JPH08111006A - Magnetic head - Google Patents

Abstract

PURPOSE: To obtain magnetic head which does not affect the writing performance based on waving of a write gap by specifying the angle of the stepped part of the write gap top surface to a specific angle to the horizontal in a magnetic head of a magneto-resistance effect type. CONSTITUTION: A write gap layer 63 is formed by sputtering Al2 O3 on an upper shielding layer 61 of NiFe. The top surface of the layer 61 is nearly completely flattened by electroplating, and/or entire surface etch back by ion milling, etc., or forming of SOG film, etc. The angle of the stepped part at the peak surface of the write gap is made <=5 deg. with respect to the horizontal by this method. An upper magnetic pole 66 is thereafter formed on the layer 63 to complete the MR type magnetic head. As a result, the deterioration in the recording characteristics based on twisting of the write gap according to formation of the finer MR type head is prevented and the recording density is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head and a method of manufacturing the same, and more particularly to a magnetoresistive effect magnetic head (M
R type head) and its manufacturing method.

[0002]

2. Description of the Related Art In contrast to conventional thin film magnetic heads or inductive heads (combined winding type heads), MR type heads utilize the magnetoresistive effect, so that the reproduction output does not depend on the peripheral speed and the output is increased when the sense current is increased. Since it can be made larger, a reproduction output that is 2 to 5 times that of an inductive head can be expected, and since the write head and read head are separate, the number of turns in the write head coil can be reduced. Has been done.

A typical structure of this MR type head is shown in FIG.
Referring to, after forming the lower shield 102 such as sendust on the base material 101, permalloy (soft magnetic film) / Ta (magnetic field separation) / NiFe (magnetoresistive element film)
Laminated structure 103 (permalloy is SAL (soft a
A BCS (bounda) made of CoCrPt or FeMn that extends over both ends of the film is formed with a predetermined width (lead core width).
ry control stabilization)
The lead conductor layer 106 composed of the film 104 and W is formed. Then, the upper shield 108, such as NiCr through the insulating interlayer made of Al ₂ O ₃ on the entire surface, Al ₂ O ₃
A light gap layer 109 made of, for example, is formed, and an upper magnet 110 such as NiFe is formed thereon. With respect to such a magnetic head, the track of the magnetic head moves vertically.

[0004]

In the structure of the MR type head described above, since the step between the magnetoresistive element portion 103 and the extraction electrode 106 extending on both ends thereof is directly reflected on the write gap layer 109, the write gap layer 109 is written. Waviness is generated in the gap layer 109 and the writing phase is deviated to deteriorate the writing characteristics.

Still, the recording density is low and the core width is large.
In this case, the ridge of the write gap layer as shown in FIG.
Ri part (W₂-W₁) Is a small percentage of the core width
However, the recording density improved and
When it becomes necessary to reduce the width, as shown in FIG.
As described above, the waviness of the light gap with respect to the core width (W _Four
-W₃) Becomes larger, and the light gap
The degree to which the swell affects the writing performance also increases.
The swell of Itogap can no longer be ignored. That
Therefore, the waviness of the write gap prevents the writing density from increasing.
ing.

Therefore, an object of the present invention is to provide a magnetic head that does not affect the writing performance based on the waviness of the write gap and a method of manufacturing the same.

[0007]

In order to achieve the above object, the present invention has a magnetoresistive element film having a predetermined width on a lower shield in the vicinity of a sliding surface, and the magnetoresistive element is provided on the lower shield. A pair of extraction electrode layers extending on both ends of the top surface of the film, an upper shield and a write gap layer on the magnetoresistive element film and the extraction electrode, and the magnetic resistance of the upper shield. In a magnetoresistive effect magnetic head having a write upper magnetic pole above the element film, the angle of the step portion of the write gap top surface is 5 ° or less, preferably 2 ° or less with respect to the horizontal. Provide the head.

