JP4008139B2 - Method and apparatus for aligning magnetic head and optical head - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an alignment method and an alignment apparatus for a magnetic head and an optical head provided in a memory device such as a magnetic recording apparatus in which optical recording technology and magnetic recording technology are integrated.
[0002]
[Prior art]
  In recent years, the recording density of an optical memory represented by a DVD (Digital Versatile Disk) or magneto-optical recording and a magnetic memory represented by a hard disk (hereinafter abbreviated as HDD) has been remarkably improved. in²At the research level, 10 Gbit / in² The above recording capacity (in the case of HDD) has been reported.
[0003]
  On the other hand, with the aim of further improving the recording density, a new high-density memory device that combines optical memory technology and magnetic memory technology has been proposed. For example, in Japanese Patent Publication No. 2617025 and JP-A-6-500194, a ferrimagnetic material having a compensation point at room temperature is used as a recording layer of a magnetic recording medium in magnetic recording, and a light beam is used during recording and reproduction. A technique for irradiating and heating is disclosed.
[0004]
  According to the above technique, at the time of recording, a track is recorded with a narrow track pitch equivalent to the light beam diameter (sub-μm to 1 μm) using a magnetic head having a width of several μm to several tens of μm as in the conventional magnetic recording. In playback, tracks recorded with a track pitch narrower than the magnetic head width can be played back without crosstalk. Therefore, since the track density can be improved to the same level as the optical memory while maintaining the same linear density as the conventional magnetic recording, the surface density can be increased several times that of the conventional magnetic recording. It has been.
[0005]
  In order to realize a high-density memory that combines not only this technology but also optical recording technology and magnetic recording technology, there is a technology that irradiates the same region with a light beam by an optical head and applies a magnetic field by the magnetic head. It is essential. Therefore, there has been a need for a method and apparatus for performing alignment (alignment) between a magnetic head and an optical head in a simple manner and with a precision of sub-μm to several μm level.
[0006]
  As a conventional alignment method between an optical head and a magnetic head, for example, there is a method disclosed in JP-A-8-7379. This conventional method will be described with reference to FIG.
[0007]
  In this method, a disk 34 having a translucent film 25 and a protective film 26 formed on a transparent substrate 24 is used as an adjustment disk, the disk 34 is mounted on a turntable 33, and a slider 27 and a magnetic core 28 are placed above the disk 34. On the other hand, an optical head (not shown) including a photodetector is disposed below the disk 34.
[0008]
  Next, after performing a focus control to irradiate a light beam from the optical head toward the magnetic head 35 and focus the light beam on the semi-transparent film 25 using the reflected light 30 from the semi-transparent film 25, the magnetic head 35. , The intensity of the reflected light 31 reflected by the magnetic head 35 and passing through the disk 34 is measured by the photodetector of the optical head.
[0009]
  Then, by utilizing the fact that the reflectance is different between the slider 27 of the magnetic head 35 and the magnetic core 28, the output of the photodetector representing the intensity of the reflected light 31 is detected, and the output depends on the magnetic core 28. The positions of the optical head and the magnetic head 35 are adjusted so that the output is obtained.
[0010]
[Problems to be solved by the invention]
  However, according to the study of the present inventor, it has been found that the above-described conventional method disclosed in JP-A-8-7379 has the following problems.
[0011]
  That is, most of the incident light 29 emitted from the optical head is transmitted through the semitransparent film 25, but a part thereof is reflected by the semitransparent film 25. Further, part of the reflected light reflected by the magnetic head 35 is reflected by the semitransparent film 25 and returns to the magnetic head 35 as reflected light 32, and is reflected between the lower surface of the magnetic head 35 and the semitransparent film 25. It decays repeatedly.
[0012]
  For example, when the transmittance of the semitransparent film 25 is 60%, the reflectance of the semitransparent film 25 is 20%, and the attenuation factor due to absorption of the semitransparent film 25 is 20%, the light that reaches the surface of the magnetic head 35 The intensity is reduced to 60% of the intensity of the incident light 29. Further, the light intensity returning from the magnetic head 35 to the optical head is further attenuated by absorption of the translucent film 25 and the like.
[0013]
  As described above, in the conventional method, since the disk 34 on which the semitransparent film 25 is formed is used for focus control, the reflected light from the surface of the magnetic head 35 is attenuated.
[0014]
  Therefore, the change in the intensity of the reflected light from the surface of the magnetic head 35 obtained by the difference in reflectance between the slider 27 and the magnetic core 28 becomes small. If the change in the intensity of the reflected light is small, it becomes difficult to detect the position of the gap (for example, the gap length is 0.2 to 0.35 μm) of the magnetic head 35 narrower than the light beam diameter (about 1 μm). . As a result, the conventional method has a problem that the precise alignment at the sub-μm level, which is required in a high-density memory, cannot be achieved.
[0015]
  Moreover, various problems arise when the intensity of the emitted light of the alignment light beam is increased. For example, in a magnetic head for high-density memory disclosed in Japanese Patent Publication No. 2617025 and Japanese Patent Publication No. Hei 6-500194, a magnetic core composed of an MR (magnetoresistive) element or a GMR (giant magnetoresistive) element is used. However, when the magnetic head is irradiated with a strong light beam at the time of alignment, a new problem that the characteristics of these MR elements and GMR elements deteriorate is caused.
[0016]
  Further, as pointed out in Japanese Patent Laid-Open No. 8-7379, focus control is performed so that the light beam is focused on the surface of the magnetic head 35 without using the adjusting disk 34 on which the semitransparent film 25 is formed. In this case, the reflected light is not returned by the magnetic gap and the focus is lost, so that the reflected light from the magnetic head cannot be detected stably.
[0017]
  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide an alignment method and alignment apparatus between a magnetic head and an optical head that can stably perform accurate alignment. There is.
[0018]
[Means for Solving the Problems]
  the aboveThe present invention pays attention to the reflected light intensity difference between the magnetic core and the slider obtained by irradiating the magnetic head with the light beam so that the in-focus position of the light beam is substantially on the magnetic head surface. As a result of studying the identification of the position of the magnetic head by measuring the intensity of reflected light with the optical head itself used as a heat source in thermomagnetic recording.
[0019]
  The present inventionPertaining toIn order to solve the above-described problem, the magnetic head and the optical head are aligned with each other such that a magnetic head for generating a magnetic field and an optical head for irradiating a light beam through a movable objective lens face each other. The optical head is provided with a light detection unit for measuring the intensity of the reflected light, and the focusing position of the light beam is close to the surface of the magnetic head. While the objective lens was reciprocated so as to reciprocate in the direction perpendicular to the surface, the optical head irradiated the light beam to measure the intensity of the reflected light from the magnetic head. The positional relationship between the magnetic head and the optical head is adjusted based on the intensity of the reflected light.
[0020]
  According to the above method, the magnetic head is irradiated with the light beam so that the focus position of the light beam reciprocates near the magnetic head surface while the objective lens is reciprocated. As a result, even in the magnetic gap of the magnetic head, and even when the flying height of the magnetic head changes due to a difference in the linear velocity of the recording medium, surface vibration, disturbance, etc., the light beam is magnetized within the moving range of the objective lens. Focus on the head surface.
