JPH0481243B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for manufacturing a thin film magnetic head using an amorphous magnetic material as a magnetic layer, and in particular to a method for manufacturing a thin film magnetic head using an amorphous magnetic material as a magnetic layer, in particular a method for manufacturing a thin film magnetic head using an amorphous magnetic material as a magnetic layer, and in particular a method for manufacturing a thin film magnetic head using an amorphous magnetic material as a magnetic layer. A first non-magnetic insulating layer having a thickness equal to the gap length, a conductor layer serving as a winding portion, a second non-magnetic insulating layer, and an upper magnetic layer are formed in sequence on the thin-film magnetic head. Regarding the manufacturing method.

Conventional Structure and Problems Conventionally, it has been proposed to manufacture the magnetic layer of a thin film magnetic head using an amorphous magnetic material by RF sputter deposition, but the following problems have arisen.

Due to the heat generated during production, it is difficult to convert into an amorphous material without sufficient cooling.

In normal sputter deposition, deposition is performed in a vacuum of about 10 ^-2 Torr, so even if the material is made amorphous with an appropriate composition by injecting various gases or oxidizing, it is difficult to obtain sufficient magnetic properties.

Even if an amorphous film with good magnetic properties can be deposited due to its good corrosion resistance, it is difficult to pattern the magnetic layer required for a thin film magnetic head by chemical etching.

If a dry etching method is used for patterning, adverse effects such as crystallization and oxidation due to heating may occur again.

Due to the various problems described above in the prior art, it has been difficult to apply it to thin film magnetic heads despite its good magnetic properties, wear resistance, and corrosion resistance.

OBJECT OF THE INVENTION The present invention aims to solve the problems of the prior art as described above.

The present invention provides a method for manufacturing a magnetic head using an amorphous magnetic material as a magnetic layer, in which the amorphous magnetic layer has little deterioration of magnetic properties due to oxidation, a small temperature rise on the substrate surface, and extremely low crystallization during production. The object of the present invention is to provide a method of forming an amorphous material using a difficult method and thereby obtaining a high-quality amorphous material.

Another object of the present invention is to provide a method for patterning the amorphous magnetic layer without being adversely affected by crystallization and oxidation caused by heating.

Structure of the Invention The method of the present invention comprises forming a lower magnetic layer on a magnetic substrate or a non-magnetic substrate, which becomes the lower magnetic layer, and then forming a first non-magnetic insulating layer having a thickness equal to the gap length, and a winding wire. A method for manufacturing a thin-film magnetic head in which a conductor layer, a second non-magnetic insulating layer, and an upper magnetic layer are sequentially formed. It is characterized in that it is formed as an amorphous magnetic film by sputter deposition using a taring device, and a lift-off method is used as the patterning method.

Embodiments of the Invention FIG. 1 shows an example of a configuration diagram of an ion beam sputtering apparatus used in the present invention. The Ar gas is ionized in the discharge section 1 by the acceleration of thermoelectrons emitted from the W filament 2 by the magnetron 3, and accelerated toward the cathode 4. accelerated
The Ar ⁺ is electrically neutralized to Ar by the neutralizer 5, and is accelerated and sputtered as it is to the sputtering target 7 in the target section 6. The sputtered atoms are deposited on the deposition substrate 8.
At this time, the degree of vacuum in the target section 6 can be maintained to a degree of vacuum of at least 10 ^-5 Torr by using a cryopump. That is, since sputter deposition is performed in a vacuum that is at least 1/1000 times smaller than that of normal RF sputter deposition, a high-quality amorphous film can be obtained that is extremely unaffected by gas infiltration, oxidation, etc. In addition, unlike RF sputter deposition, Ar is not ionized and is in an electrically neutral state, and these beams do not directly touch the deposition substrate, making it possible to suppress crystallization due to temperature rise of the deposition substrate as much as possible. at least 2
In deposition of ~3 μm, an amorphous film can be obtained even without water cooling of the deposition substrate.

The above characteristics of the manufacturing method are extremely advantageous for improving the magnetic properties of an amorphous film by vapor deposition.
RF sputter deposition is usually performed at a vacuum level of about 10 ^-2 Torr. Therefore, the above manufacturing method advantage of this device is that the degree of vacuum near the deposition substrate is
It is thought that this was caused by keeping the temperature below 10 ^-3 Torr during vapor deposition. The induced magnetic anisotropy required for the magnetic layer of the head can be achieved by applying a magnetic field in the required direction as a post-process and performing annealing in the magnetic field.
Alternatively, it can be formed by applying a magnetic field during vapor deposition.

As an example, FIG. 2A shows the B-H curve of a Co--Fe--Nb amorphous film immediately after sputter deposition using an ion beam sputtering apparatus at a vacuum degree of 10 ^-5 Torr near the substrate. No deposition magnetic field was applied to this sample. The film thickness was 2 μm, and no substrate cooling was performed during vapor deposition. Amorphousization of the deposited film has been confirmed at least in the range of X-ray diffraction. On the other hand, this sample was subjected to a magnetic field of several hundred eels under a vacuum of 10 ^-6 Torr.
After heat treatment at 380℃ for 0.5hr, B-
Figure 2B shows the measured H curve. extremely
It can be seen that a good amorphous magnetic film with a small Hc (Hc ~ 0.3 Oe) could be easily formed without cooling. In addition, the initial magnetic permeability (H ~ 1 mOe) of this vapor-deposited sample
Figure 2C shows the frequency characteristics of , and a constant high magnetic permeability of approximately μ1000 is obtained.

