JPH0744820A - Thin film magnetic head element and manufacturing method thereof - Google Patents

Abstract

(57) [Summary] [Objective] To manufacture a thin film magnetic head element having a reproducing head portion and a recording head portion with high dimensional accuracy and a uniform gap width. [Structure] An insulating material 11 is coated on a ceramic substrate 10, and a lower shield layer 12 and a lower read gap layer 1 are further formed.
3 is coated respectively. Next, the MR element 9 is patterned on the upper surface of the lower read gap layer 13. Next, MR element 9
A mask pattern 32 made of copper and having an inverse taper shape is provided in the central portion of, and the lead layer 15 is coated on the entire surface. Then, when the mask pattern 32 is removed, the lead layer 15 having a flat planar shape is connected to the connection portion of the MR element 9. Further, by forming the upper shield layer 19, the lower magnetic layer 22, the gap layer 15, and the upper magnetic layer 22 in this order, a uniform gap layer 21 can be obtained in the recording head portion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film magnetic head, and more particularly to a structure of a thin film MR head element having high resolution and a method for manufacturing the same.

[0002]

2. Description of the Related Art As the performance of magnetic disk devices has increased, so has the performance of thin-film magnetic heads used therein. As a magnetic head using a magnetoresistive effect element for such an application, there is a thin film MR head. Since the output of the thin film MR head does not depend on the peripheral speed, it has a great effect on increasing the capacity of the magnetic disk device. But thin film MR
The head still has many technical problems in practical use.
As one of them, there is a problem of improving the short wavelength reproduction characteristic, and in order to solve this problem, an effective means for narrowing the reproducing head portion gap has not been developed yet.

The structure of a thin film magnetic head for a hard disk produced by the conventional technique will be described below with reference to FIGS. 3 is a perspective view showing the entire structure of the thin film magnetic head, and FIG. 4 is a partially enlarged view of a broken line portion A in FIG. FIG. 5 is a sectional view showing the layer structure of the thin film magnetic head element taken along the broken line B in FIG. As shown in FIG. 3, the thin-film magnetic head has a thin-film magnetic head element 1 integrally formed on the side surface of a slider 2 having a substantially rectangular parallelepiped shape. The thin film magnetic head element 1 is manufactured on the side surface of the ceramic slider 2 by using a thin film molding technique. In the slider 2, three flying rails 3 and a slider groove 4 between each flying rail are integrally formed. When such a thin film magnetic head is mounted on a magnetic disk device, a gimbal is provided on the back surface of the slider 2 so that the recording surface of the hard disk and the slider 2
Are mounted so that they slide or float.

The levitation rail 3 has various forms depending on the application, and is generally made by machining or ion beam etching. In the example shown in FIG. 3, three flying rails 3 and two slider grooves 4 are formed by machining. The thin film magnetic head element 1 is formed in the air outflow direction (front side) of the slider 2 as shown in FIG. FIG. 4 is an enlarged view of the broken line portion A in FIG. 3, in which a coil layer 7 for flowing a recording current is formed between the upper magnetic layer 6a and the lower magnetic layer 6b. As shown in FIG. 4, a substantially triangular upper magnetic layer 6a and a lower magnetic layer 6b are formed on the substantially circular upper insulating layer 5, respectively. And the upper insulating layer 5 to the four terminals 8
Are pulled out, and their terminals are pad portions 8a, respectively. Since the recording head portion and the reproducing head portion are integrally formed in the thin film magnetic head element here, four terminals 8 and four pad portions 8a are provided.

As shown in FIG. 4, a plurality of magnetic layers, shield layers and lead gap layers are formed by a thin film forming technique with a magnetoresistive effect element portion (hereinafter referred to as an MR element) 9 sandwiched therebetween. The opening provided in the central portion of the upper magnetic layer 6 is a back gap portion for joining upper and lower magnetic layers described later.

