JPH1055506A - Magnetic head as well as its production and apparatus for production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic head of a low cost having a narrow track width as well as a process for producing the same and an apparatus for production thereof. SOLUTION: A device capable of forming ion beams for reduction projecting a mask having patterns of a pair of grooves in working a pair of grooves 6, 7 to determine the track width of head magnetic poles 11, 12 of the magnetic head is manufactured. The processing to narrow the track of the magnetic head is executed by irradiation with such projecting ion beams. If these projecting ion beams are used, the central parts of the beams are capable of executing processing with high accuracy and the entire ion beam current may be made larger by >=1 digits as compared with the converged ion beam capable of providing the same accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head used for magnetic recording and a method and an apparatus for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, Japanese Patent Application Laid-Open No. 3-296907 is known as a method for making the track width of a magnetic head finer (narrower track) in order to increase the density of magnetic recording.
In this conventional example, a pair of grooves is formed by sputtering on a sliding surface of a magnetic head by irradiating a focused ion beam having a beam diameter of sub μm, and the grooves define the track width of the magnetic head. This method has a simple process because of direct processing, and has excellent fineness and controllability.

[0003]

However, in the above conventional method, the current of the focused ion beam must be reduced for fine processing, and there is a problem that the throughput is low. That is, to apply this to a production line, the throughput is significantly insufficient with respect to the allowable production cost.

An object of the present invention is to provide a low-cost magnetic head having a narrow track width, and a method and an apparatus for manufacturing the same.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to collectively process two substantially symmetrically arranged grooves provided on a part of a sliding surface with a medium in a magnetic head by using an ion beam for reducing and projecting a mask. Is achieved by

The above-mentioned object is achieved by processing at least one groove provided in a part of a sliding surface of a magnetic head with a medium by an ion beam for projecting a mask in a reduced size. In a preferred embodiment of the present invention, these grooves are filled with a non-magnetic substance.

In the groove processing for narrowing the track of the magnetic head, high precision is required for the inner peripheral portions of a pair of grooves for determining the track width, but the shape of the outer peripheral portions of the grooves is not so limited. Focusing on this point, the present invention applies a focused ion beam apparatus to create an apparatus for forming an ion beam for reducing and projecting the mask having the pair of groove patterns, and irradiating the projected ion beam. The magnetic head is made to have a narrow track.

When the projected ion beam is used, the central portion of the pair of grooves for determining the track width becomes the central portion of the beam, so that the focused portion can be processed with high precision and can produce the same precision. In comparison, the total ion beam current can be increased by one digit or more.

In general, it is known that a projected ion beam has a lower current density than a focused ion beam, but can collectively irradiate a pattern in a wide area with high resolution. However, in the case of the projected ion beam, the peripheral distortion of the pattern is large and the current density is not uniform. Although such characteristics seem at first glance to be inconvenient, the present invention has discovered that the above disadvantages can be utilized as advantages when the projected ion beam is used for narrow track processing of a magnetic head. That is, the basic knowledge of the present invention is that, by limiting the collective irradiation area of the projection ion beam to a size of several μm, a projection ion beam having a higher edge resolution and a higher beam current than a focused ion beam is formed. It has been found that it is possible to set design conditions of a device that can be used.

When a pair of grooves having a size of several .mu.m are formed in order to reduce the track width of the magnetic head, a high accuracy of the order of 0.1 .mu.m is required for a part of the side of the groove which determines the track width. Is done. At this point, the projected ion beam satisfies the necessary conditions because the distortion at the center is about 10 nm, which is almost negligible. On the other hand, the peripheral portion of the groove has a purpose of reducing the leakage of the magnetic field from the magnetic pole by being dug, so it is better to dug deeper. The above projected ion beam naturally satisfies this condition. Although the shape distortion around the groove is hardly a problem, it can be solved by precisely controlling the processing shape of the magnetic pole by deforming the pattern shape of the mask projected by the ions in the direction opposite to the distortion in advance.

