JPH09134514A - Manufacture of suspension for magnetic disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a suspension for a magnetic disk device by which the shape of a suspension can be accurately formed and an insulating layer of uniform thickness is formed by forming a base board in the shape of a suspension, forming an insulating layer on the base board by a screen printing method and forming a wiring pattern on the insulating layer. SOLUTION: A stainless steel base board is formed in the shape of a suspension 11 by etching. Next, the precursor of polyimide is applied to the stainless steel plate formed in the shape of a suspension by a screen printing method. The base board to which the precursor of polyimide is applied is set inside a furnace, and the temperature of the furnace is increased to harden by heating the precursor of polyimide. Next, exposure treatment and developing treatment are applied to semi-hardened polyimide. After that, the stainless steel base board in which the polyimide is patterned is set again inside the furnace to completely imidize the semi-hardened polyimide, thereby forming an insulating layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floating head slider (hereinafter referred to as slider) equipped with a magnetic head for reading signals from and writing signals to a magnetic disk provided in a magnetic disk device. The present invention relates to a method of manufacturing a suspension to be supported.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for miniaturizing magnetic disk devices, such as hard disk drives, and increasing their capacity. To address this requirement,
It is necessary to reduce the shape of the slider provided in the hard disk drive and reduce the flying height thereof.
For example, it is necessary to have a shape having a length of 2 mm or less, a width of 1.6 mm or less, and a thickness of 0.43 mm or less and a flying height of 0.1 μm or less. FIG. 5 is a perspective view showing a peripheral portion of a conventional slider. A magnetic head is mounted on the slider 21, and the slider 21 is a suspension 22.
Supported by The suspension 22 has a rectangular gimbal 23 to which a magnetic head is attached, and a load beam 25 to which a gimbal 23 is attached at one end and a base plate 24 having an arm (not shown) at the other end. It is composed by. A lead wire 26 that connects a terminal of the slider 21 and a terminal of a drive circuit (not shown) is provided around the suspension 22.

By the way, as a recent magnetic head, an MR head utilizing a magnetoresistive effect has been used for reproduction. However, when using this MR head,
Since it is also necessary to mount an inductive head for recording on the slider, the number of lead wires connecting the terminals of these magnetic heads and the terminals of the drive circuit will be double that of the conventional one. Therefore, there is a problem that the slider is easily affected by the lead wire, and as a result, the flying height changes.

As a method of solving this problem, there is a method of forming a lead wire with a thin film on the suspension. This is because without directly connecting the terminals of the magnetic head to the lead wires,
This is a method of connecting a terminal of a magnetic head and a thin film lead wire formed on a suspension. According to this method,
In particular, when the gimbal and the load beam forming the suspension are integrally formed, the thin film lead wire can be extended to the arm attachment portion of the suspension, which is advantageous in use.

The cross-sectional structure of this thin film lead wire is, for example, as described in Japanese Patent Laid-Open No. 6-215513.
It has a three-layer structure including a lower layer, an insulating layer, a wiring pattern layer, and a protective layer. A method of manufacturing the suspension in which the thin film lead wire is formed will be described with reference to the flowchart of FIG. A poly-imide precursor is applied onto a stainless substrate by spin coating (step STP1). Then, the stainless steel substrate coated with the poly-imide precursor is set in the furnace (step STP2), and the temperature in the furnace is raised to about 100 ° C. to heat-cure the poly-imide precursor (pre-press).
Bake) (step STP3).

When the poly-imide precursor is cured (semi-cured) to some extent (step STP4), the stainless substrate is taken out of the furnace (step STP5), and the semi-cured poly-imide is exposed and developed, that is, photo-treated.・
Patterning is performed by the lithography method (step S
TP6). After that, the stainless steel substrate on which the poly-imide is patterned is set again in the furnace (step STP
7) The furnace temperature is raised to about 350 ° C. to heat-cure (post-bak) the semi-cured poly-imide (step STP8) to completely imidize the poly-imide (step STP9). An insulating layer is formed through the above steps.