Similarly, according to the present invention, a magnetoresistive element film having a predetermined width is formed on the lower shield, and a pair of extending from the lower shield to both ends of the top surface of the magnetoresistive element film. A method of manufacturing a magnetoresistive effect magnetic head, comprising forming an extraction electrode, forming an upper shield on the magnetoresistive element film and the extraction electrode, and then forming a write gap layer and a writing upper magnetic pole on the upper shield. Forming the upper shield by electrolytic plating and / or planarizing the top surface of the formed upper shield, for example, overall etch back (ion milling, electrolytic etching, etc.), spin-on-glass (SOG) film formation, flat surface There is also provided a method of manufacturing a magnetoresistive element type magnetic head, which is characterized by performing grinding (lap or the like).

[0009]

According to the present invention, the formation of the waviness of the write gap of the write upper magnetic pole can be suppressed even if there is a step in the magnetoresistive element film portion, and the deterioration of the write characteristics can be prevented. A method of manufacturing such an MR type head is also provided.

[0010]

FIG. 1 is a plan view showing the entire internal structure of a magnetic disk device. When a magnetic disk D is rotating at a high speed, a magnetic head 1 moves in a radial direction of the magnetic disk D to perform a seek operation. Is recorded / reproduced. In the figure, 2 is a spindle, 3 is a suspension, 4 is a drive arm, and 5 is a voice coil motor. When the magnetic disk D is cut at the position of the magnetic head 1 and enlarged, the result is as shown in FIG.

In the thin film type magnetic disk D, 11 is a substrate made of a non-magnetic material such as aluminum or glass, and a NiP plating layer 12 is formed on the surface of the substrate to increase mechanical strength. The Cr underlayer 13 for enhancing the horizontal orientation is formed by sputtering about 1000Å. And CoCrTa or CoNiCr
Sputter magnetic material such as 500 Å for thin magnetic film 1
After forming 4, the protective film 15 is made of carbon 30 or the like.
About 0Å is sputtered, and finally, a fluorine-based lubricating layer 16 such as perfluoropolyether is applied on the order of several tens ofÅ to complete the process.

Information is recorded / reproduced on / from the magnetic disk D by the head element section 18 while the magnetic disk D is rotated at a high speed in the direction of arrow a ₁ and the magnetic head slider 1 is slightly floated by the wind force. The slider 1 of the magnetic head is attached to a suspension (spring arm) 3 via a gimbal 20, and a seek operation is performed by a drive arm 4 of a carriage 22. As described above, due to the simplicity of the mechanism, the CSS (Coat Start) in which the core slider slides without flying when the device is started or stopped.
The Stop method has become popular.

The magnetic head of FIG. 3 is an MR type head,
The head element portion 24 is formed by thin film technology and is made of Al ₂ O.
It is covered with a protective film such as ₃ . The slider 1 has levitation rails 25 and 26 on the left and right of the sliding surface, and on the side opposite to the head element portion 24, the inflow slope 2 for taking in the air flow.
5s and 26s are formed. FIG. 4 shows an explanatory view when a composite thin film magnetic head is used. FIG. 4 (A) is a cutaway oblique view, and FIG. 4 (B) is a sectional view (taken along line XX).

FIGS. 4A and 4B show a composite thin film magnetic head 40 of an electromagnetic conversion head (recording head) and a magnetoresistive (MR) head (reproducing head). Resistance effect head (MR head) 41
Is composed of a rectangular magnetoresistive effect element (MR element) 43 formed on the non-magnetic substrate 42, a lead conductor layer 44 of the MR element 43, and upper and lower magnetic shield layers 45a and 45b.

The lead conductor layer 44 is cut to a predetermined width in the longitudinal direction of the MR element 43 and connected to both ends of an MR layer (described later) of the MR element 43. The MR element 33 and the lead conductor layer 44 are between the magnetic shield element layer 45b and electrically connected by the non-magnetic insulating layer 36.
On the other hand, the electromagnetic conversion type head (inductive head) for recording information on the magnetic disk D is the MR head 4
1 upper magnetic shield element 45a to the lower magnetic pole (first magnetic pole)
And an interlayer insulating layer 49 made of a thermosetting resin, a thin-film coil conductor layer (Cu) 50, and an upper magnetic pole 51 through a recording gap with alumina (Al ₂ O ₃ ) interposed in order on the upper surface thereof.
Are stacked, and information is horizontally recorded by a recording gap 48 formed by an upper magnetic pole (second magnetic pole) 51 and a lower magnetic pole (upper magnetic shield layer) 45a. Further, a protective insulating layer 52 is formed on the upper magnetic pole 51. These are formed by sputtering, vacuum deposition plating, or the like.

