JP2006127684A - Transfer method, apparatus, and inspection method for master disk - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transfer method, apparatus, and an inspection method for a master disk capable of discriminating a foreign material such as dust and fiber waste adhering to a master disk. <P>SOLUTION: An inspection method of master disks are used for magnetic transfer wherein a magnetic disk 46 to be transferred is supplied between a pair of master disks held by a pair of holders 22, the master disks are respectively pressed into contact with both sides of the magnetic disk to be transferred, a magnetic field is applied to the pressed magnetic disk to be transferred to respectively transfer the magnetic patterns on a pair of the master disks to both sides of the magnetic disk to be transferred. A light emission means emits an emission light in a way that the optical axis of the emission light takes an angle of 1 to 30 degrees with respect to a radial direction of an inspected part on the surface of the master disks and an imaging element images the reflected light of the emitted light to inspect a contaminated state of the surface of the master disks. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a transfer method, an apparatus, and a master disk inspection method, and in particular, prevents generation of defective products when transferring a magnetic information pattern such as format information from a master disk to a magnetic disk used in a hard disk device or the like. The present invention relates to a transfer method, an apparatus, and a master disk inspection method that are effective for this purpose.

  In recent years, magnetic disks (hard disks) used in hard disk drives, which have been rapidly spreading, are written with format information and address information before being installed in the drive after being delivered to the drive manufacturer by the magnetic disk manufacturer. It is common. Although this writing can be performed by a magnetic head, a method of batch transfer from a master disk in which these format information and address information are written is efficient and preferable.

  Conventionally, various proposals have been made as this type of magnetic transfer technology (see, for example, Patent Documents 1 to 3). Among these, Patent Document 1 proposes to improve work efficiency when performing magnetic transfer by bringing a master disk into close contact with both sides while automatically transporting a transfer target disk. Patent Document 2 proposes that the servo area of the master disk is formed to be more convex than the data area to prevent defects such as signal dropout of the transfer signal.

  However, such conventional techniques have also been pointed out that there are many transfer defects and transfer yields are poor, and that the master disk must be frequently replaced.

  In other words, when performing magnetic transfer, it is necessary to bring the master disk and the hard disk to be transferred (slave disk) into close contact, but if the cleanliness in this environment is poor, transfer may be caused by fine particles or dust, The surface of the master disk is often damaged.

  In particular, the repeated use of such a master disk makes it easy for dust, fiber waste, etc. generated in the surrounding environment to adhere to the surface of the master disk. If foreign matter such as dust or fiber scraps adheres to the surface of the master disk and is in close contact with the slave disk, the master disk and slave disk are not sufficiently in contact with each other within a predetermined range centered on the foreign matter, and transfer It tends to be defective. When the recorded signal is a servo signal, there is a problem that the tracking function is not sufficiently obtained and the reliability is lowered.

  In addition, by repeating the close contact between the master disk and the slave disk, the adhesion force of the foreign matter to the surface of the master disk is increased, and in the subsequent close transfer, it is likely to reproduce the same transfer defect. .

  Furthermore, the adhesion of the foreign matter to the surface of the master disk may cause a problem that the surface of the master disk is deformed or a surface of the master disk is damaged, and the normal function of the master disk is impaired.

On the other hand, as in Patent Document 3, in a method of inspecting a foreign substance on a master disk by irradiating a laser beam to an inspection site and inspecting a foreign substance on a master disk by using an image in which reflected light is acquired by rotational scanning of a line sensor, On the other hand, a proposal has been made in which the pattern groove portion is registered in advance in the image processing unit as a mask area at the stage of image processing, and the portion is masked to be separated from the convex defect portion due to the original foreign matter. Yes.
JP 2004-87099 A JP 2002-74655 A JP 2002-372501 A

  However, in the inspection by such a laser scattering method, when there are irregularities like the pattern part, the pattern part reflects light in the same manner as the foreign substance, and it is difficult to distinguish the pattern part from the foreign substance defect. Further, since the pattern portion must be masked, the servo area most important in quality cannot be inspected. Furthermore, since the convex portion of the pattern portion is formed higher than the data region, there is a problem that it is more easily affected.

  The present invention has been made in view of such circumstances, and it is possible to easily discriminate foreign matters such as dust and fiber waste from the master disk, and by correspondingly removing foreign matters, the life of the master disk can be easily obtained. It is an object of the present invention to provide a transfer method, an apparatus, and a master disk inspection method that can dramatically improve the productivity and improve the productivity of the contact transfer work.

  In order to achieve the above object, the present invention provides a disk holding means for holding a master disk having a large number of protruding patterns formed on its surface by a holder portion, and transferring the pattern of the master disk to a disk for transfer. The transfer light and the light irradiation means are irradiated with the irradiation light so that the optical axis of the irradiation light forms an angle of 0 to 30 degrees with respect to the radial direction of the inspected portion of the surface of the master disk. There is provided a transfer apparatus, comprising: an inspection unit configured to inspect a contamination state of the surface of the master disk by imaging reflected light of light with an image sensor.