Here, the above-mentioned insulating layer is on the stainless steel substrate,
It is confirmed whether or not it is formed in the three-layer structure of the copper pattern layer and the protective layer (step STP10), and if it is not formed in the three-layer structure, the copper wiring patterning is performed on the insulating layer by the photolithography method. Do (Step STP1
1). By this step, a wiring pattern layer is formed on the insulating layer. Further, the same process as the method for forming the insulating layer is performed (steps STP1 to 9). By this step, a protective layer is formed on the wiring pattern layer. When the stainless steel substrate has a three-layer structure (step STP1
0), etching the stainless steel substrate (step STP
12), the suspension shape is formed, and all processing is completed.

[0008]

During the steps of the above-described conventional method for manufacturing a suspension, the post-baking for forming the insulating layer and the protective layer is usually performed in the atmosphere. However, during this post-baking, the surface of the stainless steel substrate is oxidized to form an oxide film, so that when the stainless steel substrate is subsequently etched into a suspension shape, the shape accuracy may be deteriorated. In order to prevent this oxidation, it is necessary to replace the atmosphere during post-baking with nitrogen or the like and carry out in a non-oxidizing atmosphere.
However, there are drawbacks in that a special apparatus such as a vacuum chamber is required to bring the non-oxidizing atmosphere into a state, and it takes time and effort to draw a vacuum inside the vacuum chamber.

If the step of etching the stainless steel substrate into the suspension shape is performed before the post-baking step, the oxidation of the surface of the stainless steel substrate can be suppressed. However, since the opening of each suspension portion is formed in the stainless steel substrate by the above etching process, there is a problem that the poly-imide precursor cannot be applied to the stainless steel substrate with a uniform thickness by the spin coating method. there were.

In view of the above points, it is an object of the present invention to provide a method of manufacturing a suspension for a magnetic disk device, which is capable of accurately forming a suspension shape and forming an insulating layer or the like having a uniform thickness on the suspension. I am trying.

[0011]

According to the present invention, in the method for manufacturing a suspension for a magnetic disk device, a substrate is formed into the shape of the suspension, and an insulating film is formed on the substrate by a screen printing method. This is achieved by forming a layer and forming a wiring pattern on the insulating layer.

According to the above construction, since the screen printing method is used in the step of forming the insulating layer, the suspension shape can be formed first, and the processing such as patterning becomes unnecessary, so that the suspension shape can be accurately formed. The insulating layer can be molded and can have a uniform thickness on the suspension.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The embodiments described below are preferred specific examples of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. It is not limited to these forms unless otherwise stated.

FIGS. 1A and 1B are plan views showing an internal structure example of a hard disk drive having a suspension manufactured by an embodiment of a method for manufacturing a suspension for a magnetic disk device according to the present invention. It is a side view. A spindle motor 3 and a rotary actuator 4 are arranged on a chassis 2 of the hard disk drive 1. A disk 5 is sandwiched by a clamper 6 on the shaft of the spindle motor 3.

The rotary actuator 4 is provided with a coil 8 and a magnet 9 for rotating the actuator on one side of the rotary shaft 7, and the actuator length is set to a prescribed length on the other side. The arm 10 for is arranged. At the open end of this arm 10, the suspension 1
1 is attached. A slider 12 having a magnetic head is attached to the open end of the suspension 11. The suspension 11 plays a role of pressing the slider 12 against the surface of the disk 5 with a predetermined load.

An operation example of such a configuration will be described. The spindle motor 3 is driven to rotate the disk 5 in the direction of arrow R1 in the figure. Then, the rotary actuator 4 is driven to move the magnetic head to the disk 5
Position on any track above. That is, the coil 8
An electromagnetic force is generated between the magnet 9 and the magnet 9 to rotate the coil 8 in the direction of arrow R2 in the figure, and the arm 10, the suspension 11, and the slider 12 which are integrated together are rotated in the direction of arrow R3 in the figure. And disk 5
Signals are read and written by a magnetic head positioned on an arbitrary track above.

FIG. 2 is a flow chart showing an embodiment of a method of manufacturing a suspension for a magnetic disk device according to the present invention. The stainless steel substrate is etched (step STP21) to form a suspension shape. A poly-imide precursor is applied onto a stainless steel substrate formed into a suspension shape by a screen printing method (step STP22). Then, the stainless steel substrate coated with the poly-imide precursor is set in the furnace (step ST
P23), the furnace temperature is raised to about 350 ° C. to heat-cure (post-bak) the poly-imide precursor (step STP24), and the poly-imide is completely imidized (step STP25). An insulating layer is formed through the above steps.

