JPH08279108A - Thin-film magnetic head and its production - Google Patents

Abstract

PURPOSE: To obtain a thin-film magnetic head having the excellent reliability of conductor coils by improving coil pattern defects and a process for production of the head. CONSTITUTION: This thin-film magnetic head has an upper layer magnetic core 2 and a lower layer magnetic core 1 and is formed with the conductor coils 3 via a coil flattening layer 7 in the upper part of the lower layer magnetic core 1. The lower layer magnetic core 1 is embedded into a nonmagnetic inorg. insulating material layer 13 and is flattened. The insulating material layer 13 consists preferably of Al2 O3 or SiO2 . On the other hand, the process for production has a stage for forming the lower layer magnetic core 1 of a prescribed shape on a substrate 4, then forming the film of the upper insulating material 13 covering the lower layer magnetic core 1 and flattening the insulating material film 13 until the lower layer magnetic core 1 is approximately exposed, a stage for forming the conductor coil 3 via the coil flattening layer 7 thereon and a stage for forming the upper layer magnetic core 2 to a prescribed shape.

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 having an upper magnetic core and a lower magnetic core, and a conductor coil formed on the lower magnetic core via a coil flattening layer, and a method of manufacturing the same. Regarding

[0002]

2. Description of the Related Art Conventionally, a thin film magnetic head has been known as a magnetic head mounted in, for example, a data recorder of a computer.

This thin film magnetic head is a magnetic head in which thin film layers such as a magnetic film and an insulating film are laminated in multiple layers and a conductor coil is further formed. This thin-film magnetic head has a unique thin-film pattern formation method such as film formation, photolithography, etching, plating, lift-off, etc., and is capable of mass-producing wafers with uniform quality. The fact that the upper short magnetic path has a low inductance and the like can be mentioned, and further high performance including materials is being attempted in response to the recent high density.

In such a thin film magnetic head, for example, as shown in FIG. 28, a lower magnetic core 101, an upper magnetic core 102 and Cu made of permalloy (Ni--Fe) or the like are used.
A magnetic circuit portion formed of a conductive coil 103 and the magnetic gap 106 formed of SiO ₂ or the like made of equal Al ₂ O ₃ -
It is configured by being sandwiched between a base substrate 104 made of TiC, ferrite, etc. and a ceramic-based protective substrate 105.

An outline of the method of manufacturing the thin film magnetic head is as follows. A lower magnetic core 101 made of a soft magnetic material layer is formed on the base substrate 104, and the lower magnetic core 101 and the conductor coil 103 are insulated from each other. A coil flattening layer 114 for achieving the above is formed, and the conductor coil 103 is spirally formed on the surface thereof.

By the way, among such conventional thin-film magnetic heads, particularly in a multi-channel thin-film magnetic head having a lower-layer magnetic core 101 made of a ferromagnetic metal thin film, the lower-layer magnetic core 1 may be used depending on its application.
There are a type in which 01 is divided for each channel and a case in which each channel is common. In general, when the magnetic recording medium (not shown) slides in only one direction with respect to the magnetic head, the latter lower magnetic core 101 is of a type common to all channels, while on the other hand, with respect to the magnetic head, For the purpose of a data recorder (so-called data storage) in which a recording medium slides from both sides, the former type that is divided into channels is used.

[0007]

However, in the thin-film magnetic head of the type in which the lower magnetic core 101 is divided for each channel, as shown in FIG.
03 will cross the end of the lower magnetic core 101,
The shape of this lower layer end portion greatly affects the shape of the conductor coil 103.

For example, as a method of forming the conductor coil 103, there are generally two methods of film formation-photolithography-etching and photolithography-plating.

However, by any of these methods, the above-mentioned conventional thin film magnetic head is used in the lower magnetic core 10.
In the photolithography process of the portion that crosses the end portion of 1, the step is generated in the lower magnetic core 101, and the conductor coil 1
03 pattern defect (short circuit defect) occurs.

Therefore, in order to prevent this, as shown in FIG. 30, the lower magnetic core 1 is provided under the conductor coil 103.
There has also been proposed a technique for forming a leveling resist pattern 114p having the same height as 01 and a leveling resist pattern 114p for the purpose of insulating and leveling the conductor coil 103.

However, as shown in FIG. 31, the shape of the taper portion of the lower magnetic core 101 differs depending on the patterning deviation, whether the lower magnetic core 101 is formed by, for example, ion milling or pattern plating. A V-shaped groove 110 is generated at the boundary with the magnetic core 101, which has a problem of inducing a defective coil pattern of the V-shaped groove 110 (in FIG. 31, the symbol H indicates the shoulder width. Show.).

The step eliminating resist pattern 11 is also provided.
3 and the flattening resist pattern 114p have undergone a heat treatment process at about 300 ° C. in order to have heat resistance and solvent resistance, which causes a change in the shape of the shoulder-shaped resist as shown in FIG. Had the problem of causing.

This adversely affects the use of the mask contact method in the coil patterning device.
In particular, it causes a coil pattern defect on the outer circumference of the coil where the distance between the photomask and the resist surface is large, and the conductor coil 103 has a large aspect ratio.
When the interval of 03 is narrow, or when the conductor coil 103 is wound in two or more layers, and the flattening resist pattern 114 is formed on the conductor coil 103 and overlapped, the conductor coil on the upper layer side As the number becomes 103, the occurrence of the shape change of the above-mentioned shoulder-dip type resist became remarkable.

Further, the flattening resist pattern 114p
When using as a constituent material of a thin film magnetic head, the use of the magnetic cores 101 and 102 is limited due to its heat resistance. Specifically, in the magnetic cores 101 and 102,
There has been a problem that sendust and the like, which can obtain soft magnetism, cannot be used by performing heat treatment at about 500 ° C.