  According to the present invention, in the inspection means for inspecting the contamination state of the surface of the master disk, the irradiation light is emitted so that the optical axis forms an angle of 0 to 30 degrees with respect to the radial direction in the inspected portion of the surface of the master disk. The reflected light of the irradiated light is imaged by the image sensor. Accordingly, it is possible to detect with high sensitivity the foreign matter on the specific pattern that has the most adverse effect on the quality while reducing the reflected light from the specific pattern on the master disk that is easily mistaken for the original foreign matter.

  The “angle of 0 to 30 degrees with respect to the radial direction in the inspected portion of the disk surface” includes an inclination angle with respect to the disk surface (plane) and an inclination angle with respect to a radius on the disk surface (plane), It means that the total inclination angle with respect to the radius line virtually drawn on the inspected portion of the surface of the disk is not less than 0 degrees and not more than 30 degrees.

  In addition, if the tilt angle of the optical axis is 0 degree, it is considered that the part to be inspected is not irradiated. However, since the light flux from the light irradiating means has a predetermined cross-sectional size, the part to be inspected is effectively irradiated. obtain.

  The present invention also includes a supplying step of supplying a transfer target disk so as to face a master disk having a large number of protruding magnetic layer patterns formed on the surface of the holder and held by the holder portion. A pressing process in which the master disk is clamped by being pressed against a transfer disk, a transfer process in which a magnetic pattern is applied to the holder portion to transfer a magnetic pattern on the master disk to the transfer target disk, and irradiation is performed by light irradiation means. The irradiation light is irradiated such that the optical axis of the light forms an angle of 0 to 30 degrees with respect to the radial direction of the inspection target portion on the surface of the master disk, and the reflected light of the irradiated light is imaged by an imaging device. And an inspection process for inspecting the contamination state of the surface of the master disk.

  To this end, the present invention provides a disk holding means for holding a master disk having a large number of protruding magnetic layer patterns formed on the surface thereof by a holder portion, and applying a magnetic field to the holder portion to Magnetic field applying means for transferring the magnetic pattern to the disk to be transferred, and the optical axis of the irradiated light from the light irradiating means so as to form an angle of 0 to 30 degrees with respect to the radial direction in the inspected portion of the surface of the master disk. There is provided a transfer device, comprising: an inspection unit that irradiates the irradiation light, images the reflected light of the irradiation light with an imaging device, and inspects the contamination state of the surface of the master disk.

  According to the present invention, in the inspection means for inspecting the contamination state of the surface of the master disk, the irradiation light is emitted so that the optical axis forms an angle of 0 to 30 degrees with respect to the radial direction in the inspected portion of the surface of the master disk. The reflected light of the irradiated light is imaged by the image sensor. Accordingly, it is possible to detect with high sensitivity the foreign matter on the specific pattern that has the most adverse effect on the quality while reducing the reflected light from the specific pattern on the master disk that is easily mistaken for the original foreign matter.

  The transfer disk refers to not only a magnetic disk but also various media such as an optical disk (including a magneto-optical disk).

  As described above, according to the present invention, the foreign matter on the specific pattern that has the most adverse effect on the quality is detected with high sensitivity while reducing the reflected light from the specific pattern on the master disk which is easily mistaken for the original foreign matter. it can.

  Hereinafter, preferred embodiments of a transfer method, apparatus, and master disk inspection method according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a perspective view showing an overall configuration of a magnetic transfer apparatus 10 which is a transfer apparatus according to the present invention, and FIG. 2 is a perspective view showing an outline of a disk cassette. The magnetic transfer apparatus 10 includes an apparatus main body 12 and a clean unit 14.

  The apparatus main body 12 includes a gantry 58, and a base 60 having a horizontal surface is provided on the gantry 58. Note that the side indicated by the thick arrow is the front surface of the apparatus main body 12. The apparatus main body 12 is surrounded by a clean unit 14 so as to ensure cleanliness.

  A clean air blowing unit (not shown) for supplying clean air to the inside of the apparatus is provided on the ceiling of the clean unit 14. This clean air blower unit is composed of an air filter such as a HEPA filter or ULPA filter and a blower fan, and can supply clean air having a cleanliness class of less than 100 by downflow to the inside of the apparatus.

  The clean air blown out from the clean air blowing unit is discharged to the outside. For this reason, as shown in FIG. 1, a plurality of exhaust fans 64 serving as exhaust means are disposed on the base 60 in empty areas where the mechanisms of the apparatus main body 12 are not disposed.

  At the front end of the base 60, a supply cassette 38 for accommodating the slave disk 40, which is a transfer target disk, and a discharge cassette 56 for collecting the slave disk 40 to which magnetic information has been transferred and discharged are provided. ing. The supply cassette 38 and the discharge cassette 56 have the same shape.

  As shown in FIG. 2, a plurality of supply cassettes 38 and discharge cassettes 56 can be accommodated with the surfaces of the slave disks 40 facing each other. That is, the slave disk 40 is inserted into each of the plurality of grooves 92, 92... Formed in parallel with the inner surface of the cassette, and the outer periphery of the slave disk 40 is defined by the surface formed by the grooves 92. The plurality of slave disks 40 are arranged so as to be spaced apart from each other.

