KR100716528B1 - Disk drive apparatus, servo control circuit, method of manufacturing recording medium, magnetic recording medium, and method of checking recording medium - Google Patents

Abstract

A disk drive device that determines the position of the head by using servo information recorded on a recording medium, wherein a defect obtained in the K servo information by inspecting a transferred slave medium or a master medium by using a master medium recording K group servo information is detected. A servo gate generator for generating a servo gate corresponding to a recording position of a group of non-servo information pairs or a servo information pair having the best servo characteristics, and a servo controller for servo control corresponding to the servo gate generated by the servo gate generator. do.

Description

DISK DRIVE APPARATUS, SERVO CONTROL CIRCUIT, METHOD OF MANUFACTURING RECORDING MEDIUM, MAGNETIC RECORDING MEDIUM, AND METHOD OF CHECKING RECORDING MEDIUM}

The present invention relates to a disk drive apparatus for determining the position of a head using servo information recorded on a recording medium, a servo control circuit, and a method of manufacturing a recording medium for use in manufacturing the disk apparatus, and a magnetic recording medium and a media inspection. In particular, the present invention relates to a disk drive device, a servo control circuit, and a disk device, which can improve the quality of servo information used for servo control, thereby preventing performance degradation due to bad servo information and inability to follow tracking. A method for manufacturing a recording medium to be used, a magnetic recording medium and a method for inspecting a medium.

In recent years, the capacity of magnetic disk devices, which are used as storage devices for computers and AV (Audio Visual) devices, has been increasing at an phenomenal speed. This increase in capacity is realized by an increase in the data recording density of the magnetic disk. As the data recording density of the magnetic disk increases, the recording density of the servo information also increases.

Here, the servo information is information which is recorded in advance on the magnetic disk of the magnetic disk apparatus, which is read by the magnetic head at regular time intervals and used for positioning the magnetic head.

After the magnetic disk is incorporated in the magnetic disk device, this servo information is recorded on the track of the magnetic disk by the same number of sectors at regular intervals using a dedicated device called a servo writer. As the recording density increases, the recording time of the servo information increases, which causes a decrease in the productivity of the magnetic disk device.

Therefore, in order to cope with an increase in the recording time of servo information, a magnetic transfer technique has been developed in which servo information is collectively recorded on a magnetic disk using a device called a magnetic transfer device.

In the self-transfer, the recording time of the servo information can be shortened by transferring the servo information collectively by applying direct current magnetization in a state where the master medium in which the servo information has been recorded in advance and the slave medium in which the servo information is recorded are brought into close contact. See Japanese Patent Laid-Open No. 4-251440 (page 2-3, Fig. 2) (Patent Document 1).

In addition, a technique for detecting a transfer failure before and after self-transfer has been developed, such as a foreign material inspection for checking whether a foreign substance is loaded on a slave medium or a read write test for recording and reading a signal on a slave medium [eg, a Japanese patent]. See Publication No. 2002-25054 (Patent Document 2)].

However, in the conventional self-transfer method, if there is a drop in the servo information after the transfer, the sector corresponding to the servo information becomes unusable, and the performance deterioration due to the process of reading out the unusable sector and the following control. There is a problem that disabling occurs.

Disclosure of Invention The present invention has been made to solve the problems caused by the above-described prior art, and a disk drive apparatus capable of improving the quality of servo information used for servo control and preventing performance degradation and inability to follow tracking caused by bad servo information; It is an object of the present invention to provide a servo control circuit, a method of manufacturing a recording medium for use in the manufacture of a disk device, and a method of inspecting a magnetic recording medium and a medium.

In order to solve the above problems and achieve the object, the present invention is a disk drive device for determining the position of the head by using the servo information recorded on the recording medium, which is selected from a plurality of sets of servo information recorded on the recording medium. And servo control means for servo control using the servo information of the pair.

According to the present invention, since the servo control is performed using the selected servo information from the plurality of sets of servo information recorded on the recording medium, the quality of the servo information used for the servo control is improved, and the performance degradation caused by the poor servo information and It can prevent following control.

