JP2004062984A - Disk, head, disk device, and manufacturing method of disk - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disk, a head, and a disk device by which the high speed of a transfer rate is attained and the manufacturing of the disk is made easy, and the manufacturing method of the disk. <P>SOLUTION: In the magnetic disk, a track for tracking consisting of magnetic patterns is formed in a single helical shape or in a concentric circle shape on the lower layer 30 of the recording layer 3a of this magnetic disk and a plurality of recording tracks 33 are formed corresponding to one track 31 for tracking on the upper layer 32 of the recording layer 3a. Thus, the manufacturing of the disk becomes easy as compared with that of a disk on which tracks for tracking of the same number as that of recording tracks are formed and also the high speed of a transfer rate is attained by performing simultaneous reproduction from the plurality of the recording tracks by using a plurality of magnetic sensors. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a disk such as a magnetic disk and a magneto-optical disk, a head, a disk device, and a method of manufacturing the disk. And a method for producing the same.
[0002]
[Prior art]
In recent years, the recording density of a hard magnetic recording device (HDD) has been increasing at an annual rate of 100%, and has reached an experimental level of 100 Gbps, but the track pitch in that case has been reduced to 0.17 μm, and below that. It is becoming difficult to form a magnetic gap having a width of 2 mm or a low-cost tracking track.
[0003]
9A and 9B show an outline of a tracking control mechanism in a conventional magnetic disk, wherein FIG. 9A is a cross-sectional view and FIG. 9B is a top view. As shown in FIG. 9A, the magnetic disk is written on the magnetic disk with a servo writer that generates a magnetic field stronger than the magnetic field of the recording head after the magnetic disk is mounted on the shaft of the rotary motor. The tracking tracks 31a and 31b are formed in the lower layer 30 so as to be shifted by a half pitch. Since the spatial frequency of the tracking track 31 is lower than the spatial frequency of the recording mark, even if the tracking track 31 is written in the lower layer, the magnetic field formed by the tracking track 31 extends sufficiently to the surface and can be detected by the magnetoresistive sensor 12. it can. The direction of magnetization of the tracking track 31 is formed every other track with respect to the recording direction, inverting at different left and right periods, or being shifted from each other.
[0004]
A conventional magnetic head that records and reproduces data on and from such a magnetic disk has a magnetoresistive sensor 12 running on a pair of tracking tracks 31, 31, and a magnetic gap arranged in parallel with the magnetoresistive sensor 12. A magnetic transducer (not shown).
[0005]
At the time of recording / reproducing, the magnetic resistance sensor 12 of the magnetic head is caused to travel between the pair of tracking tracks 31, 31, and the magnetic intensity signal 81 from the pair of tracking tracks 31, 31 is frequency-separated by band-pass filters 82a, 82b. An arithmetic circuit 35 forms a track position error signal 36 from the current fluctuation signals 34a and 34b obtained by the detection. Then, tracking control is performed using the track position error signal 36. At the time of reproduction, a recording signal is reproduced from the recording track 33 by the magnetoresistive sensor 12. At the time of recording, recording is performed by a leakage magnetic field from a magnetic gap (not shown) formed in parallel with the magnetoresistive sensor 12.
[0006]
[Problems to be solved by the invention]
However, according to the conventional magnetic disk, the same number of tracking tracks as the recording tracks is required, and as the width of the recording tracks becomes narrower as the recording density increases, the width of the tracking tracks must be narrowed accordingly. However, it is difficult for production facilities such as photolithography to reduce the width of the tracking track in order to increase the recording density.
Further, since the tracking track is formed by assembling the magnetic disk on the shaft of the rotary motor and then writing by a servo writer, it takes a long time to form the tracking track.
As an alternative to this, a method of forming a tracking pattern in advance on a lower side of a recording medium by a lithography process using an electron beam has been considered. In this case, too, a pattern with a width of several tens of nm is required, which is difficult to manufacture. In addition, after the pattern of the track for tracking is formed, the recording disk is attached to the shaft of the rotary motor. Compared with this, the band of the tracking control needs to be increased by one digit or more, which causes great difficulty.