[0011]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

Embodiment 1 FIG. 1 is a perspective view showing a recording / reproducing separation type thin film magnetic head during sputtering by irradiation of a projected ion beam from a sliding surface side as a first embodiment of the present invention. . In this magnetic head, a reproducing head 2, a recording head 3, and a protective layer 4 made of alumina are sequentially laminated on a slider base 1 made of alumina titanium carbide, and this is cut.
The cut surface is made by polishing. This cut surface is the sliding surface. The recording head 1 includes two permalloy magnetic poles 11 and 12 opposed to each other via a gap layer 10 made of alumina. The coils surrounding the magnetic poles 11, 12 are not visible because they are inside. The reproducing head 2 has a magnetoresistive element 20 connected to copper electrodes 21 and 22 sandwiched between permalloy magnetic shield layers 23 and 24 via an alumina insulating layer. The lower magnetic pole 12 also serves as the upper magnetic shield layer 23. The track width before processing with the projection ion beam is 10 μm for the recording head 3 and 3 μm for the reproducing head 2.

In the magnetic head shown in FIG. 1, two rectangular grooves 6 and 7 having a size of 10 μm square and a depth of 2 μm are formed on the basis of the center of the reproducing head 2 by sputtering with irradiation of the projected ion beam 100. I have. Thus, the track widths of the recording head and the reproducing head are defined by the convex portions 5 and both are 2 μm. The ion species of the projection ion beam 100 used for the processing is Ga, and the blur of the edge of the processing pattern when the acceleration voltage is set to 30 kV and the beam current is set to 15 nA is 0.05 μm. The time required for the groove processing in FIG. 1 is about 30 seconds. This is 15 times the processing speed and 2 times the processing resolution as compared with the case of processing with a Ga focused ion beam having a beam diameter of 0.1 μm and a beam current of 1 nA, and the difference in the sputtering rate for each material is reduced. More flat processing.

FIG. 1 shows a first embodiment of the present invention.
According to the processing method of (1), the track width of the recording / reproducing separation type thin film magnetic head can be narrowed with a high throughput, and the center of the reproducing head and the center of the recording head can be accurately aligned. Further, since the edge of the narrowly processed head is sharp, there is an effect that the leakage magnetic field can be reduced. By changing the opening shape of the mask used for forming the projected ion beam,
It is obvious that the track widths of the reproducing head and the recording head can be changed.

FIG. 1 shows an example in which both the magnetic pole of the recording head and the magnetic shield of the reproducing head are processed.
The processing of only the magnetic pole has the effect of reducing the track width.
Further, it is obvious that the magnetic pole can be trimmed in the direction perpendicular to the track width by changing the opening shape of the mask.

Since alumina titanium carbide, which is the slider base of the head used in the embodiment, is a non-conductive material, the sample can be charged up during the ion beam processing, and the grooves can be formed with high precision. There was a view that it would disappear, but there was no particular problem in actual processing. This is probably because the ion beam has good symmetry and the permalloy magnetic pole discharges the charge.
When processing with higher precision than in the embodiment of FIG. 1, charging is neutralized by electron irradiation, or A
It is desirable to take measures such as discharging a charge by attaching a u-deposited layer.

Embodiment 2 Next, a magnetic head processing apparatus of the present invention used in the processing method shown in FIG. 1 will be described.

FIG. 2 is a perspective view showing the overall configuration of the magnetic head processing apparatus of the present invention used for processing the magnetic head of FIG. The main part of this apparatus is a projection ion beam optical system 2
00, sample holder 210, sample stage 211, laser length measuring device 212, laser microscope camera 220, gas source 23
0, and most of them are arranged inside a high vacuum vessel (not shown). The circuits for controlling these are a position detection controller 241, an ion beam controller 24
2, stage controller 243, length measurement controller 2
44, a gas source controller 245, and a control circuit 240 for controlling these components. The magnetic heads as samples are connected in an array, and they are bundled and fixed to the sample holder 210 with electrowax.