Next, in the thin film magnetic head element 1 shown by the broken line portion B in FIG. 4, layers provided in the peripheral portion of the MR element 9 will be described with reference to FIG. 5 is a broken line B in FIG.
FIG. 3 is an end view of the portion of FIG. 3 as viewed from the recording surface of the hard disk. First, the ceramic substrate 10 is coated with an insulator 11 such as alumina by a sputtering method. Next, the lower shield layer 12 is formed by coating the upper surface of the insulator 11 with permalloy, sendust, or an iron-based alloy material by electroplating or sputtering. Next, an insulating material such as alumina is applied by sputtering to form the lower lead gap layer 13. Furthermore, MR is formed on a specific surface of the lower read gap layer 13.
The element 9 is formed into a film.

Although the MR element 9 shown in FIG. 5 has a single-layer structure, it may have a 2- to 4-layer structure depending on the bias system for driving the MR element. For example, in a shunt bias, lamination is performed using permalloy (MR layer) and titanium. SA
In L (Soft Adjacent Layer) bias, permalloy,
A spacer such as tantalum and a SAL layer in which a third element such as rhodium is added to iron and nickel are stacked in three layers. With the exchange bias, a ferromagnetic layer, which is an alloy of iron and manganese, is laminated so as to be in direct contact with the MR film.

Now, in order to define the track width of the MR element 9 and to prevent the surface of the MR element 9 from being corroded by the alumina ion etching which is carried out during the formation of a layer above the MR element 9, the upper surface of the MR element 9 is formed. The upper read gap layer 14 of No. 1 is formed. The upper lead gap layer 14 is made of an insulating material such as alumina, and its cross-sectional shape is narrower than the width of the MR element 9, and after formation, the left and right edges are inclined and the tapered portion 14a is inevitably formed. Next, a lead layer 15 is formed to connect the edges of the upper lead gap layer 14. The lead layer 15 is made of a low resistance material such as gold.

Next, the film forming process of the lead layer 15 will be described with reference to FIG.
Will be explained. As shown in FIG. 6A, after the MR element 9 having a constant width is formed on the upper surface of the lower read gap layer 13, the upper read gap layer 14 is formed on the entire surface of the substrate by a sputtering method using a material such as alumina. To film. Then, as shown in FIG. 6B, an etching mask 16 is formed using a photoresist in order to leave a predetermined portion of the upper read gap layer 14. Next, as shown in FIG. 6C, etching is performed with an etchant having selectivity. In this case M
The R element 9 was not etched and the upper read gap layer 14 was not etched.
Only etch. Reactive dry etching may be used instead of the etching solution.

As a result, the upper lead gap layer 14 in the uncoated portion of the etching mask 16 is dissolved. Then, the etching mask 16 remaining on the upper surface of the MR element 9
Are removed using oxygen plasma or a resist stripper. As a result, as shown in FIG. 6C, the upper read gap layer 14 having the track width TW remains, and its edge is partially melted to form an inclined surface.

Next, the lead layer 15 is formed by vapor deposition or sputtering.
To the entire surface of the substrate. Here, gold having low resistance and high thermal stability is usually used for the lead layer 15, but since only gold has a weak adhesion with the upper and lower layers, gold is sandwiched between titanium, chrome, tantalum or the like as an adhesion enhancing layer. Form up and down in shape. Further, in order to apply an exchange bias to the MR layer of the MR element 9, when the MR film is positioned on the uppermost layer of the MR element 9,
An antiferromagnetic film may be provided at the bottom of the lead layer 15.

Next, in order to pattern the lead layer 15 into a certain shape, an etching mask 1 is formed using a photoresist.
Form 7. Then, as shown in FIG. 6D, an opening is provided in a portion of the etching mask 17 facing the flat portion of the upper read gap layer 14. Next, an unnecessary portion of the lead layer 15 is removed by using dry etching such as ion beam etching. Further, the etching mask 17 coated on the upper surface of the lead layer 15 is removed using oxygen plasma or a resist stripping solution. By doing so, the lead layer 15 having a predetermined shape as shown in FIG. 6E or 5 is formed.

Next, referring to FIG. 5, the upper read gap layer 1 is formed.
4 and the upper surface of the lead layer 15 is coated with the second upper lead gap layer 18 over the entire surface. The second lead gap layer 18 is made of an insulating material such as alumina, like the first upper lead gap layer 14. Next, the upper shield layer 19 of permalloy or iron alloy is coated on the entire surface by electroplating or sputtering. The reproducing head unit is manufactured through the above steps.