In addition, the present invention is a servo control circuit, comprising: a used servo information identifier recording circuit which records an identifier of a group of servo information to be used for servo control among a plurality of sets of servo information recorded on a recording medium, and recorded in the used servo information identifier recording circuit. A servo information selection circuit for selecting servo information of a set to be used among the plurality of sets of servo information using an identifier, and a position control circuit for controlling the position of the head using the servo information selected by the servo information selection circuit. It is done.

According to the present invention, a group identifier of a group of servo information to be used for servo control is recorded from a plurality of sets of servo information recorded on a recording medium, and the selected servo information is selected from among a plurality of sets of servo information using the recorded identifier. Since the position of the head is controlled to be used, the quality of the servo information used for the servo control can be improved to prevent the performance deterioration and the following control failure due to the poor servo information.

In addition, the present invention provides a method of manufacturing a recording medium, comprising: a used servo information determination step of determining a group of servo information to be used among a plurality of sets of servo information included in a master medium, and transferring the plurality of sets of servos by using the master medium; And a slave medium creation step of creating a slave medium on which information is recorded.

According to the present invention, since a group of servo information to be used is determined from among a plurality of sets of servo information of the master medium, the master medium is transferred, and a slave medium on which a plurality of sets of servo information is recorded is used for servo control. By improving the quality of the servo information, it is possible to prevent the performance deterioration and the following control failure due to the poor servo information.

In addition, the present invention provides a method for manufacturing a recording medium, comprising: a slave medium creating step of transferring a master medium having a plurality of sets of servo information to create a slave medium on which the plurality of sets of servo information is recorded, and the plurality of sets of servos. And a use servo information determination step of determining a set of servo information to be used from among the information.

According to the present invention, the servo control is performed by transferring a master medium having a plurality of sets of servo information, creating a slave medium on which a plurality of sets of servo information is recorded, and determining a set of servo information to be used among the sets of servo information. The quality of the servo information to be used can be improved to prevent the performance deterioration and the following control failure due to the poor servo information.

Also, in the present invention, as a magnetic recording medium, a plurality of sets of servo information are recorded, and the servo information of a set selected based on the inspection result of the recorded plurality of sets of servo information is used for positioning of the magnetic head by the magnetic disk drive apparatus. It is characterized by.

According to the present invention, a plurality of sets of servo information are recorded, and the servo information of a set selected based on the inspection result of the recorded sets of servo information is used by the magnetic disk drive apparatus for positioning the magnetic head. The quality of the servo information used can be improved to prevent performance deterioration and inability to follow tracking due to bad servo information.

The present invention also provides a method for inspecting a medium, comprising: detecting a defect of a medium having a plurality of sets of servo information, and selecting a set of servo information to be used among the plurality of sets of servo information based on the defect position. It is characterized by.

According to the present invention, since a defect of a medium having a plurality of sets of servo information is detected and a group of servo information to be used is selected from among a plurality of sets of servo information based on the defect position, the quality of the servo information used for servo control is improved. Therefore, it is possible to prevent performance deterioration due to bad servo information and inability to follow tracking.

1 is an explanatory diagram for illustrating a concept of a plurality of sets of servo information according to the present embodiment.

2 is a functional block diagram showing the configuration of the servo information analyzing apparatus and the magnetic disk drive apparatus according to the present embodiment.

3 is an explanatory diagram for explaining a servo gate generated by the servo gate generator.

4 is a flowchart showing a self-transcription procedure according to the present embodiment, and FIG. 5 is an explanatory diagram for explaining a master pattern generation process.

FIG. 6 is a flowchart showing the processing procedure of the used servo information determining unit shown in FIG.

FIG. 7 is a flowchart showing a self-transfer procedure in the case of determining a set of used servo information based on the servo characteristics of a slave medium.

8 is a flowchart showing the processing procedure of the used servo information determination processing based on the servo characteristics.

9 is an explanatory diagram for explaining the case where servo information of a different group is used according to a radial position.

10 is an explanatory diagram for explaining a magnetic disk drive apparatus of the same lot.