Here, the procedure of narrow track processing of the magnetic head will be described. First, the center positions of all the reproducing heads on the magnetic head array are measured in advance with an accuracy of 0.05 μm. For this purpose, the control circuit 240 gives the position data of the magnetic head to the stage controller 243 in advance and moves the sample stage 211, where the sample image is taken in by the laser microscope camera 220 and sent to the position detection controller 241. The position detection controller 241 reads the deviation of the center position of the reproducing head from the sample image and sends it to the control circuit 240. The control circuit 240
The position shift, the stage position coordinates measured by the laser length measuring device 212, and the predetermined offset of the center position of the reproducing head and the center of the processing pattern are added and stored in the internal memory allocated to each magnetic head. As described above, the sample stage 211 is moved based on the measured stage coordinates of the center of all the read heads, and an arbitrary magnetic head is placed immediately below the projection ion beam optical system 200 to project the projected ion beam. And process it. Here, the control circuit 240 gives information on the positional deviation between the center of the projected ion beam and the center of each magnetic head to the ion beam controller 242, and corrects the irradiation position of the projected ion beam.

A feature of the present invention is that high-throughput processing can be performed by the projection ion beam optical system 200. FIG. 3 shows the internal configuration.

An ion beam 202 emitted from a Ga liquid metal ion source 201 is converged by an irradiation lens system 203, that is, an electrostatic lens (composite lens of an acceleration lens and an Einzel lens) composed of four axially symmetric electrodes. Then, the mask 204 is irradiated. Here, the irradiation lens system 203 is adjusted so as to accelerate the ion beam 202 to an acceleration voltage of 30 kV and converge on the center of the projection lens 206. Of the ion beam 202, the ion beam 100 transmitted through the opening 205 of the mask 204 is irradiated on the sample by the projection lens 206, that is, an electrostatic lens (Einzel lens) composed of three axially symmetric electrodes.

Here, the projection lens 206 is
The pattern No. 4 is adjusted so as to be reduced and projected onto the sample 207 at a magnification of 1/10. An electrostatic deflector (not shown) is provided below the projection lens 206, and the irradiation position of the ion beam 100 on the sample 207 is set to 50 μm.
You can move within the range. Also, on the projection lens 206,
A blanking deflector (not shown) is provided to turn on the irradiation of the projection ion beam 100 on the sample 207,
Toggle off.

The beam current of the projection ion beam 100 used for processing is 15 nA, and the blur of the edge of the processing pattern is 0.05 μm. Processing position setting accuracy is 0.05μ
m. The time required for the groove processing in FIG. 1 is about 30 seconds. When chlorine gas was blown from the gas source 230 when irradiating the magnetic head with the projected ion beam, the magnetic pole and the magnetic shield were processed twice as fast, and the processing time was about 15 seconds.

As described above, according to the embodiments of FIGS. 2 and 3,
There is an effect that the processing for narrowing the track width of the magnetic head can be performed with high accuracy by accurately positioning.

In this embodiment, the center positions of the magnetic heads are read one by one. However, if the arrangement accuracy of each magnetic head in the magnetic head array is sufficiently high, only the center positions of at least two magnetic heads are read. But it is good. Also,
Instead of reading the position of the magnetic head itself, reading the positions of two or more position detection marks provided on the magnetic head array in advance can be used instead.

Further, in this embodiment, the position of the magnetic head is read using a laser beam. However, if attention is paid to damage due to charging, the position of the magnetic head can be read using an electron beam or an ion beam. The task is achieved. For such an ion beam, the mask 204 in the projection ion beam optical system 200 of the present embodiment is changed to a circular aperture stop, and the intensity of the lens system is reset to form a focused ion beam. Is also possible.

In this embodiment, the magnetic pole of the magnetic head is processed by the projected ion beam from the sliding surface of the magnetic head. However, before the magnetic head is manufactured (the magnetic pole is attached to the wafer-like slider base). It is also possible to perform processing by a projected ion beam from a direction perpendicular to the lamination surface of the magnetic poles in the laminated state). In this case, it is necessary to increase the processing volume of the magnetic pole portion in consideration of the margin at the time of cutting each magnetic head, so that the throughput is slightly lowered, but the same effect as that of the present embodiment can be obtained.