[0007]
Accordingly, an object of the present invention is to provide a disk, a head, a disk device, and a method of manufacturing a disk, which can achieve a high transfer rate and can easily manufacture the disk.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a disk characterized in that at least one tracking track and a plurality of recording tracks are magnetically formed corresponding to the one tracking track.
According to this configuration, when the tracking tracks are formed in a single spiral or concentric shape, a plurality of recording tracks are formed between the tracking tracks.
[0009]
In order to achieve the above object, the present invention provides a head that levitates and runs on a disk on which a plurality of recording tracks are formed corresponding to one tracking track. A plurality of magnetic sensors for detecting a signal, wherein a pair of adjacent magnetic sensors among the plurality of magnetic sensors travel on one edge side and the other edge side of the one tracking track, respectively, to form a pair of tracks; Provided is a head for detecting a signal.
According to this configuration, when the pair of magnetic sensors outputs a pair of track signals from the tracking track, a track position error signal is generated from the difference between the track signals, and the trunking is performed based on the track position error signal. A plurality of magnetic sensors including the magnetic sensor detect a recording signal from a recording track.
[0010]
In order to achieve the above object, the present invention provides a disk device having a disk on which a plurality of recording tracks are formed corresponding to one tracking track, and a head floating and running on the disk, wherein the head is A plurality of magnetic sensors for detecting a plurality of recording signals by traveling on a plurality of recording tracks, wherein a pair of adjacent magnetic sensors among the plurality of magnetic sensors are on one edge side of the one tracking track and A disk device is provided which travels on the other edge side to detect a pair of track signals.
According to this configuration, a magnetic recording disk device that performs tracking based on a pair of track signals detected by a pair of magnetic sensors and detects a recording signal from a recording track by a plurality of magnetic sensors including the pair of magnetic sensors is configured. You.
[0011]
In order to achieve the above object, the present invention forms a photoresist film on a disk substrate, irradiates the photoresist film with exposure light having a width corresponding to a plurality of recording tracks, and the exposure light is irradiated. Developing the photoresist film to form a mask from the portion of the photoresist film where the exposure light has not been irradiated, forming the grooves for tracking tracks by etching the disk substrate through the mask, Forming a tracking magnetic film in the groove to form the tracking track; and forming a recording magnetic film on which the plurality of recording tracks are formed on the disk substrate on which the tracking track is formed. A method for manufacturing a disk is provided.
According to this configuration, by using the exposure light having a large diameter corresponding to the plurality of recording tracks, the pitch of the tracking tracks is increased, and a plurality of recording tracks are formed between the tracking tracks. Therefore, the number of tracking tracks is reduced as compared with the related art in which the same number of tracking tracks as recording tracks are formed, and the time for forming tracking tracks is reduced.
[0012]
In order to achieve the above object, the present invention forms a recording layer on a disk substrate, forms a magnetic pattern in which a magnetization direction is alternately reversed by applying a modulation magnetic field with a predetermined width to the recording layer, A method for manufacturing a magnetic disk, characterized in that a tracking track having a width smaller than the predetermined width is formed by applying a magnetic field in a certain direction to a part of a pattern.
According to this configuration, after a modulation magnetic field is applied to the recording layer by the magnetic transducer for writing to form a magnetic pattern and then a part of the magnetic pattern is erased by the magnetic transducer for erasing, the magnetic pattern that has not been erased is erased. It becomes a track for tracking.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows a disk drive according to a first embodiment of the present invention. The disk device 1 includes a magnetic disk 3 using a magnetic recording medium mainly composed of CoCr as a recording layer 3a, a rotation motor 4 for rotating the magnetic disk 3, and a floating medium on the recording layer 3a. 3a, a magnetic head 2 for recording / reproducing, a swing arm 5 supporting the magnetic head 2, a voice coil motor 6 for scanning the swing arm 5, a signal processing unit 7 for recording / reproducing, A control unit 8 for controlling the motor 4 and the voice coil motor 6 during reproduction;
[0014]
2A and 2B show the configuration of the magnetic head 2, wherein FIG. 2A is a sectional view, FIG. 2B is a bottom view of a main part, and FIGS. 2C and 2D show a magnetoresistive sensor described later. As shown in FIG. 2A, the magnetic head 2 mainly includes a flying slider 11 that floats and runs on the surface of the magnetic disk 3, a magnetoresistive sensor 12 and a thin film laminated on a rear end surface 11a of the flying slider 11. And a magnetic transducer 13 for recording / reproducing information on / from the recording layer 3a of the magnetic disk 3.