[0021]
  The intensity of the reflected light shows a peak when focused on the surface of the magnetic head. If the value of this peak is read, the intensity of the reflected light when focused on the surface of the magnetic head can be reliably measured. The intensity of the reflected light when focused on the surface of the magnetic head accurately reflects the reflectivity of the surface of the magnetic head. Therefore, based on the intensity of the reflected light when focused on the surface of the magnetic head, If the positional relationship with the optical head is adjusted, accurate positioning can be stably performed.
[0022]
  In the conventional method described in Japanese Patent Laid-Open No. 8-7379, in order to measure the intensity of reflected light when focused on the surface of the magnetic head, it is necessary to perform focus control and for focusing. It is necessary to interpose an adjusting disk on which the semitransparent film is formed between the magnetic head and the optical head.
[0023]
  On the other hand, according to the above method, it is not necessary to perform focus control, and it is not necessary to interpose an adjustment disk on which a semitransparent film for focusing is formed between the magnetic head and the optical head. Therefore, the reflected light of the magnetic head when focused on the surface of the magnetic head can reach the optical head without being attenuated. For this reason, compared with the conventional method, the intensity of the reflected light when focused on the surface of the magnetic head can be measured with a wider dynamic range, so that more accurate alignment can be performed.
[0024]
  The present inventionPertaining toIn order to solve the above problems, the magnetic head and the optical head are aligned.the aboveIn the alignment method of the magnetic head and the optical head, the intensity of the reflected light is measured by rotating a disk transparent to the light beam between the magnetic head and the optical head, and rotating the magnetic head. It is characterized by being carried out in a state where it is levitated away from the disc.
[0025]
  According to the above method, by rotating the disk and floating the magnetic head away from the disk, not only alignment can be performed under the same conditions as the actual device, but also the disk and magnetic head slide during alignment. You can avoid fitting. For this reason, it is possible to prevent the magnetic head from being damaged during alignment, particularly when an MR head or GMR head that is easily damaged by static electricity is used as the magnetic head.
[0026]
  Further, according to the above method, since the disk is transparent to the light beam, the light beam reaches the magnetic head without being attenuated. For this reason, the change in reflected light intensity can be measured without impairing the dynamic range, and the alignment between the magnetic head and the optical head is facilitated.
[0027]
  The present inventionPertaining toIn order to solve the above problems, the magnetic head and optical head alignment apparatus irradiates and reflects a light beam on a magnetic head through a magnetic head for applying a magnetic field to a recording medium and a movable objective lens. An alignment device that performs alignment by arranging optical heads for measuring the intensity of light so as to face each other, and the focusing position of the light beam is perpendicular to the magnetic head surface near the magnetic head surface. Driving means for reciprocating the objective lens so as to reciprocate in the direction, moving means for moving at least one of the magnetic head and the optical head so that the positional relationship between the magnetic head and the optical head changes, and the optical head and driving And a control means for controlling the moving means based on a change in the intensity of the reflected light measured by the optical head. It is characterized in.
[0028]
  According to the above configuration,the aboveA magnetic head and optical head alignment apparatus capable of automatically executing the method can be provided. Therefore, it is possible to provide a magnetic head and optical head alignment device capable of stably and automatically executing accurate alignment.
[0029]
  By the above-described operation of the present invention, a magnetic head and optical head alignment method and alignment apparatus capable of detecting a gap length narrower than that of a light beam in a simple and precise manner at a sub-μm to μm level are provided. Development of high-density memory devices that integrate technology and magnetic technology.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
  [Embodiment 1]
  An embodiment of a method of aligning a magnetic head and an optical head and an alignment apparatus according to the present invention will be described with reference to FIGS. In this embodiment, an alignment method in which an adjustment disk is arranged between the magnetic head and the optical head will be described. However, the magnetic head is attached to the disk using a jig without arranging the adjustment disk. If it is arranged parallel to the surface, alignment can be performed in the same manner as when the adjustment disk is arranged.
[0031]
  In the alignment apparatus according to the present embodiment, as shown in FIG. 1, a light beam is applied to a magnetic disk through a magnetic head 2 for applying a magnetic field to a magnetic disk (recording medium) (not shown) and a movable objective lens 4. Are arranged so as to face each other. The magnetic disk is mounted between a magnetic head 2 and an optical pickup 3 at the time of recording / reproducing, and is mounted on a spindle 8 that is rotationally driven by a driving device (not shown).
[0032]
  In the alignment method of the magnetic head 2 and the optical pickup 3 according to the present embodiment, an adjustment disk 1 is arranged between the magnetic head 2 and the optical pickup 3 instead of the magnetic disk and is mounted on the spindle 8. is doing.
[0033]
  The magnetic head 2 writes a magnetic signal to the magnetic disk based on the information signal sent from the magnetic signal Read / Write driver 10 during recording. Further, the magnetic head 2 reads (measures) a magnetic signal on the magnetic disk during reproduction, and outputs a reproduction magnetic signal from the magnetic signal Read / Write driver 10. In the present embodiment, a magnetic head capable of only writing magnetic signals may be used instead of the magnetic head 2 capable of writing and reading magnetic signals.
[0034]
  The optical pickup 3 irradiates the magnetic disk with a light beam so that the focused position of the light beam coincides with the recording layer of the magnetic disk in order to raise the temperature of the recording layer of the magnetic disk during recording and reproduction. is there. Here, an optical pickup 3 having a light beam wavelength of 780 nm, a light beam diameter of 1.27 μm, and a focal depth of about 1 μm was used.
[0035]
  The optical pickup 3 has an objective lens 4 capable of fine reciprocation (swing) in a range of several tens of μm in a direction perpendicular to the surface of the disk 1. Then, the optical pickup 3 irradiates the magnetic head 2 with a light beam while reciprocating the objective lens 4 in a direction perpendicular to the surface of the disk 1 at a fixed period during alignment. As a result, the focusing position of the light beam reciprocates in the vicinity of the surface of the magnetic head 2 in a direction perpendicular to the surface of the magnetic head 2 at a constant period.
[0036]
  Further, the optical pickup 3 has a light detection unit (not shown) for measuring the reflected light from the magnetic head 2 obtained by irradiating the light beam while reciprocating the objective lens 4 in this way. Is provided. The light detection unit measures the intensity of the reflected light from the magnetic head 2 that is incident in the direction opposite to the irradiation direction of the light beam from the optical pickup 3, and outputs a reflected light signal representing the intensity of the reflected light to the optical pickup driver 11. To output from.
[0037]
  The magnetic head 2 is to align the magnetic head 2 and the optical pickup 3 with a magnetic head Z stage (not shown) for moving the magnetic head 2 in a direction (height direction) perpendicular to the disk 1. A magnetic head XY stage (moving means) 5 and a magnetic head XY piezo stage (moving means) 6 for moving the magnetic head 2 along an XY plane parallel to the disk 1 are mounted via a jig. Yes. The magnetic head XY stage 5 performs a rough movement, and the magnetic head XY piezo stage 6 performs a precise movement.
[0038]
  On the other hand, the optical pickup 3 has a focus adjustment Z stage (not shown) for moving the magnetic head 2 in the Z-axis direction perpendicular to the disk 1 to adjust the focus of the optical pickup 3, and the rotation center of the disk 1. The optical pickup 3 is mounted on an optical pickup XY stage 7 for moving the optical pickup 3 along a plane parallel to the disk 1 via a jig so as to align the center (rotation center) of the optical pickup 3.
