JP2008181598A - Magnetic head and manufacturing method of magnetic head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic head capable of performing a satisfied DC erasing and a servo signal recording, as a magnetic head used for a magnetic recording medium having a data signal recording section and a servo signal recording section on a magnetic layer. <P>SOLUTION: A DC erasing magnetic head Ha which has a metallic magnetic film 4a and a gap section 4c formed on a surface of a core hemi-body 5a and performs the DC erasing to the servo signal recording section, and a servo signal recording magnetic head Hb which has a metallic magnetic layer film 4b and a gap 4d formed on a surface of a core hemi-body 5b and records the servo signal on a signal recording area of the servo signal recording section by a magnetic field in the direction opposite to the DC erasing, are integrated through non-magnetic materials 7a, 7b, so that formation surfaces of the metallic magnetic films 4a, 4b are formed in the same planer shape. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a magnetic head for performing servo signal recording by a magnetic field in the direction opposite to the direct current erasure after performing direct current erasure on a servo band portion of a running recording medium, and a method of manufacturing the magnetic head. It is.

  For example, as the capacity and transfer rate of data to be recorded on a recording medium (magnetic tape) such as a computer backup device increases, the recording / reproducing head must trace a predetermined track at high speed and accurately. Further, the recording / reproducing head needs to move between tracks at a high speed and instantly move to a specific position of a specific track.

  As a method of stabilizing this operation, a servo signal is written in advance on a magnetic tape as shown in Patent Document 1 below, and the position on the magnetic tape is detected based on the signal of the servo dedicated read head that has read the servo signal, and recording is performed. There is a method of running the reproducing head stably.

  If the servo signal output is low, the position of the recording / reproducing head cannot be properly controlled, and if it is severe, the servo-dedicated reproducing head may lose sight of the servo signal. For this reason, in Japanese Patent Application Laid-Open No. 2004-228561, direct current erasure is performed on the servo signal recording unit, and then recording is performed on the signal recording area of the servo signal by a magnetic field in the direction opposite to the direct current erasure. A method for obtaining a high reproduction output is shown. As a result, the servo signal can be reproduced more accurately and quickly, and the recording density of the magnetic signal can be further increased in the future.

  A magnetic head for writing a servo signal (hereinafter referred to as a servo signal recording head) is used for a magnetic core formed of a magnetic material having a high magnetic permeability, as shown, for example, in Patent Documents 1, 3, and 4 below. The coil is wound around. Such a magnetic head is called an electromagnetic induction type (inductive type) magnetic head because it performs recording on a magnetic recording medium using electromagnetic induction between a magnetic core and a coil.

  In recent years, in the field of magnetic recording, in order to reduce the size and increase the capacity of magnetic recording media, the recording density of magnetic signals has been further increased, and fine magnetic signals can be accurately recorded and reproduced. It is requested. Therefore, for example, a metal tape in which a ferromagnetic metal powder as a magnetic powder used for a magnetic layer for recording magnetic signals is coated and applied on a base film, or a vapor deposition tape in which a ferromagnetic metal material is directly deposited on the base film. Magnetic recording media exhibiting a high coercive force such as the above have been widely used.

  In order to enable recording on a magnetic recording medium exhibiting these high coercive forces, for example, an Fe-based alloy, Fe-Ta-based alloy, Fe-Ni-based alloy, Fe-Co-based alloy, etc. A magnetic head in which a metal magnetic material that exhibits high permeability and high saturation magnetic flux density is combined with, for example, a ferrite material has been proposed. For example, in Patent Documents 1, 3, and 4, the metal magnetic material and ferrite material are combined. A servo signal recording head is shown.

  In the servo signal recording head, a plurality of gaps (hereinafter referred to as Gap) having different inclinations are arranged with a predetermined interval. The gap material is made of a nonmagnetic material. It is also a well-known fact that the strength of the gap part increases when a metal film is deposited by various methods so as to cover the nonmagnetic material. This gap part can be produced by using a general photographic printing method that has been used for a long time.

  Further, the sliding surface of the servo signal recording head is given a flat mirror finish using a lens polishing apparatus or the like in order to obtain a good contact state with the magnetic tape.

  FIG. 49 shows an example of a recording pattern on the magnetic tape 60 that records the data signal and the servo signal independently as shown in Patent Document 2. In FIG. 49, servo band portions (Servo Bands 0 to 4) are regions where servo tracks Tr formed by arranging servo signals S of a predetermined pattern in the longitudinal direction, and data band portions (Data Bands 0 to 3). Is a plurality of data signal tracks Ta extending in the longitudinal direction in the width direction. The data band is formed so as to be sandwiched between two servo bands in the tape width direction.

  Therefore, for example, when the magnetic tape 60 has four data bands, five servo tracks are formed. In the illustrated example, five servo signals S5a tilted at a predetermined angle, five servo signals S5b tilted at the same angle in the opposite direction to this signal, four servo signals S4a tilted at a predetermined angle, The servo track Tr is formed by making four servo signals S4b inclined at the same angle in the opposite direction to this signal as one pattern and repeating this pattern.

  This servo signal is recorded by a servo signal recording head shown in, for example, Patent Documents 1, 3, and 4, in which a plurality of gaps having different inclinations are arranged on the sliding surface with a predetermined interval. Yes.

  FIG. 50 is a diagram for performing recording with a magnetic field in a direction opposite to the direct current erasure after performing direct current erasure on a servo signal recording portion (hereinafter referred to as a servo band portion) shown in Patent Document 2. FIG. 2 is a conceptual diagram of an apparatus for recording a servo signal S on a magnetic tape T, showing an example of a servo signal recording apparatus.

  Here, conventionally, a method of recording servo signals with a magnetic field in the opposite direction to the direct current erasure after performing direct current erasure on the servo band portion of the running recording medium is shown in FIG. This is performed by a servo band section DC erasing head (DC erasing unit 72) and a servo signal recording head (recording head unit 71), which are individually arranged on the signal recording device at positions separated from each other.

In FIG. 50, reference numeral 71 denotes a recording head unit in which a magnetic head (recording head) for recording the servo signal S is arranged. Reference numeral 72 denotes a DC erasing unit including a DC magnet that magnetizes the magnetic tape 60 before recording. Reference numeral 73 denotes a reproducing head unit in which a magnetic head (reproducing head) for reproducing the servo signal S is arranged. In addition, the apparatus includes a transport unit that transports the magnetic tape 60 from the tape take-out unit 74 to the tape take-up unit 75 in the longitudinal direction.
Japanese Patent No. 3158015 JP 2005-166230 A Special table 2002-538565 JP 2002-170204 A

  However, in the case of a system in which the servo band portion DC erasing head and the servo signal recording head are individually arranged on the servo signal recording device at positions separated from each other, the accuracy of the tape running system of the servo signal recording device and the magnetic tape Due to the variation in the tape running position in the tape width direction due to the variation in the width, a maximum of about 50 μm is provided between the area where the DC erasing on the magnetic tape is performed by the servo band DC erasing head and the gap position of the servo signal recording head. There was a problem that a high playback output could not be obtained stably during servo signal playback.

  To solve this problem, for example, as shown in FIG. 51, the gap position of the servo signal recording head is always DC erased even if the DC erase width is increased by 50 μm above and below the servo bandwidth and the tape running position fluctuates. As a result of entering the area, the DC erasure signal outside the servo band part interferes with the data signal in the data band part, and the data signal cannot be reproduced normally.

  Further, as shown in FIG. 52, the servo band unit DC erasing head is used for the purpose of reducing the influence of the tape running system accuracy of the servo signal recording device and the running position variation in the tape width direction caused by the variation in the magnetic tape width. FIG. 53 shows a method in which Haa and the servo signal recording head Hbb are brought close to each other, the mutual gap positions are positioned and fixed on the same pedestal 80 with high accuracy, and then the pedestal 80 is mounted on the servo signal recording apparatus. As shown in FIG. 4, there is a problem of gap displacement between the servo band DC erasing head Haa and the servo signal recording head Hbb due to an alignment error in the head mounting angle (θ) direction with respect to the tape running direction.

  Furthermore, in order to reduce the influence of the tape position in the tape width direction due to the variation in the tape running system of the servo signal recording device and the variation in the tape width direction due to the variation in the magnetic tape width, and the influence of the θ direction alignment error, FIG. As shown in the figure, the servo band portion DC erasing head Haa and the servo signal recording head Hbb are integrated by joining the gap positions of the gaps with high accuracy, and a magnetic head in which the distance between the gaps is made as close as possible is manufactured. As a result, a step of 1 to 2 μm occurs between the sliding surfaces of the magnetic heads Haa and Hbb at the time of joining, and this step does not provide a good contact state with the magnetic tape during servo signal recording. There was a problem that the signal could not be recorded.