[0015]
The flying slider 11 is, for example, an Altic (Al ₂ O ₃ -TiO ₂ ), And has a floating surface 11c having a concave portion 11b formed on the bottom surface.
[0016]
As shown in FIG. 2B, the magnetoresistive sensor 12 has a plurality of (two in this embodiment) detecting sections 12a and 12b formed in parallel, and the thin-film magnetic transducer 13 is formed in parallel. A plurality of (two in this embodiment) magnetic gaps 13a and 13b are provided so that simultaneous recording and reproduction can be simultaneously performed on a plurality of recording tracks independently. As the magnetoresistive sensor 12, for example, a GMR (Giant Magneto-Resistive) sensor can be used. The width of each of the detection units 12a and 12b and the magnetic gaps 13a and 13b is about 50 nm, and the interval is 20 nm.
[0017]
As shown in FIGS. 2C and 2D, the magnetoresistive sensor 12 is of a type (CPP (Current Perpendicular to Plane GMR) Head) that allows a current to flow perpendicular to the film surface. , Spin valve films 20a and 20b are connected to electrodes 21a, 22a, 21b and 22b, respectively, ₂ Etc., and has a structure sandwiched between two magnetic shield films 24a and 24b. With this structure, a current is independently supplied to each of the spin valve films 20a and 20b, and a change in the resistance is extracted through the signal processing unit 7, thereby detecting a change in the magnetic field from the recording layer 3a of the magnetic disk 3 or the tracking mark 31. be able to. Since the magnetoresistive sensor 12 allows current to flow perpendicularly to the spin valve films 20a and 20b, the widths of the electrodes 21a, 22a, 21b and 22b provided above and below the spin valve films 20a and 20b can be made relatively wide. It has a configuration suitable for individual integration. Further, as the magnetoresistive sensor, not only the CPP-GMR but also a TMR (Tunnel Magneto-Resistive) sensor using a tunnel current flowing through an insulating film may be used.
[0018]
3A and 3B show a recording main part of the magnetic disk 3, wherein FIG. 3A is a top view, and FIG. 3B is a sectional view showing the signal processing unit 7. As shown in FIGS. 3A and 3B, the recording layer 3a of the magnetic disk 3 has a lower layer 30 on which a tracking track 31 for tracking is formed, and recording marks 33a and 33b formed on a recording track 33. Upper layer 32. As the recording layer 3a, a normal CoCr-based magnetic film can be used. The tracking track 31 may be formed by lithography using an electron beam, or may be formed by a servo writer using a magnetic transducer that generates a strong magnetic field with a relatively wide gap width.
[0019]
As shown in FIG. 3B, the signal processing unit 7 calculates the difference between the current variation signals 34a and 34b as track signals by using the arithmetic circuit 35 to generate a track position error signal shown in FIGS. 3B and 3C. 36 is formed. For reproducing the track signal and the recording signal of the recording layer 3a, current fluctuation signals 34a and 34b of the current flowing through the spin valve films 20a and 20b are used. That is, the detection portions 12a and 12b of the spin valve films 20a and 20b are caused to run with the tracking track 31 interposed therebetween, and the current fluctuation signals 34a and 34b are independently processed, whereby the recording marks 33a and 33b of the upper layer 32 are processed. Can reproduce the recorded signal. The tracking track 31 is formed in a single spiral shape, and when the magnetic disk 3 makes one rotation, the detection units 12a and 12b move to the positions of 12a 'and 12b'. The moving pitch p is a value obtained by adding an interval between recording tracks to the width of one recording mark 33a and the other recording mark 33b.