Therefore, the present invention aims to improve the coil pattern defect, which has been a problem in the past, and to obtain a thin-film magnetic head in which the reliability of the conductor coil is excellent, and a manufacturing method thereof. The purpose is to provide.

Further, the present invention is a thin film magnetic head and a thin film magnetic head capable of expanding the design flexibility by expanding the usable range of the magnetic core, which has been restricted in use from the viewpoint of heat resistance in the conventional thin film magnetic head. It is intended to provide a manufacturing method.

[0017]

In order to achieve the above object, the present inventor has a conductor coil having an upper magnetic core and a lower magnetic core, and a coil flattening layer above the lower magnetic core. In the thin-film magnetic head in which the lower magnetic core is embedded in the non-magnetic inorganic insulating material layer,
It is characterized by being flattened.

Further, it is characterized in that it has a plurality of layers of conductor coils, and each conductor coil is flattened by a coil flattening layer.

Further, the non-magnetic inorganic insulating material layer is made of Al.
It is characterized by being made of ₂ O ₃ or SiO ₂ .

On the other hand, in the method of manufacturing the thin film magnetic head of the present invention, after the lower magnetic core having a predetermined shape is formed on the substrate,
A step of forming a non-magnetic inorganic insulating material film covering the lower magnetic core, and flattening the non-magnetic inorganic insulating material film until the lower magnetic core is substantially exposed; The method is characterized by including a step of forming a conductor coil and a step of forming the upper magnetic core into a predetermined shape.

Further, in the step of forming the coil conductor, the plurality of layers of conductor coils are each flattened by the coil flattening layer.

Furthermore, the coil flattening layer is a film of Al ₂ O ₃ or SiO ₂ .

[0023]

According to the thin film magnetic head of the present invention, since the lower magnetic core has a structure in which it is embedded in a nonmagnetic inorganic insulating material layer and is flattened, a conventional thin film magnetic head having a resist pattern having poor heat resistance is arranged. Unlike the above, the lower magnetic core can effectively suppress the occurrence of a step on the surface on which the conductor coil is formed due to the shoulder sag phenomenon. As a result, in the photolithography process, the entire surface on which the conductor coil is formed can be brought into close contact with the photomask for exposure.

Further, the structure in which the lower magnetic core is embedded in the non-magnetic inorganic insulating material layer to be flattened can suppress the occurrence of a step on the surface on which the conductor coil is formed, so that a plurality of layers of conductor coil are formed. Will also be excellent.

Further, if each coil conductor in a plurality of layers is flattened by the coil flattening layer, an excellent effect is obtained in forming each conductor coil.

When a resist having poor heat resistance is removed from the structure of the thin film magnetic head to form a coil flattening layer of an Al ₂ O ₃ or SiO ₂ film, the soft magnetic properties of the lower magnetic core and the upper magnetic core are reduced. Even if the heat treatment temperature for obtaining is high, it can be used.

Specifically, the magnetic core is conventionally about 350.degree.
Although it is not limited to the above, it is possible to use sendust or the like that can obtain soft magnetism by performing a heat treatment at about 500 ° C.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a thin film magnetic head to which the present invention is applied will be described below with reference to the drawings.

First Embodiment As shown in FIG. 1, the thin-film magnetic head of the present embodiment uses a lower magnetic core 1, an upper magnetic core 2, a conductor coil 3, a magnetic gap G, and a coil flattening layer 7 to form a magnetic field. A circuit section is configured. The thin film magnetic head is constructed by sandwiching the magnetic circuit portion between the base substrate 4 made of Al ₂ O ₃ —TiC and the protective substrate 5.

In this embodiment, the base substrate 4 is made of Al ₂ O ₃ --TiC as a material from the viewpoint of high thermal conductivity and strength. The base substrate 4 serves as a base for forming individual patterns of the magnetic circuit, such as film formation, photolithography, etching, plating, lift-off, and other patterns unique to the thin film.
Actually, four magnetic circuit units are formed on the upper side at a predetermined interval. That is, this embodiment is a multi-channel thin film magnetic head.

The protective substrate 5 is provided to protect the magnetic circuit portion from external force or the like, or to make a contact surface during sliding contact with the magnetic recording medium, and Al ₂ O _{3 is formed} on the upper magnetic core 2.
The protective film 8 made of is flattened by a flow from film formation to lapping, and is integrated through a bonding layer made of epoxy resin. The protective substrate 5 is the base substrate 4
Al ₂ O ₃ —TiC is used for the same reason.

The lower magnetic core 1 and the upper magnetic core 2 are made of an iron-based microcrystalline material such as Fe-Al alloy or Fe-Ga-Si-Ru alloy, and are magnetic recording medium slides that are in sliding contact with the magnetic recording medium. On the moving surface side, a magnetic gap G is sandwiched via a magnetic gap spacer made of SiO ₂ , and at the center thereof, the conductor coil 3 embedded by a coil flattening layer 7 made of resist is sandwiched and The sides directly contact each other without the magnetic gap G, and form a closed magnetic circuit.

In particular, in the thin film magnetic head of this embodiment, the lower magnetic core 1 of the magnetic cores 1 and 2 is used.
In addition, the Al ₂ O ₃ film is entirely embedded and planarized by the method described later. In the present embodiment, the lower magnetic core 1 is made of Al as a planarizing material.
The film 13 of ₂ O ₃ is formed by the bias sputtering method, but the present invention is not limited to this, and a SiO ₂ film, a Si ₃ N ₄ film, etc.
A known inorganic insulating film can be used. However, from the viewpoint of film stress, the Al ₂ O ₃ film 13 is small and easy to use.