  Further, for the purpose of removing the effect of the step between the sliding surfaces of the magnetic heads Haa and Hbb generated by the above-mentioned joining, a flat mirror finish is applied to the sliding surface using a lens polishing apparatus after joining. As a result, the thickness of the metal magnetic material formed on the sliding surface of the magnetic head is reduced by an amount corresponding to the level difference, and the magnetic field strength necessary for signal recording cannot be obtained, and servo signals cannot be recorded. Problem has occurred.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a magnetic head capable of performing good direct current erasure and servo signal recording, thereby obtaining a stable reproduction output during servo signal reproduction, and The object is to provide a method of manufacturing a magnetic head.

  The magnetic head according to claim 1 for solving the above-described problem is a magnetic head used in a magnetic recording medium having a data signal recording portion and a servo signal recording portion in a magnetic layer, and a sliding surface with the magnetic recording medium. A magnetic magnetic film for direct current erasure on the servo signal recording unit, and a magnetic magnetic film on the surface as a sliding surface with the magnetic recording medium, A servo signal recording magnetic head for recording a servo signal in a signal recording area of the servo signal recording unit by a magnetic field in a direction opposite to that of the DC erasing is integrated close to the magnetic recording head of the DC erasing magnetic head. The film formation surface and the metal magnetic film formation surface of the servo signal recording magnetic head are formed in the same plane.

  According to the above configuration, the formation surface of the metal magnetic film serving as the sliding surface of the DC erasing magnetic head and the formation surface of the metal magnetic film serving as the sliding surface of the servo signal recording magnetic head are in the same plane. As a result, even if the metal magnetic film serving as the sliding surface is flat mirror-finished, the thickness of the metal magnetic film due to the step difference between the heads does not occur, and a good signal recording magnetic field strength can be obtained. it can.

  Further, the formation surface of the metal magnetic film that becomes the sliding surface of the DC erase magnetic head and the formation surface of the metal magnetic film that becomes the sliding surface of the magnetic head for servo signal recording are in the same plane. No step is generated between the metal magnetic films on the sliding surface of the magnetic head, and it is possible to obtain a good contact state with the magnetic tape during servo signal recording.

  The method for manufacturing a magnetic head according to claim 7 is the method for manufacturing a magnetic head used in a magnetic recording medium having a data signal recording portion and a servo signal recording portion in a magnetic layer, wherein one surface of the first magnetic core substrate is used. Forming a plurality of grooves having a predetermined depth at predetermined intervals, and filling each of the grooves with a first nonmagnetic material; and one first nonmagnetic material among the plurality of first nonmagnetic materials. Forming a gap of a DC erasing magnetic head and a servo signal recording magnetic head on a pair of first nonmagnetic materials adjacent to each other, and the two gaps and the first nonmagnetic material Forming a metal magnetic film on one surface of the first magnetic core substrate, and removing the metal magnetic film on the one first nonmagnetic material located between the pair of nonmagnetic materials And the above Polishing the other surface of the magnetic core substrate until the first non-magnetic material is exposed, and then forming a bonding metal film on the surface; and on one surface of the second magnetic core substrate Forming a groove having a predetermined depth, filling the groove with a second nonmagnetic material, and polishing the other surface of the second magnetic core substrate until the second nonmagnetic material is exposed. And forming a bonding metal film on the surface, and bonding a bonding metal film of the first magnetic core substrate and a bonding metal film of the second magnetic core substrate. It is characterized by having prepared.

  According to the above configuration, an integrated magnetic head in which a step between the DC erasing magnetic head and the servo signal recording magnetic head is eliminated can be manufactured.

  A magnetic head according to a second aspect of the present invention is the magnetic head according to the first aspect, wherein the direct-current erasing magnetism is between the metallic magnetic film of the direct-current erasing magnetic head and the metallic magnetic film of the servo signal recording magnetic head. The sliding surface with the magnetic tape is formed in the same plane as the sliding surface of the magnetic metal film of the head with the magnetic tape and the sliding surface of the magnetic magnetic film of the servo signal recording magnetic head with the magnetic tape. It is characterized by interposing a magnetic material.

  According to the above configuration, since the nonmagnetic material is interposed between the metal magnetic film of the DC erasing magnetic head and the magnetic magnetic film of the servo signal recording magnetic head, the magnetic tape and the sliding surface of the magnetic head This gap is not generated, and it is not affected by the magnetic powder falling off from the magnetic layer during traveling, and the DC erasure signal and the servo signal can be recorded stably.

  The method for manufacturing a magnetic head according to claim 8 is the method for manufacturing a magnetic head used for a magnetic recording medium having a data signal recording portion and a servo signal recording portion in a magnetic layer, wherein one surface of the first magnetic core substrate is used. Forming a plurality of grooves having a predetermined depth at predetermined intervals, and filling each of the grooves with a first nonmagnetic material; and one first nonmagnetic material among the plurality of first nonmagnetic materials. Forming a gap of a DC erasing magnetic head and a servo signal recording magnetic head on a pair of first nonmagnetic materials adjacent to each other, and the two gaps and the first nonmagnetic material Forming a metal magnetic film on one surface of the first magnetic core substrate, and removing the metal magnetic film on the one first nonmagnetic material located between the pair of nonmagnetic materials And the gold Filling the first non-magnetic material from which the magnetic film has been removed with the second non-magnetic material and the other surface of the first magnetic core substrate until the first non-magnetic material is exposed. After polishing, a step of forming a bonding metal film on the surface, a groove having a predetermined depth is formed on one surface of the second magnetic core substrate, and the groove is filled with a third nonmagnetic material. Polishing the other surface of the second magnetic core substrate until the third nonmagnetic material is exposed, and then forming a bonding metal film on the surface, and the first magnetic And a step of bonding a metal film for bonding the core substrate and a metal film for bonding the second magnetic core substrate.

  A method for manufacturing a magnetic head according to claim 9 is the method for manufacturing a magnetic head used in a magnetic recording medium having a data signal recording portion and a servo signal recording portion in a magnetic layer, wherein one surface of the first magnetic core substrate is used. Forming a plurality of grooves having a predetermined depth at predetermined intervals, and filling each of the grooves with a first nonmagnetic material; and one first nonmagnetic material among the plurality of first nonmagnetic materials. A gap for a DC erasing magnetic head and a servo signal recording magnetic head are formed on a pair of first nonmagnetic materials adjacent to each other, and a second nonmagnetic material is formed on the one first nonmagnetic material. Forming a magnetic material; forming a metal magnetic film on one surface of the first magnetic core substrate including the two gaps, the first nonmagnetic material and the second nonmagnetic material; The metal magnetic film is formed Polishing one surface of one magnetic core substrate uniformly, and polishing the other surface of the first magnetic core substrate until the first nonmagnetic material is exposed, and then bonding the surface onto the surface Forming a metal film, forming a groove of a predetermined depth on one surface of the second magnetic core substrate, and filling the groove with a third nonmagnetic material, and the second magnetic core Polishing the other surface of the substrate until the third non-magnetic material is exposed, and forming a bonding metal film on the surface; and a bonding metal film of the first magnetic core substrate; A step of bonding a metal film for bonding the second magnetic core substrate.

  According to the above configuration, it is possible to manufacture a magnetic head that is not affected by the magnetic powder that falls off the magnetic layer during traveling.

  According to a third or fourth aspect of the present invention, in the magnetic head according to the first or second aspect, a conductive nonmagnetic thin film material is interposed between the DC erasing magnetic head and the servo signal recording magnetic head. It is characterized by being.

  According to the above configuration, when the servo signal is recorded, the servo signal magnetic field leaking from the magnetic core of the servo signal recording head enters the magnetic core of the DC erasing head into the DC erasing magnetic head and the servo signal recording magnetic head. Since it is interrupted by the conductive nonmagnetic thin film material arranged at the junction, stable DC erasure can be performed, and variations in reproduction output during servo signal reproduction can be reduced.

  A method for manufacturing a magnetic head according to claim 10 is the method for manufacturing a magnetic head used in a magnetic recording medium having a data signal recording portion and a servo signal recording portion in a magnetic layer, wherein one surface of the first magnetic core substrate is used. Forming a first groove having a predetermined depth on the inner surface of the groove, forming a first conductive nonmagnetic thin film material on the inner surface of the groove, and forming the first groove on one surface of the first magnetic core substrate. A pair of second grooves are formed at portions adjacent to the grooves at a predetermined interval, and the first nonmagnetic material is filled in the pair of second grooves and the first conductive nonmagnetic thin film material formation surface. Forming a gap of a magnetic head for DC erasure and a gap of a magnetic head for recording a servo signal on the first nonmagnetic material filled in the pair of second grooves, and Including a gap and a first non-magnetic material; Forming a metal magnetic film on one surface of the magnetic core substrate, removing the metal magnetic film on the first nonmagnetic material in the first groove, and Polishing the other surface until the first nonmagnetic material is exposed and then forming a bonding metal film on the surface; and forming a first depth of a predetermined depth on one surface of the second magnetic core substrate. And forming a second conductive nonmagnetic thin film material on the inner surface of the groove, and filling a second nonmagnetic material on the second conductive nonmagnetic thin film material forming surface. And polishing the other surface of the second magnetic core substrate until the second non-magnetic material is exposed, and then forming a bonding metal film on the surface, and the first magnetic core Bonding a metal film for bonding the substrate and a metal film for bonding the second magnetic core substrate Tsu is characterized in that a flop.

