JP2005243195A - Magnetic head device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To give compatibility to different formats. <P>SOLUTION: The magnetic head of each channel is provided with a 1st thin film magnetic head 3 having a 1st track width specified by a pair of magnetic poles 6, 8 formed on the upper surface of a substrate 2, and a 2nd thin film magnetic head 5 having a 2nd track width specified by a pair of magnetic poles 8, 10 positioned on the upper surface of the 1st thin film magnetic head 3. The 1st track width and the 2nd track width are different from each other. Recording and reproduction are performed in two kinds of formats with different track pitches by optionally changing over from one to the other for the use. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a magnetic head device suitable as a multi-channel head used in, for example, a helical scan system.

  Conventionally, a magnetic tape is wound obliquely around the outer peripheral surface of a rotating drum having a magnetic head attached to the outer peripheral surface, and the magnetic head that moves as the rotating drum rotates is slid obliquely with respect to the magnetic tape. A recording / reproducing method called a helical scan method that records or reproduces a signal on a magnetic tape has been proposed. In this helical scan system, high-density recording is achieved by alternately forming tracks having azimuths different from each other in the tape running direction, and the magnetic head slides at high speed on the running magnetic tape. By performing recording and reproduction, the data transfer rate is improved.

As a magnetic head used in this helical scan system, a thin film type magnetic head is widely used because it has a merit that the track height between different channels can be collectively produced in a wafer with high accuracy. For example, in Patent Document 1, magnetism is performed along the direction in which the substrate material, the nonmagnetic layer in which the thin film magnetic head is provided, and the auxiliary member are aligned with each other or inclined at a predetermined angle with respect to the auxiliary member. A thin film magnetic head that forms a sliding surface that slides on a tape has been proposed. According to the technique described in Patent Document 1, the nonmagnetic layer can be made thin and the area of the nonmagnetic layer on the sliding surface can be reduced, so that the slidability with the magnetic tape can be improved.
JP 2000-249912 A

  By the way, various formats have been established as magnetic recording / reproducing systems so far. For example, even when only a DDS (Digital Date Storage) adopting a helical scan system is taken as an example, a plurality of formats such as DDS3, DDS4, DDS5, etc. Format exists. Therefore, it is important to maintain backward compatibility in a magnetic recording / reproducing apparatus equipped with a thin film type magnetic head. However, since the track pitch required for each format differs, it has a single track width. It is difficult for the manufactured thin film magnetic head to cope with various formats.

  Therefore, the present invention has been proposed in view of such a conventional situation, and an object of the present invention is to provide a multichannel magnetic head device having compatibility with different formats.

  In order to solve the above-described problem, a magnetic head device according to the present invention is a multi-channel magnetic head device including a plurality of channels of magnetic heads, and the magnetic head of each channel has a first track width. It has a first write magnetic pole and a second write magnetic pole having a second track width different from the first track width.

  Since the magnetic head device having the above configuration has two types of write magnetic poles having different track widths, recording / reproduction can be performed in two types of formats having different track pitches by arbitrarily switching the magnetic poles to be used. Realized.

  According to the present invention, since there are two types of write magnetic poles having different track widths, it is possible to provide a multi-channel type magnetic head device that can support two formats requiring different track pitches.

  Hereinafter, a multi-channel magnetic head device to which the present invention is applied will be described in detail with reference to the drawings.

FIG. 1 is an example of a magnetic head constituting each channel in a multichannel magnetic head device to which the present invention is applied. In this embodiment, the writing magnetic pole is formed as a thin film type magnetic head, but the thin film type magnetic head is formed in accordance with a conventional method by a thin film forming technique. In FIG. 1A, a magnetic head 1 includes a first thin film magnetic head 3 and a nonmagnetic layer made of, for example, Al ₂ O ₃ on a substrate 2 made of, for example, nonmagnetic Al ₂ O ₃ —TiC. 4 and the second thin film magnetic head 5 in this order. As shown in FIG. 1B, the first thin film magnetic head 3 and the second thin film magnetic head 5 have different track widths, and the track width of the first thin film magnetic head 3 is the second thin film magnetic head. It is wider than the track width of the head 5.