With such a flattened structure, it is possible to obtain a thin film magnetic head in which the defect of the coil pattern is improved and the reliability of the conductor coil is excellent.

By the way, the lower magnetic core 1 is insulated from the conductor coil 3 on the lower magnetic core 1 through the magnetic gap G, and the surface of the lower magnetic core 1 is flattened so that the conductor coil 3 is accurately formed. It is for forming.

As shown in FIGS. 2 to 5, the lower magnetic core 1 is manufactured by filling the entire surface with an Al ₂ O ₃ film and flattening it. That is, FIG.
As shown in FIG. 3, an iron microcrystalline material is formed into a film, the lower magnetic core 1 is processed by ion milling or the like, and an Al ₂ O ₃ film 13 is formed on the entire surface by bias sputtering. To be done.

In this case, the Al ₂ O ₃ film 1 to be formed first
The thickness of 3 needs to be equal to or larger than the thickness of the lower magnetic core 1.
In the case of this embodiment, the thickness is twice the thickness of the lower magnetic core 1.

Next, as shown in FIG. 4 and FIG.
The film 13 of l ₂ O ₃ is flattened by the flattening process until the lower magnetic core 1 is almost exposed. As a result, the surface of the Al ₂ O ₃ film 13 and the surface of the lower magnetic core 1 are flush with each other, and a flat surface without V-shaped grooves or steps is obtained.

Further, the conductor coil 3 serves to supply the recording signal from the recording / reproducing apparatus to the medium and to transmit the reproducing signal from the medium to the recording / reproducing apparatus side. In this embodiment, the sulfuric acid is used. It is formed by copper pattern plating.

In this embodiment, the conductor coil 3 is embedded with the coil flattening layer 7 made of resist.
In order to use the resist as the coil flattening layer 7, the upper magnetic core 2 and the lower magnetic core 1 are made of the iron-based microcrystalline material, but the magnetic material is limited to those having a relatively low heat treatment temperature. Has been done. Specifically, it is below the effective temperature of the resist, and in this case is below 300 ° C. Further, since the surface of the magnetic film is flattened, a material having a small magnetostriction is preferable.

However, the advantage of using the resist as the coil flattening layer 7 is that a gentle magnetic path shape can be obtained and an etching step is not required for forming the magnetic path in the manufacturing method described later.

The conductor coil 3 may be formed as a plurality of layers including a coil lower layer, an inter-coil layer, and a coil upper layer. Even if the lower magnetic core 1 is formed as a plurality of layers in this way, if the lower magnetic core 1 is flattened with Al ₂ O ₃ , the shoulder of one layer of the coil flattening layer 7 due to the resist can be ignored and a coil short circuit occurs. It is possible to form the conductor coil 3 without doing so. When formed as a plurality of layers, each layer may be flattened by the coil flattening layer 7.

In this case, the coil flattening layer 7 may be formed of a film of Al ₂ O ₃ or SiO ₂ instead of the resist. In this way, by removing the resist having poor heat resistance from the structure of the thin film magnetic head, it is possible to use one having a high heat treatment temperature for obtaining the soft magnetism of the lower magnetic core 1 and the upper magnetic core 2 as described later. is there. FIG.
In the figure, reference numeral 10 is an insulating film 10 of Al ₂ O _{3 which} plays a role of insulating and flattening the lower magnetic core 1 and the base substrate 4.

As the film forming method, a bias sputtering method, a CVD (chemical paper deposition) method, or the like is suitable in view of the step coverage of the film.

The thin-film magnetic head configured as described above is excellent in forming the conductor coil 3 that does not cause a step by flattening the surface on which the conductor coil 13 is formed via the magnetic gap G. This is the structure of a thin film magnetic head. Therefore, in the photolithography process, the entire surface on which the conductor coil 13 is formed can be brought into close contact with the photomask for exposure.

Method of Manufacturing Thin-Film Magnetic Head Next, a method of manufacturing the thin-film magnetic head having the above structure will be described.

First, as shown in FIG. 6, Al ₂ O ₃ --Ti
An insulating film 10 of Al ₂ O ₃ is formed on the base substrate 4 made of C, for example, to have a thickness of 2 μm. Insulating film 10 of Al ₂ O ₃ here
Is the lower magnetic core 1 to be formed next and the base substrate 4 described above.
RF sputtering system, which plays the role of both insulation and planarization.
It is formed by the method of.

Next, as shown in FIGS. 7 and 8, a lower magnetic film made of an iron-based microcrystalline material is formed to a thickness of, for example, 4 μm by a method of RF sputtering, and a predetermined resist pattern is formed in a photolithography process. Then, etching is performed by an ion milling method and the resist is peeled off, whereby the lower magnetic core pattern 11 is formed.

Next, as shown in FIG. 9, an Al ₂ O ₃ film 8 nonmagnetic inorganic insulating material layer) 13 is formed on the entire surface of the substrate so as to cover the lower magnetic core pattern 11 by bias sputtering, for example, to a thickness of 8 μm. , The planarization processing step shown in FIG. The thickness of the Al ₂ O ₃ film 13 needs to be equal to or greater than the thickness of the lower magnetic core 1. In the case of this embodiment, the thickness is twice the thickness of the lower magnetic core 1.

Next, as shown in FIG. 10, the process proceeds to a flattening process, where the flattening process consists of two types of surface processing methods.

One is called the above-mentioned diamond polish (hereinafter referred to as "DP processing"), and the other is the chemical mechanical polish method (hereinafter referred to as "C").
"MP processing". ) Is called. In both cases, the surface is processed in a wafer state.