[0039]
  These stages (Z stage for magnetic head, XY stage 5 for magnetic head, XY piezo stage 6 for magnetic head 6, Z stage for focus adjustment, and XY stage 7 for optical pickup) are arranged from the outer diameter of disk 1 to disk 1. It is attached to an X slide stage 9 that is movable in the X-axis direction toward the center. Thereby, these stages can move from the outer diameter of the disk 1 to an arbitrary position on the radius toward the center of the disk 1.
[0040]
  Here, the magnetic head 2 and the optical pickup 3 are aligned by moving the magnetic head 2 with respect to the optical pickup 3 using the magnetic head XY stage 5 and the magnetic head XY piezo stage 6. did. The reason is that the optical pickup 3 is generally less exchanged than the magnetic head 2, and it is not necessary to readjust the optical pickup 3 once the center of the optical pickup 3 is aligned with the center of the disk 1. 2 is a light weight and a small load on the stage. However, the magnetic head 2 and the optical pickup 3 may be aligned by moving the optical pickup 3 relative to the magnetic head 2.
[0041]
  In order to precisely position the magnetic head 2 and the optical pickup 3, it is necessary to move the magnetic head 2 precisely. Therefore, it is necessary to select a magnetic head XY stage 5 and a magnetic head XY piezo stage 6 that ensure precision (resolution) and a minimum movement amount capable of precise positioning.
[0042]
  Further, the magnetic head XY stage 5 and the magnetic head XY piezo stage 6 have sufficient strokes so as to cope with exchange of the magnetic head 2, change of specifications of the magnetic head 2, variation in dimensions of the magnetic head 2, etc. You need to choose what you have.
[0043]
  Here, an XY piezo stage with a positioning accuracy of 10 nm (reproducibility of 40 nm) and a stroke of 100 μm is used as the XY piezo stage 6 for fine movement magnetic head, and a minimum scale (minimum movement amount) is used as the XY stage 5 for magnetic head for coarse movement. ) An XY stage with 1 μm and a stroke of 12 mm was used, and these were stacked. As the Z stage for the magnetic head, a Z stage having a minimum scale of 10 μm and a stroke of 6 mm was used.
[0044]
  The magnetic head XY stage 5 and the magnetic head XY piezo stage 6 are connected via a XY stage / XY piezo stage 13, and the spindle 8 and the X slide stage 9 are connected via a spindle / X slide stage driver 14, respectively. Control means) 15 and controlled by a control computer 15.
[0045]
  The control computer 15 controls the optical pickup 3 via the optical pickup driver 11 and also controls the magnetic head 2 via the magnetic signal Read / Write driver (magnetic signal read / write driver) 10. Further, the control computer 15 takes in the reflected light signal output from the optical pickup driver 11 via a signal measuring device 12 such as an oscilloscope. Further, the control computer 15 takes in the magnetic signal output from the magnetic signal Read / Write driver 10 via the signal measuring device 12.
[0046]
  The control computer 15 controls the position of the magnetic head 2 based on the reflected light signal. That is, the control computer 15 first controls the optical pickup 3 to irradiate a light beam via the optical pickup driver 11, and the magnetic head 2 is moved by the magnetic head XY stage 5 and the magnetic head XY piezostage 6. While moving relative to the optical pickup 3, the reflected light signal representing the measurement result of the change in the reflected light signal is taken from the signal measuring device 12. Next, the control computer 15 identifies the relative position of the magnetic head 2 with respect to the optical pickup 3 based on the measurement result of the reflected light signal change, and based on the identified relative position, the magnetic head XY stage 5 and the magnetic head The magnetic head 2 is aligned with the optical pickup 3 by the XY piezo stage 6.
[0047]
  Next, the disk 1 used in the alignment method of the present embodiment and the magnetic head 2 that performs alignment will be described in detail. As the disk 1 used in the alignment method of the present embodiment, it is preferable to use a disk that is transparent to the light beam emitted from the optical pickup 3. As a result, the light beam reaches the magnetic head 2 without being attenuated. For this reason, the change in reflected light intensity can be measured without impairing the dynamic range, and the alignment between the magnetic head 2 and the optical pickup 3 is facilitated.
[0048]
  In the present specification, a “disk transparent to a light beam” usually refers to light having a wavelength of 400 nm or more at a thickness to be used (in this embodiment, intended to be about 0.6 mm). A disk showing a transmittance of at least 80% with respect to the disk.
[0049]
  Here, as the disk 1, a 2.5-inch diameter transparent glass disk (outer diameter 65 mm, inner diameter 20 mm, thickness 0) showing a transmittance of about 90% with respect to the light beam having a wavelength of 780 nm emitted from the optical pickup 3. .635 mm) was used. Since a transparent glass disk having a transmittance of about 90% with respect to the light beam having a wavelength of 780 nm emitted from the optical pickup 3 is used, the light beam emitted from the optical pickup 3 is not attenuated on the magnetic head 2. Is irradiated.
[0050]
  Note that a protective film, such as an amorphous carbon film or a diamond-like carbon film, usually used on the outermost surface of the magnetic recording medium for HDD may be formed on the surface of the disk 1 on the magnetic head 2 side. Thereby, it is possible to obtain a sufficient reflected light intensity while protecting the surface of the disk 1.
[0051]
  Similarly, on the surface of the disk 1 on the side of the magnetic head 2, a lubricant usually used for the outermost surface of the HDD magnetic medium, such as perfluoropolyether, Z-DOL (trade name), or the like is a film of about 2 nm. You may apply | coat so that it may become thickness. Since the lubricant has a refractive index almost the same as that of glass and a thin film thickness, it does not cause a decrease in reflected light intensity.
[0052]
  Since these protective films and lubricant films do not decrease the reflected light intensity, it is possible to perform alignment while the magnetic head 2 is levitated using the disk 1 on which the protective film and / or lubricant is formed.
[0053]
  As the magnetic head 2 of the present embodiment, as shown in FIG. 2, a composite MR in which a recording / reproducing element unit 40 including a thin film head as a recording element and an MR element (MR head) as a reproducing element is formed. A head was used. As the slider 16, a 50% slider having a length (length in the Y-axis direction) 2.0 mm × width (length in the X-axis direction) 1.6 mm × thickness 0.43 mm was used. A slider ABS (Air-Bearing Surface) 17 that is a surface of the slider 16 facing the disk 1 is parallel to the disk 1. The X-axis direction is the radial direction of the disk 1, and the Y-axis direction is the tangential direction of the disk 1.
[0054]
  When the position of the recording / reproducing element unit 40 at the slider ABS 17 of the slider 16 is measured with a microscope, the distance in the X-axis direction from the corner A of the slider 16 to the center of the recording / reproducing element unit 40 (as shown in FIG. 2) The X-coordinate difference) was about 215 μm, and the distance in the Y-axis direction from the side end surface A of the slider 16 to the write pole 18 (Y-coordinate difference) was about 26.5 μm. In the magnetic head 2, the size of the slider 16 and the position of the recording / reproducing element section 40 generally vary by about ± several tens μm from product to product.
[0055]
  As the recording / reproducing element section 40, a write pole 18 that is a part of a thin film head (recording element), a read pole 19 that is a part of an MR element (reproducing element) and also serves as a shield for the thin film head (recording element), FIG. 3 shows a state in which the bottom shield 20 is arranged from the top in this order. In addition, a write gap 21 is formed between the write pole 18 and the read pole 19. On the other hand, an MR element (not shown) is formed between the Read pole 19 and the bottom shield 20, that is, in the Read gap 22 sandwiched between the Read pole 19 and the bottom shield 20.
