JPH0620230A - Thin-film magnetic head and its manufacture - Google Patents

Abstract

(57) [Abstract] [Purpose] To form an insulating layer that can withstand a temperature rise during magnetic film formation and annealing. [Structure] An organic silicone resin is used instead of a photoresist in an insulating layer of a thin film magnetic head. After heat-curing at 350 ° C., a silicone resin is patterned into an insulating layer by plasma of freon and oxygen before use. At this time, a protective sacrificial layer having a different etching characteristic from the gap thin film may be formed on the gap thin film, and then the insulating layer may be formed (silicon etching).

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 a method of manufacturing the same, and more particularly to a thin film magnetic head having an improved insulating layer between a magnetic core and a coil and having excellent magnetic recording characteristics and reproducing efficiency, and a method of manufacturing the same.

[0002]

2. Description of the Related Art A thin-film magnetic head is manufactured with a film forming technique such as a vapor deposition method and a sputtering method, a lithography technique such as a photoengraving technique, and an etching technique, which is similar to a semiconductor integrated circuit. Is characterized in that it can be mass-produced in batch.

4A to 4F show, for example, JP-A-55-8.
It is sectional explanatory drawing which shows the manufacturing method of the thin film magnetic head shown by the 4019 publication. In FIG. 4, 1 is a substrate, 2 is a substrate protective film, 3 is a lower magnetic core, 4 is a magnetic gap, 5 is a first insulating layer, 6 is a copper coil, 7 is a second insulating layer, 8 is an upper magnetic core, and 9 is. Is an insulating protective film.

Next, the manufacturing method and operation of the thin film magnetic head shown in FIG. 4 will be described. First, the substrate protective film 2, the lower magnetic core 3, and the magnetic gap 4 are formed on the substrate 1 (a in FIG. 3). The magnetic gap 4 is an inorganic insulating sputtered film such as alumina. A photoresist is used to form the shape of the lower insulating layer 5 on this layer by a lithographic technique. The photoresist is heat-cured at 200 to 250 ° C. (FIG. 3b). Then, after the copper coil 6 is formed, the upper insulating layer 7 is formed of photoresist by the same method as the lower insulating layer 5 (c in FIG. 3). Subsequently, the upper magnetic core 8 is formed (d in FIG. 3). The copper coil 6, the lower magnetic core 4, and the upper magnetic core 8 are formed by pattern plating. Next, the insulating protection layer 9 is formed and polished (e in FIG. 3). Then, the lapping process is performed until the core tip is exposed (f in FIG. 3).

The thin film magnetic head manufacturing method described above has an advantage over the conventional bulk type magnetic head manufacturing method in that the magnetic core and the coil winding can be collectively formed for each substrate.

[0006]

However, in the method of manufacturing a thin film magnetic head as described above, the material of the magnetic core that can be used is limited because the formation of the magnetic core is performed by the plating method, and a material having more excellent magnetic characteristics is used. Can't use. That is, in forming the magnetic core, film formation by a dry film formation method such as a sputtering method, which has a wider range of material selection than the plating method, is effective.

On the other hand, on the other hand, when the magnetic core is formed by the dry film forming method such as the sputtering method by the method shown in FIG. 4, the temperature rises when forming the magnetic thin film for the upper magnetic core and the magnetic characteristics are improved. However, there is a problem that the photoresist is cracked by the heat treatment performed as necessary, and the gas generated from the resist causes the magnetic film to float and peel off.

Although the photoresist is used after being hardened by heating, the thermal decomposition of the photoresist becomes remarkable at 250 ° C. or higher. Therefore, for example, the temperature of 250 ° C. or higher may be applied to the magnetic film for the magnetic core, if necessary. There is a problem that heat treatment is difficult.

The present invention has been made to solve the above problems, and a thin film magnetic head having a good shape can be obtained by using an organic insulating layer capable of using a dry film forming method. An object of the present invention is to provide a method of manufacturing a magnetic head, a thin film magnetic head having excellent magnetic recording characteristics and reproducing efficiency.

[0010]

A thin film magnetic head of the present invention electrically insulates upper and lower thin film magnetic cores formed on a substrate, a thin film conductor coil, a gap thin film, and the coil and the magnetic core. A thin film magnetic head having an insulating layer, wherein the insulating layer is made of an organic silicone resin having a ladder structure containing silicon, oxygen and carbon as main components, a photoresist is used as a mask for etching, CF ₄ , S
It is characterized in that it is formed by etching into an insulating layer shape by plasma of freon containing at least one selected from the group consisting of F ₆ and CHF ₃ and oxygen, and then the photoresist of the mask is removed by ashing. .