Next, a method of forming the recording head portion will be described. The lower magnetic layer 20 is formed on the upper surface of the upper shield layer 19 of FIG. 5 by electroplating or the like. The lower magnetic layer 20 is selectively formed with a width slightly narrower than that of the MR element 9. In order to prevent magnetic coupling between the upper shield layer 19 and the lower magnetic layer 20, a separation layer such as alumina may be inserted between the two layers. Next, after the gap layer 21 of the recording head portion is laminated on the entire surface, the upper magnetic layer 22 is partially laminated by electroplating or the like. Although not shown in FIG. 5, the gap layer 21
After laminating, a lower insulating layer made of a novolac-based or polyimide-based resin is formed, a lower coil layer is formed by electroplating, etc., and an upper insulating layer is further laminated in the same manner as the lower insulating layer. To do. Finally, a protective layer 23 of alumina or the like is formed in a thick film state on the upper surfaces of the upper magnetic layer 22 and the gap layer 21 by electroplating or the like, and the fabrication of the thin film magnetic head element is completed.

[0015]

The problems of the conventional thin film magnetic head element thus manufactured are shown in FIGS. 7 and 8.
Will be explained. In the conventional manufacturing method, as shown in FIG. 6C, the taper portion 14a of the upper lead gap layer 14 is formed.
Are inclined with respect to the MR element 9 at an inclination angle of 30 ° or more. Further, since the taper width L1 shown in FIG. 7 is 0.4 μm or less, in the pattern formation of the etching mask 17 as shown in the step of FIG. It is extremely difficult to position the pattern edge of the lead layer 15 on the tapered portion 14a in consideration of the etching accuracy of the lead layer 15 that is used. Therefore, the connecting portion of the lead layer 15 is patterned with a width L2 wider than the taper width L1 of the taper portion 14a. That is, as shown in FIG. 7, the connection portion is formed over the range of the riding width L2 of the tapered portion 14a.

The distance between the upper shield layer 19 and the lower shield layer 12 with respect to the MR element 9 is an important dimension for determining the resolution in head performance. However, according to such a structure, the film thickness g1 of the lower read gap layer 13 can be reduced while ensuring the insulating property with a single layer structure. Further, although the film thickness g2 of the upper read gap layers 14 and 18 can be made uniform in the central portion of the MR element 9, the lead layer 15
The film thickness g3 becomes large in the region where the upper lead gap layer 14 rides on the taper portion 14a. The track width TW of the MR element 9 is defined by the dimension inside the junction between the lead layer 15 and the MR element 9. Upper read gap layer 18
The film thickness g2 as seen from the MR element 9 is the film thickness g4 at the connecting portion.
That is, it has been a major obstacle to improving the recording density.

Further, the protrusion generated in the region where the lead layer 15 rides on the taper portion 14a of the upper lead layer 14 is reflected as it is on the upper lead gap layer 18 and the upper shield layer 19 which are upper layers thereof, and remains as a protrusion. As shown in FIG. 8, when the lower magnetic layer of the recording head portion is formed on the upper shield layer 19 by electroplating, the photoresist 24 is used.
And then exposed to ultraviolet light. Since the track width of the recording head portion is wider than the track width of the MR element 9, the protrusion C formed on the upper shield layer 19 is formed on the photoresist 24.
Will be present in the exposure area. Such a protrusion C
When it is exposed to ultraviolet rays, it causes irregular reflection, resulting in pattern disorder and dimensional variation.

Therefore, as shown in FIG. 5, even after the lower magnetic layer 20 of the recording head portion is formed, the protrusions thereof remain and are reflected in the gap layer 21. When the gap layer 21 is affected by the protrusion, the linearity of the gap line is disturbed, which adversely affects the recording performance. In addition, the protrusions in the gap layer 21 have been a cause of pattern disorder and dimensional variation in the formation of the upper magnetic layer 22.

In the thin film magnetic head element 1 manufactured by the above-described manufacturing method, there is a region where the upper read gap layer is widened, so that it is not possible to obtain a gap of a certain size, and a narrow gap is obtained. It was a big obstacle when it became. Further, the protrusions formed as a result of the lead layer 15 riding on the upper read gap layer 14 have been a cause of fluctuations in the track width of the upper and lower magnetic layers of the recording head portion, disturbance of the pattern, and disturbance of the linearity of the gap.