First, in the DP processing, for example, a platen of copper, tin or the like is used, and a diamond slurry having a particle size of 1 μm is used as an abrasive material. The surface of the Al ₂ O ₃ film 13 is processed by the DP processing until the lower magnetic core pattern 11 is exposed.

In this case, strictly speaking, the lower magnetic core pattern 11 is more than the lower magnetic core pattern 11 is exposed.
It is preferable to perform surface processing so that the upper Al ₂ O ₃ film 13 is left to have a thickness of about 100 nm. The polishing amount in this case is in the vicinity where the lower magnetic core pattern 11 is exposed, that is, about 4 μm.

Next, in the CMP processing, for example, a surface plate to which a buff cloth is attached is used, and alkaline Si coated particles are used as the abrasive. CMP processing is
Unlike the physical polishing of DP processing, it has the property of chemical polishing with alkali. Further, in the DP processing, the object of polishing is not relatively selected, whereas in the CMP processing, it is possible to impart selectivity to the polishing object by selecting an abrasive. As for the property of polishing, in this case, DP processing is rough cutting, while CMP processing has a strong finishing meaning.

By such CMP processing, processing is performed so as to remove scratches generated by DP processing, the lower magnetic core pattern 11 is exposed, and a flat wafer surface is obtained. However, the polishing amount for CMP processing is A
The thickness of the film 13 of l ₂ O ₃ is about 200 nm. This is because excessive CMP processing is not preferable because it causes protrusion of the lower magnetic core pattern 11 because of the selectivity described above.

In this way, the lower magnetic core pattern 11 is formed.
After the Al ₂ O ₃ is flattened, as shown in FIG.
A magnetic gap film 16 made of iO _{2 is formed} to a thickness of 2 μm. As the material of the magnetic gap film 16, Al ₂ O ₃ or the like can be used in addition to SiO ₂ of this embodiment, but SiO _{2 of} this embodiment is preferable from the viewpoint of its etching property.

Next, as shown in FIG. 12, a predetermined resist pattern is formed by a photolithography process, and the back gap BG is etched by a method such as ion milling or reactive ion etching. In this case, the gap film 16 is formed, that is, Si
The lower magnetic core pattern 11 on the back side is exposed by etching O ₂ or Al ₂ O ₃ by 2 μm.

Next, as shown in FIG. 13, as a base of the conductor coil 3 made of copper plating, for example, Ti 50 nm is used.
/ Cu 200 nm is formed into a film by the RF sputtering method or the like.

Next, a predetermined resist pattern is formed by a photolithography process, and copper sulfate plating, for example, of 4 μm is performed. After that, the resist pattern is peeled off and the underlying Ti / C is formed by ion milling or the like.
When u is etched, the first conductor coil 3a is formed.

In this embodiment, the L / S (line / space) of the first conductor coil 3a is 11 μm.
m / 4 μm, and the coil aspect ratio, that is, the ratio of height to width in the coil cross section is 1.

Next, as shown in FIG. 14, a predetermined resist pattern is formed by a photolithography process,
The first flattening layer 17 made of an insulating material is formed by performing heat treatment at about 0 ° C.

Here, when the conductor coil 3 has a two-layer structure, as shown in FIG. 15, the second conductor coil 3b of the second layer is formed in the same manner as the first conductor coil 3a of the first layer. Will be formed. At this time, the formation of the second conductor coil 3b of the second layer is different from the formation of the first conductor coil 3a of the first layer, whereas the lower part of the conductor coil 3 is flat in the first layer. The second layer is formed by applying a second coil flattening layer 27 made of a heat-treated insulating material to the second conductor coil 3b.
This is because the resist has shoulder sagging because it has a lower part.

In this regard, in the conductor coil 3, when the space aspect ratio is 1, the lower layer magnetic core 1 is
With the structure of being embedded in l ₂ O ₃ and flattened, the shoulder sag of one layer of the coil flattening layers 17 and 27 by the resist can be ignored, and the conductor coil 3 can be formed without causing a coil short. .

Coil flattening layer 1 made of resist
When two or more layers of 7 are overlapped and an attempt is made to further form the conductor coil 3 thereon, it is known as a result of an experiment that about 90% of the conductor coils 3 are short-circuited on the outer periphery of the conductor coil 3. As described above, the width varies depending on the coil forming width, the coil space aspect ratio, and the size of the shoulder of the first coil flattening layer 17 made of resist.

In this way, the second-layer conductor coil 3b is formed.
16 is formed, a predetermined resist pattern is formed by a photolithography process as shown in FIG.
The second coil flattening layer 27 made of an insulating material is formed by performing a heat treatment at about ° C.

Here, the conductor coil 3 and the coil flattening layers 17 and 27 can be formed without any problem by the above-mentioned method. In this embodiment, a resist is used as the coil flattening layers 17 and 27. The reason is that, by forming the magnetic path with a heat-cured resist, a gentle magnetic path shape may be obtained, and an etching step may not be required to form the magnetic path. In this regard, the second described later
Is different from the embodiment described above.

Next, as shown in FIG. 17, a film of the upper magnetic core 2 made of an iron microcrystalline material is formed to a thickness of, for example, 4 μm by a method such as the RF sputtering method, and a predetermined resist pattern is formed in the photolithography process. Is formed, etching is performed by a method such as ion milling, and the resist is peeled off to form the upper magnetic core pattern 12. Above,
The formation of elements that are the elements of the head is almost completed.

Next, in order to form the lead-out portion of the element, pattern plating with copper sulfate is performed.

