JPH09147321A - Thin film magnetic head and method of manufacturing the same - Google Patents

Abstract

(57) Abstract: A gap depth management pattern having high accuracy and excellent visibility is simply formed without complicating the process. SOLUTION: Markers 26, 28 for gap depth management
Are formed on both sides of the magnetic pole 24 symmetrically along the head shape at the same time as the coil. The thin film magnetic head element is polished perpendicularly to the magnetic pole center 24C from the polishing surface 30 side. Position P
Markers 26 and 28 are polished as 1, P2 and P3.
The interval W becomes open. Interval W between markers 26 and 28
And the gap depth L are expressed by a simple relationship, and the gap L can be easily obtained from the marker interval W. Since the markers 26 and 28 are continuously formed, the marker interval W continuously increases as the polishing progresses, so that the gap depth L can be continuously and favorably adjusted.

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 used in, for example, a VTR and a manufacturing method thereof.
More specifically, it relates to improvement of the gap depth management pattern.

[0002]

2. Description of the Related Art With the demand for higher density magnetic recording, miniaturization of magnetic heads has progressed, and thin film magnetic heads have been developed. The thin-film magnetic head has many advantages such as being able to simultaneously form a large number of heads having a minute pattern by applying the conventional semiconductor manufacturing technology and manufacturing a multi-track head at a relatively low cost. The gap depth of this thin-film magnetic head is determined by polishing, but since the gap depth greatly affects the electromagnetic conversion efficiency and life of the magnetic head, improvement of gap depth finishing accuracy is an issue.

Normally, a gap depth control pattern (hereinafter referred to as "marker") for detecting the polishing amount is formed adjacent to the thin film head (track) pattern in the vicinity of the magnetic pole tip, and the head pattern and the marker are formed. Polish the composite.
Then, by observing the marker from the polished surface, the desired magnetic gap depth is obtained. As a material used for the marker, a metal film is often used in order to improve the visibility when viewed with an optical microscope. For example, Japanese Unexamined Patent Publication No. 61-267913 discloses an example of a pair of triangular markers displaced by 180 °. Japanese Patent Laid-Open Nos. 62-232718 and 22219 disclose 2
A thin film magnetic head having two depth detecting markers is disclosed. Japanese Patent Laid-Open No. 63-34713 discloses a head manufacturing method using a polishing control mark.

However, such a method requires a step for forming and processing a film that serves as a marker, which is costly and time consuming. If the marker is made of a thin film in order to improve the processing accuracy, there is a problem that the visibility of the marker from the polished surface is deteriorated.

As another background art, there is a method of simultaneously forming a marker when the magnetic core is formed by etching such as an ion beam method. According to this method, since the marker can be formed in the same step as the magnetic core, the step does not become complicated. However, there are some unfavorable aspects when applied to, for example, a video head. In a video head, the head wears due to sliding with the tape, so the wear amount is taken into consideration. For example, when compared with a HDD head that is not in contact with the medium, the video head is used with a large gap depth. In this case, the magnetic pole is made thick in order to prevent magnetic saturation at the magnetic pole tip. However, if such a thick magnetic pole is used, the machining accuracy of the marker becomes low, and it becomes difficult to control the gap depth.

Furthermore, when the sliding width of the tip of the element is processed by the ion beam etching method, both sides of the tip of the magnetic pole,
That is, since there is no space on the left and right sides of the portion corresponding to the track when the element is viewed from above, it is necessary to place the marker considerably close to the magnetic pole. However, if the magnetic pole pattern and the marker pattern are too close to each other, there is a disadvantage that a film remains between the patterns when etching is performed.

The present invention focuses on these points.
It is an object of the present invention to easily form a gap depth management pattern with high accuracy and excellent visibility without complicating the process.

[0008]

To achieve the above object, the present invention provides a magnetic pole (24) around which a coil (18) is wound.
In a thin film magnetic head (10) formed on a substrate (80) with a gap layer (82) sandwiched between the magnetic poles (24), a gap depth management pattern non-parallel to the gap depth direction. (26,28) is formed. Another invention is the pattern for managing the gap depth (26, 28).
Are formed along the head shape symmetrically with respect to the magnetic pole center (24C). Yet another invention is a method of manufacturing the thin-film magnetic head, comprising the coil (18).
When the pattern is manufactured, the gap depth management pattern (26, 28) is formed by using a material (56) different from the surrounding material.