  An index table 50 is attached to a substantially central portion of the upper surface of the base 60 so as to be rotatable with respect to the base 60 by a vertical axis. On the index table 50, four holder units 22 as holding means for holding a pair of master disks 46 and one slave disk 40 are arranged at regular intervals (every 90 degrees) in the rotation direction of the index table 50. Has been.

  As shown in the sectional view of FIG. 3, the holder unit 22 includes a fixed side holder 23 and a moving side holder 24 which are a pair of holder portions. The fixed-side holder 23 and the moving-side holder 24 each hold and fix the master disk 46 by adsorbing or adhering by external setup or the like, and adsorbing and holding the slave disk 40, and the slave disks 40 are in close contact with the master disks 46 and 46. It can be held in a state.

  The fixed-side holder 23 and the moving-side holder 24 have different information recorded on the fixed-side holder 23 and the moving-side holder 24 so as to correspond to the magnetic information recorded on the respective main surfaces of the slave disk 40. The master disks 46 are fixed. The set of these two master disks 46, 46 can be brought into close contact with each main surface of the slave disk 40 and sandwiched.

  The fixed side holder 23 is a circular cup-shaped member, and can fix the master disk 46 in the cup. The moving side holder 24 is a disk-shaped member and can fix the master disk 46 on the surface. The fixed side holder 23 is fixed to the apparatus main body 12. On the other hand, the moving side holder 24 is fixed to the apparatus main body 12 via a driving means (not shown), and can move so as to be able to contact and separate from the fixed side holder 23.

  With the configuration of the holder unit 22 described above, when the slave disk 40 is supplied or removed, as shown in FIG. 3, the fixed side holder 23 and the moving side holder 24 are separated by a predetermined distance. Thus, the slave disk 40 can be easily handled by the disk supply unit 26 and the disk discharge unit 34 described later.

  In the apparatus main body 12 of FIG. 1, the index table 50 is intermittently rotated by a drive motor (not shown), and is sequentially sent to each process position and stopped so that each holder unit 22 corresponds to each index position. Multiple work can be done in parallel. The index table 50 is intermittently driven so that the four holder units 22 are always arranged at predetermined four positions. That is, each holder unit 22 stops every 90-degree movement.

  Further, the apparatus main body 12 of FIG. 1 has the disk supply unit 26 on one side of the upper surface of the base 60 (left side of the front in FIG. 1) and the other side of the upper surface of the base 60 (right side of the front in FIG. 1). ) Are each provided with a disc discharge unit 34.

  The disk supply unit 26 can directly transport the slave disk 40 from the supply cassette 38 to the holder unit 22 to which the master disks 46 and 46 are attached without transferring the slave disk 40 to another chuck mechanism. Means.

  On the contrary, the disk discharge unit 34 is a disk discharge unit that can directly convey the slave disk 40 that has completed the magnetic transfer operation to the disk discharge cassette 56 without transferring it to another chuck mechanism.

  The slave disk 40 taken out from the supply cassette 38 by the disk supply unit 26 is positioned relative to the master disk 46 mounted in advance on the fixed side holder 23 of the holder unit 22. 46, the magnetic information recording surface of the master disk 46 and the magnetic information transfer surface of the slave disk 40 are held in close contact with each other. A suction groove (not shown) for sucking the vicinity of the inner diameter of the slave disk 40 is provided inside the fixed side holder 23, and the slave disk 40 is sucked and held by this suction groove.

  As shown in FIG. 2, the disk supply unit 26 includes a chuck mechanism 42 including chucks 42a and 42b, which are two pieces of holders for gripping the inner diameter of the slave disk 40, and a chuck mechanism 42 as shown in FIG. The chucks 42a, 42b are rotated so that the robots 27, 28, 29 on the XYZ axes and the slave disk 40 are rotated 180 degrees in the XZ plane. It is comprised from the rotary cylinder 44 which has.

  That is, the disk supply unit 26 rotates the chucks 42 a and 42 b holding the inner diameter of the slave disk 40 by 180 degrees by the rotary cylinder 44 to reverse the directions of the slave disk 40 and the chuck 42.

  The disc ejection unit 34 is a disc ejecting unit that receives the slave disc 40 after magnetic transfer after the holder unit 22 is opened, and directly conveys and stores the slave disc 40 to the disc ejection cassette 56.

  The disk ejection unit 34 includes a chuck mechanism 52 including chucks 52 a and 52 b that are two holders that hold the inner diameter of the slave disk 40, robots 35, 36, and 37 on the XYZ axes, and the slave disk 40. Is formed of a rotary cylinder 54 having a rotation axis in the X-axis direction for rotating the chucks 52a and 52b so as to rotate 180 degrees in the YZ plane.

  That is, the disc ejection unit 34 rotates the chucks 52a and 52b holding the inner diameter of the slave disc 40 by 180 degrees by the rotary cylinder 54, thereby reversing the directions of the slave disc 40 and the chuck 52.

  As shown in FIG. 4, a reference mark 21 </ b> A is attached in advance to the lower surface portion of the fixed side holder 23 of the holder unit 22, and recognition marks 21 </ b> B and 21 </ b> B are preliminarily attached to the chucks 42 a and 42 b of the disk supply unit 26. It is attached. The reference mark 21A and the recognition marks 21B and 21B are visually recognized by the recognition unit 30.

