JPH08263807A - Formation of magnetic pole of thin-film magnetic head - Google Patents

Abstract

PURPOSE: To make it possible to obtain a thin-film magnetic head which does not adversely affect the distribution of magnetic fields, substantially prevents the occurrence of dimensional defects, facilitate operation by decreasing the number of plating stages and has good characteristics. CONSTITUTION: The magnetic pole 32 of the thin-film magnetic head having a narrow and thin front end 10 of a magnetic pole and a broad and thick yoke part 12 having such a drawn structure which is continuous from this front end of the magnetic pole is formed by a plating method. A magnetic film is formed in the yoke part over the entire part of the front end of the magnetic pole and the yoke part by one time of the plating stage and a resist 34 is patterned thereon exclusive of the front end of the magnetic pole and thereafter, the front end of the magnetic pole is removed to the necessary pole length by an ion milling and is thinly trimmed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a magnetic pole of a thin film magnetic head by a plating method.
The present invention relates to a method of forming a magnetic pole of a thin film magnetic head in which a magnetic film is formed in a yoke portion to a required thickness in one plating step, and a thin magnetic pole tip is formed by partially removing the magnetic film by ion milling.

[0002]

2. Description of the Related Art There are various forms of thin-film magnetic heads for hard disks, and a typical example thereof is to separate magnetic poles of upper and lower two layers provided on a ceramic substrate with a gap film, and to generate a magnetic field and an induced current between them. It is an induction type that forms a coil film for a pickup. In addition, there is an MR composite type that utilizes the MR effect (magnetoresistance effect) for reproduction. In these, the upper and lower magnetic poles are usually made of a plating film of a magnetic material such as permalloy (NiFe alloy), and are formed in a portion defined by a resist with a required thickness.

As shown in FIG. 1, these upper and lower magnetic poles have a narrow and thin magnetic pole tip portion 10 and a wide and thick yoke portion 12 having a diaphragm structure continuous from the magnetic pole tip portion 10. Have. In FIG. 1, A shows the planar shape of the magnetic pole, and B shows its cross-sectional shape. here,
The reason why the yoke portion 12 is made thick is to prevent magnetic saturation, and this thick portion is also called “futonashi”.
Typical dimensions are a = 200 μm, b = 150 μm,
The values are c = 100 μm, d = 4 μm, e = 5 μm. Note that the dimension e corresponds to the pole length PL, the symbol GD is the gap depth, and TW is the track width. Finally, in order to obtain a predetermined gap depth GD,
The polishing will be performed up to the position of the symbol FS indicated by the virtual line.
The position of this FS coincides with the air bearing surface of the slider.

By the way, the magnetic pole having such a structure has been conventionally used in two cases.
It was formed by repeating the plating process once. First, as shown in FIG. 3A, the resist 20 is patterned for the first time around the portion where the magnetic pole is formed, and the first plating is performed to form the magnetic film 22. The plating thickness e is selected so as to have a film thickness (pole length PL) necessary for the tip of the magnetic pole. Next, as shown in FIG. 3B, the resist 24 is patterned again so as to surround the yoke portion, and second plating is performed to form a magnetic film 26 having a thickness d. The second magnetic film 26 is a so-called “flatter”, and the total (d + e) of the first and second magnetic films 22 and 26 is a thick yoke portion. Thereafter, as shown in FIG. 3C, the resist 24 is removed to obtain a necessary magnetic film.

[0005]

As described above, in the conventional method, the step of forming the magnetic film by plating must be performed twice. However, if the plating is performed in two steps, problems such as non-uniform composition or discontinuity in shape (that is, generation of step 28 as shown in FIG. 3) may occur. If the composition is not uniform between the first layer and the second layer, the predetermined output may not be obtained because the distribution of the magnetic field differs on the boundary surface. Further, if the shape is discontinuous, problems such as dimensional failure and adversely affecting the distribution of the magnetic field occur.

An object of the present invention is to solve the problems caused by two plating steps, to prevent dimensional defects from occurring, to reduce the number of plating steps to facilitate the work, and to obtain a thin film magnetic head having good characteristics. To provide a method of forming a magnetic pole.

