave portion. In order to maintain its strength, the thicknesses of the insulating layers 76 and 77 are made large and the thicknesses and widths of the lead patterns 74a to 74d are made large within an allowable range. Is preferred.

FIG. 9 is a plan view showing another reference example of the HGA related to the present invention, and FIG. 10 is a sectional view taken along line DD of FIG.

In these figures, 90 is a flexible flexure for supporting a magnetic head slider 91 at one end, 92 is a load beam for supporting and fixing the flexure 90, and 93 is fixed to the base of the load beam 92. Each of the illustrated base plates is shown. Note that the base of the load beam 92 may be configured as a flexure without separately providing the flexure.

In this embodiment, the flexure 90 is formed of a stainless steel mesh plate having a thickness of about 25 μm. On the flexure 90, four lead patterns 94a of a thin film pattern are provided as input / output signal lines.
To 94d are formed over substantially the entire length thereof. One end of each of the lead patterns 94a to 94d is connected to four connection terminals (not shown) of a thin film pattern directly connected to the magnetic head slider 91, and the other end is connected by a thin film pattern for connecting to an external circuit. Terminals 95a-
95d.

The thin film pattern is formed by a known patterning method in which a printed board is laminated on a metal thin plate. That is, as is apparent from FIG.
Polyimide layer (lower insulating layer) 96, and patterned copper layers (lead patterns) 94a to 94d having a thickness of about 4 μm.
And a polyimide layer (upper insulating layer) 97 having a thickness of about 5 μm is laminated on the flexure 90 in this order, or is laminated on the flexure 90 in advance. However, connection terminals (95a-
In the part 95d), a nickel layer and a gold layer are laminated on the copper layer, and the upper insulating layer is not formed thereon. In FIG. 9, the lead patterns 94a to 94d are shown by solid lines for easy understanding.

The load beam 92 is made of a stainless steel plate of about 62 to 76 μm, and supports the flexure 90 in several places. This fixation between the flexure 90 and the load beam 92 is made at a plurality of welding points by laser welding or the like.

The base plate 93 is made of stainless steel or iron.
At a plurality of welding points.

The most important structure in this embodiment is a flexure 90 excluding an end portion 90a for supporting a magnetic head slider 91 as shown in FIG. 11, which partially shows a flexure plane excluding a lead pattern. 90
b is in a mesh structure when viewed from a plane.
Thus, by substantially reducing the area of the flexure is an electrode opposed to the lead pattern is're reduces the parasitic capacitance C _G of the capacitor formed by the lead pattern and the flexure. Further, since the flexure has a mesh structure, the mass of the suspension itself can be reduced, so that the mechanical resonance characteristics and dynamic vibration characteristics of the entire suspension can be greatly improved.

The above-mentioned mesh structure has a structure that can secure the spring property necessary for the magnetic head slider 91 to move freely in order to satisfy the basic function as a flexure.

FIG. 12 is a perspective view schematically showing a configuration of a main part of an example of a hard disk device having an HGA of the present invention.

In the figure, reference numeral 120 denotes a plurality of magnetic disk media rotating around an axis 121, and 122 denotes an assembly carriage device for positioning a magnetic head slider on a track. The assembly carriage device 122 mainly includes a carriage 124 that can rotate around a shaft 123 and an actuator 125 that drives the carriage 124 to rotate, for example, a voice coil motor (VCM).

A base of a plurality of drive arms 126 stacked in the direction of the axis 123 is attached to the carriage 124.
127 is fixed. Each HGA 127 is provided at the distal end of the drive arm 126 such that the magnetic head slider 128 provided at the distal end thereof faces the surface of each magnetic disk medium 120.

In this embodiment, only each drive arm 126 or the carriage 124 including each drive arm 126 is formed of a non-conductive material such as plastic or ceramic. As a modification of this embodiment, the drive arm 126 is made of metal,
The bearing portion 23 may be formed of a non-conductive material such as plastic or ceramic. By this, H
The GA 127 is electrically insulated from the housing ground of the hard disk drive.

FIG. 13 shows an equivalent circuit of a lead pattern portion in this example. In the figure, the parasitic capacitance C _G
Is C _G 40 pF, and the minimum parasitic capacitance C _V of the lead pattern caused by the insulation of the HGA is C _V ≒ 5 pF, the combined parasitic capacitance C _G ′ is C _G ′ = C _G C _V / (C _G + C _V ) ≒ 40 × 5 / (40
+5) ≒ 4.4 pF. As described above, since the HGA floats from the housing ground, the substantial parasitic capacitance C _G ′ between the lead pattern and the ground is significantly reduced.

As described above, if the HGA is completely insulated from the ground in a DC manner, there is a possibility that a trouble due to the generation of static electricity may occur. Therefore, the HGA is actually insulated as shown in an equivalent circuit shown in FIG. A high-resistance pure resistor RH is inserted between the HGA and the chassis ground.

FIG. 15 is a partial sectional view schematically showing a partial configuration of another example of the hard disk device having the HGA of the present invention.

In the figure, 150 is a drive arm attached to the carriage, 151 is a base plate of the HGA attached to the drive arm 150, and 152 is a flexible member for supporting the magnetic head slider 153 at one end. Flexures 154 indicate HGA load beams for supporting and fixing the flexure 152, respectively.
The base of the load beam 154 is fixed to the base plate 151.