Here, it is confirmed whether or not the three-layer structure of the insulating layer, the wiring pattern layer, and the protective layer is formed on the stainless steel substrate (step STP26). If the three-layer structure is not formed yet, the photo is performed. -Copper wiring patterning is performed on the insulating layer by the lithography method (step STP2
7). By this step, a wiring pattern layer is formed on the insulating layer. Further, the same process as the method for forming the insulating layer is performed (steps STP21 to 25). By this step, a protective layer is formed on the copper pattern layer. Then, when the three-layer structure is formed on the stainless steel substrate (step STP2
6), all processing is completed.

The suspension 11 thus manufactured has a structure as shown in the perspective view of FIG. 3, for example.
That is, the insulating layer and the protective layer are formed on the surface of the suspension 11 excluding the C-shaped blank portion at one end of the rectangular suspension 11 as shown in the figure. The wiring pattern layer is formed from the inside of the blank portion to the other end of the suspension 11 through the opening and the peripheral portion. Therefore, the slider 12 is mounted inside the blank portion, and the terminal of the slider 12 and one end of the wiring pattern layer are connected.

The poly-imide precursor to be applied on the stainless steel substrate formed into a suspension shape by the above-mentioned screen printing method is a poly-imide precursor which is dissolved at the time of heating and curing after printing and is further compatible with the binder to form a film. -A paste-like polyimide having thixotropic properties, which is composed of a mixed solvent composed of a filler of imide fine particles, a soluble poly-imide binder, and two kinds of solvents having different solubilities and drying properties (for example, product name PIQ-P100 Hitachi Chemical Co., Ltd. is used.

Screen printing is performed under the following conditions, for example. As the screen, a screen made of an amorphous alloy, a mesh number of 200, a mask of three-dimensional cured acrylic resin, and a stencil thickness of 72 μm is used. As a squeegee, the material is silicone rubber,
A mold having a square shape and a Shore hardness of 80 is used.
The printing machine is driven with a clearance of 1.5 mm, a squeegee pressure of 0.2 MPa, a squeegee speed of 100 m / s, and a scraper speed of 100 m / s.

In the above embodiment, the insulating layer and the protective layer are made of poly-imide. However, the present invention is not limited to this, and the insulating layer is an insulator and the screen printing method is used. Applicable materials such as a polymer film such as a resist may be formed, and the protective layer may be formed by gold plating or the like. Further, the protective layer itself may not be formed.

[0023]

As described above, according to the present invention,
The suspension shape can be accurately formed without forming a special device such as a vacuum chamber, and an insulating layer or the like having a uniform thickness can be formed on the suspension, so that a significant cost reduction can be achieved.

[Brief description of the drawings]

FIG. 1 is a plan view and a side view showing an internal structure example of a hard disk drive including a suspension manufactured by an embodiment of a method for manufacturing a suspension for a magnetic disk device according to the present invention.

FIG. 2 is a flowchart showing an embodiment of a method for manufacturing a suspension for a magnetic disk device according to the present invention.

FIG. 3 is a perspective view showing an example of a suspension manufactured by an embodiment of a method of manufacturing a suspension for a magnetic disk device according to the present invention.

4 is a cross-sectional perspective view of the suspension shown in FIG. 3, taken along the line AA.

FIG. 5 is a perspective view showing an example of a conventional suspension.

FIG. 6 is a flowchart showing an example of a conventional method for manufacturing a suspension for a magnetic disk device.

[Explanation of symbols]

 1 Hard Disk Drive 2 Chassis 3 Spindle Motor 4 Rotating Actuator 5 Disk 6 Clamper 7 Rotating Shaft 8 Coil 9 Magnet 10 Arm 11 Suspension 12 Slider

Claims (2)

[Claims] 1. A method for manufacturing a suspension for a magnetic disk device, wherein a substrate is formed into the shape of the suspension, an insulating layer is formed on the substrate by a screen printing method, and a wiring pattern is formed on the insulating layer. A method of manufacturing a suspension for a magnetic disk device, comprising: 2. The method for manufacturing a suspension for a magnetic disk device according to claim 1, wherein a protective layer is formed on the wiring pattern by the screen printing method.