First, on the wafer on which the upper magnetic core pattern 12 is formed, for example, Ti is used as a base for terminal plating.
A film of 50 nm / Cu 200 nm is formed by RF sputtering or the like. Then, as shown in FIG. 18, a predetermined resist pattern is formed by a photolithography process, and, for example, 30
Apply μm copper plating. After that, the resist pattern is peeled off and the underlying Ti / Cu is etched by ion milling or the like to form the copper terminal 31.

Next, as shown in FIG. 19, a film 32 of Al ₂ O ₃ is deposited by bias sputtering to a thickness of 35 μm, and DP, C
The wafer surface is flattened through MP processing. Naturally, the copper terminal 31 is exposed at this point. Through these steps, the wafer 33 of this embodiment is completed.

The completed wafer 33 is cut into a chip size by a cutting machine or the like, and Al ₂ O ₃
-The protective substrate 5 made of TiC or the like is joined by resin, and thereafter, the portion serving as the medium sliding contact surface is cylindrically ground, or
It is processed into an arc shape by profile grinding, and then tape wrapping, etc. is applied to complete a head chip. That is, the thin film magnetic head as shown in FIG. 1 is completed.

Although the embodiments of the thin film magnetic head to which the present invention is applied have been described above, the present invention is not limited to the above-described embodiments, and is applicable to all thin film magnetic heads having the divided lower magnetic core 1. It can be applied to.

In the present embodiment, the coil flattening layers 17 and 27 made of resist are used from the viewpoint of no problem in forming the conductor coil 3 and cost. However, if there are restrictions on the heat treatment of the magnetic core, or in the case of a thin film magnetic head structure that requires three or more coil layers,
It is also possible to form all the coil flattening layers with a film of Al ₂ O ₃ or SiO ₂ .

[0074] The second embodiment configuration of the second embodiment, a coil planarization layer 17, 27 by resist formed in the first embodiment, SiO ₂
The bias sputtered film is flattened, and other structures are the same as those in the first embodiment.

The manufacturing method of the second embodiment will be described with reference to FIGS. 20 to 27. First, as shown in FIG. 20, the first conductor coil 53a is formed until the first conductor coil 53a is formed. It is created in the same manner as in the embodiment of FIG. That is, the second
This example is prepared in the same manner as in the first example, including forming an Al ₂ O ₃ film on the lower magnetic core 51, which is a feature of the present invention, and performing a flattening process. Therefore, in FIGS. 20 to 27 described below, the same components as those in the first embodiment are designated by the same reference numerals.

In the second embodiment, after forming the first conductor coil 53a of the first layer, a columnar portion 53c for coil contact is formed by copper pattern plating as shown in FIG. _{It is} applied by the bias sputtering method of ₂ O ₃ or SiO ₂ . After that, as shown in FIG. 22, the wafer surface is flattened through DP processing and CMP processing to expose the contact ends of the columnar portions 53c of the contacts.

Next, as shown in FIG. 23, the second layer of the second
As a base of the conductor coil 53b of
A film of m / Cu 200 nm is formed by an RF sputtering method or the like, copper pattern plating is performed with copper sulfate, resist stripping and underlying Ti / Cu etching are performed, and a second conductor coil 53b of the second layer is formed.

Here, when the third conductor coil or more is required, as described above, the formation of the coil contact pillar-the bias sputtering method of Al ₂ O ₃ or SiO _2- DP processing (or CMP processing). The coil flattening layer 17 is formed by the above flow, and the formation of the conductor coil 53 thereon may be repeated.

Subsequently, as shown in FIG. 24, a predetermined resist pattern is formed by a photolithography process and copper plating is performed. After that, the resist pattern is peeled off and the underlying Ti / Cu is etched by ion milling or the like to form the copper terminal 54.

Then, as shown in FIG. 25, a SiO ₂ film 55 is formed by bias sputtering, and the wafer surface is flattened through DP and CMP processes.

Subsequently, as shown in FIGS. 26 and 27,
A predetermined resist pattern is formed in the photolithography process, and the flattening layer of the back gap BG is etched by a method such as reactive ion etching or ion milling to expose the lower magnetic core 51 of this portion, and the resist is removed. When peeled off, a predetermined magnetic path shape is obtained. Through these steps, the wafer 56 of the second embodiment is completed.

Incidentally, in the second embodiment, unlike the first embodiment, the magnetic path must be newly formed by the etching process. From this, as the material of the coil flattening layer, the upper layer of the coil or the inter-coil layer is made of Si rather than Al ₂ O _{3 in} terms of etching property.
O ₂ is preferred. Regarding the magnetic path formation method, after forming the coil of the final layer, bias sputtering of SiO ₂ or Al ₂ O ₃ is performed, and the wafer surface is flattened through DP and CMP processing.

In Example 1, the lower magnetic core of Al ₂ O _{3 was used.}
The magnetic gap G formed immediately after planarization by
In the case of the above embodiment, the magnetic gap G must be newly formed because it is lost in the above magnetic path forming step. This is a magnetic gap film 16 made of SiO ₂ or the like.
Is formed by a method such as an RF sputtering method, a predetermined resist pattern is formed in a photolithography process, and the back gap BG is etched by a method such as reactive ion etching or ion milling.
After that, from the formation of the upper magnetic core 51, the same manufacturing process as that of the first embodiment can be performed.

As described above, in the second embodiment, since the resist having poor heat resistance is not used as the constituent material of the head,
Not limited to the magnetic film used this time, any conventionally known film can be used, regardless of whether it is crystalline or amorphous. For example,
Fe-Ga-Si based alloy, Fe-Al-Si based alloy, F
It may be a ferromagnetic metal material such as an e-Ga-Si-Ru-based alloy, a Fe-Al-Ge-based alloy, or a Fe-Ga-Ge-based alloy, or a ferromagnetic amorphous metal alloy, a so-called amorphous alloy. .