  The magnetic head 1 will be described in more detail. The first thin film magnetic head 3 has a structure in which a lower magnetic pole 6, an interlayer insulating film 7, and an upper magnetic pole 8 are sequentially laminated on the upper surface of the substrate 2. The first thin film magnetic head 3 has a coil 9 formed in a thin film shape in the interlayer insulating film 7. The lower magnetic pole 6 and the upper magnetic pole 8, which are write magnetic poles, are in magnetic contact near the center of the wound coil 9 and have a magnetic gap G1 having a predetermined interval on the sliding surface 1a side with the magnetic tape. Formed to compose. The first thin-film magnetic head 3 is formed on the sliding surface 1a of the thin-film magnetic head 1 so as to face the lower magnetic pole 6 and the upper magnetic pole 8 that define the track width. On the upper surface of the first thin film magnetic head 3, a nonmagnetic layer 4 is formed over substantially the entire surface.

  The second thin film magnetic head 5 having a narrower track width than the first thin film magnetic head 3 is stacked on the first thin film magnetic head 3 via the nonmagnetic layer 4. The second thin film magnetic head 5 has a structure in which a lower magnetic pole 10, an interlayer insulating film 11, and an upper magnetic pole 12 are sequentially stacked on the upper surface of the nonmagnetic layer 4. The structure of the second thin film magnetic head 5 is basically the same as that of the first thin film magnetic head 3 and has a coil 13 formed in a thin film shape in the interlayer insulating film 11. The lower magnetic pole 10 and the upper magnetic pole 12 are formed so as to be in contact with each other in the vicinity of the center of the wound coil 13 and to form a magnetic gap G2 having a predetermined interval on the sliding surface 1a side with the magnetic tape. The second thin film magnetic head 5 is formed on the sliding surface 1a of the thin film magnetic head 1 so as to face the lower magnetic pole 10 and the upper magnetic pole 12 that define the track width. On the upper surface of the second thin film magnetic head 5, a protective layer 14 is formed over substantially the entire surface.

In the magnetic head 1 described above, the first thin film magnetic head 3 and the second thin film magnetic head 5 are arranged so that the gap end positions of one of the magnetic gap G1 and the magnetic gap G2 substantially coincide with each other. A case where data is recorded on the magnetic tape by the helical scan method using the magnetic head 1 to which the present invention is applied will be described with reference to FIG.

  In FIG. 2, a case where a pair of magnetic heads 1a and 1b to which the present invention is applied is arranged at a counter electrode position on the outer peripheral surface of a rotating drum and recording is performed on a magnetic tape will be described. The azimuth angles of the magnetic heads 1a and 1b are opposite to each other. As shown in FIG. 2A, for example, when recording is performed in a first format employing a track pitch (channel step) TpA, first thin film magnetic heads 3a and 3b having a track width W1 are used. Tracks having opposite azimuth angle polarities are alternately formed. By alternately and sequentially forming tracks having opposite azimuth angle polarities, crosstalk components due to adjacent tracks are reduced. At this time, recording is performed such that one edge in the width direction of the track recorded by one first thin film magnetic head 3a is overwritten by the other first thin film magnetic head 3b. Thereby, a track pattern having a track pitch TpA is obtained.

  As shown in FIG. 2B, for example, when recording is performed in the second format employing the narrow track pitch TpB, the first thin film magnetic head 3 is switched to the second thin film magnetic head 5. Make a record. As shown in FIG. 2 (b), the second thin film magnetic heads 5a and 5b having a narrow track width W2 are used to alternately and alternately form tracks having opposite azimuth angle polarities. Recording is performed such that one edge in the width direction of the track recorded by the second thin film magnetic head 5a is overwritten by the other second thin film magnetic head 5b. Thereby, a track pattern having a track pitch TpB is obtained.

  As described above, since the magnetic head 1 includes two types of write magnetic poles (thin film magnetic heads) having different track widths, the magnetic head 1 is compatible with different formats, for example, a magnetic field that maintains backward compatibility such as DDS. It can be used as a multi-channel magnetic head mounted on a recording / reproducing apparatus, and can contribute to further improvement in transfer rate.

  Further, according to the magnetic head 1, since each thin film magnetic head 3 and 5 is manufactured by a thin film forming technique, the track width and the track pitch (channel step) are set in units of submicrometers as compared with the manufacturing process by conventional machining. Can be aligned with high accuracy. Therefore, the track width and the track pitch can be adjusted easily and with high accuracy.

  By the way, in the magnetic head 1 in FIG. 1, depending on the format used, the first thin film magnetic head 3 and the second thin film magnetic head 5 can share the magnetic poles on one side adjacent to each other. The magnetic head having such a configuration will be described below with reference to FIG.