[0020]
The control unit 8 performs tracking control using the track position error signal 38 from the signal processing unit 7. In FIG. 3C, reference numeral 37 denotes a track cross direction.
[0021]
According to this embodiment, the number of tracking tracks 31 can be reduced to the number of the magnetic sensors or magnetic gaps of the magnetic head with respect to the number of recording tracks 33 (the pitch is equal to the number of magnetic sensors or the like). Times the number of times), and the production time can be greatly reduced. In addition, in the conventional method of manufacturing a plurality of recording tracks, one tracking track corresponds to one recording track. Therefore, the number of tracking tracks must be a plurality of spirals by the number of magnetic sensors or the like. And manufacturing precision was required. Alternatively, when a single tracking track is tracked by a plurality of magnetic sensors, a track jump for each rotation is required, which complicates the control mechanism. However, according to the present embodiment, the track for tracking may be formed in a single spiral, and the manufacturing of the track for tracking is simplified, and a plurality of recording tracks are automatically formed on both sides thereof. In spite of the fact that a plurality of recording tracks are formed, it is possible to trace each recording track by a so-called single stroke without a track jump. In addition, a pair of magnetic sensors disposed on the left and right of a single tracking track are run so that the detection units of the magnetic sensors partially overlap the tracking track, and a track position signal is read. Can be arbitrarily set in accordance with the medium structure. The period of the magnetization reversal can also be arbitrarily selected as long as the frequency is sufficiently lower than the period of the recording magnetization. Also in the signal processing, since the position shift signals of the same frequency are detected by the separate magnetic sensors, frequency separation is not required, and the processing circuit can be simplified. Further, an address signal may be written in the tracking track, so that it is not necessary to write the address signal in the recording track portion, and the net recording capacity can be increased.
[0022]
FIG. 4 shows one manufacturing method of the magnetic disk 3 according to the present embodiment. In this manufacturing method, a lithography method using an electron beam was used. That is, as shown in FIG. 4A, first, a positive photoresist film 52 for electron exposure is applied to a glass disk substrate 51, and an electron beam 54 is irradiated while rotating the disk substrate 51. Then, dry etching is performed using the resist pattern 52a left in a single spiral or concentric shape after development as a mask to form grooves 53a and 53b for embedding tracking tracks in the disk substrate 51. The pitch P of the feed of the electron beam 54 is a value obtained by subtracting a half of the width of the tracking track from twice 2T of the recording track width T. For this reason, the diameter of the electron beam 54 can be much larger than the width of the recording track or tracking track, and the ease of fabrication is greatly improved. After the exposure, the portions other than the resist pattern 52a, which is the exposed portion, are developed and removed, and the resist pattern 52a shown in FIG. 4B is used as a mask to perform dry etching using a fluorinated gas and a directional ion beam, Grooves 53a and 53b are formed. As shown in FIG. 4C, magnetic films 55a and 55b mainly composed of CoCr are deposited thereon by sputtering, and the resist pattern 52a is further melted to lift off and remove the excess magnetic film 55a. By further magnetizing, a tracking track 55c is formed. Further thereon, a magnetic film 56 mainly composed of CoCr and a surface protection film 57 mainly composed of DLC (Diamond-Like Carbon) are formed.
