JPH08321009A - Method for working magnetic head - Google Patents

Abstract

PURPOSE: To form the throat height of a magnetic head element with high accuracy over the entire part of solder by cutting the solder with good straightness. CONSTITUTION: Voltage is impressed between a wire 44 and a wafer 10 by a power source 48. The wire 44 is delivered at a specified speed from a delivery reel 46 and while the wire is taken up by a take-up reel 48, a table is driven to transfer the wafer 10 at a specified speed in an arrow X direction. The wire 44 successively cuts the wafer 10 along the arranging direction of a thin- film magnetic head 12 while maintaining a discharge gap (g) between the wire and the wafer 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing a floating thin-film magnetic head used in a fixed disk device, etc. It is designed to be able to cut the row with good straightness when producing the row.

[0002]

2. Description of the Related Art An example of a manufacturing process of a floating thin film magnetic head for a fixed disk device will be described with reference to FIGS. (1) Wafer Process A large number of thin film magnetic head elements 12 are formed on the wafer 10 as magnetic head elements in the vertical and horizontal directions.

(2) Cutting into Rows The wafer 10 is cut into rows 14. A plurality of magnetic head elements 12 are arranged in a row on one row 14. ABS (Air Bearin) with one side of the cut surface facing the recording medium
g Surface) Configure the surface 28.

(3) ABS surface lapping One row plate 20 of a lapping machine holds a row 14 with its ABS surface 16 facing upward, and an abrasive grain 24 is provided between the platens 18 and 20.
Is put and pressed, and the ABS surface 16 is lapped on one side by rubbing.

(4) Rail formation A groove 26 is formed on the ABS 16 to form a rail 28. The tip surface of the pole portion 30 of the thin film magnetic head element 12 is flush with the ABS surface 16, and the throat height (the length of the pole portion 30) h is the same as the ABS obtained in the step (3).
It is formed into a predetermined length by surface rubbing.

(5) Cutting into sliders The row 16 is cut into individual sliders 31 to complete the thin film magnetic head 32.

In the above process, the wafer 10 of (2)
Conventionally, the step of cutting the row 14 into rows 14 is performed by cutting the wafer 10 with a diamond blade 36 using a slicing machine 34 to form the rows 14 as shown in FIG. 4, or as shown in FIG. As described above, by using the wire cutting machine 38, the wire 40 is pulled on the wafer 10 coated with the polishing material 42 to cut the wafer 10 to form the row 14.

[0008]

A large number of thin film magnetic head elements 12 are formed on the row 14 cut from the wafer 10. Since the throat height h of each element 12 has a great influence on the electromagnetic conversion characteristics, it is required that the rows 14 as a whole have a highly accurate dimension without variation. Therefore, the cut row 14 requires high straightness without bending.

However, the wafer 1 according to FIGS.
In the cutting method of 0, since the stress applied to the wafer 10 at the time of cutting was large, the row 14 was cut in a bent state as shown in FIG. 6A, and the straightness of the row 14 was poor. And
In the step (3), the curved surface 14 and 20 are pressed against the row 14 bent in this way, and the ABS surface 16 is ground while the curve is corrected, so that the throat height h Was not constant in the entire row 14, the quality was poor, and the yield was low.

The present invention solves the above-mentioned problems in the prior art, and cuts the rows with good straightness so that the throat height of the magnetic head element can be formed with high accuracy over the entire row. Is to provide.

[0011]

According to the present invention, a row is manufactured by cutting a substrate in which a large number of magnetic head elements are arranged in the vertical and horizontal directions in one direction by wire cut electric discharge machining.

[0012]

When the wire-cut electric discharge machining is used to cut the substrate, the wires that are electrodes cut the substrate in a non-contact manner while maintaining a discharge gap between the electrode and the substrate. Therefore, the slicing machine 34 shown in FIG. Wire cutting machine 3
As in No. 8, cutting pressure is not applied to the processed surface, and cutting can be performed with almost no processing stress. Therefore, the cut rows can be obtained with high straightness and without warpage, and a high quality and high yield magnetic head with a uniform throat height value can be obtained.

[0013]

FIG. 1 shows an embodiment of the present invention. The wafer 10 constituting the substrate is a sintered material composed of TiC and Al ₂ O ₃ (Al ₂ O ₃ is a non-conductive material, but since it is dispersed in TiC, it shows conductivity when viewed as a whole substrate. , Wire can be cut.) And the like. A large number of thin film magnetic head elements 12 are formed on the wafer 10 in the vertical and horizontal directions by a wafer process. The surface of the wafer 10 has a magnetic head element 1
It is covered with a protective film 13 for the purpose of protecting 2. Protective film 1
Since 3 is composed of a non-conductive film such as alumina, it hinders wire-cut electric discharge machining. Therefore, before cutting the wire, the protective film 13 is removed by grooving along the line to be cut with a diamond blade or the like.
To form. The groove 15 also helps prevent chipping (chipping) of the protective film 13 during lapping in a later process (FIG. 8B).

The wafer 10 is held on a transfer table (not shown) and is transferred by a motor in one direction X in which the elements 12 are arranged (a direction along a row to be formed). The wire 44 for wire-cut electric discharge machining is arranged substantially perpendicular to the surface of the wafer 10. Wire 44 is sending reel 4
It is sent out at a constant speed from 6 and wound on the take-up reel 48. At this time, the wire 44 is kept in a tensioned state with a constant tension. A power supply 48 is connected between the wafer 10 and the wire 44.