  The recognition unit 30 is disposed on the upper surface of the base 60 at a position close to the side surface opposite to the side surface on which the disk supply cassette 38 is provided. When the recognition unit 30 positions the slave disk 40 conveyed by the disk supply unit 26 on the master disk 46, the reference mark 21A and the recognition marks 21B and 21B attached in advance to the holder unit 22 and the disk supply unit 26, respectively. Is visually recognized by a CCD camera or the like.

  The recognition unit 30 is connected to control means 30A as positioning means. The control means 30A calculates the center of the master disk 46 from the recognized reference mark 21A, and from the recognized recognition marks 21B and 21B to the slave disk 40. The center of is calculated. The Y-axis robots 28 and 29 of the disk supply unit 26 are driven and controlled so that the centers of the master disk 46 and the slave disk 40 coincide.

  The positioned slave disk 40 is moved by the X-axis robot 27 of the disk supply unit 26 to a position in close contact with the master disk 46 held inside the fixed-side holder 23, and is sucked and held inside the fixed-side holder 23. Is done.

  At this time, the positional relationship between the reference mark 21A provided on the fixed-side holder 23 and the center position of the master disk 46 held on the fixed-side holder 23 is previously taught by the control means 30A.

  On the other hand, the relationship between the recognition marks 21B and 21B provided on the disk supply unit 26 and the center position of the slave disk 40 is such that the slave disk is on a straight line connecting the portions where the chucks 42a and 42b abut by the chucking operation of the chuck mechanism 42. When it is assumed that there are 40 centers, the relationship between the center positions and the recognition marks 21B and 21B is taught in advance to the control means 30A.

  Based on these taught positional relationships, the positional relationship between the slave disk 40 and the master disk 46 is calculated indirectly.

  The coil units 32 and 32 are in a state in which the holder unit 22 is closed and the slave disk 40 is sandwiched between master disks 46 and 46 fixed to the fixed side holder 23 and the moving side holder 24 of the holder unit 22, respectively. On the other hand, the coils are arranged on both sides of the master disks 46 and 46 and the slave disk 40 as viewed from the stacking direction. The coil units 32 and 32 apply a magnetic field having a predetermined strength for promoting the magnetic transfer action to the master disks 46 and 46 and the slave disk 40.

  Next, an inspection means for inspecting the contamination state of the surfaces of the master disks 46 and 46, which is a characteristic part of the present invention, and a contaminated portion on the surface of the master disks 46 and 46 inspected by the inspection means are selectively cleaned. The cleaning means to perform will be described.

  In FIG. 1, an inspection unit and a cleaning unit are provided on the side surface of the holder unit 22 at the disc discharge process position 86. In FIG. 1, only the CCD camera 16 that is an image pickup device and the illumination unit 17 that is a light irradiation unit among the inspection units are illustrated, and the cleaning unit is retracted and located on the opposite side of the holder unit 22. Not shown.

  5 is a perspective view showing the positional relationship between the inspection means and the holder unit 22, FIG. 6 is a front view, and FIG. 7 is a plan view. This inspection means includes a CCD camera 16 that is an image sensor, an illumination means 17, and a mirror 18. Among these, the CCD camera 16 includes a camera body 16A and a lens barrel 16B. The CCD camera 16 is connected to the control means 30A described above.

  The CCD camera 16 is supported by the support means 16C, and can be rotated by a small amount around the X axis and the Z axis according to the instruction of the control means 30A, and corresponds to the inspected parts of both the master disks 46 and 46. It can be done.

  Furthermore, the CCD camera 16 can be retracted so as not to interfere with the robots 35, 36, and 37 of the disk ejection unit 34 at the end of the inspection.

  The resolution and brightness of the lens used in the lens barrel 16B of the CCD camera 16 are important. Therefore, when a high resolution lens of 0.5 to 2 times is used as this lens, the resolution of the lens is preferably 10 μm or less, and more preferably 5 μm or less.

  The brightness of this lens is preferably larger because it detects scattered light from contamination (adhered matter) on the surfaces of the master disks 46, 46, and the F value is preferably 8 or less, more preferably F6 or less.

  In addition to the line image sensor, an area image sensor can be used as the sensor unit of the CCD camera 16. In this case, in any sensor, the detection sensitivity increases as the sensor sensitivity and the number of pixels increase. In that sense, the pixel pitch of the sensor is preferably 10 μm or less, and more preferably 5 μm or less. The number of pixels of the sensor is preferably 5000 to 8000 pixels for the line image sensor, and preferably 6 million pixel class for the area image sensor.

  When the sensor unit of the CCD camera 16 is a line image sensor, the image is captured while being rotated. However, in the case of an area image sensor, it is necessary to stop and capture an image or capture a still image with a high-intensity strobe. .

  The illuminating means 17 illuminates the master disk 46 to be inspected obliquely from among the master disks 46 and 46 held by suction by the holder unit 22. As the illumination means 17, a halogen light source can be preferably employed. In particular, when the contamination of the surfaces of the master disks 46 and 46 is a minute deposit, a metal halide light source with a large green and blue component having a wavelength of 600 nm or less can be preferably used to detect this.