[0056]
  The dimensions of the recording / reproducing element unit 40 are the height of the write pole 18 (the length in the Y-axis direction) is 3.5 μm, and the length of the write gap 21 (the distance between the write pole 18 and the read pole 19). 0.35 μm, Read pole 19 height (Y-axis length) is 3.5 μm, Read gap 22 length (distance between Read pole 19 and bottom shield 20) is 0.22 μm, bottom shield The height 20 (length in the Y-axis direction) is 2.5 μm, the width of the write pole 18 (length in the X-axis direction) is 5 μm, the width of the read pole 19 (length in the X-axis direction) is 104 μm, the bottom The width of the shield 20 (the length in the X-axis direction) is 120 μm.
[0057]
  In the magnetic head 2 of the present embodiment, the write pole 18, read pole 19 and bottom shield 20 of the recording / reproducing element unit 40 are mainly made of a metal film such as a NiFe alloy, while the slider ABS 17 is made of Al.₂ O_Three -Made of TiC (altic) substrate, the other parts are mainly Al₂O_Three It consists of a membrane. Therefore, in the magnetic head 2 of the present embodiment, the reflectivity of the write pole 18, the read pole 19 and the bottom shield 20 of the recording / reproducing element unit 40 is high, and the reflectivity of other portions is low.
[0058]
  Next, a method for aligning the magnetic head 2 and the optical pickup 3 according to this embodiment will be described. First, at the time of alignment, the optical pickup 3 is arranged so that the center of the light beam irradiated onto the disk 1 from the optical pickup 3 comes to a location about 29 mm away from the center of the disk 1. Further, the disk 1 disposed between the magnetic head 2 and the optical pickup 3 is rotated at a rotational speed of 3600 rpm, and the magnetic head 2 is levitated away from the disk 1. Here, the linear velocity of the disk 1 was about 10.93 m / s, and the flying height of the magnetic head 2 (distance from the disk 1) was about 50 nm.
[0059]
  By rotating the disk 1 and flying the magnetic head 2 away from the disk 1 in this way, not only can the alignment be performed under the same conditions as the actual device, but also the disk 1 and the magnetic head 2 during the alignment. Can prevent the MR element of the magnetic head 2 from being damaged by static electricity.
[0060]
  Next, while continuing the rotation of the disk 1 and the flying of the magnetic head 2, the magnetic head 2 is moved so that the positional relationship between the magnetic head 2 and the optical pickup 3 in the direction parallel to the surface of the magnetic head 2 changes. The optical pickup 3 irradiates the magnetic head 2 with a light beam. Then, a change in the intensity of the reflected light from the magnetic head 2 is measured by the signal measuring device 12 through the optical pickup driver 11 to obtain a reflected light signal representing the measured change in the intensity of the reflected light. At this time, the irradiation of the light beam is performed so that the focused position of the light beam is near the surface of the magnetic head 2. Thereby, even if the magnetic head 2 is levitated, the reflected light from the magnetic head 2 can be obtained efficiently.
[0061]
  The power of the light beam must be as low as possible so that reflected light with sufficient intensity can be obtained and the MR element of the magnetic head 2 is not deteriorated. The reflected light having a sufficient intensity can be obtained at 1 mW at which the MR element 2 does not deteriorate.
[0062]
  Further, when the light beam is irradiated from the optical pickup 3, the objective of the optical pickup 3 is reciprocated in the vertical direction with respect to the surface of the magnetic head 2 near the surface of the magnetic head 2. The lens 4 is reciprocated at a predetermined period in a direction perpendicular to the surface of the disk 1. Thereby, also in the magnetic gap part (Write gap 21 and Read gap 22) of the magnetic head 2, and also when the flying height of the magnetic head 2 changes due to a difference in the linear velocity of the disk 1, surface fluctuation, disturbance, etc. The light beam is always focused on the surface of the magnetic head 2 within the moving range of the objective lens 4. For this reason, it is possible to avoid the reflected light intensity from fluctuating due to factors other than the reflectance change without performing focus control. As a result, accurate positioning can be stably performed.
[0063]
  By irradiating a light beam from the optical pickup 3 while reciprocating the objective lens 4, a reflected light signal having a peak at a predetermined cycle is obtained as shown in FIG. 4B. The peak of the reflected light signal is detected when the focus error signal shown in FIG. 4A changes from negative to positive or from positive to negative, that is, when the light beam is focused on the magnetic head surface. Therefore, the peak value of this reflected light signal represents the reflected light signal when focused on the surface of the magnetic head, and accurately reflects the reflectivity of the magnetic head 2.
[0064]
  At this time, when the light beam is reflected by the write pole 18, the read pole 19, and the bottom shield 20 of the recording / reproducing element unit 40 having a high reflectance, as shown in FIG. While a reflected light signal having a peak value is obtained, when the light beam is reflected by the slider ABS 17 having a low reflectance, the reflected light signal having a lower peak value is obtained as shown in FIG. can get. Here, there is a signal difference of about 1 V between the peak value of the reflected light signal from the write pole 18, the read pole 19 and the bottom shield 20 of the recording / reproducing element unit 40 and the peak value of the reflected light signal from the slider ABS 17. Is obtained. Therefore, it can be seen that the position of the recording / reproducing element unit 40 and the position of the slider ABS 17 in the magnetic head 2 can be clearly distinguished.
[0065]
  Thereafter, the control computer 15 identifies the positional relationship between the magnetic head 2 and the optical pickup 3 in the direction parallel to the surface of the magnetic head 2 based on the change in the peak value of the reflected light signal. Finally, based on the identification result, the positional relationship in the direction parallel to the surface of the magnetic head 2 is adjusted by the magnetic head XY stage 5 and the magnetic head XY piezo stage 6.
[0066]
  As described above, in the alignment method of the present embodiment, the magnetic head 2 and the optical pickup 3 are based on the peak value of the reflected light signal that represents the intensity of the reflected light when focused on the surface of the magnetic head 2. Since the positional relationship in the direction parallel to the surface of the magnetic head 2 is adjusted, accurate positioning can be performed stably.
[0067]
  Further, according to the above method, it is not necessary to perform focus control, and it is not necessary to interpose an adjusting disk on which a semitransparent film for focusing is formed between the magnetic head 2 and the optical pickup 3. Therefore, the reflected light of the magnetic head 2 when focused on the surface of the magnetic head 2 can reach the optical pickup 3 without being attenuated.
[0068]
  Therefore, the intensity of the reflected light when focused on the surface of the magnetic head 2 can be measured with a wider dynamic range. Therefore, the position of the magnetic head 2 is identified based on the change in the reflectance of the surface of the magnetic head 2, particularly the reflection of the write pole 18, read pole 19, bottom shield 20 and slider ABS 17 of the recording / reproducing element unit 40. The recording / reproducing element unit 40 and the slider ABS 17 can be accurately discriminated based on the rate difference. As a result, even the position of the magnetic gap (Write gap 21 and Read gap 22) of the magnetic head 2 smaller than the light beam diameter can be identified, and accurate alignment can be performed.
[0069]
  Next, a procedure for performing alignment using the write pole 18, read pole 19, and reflected light signal difference between the bottom shield 20 and the slider ABS 17 of the MR element section 40 of the magnetic head 2 obtained in this way is described. This will be described in detail.