The magnetic head 31 shown in FIG. 3 is formed according to a conventional method by a thin film forming technique, similarly to the magnetic head 1 shown in FIG. In FIG. 3A, a magnetic head 31 includes a first thin film magnetic head 33 and a second thin film magnetic head 34 on a substrate 32 made of Al ₂ O ₃ —TiC, Al ₂ O ₃ or the like. Have in order. As shown in FIG. 3B, the first thin film magnetic head 31 and the second thin film magnetic head 34 have different track widths, and the track width of the first thin film magnetic head 31 is the second thin film magnetic head. It is wider than the track width of the head 34.

  As shown in FIG. 3A, the magnetic head 31 has no nonmagnetic layer between the first thin film magnetic head 33 and the second thin film magnetic head 34. It has a common magnetic pole 35 that also functions as the upper magnetic pole and the lower magnetic pole in the second thin film magnetic head 34.

  The magnetic head 31 will be described in more detail. The first thin film magnetic head 33 has a structure in which a lower magnetic pole 36, an interlayer insulating film 37, and a common magnetic pole 35 are sequentially stacked on the upper surface of a substrate 32. . The first thin film magnetic head 33 includes a coil 38 formed in a thin film shape in an interlayer insulating film 37. The lower magnetic pole 36 and the common magnetic pole 35 are formed in contact with each other in the vicinity of the center of the wound coil 38 and to form a magnetic gap G31 having a predetermined interval on the sliding surface 31s side with the magnetic tape. . The first thin film magnetic head 33 is formed on the sliding surface 31 a of the thin film type magnetic head 31 so as to face the lower magnetic pole 36 and the common magnetic pole 35 that define the track width.

  The second thin film magnetic head 34 having a track width narrower than the track width of the first thin film magnetic head 33 has a structure in which a common magnetic pole 35, an interlayer insulating film 39, and an upper magnetic pole 40 are sequentially stacked. It is said that. The second thin film magnetic head 34 includes a coil 41 formed in a thin film shape in an interlayer insulating film 39. The common magnetic pole 35 and the upper magnetic pole 40 are formed so as to be in contact with each other in the vicinity of the center of the wound coil 41 and to form a magnetic gap G32 having a predetermined interval on the sliding surface 31s side with the magnetic tape. . The second thin film magnetic head 34 is formed on the sliding surface 31 s of the magnetic head 31 so as to face the common magnetic pole 35 and the upper magnetic pole 40 that define the track width. On the upper surface of the second thin film magnetic head 34, a protective layer 42 is formed over substantially the entire surface.

  Next, the case where data is recorded on the magnetic tape by the helical scan method using the magnetic head 31 will be described with reference to FIG.

  In FIG. 4, as in FIG. 2, as a recording magnetic head, a pair of magnetic heads 31a and 31b to which the present invention is applied are arranged at the counter electrode position on the outer peripheral surface of the rotating drum and recording is performed on the magnetic tape. explain. The azimuth angles of the magnetic heads 31a and 31b are opposite to each other. As shown in FIG. 4A, for example, when recording in the third format employing a wide track pitch TpC, the first thin film magnetic heads 33a and 33b having a wide track width W31 are used. Tracks having opposite azimuth angle polarities are alternately formed. By alternately and sequentially forming tracks having opposite azimuth angle polarities, crosstalk components due to adjacent tracks are reduced. At this time, recording is performed such that one edge in the width direction of the track recorded by one first thin film magnetic head 33a is overwritten by the other first thin film magnetic head 33b. Thereby, a track pattern having a track pitch TpC is obtained.

  As shown in FIG. 4B, for example, when recording is performed in a fourth format employing a narrow track pitch TpD, the first thin film magnetic head 33 is switched to the second thin film magnetic head 34. Make a record. As shown in FIG. 4B, the second thin film magnetic heads 34a and 34b having a narrow track width W32 are used to alternately and sequentially form tracks having opposite azimuth angle polarities. Recording is performed such that one edge in the width direction of the track recorded by the second thin film magnetic head 34a is overwritten by the other second thin film magnetic head 34b. Thereby, a track pattern having a track pitch TpD is obtained.

  As described above, since the magnetic head 31 includes two types of magnetic poles for writing (thin film magnetic head), it can cope with track pitches of different formats, for example, magnetic recording / reproducing that maintains backward compatibility such as DDS. It can be used as a multi-channel magnetic head mounted on the apparatus.