  According to the above configuration, it is possible to manufacture a magnetic head that prevents a servo signal magnetic field leaking from the magnetic core of the servo signal recording magnetic head from entering the magnetic core of the DC erasing magnetic head during servo signal recording.

  The magnetic head according to claims 5 and 6 is characterized in that, in claim 3 or 4, the thickness of the conductive nonmagnetic thin film material is 5 μm or less.

  According to the above configuration, since the influence of the stress generated by the difference in thermal expansion coefficient between the ferrite material forming the magnetic core of the magnetic head and the conductive nonmagnetic material can be reduced, cracks are not generated in the ferrite material forming the magnetic core. It does not occur and there is no significant drop in yield due to cracks.

(1) According to the first to sixth aspects of the present invention, the magnetic magnetic film of the two magnetic heads, wherein the magnetic head for DC erasing and the magnetic head for servo signal recording are provided close to each other and serve as a sliding surface of the magnetic tape Since they are formed on the same plane, good direct current erasure and servo signal recording can be performed. As a result, a stable reproduction output can be obtained during servo signal reproduction.
(2) According to the inventions described in claims 7 to 10, the magnetic magnetic films of the two magnetic heads which are close to the DC erasing magnetic head and the servo signal recording magnetic head and which serve as a sliding surface of the magnetic tape The magnetic heads can be manufactured by forming them in the same plane and thereby performing good DC erasure and servo signal recording.
(3) According to the first aspect of the present invention, the metal magnetic film forming surface that becomes the sliding surface of the DC erasing magnetic head and the metal magnetic film that becomes the sliding surface of the servo signal recording magnetic head Since the formation surface is in the same plane, even if the metal magnetic film serving as the sliding surface is subjected to a flat mirror finish, the thickness of the metal magnetic film due to the step difference between the heads does not occur. The signal recording magnetic field strength can be obtained.

  Further, the formation surface of the metal magnetic film that becomes the sliding surface of the DC erase magnetic head and the formation surface of the metal magnetic film that becomes the sliding surface of the magnetic head for servo signal recording are in the same plane. No step is generated between the metal magnetic films on the sliding surface of the magnetic head, and it is possible to obtain a good contact state with the magnetic tape during servo signal recording.

  In addition, the servo band unit DC erasure head and servo signal recording head are integrated, and the distance between the gaps is made as close as possible. It is possible to reduce the influence of the gap gap between the head and the servo signal recording head.

  In addition, the servo band DC erasing head and servo signal recording head are integrated, and the distance between the gaps is made as close as possible, resulting in the accuracy of the tape running system of the servo signal recording device and the variation in magnetic tape width. The influence of variation in the tape running position in the width direction can be reduced, and the area where DC erasing on the magnetic tape is performed by the servo band portion DC erasing head can be accurately matched with the gap position of the servo signal recording head.

  Furthermore, the DC erase signal on the outer side of the servo band portion is obtained by accurately matching the area where the DC erase on the magnetic tape is performed with the servo band portion DC erase head and the Gsp position of the servo signal recording head. There is no interference with the data signal in the data band part.

Furthermore, by accurately matching the area where the DC erase on the magnetic tape was performed with the servo band DC erase head and the gap position of the servo signal recording head, a high reproduction output can be stably obtained during servo signal reproduction. I can do it.
(4) According to the invention described in claim 2, since there is no dividing groove in which the magnetic powder falling off from the magnetic layer is deposited when the magnetic tape runs, the magnetic tape as shown in FIGS. Since no erasure signal and servo signal can be recorded with a sufficient recording magnetic field applied to the magnetic tape, the reproduction output does not decrease during servo signal reproduction. Further, there is no problem that the servo signal cannot be recorded by the head clog. Thereby, it is possible to record the DC erasure signal and the servo signal stably.
(5) According to the inventions described in claims 8 and 9, it is possible to manufacture a magnetic head which is not affected by the magnetic powder falling off from the magnetic layer during traveling.
(6) According to the third and fourth aspects of the present invention, when the servo signal is recorded, the servo signal magnetic field leaking from the magnetic core of the servo signal recording head enters the magnetic core of the DC erasing head. Is blocked by a conductive nonmagnetic thin film material placed at the junction between the magnetic head for recording and the magnetic head for recording servo signals, enabling stable DC erasure and reducing variations in playback output during servo signal playback it can.
(7) According to the tenth aspect of the invention, the magnetic field in which the servo signal magnetic field leaking from the magnetic core of the servo signal recording magnetic head is prevented from entering the magnetic core of the DC erasing magnetic head during servo signal recording. A head can be manufactured.
(8) According to the inventions described in claims 5 and 6, since the influence of the stress generated by the difference in thermal expansion coefficient between the ferrite material forming the magnetic core of the magnetic head and the conductive nonmagnetic material can be reduced, Cracks do not occur in the ferrite material that forms the magnetic core, and there is no significant drop in yield due to cracks.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments.

  FIG. 1 is a schematic view showing the configuration of a magnetic head according to the present invention.

  The magnetic head of the present invention has a metal magnetic film on the surface as a sliding surface of a recording medium (magnetic tape), and has a plurality of gap portions in a direction perpendicular to the magnetic tape sliding direction in the metal magnetic film. A servo signal recording magnetic head portion Hb having a DC erasing magnetic head portion Ha and a metal magnetic film serving as a sliding surface of the magnetic tape on the surface, and having a plurality of gap portions with different inclinations in the metal magnetic film. Structure of bulk thin film head used for writing servo signal in magnetic head Hb for servo signal recording after writing DC erase signal in magnetic head for DC erasing on magnetic tape that is integrated and running It is an example.

  In this configuration example, a magnetic core half 5a for a DC erasing head having a metal magnetic film 4a on the surface serving as a sliding surface with the recording medium and constituting a magnetic path of a DC erasing signal, and a sliding surface with the recording medium And a front core 1 in which a servo signal recording head magnetic core half 5b having a metal magnetic film 4b constituting a servo signal magnetic path on the surface is joined and integrated via a nonmagnetic material 7b, and a winding groove A magnetic core half 10a for DC erasing head having 9a and a back core 2 in which a magnetic core half 10b for servo signal recording head having a winding groove 9b is joined and integrated through a nonmagnetic material 7a. And a DC erasing / servo-recording integrated magnetic core joined by the joining portion 3 and an exciting coil (not shown) in which a conducting wire is wound around the winding grooves 9a and 9b of the magnetic core.

  Here, the metal magnetic films 4a and 4b are made of Fe-based microcrystalline films or films made of NiFe or other soft magnetic alloys having a high saturation magnetic flux density similar to this, with a thickness of several μm. It is. Gap 4c and 4d are writing patterns made of a non-magnetic material that is formed on the base glasses 8a and 8b and has a height that reaches the sliding surface of the recording medium so as to divide the metal magnetic films 4a and 4b. When recording on the recording medium, the gap patterns 4c and 4d prevent the magnetic flux generated when a current flows through the exciting coil, so that the gap pattern can be recorded on the traveling recording medium.

  The material constituting the magnetic core halves 5a, 5b, 10a, 10b is a conventionally known magnetic material, and may be either single crystal ferrite or polycrystalline ferrite. For example, Mn—Zn ferrite and the like can be mentioned.

  The magnetic core halves 5a and 5b constituting the front core 1 have grooves extending in the width direction W of the magnetic recording medium immediately below the gaps 4c and 4d of the metal magnetic films 4a and 4b, and hard nonmagnetic materials are further provided in the grooves. The base glass 8a, 8b is filled and fused. The magnetic core halves 5a and 5b are joined and integrated by a hard nonmagnetic material 7b. These hard nonmagnetic materials 7b, 8a, and 8b may be any nonmagnetic material that can be fused to the magnetic core halves 5a and 5b to ensure a certain level of strength. For example, in consideration of the heat treatment temperature of the metal magnetic film, it is preferable to use refractory glass having a glass transition temperature higher than the heat treatment temperature of the metal magnetic film. Moreover, the magnetic core halves 5a and 5b have winding grooves 6a and 6b that are open on the side opposite to the surface on which the metal magnetic films 4a and 4b are formed.

  2 (cross-sectional view of the front core 1), the metal magnetic film forming surface 12 is formed before the metal magnetic films 4a and 4b are formed. The magnetic core halves 5a and 5b, the nonmagnetic material 7b, In a state where the base glasses 8a and 8b are integrated, a flat mirror finish without a step is applied using a lens polishing apparatus or the like. Magnetic gaps 4c, 4d are formed by photolithography using a semiconductor mask in which a DC erase signal gap pattern and a servo signal gap pattern are arranged with high precision on the mirror-finished metal magnetic film forming surface 12. Are simultaneously formed, and then the metal magnetic films 4a and 4b are formed simultaneously. The metal magnetic film forming surface 12 of the front core 1 has a flat mirror finish without a step in a state where the magnetic core halves 5a and 5b, the nonmagnetic material 7b, and the base glasses 8a and 8b are integrated. For this reason, there is no step between the servo band portion DC erasing head portion and the metal magnetic films 4a and 4b of the servo signal recording head portion.