[0007]

SUMMARY OF THE INVENTION The present invention provides a magnetic pole of a thin film magnetic head having a narrow and thin magnetic pole tip portion and a wide and thick yoke portion having a diaphragm structure continuous from the magnetic pole tip portion. It is a method of forming by a plating method. In the present invention, a magnetic film is formed over the entire magnetic pole tip portion and the yoke portion to a required thickness in the yoke portion by a single plating process, a resist is patterned on the magnetic film excluding the magnetic pole tip portion, and then ion milling is performed. The tip of the magnetic pole is removed to the required pole length and thinly trimmed.

[0008]

In the method of the present invention, the plating process is completed only once for forming the magnetic poles of the thin film magnetic head. Therefore, it is possible to form a magnetic pole having a desired shape without causing a uniform plating composition and discontinuity in shape. The thickness of the magnetic pole is adjusted accurately by trimming the tip of the magnetic pole to be thinned by ion milling and removing a part.

[0009]

FIG. 2 shows steps of a method of forming a magnetic pole of a thin film magnetic head according to the present invention. First, the magnetic pole forming portion is defined by patterning the resist 30, and, for example, permalloy (N
1 by plating a magnetic material such as an iFe alloy)
The magnetic film 32 having a thickness required for the yoke portion in one plating process
To form. In other words, the magnetic film 32 has a thickness (that is, d + e = 9 μm in the above dimensional example) that includes the conventional “flatter” in one plating step. Therefore,
The entire magnetic film 32 including the magnetic pole tip and the yoke has the same thickness of 9 μm (see A in FIG. 2).

Next, the resist 34 is patterned except for the magnetic pole tip portion to be thinned, and the magnetic film at the magnetic pole tip portion is made to have a desired thickness (e = e in the example of the above dimension) by an ion milling method.
5 μm) to make thin (see B in FIG. 2). The removed portion is represented by a broken line and the symbol R is attached. By such trimming by ion milling, the pole length PL at the tip of the magnetic pole and the thickness of the front portion of the yoke portion (magnetic pole diaphragm structure) can be determined. Then, when the resist is finally removed, only the magnetic film having steps is left (see C in FIG. 2). As a result, a magnetic pole of a thin film magnetic head having a thin magnetic pole tip portion 10 and a thick yoke portion 12 is obtained.

In the prior art, an ion milling process may be provided after the plating process, but this is to remove the plating residue, and is different from the process of thinly trimming the magnetic film as in the present invention. Totally different.

According to the method of the present invention, a magnetic pole having a desired thickness distribution can be formed. The method of the present invention can be applied to the formation of the lower magnetic pole and the lower magnetic pole of the thin film magnetic head.

[0013]

As described above, according to the present invention, since it is not necessary to perform the plating process twice, and even the "flatter" of the yoke portion can be formed by only one plating process, uneven plating composition and Problems (that is, deterioration of characteristics, dimensional defects, etc.) due to discontinuity of shape do not occur. Further, since the number of plating steps is reduced, the manufacturing becomes easier accordingly.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example of the shape of a magnetic pole of a thin film magnetic head.

FIG. 2 is a process explanatory diagram of a magnetic pole forming method according to the present invention.

FIG. 3 is a process explanatory diagram of a conventional magnetic pole forming method.

[Explanation of symbols]

 10 magnetic pole tip 12 yoke part 30 resist 32 magnetic film 34 resist

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiya Suzuki 5-36-11 Shinbashi, Minato-ku, Tokyo Fuji Electric Chemical Co., Ltd. (72) Shunsuke Haga 5-36-11 Shinbashi, Minato-ku, Tokyo Fuji Electric Chemical Co., Ltd.

Claims (1)

[Claims] 1. A method for forming a magnetic pole of a thin-film magnetic head having a narrow and thin magnetic pole tip portion and a wide and thick yoke portion having a diaphragm structure continuous from the magnetic pole tip portion by a plating method. A magnetic film is formed over the entire magnetic pole tip portion and the yoke portion by a single plating process to a required thickness in the yoke portion, and after patterning the resist except the magnetic pole tip portion, the magnetic pole tip portion is removed by ion milling. A method of forming a magnetic pole of a thin film magnetic head, which comprises removing a required pole length and thinly trimming.