In this embodiment, since the coil flattening layer 7 in which the conductor coil 3 is embedded does not use a resist, the heat treatment temperature for obtaining the soft magnetic properties of the lower magnetic core 1 and the upper magnetic core 2 is set. It can be used even for high ones.
Specifically, as the magnetic core 1 and the like, about 350 is conventionally used.
Although it is limited to the one of about 0 ° C., it is possible to use sendust or the like which can obtain soft magnetism by performing a heat treatment of about 500 ° C. Therefore, the usable range of the lower magnetic core 1 and the upper magnetic core 2 constituting the thin film magnetic head can be greatly expanded.

[0086]

As is apparent from the above description, the thin-film magnetic head according to the present invention has a structure in which the lower magnetic core is embedded in the non-magnetic inorganic material layer and is flattened, so that the thin-film magnetic head is heat-resistant. Unlike conventional thin film magnetic heads with inferior resist patterns, the lower magnetic core can effectively suppress the occurrence of a step on the conductor coil formation surface due to the shoulder sag phenomenon.
It can be exposed by being brought into close contact with a photomask.

Therefore, the coil short circuit at the end of the lower magnetic core and the outer circumference of the conductor coil can be suppressed, and the structure is excellent in forming the conductor coil. Further, the flattened structure exhibits an excellent structure for forming a plurality of layers of conductor coils.

When the coil flattening layer made of Al ₂ O ₃ or SiO ₂ is used instead of the conventional coil flattening layer made of a resist, the usable range of the magnetic core can be expanded. Therefore, the degree of freedom in design can be expanded.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing a main part of a thin film magnetic head of a first embodiment to which the present invention is applied.

FIG. 2 shows that the lower magnetic core of the thin film magnetic head is Al ₂ O ₃
FIG. 6 is a front view of the state in which the lower magnetic core is formed, showing the step of being embedded in the film of FIG.

FIG. 3 shows that the lower magnetic core of the thin film magnetic head is Al ₂ O ₃
It shows the process of being embedded in the film of and flattened.
It is a front view of the state in which ₂ O ₃ is formed into a film.

FIG. 4 shows that the lower magnetic core of the thin film magnetic head is Al ₂ O ₃
FIG. 6 is a front view showing a step of being flattened by being embedded in the film of FIG.

FIG. 5: The lower magnetic core of the thin film magnetic head is Al ₂ O ₃
FIG. 6B is a front view showing a step of being embedded in the film of FIG. 4 and being planarized, and showing a state in which the underlying magnetic core is planarized.

FIG. 6 is a perspective view showing a manufacturing process of the thin film magnetic head of the first embodiment, and showing a process of forming Al ₂ O ₃ on the base substrate.

FIG. 7 shows a manufacturing process of the thin film magnetic head,
It is a perspective view which shows the formation process of a lower magnetic core pattern.

FIG. 8 shows a manufacturing process of the thin film magnetic head,
It is a perspective view which shows the formation process of a lower magnetic core pattern.

FIG. 9 is a perspective view showing a step of forming a lower magnetic core of the thin film magnetic head, and showing a step of burying a lower magnetic core pattern in an Al ₂ O ₃ film.

FIG. 10 is a perspective view showing a step of forming a lower magnetic core of the thin film magnetic head, showing a flattening step.

FIG. 11 is a perspective view showing a step of forming a magnetic gap film in the method of manufacturing a thin film magnetic head.

FIG. 12 is a perspective view showing a step of forming a back gap in the method of manufacturing the thin film magnetic head.

FIG. 13 is a perspective view showing a step of forming a first conductor coil in the method of manufacturing the thin film magnetic head.

FIG. 14 is a perspective view showing a step of forming a first coil flattening layer in the method of manufacturing a thin film magnetic head.

FIG. 15 is a perspective view showing a step of forming a second conductor coil in the method of manufacturing the thin film magnetic head.

FIG. 16 is a perspective view showing a step of forming a second coil flattening layer in the method of manufacturing a thin film magnetic head.

FIG. 17 is a perspective view showing a step of forming an upper magnetic core in the method of manufacturing the thin film magnetic head.

FIG. 18 is a perspective view showing a step of forming a copper terminal in the method of manufacturing the thin film magnetic head.

FIG. 19 is a plan view showing a method of manufacturing the thin film magnetic head,
FIG. 3 is a perspective view showing a state where a wafer is completed by forming a film of l ₂ O ₃ and flattening the surface.

FIG. 20 is a perspective view showing a step of forming a first conductor coil in the method of manufacturing the thin-film magnetic head of the second embodiment to which the present invention is applied.

FIG. 21 is a perspective view showing a step of forming a coil contact in the method of manufacturing the thin film magnetic head.

FIG. 22 is a schematic view showing the manufacturing method of the thin film magnetic head, wherein S
It is a perspective view which shows the process of carrying out film-forming and flattening of iO ₂ .

FIG. 23 is a perspective view showing a step of forming a second conductor coil in the method of manufacturing the thin film magnetic head.

FIG. 24 is a perspective view showing a step of forming copper terminals in the method of manufacturing a thin film magnetic head.

FIG. 25 is a schematic view showing the manufacturing method of the thin-film magnetic head, wherein S
It is a perspective view which shows the process of carrying out film-forming and flattening of iO ₂ .

FIG. 26 is a perspective view showing a step of forming a front gap in the method of manufacturing a thin film magnetic head.

FIG. 27 is a perspective view showing a state in which a magnetic gap is formed and a wafer is completed in the method of manufacturing the thin film magnetic head.