  Also, the tape sliding surface width 4e of the front core shown in FIG. 2 is preferably 4 mm or less in order to ensure a good contact state with the tape during recording of the DC erasure signal and the servo signal. When it exceeds 4 mm, the tape is lifted on the sliding surface, and there is a problem that recording cannot be performed due to a spacing loss due to the lift.

  The distance 4f between the DC erase signal recording gap 4c and the servo signal recording gap 4d depends on the influence of the alignment error in the direction of the head mounting angle (θ) with respect to the tape running direction and the magnetic tape from above the DC erase signal recording gap 4c. In order to reduce the influence of the positional deviation in the width direction of the magnetic tape, which occurs while moving on the servo signal recording gap 4d, it is preferable to set it to 2.5 mm or less.

  In addition, the direct current erase signal recording gap 4c and the servo signal recording gap 4d of the magnetic head according to the present invention are formed by photolithography using a semiconductor mask in which patterns are arranged with high precision. The relationship can be controlled with high accuracy. By utilizing this, as shown in FIG. 3, the width of the DC erase signal recording gap can be set wider than the width of the servo signal recording gap within a range not interfering with the data band portion. As a result, even if there is a misalignment in the width direction of the magnetic tape that occurs while the magnetic tape moves from the DC erase signal recording gap 4c to the servo signal recording gap 4d, The band DC erasing head can be accommodated in the area where DC erasing is performed. FIG. 3 shows an example in the LTO (Linear Tape Open) format. In this format, the width of the DC erase signal recording gap can be 194 μm and the width of the servo signal recording gap can be 186 μm. .

  With the above configuration, the magnetic head according to the present invention can accurately match the area where the DC erase on the magnetic tape is performed with the servo band unit DC erase head and the gap position of the servo signal recording head. Further, there is no step between the metallic magnetic film of the DC erasing magnetic head and the metallic magnetic film of the servo signal recording magnetic head, and a good contact state with the magnetic tape can be ensured. Moreover, even if the metal magnetic film serving as the sliding surface is subjected to a flat mirror finish, the thickness of the metal magnetic film due to the step difference between the heads does not occur, and a good signal recording magnetic field strength can be obtained. .

Next, a method for manufacturing the magnetic head shown in FIG. 1 will be described. Hereinafter, an embodiment of a method of manufacturing a magnetic head according to the present invention will be described step by step with reference to FIGS.
(Step S11) Non-magnetic that joins the servo band part DC erasing head, the gap part of the servo signal recording head, and both magnetic cores to one main surface of the magnetic core substrate 13 which is the original plate of the plurality of magnetic core halves 5 A groove corresponding to the position of the material (7b) is formed, and the hard nonmagnetic material is filled and fused in the groove, and the hard nonmagnetic material protruding at this time is polished to form the base glass 8 (FIG. 4). At the same time, polishing is performed so that the metal magnetic film forming surface 12 including the base glass 8 becomes flat. Further, the flatness (undulation of the unevenness) of the surface is preferably 100 nm or less from one end to the other end in the magnetic tape running direction and the width direction.
(Step S12) Next, as shown in FIG. 5, the metal magnetic film 4 is formed on the surface of the magnetic core substrate 13 where the metal magnetic film is formed.

  Specifically, first, a nonmagnetic hard film such as silicon dioxide is formed by sputtering on substantially the entire surface of the magnetic core substrate 13 on which the metal magnetic film is formed. Next, a resist material is uniformly applied to the non-magnetic hard film with a uniform thickness and a semiconductor mask on which a gap pattern is applied is used to correspond to the gap portion of the servo band portion DC erase head and the servo signal recording head. A Gap pattern is aligned on the base glass 8 and exposed to light. Then, the magnetic core substrate 13 is immersed in a developing solution for a predetermined time, and unnecessary resists according to the mask are dissolved and removed, leaving only the necessary shapes. Next, reactive ion etching or ion etching is used to remove unnecessary non-magnetic hard film exposed from the remaining resist, and then the remaining Gap / resist pillars are washed with a solvent to remove the base. A gap part is obtained on the glass. Further, in this gap formation step, the base glass 8 at a position where no gap is formed becomes a nonmagnetic material 7b for joining the magnetic cores of both the servo band portion DC erasing head and the servo signal recording head.

Next, a metal magnetic film having a high saturation magnetic flux density is formed on the metal magnetic film forming surface 12 by any of sputtering, vapor deposition, and plasma CVD. Thereafter, heat treatment is performed on the magnetic core substrate 13 to obtain good soft magnetic properties for the metal magnetic film 4.
(Step S13) Next, as shown in FIG. 6, on the nonmagnetic material 7b that joins both magnetic cores so that the metal magnetic films of the servo band portion DC erasing head and the servo signal recording head do not interfere magnetically. The metal magnetic film is removed by the dividing groove 13a. Thereafter, a shoulder drop groove 13b having an inclination is formed for the purpose of allowing the magnetic tape to smoothly enter the sliding surface when the magnetic head is formed.

  Further, since the metal magnetic film formed in step S12 is formed in a shape along the surface shape of the magnetic core substrate 13, in the whole substrate 13, only the gap portions 4c and 4d are just above the gap portions. The metal magnetic film protrudes by the height of 4c and 4d. Since this protrusion is in a state where a very small area protrudes from the entire area, the entire surface can be shaved uniformly by buff polishing or lens polishing, and the metal magnetic film 4 is thus completed.

Next, as shown in FIG. 7, the magnetic core substrate 13 is inverted to form the winding groove 6 on the main surface opposite to the metal magnetic film forming surface (tape sliding surface), and then the winding grooves 6 other than the main groove on the main surface are formed. The lens 14 is polished until the nonmagnetic material 7b is exposed at the bonding surface. In addition, since a metal film for bonding is formed in a subsequent process, the surface roughness Ra of the bonding surface 14 is desirably 10 nm or less. Further, the flatness (undulation of the unevenness) of the surface is preferably 100 nm or less from one end to the other end in the magnetic tape running direction and the width direction.
(Step S14) A vapor deposition film of a metal film is formed on the bonding surface 14 of the magnetic core substrate 13 (FIG. 8). Here, the metal film preferably has a two-layer structure, and the first metal film 15a is for ensuring adhesion between the magnetic core substrate 13 and the second metal film 15b. It is a thin film made of Cr or Ti having a thickness of about 50 nm. The second metal film 15b is a metal thin film that can be diffusion bonded at a temperature below the glass transition point of the hard non-magnetic material, and has a uniform thickness of, for example, 10 to 200 nm, preferably 10 to 100 nm. It is a deposited film such as Au.
(Step S15) As shown in FIG. 9, the servo band portion DC erasing head and servo signal recording are formed on the bonding surface 17a of the magnetic core substrate 16 which is the original plate of the plurality of magnetic core halves 10 to be bonded to the magnetic core substrate 13. After forming a groove corresponding to the position of the nonmagnetic material 7a to which the magnetic core of the head is bonded and filling the groove with a hard nonmagnetic material, the protruding hard nonmagnetic material is polished to smooth the bonding surface 17a. To do.
(Step S16) Next, as shown in FIG. 10, with respect to the main surface 17b opposite to the bonding surface 17a of the magnetic core substrate 16, the flatness of the surface is from one end to the other end in the recording medium width direction. Polishing is performed until the nonmagnetic material 7a is exposed to the main surface 17b so as to be 100 nm or less, and then the winding groove 9 corresponding to the magnetic core half body 10 is formed on the bonding surface 17a. Thereafter, the bonding surface 17a is finished flat by lens polishing or the like. In addition, since a metal film for bonding is formed in a subsequent process, the surface roughness Ra of the bonding surface 17a is desirably 10 nm or less. The flatness of the surface is preferably 100 nm or less from one end to the other end in the recording medium running direction L and the recording medium width direction W.
(Step S17) Next, as shown in FIG. 11, the first metal film 15a / second metal film 15b deposited film similar to step S14 is formed on the bonding surface 17a of the magnetic core substrate 16 as shown in FIG.
(Step S18) As shown in FIG. 12, using the magnetic core substrate 13 after step S14 and the magnetic core substrate 16 after step S16, the bonding surface 14 of the magnetic core substrate 13 and the bonding surface 17a of the magnetic core substrate 16 Are aligned and the winding groove 6 of the magnetic core substrate 13 and the winding groove 9 of the magnetic core substrate 16 are aligned, and the second metal films 15b are brought into contact with each other to perform low-temperature metal diffusion bonding.