In the figure, reference numeral 6 is a protective layer made of a hydrogen-containing carbon (diamond-like carbon) layer, on which a fluoride layer 17 is optionally formed as a lubricating protective layer and applied.
5 and 6 are views for explaining a method for manufacturing a thin film magnetic head, FIG. 5 shows a method for forming a large number of head element portions in a matrix on a substrate, and FIGS. 6 (A) and 6 (B). Is 1
A method for separating and finishing the sliders one by one from the slider blocks in a row is shown.

As shown in FIG. 5, ferrite and Al ₂ O
_A large number of head element portions 24 are formed on the substrate 1w such as _3- TiC.
.. are simultaneously formed in a matrix by a thin film technique, and finally they are separated one by one from the positions indicated by the cutting lines 28 and 29 to complete a thin film magnetic head. However, as the manufacturing order, first, the core slider block 30 in which the head element portions 24 are arranged in one row is formed by cutting and separating at the position of the cutting line 28 in the horizontal direction.

After cutting out the slider block, the surface was washed and a hydrogen-containing carbon layer was formed by the CVD method in the same manner as in the case of the above magnetic disk. A SiC film may be formed as a base adhesion layer of the magnetic head by a CVD method before forming the protective film. Since the CVD apparatus is formed by sintering heat treatment and does not use a sputter target in which impurities are easily mixed, the chemical reaction is performed, so that it is possible to prevent a substance that causes corrosion during film formation from being mixed in.

The core slider blocks 30 thus formed are ground one by one to form the flying rails 25 and 26 as shown in FIG. 6 (A). That is, a groove is formed between the left and right floating rails 25 and 26 and between adjacent sliders. The slider rail is formed by an ion mill. Next, as shown in FIG. 6 (B), the wrapping tape 35 attached to the jig 33 at a constant interval and attached to the rubber surface plate 34 in a state of being cut and separated one by one at the position of the cutting line 29 at the center of the groove. And move it to levitating rail 2
The edges of the edges of Nos. 5 and 26 are ground and chamfered. After the R chamfering, the jigs 33 are peeled off, and each one is adhered and fixed to the gimbal 20 at the tip of the spring arm 3 one by one as in the conventional case, as shown in FIG. Information is recorded / reproduced in a state of floating by the amount G.

FIG. 7 is a sectional view showing a conventional method of manufacturing a thin film magnetic disk in the order of steps, which is also disclosed in Japanese Patent Application No. 3-336495 filed by the applicant of the present invention. In step (1), 11 is a doughnut-shaped substrate made of a non-magnetic material such as aluminum, and is formed in the same size as the magnetic disk to be manufactured. For example, when manufacturing a 2.5-inch small-diameter magnetic disk, the non-magnetic disc 11 is also 2.5-inch.

Then, in step (2), NiP-plated underlayers 12 are formed on both surfaces of the non-magnetic disc 11, and in step (3), the plate surface of the rotating non-magnetic substrate is polished. The tape is pressed to form a fine texture T in the circumferential direction. Next, in the step (4), a Cr underlayer 3 for enhancing the horizontal orientation of the Co alloy is formed on the texture T to a thickness of about 1000Å, and in the step (5), for example, from a Co alloy or the like. Composed magnetic film 1
4 is formed into a film of about 500Å. On this magnetic film 14,
As in step (6), the hydrogen-containing carbon film 15 is used as a protective film.
Is formed to a thickness of about 300Å, and the fluorine-based lubricating layer 16 is finally applied. The Cr layer 13, the thin film type magnetic film 14 and the carbon film 15 are formed by a thin film technique such as sputtering.

The texture T formed in the step (3) is
It is for imparting magnetic anisotropy so that the electromagnetic conversion characteristics at the time of recording / reproducing information are improved. Further, since the carbon film 15 also becomes uneven along the texture T, it is possible to suppress the magnetic head from being attracted to the magnetic disk surface by the lubricant, and to reduce the friction between the magnetic head and the magnetic disk surface. You can

As described above, the conventional magnetic recording medium is
A structure in which an underlayer (Cr) of about several thousand liters, a recording layer of several hundred liters, and a carbon protective layer are sequentially formed on an aluminum substrate or a glass substrate that has been subjected to -P plating treatment. However, in recent years, a diamond-like carbon film (DLC) has been developed as a high hardness protective film.