The main aspects of the present invention include the following. (1) A gap depth control pattern is formed by etching an insulating film and burying a different film in the etched portion. (2) In the thin film magnetic head of (1) above, the formation of the gap depth control pattern is performed simultaneously in the coil manufacturing process. (3) Gap depth management patterns are arranged in a line that is not parallel to the gap depth direction of the thin film magnetic head and has a constant width, and is symmetrical about the center line of the thin film magnetic head. The above and other objects, features and advantages of the present invention will be apparent from the following detailed description and the accompanying drawings.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to Examples. First, FIG.
The outline of the thin film magnetic head element according to the present embodiment will be described with reference to FIG. In the figure, the sliding width of the tip portion 12 of the element 10 is WA and the element width of the rear end portion 14 is WB. A magnetic pole portion 16 is formed at the center of the tip portion 12, and a spiral coil 18 is formed between the upper and lower magnetic pole layers. Both ends of the coil 18 are extended toward the element rear end portion 14 by lead wires 20 and 22. Further, in this embodiment, markers 26 and 28 are formed on both sides of the magnetic pole 24 at the tip of the magnetic pole portion 16.

FIG. 1 shows an enlarged view of the tip portion 12 of the element 10 before polishing. The magnetic pole 24 has a polishing surface 30.
And the width WC is the track width for signal recording. Centers 26C and 28C of the markers 26 and 28
Are symmetrically formed in the direction of an angle θ with respect to the center 24C (track center) of the magnetic pole 24. Gap depth L
Is the length from the position PQ of the bottom portion 32 where the magnetic pole 24 spreads in a fan shape to the polishing surface 30. The center of the track is polished 24
Performed perpendicular to C. For example, when polishing is performed up to the position PA, the gap depth L is the length from PQ to PA.

At the bottom position PQ, the distance between the magnetic pole center 24C and the marker center 28C is DQ. Magnetic pole center 2
The same applies to the distance between 4C and the marker center 26C. Therefore, the distance W between the marker centers 26C and 28C at the bottom position PQ is 2DQ. On the other hand, at the position PA, the distance between the magnetic pole center 24C and the marker center 28C is DA, so the distance W between the marker centers 26C and 28C is 2DA.
For example, if the angle θ of the markers 26, 28 with respect to the magnetic pole center 24C is 45 °, the DQ becomes 30 μm, and the intersection point P of the marker centers 26C, 28C from this bottom position PQ.
The distance DX to X is also 30 μm.

Next, such markers 26 and 28 are formed simultaneously with the coil 18 shown in FIG. The basic steps will be described with reference to FIG. 3. First, a resist pattern 54 corresponding to the coil 18 and the markers 26 and 28 is formed on an insulating film 52 such as SiO2 or TiO2 formed on a substrate 50. (See Figure (A)). Incidentally, the coil portion is mainly shown in FIG. Then, in this state, the insulating film 52 is etched by a method such as reactive ion etching (RIE) (see FIG. 6B). Since the etching depth at this time corresponds to the thickness of the markers 26 and 28, the etching is performed to some extent deep to improve the visibility when polishing. For example, the etching depth is on the order of several μm.

Next, the resist film 54 is removed, and a metal film 56 of Cu, Au, Al, Ti, W, etc. is removed.
It is formed by a method such as vacuum deposition or sputtering (see Fig. (C)). The metal film 56 may be formed to have the same depth as the etched depth or a slightly thicker thickness. Next, the metal film adhered to a portion other than the required pattern is removed by polishing (see FIG. 3D).

Through the above steps, a desired pattern of the metal film 56 can be embedded and formed in the insulating film 52.
Note that RIE has relatively high precision and can finely process a thick insulating film. Therefore, a fine line-shaped pattern can be processed, and as a result, a highly accurate marker pattern can be formed, and further, highly accurate gap depth processing can be performed.

As described above, according to this embodiment, the coil 1
By adding the marker pattern to the photomask for forming 8, the markers 26 and 28 and the coil 18 can be easily formed in the same step, and the step of forming the marker does not complicate the step.

Next, the operation of this embodiment will be described. In addition,
FIG. 4 shows a state of the polished surface, in which insulating layers 84 and 86 on the substrate 80 sandwich the gap layer 82 to form the magnetic pole 24 by the upper magnetic pole layer 24A and the lower magnetic pole layer 24B. Has become. Then, these upper magnetic pole layers 24A
Markers 26 and 28 are formed on both wings of each.