Next, a pattern forming method for applying the amorphous magnetic film produced by the ion beam sputtering apparatus to a thin film magnetic head will be described.

In general, amorphous magnetic materials that are to be applied to magnetic heads often have good corrosion resistance, and chemical etching is easily performed after patterning a vapor-deposited film created by the method described above with photoresist. isn't it. Further, even if etching is possible, it is often difficult to perform good patterning. On the other hand, if this is attempted to be done by sputter etching or plasma etching, the etching rate is slow and heat is generated, resulting in the adverse effects of crystallization.

Therefore, in the present invention, a so-called lift-off method is used in which an amorphous film is deposited on a photoresist that has been patterned in advance, and then the deposited film outside the pattern is removed together with the underlying resist layer using an appropriate remover liquid. The amorphous film is then patterned. As an example, a sputtered film (film thickness
2 .mu.m) by the above lift-off method is shown in FIG. 3A. At this time, if the post-baking temperature of the photoresist is too high, the resist will harden significantly together with the heating during the subsequent sputter deposition.
During the subsequent lift-off process, inconveniences may occur such as film residue (indicated by diagonal lines) remaining at the edge of the pattern as shown in Figure 3B, so the post-bake temperature should be kept at a level that does not cause the resist to harden too much. Alternatively, it is appropriate to perform no post-baking after exposing the resist. Due to such consideration, the amorphous amorphous film on the photoresist tends to easily separate during lift-off due to gas generation from the resist during vapor deposition. Further, it is desirable for the resist film thickness to be larger than the vapor deposited film thickness in view of the properties of the lift-off method.

As mentioned above, the lift-off method is not only the most suitable method from the perspective of patterning amorphous amorphous thin films, but also the requirement to enhance the cooling effect, which is essential for creating amorphous as-deposited films, also makes this lift-off method easier. It has a double effect. (Photoresist decomposes at high temperatures). That is, the lift-off method for creating an amorphous vapor deposited film and patterning the vapor deposited film all have common compatible conditions, and the combination of the two can be said to be optimal.

Effects of the Invention The present invention involves sputter-depositing an amorphous magnetic layer of a thin-film magnetic head using an amorphous magnetic material as a magnetic layer at a relatively high degree of vacuum using an ion beam sputtering device, and in patterning the amorphous magnetic layer in advance. By using the lift-off method, which involves vapor deposition on a patterned photoresist, there is little deterioration of magnetic properties due to oxidation, and the temperature rise on the substrate surface is small, making crystallization extremely difficult to occur during fabrication.
Appropriate patterns of magnetic layers of high quality amorphous material can be formed.

Furthermore, since the thin-film magnetic head manufactured by the manufacturing method of the present invention has a high-quality amorphous magnetic layer, it has superior magnetic properties, wear resistance, and corrosion resistance compared to magnetic heads using conventional soft magnetic materials. You can get what you want. In other words, it is possible to prevent the characteristics of the magnetic head from deteriorating due to wear and corrosion of the pole piece that comes into contact with the magnetic recording medium, and by using an amorphous magnetic material with high magnetic flux and high magnetic permeability, it is possible to create a thin film with higher efficiency. A magnetic head can be created.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of sputter deposition using an ion beam sputtering apparatus. Figure 2A
Figure B is the B-H curve of a Co-Fe-Nb amorphous sputtered film (film thickness 2 μm) immediately after deposition, and B is at 380°C.
Amorphous amorphous sputtered film (film thickness 2μm) after heat treatment in a magnetic field (hard magnetization direction) in several hundred Oe for 0.5hr
The B-H curve and C in the same figure are diagrams showing the frequency characteristics of magnetic permeability after heat treatment in a magnetic field. FIG. 3A shows a good lift-off pattern of the amorphous vapor deposited film, and FIG. 3B shows a bad lift-off pattern due to progress in curing of the resist. DESCRIPTION OF SYMBOLS 1... Discharge part, 2... Filament, 3... Magnetron, 4... Cathode, 5... Neutralizer, 6... Target part, 7... Sputter target, 8... Vapor deposition substrate.

Claims (1)

[Scope of Claims] 1. A lower magnetic layer is formed on a magnetic substrate serving as a lower magnetic layer or on a non-magnetic substrate, and a first non-magnetic insulating layer having a thickness corresponding to the gap length, a winding portion and A method for manufacturing a thin film magnetic head by sequentially forming a conductor layer, a second nonmagnetic insulating layer, and an upper magnetic layer, the method comprising forming at least one of the lower magnetic layer and the upper magnetic layer by ion beam sputter deposition. 1. A method of manufacturing a thin film magnetic head, characterized in that an amorphous magnetic film is formed by using a method of forming an amorphous magnetic film, and a lift-off method is used as a patterning method. 2. The method of manufacturing a thin film magnetic head according to claim 1, wherein during the ion beam sputter deposition, the degree of vacuum near the surface of the deposition substrate is set to 10 ^-3 Torr or less. 3. The method of manufacturing a thin film magnetic head according to claim 1, wherein in the lift-off method, the post-baking of the photoresist is kept at a temperature below the curing temperature of the resist, or the post-baking is not performed. 4. The method of manufacturing a thin film magnetic head according to claim 1, wherein the induced magnetic anisotropy of the amorphous magnetic film is formed in an arbitrary direction by heat treatment in a magnetic field as a post-process. 5. The method of manufacturing a thin film magnetic head according to claim 1, wherein the induced magnetic anisotropy of the amorphous magnetic film is formed by vapor deposition in a magnetic field.