EMBODIMENT OF THE INVENTION Hereinafter, with reference to an accompanying drawing, preferred embodiment of the disk drive apparatus, the servo control circuit, the manufacturing method of a recording medium, the magnetic recording medium, and the inspection method of a medium which concern on this invention is described in detail.

First, the concept of the plurality of sets of servo information according to the present embodiment will be described. 1 is an explanatory diagram for illustrating a concept of a plurality of sets of servo information according to the present embodiment. As shown in Fig. 1A, in the conventional self-transfer, servo information equal to the number of sectors is transferred to the slave medium.

In contrast, as shown in FIG. 1B, in the magnetic transfer according to the present embodiment, the master medium has a plurality of sets of servo information, and the plurality of sets of servo information are transferred to the slave medium. That is, K pieces of servo information having group numbers 1 to K are transferred to each sector of the slave medium.

The magnetic disk drive apparatus selects and uses a group of servo information without defects in all sectors of these K groups or a group of servo information having the best servo characteristics. Therefore, as shown in Fig. 1C, the number of servo information after the group number of the servo information to be used is selected is equal to the number of sectors as in the conventional servo information.

Thus, in this embodiment, K group servo information is created on a master medium, and the slave medium which has K group servo information is created using this master medium. Further, the magnetic disk drive apparatus can prevent performance deterioration due to bad servo information and inability to follow tracking by using servo information of a group without defects or servo information of a group having the best servo characteristics among the group K servo information.

Next, the configuration of the servo information analyzing apparatus and the magnetic disk drive apparatus according to the present embodiment will be described. Here, the servo information analyzing apparatus is a device which detects a defect of a master medium or a slave medium and determines the group number of the servo information to be used by the magnetic disk drive device from the K group servo information based on the detected defect position.

2 is a functional block diagram showing the configuration of the servo information analyzing apparatus and the magnetic disk drive apparatus according to the present embodiment. As shown in FIG. 2, the servo information analyzing apparatus 100 includes a defect position detecting unit 110, a defect position storing unit 120, a used servo information determining unit 130, and a ROM recording unit 140. . In addition, the magnetic disk drive apparatus 200 includes a drive ROM 210, a servo gate generator 220, and a servo controller 230.

The defect position detection unit 110 is a sensor for detecting defects and dusts of the master medium or the slave medium, and detects defects and dusts at all places where the K group servo information is recorded.

The defect position storage unit 120 is a storage unit that stores defect and dust position information of a master medium or a slave medium detected by the defect position detection unit 110 and records the position stored in the defect position storage unit 120. The servo information is bad.

The use servo information determination unit 130 is a processing unit that determines the group number of the servo information on which the defective servo information does not exist based on the defect and dust position information stored in the defect position storage unit 120. The use servo information determination unit 130 determines the group number of the servo information for which the defective servo information does not exist from the K group servo information, so that the magnetic disk drive device 200 can use the servo information without omission. .

The ROM recording unit 140 is a processing unit for recording the set number determined by the used servo information determining unit 130 in the drive ROM 210. The ROM recording unit 140 records the set number in the drive ROM 210, thereby providing a servo. The magnetic disk drive apparatus 200 can use the analysis result of the information analysis apparatus 100.

The drive ROM 210 is a storage unit that stores a set number determined by the use servo information determination unit 130. The drive ROM 210 is inserted into the magnetic disk drive device 200 and used. On the other hand, in this case, the set number determined by the used servo information determining unit 130 is stored in the drive ROM 210 so that the magnetic disk drive device 200 can use it. Alternatively, a drive jumper pin may be used instead of the drive ROM 210. have.

The servo gate generator 220 recognizes the servo information of the group number stored in the drive ROM 210 by the reproduction signal from the slave medium, and generates a gate at equal intervals corresponding to the recording position of the servo information to be used. Signal generator.

3 is an explanatory diagram for describing a servo gate generated by the servo gate generator 220. As shown in Fig. 3, the servo gate generator 220, for example, when using servo information of " Tank No. 2 " at equal intervals for the servo gate corresponding to the position where the second servo information is recorded. Occurs.