The present invention has been made in view of such conventional problems, and an object thereof is to provide a thin film magnetic head element having excellent recording / reproducing characteristics and a small dimensional change during manufacturing, and a manufacturing method thereof. And

[0021]

According to a first aspect of the present invention, a slider portion that slides or floats on a recording surface of a magnetic recording medium and an air outflow end of the slider portion are joined to record and reproduce a signal. A thin film magnetic head having a thin film magnetic head element, the thin film magnetic head element comprising a substrate bonded to a side surface of a slider portion, a lower read gap layer formed on the substrate via an insulator and a shield layer, and a lower portion. A magnetoresistive effect element that is patterned on the read gap layer to detect the magnetic flux density of the magnetic recording medium, a lead layer connected to different positions of the magnetoresistive effect element, and a single element that insulates the magnetoresistive effect element and the upper surface of the lead layer. And a reproducing head unit for reproducing a signal by changing the magnetoresistance of the magnetoresistive effect element.

According to a second aspect of the present invention, a step of forming a shield layer on one surface of the substrate, a step of forming a lower read gap layer on the shield layer, and a magnetic flux density detection on a part of the lower read gap layer. For forming a magnetoresistive effect element for a magnetic field, a step of forming a pair of lead layers at different positions of the magnetoresistive effect element, and an upper read gap layer for insulation on the upper surface of the magnetoresistive effect element and the lead layer. A method of manufacturing a thin film magnetic head element, which comprises a step of forming a film, wherein the lead layer is formed by a lift-off method by masking a material that can be removed with an etching solution that does not attack the magnetoresistive effect element. It is a feature.

According to a third aspect of the present invention, a step of forming a shield layer on one surface of the substrate, a step of forming a lower read gap layer on the shield layer, and a magnetic flux density detection on a part of the lower read gap layer. For forming a magnetoresistive effect element for a magnetic field, a step of forming a pair of lead layers at different positions of the magnetoresistive effect element, and an upper read gap layer for insulation on the upper surface of the magnetoresistive effect element and the lead layer. A method of manufacturing a thin-film magnetic head element, which comprises a step of forming a film, wherein the step of forming the lead layer comprises forming a plating pattern using a positive photoresist on the upper surface of the magnetoresistive effect element, A positive taper portion is opened in the plating pattern located in the center of the element, a mask pattern is coated on the positive taper portion, and the plating pattern is removed with an etching solution that does not attack the magnetoresistive effect element. Leaving the path portion, and is characterized in that it has been deposited by coating a conductive lead layer on the upper surface of the magnetoresistive element opposite the tapered portion is formed.

[0024]

According to the invention of claim 1 of the present application having such a feature, the upper read gap layer is formed on the upper surfaces of the magnetoresistive effect element and the lead layer connected thereto without causing large irregularities. . Therefore, on the upper surface of the upper lead gap layer, the lower magnetic layer, the gap layer,
When the upper magnetic layers are respectively formed, the gaps of the gap layer become uniform, and the distribution thereof becomes linear within a certain range of the magnetoresistive effect element.

According to the invention of claim 3 of the present application, when the lead layer is formed on the upper surface of the magnetoresistive effect element, a positive photoresist is used to form a plating pattern, and the central portion of the magnetoresistive effect element is reversed. Apply a tapered mask pattern. Since this mask pattern is a metal such as copper,
The substrate can be heated after coating the lead layer, and the adhesion of the lead layer is improved. Further, a lead layer with high pattern accuracy can be obtained without being greatly affected by the film forming conditions. Further, no protrusion is formed at the connecting portion between the lead layer and the magnetoresistive effect element, and the gap layer of the recording head portion located thereabove is formed uniformly.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of a thin film magnetic head element and a method of manufacturing the same according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a sectional view showing the structure of the thin film magnetic head element of the present embodiment, as seen from the contact surface with the recording medium. Since the completed state of the thin-film magnetic head element is similar to that of the conventional example, the same portions are designated by the same reference numerals and detailed description thereof will be omitted. In FIG. 1, a ceramic substrate 10 is covered with an insulator 11 such as alumina by a sputtering method, and a lower shield layer 12 is formed on the upper surface of the insulator 11, as in the conventional example.