The magnetic head according to the present invention and the method for manufacturing the same will be described in detail with reference to FIGS. 8 to 12 are cross sections near the air bearing surface of the magnetic head. In step (1), sendust is sputtered to a thickness of 3 μm as a lower shield 52 on a non-magnetic substrate 51 such as an Altic substrate, and patterned by ion milling.

In step (2), a resist 54 is formed on the lower shield 52 on which an insulating layer of Al ₂ O ₃ is formed in a pattern except for the MR element forming portion, and then SAL (NiFeCo) / magnet is formed on the entire surface. The layered structure 55 of the component separation layer (Ta) / MR element layer (NiFe) is 180Å /
A film is formed to a thickness of 100Å / 100Å, and the MR element portion 55 'is formed by a lift-off method of removing the resist 54 together with the laminated structure 55 thereon. The width of the MR element 55 'is about 3μ
m (step (3)).

In the step (4), the MR element part 5 will be used in the future.
5'on the entire surface using the resist 56 having the size of the MR element part 55 'and undercut as a mask.
BCS (Boundary) consisting of 0Å CoCrPt
Control Stabilization) Layer 5
7 and a lead conductor layer 58 made of W having a thickness of 1000 Å is formed by a sputtering method in which the lead conductor layer 58 is formed under the undercut, and the resist 56 is removed by a lift-off method to remove the BCS layer 57 and the lead conductor layer 58 from the MR element part 55. The film is formed so as to extend onto both end portions of the top surface of ′.

A step (A portion) is produced by the lead conductor layer 58 on the MR element portion 55 'thus obtained (step (5)). In step (6), the entire surface is sputtered by A
2000 Å of l ₂ O ₃ is formed into a nonmagnetic insulating layer 59. On the top surface of this Al ₂ O ₃ layer, the step of the A portion continues. Therefore, according to the present invention, in the step (7), Ti (500Å) / NiFe (1000Å) is vapor-deposited first, and then NiFe is electrolytically plated to a thickness of about 3 μm. The Ti layer 60 is an underlayer that promotes the adhesion growth of NiFe on Al ₂ O ₃ , and also the vapor-deposited NiFe layer 6
1-1 is a base layer for the electroplated NiFe layer 61-2. The feature of the method of the present invention is that the top surface of the upper shield 61 is flattened by forming the upper shield 61 made of NiFe by electrolytic plating.
That is, according to the electroplating method, despite the step on the MR element portion 55 ', the plating is deposited on the surface of the electroplated layer so that the step is eliminated. Therefore, electrolytic plating N
The step on the surface of the iFe layer 61 does not eliminate the step on the MR element part 55 ', but it is significantly reduced (part B).

Then, in step (8), the entire surface is subjected to ion milling to etch back a thickness of about 1 μm, whereby the level difference is further reduced (C portion). Further, in step (9), a silicone resin or other silicon compound is applied on the NiFe layer 61 by spin coating to a volume of about 1000 Å and baked to convert it to silica. Since the SOG layer 63 is formed by the spin coating method, the top surface is completely flat. The SOG layer 62 may be spread over the entire surface, but it is desirable that the SOG layer 62 fills only the steps.

Therefore, in the step (10), Al ₂ O is formed on the NiFe upper shield 61 having the SOG layer 63.
_The light gap layer 63 is formed by sputtering ₃ to a thickness of about 1000Å. The top surface of the write gap layer 63 is almost completely flat. In the above, as the method for flattening the upper shield, electrolytic plating of the upper shield, overall etch back by ion milling, and SOG formation were performed.
Alternatively, it is clear that even if only a specific process among these is performed, a corresponding effect can be obtained.

Referring to step (11), Ti (100
Å) / NiFe (1000Å) 64 is vapor-deposited, and then a resist 65 having a pattern excluding the upper magnetic pole formation region is formed, and then NiFe plating is performed on the entire surface to obtain a NiF of about 3.5 μm.
The e layer is formed, and the resist 65 is removed to form the pattern (core) of the top pole 66. Thus, FIG.
The MR type magnetic head shown in FIG. In this MR type magnetic head, the write gap layer 63 is completely flat and has no step.