Here, the low temperature metal diffusion bonding refers to the second metal film 15b provided on the bonding surface 14 of the magnetic core substrate 13 and the second metal film 15b provided on the bonding surface 17a of the magnetic core substrate 16 described above. The constituent atoms of the second metal film 15b are mutually diffused and bonded at a temperature not higher than the glass transition point of the hard nonmagnetic material. Specifically, in the case of the second metal film 15b made of Au, a heating temperature of 150 to 300 ° C. and a processing time of several minutes to several hours in a state where both the second metal films 15b are brought into contact with each other with a pressure of about 10 to 20 MPa. Bonding is possible by this heat treatment.
(Step S19) Finally, as shown in FIG. 13, the combined substrate in which the magnetic core substrate 13 and the magnetic core substrate 16 are joined is cut at the cutting position aa ′, and the magnets for each row constituting the magnetic core are cut. Get the core block.

  Thereafter, a conducting wire is wound around the winding grooves 6 and 9 of the obtained magnetic core to form an exciting coil, thereby completing the magnetic head shown in FIG.

By the manufacturing method of the present embodiment example, the area where the DC erase on the magnetic tape was performed on the servo band portion DC erase head and the gap position of the servo signal recording head exactly matched, and the metal of the magnetic head for DC erase There is no step between the magnetic film and the magnetic magnetic film of the magnetic head for servo signal recording, ensuring good contact with the magnetic tape, and obtaining good signal recording magnetic field strength. In a system in which servo signals are recorded by a magnetic field in the opposite direction to the direct current erasure after performing direct current erasure on the servo band portion of the traveling recording medium, a high reproduction output can be stably obtained during servo signal reproduction. It is possible to realize a magnetic head integrated with a direct current erasing head and servo signal recording head.
(Example 1)
Hereinafter, an example in which the magnetic head of the present invention was actually manufactured will be described.

In accordance with the magnetic head manufacturing method described above, a magnetic head for 1/2 inch width magnetic tape was manufactured under the following conditions.
(1) Metal magnetic film 4; Fe-Ta microcrystalline film Thickness: 3 μm
(2) Magnetic cores 5 and 10; ferrite substrate (dimensions 30 × 30 × 1.5 mm)
(3) Hard non-magnetic material; glass transition temperature 550 ° C
(4) Metal magnetic film heat treatment temperature: 480 ° C
(5) Metal magnetic film forming surface 12 flatness: 90 nm
(6) Tape sliding surface width 4e; 3.5mm
(7) DC erase signal recording gap / servo signal recording gap distance 4f; 2.3 mm
(8) Gap width for recording DC erasure signal; 194 μm
(9) Gap width for servo signal recording; 186 μm
The magnetic head manufactured under the above conditions is attached to the recording head unit 71 of the servo signal recording apparatus shown in FIG. 50, the DC erasing unit 72 is removed, and this magnetic head is applied to the 1/2 inch wide magnetic tape 60 for LTO format. The DC erase signal and servo signal were recorded, and the reproduction output was confirmed by the reproduction head unit 73 of the apparatus. The results are as shown in Table 1 below, and it was confirmed that a reproduction output approximately twice as large as that obtained when there was no DC erasure signal was stably obtained with a variation of 0.3 dB or less. In addition, as a result of recording and evaluating data signals on this magnetic tape with the LTO-2 drive, it was confirmed that the data signals could be normally reproduced in all data bands.

(Comparative example)
The DC erase head Ha and the servo signal recording head Hb, which are individually manufactured under the same conditions as in the embodiment, are attached to the DC erase unit 72 and the recording head unit 71 of the servo signal recording apparatus shown in FIG. A DC erase signal and a servo signal were recorded on the 2-inch wide magnetic tape 60, and the reproduction output was confirmed by the reproduction head unit 73 of the apparatus. The result is as shown in Table 2 below. Although the reproduction output is about twice as large as the maximum value when compared with the case where there is no DC erasure signal, the variation is about 3 to 4 dB, and the stable reproduction output is obtained. It was confirmed that it could not be obtained.

  Next, another embodiment of the present invention will be described. FIG. 14 shows the magnetic head of FIG. 1. This magnetic head causes magnetic interference between the magnetic magnetic films of the servo band portion DC erasing head Ha and the servo signal recording head Hb on the sliding surface of the magnetic tape. For the purpose of avoiding, since the dividing groove 13a is formed, when the magnetic tape travels, as shown in FIG. 15, the magnetic powder 61 falling off from the magnetic layer enters the dividing groove 13a and accumulates, A gap is generated between the magnetic tape 60 and the sliding surface, and because of the spacing loss due to this gap, the erase signal and the servo signal are recorded in a state where a sufficient recording magnetic field is not applied to the magnetic tape. There was a problem that the playback output decreased.

  Further, as shown in FIG. 16, the deposited magnetic powder 61 covers the gap 4d of the servo signal recording head (head clog), thereby causing a problem that the servo signal cannot be recorded on the magnetic tape.

  In this embodiment, in order to solve the above problem, the magnetic head is configured as shown in FIG. In this configuration example, a magnetic core half 5a for a DC erasing head having a metal magnetic film 4a on the surface serving as a sliding surface with the recording medium and constituting a magnetic path of a DC erasing signal, and a sliding surface with the recording medium Servo signal recording head magnetic core half 5b having a metal magnetic film 4b constituting the magnetic path of the servo signal on the surface is joined and integrated through nonmagnetic material 7b, and further, metal magnetic film 4a and metal magnetic film Front core 1 in which the film 4b is divided by a nonmagnetic material 7c, a magnetic core half for a DC erasure head having a winding groove 9a, and a magnetic core half for a servo signal recording head having a winding groove 9b A back core 2 in which 10b is joined and integrated via a non-magnetic material 7a and joined at a joint 3, a DC erase / servo recording integrated magnetic core, and a winding groove 9a of the magnetic core And an exciting coil (not shown) in which a conducting wire is wound around 9b The

  Here, the metal magnetic films 4a and 4b are made of Fe-based microcrystalline films or films made of NiFe or other soft magnetic alloys having a high saturation magnetic flux density similar to this, with a thickness of several μm. It is. Gap 4c, 4d is a writing pattern (gap) made of a non-magnetic material formed on the base glass 8a, 8b and having a height reaching the recording medium sliding surface so as to divide the metal magnetic films 4a, 4b. . When recording on the recording medium, the gap patterns 4c and 4d prevent the magnetic flux generated when a current flows through the exciting coil, so that the gap pattern can be recorded on the traveling recording medium.

  The material constituting the magnetic core halves 5a, 5b, 10a, 10b is a conventionally known magnetic material, and may be either single crystal ferrite or polycrystalline ferrite. For example, Mn—Zn ferrite and the like can be mentioned.

  The magnetic core halves 5a and 5b constituting the front core 1 have grooves extending in the width direction W of the magnetic recording medium immediately below the gaps 4c and 4d of the metal magnetic films 4a and 4b, and hard nonmagnetic materials are further provided in the grooves. The base glass 8a, 8b is filled and fused. The magnetic core halves 5a and 5b are joined and integrated by a hard nonmagnetic material 7b. These hard nonmagnetic materials 7b, 8a, and 8b may be any nonmagnetic material that can be fused to the magnetic core halves 5a and 5b to ensure a certain level of strength. For example, in consideration of the heat treatment temperature of the metal magnetic film, it is preferable to use refractory glass having a glass transition temperature higher than the heat treatment temperature of the metal magnetic film. Moreover, the magnetic core halves 5a and 5b have winding grooves 6a and 6b that are open on the side opposite to the surface on which the metal magnetic films 4a and 4b are formed.

  Further, the metal magnetic film forming surface 12 shown in FIG. 18 (cross-sectional view of the front core 1) is provided with the magnetic core halves 5a and 5b, the nonmagnetic material 7b, before the metal magnetic films 4a and 4b are formed. In a state where the base glasses 8a and 8b are integrated, a flat mirror finish without a step is applied using a lens polishing apparatus or the like. Magnetic gaps 4c, 4d are formed by photolithography using a semiconductor mask in which a DC erase signal gap pattern and a servo signal gap pattern are arranged with high precision on the mirror-finished metal magnetic film forming surface 12. Are simultaneously formed, and then the metal magnetic films 4a and 4b are formed simultaneously.

Further, the nonmagnetic material 7c for separating the metal magnetic film 4a and the metal magnetic film 4b is not preferably a resin due to the problem of friction during running of the magnetic tape, and nonmagnetic metals such as Cr, Au and Ag, SiO ₂ , Al ₂ Oxides such as O ₃ , Cr ₂ O ₃ and Zr ₂ O ₃ are preferred.

  With the above configuration, the magnetic head of the present invention can eliminate the influence of the magnetic powder falling off from the magnetic layer when the magnetic tape travels, reducing the reproduction output during servo signal reproduction, and the head clog. Can prevent this problem.