[0070]
  (1) First, the reflected light signal is measured while moving the magnetic head 2 from the position where the reflected light signal is not detected in the X-axis direction and the Y-axis direction shown in FIG. At this time, when the light beam first hits the slider 16, a reflected light signal corresponding to the reflectance of the slider ABS 17 is measured. Therefore, when the magnetic head 2 is moved in the X-axis direction, the reflected light signal corresponding to the reflectance of the slider ABS 17 is first measured, and when the magnetic head 2 is moved in the X-axis direction, the slider ABS 17 The Y coordinate at which the reflected light signal corresponding to the reflectance is first measured is obtained, and the position of the corner A that is the closest corner of the slider 16 is identified by these X coordinate and Y coordinate.
[0071]
  (2) Next, the magnetic head 2 is moved in the X-axis direction in accordance with a distance (here, 215 μm) in the X-axis direction from the angle A of the slider 16 to the center of the recording / reproducing element unit 40 measured in advance with a microscope or the like. Next, the magnetic head 2 is moved in the Y-axis direction according to the distance in the Y-axis direction (here, 26.5 μm) from the corner A of the slider 16 to the write pole 18. Thereby, the center of the magnetic head 2 and the center of the optical pickup 3 are aligned with an error within a range of several tens of μm. The movement and scanning of the magnetic head 2 in the procedures (1) and (2) are roughly performed by the magnetic head XY stage 5. On the other hand, the movement and scanning of the magnetic head 2 in the following procedure are precisely performed by the magnetic head XY piezo stage 6.
[0072]
  (3) Further, the magnetic head 2 is scanned in the Y-axis direction (track direction) shown in FIG. 2 or 3 to identify the positions (Y-coordinates) of the read pole 19 and the bottom shield 20 in the Y-axis direction.
[0073]
  (4) After moving the magnetic head 2 so that the light beam 23 (see FIG. 3) projected on the magnetic head 2 is positioned on the read pole 19, the magnetic head 2 is moved in the X-axis direction (track width direction). While scanning, the reflected light signal from the Read pole 19 is measured, and the position of the end of the Read pole 19 closer to the corner A of the slider 16 is identified.
[0074]
  (5) A position advanced in the X-axis direction by a distance ½ of the width of the read pole 19 measured in advance from the end of the read pole 19 closer to the corner A of the identified slider 16, that is, along the Y-axis direction. The magnetic head 2 is moved in the X-axis direction to a position predicted to be on the center line of the magnetic head 2.
[0075]
  (6) The magnetic head 2 is moved in the Y-axis direction so that the light beam 23 is positioned at the predicted position of the write pole 18.
[0076]
  (7) The reflected light signal is measured while scanning the magnetic head 2 in the X-axis direction, and the positions of both ends of the write pole 18 in the X-axis direction are identified.
[0077]
  (8) As shown in FIG. 3, the light beam 23 is positioned on the center line of the magnetic head 2 along the Y-axis direction so that the light beam 23 is positioned in the middle of the positions of both ends of the identified write pole 18. The magnetic head 2 is moved in the X-axis direction so as to be positioned.
[0078]
  (9) The magnetic head 2 is scanned in the Y-axis direction along the identified center line of the magnetic head 2 along the Y-axis direction, and the write pole 18, the read pole 19 and the bottom shield 20 are positioned in the Y-axis direction. And the positions of the write gap 21 and the read gap 22 in the Y-axis direction are identified from these identification results.
[0079]
  (10) The position in the X-axis direction of each part (Write pole 18, Read pole 19, bottom shield 20, Write gap 21, and Read gap 22) of the magnetic head 2 obtained by the procedures of (7) to (9) Based on the position in the Y-axis direction, the magnetic head 2 is moved so that the light beam 23 is positioned at a desired position of the magnetic head 2, for example, the read gap 22.
[0080]
  Based on the above alignment procedures (1) to (10), the width of the write pole 18, the height of the write pole 18, the height of the read pole 19, and the height of the bottom shield 20 for the magnetic head 2 having the specifications described above. Was identified.
[0081]
  As a result, the width of the write pole 18 is 4.72 μm (5.0 μm), the height of the write pole 18 is 3.55 μm (3.5 μm), the height of the read pole 19 is 3.49 μm (3.5 μm), The height of the bottom shield 20 was identified as 2.32 μm (2.5 μm). The numerical values in parentheses are measured values with a microscope or head manufacturer's specification values.
[0082]
  The error of each numerical value of the width of the write pole 18, the height of the write pole 18, the height of the read pole 19, and the height of the bottom shield 20 identified by the alignment method of the present embodiment is 0.28 μm, It can be seen that they are sufficiently small, 0.05 μm, 0.01 μm, and 0.18 μm.
[0083]
  Further, the magnetic heads 2 of other specifications were aligned in the same procedure, and the above numerical values were identified. As a result, the width of the write pole 18 is 1.86 μm (1.8 μm), the height of the write pole 18 is 3.62 μm (3.5 μm), the height of the read pole 19 is 2.47 μm (2.5 μm), The height of the bottom shield 20 was identified as 2.69 μm (2.5 μm). The numerical values in parentheses are measured values with a microscope or head manufacturer's specification values.
[0084]
  Similarly, it can be seen that the errors of the identified numerical values are sufficiently small, 0.06 μm, 0.12 μm, 0.03 μm, and 0.19 μm, respectively. Therefore, it can be seen that alignment can be performed corresponding to the magnetic heads 2 of various specifications.
[0085]
  In the above alignment apparatus, it was confirmed that no positional deviation occurred even when the magnetic head 2 and the optical pickup 3 were moved by the X slide stage 9 after alignment by the above procedure.
[0086]
  As long as the magnetic head 2 and the optical pickup 3 are not replaced, the positional shift caused by the activation of the alignment apparatus and the initialization of the drive unit of each XY stage (magnetic head XY stage 5 and magnetic head XY piezo stage 6) It is as small as about 1-2 μm. Therefore, at the time of starting the alignment apparatus, the alignment is completed only by performing the steps (6) to (10) described above after moving the magnetic head 2 to the position aligned at the previous use.
[0087]
  As described above, the alignment method according to the present embodiment has a magnetic gap (Write gap 21 and Read gap 22) of the magnetic head 2 that is narrower than the light beam at a sub-μm level with good reproducibility. Since the size and position can be identified by detection, precise alignment is possible.
[0088]
  In the present embodiment, a composite MR head is used as the magnetic head 2, but other magnetic heads such as a GMR head, a MIG (Metal-In-Gap) head, and a thin film head may be used as the magnetic head. In this embodiment, the optical pickup 3 that irradiates a light beam having a wavelength of 780 nm is used. However, an optical pickup that irradiates a blue laser beam having a wavelength of about 410 nm can also be used.
[0089]
  [Reference example]
  Alignment method and alignment apparatus for magnetic head and optical headReference example6 will be described below with reference to FIGS. For convenience of explanation, members having the same functions as those shown in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
[0090]
  BookReference exampleIn this alignment method, a magnetic disk (recording medium) in which a magnetic film is formed on the glass disk used in the first embodiment is used as the disk 1 instead of the glass disk used in the first embodiment. The magnetic film may be formed on at least one side.
[0091]
  As the magnetic film of the disk 1, it is preferable to use a ferrimagnetic film having a large coercive force and temperature change in magnetization. As a result, the change in the amount of magnetic signal becomes large, so that it is easy to determine whether or not recording is possible, and it is possible to precisely correct the position of the optimum read gap 22.