Here, referring to FIG. 13, when the upper magnetic pole 63 is formed on the write gap layer 63, the step of the write gap layer 61 can be expressed by an angle θ formed by the step with the horizontal plane. This angle θ will be referred to as a write gap angle here. When an MR type magnetic head having the same structure as described above is manufactured without performing the flattening process (including electrolytic plating) of the upper shield which is conventionally performed. Moreover, when only the electrolytic plating method is adopted as the flattening treatment, when the upper shield is only etched back by ion milling, when only the SOG layer is formed,
FIG. 14 shows the result of measuring the write gap angle θ in the case where these three flattening treatments are combined and carried out as in the above embodiment. The effect of flattening is clear.

Further, the MR reproduction characteristics (D50) of the above MR type head were evaluated. D50 is a frequency at which the recording density is increased from a low frequency to a high frequency and the reproduction output becomes 50% of the output at the low frequency (recording density-here, flux changer inch (fc
i)). This result is also shown in FIG. FIG. 14 clearly shows the relationship between the write gap angle θ and the improvement of the reproduction output.

[0033]

The deterioration of the recording characteristics due to the twisting of the write gap due to the miniaturization of the MR type head is prevented, which contributes to the improvement of the recording density.

[Brief description of drawings]

FIG. 1 shows an overall view of a magnetic disk device.

FIG. 2 shows a magnetic head on a magnetic disk.

FIG. 3 shows an overview of a magnetic head.

4A and 4B show the content structure of a composite magnetic head.

FIG. 5 shows a mass production method of a thin film magnetic head.

6 (A) and (B) show the manufacture of a slider block.

7 (1) to (6) show manufacturing steps of a magnetic disk.

FIG. 8 is a manufacturing process (1) to MR type head of the embodiment;
(3) is shown.

FIG. 9 is a manufacturing process (4) of the MR type head of the embodiment;
(6) is shown.

FIG. 10 is a manufacturing process (7) of the MR type head of the embodiment;
(9) is shown.

FIG. 11 is a manufacturing process (10) of the MR type head of the embodiment;
(11) is shown.

FIG. 12 shows a finished product of the MR type head of the embodiment.

FIG. 13 illustrates a write gap angle θ.

FIG. 14 shows the relationship between the write gap angle θ and the reproduction output.

FIG. 15 shows a conventional MR type head.

16A and 16B show twist of the write gap layer of the conventional MR type head.

[Explanation of symbols]

51 ... substrate 52 ... lower shield 54,56,65 ... resist 55 '... MR element portion 58 ... lead conductor layer 59 ... Al ₂ O ₃ 61 ... upper shield 62 ... SOG 63 ... write gap layer 66 ... upper pole

Claims (4)

[Claims] 1. A magnetoresistive element film having a predetermined width is provided on a lower shield, and a pair of lead conductor layers extending from above the lower shield on both ends of a top surface of the magnetoresistive element film are provided. In the magnetoresistive effect magnetic head, which has an upper shield and a write gap layer on the magnetoresistive element film and the extraction conductor layer, and has an upper magnetic pole for writing above the magnetoresistive element film of the upper shield. A magnetic head characterized in that the angle of the stepped portion on the top surface of the gap is 5 ° or less with respect to the horizontal. 2. The magnetic head according to claim 1, wherein the angle is 2 ° or less. 3. A magnetoresistive element film having a predetermined width is formed on the lower shield, and a pair of lead conductor layers extending from the lower shield to both ends of the top surface of the magnetoresistive element film are formed. ,
In the method of manufacturing a magnetoresistive effect magnetic head, wherein an upper shield is formed on the magnetoresistive element film and the lead conductor layer, and then a write gap layer and an upper magnetic pole for writing are formed on the upper shield. A method of manufacturing a magnetoresistive element type magnetic head, characterized in that a top surface of an upper shield formed and / or formed by electrolytic plating is subjected to a planarization treatment. 4. The flattening process is performed by at least one of full etching back of the top surface of the upper shield, formation of a spin-on-glass (SOG) film on the upper shield, and surface grinding of the top surface of the upper shield. Item 3
The described method.