The servo controller 230 is a processor that controls the servo in response to the servo gate generated by the servo gate generator 220. By performing the servo control in response to the servo gate, the servo controller 230 can perform servo control using only the servo information of the set number determined by the servo information analyzing apparatus 100.

Next, the self-transfer procedure according to the present embodiment will be described. 4 is a flowchart showing a self-transfer sequence according to the present embodiment. As shown in Fig. 4, in this self-transfer, a master medium having K group servo information is created (step S401).

On the other hand, as shown in Fig. 5, the preparation of the master medium includes (a) applying a resist to the master substrate, (b) exposing and developing, (c) etching, (d) film production, and (e) removing the resist, (f) ) Can be prepared in the same order as the conventional master media in the order of polishing. However, the pattern generated on the master substrate is K times as conventional.

Then, the defect position detecting unit 110 of the servo information analyzing apparatus 100 detects the defect position of the master medium (step S402), and uses the set of the used servo information based on the detected defect position. Is determined (step S403), and the group number is recorded by the ROM recording unit 140 in the drive ROM 210 (step S404). In addition, the created master medium is self-transferred to the slave medium (step S405).

In this manner, in this self-transfer, a master medium having K group servo information is created, and a group of defect-free servo information is found among the K group servo information created, and the group number of a group without defect is sent to the drive ROM 210. By writing, the magnetic disk drive apparatus 200 incorporating the drive ROM 210 can select the set of servo information without defect and perform servo control.

Next, the processing of the used servo information determination unit 130 shown in FIG. 2 will be described. FIG. 6 is a flowchart showing the processing procedure of the used servo information determining unit 130 shown in FIG. On the other hand, the processing of the used servo information determining unit 130 corresponds to the processing of step S403 in the self-transfer procedure shown in FIG.

As shown in Fig. 6, the use servo information determination unit 130 initializes the group number k to "1" (step S601), and checks the defect of the servo information of the group number k for all sectors (step) S602), it is determined whether there is a defect (step S603).

If there is no defect, the group number of the servo information to be used is determined as k (step S604). On the other hand, if there is a defect, it is determined whether all the servo information of the K group has been examined (step S605), and if not all the servo information of the K group has been examined, "1" is added to k (step S606), and the step is performed. Returning to S602, the servo information of the next group number is checked.

In addition, when all the servo information of the K group is examined, since there is no pair of servo information without a defect, a defect display is made (step S607) and a process is complete | finished.

On the other hand, here, the case of self-transferring to the slave medium after detecting the defect position of the master medium will be described, but the defect position of the master medium can be detected after the self-transferring to the slave medium. In addition, instead of the master medium, a slave medium may be used to detect a defective position to determine a set of used servo information.

In addition, instead of the defective position of the slave medium, the signal of the slave medium may be reproduced to measure the detection or the servo characteristic of the servo information, and the pair of the used servo information may be determined based on the detection result of the servo information or the measurement result of the servo characteristic. have.

Therefore, the self-transfer procedure in the case of determining the set of the used servo information based on the servo characteristics of the slave medium will be described. FIG. 7 is a flowchart showing a self-transfer procedure in the case of determining a set of used servo information based on the servo characteristics of a slave medium. As shown in Fig. 7, in this self-transfer, a master medium having a group of servo information is created (step S701).

Then, the created master medium is self-transferred to the slave medium (step S702), after which the signal of the slave medium is reproduced to measure servo characteristics (step S703). Then, the set of servo information having the best servo characteristic is determined as the set of servo information (step S704), and the group number of the determined set of servo information is recorded in the drive ROM 210 (step S705).

In this way, a slave medium is created by self-transfer from a master medium having K group servo information, the servo information of the created slave medium is reproduced, and the servo characteristic is measured, and the servo information set using the best servo information is used. By using the above, the magnetic disk drive apparatus 200 can perform servo control using servo information excellent in servo characteristics.

Next, the use servo information determination processing based on the servo characteristics will be described. 8 is a flowchart showing the processing procedure of the used servo information determination processing based on the servo characteristics. On the other hand, the use servo information determination process based on this servo characteristic corresponds to the process of step S704 of the self-transfer procedure shown in FIG.