As mentioned above, the element 10 has a polishing surface 30.
Polished from the side perpendicular to the magnetic pole center 24C. For example, when polishing is performed up to the position P1 shown in FIG. 1, the polishing surface at this time is as shown in FIG. 4 (A). In this polishing position, the markers 26 and 28 are located near the magnetic pole 24. When polishing is further performed to the position P2 = PA, the result is as shown in FIG. 4 (B), and the distance between the markers 26 and 28 is increased. If further polishing is performed to the position P3 = PQ, the polishing surface at this time becomes as shown in FIG. 4 (C),
The distance between the markers 26 and 28 is further increased.

The gap W between the markers 26 and 28 and the gap depth L are expressed by a simple relation, and the gap L can be easily obtained from the gap W of the markers. For example, when θ = 45 ° and DQ = DX = 30 μm, if W = 20 μm, L
= 20 μm, and if W = 40 μm, L = 10 μm. Of course, the gap L can be similarly measured for other values of the interval W. Further, since the markers 26 and 28 are continuously formed, the marker interval W continuously increases as the polishing progresses, so that the gap depth L can be continuously and favorably adjusted.

As described above, according to this embodiment, the gap depth can be accurately known by measuring the interval between the markers formed with high accuracy without complicating the process. Moreover, since the metal of the different type of film is used as the marker, it can be clearly distinguished from the surrounding materials and the visibility is also good. Further, since the marker is composed of only two line patterns, its occupied area can be small. Further, in the video head, in order to improve the contact state with the medium, as shown in FIG. 2, the tip of the element is often processed into a convex shape or a convex shape, and the sliding width WA is Get smaller. However, even in such a case, according to the present embodiment, the markers 26 and 28 are not lost, and good gap depth management is possible.

The present invention can be variously modified based on the above disclosure, and includes the following, for example. (1) In the above embodiment, the angle θ of the marker center with respect to the magnetic pole center (track center) is set to 45 °, but it may be appropriately set if necessary. Further, it does not prevent the marker from being non-linear.

(2) In the above embodiment, the marker arrangement is symmetrical so that an acute angle is formed toward the magnetic pole tip, but it does not prevent the marker from being asymmetric. For example, one of them is formed in parallel along the magnetic pole center. (3) In addition, the present invention is not limited to the numerical values, shapes, materials and the like shown in the above embodiment. Any type of thin film magnetic head can be applied.

[0023]

As described above, the present invention has the following effects. (1) Since the gap depth management pattern is formed of a different material in a direction not parallel to the gap depth direction, the gap depth can be managed with high accuracy and good visibility. (2) Since the gap depth management pattern is formed at the same time as the coil pattern, complication of the process is prevented.

[Brief description of the drawings]

FIG. 1 is an enlarged plan view showing a gap depth management pattern according to an embodiment of the present invention.

FIG. 2 is a plan view showing an outline of an entire thin film magnetic head element.

FIG. 3 is a cross-sectional view showing a manufacturing process of a coil and a gap depth management pattern.

FIG. 4 is an end view of the embodiment as seen from the polishing surface side.

[Explanation of symbols]

 10 ... Magnetic head element 12 ... Tip part 14 ... Rear end part 16 ... Magnetic pole part 18 ... Coil 20, 22 ... Lead wire 24 ... Magnetic pole 24A ... Upper magnetic pole layer 24B ... Lower magnetic pole layer 24C ... Magnetic pole center 26, 28 ... Marker (Gap depth management pattern) 26C, 28C ... Marker center 30 ... Polishing surface 32 ... Bottom 50, 80 ... Substrate 52 ... Insulating film 56 ... Metal film 82 ... Gap layer 84, 86 ... Insulating layer L ... Gap depth PQ , PA, P1, P2, P3 ... Polishing position W ... Marker interval θ ... Angle

Claims (3)

[Claims] 1. A thin film magnetic head in which a magnetic pole around which a coil is wound is formed on a substrate with a gap layer sandwiched between the magnetic pole and a gap depth management pattern that is non-parallel to the gap depth direction, beside the magnetic pole. A thin-film magnetic head characterized by being formed. 2. The thin film magnetic head according to claim 1, wherein the gap depth management pattern is formed symmetrically with respect to the center of the magnetic pole and along the head shape. 3. The method of manufacturing a thin-film magnetic head according to claim 1, wherein the gap depth management pattern is formed by using a material different from a material around the coil pattern when manufacturing the coil pattern. A method of manufacturing a thin film magnetic head characterized by the above.