  Further, when the upper magnetic pole of the first thin film magnetic head 33 and the lower magnetic pole of the second thin film magnetic head 34 are made of the same member, as shown in FIG. Since a fringe magnetic field as shown by a dotted line in the figure is generated between the end of the upper magnetic pole 40 of the second thin-film magnetic head 34 at the midway position, there is a concern about an adverse effect on recording characteristics. When recording is performed so that a part of the track pattern in the track width direction is overwritten by the helical scan method with the magnetic head 31 shown, recording can be performed with good recording characteristics without being affected by the fringe magnetic field. Taking the track pattern of the magnetic head 31a in FIG. 4B as an example, the region affected by the fringe magnetic field in the track pattern by the second thin film magnetic head 34a of the magnetic head 31a is the width direction of the track pattern. This is because the overwriting is performed by the end of the second thin film magnetic head 34b that follows the edge of the second thin film magnetic head 34b that does not disturb the edge. Therefore, the magnetic head 31 can cope with different formats without deteriorating the recording characteristics due to the common use of the upper magnetic pole of the first thin film magnetic head 33 and the lower magnetic pole of the second thin film magnetic head 34. is there.

  As described above, since the magnetic head 31 includes two types of magnetic heads having different track widths, the magnetic head 31 can support different formats, and is mounted on a magnetic recording / reproducing apparatus that maintains backward compatibility, such as DDS. It can be used as a multi-channel magnetic head and contributes to further improvement in transfer rate.

  Further, according to the magnetic head 31, since the thin film magnetic heads 33 and 34 are manufactured by the thin film formation technique, the track width and the track pitch (channel step) are aligned with high accuracy in units of submicrometers in the manufacturing process. be able to. Therefore, the track width and the track pitch can be adjusted easily and with high accuracy.

(A) is a principal part schematic sectional drawing which shows an example of the magnetic head to which this invention is applied, (b) is a figure which shows typically the magnetic head seen from the magnetic tape sliding direction. (A) is a figure which shows typically the track pattern formed with the 1st thin film magnetic head in the magnetic head of FIG. 1, (b) is formed with the 2nd thin film magnetic head in the magnetic head of FIG. FIG. 3 is a diagram schematically showing a track pattern. (A) is a principal part schematic sectional drawing which shows the modification of the magnetic head to which this invention is applied, (b) is a figure which shows typically the magnetic head seen from the magnetic tape sliding direction. (A) is a figure which shows typically the track pattern formed with the 1st thin film magnetic head in the magnetic head of FIG. 3, (b) is formed with the 2nd thin film magnetic head in the magnetic head of FIG. FIG. 3 is a diagram schematically showing a track pattern. FIG. 4 is a diagram schematically showing a state in which a fringe magnetic field is generated in the magnetic head shown in FIG. 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Magnetic head, 2 Substrate, 3 1st thin film magnetic head, 4 Nonmagnetic layer, 5 2nd thin film magnetic head, 6 Lower magnetic pole, 7 Interlayer insulation film, 8 Upper magnetic pole, 9 Coil, 10 Lower magnetic pole, 11 Interlayer Insulating film, 12 Upper magnetic pole, 13 Coil, 14 Protective layer, 31 Magnetic head, 32 Substrate, 33 First thin film magnetic head, 34 Second thin film magnetic head, 35 Common magnetic pole, 36 Lower magnetic pole, 37 Interlayer insulating film, 38 coils, 39 interlayer insulation film, 40 upper magnetic pole, 41 coils, 42 protective layer

Claims (5)

A multi-channel magnetic head device having a multi-channel magnetic head,
The magnetic head of each channel has a first write magnetic pole having a first track width and a second write magnetic pole having a second track width different from the first track width. Magnetic head device.   2. The magnetic head according to claim 1, wherein in the magnetic head of each channel, the first write magnetic pole and the second write magnetic pole are arranged so that one gap end position is substantially coincident. apparatus.   3. A magnetic head device according to claim 1, wherein one of the first magnetic pole for writing and the second magnetic pole for writing has a common magnetic pole on one side.   4. The magnetic head device according to claim 1, wherein the first write magnetic pole and the second write magnetic pole are each a magnetic pole of a thin film magnetic head. 5. The magnetic head device according to claim 4, wherein the magnetic head of each channel is formed by stacking thin film magnetic heads.

Images