[0023]
5A and 5B show another manufacturing method of the magnetic disk 3 according to the present embodiment, wherein FIG. 5A is a sectional view of a main part, and FIG. 5B is a top view. In this manufacturing method, a tracking track is formed using a servo writer magnetic head having two magnetic transducers for writing and erasing. FIG. 5 shows only the magnetic gaps 61 and 62 of the two magnetic transducers. The structure of each of these magnetic transducers is the same as that of a normal one. However, as shown in FIG. 5, the positions of the magnetic gaps 61 and 62 are perpendicular to the track as shown in FIG. Are shifted from each other only by the width of the tracking track 59, that is, in this embodiment, the center is shifted by 50 nm in a direction perpendicular to the track direction. In the track direction, the magnetic transducers are formed apart from each other by the thickness of the magnetic transducer, that is, by several μm. A magnetic head having these two magnetic gaps 61 and 62 scans over the magnetic recording layer 58 of the magnetic disk, and applies a modulation magnetic field to the write magnetic gap 61 and a constant magnetic field to the erase magnetic gap 62. The light is emitted to form a tracking track 59. That is, the magnetic field from the magnetic gap 61 for writing is modulated at a constant modulation speed sufficiently lower than the recording modulation speed, and forms a magnetization 59a that alternates periodically in the track direction. Then, a magnetic field in a certain direction is applied to erase a part of the magnetization 59a formed in the magnetic gap 61 for writing. In this way, a tracking track 59 smaller than the width of each of the magnetic gaps 61 and 62 is formed. These magnetic gaps 61 and 62 are sufficiently wider than the gap width of a recording / reproducing magnetic head (not shown), and thus a tracking track is formed up to the lower layer 30 deep in the magnetic recording layer 58. At the time of recording / reproducing, a recording mark is formed in the upper layer 32 which is relatively shallow, whereby the upper part of the tracking track is partially erased, but the lower layer 30 is preserved and used for forming a tracking control signal.
[0024]
FIG. 6 shows an example of a tracking track. As shown in FIG. 6A, the tracking track 59 is composed of magnetic domains 71b in which the magnetization directions 71a are alternately reversed in the track direction, and the detection sections 12a and 12b of the magnetoresistive sensor of the recording magnetic head are formed thereon. By scanning, a track position error signal is formed as described in FIG. Incidentally, 52b in FIG. 6 indicates the magnetization direction of the track periphery.
[0025]
As shown in FIG. 6B, an address recording mark may be written in the tracking track 59. Accordingly, it is not necessary to form an address mark in a recording track, and the actual recording density can be increased. The tracking track may be wobbled (not shown), and the same effect can be obtained by writing an address signal.
[0026]
Further, as shown in FIG. 6C, the tracking track 59 may be configured by magnetic domains 71b in which the magnetization directions 71a are alternately reversed in a direction perpendicular to the track direction (transverse direction). In this case, since the directions of the magnetic fields entering one detecting section 12a and the other detecting section 12b of the magnetoresistive sensor are always opposite in polarity, a track position error signal can be formed by adding the two. Also, since the magnetic gap of the magnetic head of the servo writer is arranged in parallel with the track, the gap width may be equal to or less than the length of the magnetic domain of the tracking track, so that about 1 μm is sufficient. Can be used, and cost reduction can be achieved.
[0027]
The tracking track according to the above-described embodiment uses a so-called in-plane magnetization film having magnetization in the in-plane direction of the recording layer. However, as shown in FIG. Even when a perpendicular magnetic film or a magneto-optical film such as TbFeCo is used, the tracking track 59 of the present embodiment can be formed. In that case, the magnetization direction 71a of the tracking track is also formed vertically.
[0028]
When a magneto-optical film is used for the recording layer, as shown in FIG. 6E, an in-plane magnetic film may be formed on the lower layer 30 of the magneto-optical film 72, and the tracking track 59 may be formed thereon. . Thus, an in-plane magnetization film having a large leakage magnetic field can be used independently of the recording layer, and a high-quality tracking signal can be formed. Further, since a film having a high Curie temperature can be used, the magnetization of the tracking track 59 is not erased by heat at the time of writing to the magneto-optical film, and stable signal formation can be performed. Similar effects can be obtained when a perpendicular recording medium such as CoPt is used in addition to the magneto-optical film.