Embodiment 3 FIG. 4 shows an example in which a recording / reproducing separation type thin film magnetic head sputtered by projection ion beam irradiation is further processed as a second embodiment of the present invention. FIG. 2 is a perspective view of the thin-film magnetic head as viewed from a sliding surface side. The configuration of the projection ion beam apparatus used for this processing may be the same as that already shown in FIGS.
In this processing, while irradiating the magnetic head with the projection ion beam 100, several kinds of deposition gases 101 are switched and irradiated.

A feature of the present embodiment is that, in the same projection ion beam apparatus, a magnetic shield forming process for preventing a leakage magnetic field is performed, following the process for reducing the track width of the magnetic head. After grooving, first use CO gas 101
Is irradiated with the projected ion beam 100 to form an insulating C film in the grooves 6 ′ and 7 ′. Thereafter, the gas 101 is transferred to Cu (hfac) TMVS (copper
(Hexafluoroacetylacetonate / trimethylvinylsilane) to form a Cu film with good conductivity. Each processing time is about 2 seconds and about 5 seconds.

The C film prevents the magnetoresistive element 20 from being short-circuited through the magnetic poles 11 and 12. When the sample was heated to about 100 ° C. with an infrared lamp during the formation of the Cu film, the conductivity of the film was made close to that of bulk Cu. With this highly conductive Cu film, when the recording head was operated at a high frequency of 20 MHz or more, the leakage magnetic field from portions other than the projections of the head could be cut off by 90% or more.

As described above, according to the embodiment shown in FIG. 4, a magnetic head having a narrow track width and a small leakage magnetic field in a high frequency region can be manufactured in the same apparatus, so that the process is simplified and the cost is reduced.

Example 4 FIG. 5 is a perspective view showing a configuration of a main body of a magnetic head processing apparatus used in a manufacturing method according to a second embodiment. Most of this apparatus is the same as the apparatus of the second embodiment, except that the irradiation lens system 203 'is off-axis. The irradiation lens system 203 'is composed of an electrostatic lens (acceleration lens) composed of two axially symmetric electrodes and a two-stage quadrupole lens. By using the two-stage quadrupole lens, the second embodiment
In the same manner as described above, the ion beam 202 ′
The shape of the ion beam on the mask 204 can be changed from a circle to an ellipse under the condition of focusing on the center of the ion beam.

The feature of the embodiment shown in FIG. 5 is that the mask 2 is formed by using the non-axisymmetric illumination lens system 203 '.
That is, it is possible to irradiate the ion beam with the non-axisymmetric hole pattern 205 on the substrate 04. As compared with the apparatus of Example 1, the sample 207 was irradiated with about twice the ion current for the same processing pattern.

As described above, according to the fourth embodiment, in processing for reducing the track width of a magnetic head, there is an effect that a high throughput can be obtained by using an ion beam efficiently.

Embodiment 5 FIG. 6A is a perspective view of a magnetic head of the present invention after grooves have been formed by a projected ion beam. In this embodiment,
Only a part of the upper recording head magnetic pole 11 and the lower recording head magnetic pole 12 is processed, and the reproducing head is not processed. Thus, damage to the magnetoresistive element 20 due to ion irradiation is avoided. The depth of the grooves 6, 7 is about 1.0 μm. FIG. 6A is a vertical sectional view of the magnetic head of FIG.
(B). The structure of the AA ′ section is the same as before the groove processing. The magnetic field generated by the current flowing through the coil 13 passes through the inside of the magnetic poles 11 and 12 and leaks outside at the end of the gap layer 10. Information is recorded on a medium (not shown) by the leakage magnetic field.