  The brightness of the illumination light emitted from the illumination means 17 is also important, and is preferably at least 100,000 Lx. When the luminance of the illumination light is 100,000 Lx or more, it is possible to detect a deposit of a submicron class.

  Although one illuminating means 17 is provided, if two illuminating means 17 are provided and illumination is performed from the opposite side on the same optical axis, the luminance at the inspected portion of the master disk 46 is improved, and from one side. This makes it possible to shine an object that is difficult to reflect with this illumination, further increasing the detection sensitivity.

  As another configuration, it is also possible to employ a configuration in which a reflecting mirror is placed instead of the illuminating means on the opposite side. In this case, if it condenses with reflective mirrors, such as a concave mirror, the to-be-inspected site | part of the master disk 46 can be illuminated efficiently.

  Note that when the illumination from the illumination means 17 strikes the imaging mirror 18, it becomes a noise component such as flare. Therefore, the illumination light needs to be sufficiently narrowed by a lens or the like.

  In addition, a high-intensity laser can be used as the illumination means 17 instead of the halogen light source. In this case, a shorter wavelength such as an argon laser or a YAG second harmonic laser is preferable in terms of detection sensitivity.

  In addition, it is preferable to use S-polarized light that is parallel to the surface of the region to be inspected because the reflection of the pattern is further reduced. Polarized light has an effect of reducing pattern reflection even with ordinary illumination means, but if the brightness of the illumination means is not sufficiently increased, the luminance may decrease and the detection sensitivity may decrease. Similarly, the polarizing plate may be attached to the light receiving lens of the CCD camera 16 so as to pass only the P-polarized light generated during irregular reflection. Even in that case, it is preferable to increase the luminance of the light source as much as possible.

  The illumination means 17 is supported by a support means (not shown), and can be rotated by a small amount around the X axis and the Y axis according to instructions from the control means 30A. It can be supported. The optical axis of the illuminating means 17 is supported at an angle of 0 to 30 degrees with respect to the radial direction of the portion to be inspected on the surface of the master disk 46.

  The mirror 18 is disposed between the two master disks 46 and 46 in the holder unit 22 by support means (not shown). The mirror 18 is disposed so as to be inclined with respect to the surface of the master disk 46, and is disposed at a position where an image of the inspected portion of the master disk 46 can be imaged by the CCD camera 16 via the mirror 18.

  Both surfaces of this mirror 18 are formed into mirror surfaces, and can be rotated a little around the Z-axis by an instruction from the control means 30A, so that both of the master discs 46 and 46 can be inspected. It has become.

  Further, the mirror 18 can be retracted to the outside between the two master disks 46 and 46 inside the holder unit 22 at the end of the inspection.

  The size of the mirror 18 is preferably a sufficient size (equivalent to the lens aperture) corresponding to the lens used in the lens barrel 16B of the CCD camera 16. The mirror 18 is preferably a highly accurate surface reflecting mirror.

  The surface accuracy of the mirror 18 is preferably ¼ wavelength or less, and more preferably 1/10 wavelength or less. Note that a system that does not use the mirror 18 is more desirable as long as the opening interval of the holder unit 22 is sufficient or can be shifted one side at a time.

  With the above-described configuration of the inspection means, the surface of the master disk 46 can be inspected, including the concavo-convex pattern produced corresponding to the magnetization pattern such as the servo signal of the master disk 46. Then, the information (defect (contamination) and position information thereof) of the inspected part of the master disk 46 imaged by the CCD camera 16 is stored in the control means 30A described above.

  As the inspection means, in addition to the above-described configuration, for example, a laser beam is scanned on the surface of the master disk 46, and the reflected light is captured by a photomultiplier or a photodiode. Various known inspection methods such as an inspection method, a method of irradiating the surface of the master disk 46 with light such as halogen light, and capturing the reflected light with a CMOS line image sensor, an area image sensor, or the like can be employed.

  Even in this case, it is necessary that the optical axis of the light irradiating means be supported at an angle of 0 to 30 degrees with respect to the radial direction of the portion to be inspected on the surface of the master disk 46. It is.

  Next, the cleaning means will be described. FIG. 8 is a perspective view showing the positional relationship between the cleaning means and the holder unit 22. The cleaning means includes an air nozzle 19 and a suction nozzle 20.

  The air nozzle 19 is a cylindrical member having a small diameter at the tip, and can blow a high-pressure jet flow from an air supply source (not shown) to a portion to be cleaned of the master disk 46. That is, the air nozzle 19 can be moved between the two master disks 46, 46 inside the holder unit 22 by support means (not shown), and around the X axis and Z axis according to instructions from the control means 30A. A small amount can be rotated around the master disk 46, so that both the master disks 46 and 46 can be cleaned.

  The air nozzle 19 incorporates a filter and an ultrasonic whistle (not shown) so that clean air to which vibration is applied can be ejected.

  The suction nozzle 20 is a thin cylindrical member having a rectangular cross section, and is connected to suction means (not shown). The suction nozzle 20 can be moved to a position opposite to the air nozzle 19 between the two master disks 46 and 46 inside the holder unit 22 by a support means (not shown). The air of the generated high-pressure jet flow and foreign matter on the master disk 46 can be sucked.