The base plate 151 of the HGA is fixed to the drive arm 150 via a non-conductive member (or sheet) 155, so that the HGA is electrically insulated from the hard disk drive housing ground. Have been. Because the HGA floats from the chassis ground,
A substantial parasitic capacitance C between the lead pattern and the ground
_G ′ is greatly reduced.

As described above, if the HGA is completely insulated from the ground in a direct current manner, a trouble due to the generation of static electricity may occur. Therefore, the HGA is actually insulated as shown in an equivalent circuit shown in FIG. A high-resistance pure resistor RH is inserted between the HGA and the chassis ground.

The embodiments described above are merely examples of the present invention, and do not limit the present invention. The present invention can be embodied in other various modifications and alterations. Therefore, the scope of the present invention is defined only by the appended claims and their equivalents.

[0063]

As described above in detail, according to the present invention, since the metal flexure and the load beam below the magnetic head lead pattern are partially removed, the facing area between the metal suspension and the lead pattern is reduced. And the parasitic capacitance between the lead pattern and the metal suspension is reduced. As a result, the parasitic capacitance between the lead pattern and the ground is reduced, so that the resonance point is shifted to the high frequency side, and high-speed data transfer for writing and reading becomes possible. In addition, since the mass of the suspension itself can be reduced by partially removing the suspension, the mechanical resonance characteristics and dynamic vibration characteristics of the entire suspension can be significantly improved.

Further, according to the present invention, since the metal flexure below the magnetic head lead pattern is provided with a recess for reducing the parasitic capacitance, the distance between the metal flexure and the lead pattern is increased and the facing area is increased. Can be reduced, thereby reducing the parasitic capacitance. As a result, the parasitic capacitance between the lead pattern and the ground is reduced, so that the resonance point is shifted to the high frequency side, and high-speed data transfer for writing and reading becomes possible. Further, by providing the concave portion in this manner, the mass can be reduced without greatly reducing the strength of the suspension itself, so that the mechanical resonance characteristics and dynamic vibration characteristics of the entire suspension can be significantly improved.

[Brief description of the drawings]

FIG. 1 is an equivalent circuit on a write head side in a conventional HGA having a composite type magnetic head.

FIG. 2 is an equivalent circuit on a read head side in a conventional HGA having a composite type magnetic head.

FIG. 3 is a plan view showing a reference example of an HGA related to the present invention.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

FIG. 5 is a plan view showing an embodiment of the HGA of the present invention.

FIG. 6 is a sectional view taken along line BB of FIG. 5;

FIG. 7 is a plan view showing another embodiment of the HGA of the present invention.

FIG. 8 is a sectional view taken along line CC of FIG. 7;

FIG. 9 is a plan view showing another reference example of the HGA related to the present invention.

FIG. 10 is a sectional view taken along line DD of FIG. 9;

11 is a diagram illustrating a partial plane of a flexure excluding a lead pattern in the reference example of FIG. 9;

FIG. 12 is a perspective view schematically showing a configuration of a main part of an example of a hard disk device having an HGA of the present invention.

13 is an equivalent circuit of a suspension part in the example of FIG.

FIG. 14 is an equivalent circuit of a suspension portion when a high resistance for preventing static electricity is connected in the example of FIG. 12;

FIG. 15 is a partial cross-sectional view schematically showing a partial configuration of another example of the hard disk device including the HGA of the present invention.

[Explanation of symbols]

30, 50, 70, 90, 152 Flexure 31, 51, 71, 91, 128, 153 Magnetic head slider 32, 52, 72, 92, 154 Load beam 33, 53, 73, 93, 151 Base plate 34a to 34d, 54a ~ 54d, 74a ~ 74d, 9
4a to 94d Lead patterns 35a to 35d, 55a to 55d, 75a to 75d, 9
5a to 95d Connection terminals 36, 37, 56, 57, 76, 77, 96, 97 Insulation layers 38, 58, 59 Through holes 78 Depressions 120 Magnetic disk media 121, 123 Axis 122 Assembly carriage device 124 Carriage 125 Actuator 126, 150 Drive arm 127 HGA 155 Non-conductive member (or sheet)

Claims (5)

[Claims] 1. A head gimbal assembly comprising: a magnetic head slider; a metal suspension supporting the magnetic head slider; and a magnetic head lead pattern formed on the suspension via an insulator. Comprises a metal load beam, and a metal flexure mounted on the load beam and having the magnetic head lead pattern formed thereon, and one of the metal flexures below the magnetic head lead pattern. And a part of the load beam below the magnetic head and the lead pattern for the magnetic head is removed. 2. The head gimbal assembly according to claim 1, wherein a plurality of through holes are provided in the metal flexure below the magnetic head lead pattern. 3. The head gimbal assembly according to claim 2, wherein a plurality of through holes are provided in the load beam below the magnetic head lead pattern. 4. A head gimbal assembly comprising: a magnetic head slider; a metal suspension supporting the magnetic head slider; and a magnetic head lead pattern formed on the suspension with an insulator interposed therebetween. A head gimbal assembly, wherein a recess for reducing parasitic capacitance is provided in the metal suspension below the head lead pattern. 5. The suspension according to claim 1, wherein the suspension comprises a metal load beam and a metal flexure mounted on the load beam and having the magnetic head lead pattern formed thereon. The head gimbal assembly according to claim 4, wherein a plurality of recesses are provided in the lower metal flexure.