Sliding surface recesses 6, 7 formed by groove processing
In this case, since the recording magnetic poles 11 and 12 recede, the sliding surface convex portion 5
The magnetic field concentrates between the recording magnetic poles 11 and 12. That is, a narrow track width can be achieved. FIG. 7A is a front view of the magnetic head of the present invention after the groove is processed by the projected ion beam on the sliding surface side. The size of one groove is 3μ in length
m, 2 μm in width, and the interval between the two grooves is 1 μm. FIG.
(B) shows a cross-sectional view of the magnetic head taken along line BB '.
The edge of the groove processed by the projection ion beam has only a blur of about 10 nm, and the side walls 6-1 and 7- of the recess 5 of the magnetic pole 11 are formed.
Although 1 has an angle of about 80 degrees that can be spontaneously formed by sputtering, it has very high precision. Therefore, in the present magnetic head, the track width T is set to 1.0 μm with an accuracy of 0.1 μm or less.
I was able to. Here, the current of the projection ion beam used for processing is 50 nA, and the current density is close to 400 mA / cm ² . The processing time was about 3.5 seconds. Since an inward strain of 0.1 μm to 0.2 μm was generated around the processing pattern, the beam current density increased toward the outside 6-2, 7-2 of the grooves 6, 7 to increase the current density of the beam 6-2, 7-. In No. 2, it was dug about 0.2 μm deep. However, the magnetic characteristics of the present magnetic head hardly changed depending on the distribution of the groove depth.

Here, the magnetic head of the present invention will be compared with a magnetic head in which similar processing is performed using a focused ion beam. FIG. 8A shows a front view of the sliding surface side of the magnetic head processed by the focused ion beam. First, a thick beam with a large current (a beam diameter of 1 μm at a current of 10 nA)
Processing of grooves 6 and 7 was performed in m). FIG. 8B shows a BB ′ cross section at this time. The track width T is not clear due to a blur of about 1 μm at the edge of the processing area. Actually, since the magnetic field concentration on the magnetic pole protrusions 5 is not sufficient, the effective track width is larger than 1 μm. Therefore, the grooves 8 and 9 in FIG. 8A were additionally processed on both sides of the magnetic pole protrusion 5 with a thinner beam (beam diameter 0.1 μm at a current of 1 nA). As a result, a magnetic pole having a clear track width T as shown in FIG. As described above, a magnetic pole having a narrow track width can be formed by a focused ion beam, but the throughput is low because processing is performed with an ion beam having a small current. Further, even if the magnetic pole 5 having a narrow track width is formed, deep grooves 8-1 and 9-1 are formed on both sides thereof. The magnetic field strength for recording decreases. Therefore, in the magnetic head of the present invention, the lateral leakage magnetic field can be reduced and the track width can be reduced.

In the magnetic head of the present invention, a protective film of diamond-like carbon can be formed on the entire sliding surface immediately after the formation of the groove in order to prevent the magnetoresistive element 20 from being electrically broken. However, when the groove of the reproducing head is not processed as in the present embodiment, it is possible to form the protective film first and then process the groove.

[0039]

According to the present invention, a magnetic head corresponding to a fine track width can be provided at a practical cost, so that a magnetic disk device equipped with the magnetic head can have a large storage capacity and a low cost. There is.

[Brief description of the drawings]

FIG. 1 is a perspective view of a magnetic pole portion of a magnetic head showing a manufacturing method according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a magnetic head processing apparatus used in the manufacturing method according to the first embodiment of the present invention.

FIG. 3 is a perspective view of a projection ion beam optical system of the magnetic head processing apparatus of FIG. 2;

FIG. 4 is a perspective view of a magnetic pole portion of a magnetic head showing a manufacturing method according to a second embodiment of the present invention.

FIG. 5 is a perspective view showing another embodiment of the projection ion beam optical system of the magnetic head processing apparatus of the present invention.

FIGS. 6A and 6B are a perspective view and a longitudinal sectional view, respectively, of the magnetic head of the present invention after being processed by a projected ion beam.

FIGS. 7A and 7B are a top view (a) and a cross-sectional view (b) of the sliding surface side of the magnetic head of the present invention after processing with a projection ion beam.