FIG. 28 is a cross-sectional view schematically showing a main part of a conventional thin film magnetic head.

FIG. 29 is a perspective view showing a shape of a conductor coil that crosses a lower magnetic core in the conventional thin film magnetic head.

FIG. 30 is a perspective view showing a shape of a conductor coil that crosses a lower magnetic core in the conventional thin film magnetic head.

31 is a cross-sectional view taken along the line AA of FIG. 30.

[Explanation of symbols]

1,51 Lower magnetic core 2,52 Upper magnetic core 3 Conductor coil 3a, 53a First conductor coil 3b, 53b Second conductor coil 4 Base substrate 5 Protective substrate 7 Coil flattening layer 11 Lower magnetic core pattern 13 Al ₂ O ₃ or SiO ₂ film (non-magnetic inorganic insulating material layer) 16 magnetic gap film 17 first coil flattening layer 27 second coil flattening layer G magnetic gap FG Fretont gap BG back gap

[Procedure amendment]

[Submission date] June 29, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

This thin film magnetic head is a magnetic head in which thin film layers such as a magnetic film and an insulating film are laminated in multiple layers and a conductor coil is further formed. This thin-film magnetic head has a unique thin-film patterning method such as film formation, photolithography, etching, plating, lift-off, etc., and is capable of mass-producing wafers with uniform quality. The fact that the magnetic flux is short and the inductance is low is one of the reasons. In response to the recent trend toward higher density, higher performance including materials is being sought.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction content]

In such a thin film magnetic head, for example, as shown in FIG. 28, a lower magnetic core 101 made of permalloy (Ni--Fe) and the like, an upper magnetic core 102, a conductor coil 103 made of Cu and the like and SiO ₂ etc. And a magnetic circuit portion composed of a magnetic gap 106 made of Al ₂ O ₃ -T
It is configured by being sandwiched between a base substrate 104 made of iC, ferrite, etc. and a ceramic-based protective substrate 105.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

For example, as a method of forming the conductor coil 103, there are generally two methods of a flow of film formation-photolithography-etching and a flow of photolithography-plating.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

However, by any of these methods, the above-mentioned conventional thin film magnetic head is used in the lower magnetic core 10.
In the photolithography process of the portion that crosses the end portion of 1, the step is generated in the lower magnetic core 101, and the conductor coil 1
03 pattern defect (short circuit defect) occurs.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction content]

[0017]

In order to achieve the above object, the present inventor has a conductor coil having an upper magnetic core and a lower magnetic core, and a coil flattening layer above the lower magnetic core. In the thin-film magnetic head in which the lower magnetic core is embedded in the non-magnetic inorganic insulating material layer,
It is characterized by being flattened.

[Procedure correction 6]

[Document name to be amended] Statement

[Name of item to be corrected] 0023

[Correction method] Change

[Correction content]

[0023]

According to the thin-film magnetic head of the present invention, since the lower magnetic core has a structure in which it is embedded in a non-magnetic inorganic insulating material layer and planarized, a conventional thin-film magnetic head having a resist pattern having poor heat resistance is arranged. Unlike the above, the lower magnetic core can effectively suppress the occurrence of a step on the surface on which the conductor coil is formed due to the shoulder sag phenomenon. As a result, in the photolithography process, the entire surface on which the conductor coil is formed can be brought into close contact with the photomask for exposure.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

Specifically, the magnetic core is conventionally about 350.degree.
Although it is not limited to the above, it is possible to use sendust or the like that can obtain soft magnetism by performing a heat treatment at about 500 ° C.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Name of item to be corrected] 0030

[Correction method] Change

[Correction content]

In this embodiment, the base substrate 4 is made of Al ₂ O ₃ --TiC as a material from the viewpoint of high thermal conductivity and strength. The base substrate 4 serves as a base for forming individual parts of the magnetic circuit, such as film formation, photolithography, etching, plating, lift-off, and other patterns unique to the thin film.
Actually, four magnetic circuit units are formed on the upper side at a predetermined interval. That is, this embodiment is a multi-channel thin film magnetic head.

[Procedure Amendment 9]

[Document name to be amended] Statement

[Name of item to be corrected] 0045

[Correction method] Change

[Correction content]

The thin-film magnetic head configured as described above is excellent in forming the conductor coil 3 that does not cause a step by flattening the surface on which the conductor coil 13 is formed via the magnetic gap G. This is the structure of a thin film magnetic head. Therefore, in the photolithography process, the entire surface on which the conductor coil 13 is formed can be brought into close contact with the photomask for exposure.

[Procedure Amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0048

[Correction method] Change

[Correction content]

Next, as shown in FIGS. 7 and 8, a lower magnetic film made of an iron-based microcrystalline material is formed to a thickness of, for example, 4 μm by a method of RF sputtering, and a predetermined resist pattern is formed by a photolithography process. Then, the lower magnetic core pattern 11 is formed by etching by ion milling and peeling the resist.

[Procedure Amendment 11]

[Document name to be amended] Statement

[Name of item to be corrected] 0057

[Correction method] Change

[Correction content]

Next, as shown in FIG. 12, a predetermined resist pattern is formed in a photolithography process, and the back gap BG is etched by a technique such as ion milling or reactive ion etching. In this case, the gap film 16 is formed, that is, Si
The lower magnetic core pattern 11 on the back side is exposed by etching O ₂ or Al ₂ O ₃ by 2 μm.

[Procedure Amendment 12]

[Document name to be amended] Statement

[Correction target item name] 0059

[Correction method] Change

[Correction content]

Subsequently, a predetermined resist pattern is formed by a photolithography process, and copper plating of, for example, 4 μm is performed by copper sulfate plating or the like. After that, the resist pattern is peeled off and the underlying Ti / C is formed by ion milling or the like.
When u is etched, the first conductor coil 3a is formed.