  With the above configuration of the cleaning unit, the defect (contamination) on the master disk 46 is selectively (locally) according to the information (defect (contamination) and its position information) of the inspected part stored in the control unit 30A. It can be removed.

  As the cleaning means, in addition to the above-described structure, for example, dry ice fine particle spraying means, excimer laser partial irradiation means, weakly sticky cleaning roller or cleaning sheet pressing structure, cleaning cloth, etc. Various known cleaning methods can be employed, such as a wiping structure that uses wiping, and burnishing means that brings the glide head closer to the surface of the rotating master disk 46.

  Next, an operation method of the magnetic transfer apparatus configured as described above will be described. FIG. 9 is a flowchart for explaining the operation method of the magnetic transfer apparatus.

  When the operation is started, the chuck mechanism 42 (chucks 42a and 42b) of the disk supply unit 26 grips the slave disks 40 in the disk supply cassette 38 and sequentially removes them one by one (step S-10).

  The taken-out slave disk 40 is reversed in the YZ plane by the rotation of the rotary cylinder 44, and then is mastered by the X-axis robot 27 formed by the opened holder unit 22 arranged at the disk supply process position 82. The gap between the disks 46 and 46 is moved to a direction perpendicular to the opening / closing direction of the holder unit 22 and is inserted into the gap between the master disks 46 and 46 by the Y-axis robot 28 (step S-12). .

  At this time, the master discs 46 and 46 are respectively arranged in advance inside the fixed side holder 23 and the moving side holder 24 of the holder unit 22 by external setup or the like so that the center of the holder unit 22 and the center of the master disc 46 coincide. It is fixed to the position with high accuracy by suction or adhesion.

  The center of the slave disk 40 supplied between the fixed-side holder 23 and the moving-side holder 24 of the holder unit 22 is fixed to the inside of the fixed-side holder 23 by the XYZ axis robot of the disk supply unit 26. It is moved to a recognition position that substantially coincides with the center of the master disk 46 and that the gap with the master disk 46 is about 0.5 mm.

  Next, the reference mark 21A attached in advance to the lower surface of the fixed holder 23 and the recognition marks 21B and 21B attached in advance to the chuck mechanism 42 (chucks 42a and 42b) of the disk supply unit 26 are recognized by the recognition unit 30. .

  Due to this recognition, the Y− of the disk supply unit 26 is adjusted so that the center of the master disk 46 calculated from the reference mark 21A and the center of the slave disk 40 calculated from the recognition marks 21B and 21B of the chuck mechanism 42 coincide. The slave disk 40 is positioned by the Z-axis robots 28 and 29.

  Next, the slave disk 40 is moved by the X-axis robot 27 of the disk supply unit 26 to a position in close contact with the master disk 46 fixed inside the fixed side holder 23, and is sucked and fixed inside the fixed side holder 23. The

  Next, the moving side holder 24 is moved toward the fixed side holder 23 by the robot 70, and both sides of the slave disk 40 are sandwiched between the two master disks 46 and 46. In this way, the both sides of the slave disk 40 are sandwiched with the two master disks 46, 46 in contact (step S-14).

  Next, the index table 50 is rotated by 90 degrees (step S-16), and the holder unit 22 is positioned at the magnetic transfer process position 84 of the next process. The coil units 32 and 32 are moved to both sides of the holder unit 22 (step S-18), and a magnetic field is applied from both sides while rotating the holder unit 22 (step S-20). As a result, the magnetic information patterns of the master disks 46 and 46 are magnetically transferred onto both sides of the slave disk 40.

  After the magnetic transfer, the coil units 32 and 32 are retracted to the initial position (step S-22), the index table 50 is rotated by 90 degrees, and the holder unit 22 is positioned at the next disk ejection process position 86 (step). S-24).

  Next, the moving side holder 24 is moved away from the fixed side holder 23 (step S-26). At this time, the magnetically transferred slave disk 40 is attracted to the inside of the fixed side holder 23 as in the supply.

  Next, the mirror 18 of the inspection means is moved between the two master disks 46 and 46 in the holder unit 22, and the CCD camera 16 and the illumination means 17 are adjusted to appropriate positions, and the attached matter on the master disk 46. An inspection is performed, and information on the region to be inspected (defect (contamination) and its position information) is stored in the control means 30A (step S-28).

  If the control means 30A determines good (OK) as a result of the deposit inspection, the process proceeds to the next step (step S-30) of the steady flow, and if the control means 30A determines that the control means 30A is defective (NG), The process proceeds to the cleaning process (master cleaning) by the cleaning means (step S-40).

  In the cleaning process (step S-40), the mirror 18 of the inspection means is retracted from between the two master disks 46, 46 inside the holder unit 22, and the air nozzle 19 and the suction nozzle 20 are two inside the holder unit 22. Are moved to a predetermined position between the master disks 46 and 46.

  Then, clean air to which vibration is applied is ejected from the air nozzle 19 to remove the foreign matter on the master disk 46, and the high-pressure jet stream air blown by the suction nozzle 20 and the foreign matter on the master disk 46 are removed. Suction. Thereby, the defect (contamination) on the master disk 46 is selectively (locally) removed.