Next, an insulating material such as alumina is coated on the lower shield layer 12 by the sputtering method to form the lower read gap layer 13. Next, the MR element 9 is formed on a specific portion of the lower read gap layer 13. Although the MR element 9 is shown as a single layer in the figure, depending on the driving bias system of the MR element 9, it has a 2-4 layer structure as described above.

FIG. 2 is an explanatory view showing the manufacturing process of this embodiment for forming the lead layer 15 on the MR element 9. After the MR element 9 is formed as shown in step (a) of FIG. 2, the step moves to step (b), and the MR element 9 and the lower read gap layer 1 are formed.
A copper electrode film 30 is formed on the upper surface of 3 by sputtering or vapor deposition. Next, a positive photoresist is used to form a plating pattern 31 of about 2 to 2.5 μm on the upper surface of the electrode film 30. In this case, the opening 31a is provided so that the upper central part of the MR element 9 is opened in a positive taper shape. The taper width of the opening 31a is about 0.5 to 1.0 μm when viewed from the top surface of the plating pattern 31.

Next, copper is attached to the opening 31a by electroplating to form a mask pattern 32. The mask pattern 32 defines the read track width,
Its film thickness is about 1.0 to 1.5 μm. When the image reversal resist is used as a mask material, the pattern accuracy is greatly affected by the exposure amount, the baking temperature of the reversal resist, and the development time, and the stability of the taper size of the opening 31a becomes poor. However, the copper mask pattern 32
If so, since a positive photoresist is used,
The dimensional stability of the reverse taper is improved.

Next, the plating pattern 31 and the mask pattern 32 are entirely exposed to ultraviolet rays, and the plating pattern 31 is removed by using an alkaline developing solution. As a result, the inverse tapered mask pattern 32 is left as shown in step (c) of FIG.

Next, the electrode film 30 is removed by using a chemical etching solution of copper whose main component is ammonium persulfate and whose pH is adjusted to 6 to 7 with sodium hydroxide, as an etching solution for etching only copper. Next, as shown in step (d) of FIG. 2, the lead layer 15 is attached to the upper surface of the MR element 9 on which the lower lead layer 13 and the mask pattern 32 are formed by using vapor deposition or sputtering.

When the image reversal resist is used as a mask material, its heat resistance is so low that the substrate to be the coated surface can hardly be heated. Therefore, in the past, the adhesion of the lead layer 15 was not sufficiently ensured, but since the mask pattern 32 is made of copper in this embodiment, the substrate can be heated and the adhesion of the lead layer 15 can be improved. it can. As the adhesion strengthening layer of the lead layer 15, titanium, chrome, etc. are formed on the top and bottom with gold sandwiched therebetween. As a method of applying an exchange bias to the MR layer of the MR element 9, when an MR film is formed on the uppermost layer of the MR element 9,
An antiferromagnetic film may be formed at the bottom of the lead layer 15.

Next, in order to obtain the desired lead formation, as shown in step (e) of FIG. 2, the central mask pattern 32 of the MR element 9 and the electrode film 30 thereunder are removed by using a chemical etching solution. To do. In this way, the lead layer 15 is formed around the MR element 9 without any protrusion.
In comparison with the lift-off method using an image reversal resist, when copper is used as the mask pattern 32, no resist residue occurs and the MR element 9 is not adversely affected. In the lead layer 15 thus formed, the conventional first
As compared with the case where the upper read gap layer 14 is provided, an abnormal protrusion does not occur, and a pattern joint having a small step is formed.

Next, as shown in FIG. 1, the second upper read gap layer 15, the upper shield layer 19, the lower magnetic layer 20,
The coating of the gap layer 21 and the upper magnetic layer 22 in this order is the same as in the conventional example, and the description of the process is omitted. The gap layer 21 formed by such a process is shown in FIG.
As compared with the one shown in (1), a flat film is formed and its film thickness is uniform within the track width TW range.