[0029]
7A and 7B show main parts of a magnetic head 2 used in a magnetic disk recording device for optically assisted magnetic recording according to a second embodiment of the present invention, wherein FIG. FIG. 4 is a diagram showing a laser light emitting end of FIG. In the magnetic head 2, a semiconductor laser 15, a thin-film magnetic transducer 13, and a magnetoresistive sensor 12 are stacked in this order on a rear end surface 11 a of a flying slider 11. As shown in FIG. 7B, the magnetic gaps 13a, 13d and 13c ', 13c', 13d 'of the thin-film magnetic transducer 13 are provided at the laser beam emitting end so as to block the laser output light 15a. 13b are formed, and they are arranged on both sides of the tracking track 31. With this configuration, the laser beam and the modulation magnetic field can be applied to the same place, and the magnetic gaps 13a and 13b can be arranged close to both sides of the tracking track 31. Further, recording marks can be simultaneously formed on two recording tracks by one laser output light 15a, so that light utilization efficiency can be improved. Further, by applying the laser light in a pulsed manner in synchronization with the modulation magnetic field, unnecessary heating can be prevented, and the light use efficiency can be further increased.
[0030]
FIGS. 8A and 8B show a third embodiment of the present invention, wherein FIG. 8A is a bottom view of a main part of a magnetic head, and FIG. 8B is a sectional view of a magnetic disk. In this magnetic head 2, as shown in FIG. 8A, the magnetoresistive sensor 12 has four detecting portions 12a formed in parallel. ₁ , 12a ₂ , 12b ₁ , 12b ₂ And the thin-film magnetic transducer 13 has four magnetic gaps 13a formed in parallel. ₁ , 13a ₂ , 13b ₁ , 13b ₂ , So that simultaneous recording and reproduction can be simultaneously performed on four recording tracks independently. As shown in FIG. 8B, the magnetic disk 3 to be recorded / reproduced by the magnetic head 2 configured as described above has a recording layer 3a including a lower layer 30 and an upper layer 32 formed on a substrate 3b. A tracking track 31 is formed on the lower layer 30, and four recording tracks 33 are formed on the upper layer 32. According to this configuration, recording and reproduction can be performed on four recording tracks 33 at the same time, so that a higher transfer rate can be achieved.
[0031]
Note that the present invention is not limited to the above embodiments, and it is possible to mount more magnetic gaps and magnetic sensors. Also in that case, the tracking signal can be formed by two of the magnetic sensors. Further, by forming a track cross signal including the remaining magnetic sensors, it is possible to more accurately measure the relative speed and position of the disk with the magnetic head and the magnet during the seek operation.
Further, the width of the tracking track may be larger than the width of the recording track. For example, by making it twice, both the pull-in width and the signal strength become twice.
[0032]
【The invention's effect】
As described in detail above, according to the present invention, the number of tracking tracks is reduced as compared with the related art in which the same number of tracking tracks are formed as the recording tracks, so that the formation time of the tracking tracks is reduced, and Can be easily manufactured. Further, since a plurality of recording tracks can be formed between the tracking tracks, high recording density can be achieved. By simultaneously reproducing data from a plurality of recording tracks using a plurality of magnetic sensors, a high transfer rate can be achieved.
[Brief description of the drawings]
FIG. 1 is a diagram showing a disk device according to a first embodiment of the present invention.
2 (a) is a sectional view, FIG. 2 (b) is a bottom view of an essential part, and FIGS. 2 (c) and 2 (d) are magnetic resistances relating to a magnetic head used in the disk drive according to the first embodiment of the present invention. It is a figure showing a sensor.
3A and 3B relate to a method of forming a track error signal with a magnetic disk used in a disk device according to a first embodiment of the present invention, wherein FIG. 3A is a top view, FIG. 3B is a cross-sectional view, and FIG. FIG. 4 is a diagram illustrating a track position error signal.
FIGS. 4A to 4D are diagrams illustrating a method of manufacturing a magnetic disk used in the disk device according to the embodiment of the present invention.
FIGS. 5A and 5B are diagrams showing another method of manufacturing a magnetic disk used in the disk device according to the embodiment of the present invention.
FIGS. 6A to 6E are diagrams showing tracking tracks of the disk according to the embodiment of the present invention.