The method of manufacturing the thin film magnetic head of the present invention is the method of manufacturing the thin film magnetic head, wherein a protective sacrificial layer having an etching characteristic different from that of the gap thin film is formed on the gap thin film to prevent the gap thin film from being etched. The feature is that the film thickness of the gap thin film is easily controlled. In addition, before patterning the organic silicone resin, an inorganic thin film containing a silicon element for enhancing adhesion is formed and then an insulating layer is formed, and the adhesion enhancing film is removed before forming the upper magnetic core. Is characterized by. In addition, a lower thin film magnetic core, a thin film conductive coil, and an insulating layer that electrically insulates the magnetic core from the coil are formed, and subsequently, a gap thin film is formed and then an upper magnetic core is formed. There is. further,
The mask resist is ashed by oxygen plasma,
The feature is that ashing is subsequently performed by an ion beam.

[0012]

Since the method of manufacturing the thin film magnetic head according to the present invention is configured as described above, the temperature rise during the formation of the magnetic film for the upper magnetic core and the heat treatment which is carried out as necessary for improving the magnetic characteristics. Thus, the insulating layer is formed without cracks or peeling.

Further, since the heat resistant temperature of the insulating layer is improved and the annealing temperature range of the magnetic film is expanded, a magnetic core material having more excellent magnetic characteristics can be used.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the thin film magnetic head of the present invention and its manufacturing method will be explained with reference to the accompanying drawings.

[Embodiment 1] FIG. 1 is a sectional explanatory view showing an embodiment of a method of manufacturing a thin film magnetic head according to the present invention. 1 to 9 are the same as those in the conventional manufacturing method, and 10 is a protective sacrifice. Layer, 10a is an adhesion enhancing film of silicone, 11 is silicone for insulating layer, 12 is photoresist for mask, 1
Reference numeral 3 is plasma of freon and oxygen, 14 is plasma of oxygen, 15 is a silicone insulating layer on the coil, and 16 is plasma for etching the sacrificial layer.

First, the substrate protective film 2, the lower magnetic core 3 and the magnetic gap film 4 are formed on the substrate 1 (a in FIG. 1). As the magnetic gap 4, Al ₂ O ₃ is used, for example. Next, a protective sacrificial layer 10 having an etching characteristic different from that of the magnetic gap film is formed by a method such as a sputtering method. The protective sacrificial layer 10 plays a role of protecting the magnetic gap film during silicone etching, and it is preferable to use a metal film that is hardly etched by plasma of freon and oxygen. When the protective sacrificial layer 10 is not removed before forming the upper core and is used as a part of the gap film, a metal film such as Cu or Cr which is a non-magnetic metal film is used to protect before forming the upper core. When the sacrificial layer 10 is removed, a magnetic film such as permalloy may be used. Alternatively, a non-magnetic metal film such as Cu or Cr is provided directly on the lower magnetic core 3 without forming Al ₂ O ₃ as a magnetic gap film to serve as both a protective sacrificial layer and a magnetic gap film. You may form. The protective sacrificial layer 10 may be formed on the entire surface of the wafer, or only the magnetic gap portion may be left and the rest may be removed. A silicon adhesion enhancing film 10a is formed thereon by a sputtering method or the like (FIG. 1b). The adhesion-strengthening film 10a is preferably SiO ₂ or Si ₃ N ₄ composed of a silicon element contained in an organic silicone resin. Although the thickness of the adhesion enhancing film 10a depends on the thickness of the lower magnetic core 3, it is usually about 1 to 2 μm.

Next, the organic silicone resin 11 is spin-coated by a spinner and heated in vacuum for 3 hours or more to 3 times.
The temperature is raised to 50 ° C., and heat curing is carried out with a holding time of 1 hour (c in FIG. 1). Then, the photoresist 12 is formed in the shape of the insulating layer by using the photoengraving technique (d in FIG. 1). Then, the silicone resin is exposed to the plasma 13 containing oxygen and freon to etch the shape of the first insulating layer (e in FIG. 1).
When the plasma 13 is CF ₄ and O ₂ , for example, the proportion of O ₂ is 5 to 60% (volume%).

Subsequently, the mask photoresist is ashed by oxygen plasma 14 (f in FIG. 1). Since the etching rate of the photoresist by oxygen is 10 times or more that of silicone, it is possible to overetch the silicone after ashing the photoresist. If the mask photoresist is peeled off using a resist peeling solution such as acetone instead of ashing, the silicone resin will be cracked, which is not suitable for patterning.