[0035]

As described in detail above, according to the present invention, a plating pattern having a positive taper portion is coated on a portion located in the magnetoresistive effect element, and a metal mask pattern is formed on this portion. The coating is applied so that the mask of the reverse taper portion is left. When the lead layer is formed in this state, no protrusion is formed at the connecting portion with the magnetoresistive effect element. Therefore, the gap layer of the reproducing head portion can be narrowed, and at the same time in the reproducing head portion and the recording head portion,
The upper and lower magnetic layers can be formed without disturbing the gap width and the gap pattern.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of a main part of a thin film magnetic head element according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a part of the manufacturing process of the thin film magnetic head element of the present embodiment.

FIG. 3 is an external view showing the structure of a thin film magnetic head of the present example and a conventional example.

FIG. 4 is an explanatory diagram showing a configuration of a magnetic head element in the thin film magnetic heads of the present example and the conventional example.

FIG. 5 is a partial cross-sectional view showing a configuration example of a conventional thin film magnetic head element.

FIG. 6 is an explanatory view showing a part of a manufacturing process of a conventional thin film magnetic head element.

FIG. 7 is a sectional view showing a film thickness distribution of a reproducing head portion in a conventional thin film magnetic head element.

FIG. 8 is an explanatory diagram showing a cross-sectional structure of a photoresist in a manufacturing process of a conventional thin film magnetic head element.

[Explanation of symbols]

 1 Thin Film Magnetic Head Element 2 Slider 3 Flying Rail 4 Slider Groove 6a, 22 Upper Magnetic Layer 6b, 20 Lower Magnetic Layer 7 Coil Layer 9 MR Element 10 Ceramic Substrate 11 Insulator 12 Lower Shield Layer 13 Lower Lead Gap Layer 14, 18 Upper Lead gap layer 14a Tapered portion 15 Lead layer 16 Etching mask 19 Upper shield layer 21 Gap layer 30 Electrode film 31 Plating pattern 31a Opening 32 Mask pattern

Claims (4)

[Claims] 1. A thin-film magnetic head having a slider portion that slides or floats on a recording surface of a magnetic recording medium, and a thin-film magnetic head element that is joined to an air outflow end of the slider portion to record and reproduce signals. The thin-film magnetic head element includes a substrate bonded to a side surface of the slider portion, a lower read gap layer formed on the substrate through an insulator and a shield layer, and a pattern formed on the lower read gap layer. A magnetoresistive effect element for detecting a magnetic flux density of a recording medium, a lead layer connected to different positions of the magnetoresistive effect element, and a single upper read gap layer for insulating the magnetoresistive effect element and an upper surface of the lead layer. Have each,
A thin-film magnetic head element comprising a reproducing head unit for reproducing a signal by changing the magnetic resistance of the magnetoresistive element. 2. A step of forming a shield layer on one surface of a substrate, a step of forming a lower read gap layer on the shield layer, and a magnetoresistive effect for detecting magnetic flux density on a part of the lower read gap layer. Forming a device, forming a pair of lead layers at different positions of the magnetoresistive effect element, and forming an upper read gap layer for insulation on the upper surfaces of the magnetoresistive effect element and the lead layer In the method of manufacturing a thin film magnetic head element, the lead layer is formed by a lift-off method by masking a material that can be removed with an etching solution that does not attack the magnetoresistive effect element. Method for manufacturing thin film magnetic head element. 3. A step of forming a shield layer on one surface of a substrate, a step of forming a lower read gap layer on the shield layer, and a magnetoresistive effect for detecting magnetic flux density on a part of the lower read gap layer. Forming a device, forming a pair of lead layers at different positions of the magnetoresistive effect element, and forming an upper read gap layer for insulation on the upper surfaces of the magnetoresistive effect element and the lead layer In the method for manufacturing a thin film magnetic head element, the step of forming the lead layer comprises forming a plating pattern using a positive photoresist on the upper surface of the magnetoresistive effect element, A positive taper portion is opened in the plating pattern located in the central portion of the mask, a mask pattern is coated on the positive taper portion, and the plating pattern penetrates the magnetoresistive element. It is formed by applying a conductive lead layer on the upper surface of the magnetoresistive effect element in which the reverse taper portion is formed by removing the reverse taper portion by removing with an etching solution that is not present. And a method for manufacturing a thin film magnetic head element. 4. The method of manufacturing a thin film magnetic head element according to claim 2, wherein the mask pattern is made of copper, titanium or aluminum.