Next, a first example of the method of manufacturing the magnetic head (FIG. 17) according to the present embodiment will be described step by step with reference to FIGS.
(Step S21) First, in FIG. 19, on one main surface of a magnetic core substrate 13 which is an original plate of a plurality of magnetic core halves 5, a servo band portion DC erase head, a gap portion of a servo signal recording head, and both magnetic cores A groove corresponding to the position of the nonmagnetic material to be bonded is formed, the hard nonmagnetic material is filled in the groove and fused, and the protruding hard nonmagnetic material is polished to form the base glass 8. . At the same time, polishing is performed so that the metal magnetic film forming surface 12 including the base glass 8 becomes flat. Further, the flatness (undulation of the unevenness) of the surface is preferably 100 nm or less from one end to the other end in the magnetic tape running direction and the width direction.
(Step S22) Next, as shown in FIG. 20, the metal magnetic film 4 and the gap portions 4c and 4d are formed on the metal magnetic film forming surface of the magnetic core substrate 13 (FIG. 7). Specifically, first, a nonmagnetic hard film such as silicon dioxide is formed by sputtering on substantially the entire surface of the magnetic core substrate 13 on which the metal magnetic film is formed. Next, a resist material is uniformly applied to the non-magnetic hard film with a uniform thickness and a semiconductor mask on which a gap pattern is applied is used to correspond to the gap portion of the servo band portion DC erase head and the servo signal recording head. A Gap pattern is aligned on the base glass 8 and exposed to light. Then, the magnetic core substrate 13 is immersed in a developing solution for a predetermined time, and unnecessary resists according to the mask are dissolved and removed, leaving only the necessary shapes. Next, the unnecessary non-magnetic hard film exposed from the remaining resist is removed using reactive ion etching or ion etching, and the resist column of the remaining gap part is washed away with a solvent. Gap portions 4c and 4d are obtained on the base glass. Further, in this gap formation step, the base glass 8 at a position where no gap is formed is formed of a nonmagnetic material 7b for joining the magnetic cores (5a and 5b) of both the servo band portion DC erasing head Ha and the servo signal recording head Hb. Become.

Next, the metal magnetic film 4 having a high saturation magnetic flux density is formed on the metal magnetic film forming surface 12 by any one of a sputtering method, a vapor deposition method, and a plasma CVD method. Thereafter, heat treatment is performed on the magnetic core substrate 13 to obtain good soft magnetic properties for the metal magnetic film 4.
(Step S23) Next, as shown in FIG. 21, on the nonmagnetic material 7b that joins both magnetic cores so that the metal magnetic films of the servo band portion DC erasing head and the servo signal recording head do not interfere magnetically. After the metal magnetic film is removed by the dividing groove 13a, the nonmagnetic material 7c is filled into the dividing groove so as to slightly protrude from the metal magnetic film 4. Thereafter, a shoulder drop groove 13b having an inclination is formed for the purpose of allowing the magnetic tape to smoothly enter the sliding surface when the magnetic head is formed.

  Further, since the metal magnetic film 4 formed in step S22 is formed in a shape along the surface shape of the magnetic core substrate 13, when the substrate 13 is viewed as a whole, only the gaps 4c and 4d are just above the gap. The metal magnetic film protrudes by the height of the portions 4c and 4d. Further, the nonmagnetic material 7c filled in the dividing groove 13a in step S23 is also slightly protruded from the metal magnetic film. In this state, when the magnetic tape runs on the metal magnetic film, a spacing loss is generated when the signal is recorded. Therefore, the protruding portion is removed by buffing or lens polishing as shown in FIG. And evenly cut the entire surface. Thus, the metal magnetic films 4a and 4b and the nonmagnetic material 7c are completed.

Next, as shown in FIG. 23, the magnetic core substrate 13 is reversed to form the winding groove 6 on the main surface opposite to the metal magnetic film forming surface (tape sliding surface), and then the winding grooves 6 other than the main surface are not included. The lens 14 is polished until the nonmagnetic material 7b is exposed at the bonding surface. In addition, since a metal film for bonding is formed in a subsequent process, the surface roughness Ra of the bonding surface 14 is desirably 10 nm or less. Further, the flatness (undulation of the unevenness) of the surface is preferably 100 nm or less from one end to the other end in the magnetic tape running direction and the width direction.
(Step S24) A vapor deposition film of a metal film is formed on the bonding surface 14 of the magnetic core substrate 13 as shown in FIG. Here, the metal film preferably has a two-layer structure, and the first metal film 15a is for ensuring adhesion between the magnetic core substrate 13 and the second metal film 15b. It is a thin film made of Cr or Ti having a thickness of about 50 nm. The second metal film 15b is a metal thin film that can be diffusion bonded at a temperature below the glass transition point of the hard non-magnetic material, and has a uniform thickness of, for example, 10 to 200 nm, preferably 10 to 100 nm. It is a deposited film such as Au.
(Step S25) As shown in FIG. 25, the servo band portion DC erasing head Ha and the servo signal are formed on the bonding surface 17a of the magnetic core substrate 16 which is the original plate of the plurality of magnetic core halves 10 to be bonded to the magnetic core substrate 13. A groove corresponding to the position of the nonmagnetic material 7a for joining the magnetic cores (10a and 10b) of the recording head Hb is formed, and after filling the groove with a hard nonmagnetic material, the protruding hard nonmagnetic material is polished. To smooth the joining surface 17a.
(Step S26) Next, as shown in FIG. 26, with respect to the main surface 17b opposite to the bonding surface 17a of the magnetic core substrate 16, the flatness of the surface is from one end to the other end in the recording medium width direction. Polishing is performed until the nonmagnetic material 7a is exposed to the main surface 17b so as to be 100 nm or less, and then the winding groove 9 corresponding to the magnetic core half body 10 is formed on the bonding surface 17a. Thereafter, the bonding surface 17a is finished flat by lens polishing or the like. In addition, since a metal film for bonding is formed in a subsequent process, the surface roughness Ra of the bonding surface 17a is desirably 10 nm or less. The flatness of the surface is preferably 100 nm or less from one end to the other end in the recording medium running direction L and the recording medium width direction W.
(Step S27) Next, as shown in FIG. 27, the first metal film 15a / second metal film 15b deposited film similar to step S14 is formed on the bonding surface 17a of the magnetic core substrate 16.
(Step S28) Using the magnetic core substrate 13 after step S24 and the magnetic core substrate 16 after step S16, the bonding surface 14 of the magnetic core substrate 13 and the bonding surface 17a of the magnetic core substrate 16 face each other. After aligning the winding groove 6 of the magnetic core substrate 13 and the winding groove 9 of the magnetic core substrate 16 as described above, the second metal films 15b are brought into contact with each other to perform low-temperature metal diffusion bonding.

Here, the low temperature metal diffusion bonding refers to the second metal film 15b provided on the bonding surface 14 of the magnetic core substrate 13 and the second metal film 15b provided on the bonding surface 17a of the magnetic core substrate 16 described above. The constituent atoms of the second metal film 15b are mutually diffused and bonded at a temperature not higher than the glass transition point of the hard nonmagnetic material. Specifically, in the case of the second metal film 15b made of Au, a heating temperature of 150 to 300 ° C. and a processing time of several minutes to several hours in a state where both the second metal films 15b are brought into contact with each other with a pressure of about 10 to 20 MPa. Bonding is possible by this heat treatment.
(Step S29) Finally, as shown in FIG. 29, the combined substrate in which the magnetic core substrate 13 and the magnetic core substrate 16 are joined is cut at the cutting position aa ′, and the magnets for each row constituting the magnetic core are cut. Get the core block.

  Thereafter, a conductive wire is wound around the winding groove of the obtained magnetic core to form an exciting coil, thereby completing the magnetic head shown in FIG.

Next, a second example of the method of manufacturing the magnetic head (FIG. 17) of this embodiment will be described step by step with reference to FIGS. 19 and 30 to 34.
(Step S31) First, as shown in FIG. 19, on one main surface of the magnetic core substrate 13 which is the original plate of the plurality of magnetic core halves 5, the servo band portion DC erasing head, the gap portion of the servo signal recording head, and both A groove corresponding to the position of the nonmagnetic material for joining the magnetic core is formed, and the hard nonmagnetic material is filled and fused in the groove, and the protruding hard nonmagnetic material is polished to polish the base glass 8. Form. At the same time, polishing is performed so that the metal magnetic film forming surface 12 including the base glass 8 becomes flat. Further, the flatness (undulation of the unevenness) of the surface is preferably 100 nm or less from one end to the other end in the magnetic tape running direction and the width direction.
(Step S32) Next, as shown in FIG. 30, the gaps 4c and 4d and the metal magnetic films of the servo band part DC erasing head and the servo signal recording head are divided on the metal magnetic film forming surface of the magnetic core substrate 13. A nonmagnetic material 7c is formed.