In the above structure, when the wafer 10 is cut to form the row 14, the table is moved in the X and Y directions to position the wire 44 at the starting point of the cutting position of the first row of the wafer 10. The power source 48 to the wire 44
The wire 4 while voltage is applied between the wafer 4 and the wafer 10.
4 is sent out from the reel 46 at a constant speed and wound by the take-up reel 48, the table is driven to transfer the wafer 10 in the direction of the arrow X at a constant speed to cut the wafer 10 from one end to the other. When the cutting of the first row is completed, the second row, the third row, and so on are sequentially cut.

The state at the time of cutting is shown in a plan view in FIG. The wire 44 cuts the wafer 10 along the arrangement direction of the thin-film magnetic heads 12 while maintaining the discharge gap g with the wafer 10. Therefore, there is almost no processing stress on the wafer 10 at the time of cutting, and the cut row 14 has extremely high straightness as shown in FIG. 8A. Therefore, the cut row 14 is (b)
When the ABS surface 16 is ground by being sandwiched between the surface plates 18 and 20 of the lapping device as described above, the throat height h becomes low 1.
4 is obtained uniformly, and a thin film magnetic head of good quality and high yield can be obtained.

FIG. 9 shows an example (in the case of horizontal cutting) of holding the wafer 10 on the transfer table without hindering the wire cutting. Margins 10a and 10b on which magnetic head elements are not formed are provided on two sides of the peripheral edge of the wafer 10, and mounting brackets 17 and 19 are attached thereto with adhesive or the like. Grooves 15 are formed in advance on the surface of the wafer 10 along the line for cutting the wire. Further, a groove 21 is also formed at the boundary with the blank portion 10a. By attaching the mounting brackets 17 and 19 to the metal jig 25 with the screws 23,
The wafer 10 is fixed to the metal jig 25. At this time,
The side surface of the wafer 10 is brought into contact with the metal jig 25 to be in a conductive state. By chucking the metal jig 25 on the transfer table, the wafer 10 can be held on the transfer table without hindering wire cutting. Wafer 1
0 is connected to one polarity of the power source through the metal jig 25. First, wire cut along the groove 15,
When wire cutting is completed for all grooves 15, groove 2
1 is wire-cut and separated into each row 14.

Another example of the method for holding the wafer 10 on the transfer table (in the case of vertical cutting) is shown in FIG. A margin 10c where no magnetic head element is formed is provided on one side of the peripheral edge of the wafer 10, and a mounting bracket 27 is attached thereto with an adhesive, a screw, or the like. Grooves 15 are formed in advance on the surface of the wafer 10 along the line for cutting the wire. The wafer 10 is fixed to the metal jig 31 by attaching the mounting bracket 27 to the metal jig 31 with the screws 29. At this time, the side surface of the wafer 10 contacts the metal jig 31,
It becomes conductive. By chucking the metal jig 31 on the transfer table, the wafer 10 can be held on the transfer table without hindering wire cutting.
The wafer 10 is connected to one polarity of the power source through the metal jig 31. The wire cutting is first performed along the groove 15 to separate each row 14.

[0019]

Other Embodiments In the above embodiment, the position of the wire 44 is fixed and the wafer 10 is transferred in the X direction for cutting, but the wafer 10 may be fixed and the wire 44 may be transferred in the X direction for cutting. it can.

Further, in the above embodiment, the wire 44 is arranged perpendicular to the surface of the wafer 10, but as shown in FIG. 11, the wire 44 is arranged parallel to the surface of the wafer 10 along the cutting line and cut. You can also do it. In this case, the wire 44 or the wafer 10 is transferred and cut in the direction Z perpendicular to the surface of the wafer 10. Further, as shown in FIG. 12, the wire 44 is obliquely arranged on the wafer 10 along a line for cutting,
The wire 44 or the wafer 10 can be transferred in the X direction and cut. Furthermore, a plurality of wires 14 may be used to separate a plurality of rows 14 from the wafer 10 at once in the same step.

[0021]

As described above, according to the present invention, the wire-cut electric discharge machining is used to cut the substrate, and the electrode is cut in a non-contact manner while maintaining a discharge gap between the wire and the substrate. By doing so, it is possible to avoid the cutting pressure from being applied to the processing surface, and it is possible to cut with almost no processing stress. Therefore, the cut rows can be obtained with high straightness and without warpage, and a high quality and high yield magnetic head with a uniform throat height value can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a process drawing showing an example of a manufacturing process of a floating thin-film magnetic head for a fixed disk device.

FIG. 3 is a process diagram showing the continuation of FIG. 2;

FIG. 4 is a diagram showing an example of a conventional wafer cutting method.

FIG. 5 is a diagram showing another example of a conventional wafer cutting method.

FIG. 6 is a diagram showing a state in which the throat height is unevenly processed when lapping the ABS surface in a state where the row is bent and cut.

FIG. 7 is a plan view showing how the wafer is cut by the wire-cut electric discharge machining shown in FIG. 1 to form rows.

FIG. 8 is a diagram showing a state in which the ABS surface of a row cut by the processing method of the present invention is lapped.

FIG. 9 is a diagram showing an example of a method of holding the wafer 10 on a transfer table without hindering wire cutting.

FIG. 10 is a diagram showing another example of a method of holding the wafer 10 on the transfer table without hindering the wire cutting.

FIG. 11 is a diagram showing another embodiment of the present invention.

FIG. 12 is a diagram showing still another embodiment of the present invention.

[Explanation of symbols]

 10 Wafer (Substrate) 12 Thin Film Magnetic Head Element (Magnetic Head Element) 14 Low 32 Thin Film Magnetic Head (Magnetic Head)

Claims (1)

[Claims] 1. A method of processing a magnetic head, comprising forming a row by cutting a substrate in which a large number of magnetic head elements are arranged in a vertical direction and a horizontal direction in one direction by wire cut electric discharge machining.