FIGS. 7A and 7B show a magnetic head for optically assisted magnetic recording according to a second embodiment of the present invention, in which FIG.
8A is a bottom view of a main part of a magnetic head according to a third embodiment of the present invention, and FIG. 8B is a sectional view of a magnetic disk.
FIGS. 9A and 9B relate to a tracking control mechanism in a conventional magnetic disk, where FIG. 9A is a cross-sectional view and FIG. 9B is a top view.
[Explanation of symbols]
1 Magnetic disk drive
2 Magnetic head
3 Magnetic disk
3a Recording layer
3b substrate
4 rotating motor
5 Swing arm
6 Voice coil motor
7 Signal processing unit
8 Control part
11 Flying slider
11a Rear end face
11b recess
11c Floating surface
12 Magnetoresistive sensor
12a, 12b, 12a ₁ , 12a ₂ , 12b ₁ , 12b ₂ Detection unit
13 Thin-film magnetic transducer
13a, 13b, 13a ₁ , 13a ₂ , 13b ₁ , 13b ₂ Magnetic gap
13c Yoke tip
15 Semiconductor laser
15a Laser output light
20a, 20b Spin valve film
21a, 22a, 21b, 22b Electrodes
23 Insulating film
24a, 24b Magnetic shield film
30 lower layer
31 Tracking Track
32 upper class
33 recording tracks
33a, 33b Recording mark
34a, 34b Current fluctuation signal
35 Arithmetic circuit
36 Track position error signal
51 disk board
52 Positive photoresist film
52a resist pattern
52b Magnetization direction
53a, 53b Groove
54 electron beam
55a, 55b magnetic film
55c tracking track
56 Magnetic film
57 Surface protective film
58 Magnetic Recording Layer
59 Tracking Track
59a Magnetization
61, 62 Magnetic gap
71a Magnetization direction
71b magnetic domain
72 Magneto-optical film
81 Magnetic strength signal
82a, 82b band pass filter

Claims (22)

A disk characterized in that at least one tracking track and a plurality of recording tracks are magnetically formed corresponding to the one tracking track. The at least one tracking track is formed as a single spiral or concentric circle at a pitch of N × P, where N is the number of the plurality of recording tracks and P is the pitch. Item 10. The disk according to Item 1. 2. The disk according to claim 1, wherein the tracking track is formed by in-plane magnetization whose magnetization direction is alternately reversed in the track direction. 2. The disk according to claim 1, wherein the tracking track is formed of in-plane magnetic domains whose magnetization directions are alternately reversed in a direction perpendicular to the track direction. 2. The disk according to claim 1, wherein the tracking track is formed of a vertical magnetic domain whose magnetization direction is alternately reversed in a direction perpendicular to the disk surface. 2. The disk according to claim 1, wherein the tracking track is formed of magnetic domains whose magnetization directions are alternately reversed, and an address signal is written by changing the length of the magnetic domains in the track direction. 2. The disk according to claim 1, wherein an address signal is written on the tracking track by a periodic wobble in a direction perpendicular to the track direction. The tracking track is formed below the recording layer,
The disk according to claim 1, wherein the plurality of recording tracks are formed in an upper layer portion of the recording layer. The tracking track is formed in an upper layer portion of a recording layer,
2. The disk according to claim 1, wherein the plurality of recording tracks are formed below the recording layer. 10. The disk according to claim 8, wherein the recording layer is formed from an in-plane magnetic recording film such as CoCr, a perpendicular magnetic recording film such as CoPt, or a magneto-optical recording film such as TeFeCo. In a head flying and floating on a disk on which a plurality of recording tracks are formed corresponding to one tracking track,
Comprising a plurality of magnetic sensors running on the plurality of recording tracks to detect a plurality of recording signals,
A head, wherein a pair of adjacent magnetic sensors among the plurality of magnetic sensors travel on one edge side and the other edge side of the one tracking track, respectively, to detect a pair of track signals. In a head flying and floating on a disk on which a plurality of recording tracks are formed corresponding to one tracking track,
A plurality of magnetic transducers that run on the plurality of recording tracks and record a plurality of recording signals on the plurality of recording tracks;
A plurality of magnetic sensors that detect the plurality of recording signals by traveling on the plurality of recording tracks,