  Specifically, first, a nonmagnetic hard film such as silicon dioxide is formed by sputtering on substantially the entire surface of the magnetic core substrate 13 on which the metal magnetic film is formed. Next, a non-magnetic material (7c) that uniformly coats the non-magnetic hard film with a uniform thickness and divides the Gap pattern and the metal magnetic films of the servo band portion DC erasing head and the servo signal recording head. The base glass 8 corresponding to the gap part of the servo band part DC erasing head and the servo signal recording head, and the magnetic cores of both the servo band part DC erasing head and the servo signal recording head using the semiconductor mask having the pattern On the base glass 8 corresponding to the nonmagnetic material (7b) for bonding the film, the Gap pattern and the pattern of the nonmagnetic material (7c) for dividing the metal magnetic film are aligned and exposed to light. Then, the magnetic core substrate 13 is immersed in a developing solution for a predetermined time, and unnecessary resists according to the mask are dissolved and removed, leaving only the necessary shapes. Next, the reactive non-magnetic hard film exposed from the remaining resist is removed using reactive ion etching or ion etching, and then the remaining gap part and the non-magnetic material part resist for dividing the metal magnetic film are separated. By washing away the resist with a solvent, the gap portions 4c and 4d and the nonmagnetic material 7c are obtained on the base glass. In this step, the base glass 8 at the position of the nonmagnetic material 7b becomes the nonmagnetic material 7b for joining the magnetic cores of both the servo band portion DC erasing head and the servo signal recording head.

Next, as shown in FIG. 31, a metal magnetic film 4 having a high saturation magnetic flux density is formed on the metal magnetic film forming surface 12 by any one of a sputtering method, a vapor deposition method, and a plasma CVD method. Thereafter, heat treatment is performed on the magnetic core substrate 13 to obtain good soft magnetic properties for the metal magnetic film 4.
(Step S33) Next, since the metal magnetic film formed in Step S32 is formed along the surface shape of the magnetic core substrate 13, the gap portions 4c, 4d, and The metal magnetic film protrudes immediately above the nonmagnetic material 7c. In this state, when a magnetic tape runs on the metal magnetic film, a spacing loss is generated by the amount of protrusion when recording a signal. Therefore, as shown in FIG. 32, the protrusion is formed by buff polishing or lens polishing. Remove and evenly cut the entire surface. Thus, the metal magnetic films 4a and 4b and the nonmagnetic material 7b are completed. Thereafter, as shown in FIG. 33, a shoulder drop groove 13b having an inclination is formed for the purpose of allowing the magnetic tape to smoothly enter the sliding surface in the case of a magnetic head.

  Next, as shown in FIG. 34, the magnetic core substrate 13 is reversed to form the winding groove 6 on the main surface opposite to the metal magnetic film forming surface (tape sliding surface), and then the winding grooves 6 other than the main surface are not included. The lens 14 is polished until the nonmagnetic material 7b is exposed at the bonding surface. In addition, since a metal film for bonding is formed in a subsequent process, the surface roughness Ra of the bonding surface 14 is desirably 10 nm or less. Further, the flatness (undulation of the unevenness) of the surface is preferably 100 nm or less from one end to the other end in the magnetic tape running direction and the width direction.

  Since the subsequent steps are the same as steps S24 to S29 in the first example of the magnetic head manufacturing method of the present invention, the description thereof will be omitted.

As described above, the metal magnetic film serving as the sliding surface of the DC erasing magnetic head and the metal magnetic film serving as the sliding surface of the servo signal recording magnetic head are separated by the nonmagnetic material by the manufacturing method of this embodiment. A DC-erased head and servo signal recording head integrated magnetic head can be realized. Since the magnetic head (FIG. 17) in this embodiment does not have a dividing groove (13a) in which magnetic powder falling off from the magnetic layer is deposited when the magnetic tape travels, the magnetic tape as shown in FIG. Since no erasure signal and servo signal can be recorded with a sufficient recording magnetic field applied to the magnetic tape, the reproduction output does not decrease during servo signal reproduction. Further, the head clog as shown in FIG. 16 does not occur, and there is no problem that the servo signal cannot be recorded by the head clog. This makes it possible to record the DC erasure signal and the servo signal stably. After performing the DC erasure on the servo band portion of the running recording medium, the servo signal is generated by the magnetic field in the direction opposite to the DC erasure. In the recording method, a DC erase head / servo signal recording head integrated magnetic head capable of stably obtaining a high reproduction output during servo signal reproduction can be realized.
(Example 2)
Hereinafter, an example in which the magnetic head according to this embodiment is actually manufactured will be described.

In accordance with the magnetic head manufacturing method described above, a magnetic head for 1/2 inch width magnetic tape was manufactured under the following conditions.
(1) Metal magnetic film 4; Fe-Ta microcrystalline film Thickness: 3 μm
(2) Magnetic cores 5 and 10; ferrite substrate (dimensions 30 × 30 × 1.5 mm)
(3) Hard non-magnetic material; glass transition temperature 550 ° C
(4) Metal magnetic film heat treatment temperature: 480 ° C
(5) Non-magnetic material for metal magnetic film separation: silicon dioxide Using the magnetic head manufactured under the above conditions, DC erase signal and servo signal are recorded on 1/2 inch width magnetic tape for LTO format. As a result of reproducing and evaluating the servo signal with two drives, it was confirmed that the reproduction output during the servo signal reproduction did not decrease and the problem that the servo signal was not recorded did not occur.
(Comparative example)
Under the same conditions as in the example, a DC head erase signal and servo signal were recorded on a 1/2 inch width magnetic tape for LTO format using a magnetic head that was cut only by metal magnetic film in the groove. As a result of reproducing and evaluating the servo signal with the drive, it was confirmed that there was a decrease in reproduction output during servo signal reproduction and the problem that the servo signal was not recorded.

  Next, another embodiment of the present invention will be described. In the magnetic heads of FIGS. 1 and 17, since the servo band portion DC erasing head Ha and the servo signal recording head Hb are close to each other, the servo signal leaked from the servo signal recording head magnetic core when recording the servo signal. The magnetic field enters the DC erasing head magnetic core, interferes with the DC erasing magnetic field in the DC erasing head magnetic core, and stable DC erasing cannot be performed, resulting in a variation in reproduction output during servo signal reproduction.

  In order to solve this problem, as a means for avoiding magnetic interference between two magnetic heads close to each other, a method of arranging a conductive nonmagnetic metal material grounded between the two magnetic heads Is generally used, the nonmagnetic material 7b disposed between the DC erasing head Ha of FIGS. 1 and 17 and the servo signal recording head Hb is replaced with a conductive nonmagnetic metal material such as Cu or Au. The magnetic head was manufactured using the DC erase head and the magnetic core of the DC erase head and the servo signal recording head (magnetic core substrate 13, magnetic core half body) in the step of performing the heat treatment in the head manufacturing process. 35a and 5b) and the stress generated by the difference in coefficient of thermal expansion between the conductive nonmagnetic material and the ferrite material forming the magnetic core are frequently cracked as shown in FIG. Is big Problem occurs to decrease to.

  In the present embodiment, in order to solve the above problem, the magnetic head is configured as shown in FIG. In this configuration example, a magnetic core half 5a for a DC erasing head having a metal magnetic film 4a on the surface serving as a sliding surface with the recording medium and constituting a magnetic path of a DC erasing signal, and a sliding surface with the recording medium And a front core 1 in which a servo signal recording head magnetic core half 5b having a metal magnetic film 4b constituting a servo signal magnetic path on the surface is joined and integrated via a nonmagnetic material 7b, and a winding groove A magnetic core half 10a for DC erasing head having 9a and a back core 2 in which a magnetic core half 10b for servo signal recording head having a winding groove 9b is joined and integrated through a nonmagnetic material 7a. And a DC erasing / servo-recording integrated magnetic core joined by the joining portion 3 and an exciting coil (not shown) in which a conducting wire is wound around the winding grooves 9a and 9b of the magnetic core.

  Further, a conductive nonmagnetic thin film material 7b1 is provided between the magnetic core half 5a for the DC erase head and the nonmagnetic material 7b, and a conductive property is provided between the magnetic core half 5b for the servo signal recording head and the nonmagnetic material 7b. A nonmagnetic thin film material 7b2 is disposed. Further, a conductive nonmagnetic thin film material 7a1 is provided between the magnetic core half 10a for the DC erase head and the nonmagnetic material 7a, and a conductive property is provided between the magnetic core half 10b for the servo signal recording head and the nonmagnetic material 7a. A nonmagnetic thin film material 7a2 is provided. In addition, the conductive nonmagnetic thin film materials 7a1, 7a2, 7b1, and 7b2 are electrically connected at the joint 3, and conductive paste (not shown) is formed from the conductive nonmagnetic materials 7a1 and 7a2 exposed from the side surface of the head. Etc.) is grounded.

  Here, the metal magnetic films 4a and 4b are Fe-based microcrystalline films, Fe-Ta-based microcrystalline films, Fe-Al-Si-based films, or other soft magnetic materials having a high saturation magnetic flux density similar to this, such as NiFe. A film made of an alloy is formed with a thickness of several μm. Gap 4c and 4d are writing patterns made of a non-magnetic material that is formed on the base glasses 8a and 8b and has a height that reaches the sliding surface of the recording medium so as to divide the metal magnetic films 4a and 4b. When recording on the recording medium, the gap patterns 4c and 4d prevent the magnetic flux generated when a current flows through the exciting coil, so that the gap pattern can be recorded on the traveling recording medium.

  The material constituting the magnetic core halves 5a, 5b, 10a, 10b is a conventionally known magnetic material, and may be either single crystal ferrite or polycrystalline ferrite. For example, Mn—Zn ferrite and the like can be mentioned.