  Next, the mirror 18 of the inspection means is moved between the two master disks 46 and 46 in the holder unit 22, and the CCD camera 16 and the illumination means 17 are adjusted to appropriate positions, and the attached matter on the master disk 46. Is re-inspected (step S-44).

  If the control means 30A determines that the control means 30A is good (OK) as a result of the re-examination, the process proceeds to the next step (step S-30) of the steady flow, and the control means 30A determines that the control means 30A is defective (NG) (for example, When an error in the same part is detected continuously, the automatic operation is stopped, the contaminated master disk 46 is replaced with a new master disk 46, and the contaminated master disk 46 is cleaned off-line. (Step S-46).

  When off-line cleaning of the contaminated master disk 46 is performed, defect (attachment) information may be output as position information from the inspection apparatus to the off-line cleaner via a LAN or the like. Also, positioning holes and marks may be provided in advance on the master disk 46, and the online position and offline position may be matched based on the holes.

  As the off-line cleaning of the master disk 46, liquid cleaning with megasonic vibration by an ultrasonic cleaning head, ultrasonic vibration cleaning in the liquid or air of a cleaning tank by an ultrasonic vibration head, electrolytic degreasing cleaning, For example, gas blowing with sonic vibration, glide cleaning with a glide head having a width larger than the track width, ultrasonic cleaning after glide cleaning, incineration cleaning with excimer laser irradiation, plasma cleaning, and the like can be used.

  Note that it is preferable to perform glide cleaning with the flying height of the glide head being 40 nm or less. Further, the entire cleaning of the master disk 46 as described above may be performed before a new master disk 46 is set in the magnetic transfer apparatus 10.

  In the steady flow, in the next step (step S-30), the chuck 52 of the disk ejection unit 34 enters between the fixed side holder 23 and the moving side holder 24 and grips the inner diameter of the slave disk 40. Then, the suction of the slave disk 40 of the fixed side holder 23 is released, and the chuck 52 of the disk discharge unit 34 is moved by the X-axis robot 35 of the disk discharge unit 34, whereby the slave disk 40 is moved to the master disk 46 of the fixed side holder 23. Peel from.

  Next, in a state where the slave disk 40 is gripped by the chuck 52 of the disk ejection unit 34, the Y-axis robot 36 is retracted from the opened gap of the holder unit 22 in the Y-axis direction. Then, the rotary cylinder 54 is rotated 180 degrees along a circular path passing through the outside of the apparatus in the YZ plane, and the vertical direction including the chuck 52 is reversed.

  Next, the slave disk 40 and the chuck 52 are moved onto the disk discharge cassette 56 by the XYZ robots 35, 36, and 37 of the disk discharge unit 34, and the slave disks 40 are sequentially stored in the disk discharge cassette 56 one by one. To do.

  The series of operations described above can process each process in parallel by positioning the holder unit 22 at each process position while intermittently rotating the index table 50 sequentially.

  The embodiments of the magnetic transfer method, apparatus, and master disk inspection method according to the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various aspects can be adopted.

  For example, in the above-described embodiment, after the new master disk 46 is set, dust having a weak adhesive force may adhere during storage or setting. Therefore, before the transfer, relatively weak entire surface cleaning such as high-pressure air is performed. And better to do.

  Thereafter, in step S-28, an initial inspection is performed, and initial defects that do not affect the quality, such as pattern reflections that are not defects and minute dents outside the pattern, are registered. Based on this data, only the increase from the initial stage of inspection after transfer is targeted, and excessive detection is suppressed. As a result, the pattern can also be used as a base for floating binarization, and the excessive inspection can be further suppressed.

  In the above embodiment, the deposit inspection of the master disk 46 and the discharge of the slave disk 40 are performed at the same process position (disk discharge process position 86 in FIG. 1). You may go.

  Further, in the above embodiment, transfer of a magnetic disk has been described. However, the present invention can be suitably applied not only to transfer of a magnetic disk but also to various media such as an optical disk (including a magneto-optical disk).

  Further, the configuration of the magnetic transfer apparatus 10 is not limited to the rotary index system of the above-described embodiment, and various forms such as an inline index system can be adopted.

  Using the magnetic transfer apparatus 10, the deposit on the master disk 46 was inspected. At this time, as an embodiment of the present invention, the inspection means (CCD camera 16, illumination means 17 and mirror 18) shown in FIGS. A 250 W metal halide light source, a fiber, a condenser lens, and an infrared cut filter were used as the illumination means 17.

  The optical axis of the illumination means 17 was adjusted to make an angle of 3 degrees with respect to the radial direction of the inspected portion of the surface of the master disk 46. More specifically, the tilt angle with respect to the surface (plane) of the disk was adjusted to 3 degrees, and the tilt angle with respect to the radius of the disk surface (plane) was adjusted to 0 degrees.

  As a comparative example, the inspection means (CCD camera 16 and mirror 18) shown in FIGS. However, in place of the illumination means 17, a 150 W halogen lamp, a fiber, a condenser lens, and an infrared cut filter were used. Then, the optical axis of this light source was adjusted so as to make an angle of 45 degrees with respect to the radial direction in the portion to be inspected on the surface of the master disk 46.