[0092]
  As the magnetic film of the disk 1, here, a TbFeCo film in which TbFeCo, which is an amorphous ferrimagnetic material, is formed on a glass disk so as to have a film thickness of 100 nm by an RF (high frequency) magnetron sputtering method was used. On the magnetic film, a carbon film was formed as a protective film to a thickness of 20 nm, and a lubricant was applied on the carbon film.
[0093]
  The composition of the magnetic film was analyzed by fluorescent X-ray and found to be Tb: Fe: Co = 24: 27: 49. Further, the residual magnetization (residual magnetism) Mr and the coercive force Hc of the magnetic film were measured by a VSM (Vibrating-Sample-Magnetometer) while changing the medium temperature (the temperature of the disk 1). The obtained result is shown in FIG. In FIG. 6, the horizontal axis represents the medium temperature, the left vertical axis represents the residual magnetization Mr, and the right vertical axis represents the coercive force Hc.
[0094]
  In the magnetic film, the residual magnetization Mr is 11 [emu / cc] at 25 ° C., 97 [emu / cc] at 100 ° C., 125 [emu / cc] at 150 ° C., and 148 [emu / cc] at 200 ° C. The temperature dependence is large at 165 [emu / cc] at 250 ° C. Also, the coercive force Hc is 10 × 10 at room temperature of 25 ° C.^Three [Oe] (800 kA / m) or more, 6.3 × 10 at 100 ° C.^Three[Oe] (504 kA / m), 3.6 × 10 at 150 ° C.^Three [Oe] (288 kA / m), 1.8 × 10 at 200 ° C.^Three [Oe] (144 kA / m), temperature dependence of 550 [Oe] (44 kA / m) at 250 ° C. is large.
[0095]
  BookReference exampleThis alignment apparatus is obtained by changing only the control of the control computer 15. BookReference exampleThe control computer 15 applies a magnetic field from the magnetic head 2 to the magnetic film in order to record a magnetic signal on the disk 1 as a recording medium, and the magnetic field generated by the magnetic head 2 is the coercive force of the magnetic film. The optical pickup 3 is irradiated with a light beam so that the magnetic film is heated to a temperature below, and the magnetic head XY stage 5 and the magnetic head XY piezo stage are based on the result of the magnetic signal measurement by the magnetic head 2. 6 is controlled. BookReference exampleThen, instead of the optical pickup 3, an optical head that does not include a light detection unit may be used. Also bookReference exampleThen, the objective lens 4 may be fixed.
[0096]
  BookReference exampleIn the method of aligning the magnetic head 2 and the optical pickup 3, first, the disk 1 having the magnetic film is disposed between the magnetic head 2 and the optical pickup 3, the disk 1 is rotated, and the magnetic head 2 is mounted. Float from disk 1.
[0097]
  Next, in order to record a magnetic signal on the disk 1, a magnetic field in which the coercive force of the magnetic film is applied by the magnetic head 2 by light beam irradiation from the optical pickup 3 while applying a magnetic field from the magnetic head 2 to the magnetic film. The magnetic film is heated to the following temperature. Thereafter, the magnetic signal on the disk 1 is measured by the magnetic head 2.
[0098]
  The recording and measurement of the magnetic signal is repeated while moving the magnetic head 2 along a plane parallel to the surface of the magnetic head 2.
[0099]
  Then, the relative position of the magnetic head 2 with respect to the optical pickup 3 is identified by the control computer 15 based on the obtained measurement result, and the positional relationship between the magnetic head 2 and the optical pickup 3 is adjusted based on the identification result.
[0100]
  Specifically, for example, based on the result of measuring whether or not a magnetic signal is recorded on the disk 1 by the magnetic head 2, the recording possible range regarding the relative position of the magnetic head 2 with respect to the optical pickup 3 is identified. Then, the magnetic head 2 is moved to the center of the identified range along a plane parallel to the disk 1 by the magnetic head XY stage 5 and the magnetic head XY piezo stage 6.
[0101]
  Alternatively, an optical pickup that maximizes the magnetic signal amount based on the result of measuring the change in the amount of the magnetic signal reproduced (measured) by the magnetic head 2 while irradiating the light beam with the signal measuring device 12 such as an oscilloscope or a spectrum analyzer. 3 is identified, and the magnetic head 2 is moved to the identified position along the plane parallel to the disk 1 by the magnetic head XY stage 5 and the magnetic head XY piezo stage 6.
[0102]
  In this way, by adjusting the positional relationship between the magnetic head 2 and the optical pickup 3 based on the measurement result of the magnetic signal such as the presence / absence of the magnetic signal and the change in the magnetic signal amount, the magnetic head 2 and the optical pickup 3 Can be aligned in an optimal positional relationship for recording magnetic signals.
[0103]
  The results of experiments to confirm the usefulness of the above method are shown below. Using the disk 1 having the above configuration, the magnetic head 2 and the optical pickup 3 are irradiated with the light beam at the position of the write gap 21 by the method described in the first embodiment using the alignment apparatus of the first embodiment. Then, magnetic signals were recorded while irradiating a light beam. The conditions at this time were such that the rotational speed of the disk 1 was 3600 rpm, the linear velocity of the disk 1 was about 10.93 m / s, and the flying height of the magnetic head 2 was about 50 nm.
[0104]
  First, when an attempt was made to write a magnetic signal without light irradiation, the magnetic signal was not measured. That is, recording could not be performed. As described above, the coercive force Hc of the magnetic film of the disk 1 is 6.3 × 10 at room temperature as described above.^Three This is because [Oe] (504 kA / m) is larger than the write magnetic field of the magnetic head 2.
[0105]
  Next, when a magnetic signal was written while irradiating a light beam with a power of 6 mW from the optical pickup 3, the recorded magnetic signal was measured. This shows that recording was possible because the temperature of the irradiated region increased due to irradiation with the light beam of 6 mW, and the coercive force Hc of the magnetic film of the disk 1 decreased below the writing magnetic field of the magnetic head 2. ing. This simultaneously confirms that the alignment method described in Embodiment 1 is useful.
[0106]
  Further, when the magnetic head 2 was moved in the track width direction (X-axis direction) with respect to the optical pickup 3, recording could not be performed when the magnetic head 2 moved ± 2.3 μm, and the magnetic signal was not measured. This is because the region heated by the light beam from the optical pickup 3 deviates from the region where the magnetic field of the magnetic head 2 acts, so that the temperature of the region decreases, and the coercive force of the magnetic film is recorded on the magnetic head 2. This is thought to be because it became larger than the magnetic field.
[0107]
  From these, the magnetic head 2 can be identified as being within a range of ± 2.3 μm of the initial light beam irradiation position. Therefore, the width (length in the X-axis direction) of the magnetic head 2 can be identified as 4.6 μm. The specification value of the width of the magnetic head 2 is 5.0 μm.
[0108]
  Thus, using the magnetic head 2 and the optical pickup 3 that have been aligned by the alignment method of the first embodiment, whether or not recording is possible, that is, whether or not a magnetic signal is measured, It can be seen that it is possible to determine whether the light irradiation and the recording magnetic field are acting on the same area of the disk 1 and to identify the position of the magnetic head 2.
[0109]
  Next, after recording the magnetic signal while irradiating the light beam, the magnetic head 2 is moved so that the light beam is irradiated to the position of the read gap 22 identified by the alignment method of Embodiment 1, and the light beam is moved. The magnetic signal was reproduced while irradiating. It was confirmed that when the power of the light beam was increased from 1 mW to 6 mW, the amount of the reproduced magnetic signal increased accordingly. The reproduced magnetic signal is obtained by measuring the carrier level with a signal measuring device 12 such as a spectrum analyzer.