As shown in Fig. 8, this used servo information determination process first initializes k and Better to " 1 " (step S801). Here, k stores the group number of the servo information under investigation, and Better stores the group number of the servo information with the highest servo characteristics among the examined servo information.

And "1" is added to k (step S802), and it is determined whether the servo characteristic of group number k is better than the servo characteristic of group number Better (step S803), and when it is favorable, it is set to Better = k (step S804). . That is, the group number of the servo information excellent in the servo characteristic among the investigated servo information is set to k.

Then, it is determined whether or not the superiority of the servo characteristic is compared with respect to all of the servo information of the group K (step S805). Compare the servo characteristics of the group number to the servo characteristics of the group number Better. Further, when the servo characteristics are compared with respect to all of the servo information of the group K, Better is determined as the number of the used servo information (step S806).

As described above, in the present embodiment, the self-transferred to the slave medium using the master medium recording the servo information of the K group, and the servo information of the servo information of the K group without the defects or the servo characteristics having the highest servo characteristics, Determine Joe. Since the servo gate generator 220 of the magnetic disk drive apparatus 200 generates a servo gate corresponding to the determined position of the servo information of the set, the servo controller 230 causes the servo control to correspond to the servo gate. Therefore, it is possible to prevent the performance degradation due to the poor servo information and the following control failure.

In the present embodiment, the case where the same set of servo information is used for all the tracks of the slave medium will be described. However, the present invention is not limited to this. The same can be applied.

9 is an explanatory diagram for explaining the case where servo information of a different group is used according to a radial position. As shown in Fig. 9, for example, three tracks on the slave medium can be classified according to their radial positions, and different sets of servo information can be used in each classification. In this case, the drive ROM stores the set number of the used servo information for each classification, and the servo gate generator generates different servo gates for each classification.

By the way, magnetic disk drive apparatuses using slave media created from the same master medium constitute the same lot. 10 is an explanatory diagram for explaining a magnetic disk drive apparatus of the same lot.

As shown in Fig. 10, the master medium " 001 " and slave media " 001-0001 ", " 001-0002 " , A magnetic disk drive device using "001-XXXX" constitutes the same lot.

In self-transfer, all slave media created from the same master medium have the same defects or servo characteristics. Thus, by examining the master medium "001" and determining the group number of the used servo information, the slave mediums "001-0001", "001-0002",... , All magnetic disk drive devices using "001-XXXX" can use servo information of the same group number.

Further, by examining one slave medium, for example, "001-0001", and determining the group number of the used servo information, the slave medium "001-0002" and "001-0003" created using the same master medium "001". ... , All magnetic disk drive devices using "001-XXXX" can use servo information of the same group number.

As described above, according to the present invention, since servo control is performed by using the servo information of the selected group among the plurality of sets of servo information recorded on the recording medium, the quality of the servo information used for the servo control is improved, and the The effect which can prevent the performance deterioration and following control which cannot be followed is exhibited.

According to the present invention, the group identifier of the servo information to be used for the servo control is recorded from the plurality of sets of servo information recorded on the recording medium, and the servo information of the pair to be used is selected from the plurality of sets of servo information by using the recorded identifier. Since the position of the head is controlled by using the information, the quality of the servo information used for the servo control can be improved, thereby exhibiting the effect of preventing the performance deterioration and the following control failure due to the poor servo information.

In addition, according to the present invention, since the set of servo information to be used is determined among the plurality of sets of servo information of the master medium, the master medium is transferred, and the slave medium on which the plurality of sets of servo information is recorded is created. The quality of the servo information to be used is improved, and the performance deterioration and the following control failure due to the poor servo information can be prevented.

In addition, according to the present invention, since a slave medium on which a plurality of sets of servo information is recorded is transferred by using a master medium having a plurality of sets of servo information, a set of servo information to be used among the plurality of sets of servo information is determined. The quality of the servo information used for servo control is improved, and the effect of being able to prevent the performance deterioration and the inability to follow tracking resulting from bad servo information is exhibited.