FIG. 8 is a top view (a) and cross-sectional views (b) and (c) of the sliding surface side of the magnetic head after being processed by the focused ion beam.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Slider base, 2 ... Reproduction head, 3 ... Recording head, 4 ... Protective layer, 5 ... Sliding surface convex part, 6, 6 ', 7,
7 ', 8, 8', 9, 9 ': concave surface of sliding surface, 10: gap layer, 11: upper recording head magnetic pole, 12: lower recording head magnetic pole (also serves as shield layer), 13: coil, 20: magnetic resistance Element, 21, 22: electrode, 23: upper magnetic shield layer, 24: lower magnetic shield layer, 100: projected ion beam, 101: deposition gas, 200: projected ion beam optical system, 201: liquid metal ion source, 202 ... Ion beam, 203, 203 '... Irradiation lens system, 204 ... Mask, 205 ... Opening of mask, 206 ... Projection lens, 20
7: sample, 210: sample holder, 211: sample stage, 212: laser measuring instrument, 220: laser microscope camera, 230: gas source, 231: reactive gas, 240: control circuit, 241: position detection controller, 242 ... Ion beam controller, 243 ... Stage controller, 244 ... Length measurement controller, 245 ... Gas source controller, 246 ... Monitor

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yuichi Madokoro 1-280, Higashi-Koigabo, Kokubunji-shi, Tokyo Inside the Hitachi, Ltd. Central Research Laboratory, Hitachi, Ltd.

Claims (11)

[Claims] In a magnetic head for recording and reproducing magnetic information on and from a magnetic recording medium, one or more grooves are provided on a part of a sliding surface of the magnetic head with the medium. A magnetic head characterized in that the grooves are processed by irradiating an ion beam for projecting the mask in a reduced size. 2. The magnetic head according to claim 1, wherein a track width of the head magnetic pole is defined by an interval between a pair of grooves provided on the sliding surface. 3. The magnetic device according to claim 1, wherein the groove is formed by irradiating at least one of an etching gas and a deposition gas simultaneously with the irradiation of the ion beam. head. 4. The method according to claim 1, wherein a part or all of the groove is filled with a non-magnetic material, and the non-magnetic material is formed by irradiating a deposition gas simultaneously with the ion beam irradiation. The magnetic head according to claim 1. 5. The magnetic head according to claim 1, wherein said magnetic head is a recording / reproducing separation type thin film magnetic head, and said groove is machined with reference to a center position of said reproducing head.
The magnetic head according to any one of the above. 6. A magnetoresistive reproducing head comprising a thin film having a magnetoresistive effect and soft magnetic members sandwiching a thin film having a magnetoresistive effect on both sides via an insulating layer on a substrate serving as a base constituting the magnetic head. Forming an inductive recording head comprising a magnetic pole and a conductive pattern interlinking with the magnetic pole; and (2) cutting the substrate on which the two heads are laminated into a desired shape to obtain a medium facing surface. And (3) detecting the center position of the reproducing head exposed on the medium facing surface, and then reducing and projecting the mask onto the cross section based on the center position. Irradiating an ion beam to form a recess in a part of the cross section including the components of the recording head, and forming components of the two heads sandwiched between the recesses. Production method. 7. A means for forming an ion beam for reducing and projecting a pattern on a mask, a means for detecting a characteristic position on a sliding surface of a magnetic head with a medium, and an arbitrary means based on the characteristic position of the magnetic head. Means for irradiating the position with the ion beam. 8. An apparatus according to claim 7, further comprising means for blowing at least one of an etching gas and a deposition gas onto said magnetic head. 9. A mask for forming an ion beam for reducing and projecting the mask pattern, comprising: a liquid metal ion source or a plasma ion source; an irradiation lens system; a mask having a non-axisymmetric aperture pattern; 8. The magnetic head manufacturing apparatus according to claim 7, comprising a projection lens system and a deflector. 10. An apparatus according to claim 9, wherein said irradiation lens system is non-axially symmetric. 11. A magnetic head for recording and reproducing magnetic information on and from a magnetic recording medium, wherein a pair of grooves defining a track width of a head magnetic pole are formed in a part of a sliding surface of the magnetic head with the medium. Wherein the pair of grooves are deeper toward the outside.