[0110]
  Further, the magnetic head 2 was scanned in the track direction (Y-axis direction) while irradiating the light beam at 6 mW, and the change in the amount of the reproduced magnetic signal at each position was measured. The measurement results are shown in FIG. In FIG. 7, the relative position of the magnetic head 2 with respect to the optical pickup 3 in the track direction (Y-axis direction) is on the horizontal axis, and the reproduced magnetic signal is on the vertical axis.
[0111]
  In FIG. 7, the origin O on the horizontal axis is the initial position of the magnetic head 2 that is aligned so that the read gap 22 is irradiated with the light beam, and the + direction is the running direction of the disk 1. In other words, the region where the horizontal axis is + indicates that the magnetic head 2 is located at a position where the reproduction region is irradiated with the light beam before the read region reaches the position of the read gap 22. On the other hand, the region where the horizontal axis is − represents that the magnetic head 2 is located at a position where the reproduction ramp is subjected to the light beam irradiation after the position of the read gap 22.
[0112]
  The moving distance of the magnetic head 2 at which the reproduction magnetic signal is reduced by half with respect to the maximum value was 1.12 μm in the + direction and −0.62 μm in the − direction. The movement distance that is halved in the + direction and the-direction is different because the temperature of the reproduction area must be raised in advance, and the temperature distribution is extended in the running direction of the disk 1 and the position that shows the maximum temperature is also shifted. It is considered that the light beam diameter is 1.27 μm. This temperature distribution varies depending on the power of the light beam, the linear velocity of the disk 1, the reflectance of the disk 1, and the like.
[0113]
  In addition, since the reproduction magnetic signal level changes depending on the position of the Read gap 22, a slight deviation in the position of the Read gap 22 from the optimum position of the Read gap 22 due to the temperature distribution, which is a problem in actual device operation, is reproduced. It can be seen that the correction can be made by moving to the position where the magnetic signal is most greatly obtained.
[0114]
  BookReference exampleIn this example, a ferrimagnetic film made of TbFeCo is used as the magnetic film of the disk 1, but a magnetic film having another composition may be used as the magnetic film of the disk 1. The ferrimagnetic film other than the TbFeCo film is not particularly limited, but a TbCo film, a DyCo film, or the like is easy to use.
[0115]
  Also bookReference exampleThis alignment apparatus is useful as both an evaluation device and an actual device such as a magnetic disk device or a magneto-optical disk device, and enables the development of a high-density memory device that combines optical technology and magnetic technology. .
[0116]
  Furthermore, in the above description, the precise alignment of the position of the Read gap 22 has been described, but the precise alignment of the position of the Write gap 21 from which a reproduction signal can be obtained can be performed by the same method.
[0117]
  Also bookReference exampleIn this case, a composite MR head is used as the magnetic head 2, but another magnetic head such as a GMR head, a MIG (Metal-In-Gap) head, or a thin film head may be used as the magnetic head 2. Also bookReference exampleIn this example, the optical pickup 3 that emits a light beam having a wavelength of 780 nm is used. However, an optical pickup that emits blue laser light having a wavelength of about 410 nm can also be used.
[0118]
(Other configurations)
This reference example may have the following configuration.
[0119]
(Configuration 1)
An alignment method for aligning a magnetic head for generating a magnetic field and measuring a magnetic signal and an optical head for irradiating a light beam so as to face each other, and having a magnetic film After the medium is placed between the magnetic head and the optical head, in order to record a magnetic signal on the recording medium, a magnetic field is applied to the magnetic film from the magnetic head, while the magnetic film is irradiated by a light beam from the optical head. The magnetic film is heated to a temperature at which the coercive force is equal to or less than the magnetic field applied by the magnetic head, and then the magnetic signal on the recording medium is measured by the magnetic head. Based on the obtained measurement results, the magnetic head and the optical head Adjusting the positional relationship between the magnetic head and the optical head.
[0120]
(Configuration 2)
A method of aligning a magnetic head and an optical head according to Configuration 1, wherein a ferrimagnetic film is used as the magnetic film.
[0121]
(Configuration 3)
An alignment apparatus for aligning a magnetic head for generating a magnetic field and measuring a magnetic signal and an optical head for irradiating a light beam so as to face each other, the magnetic head and the optical head A recording medium having a magnetic film disposed therebetween, moving means for moving at least one of the magnetic head and the optical head so that the positional relationship between the magnetic head and the optical head changes, and a magnetic signal on the recording medium In order to record, a magnetic beam is applied from the optical head so that the magnetic film is heated to a temperature at which the coercive force of the magnetic film is equal to or lower than the magnetic field generated by the magnetic head while applying a magnetic field from the magnetic head to the magnetic film. And a control means for controlling the moving means based on the result of measurement of the magnetic signal by the magnetic head. The alignment device of the head.
[0122]
The configurations described in configurations 1, 2 and 3 were found by the inventors of the present invention as a result of studying the temperature rising region by the light beam with the magnetic head itself.
[0123]
In order to solve the above-described problem, the magnetic head and optical head alignment method described in Configuration 1 includes a magnetic head for generating a magnetic field and measuring a magnetic signal, and light for irradiating a light beam. An alignment method in which a head is disposed so as to face each other, and a recording medium having a magnetic film is disposed between the magnetic head and the optical head, and then a magnetic signal is recorded on the recording medium. Therefore, while applying a magnetic field from the magnetic head to the magnetic film, the magnetic film is heated to a temperature at which the coercive force of the magnetic film is less than or equal to the magnetic field applied by the magnetic head by light beam irradiation from the optical head, and then the magnetic film The magnetic signal on the recording medium is measured by the head, and the positional relationship between the magnetic head and the optical head is adjusted based on the obtained measurement result.
[0124]
According to the above method, by adjusting the positional relationship between the magnetic head and the optical head based on the measurement result of the magnetic signal on the recording medium, the magnetic head and the optical head are brought into the optimal positional relationship for recording the magnetic signal. Can be aligned.
[0125]
For example, in the recording medium, the coercive force of the recording medium is less than or equal to the magnetic field generated by the magnetic head only in the region where the magnetic field is applied and the temperature is increased by light irradiation, and the magnetic signal is recorded. Therefore, if it is determined from the measurement result of the magnetic head whether or not a magnetic signal is recorded on the recording medium, whether or not both the light irradiation and the magnetic field act on the same area, that is, the light beam from the optical head. It can be determined whether or not the magnetic field generating part (magnetic core) of the magnetic head exists on the center line.
[0126]
Therefore, if the positional relationship between the magnetic head and the optical head is adjusted based on whether or not a magnetic signal is recorded on the recording medium, the magnetic head and the optical head have an optimal positional relationship for recording the magnetic signal. Can be aligned.
[0127]
Further, the amount of magnetic signal recorded on the recording medium changes according to the temperature of the recording area to be heated. Therefore, if the recorded magnetic signal is measured (reproduced) with a magnetic head while irradiating a light beam, the amount of magnetic signal can be changed according to the temperature distribution in the recording area. Can be used to measure changes in the amount of magnetic signal. Then, if the position where the magnetic signal amount is the largest is detected based on the measurement result, the center position of the magnetic field generation unit (magnetic core) of the magnetic head can be accurately identified.