  FIG. 10 is an example of an image captured by the CCD camera 16. Among these, (A) is a result of a comparative example, (B) is a result of an Example.

  In FIG. 10A, since the protruding magnetic layer pattern shows a high reflection in a line shape, it can be seen that the CCD charge leaks to the periphery of the pattern.

  On the other hand, in FIG. 10B, it can be seen that the luminance of the protrusion-like magnetic layer pattern is sufficiently lowered without changing the luminance of the deposit.

  FIG. 11 is an image after the image of FIG. 10 is binarized. (A) and (B) in FIG. 11 correspond to (A) and (B) in FIG. 10, respectively.

  In the comparative example of FIG. 11A, the charge of the CCD leaks to the periphery of the pattern even after binarization. Therefore, in the comparative example, the pattern portion must be masked, and there is a risk that many deposits may be missed.

  On the other hand, in the example of FIG. 11B, it can be read that only the adhering matter is detected after binarization.

  12A and 12B are diagrams showing the master disk 46 used for the deposit inspection, wherein FIG. 12A shows a measurement site, and FIG. 12B is an enlarged view in a circle of FIG.

The perspective view which fractures | ruptures and shows a part of magnetic transfer apparatus based on this invention A perspective view showing a state in which a slave disk is put in and out of a disk cassette. Sectional view showing the configuration of the holder unit The perspective view which shows the alignment state of a master disk and a slave disk The perspective view which shows the positional relationship of an inspection means and a holder unit Same front view Same top view The perspective view which shows the positional relationship of a cleaning means and a holder unit Flowchart explaining operation method of magnetic transfer apparatus Example of images taken with a CCD camera The image after binarizing the image of FIG. The figure which shows the master disk used for adhesion inspection

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Magnetic transfer apparatus, 12 ... Apparatus main body, 14 ... Clean unit, 16 ... CCD camera, 17 ... Illuminating means, 18 ... Mirror, 19 ... Air nozzle, 20 ... Suction nozzle, 22 ... Holder unit (holding means), 23 ... Fixed side holder, 24 ... Moving side holder, 26 ... Disc supply unit, 32 ... Coil unit, 34 ... Disc discharge unit, 38 ... Disc supply cassette, 40 ... Slave disc (disc to be transferred), 46 ... Master disc, 56 ... Disc cassette, 70 ... Robot (drive means)

Claims (6)

Disk holding means for holding a master disk having a large number of protruding patterns formed on the surface thereof by a holder portion;
Transfer means for transferring the pattern of the master disk to the transfer disk;
The light irradiation means irradiates the irradiation light so that the optical axis of the irradiation light forms an angle of 0 to 30 degrees with respect to the radial direction in the inspected portion of the surface of the master disk, and reflects the reflected light of the irradiated light. Inspection means for inspecting the contamination state of the surface of the master disk by imaging with an image sensor;
A transfer apparatus comprising: Disk holding means for holding a master disk having a plurality of protruding magnetic layer patterns formed on the surface thereof by a holder portion;
A magnetic field applying means for applying a magnetic field to the holder part to transfer the magnetic pattern of the master disk to a disk for transfer;
The light irradiation means irradiates the irradiation light so that the optical axis of the irradiation light forms an angle of 0 to 30 degrees with respect to the radial direction in the inspected portion of the surface of the master disk, and reflects the reflected light of the irradiated light. Inspection means for inspecting the contamination state of the surface of the master disk by imaging with an image sensor;
A transfer apparatus comprising:   The transfer apparatus according to claim 1, further comprising a cleaning unit that selectively cleans a contaminated portion on the surface of the master disk inspected by the inspection unit. Supply means for supplying a transfer target disk so as to face the master disk held by the holder part;
The transfer apparatus according to claim 1, further comprising a driving unit that operates the holding unit to press the master disk against the transfer target disk. A supplying step of supplying a transfer-receiving disk so as to face a master disk having a large number of protruding magnetic layer patterns formed on the surface of the holder and held by the holder unit;
A pressure-contacting step of pressing and holding the master disk to the supplied disk for transfer;
A transfer step of applying a magnetic field to the holder part to transfer the magnetic pattern on the master disk to the disk to be transferred;
The light irradiation means irradiates the irradiation light so that the optical axis of the irradiation light forms an angle of 0 to 30 degrees with respect to the radial direction in the inspected portion of the surface of the master disk, and reflects the reflected light of the irradiated light. An inspection step of inspecting the contamination state of the surface of the master disk by imaging with an image sensor;
A transfer method comprising: A master used for supplying a disk to be transferred so as to face a master disk having a large number of protruding magnetic layer patterns formed on the surface and transferring the pattern of the master disk to the disk to be transferred A method for inspecting a master disk for inspecting a contamination state of a disk surface,
The light irradiation means irradiates the irradiation light so that the optical axis of the irradiation light forms an angle of 0 to 30 degrees with respect to the radial direction in the inspected portion of the surface of the master disk, and reflects the reflected light of the irradiated light. A method for inspecting a master disk, characterized in that the surface of the master disk is inspected by imaging with an image sensor.

Images