Further, according to the present invention, since the servo information is recorded in a plurality of sets, and the servo information of the selected group based on the recorded result of the inspection of the recorded plurality of sets of servo information is used for positioning of the magnetic head by the magnetic disk drive apparatus, the servo The quality of the servo information used for the control can be improved, and the performance deterioration and the inability to follow the control caused by the poor servo information can be prevented.

In addition, according to the present invention, since a defect of a medium having a plurality of sets of servo information is detected and a group of servo information to be used is selected from among a plurality of sets of servo information based on the defect position, the quality of the servo information to be used for servo control is improved. This improves the performance and prevents performance deterioration and tracking control failure due to poor servo information.

As described above, the disk drive apparatus, the servo control circuit, the manufacturing method of the recording medium, the magnetic recording medium, and the inspection method of the medium according to the present invention include a disk device for determining the position of the head using servo information recorded on the recording medium; It is suitable for its production.

Claims (11)

A disk drive apparatus for determining a position of a head by using servo information recorded on a recording medium, And servo control means for performing servo control by using the servo information of the selected group among the plurality of sets of servo information recorded on the recording medium, By the circle having a predetermined radius from the center of the recording medium, the recording medium is classified into a plurality of blocks, And the servo control means selects different sets of servo information according to the respective blocks. The disk drive apparatus according to claim 1, wherein the servo control means selects the servo information of a pair to be used by generating a servo gate. delete A used servo information identifier recording circuit which records an identifier of a group of servo information to be used for servo control among a plurality of sets of servo information recorded on a recording medium; A servo information selection circuit for selecting servo information of a set to be used from among the plurality of sets of servo information by using an identifier recorded in the used servo information identifier recording circuit; A position control circuit for controlling the position of the head by using the servo information selected by the servo information selecting circuit; By the circle having a predetermined radius from the center of the recording medium, the recording medium is classified into a plurality of blocks, And the use servo information identifier recording circuit records different sets of identifiers according to the respective blocks. delete A use servo information determination step of determining a set of servo information to be used from among a plurality of sets of servo information of the master medium; A slave medium creation step of transferring using the master medium to create a slave medium on which the plurality of sets of servo information are recorded; and A classification step of classifying the slave medium into a plurality of blocks by a circle having a predetermined radius from the center of the slave medium, And the use server information determining step includes determining a different pair according to each of the blocks. A slave medium creation step of transferring using a master medium having a plurality of sets of servo information to create a slave medium on which the plurality of sets of servo information is recorded; A classification step of classifying the slave medium into a plurality of blocks by a circle having a predetermined radius from the center of the slave medium; A use servo information determination step of determining a set of servo information to be used among the plurality of sets of servo information; And wherein the use servo information determination step determines a different pair according to each of the blocks. In a magnetic recording medium in which a plurality of sets of servo information are recorded, and servo information of a set selected on the basis of inspection results of the recorded plurality of sets of servo information is used for positioning of the magnetic head by the magnetic disk drive apparatus, By a circle having a predetermined radius from the center of the magnetic recording medium, the magnetic recording medium is classified into a plurality of blocks, And the selected set is different according to the respective blocks of the magnetic recording medium. Detecting a defect of a medium having a plurality of sets of servo information; A classification step of classifying the medium into a plurality of blocks by a circle having a predetermined radius from the center of the medium; Selecting a group of servo information to be used from among the plurality of sets of servo information based on a defect position; Wherein said selecting step selects a different pair according to said each block. A disk drive apparatus for positioning a head using servo information recorded on a recording medium, And servo control means for performing servo control by using the servo information of the selected group among the plurality of sets of servo information recorded on the recording medium, And the selected group is a group having the best servo characteristics among the groups without defects among the plurality of sets of servo information. A used servo information identifier recording circuit which records an identifier of a group of servo information used for servo control among a plurality of sets of servo information recorded on a recording medium; A servo information selection circuit for selecting servo information of a set to be used among the plurality of sets of servo information by using an identifier recorded in the used servo information identifier recording circuit; A position control circuit for controlling the position of the head by using the servo information selected by the servo information selecting circuit; And a group of servo information recorded in the used servo information identifier recording circuit is a group having the best servo characteristics among the groups without defects among the plurality of sets of servo information.

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