[0128]
Therefore, if the positional relationship between the magnetic head and the optical head is adjusted based on the change in the magnetic signal amount, the magnetic head and the optical head can be accurately aligned to the optimal positional relationship for recording the magnetic signal. .
[0129]
In order to solve the above-described problem, the magnetic head and optical head alignment method described in Configuration 2 includes a ferrimagnetic film as the magnetic film in the alignment method of the magnetic head and optical head described in Configuration 3. It is characterized by using.
[0130]
According to the above method, by using a ferrimagnetic film as the magnetic film, the temperature change of the coercive force and magnetization of the magnetic film is increased, and the change of the magnetic signal amount can be increased. Therefore, the positional relationship between the magnetic head and the optical head can be adjusted more accurately based on the measurement result of the magnetic signal such as the presence / absence of the magnetic signal on the disk and the change in the magnetic signal amount.
[0131]
In order to solve the above-described problems, the magnetic head and optical head alignment apparatus described in Configuration 3 generates a magnetic field and measures a magnetic signal, and light for irradiating a light beam. An alignment apparatus that positions and aligns a head so as to face each other, and a positional relationship between a recording medium having a magnetic film disposed between a magnetic head and an optical head, and the magnetic head and the optical head At least one of the magnetic head and the optical head And a moving means for moving the magnetic head and a magnetic signal on the recording medium, while applying a magnetic field from the magnetic head to the magnetic film, to a temperature at which the coercive force of the magnetic film is less than or equal to the magnetic field generated by the magnetic head. The optical head is irradiated with a light beam so that the magnetic film is heated, and control means for controlling the moving means based on the result of measurement of the magnetic signal by the magnetic head is provided.
[0132]
According to the above configuration, a magnetic head and optical head alignment apparatus capable of automatically executing the method described in Configuration 1 can be provided. Therefore, it is possible to provide an alignment device between the magnetic head and the optical head that can align the magnetic head and the optical head in an optimal positional relationship for recording magnetic signals.
[0133]
【The invention's effect】
  The present inventionPertaining toAs described above, the magnetic head and the optical head are aligned by providing the optical head with a light detection unit for measuring the intensity of the reflected light, and the focusing position of the light beam is close to the surface of the magnetic head. While the objective lens was reciprocated so as to reciprocate in the direction perpendicular to the surface, the optical head irradiated the light beam to measure the intensity of the reflected light from the magnetic head. In this method, the positional relationship between the magnetic head and the optical head is adjusted based on the intensity of the reflected light.
[0134]
  Therefore, the above method has an effect of providing an alignment method capable of stably performing accurate alignment.
[0135]
  The present inventionPertaining toAs described above, the method of aligning the magnetic head and the optical head rotates the reflected light intensity by placing a disk transparent to the light beam between the magnetic head and the optical head. At the same time, the magnetic head is lifted away from the disk.
[0136]
  Therefore, the above method can perform the alignment under the same conditions as the actual device, can prevent the magnetic head from being damaged during the alignment, and further facilitate the alignment between the magnetic head and the optical head. There is an effect that can be.
[0137]
  The present inventionPertaining toAs described above, the magnetic head and optical head alignment device drives the objective lens to reciprocate so that the focusing position of the light beam reciprocates in the direction perpendicular to the magnetic head surface near the magnetic head surface. And a moving means for moving at least one of the magnetic head and the optical head so that the positional relationship between the magnetic head and the optical head changes, and the optical head and the driving means are simultaneously operated and measured by the optical head. And a control unit that controls the moving unit based on a change in the intensity of the reflected light.
[0138]
  Therefore, the above-described configuration has an effect that it is possible to provide a magnetic head and optical head alignment device that can stably and automatically execute accurate alignment.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an embodiment of an alignment apparatus of the present invention.
FIGS. 2A and 2B are diagrams showing a magnetic head of the alignment apparatus, wherein FIG. 2A is a plan view showing an enlargement of the recording / reproducing element portion of the magnetic head, and FIG. 2B is a plan view showing the entire magnetic head. is there.
FIG. 3 is a plan view showing a recording / reproducing element portion of the magnetic head.
4A and 4B are graphs showing changes in signals measured in one embodiment of the alignment method of the present invention, wherein FIG. 4A is a graph showing changes in a focus error signal, and FIG. 4B is a change in reflected light signals. It is a graph which shows.
FIG. 5 is a graph showing changes in the reflected light signal from the magnetic head measured in one embodiment of the alignment method of the present invention, where (a) is a write pole, read pole, And (b) is a graph showing the reflected light signal from the slider ABS.
FIG. 6 is a graph showing changes in residual magnetization Mr and coercive force Hc of a TbFeCo film used in another embodiment of the alignment method of the present invention with temperature.
FIG. 7 is a graph showing a relationship between a magnetic head position measured in another embodiment of the alignment method of the present invention and a reproduced magnetic signal.
FIG. 8 is a cross-sectional view showing a magneto-optical disk device and an adjustment disk used in a conventional alignment method.
[Explanation of symbols]
    1 disc
    2 Magnetic head
    3 Optical pickup (optical head)
    4 Objective lens
    5 XY stage for magnetic head (moving means)
    6 XY piezo stage for magnetic head (moving means)
    7 XY stage for optical pickup
    8 Spindle
    9 X slide stage
  10 Magnetic signal Read / Write driver
  11 Optical pickup driver
  12 Signal measuring instrument
  13 XY stage / XY piezo stage driver
  14 Spindle / X slide stage driver
  15 Control computer (control means)
  16 50% slider
  17 Slider ABS
  18 Write pole
  19 Read Paul
  20 Bottom shield
  21 Write gap
  22 Read gap
  23 Light Beam
  24 Transparent substrate
  25 Translucent film
  26 Protective film
  27 Slider
  28 Magnetic core
  29 Incident light
  30 Reflected light
  31 Reflected light
  32 Reflected light
  33 Spindle motor
  34 discs
  35 Magnetic head
  40 Recording / reproducing element section

Claims (3)

An alignment method for aligning a magnetic head for generating a magnetic field and an optical head for irradiating a light beam through a movable objective lens so as to face each other,
The optical head is provided with a light detection unit for measuring the intensity of reflected light,
While moving the objective lens back and forth so that the focusing position of the light beam reciprocates in the direction perpendicular to the surface of the magnetic head near the surface of the magnetic head, the light beam is irradiated from the optical head to the magnetic head. Measure the intensity of reflected light with an optical head,
A method for aligning a magnetic head and an optical head, wherein the positional relationship between the magnetic head and the optical head is adjusted based on the measured intensity of reflected light.   The intensity of the reflected light is measured while a disk transparent to the light beam is placed between the magnetic head and the optical head and rotated, and the magnetic head is levitated away from the disk. The method of aligning a magnetic head and an optical head according to claim 1. A magnetic head for applying a magnetic field to the recording medium and an optical head for irradiating the magnetic head with a light beam through a movable objective lens and measuring the intensity of reflected light are arranged so as to face each other. An alignment device for performing alignment ,
Drive means for reciprocating the objective lens so that the focusing position of the light beam reciprocates in the direction perpendicular to the magnetic head surface near the magnetic head surface;
Moving means for moving at least one of the magnetic head and the optical head so that the positional relationship between the magnetic head and the optical head changes;
A position of the magnetic head and the optical head, wherein the optical head and the driving means are operated simultaneously, and a control means for controlling the moving means based on a change in the intensity of the reflected light measured by the optical head is provided. Alignment device .

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