Next, the copper coil 6 is formed, and the second insulating layer 15 is formed in the same manner as the silicone resin 11 is formed into an insulating layer shape (g in FIG. 1). At this time, the photoresist is left. The thickness of the remaining photoresist depends on the film thickness of the adhesion enhancing film 10a, but is several μm. The exposed portion of the adhesion enhancing film 10a and the rest of the mask photoresist are etched by the plasma 16 for etching (h in FIG. 1). The plasma 16 is, for example, C
In the case of F ₄ and O ₂ , O ₂ is 5 to 60% (volume%).

Next, the protective sacrificial layer 10 is removed. At this time, when removing the protective sacrificial layer 10 existing only in the magnetic gap portion, it is removed by wet etching, and when removing the protective sacrificial layer 10 existing on the entire surface of the wafer, it is removed by an ion beam. Then, the upper magnetic core 8 and the insulating protection film 9 are formed and polished (i in FIG. 1). When forming the upper magnetic core, a heat treatment for improving magnetic characteristics is performed if necessary.

Since the organosilicone resin has higher heat resistance than the conventionally used photoresist, the temperature rise during the formation of the magnetic thin film for the upper magnetic core and the heat treatment carried out as necessary to improve the magnetic characteristics, The insulating layer is not cracked or the magnetic film is not lifted and peeled off. Further, since the heat treatment temperature range of the magnetic thin film is expanded, the magnetic properties of the magnetic film are improved and the material selection range of the magnetic thin film is expanded. In addition, since the organic silicone resin has higher moisture resistance than photoresist, long-term reliability is improved.

[Embodiment 2] FIG. 2 is a sectional explanatory view showing another embodiment of the method of manufacturing the thin film magnetic head of the present invention.
6 is the same as that of the first embodiment, and 10b is a film for protecting the magnetic core and enhancing silicone adhesion. Unlike the first embodiment, the upper magnetic core does not come into contact with the organic silicone resin, so if the adhesion between the magnetic film and silicone is poor, or if the original magnetic properties of the magnetic film are not exhibited, the adhesion is improved. Properties and magnetic properties can be improved.

First, a substrate protective film 2, a lower magnetic core 3 and, if necessary, a protective layer 10b for protecting the lower magnetic core 3 and enhancing the adhesion are formed on the substrate 1 (a in FIG. 2). . Then, the organic silicone resin 11 is spin-coated by a spinner (b in FIG. 2), and the photoresist 12 is formed in the shape of an insulating layer by the photolithography technique (c in FIG. 2).

Next, plasma 13 containing freon and oxygen
To expose the silicone resin to the desired shape (FIG. 2d). Then, the mask resist is ashed by oxygen plasma 14 (e in FIG. 2). Next, the second insulating layer 15 is formed in the same manner as the copper coil 6 and the silicone resin 11 are formed in the insulating layer shape (f in FIG. 2). After that, the film 10b for protecting the magnetic core and enhancing the silicone adhesion is etched by the plasma 16 (g in FIG. 2). Freon and oxygen plasmas 13 and 1
6 is the same as in the first embodiment.

After forming the gap film 4 (h in FIG. 2), the upper magnetic core 8 and the insulating protection film 9 are formed and polished (i in FIG. 2). When forming the upper magnetic core, a heat treatment for improving magnetic characteristics is performed if necessary.

[Embodiment 3] FIG. 3 is a cross sectional view showing still another embodiment of the method of manufacturing the thin film magnetic head of the present invention.
1 to 16 are the same as those in the first embodiment, and 17 is an ion beam. In this embodiment, instead of ashing the photoresist for the mask only with oxygen plasma,
By performing ashing with oxygen plasma and then ashing with an ion beam, the shape of the resist pattern surface is transferred as it is, and a smooth silicone pattern surface is obtained without any change in the shape under the silicone pattern.

First, the substrate protective film 2, the lower magnetic core 3, and the gap thin film 4 are formed on the substrate 1 (a in FIG. 3). Then, the magnetic gap film 4, the protective sacrificial layer 10 and the adhesion enhancing film 10a are formed in the same manner as in Example 1 (b in FIG. 3).

Next, an organic silicone is applied by spin coating (c in FIG. 3), and a photoresist 12 is formed in the shape of an insulating layer by photolithography (d in FIG. 1). At this time, the film thickness of the photoresist is larger than that in the first embodiment.