[Procedure Amendment 13]

[Document name to be amended] Statement

[Correction target item name] 0061

[Correction method] Change

[Correction content]

Next, as shown in FIG. 14, a predetermined resist pattern is formed by a photolithography process, and a 30
The first flattening layer 17 made of an insulating material is formed by performing heat treatment at about 0 ° C.

[Procedure Amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0065

[Correction method] Change

[Correction content]

In this way, the second-layer conductor coil 3b is formed.
16 is formed, a predetermined resist pattern is formed by a photolithography process as shown in FIG.
The second coil flattening layer 27 made of an insulating material is formed by performing a heat treatment at about ° C.

[Procedure Amendment 15]

[Document name to be amended] Statement

[Correction target item name] 0067

[Correction method] Change

[Correction content]

Next, as shown in FIG. 17, a film of the upper magnetic core 2 made of an iron microcrystalline material is formed to a thickness of, for example, 4 μm by a method such as an RF sputtering method, and a predetermined resist pattern is formed in a photolithography process. The upper magnetic core pattern 12 is formed by forming, etching by a method such as ion milling, and peeling the resist. Above,
The formation of elements that are the elements of the head is almost completed.

[Procedure Amendment 16]

[Document name to be amended] Statement

[Correction target item name] 0069

[Correction method] Change

[Correction content]

First, on the wafer on which the upper magnetic core pattern 12 is formed, for example, Ti is used as a base for terminal plating.
A film of 50 nm / Cu 200 nm is formed by RF sputtering or the like. Subsequently, as shown in FIG. 18, a predetermined resist pattern is formed by a photolithography process, and, for example, 30
Apply μm copper plating. After that, the resist pattern is peeled off and the underlying Ti / Cu is etched by ion milling or the like to form the copper terminal 31.

[Procedure Amendment 17]

[Document name to be amended] Statement

[Correction target item name] 0079

[Correction method] Change

[Correction content]

Then, as shown in FIG. 24, a predetermined resist pattern is formed by a photolithography process and copper plating is performed. After that, the resist pattern is peeled off and the underlying Ti / Cu is etched by ion milling or the like to form the copper terminal 54.

[Procedure 18]

[Document name to be amended] Statement

[Correction target item name] 0081

[Correction method] Change

[Correction content]

Subsequently, as shown in FIGS. 26 and 27,
A predetermined resist pattern is formed by a photolithography process, the flattening layer of the back gap BG is etched by a method such as reactive ion etching or ion milling, the lower magnetic core 51 of this portion is exposed, and the resist is peeled off. Then, a predetermined magnetic path shape is obtained. Through these steps, the wafer 56 of the second embodiment is completed.

[Procedure Amendment 19]

[Document name to be amended] Statement

[Name of item to be corrected] 0083

[Correction method] Change

[Correction content]

In Example 1, the lower magnetic core of Al ₂ O _{3 was used.}
The magnetic gap G formed immediately after planarization by
In the case of the above embodiment, the magnetic gap G must be newly formed because it is lost in the above magnetic path forming step. This is a magnetic gap film 16 made of SiO ₂ or the like.
Is formed by a method such as an RF sputtering method, a predetermined resist pattern is formed in a photolithography process, and the back gap BG is etched by a method such as reactive ion etching or ion milling.
After that, from the formation of the upper magnetic core 51, the same manufacturing process as that of the first embodiment can be performed.

[Procedure amendment 20]

[Document name to be amended] Statement

[Correction target item name] 0084

[Correction method] Change

[Correction content]

As described above, in the second embodiment, since the resist having poor heat resistance is not used as the constituent material of the head,
Not limited to the magnetic film used this time, any conventionally known film can be used, regardless of whether it is crystalline or amorphous. For example, F
e-Ga-Si based alloy, Fe-Al-Si based alloy, Fe
-Ga-Si-Ru-based alloy, Fe-Al-Ge-based alloy,
It may be a ferromagnetic metal material such as an Fe-Ga-Ge-based alloy, or a ferromagnetic amorphous metal alloy, a so-called amorphous alloy.

Claims (6)

[Claims] 1. An upper layer magnetic core and a lower layer magnetic core are provided,
A thin-film magnetic head having a conductor coil formed above a lower magnetic core via a coil flattening layer, wherein the lower magnetic core is embedded in a non-magnetic inorganic insulating material layer and is flattened. Thin film magnetic head. 2. The magnetic head according to claim 1, further comprising a plurality of conductor coils, each conductor coil being flattened by a coil flattening layer. 3. The thin film magnetic head according to claim 1, wherein the non-magnetic inorganic insulating material layer is made of Al ₂ O ₃ or SiO ₂ . 4. A lower magnetic core having a predetermined shape is formed on a substrate, a non-magnetic inorganic insulating material is deposited to cover the lower magnetic core, and the non-magnetic inorganic insulating material is exposed until the lower magnetic core is substantially exposed. Manufacture of a thin film magnetic head, which comprises a step of flattening a material film, a step of forming a conductor coil on the material flattening layer through a coil flattening layer, and a step of forming an upper magnetic core into a predetermined shape. Method. 5. The method of manufacturing a thin film magnetic head according to claim 4, wherein in the step of forming the coil conductor, the plurality of layers of conductor coils are each flattened by a coil flattening layer. 6. The coil flattening layer is made of Al ₂ O ₃ or Si.
6. The method of manufacturing a thin film magnetic head according to claim 4, wherein the film is an O ₂ film.