A head, wherein a pair of adjacent magnetic sensors among the plurality of magnetic sensors travel on one edge side and the other edge side of the one tracking track, respectively, to detect a pair of track signals. In a head flying and floating on a disk on which a plurality of recording tracks are formed corresponding to one tracking track,
A laser light emitting end that travels on the plurality of recording tracks and irradiates the plurality of recording tracks with laser light;
A plurality of magnetic transducers that run on the plurality of recording tracks and record a plurality of recording signals on the plurality of recording tracks heated by the irradiation of the laser light,
A plurality of magnetic sensors that detect the plurality of recording signals by traveling on the plurality of recording tracks,
A head, wherein a pair of adjacent magnetic sensors among the plurality of magnetic sensors travel on one edge side and the other edge side of the one tracking track, respectively, to detect a pair of track signals. 14. The head according to claim 13, wherein a plurality of magnetic gaps of the plurality of magnetic transducers are formed at a single laser emitting end. 14. The head according to claim 11, wherein the magnetic sensor comprises a giant magnetoresistive sensor. 14. The head according to claim 11, wherein the magnetic sensor comprises a tunnel type magnetoresistive sensor. In a disk device having a disk on which a plurality of recording tracks are formed corresponding to one tracking track, and a head floating and running on the disk,
The head is
Comprising a plurality of magnetic sensors running on the plurality of recording tracks to detect a plurality of recording signals,
A disk device, wherein a pair of adjacent magnetic sensors among the plurality of magnetic sensors travel on one edge side and the other edge side of the one tracking track, respectively, to detect a pair of track signals. . In a disk device having a disk on which a plurality of recording tracks are formed corresponding to one tracking track, and a head floating and running on the disk,
The head is
A plurality of magnetic transducers that run on the plurality of recording tracks and record a plurality of recording signals on the plurality of recording tracks;
A plurality of magnetic sensors that detect the plurality of recording signals by traveling on the plurality of recording tracks,
A disk device, wherein a pair of adjacent magnetic sensors among the plurality of magnetic sensors travel on one edge side and the other edge side of the one tracking track, respectively, to detect a pair of track signals. . In a disk device having a disk on which a plurality of recording tracks are formed corresponding to one tracking track, and a head floating and running on the disk,
The head is
A laser light emitting end that travels on the plurality of recording tracks and irradiates the plurality of recording tracks with laser light;
A plurality of magnetic transducers that run on the plurality of recording tracks and record a plurality of recording signals on the plurality of recording tracks heated by the irradiation of the laser light,
A plurality of magnetic sensors that detect the plurality of recording signals by traveling on the plurality of recording tracks,
A disk device, wherein a pair of adjacent magnetic sensors among the plurality of magnetic sensors travel on one edge side and the other edge side of the one tracking track, respectively, to detect a pair of track signals. . 20. The disk drive according to claim 17, wherein the head is tracked in an arc shape so as to intersect in a track direction. Forming a photoresist film on the disk substrate,
Irradiating the photoresist film with exposure light having a width corresponding to a plurality of recording tracks,
The exposure light is developed to form a mask from the part of the photoresist film that is not irradiated by developing the photoresist film,
Etching the disk substrate through the mask to form grooves for tracking tracks,
Embedding a tracking magnetic film in the groove to form the tracking track,
A method for manufacturing a disk, comprising: forming a recording magnetic film on which the plurality of recording tracks are formed on the disk substrate on which the tracking tracks are formed. Forming a recording layer on the disk substrate,
Applying a modulation magnetic field with a predetermined width to the recording layer to form a magnetic pattern in which the magnetization direction is alternately reversed,
A method for manufacturing a magnetic disk, comprising: applying a magnetic field in a certain direction to a part of the magnetic pattern to form a tracking track having a width smaller than the predetermined width.

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