Then, the silicone resin is etched into a desired shape by exposing it to the plasma 13 containing oxygen and freon (e in FIG. 1). Then, the mask resist is ashed by oxygen plasma 14 (f in FIG. 1). Since the film thickness of the photoresist is larger than that of the first embodiment, the photoresist remains slightly on the silicone pattern, and this residue is removed by the ion beam 17 (g in FIG. 3). The upper insulating layer 15 is formed in the same manner as the copper coil 6 and the silicone resin 11 are formed into an insulating layer shape (h in FIG. 3). The shape of the resist pattern surface is transferred as it is by using the ion beam 17 rather than by ashing the entire resist by the oxygen plasma 14, and a smooth silicone pattern surface is obtained without being affected by the change in the shape under the silicone pattern. This is particularly effective for improving the magnetic characteristics of the magnetic film when forming the upper insulating layer 15. The protective sacrificial layer 10 and the adhesion enhancing film 10a are removed by the same method as in Example 1 (i in FIG. 3). The upper magnetic core 8 and the insulating protective film 9 are formed and polished (j in FIG. 3). When forming the upper magnetic core, a heat treatment for improving magnetic characteristics is performed if necessary.

When the adhesion enhancing film is formed in Examples 1 to 3 as long as the film thickness is sufficient to electrically insulate the lower magnetic core and the conductor coil, the first layer The eye silicone insulating layer is not necessary, and the conductor coil may be formed immediately above the adhesion enhancing film.

Further, the conductor coil is not limited to one layer and may be two or more layers.

[0032]

As is clear from the above description, according to the method of manufacturing the thin film magnetic head of the present invention, the interlayer insulating layer between the magnetic core and the coil can be easily formed, and the magnetic film can be formed by the dry film forming method. It is possible to obtain a thin film magnetic head having excellent recording characteristics and reproducing efficiency, which is extremely effective in practical use.

[Brief description of drawings]

FIG. 1 is an explanatory cross-sectional view of an example of a method of manufacturing a thin film magnetic head of the present invention.

FIG. 2 is a sectional explanatory view of another embodiment of the method of manufacturing the thin film magnetic head of the invention.

FIG. 3 is a cross-sectional explanatory view of still another embodiment of the method of manufacturing the thin film magnetic head of the present invention.

FIG. 4 is a cross-sectional explanatory view of a conventional method of manufacturing a thin film magnetic head.

[Explanation of symbols]

 1 Substrate 2 Substrate Protective Film 3 Lower Magnetic Core 4 Magnetic Gap 5 First Insulating Layer by Photoresist 6 First Coil 7 Second Insulating Layer by Photoresist 8 Upper Magnetic Core 9 Insulating Protective Film 10 Protective Sacrificial Layer 10a Adhesion Strengthening of Silicone Film 10b Film for protection of magnetic core and silicone adhesion enhancement 11 Silicone resin 12 Mask resist 13 Freon and oxygen plasma 14 Oxygen plasma 15 Upper insulating layer by silicone 16 Adhesion enhancement film etching plasma 17 Ion beam

Claims (5)

[Claims] 1. A thin-film magnetic head having upper and lower thin-film magnetic cores formed on a substrate, a thin-film conductor coil, a gap thin film, and an insulating layer electrically insulating the coil and the magnetic core, The insulating layer is made of an organic silicone resin having a ladder structure containing silicon, oxygen and carbon as main components, a photoresist is used as an etching mask, and at least one selected from the group consisting of CF ₄ , SF ₆ and CHF _3. A thin film magnetic head characterized by being formed by etching into an insulating layer shape by plasma of one kind of freons and oxygen, and then removing the photoresist of the mask by ashing. 2. The method of manufacturing a thin film magnetic head according to claim 1, wherein a protective sacrificial layer having etching characteristics different from those of the gap thin film is formed on the gap thin film to prevent etching of the gap thin film. A method of manufacturing a thin film magnetic head, characterized in that the film thickness is easily controlled. 3. A method of manufacturing a thin-film magnetic head according to claim 1, wherein before patterning the organic silicone resin,
A method of manufacturing a thin film magnetic head, comprising forming an inorganic thin film containing a silicon element for enhancing adhesion, forming an insulating layer, and removing the adhesion enhancing film before forming an upper magnetic core. 4. The method of manufacturing a thin film magnetic head according to claim 1, wherein a lower thin film magnetic core, a thin film conductive coil, and an insulating layer for electrically insulating the magnetic core and the coil are formed, and subsequently, A method of manufacturing a thin film magnetic core, which comprises forming a gap thin film and then forming an upper magnetic core. 5. The method of manufacturing a thin-film magnetic head according to claim 1, wherein the mask resist is ashed by oxygen plasma, and then ashing is performed by an ion beam.