  The magnetic core halves 5a and 5b constituting the front core 1 have grooves extending in the width direction W of the magnetic recording medium immediately below the gaps 4c and 4d of the metal magnetic films 4a and 4b, and hard nonmagnetic materials are further provided in the grooves. The base glass 8a, 8b is filled and fused. The magnetic core halves 5a and 5b are joined and integrated by a hard nonmagnetic material 7b. These hard nonmagnetic materials 7b, 8a, and 8b may be any nonmagnetic material that can be fused to the magnetic core halves 5a and 5b to ensure a certain level of strength. For example, in consideration of the heat treatment temperature of the metal magnetic film, it is preferable to use refractory glass having a glass transition temperature higher than the heat treatment temperature of the metal magnetic film. Moreover, the magnetic core halves 5a and 5b have winding grooves 6a and 6b that are open on the side opposite to the surface on which the metal magnetic films 4a and 4b are formed.

  In addition, the metal magnetic film forming surface 12 shown in FIG. 37 (cross-sectional view of the front core 1) is provided with the magnetic core halves 5a and 5b, the conductive nonmagnetic thin film before the metal magnetic films 4a and 4b are formed. In a state where the materials 7b1 and 7b2, the nonmagnetic material 7b, and the base glasses 8a and 8b are integrated, a flat mirror finish without a step is applied using a lens polishing apparatus or the like. Magnetic gaps 4c, 4d are formed by photolithography using a semiconductor mask in which a DC erase signal gap pattern and a servo signal gap pattern are arranged with high precision on the mirror-finished metal magnetic film forming surface 12. Are simultaneously formed, and then the metal magnetic films 4a and 4b are formed simultaneously.

  The conductive nonmagnetic thin film materials 7a1, 7a2, 7b1, and 7b2 are formed by plating, vapor deposition, sputtering, or the like, so that Au, Ag, Cu, Pt, Cr, Ti, or the like is used. Is preferred. Further, these nonmagnetic thin film materials may be stacked on each other. Furthermore, the thickness of the conductive nonmagnetic thin film material should be 5 μm or less in order to reduce the influence of the stress generated by the difference in thermal expansion coefficient between the conductive nonmagnetic thin film material and the ferrite material forming the magnetic core. Is preferred.

  With the above configuration, the magnetic head of the present invention can be applied to the magnetic core of the servo signal magnetic field DC erasure head by the conductive nonmagnetic thin film material disposed at the junction between the DC erasure magnetic head and the servo signal recording magnetic head. Therefore, stable DC erasure can be performed, and variations in reproduction output during servo signal reproduction can be reduced. In addition, by setting the thickness of the conductive nonmagnetic thin film material to 5 μm or less, it is possible to reduce the influence of stress generated by the difference in thermal expansion coefficient between the ferrite material forming the magnetic core and the conductive nonmagnetic material. Cracks do not occur in the ferrite material that forms the magnetic core, and there is no significant drop in yield due to cracks.

Next, a method of manufacturing the magnetic head (FIG. 36) according to this embodiment will be described step by step with reference to FIGS.
(Step S41) First, as shown in FIG. 38, the magnetic cores of both the servo band portion DC erasing head and the servo signal recording head are formed on one main surface of the magnetic core substrate 13 which is the original plate of the plurality of magnetic core halves 5. After forming the groove 7 corresponding to the position of the nonmagnetic material to be joined, the conductive nonmagnetic thin film material 7bb is formed on the inner surface of the groove by any of plating, vapor deposition, and sputtering.
(Step S42) Next, as shown in FIG. 39, on one main surface of the magnetic core substrate 13 which is the original plate of the plurality of magnetic core halves 5, the positions of the servo band portion DC erasing head and the gap portion of the servo signal recording head After forming the groove 8 corresponding to the groove 7 and the groove 7 formed with the conductive nonmagnetic thin film material 7bb, the hard nonmagnetic material is filled and fused, and the hard nonmagnetic material protruding at this time, Then, the conductive nonmagnetic thin film material 7bb on the main surface is polished to form the nonmagnetic material 7b and the base glasses 8a and 8b. At the same time, polishing is performed so that the metal magnetic film forming surface 12 including the base glass becomes flat. Further, the flatness (undulation of the unevenness) of the surface is preferably 100 nm or less from one end portion to the other end portion in the magnetic tape running direction and the width direction.
(Step S43) Next, as shown in FIG. 40, the metal magnetic film 4 and the gap portions 4c and 4d are formed on the metal magnetic film formation surface of the magnetic core substrate 13. Specifically, first, a nonmagnetic hard film such as silicon dioxide is formed by sputtering on substantially the entire surface of the magnetic core substrate 13 on which the metal magnetic film is formed. Next, a resist material is uniformly applied to the non-magnetic hard film with a uniform thickness and a semiconductor mask on which a gap pattern is applied is used to correspond to the gap portion of the servo band portion DC erase head and the servo signal recording head. Gap patterns are aligned on the base glasses 8a and 8b, and exposure is performed by applying light. Then, the magnetic core substrate 13 is immersed in a developing solution for a predetermined time, and unnecessary resists according to the mask are dissolved and removed, leaving only the necessary shapes. Next, the unnecessary non-magnetic hard film exposed from the remaining resist is removed using reactive ion etching or ion etching, and the resist column of the remaining gap part is washed away with a solvent. Gap portions 4c and 4d are obtained on the base glass.

Next, the metal magnetic film 4 having a high saturation magnetic flux density is formed on the metal magnetic film forming surface 12 by any one of a sputtering method, a vapor deposition method, and a plasma CVD method. Thereafter, heat treatment is performed on the magnetic core substrate 13 to obtain good soft magnetic properties for the metal magnetic film 4.
(Step S44) Next, as shown in FIG. 41, on the nonmagnetic material 7b that joins both magnetic cores so that the metal magnetic films of both the servo band portion DC erasing head and the servo signal recording head do not interfere magnetically. After removing the metal magnetic film at the dividing groove 13a, a shoulder dropping groove 13b having an inclination is formed for the purpose of allowing the magnetic tape to smoothly enter the sliding surface when the magnetic head is formed.

Further, since the metal magnetic film formed in step S43 is formed in a shape along the surface shape of the magnetic core substrate 13, when the entire substrate 13 is viewed, only the gap portions 4c, 4d are just above the gap portions. The metal magnetic film protrudes by the height of 4c and 4d. In this state, when the magnetic tape runs on the metal magnetic film, a spacing loss occurs when the signal is recorded. Therefore, the protrusion is removed by buffing or lens polishing, and the entire surface is removed. Sharpen evenly. Thus, the metal magnetic films 4a and 4b are completed.
(Step S45) Next, the magnetic core substrate 13 is inverted, and the winding groove 6 is formed on the main surface opposite to the metal magnetic film forming surface (tape sliding surface) as shown in FIG. The joining surface 14 which is a region other than the winding groove 6 is subjected to lens polishing until the nonmagnetic material 7b is exposed at the joining surface. By this polishing operation, the conductive nonmagnetic thin film material 7bb formed on the inner surface of the groove is divided into 7b1 and 7b2, respectively. In addition, since a metal film for bonding is formed in a subsequent process, the surface roughness Ra of the bonding surface 14 is desirably 10 nm or less. Further, the flatness (undulation of the unevenness) of the surface is preferably 100 nm or less from one end to the other end in the magnetic tape running direction and the width direction.
(Step S46) A vapor deposition film of a metal film is formed on the bonding surface 14 of the magnetic core substrate 13 (FIG. 43). Here, when the metal film comes into contact with the conductive nonmagnetic thin film materials 7b1 and 7b2 and becomes electrically conductive, when the DC erase signal and the servo signal are recorded, the metal film causes the DC erase head magnetic core 5a, Since the flow of the DC erasing magnetic field in 10a and the flow of the servo signal magnetic field in the servo signal recording head magnetic cores 5b and 10b are hindered, masking or the like is performed when forming the metal film, as shown in FIG. It is preferable that the upper metal film is not in contact with the conductive nonmagnetic thin film materials 7b1 and 7b2. The metal film preferably has a two-layer structure, and the first metal film 15a is for ensuring the adhesion between the magnetic core substrate 13 and the second metal film 15b. It is a thin film made of Cr or Ti having a thickness of about 50 nm. The second metal film 15b is a metal thin film that can be diffusion bonded at a temperature below the glass transition point of the hard non-magnetic material, and has a uniform thickness of, for example, 10 to 200 nm, preferably 10 to 100 nm. It is a deposited film such as Au.
(Step S47) As shown in FIG. 44, the servo band portion DC erasing head Ha and the servo signal are formed on the bonding surface 17a of the magnetic core substrate 16 which is the original plate of the plurality of magnetic core halves 10 and bonded to the magnetic core substrate 13. A groove corresponding to the position of the nonmagnetic material 7a for joining the magnetic cores (10a and 10b) of the recording head Hb is formed, and a conductive nonmagnetic material is formed on the inner surface of the groove by any one of a plating method, a vapor deposition method, and a sputtering method. After the thin film material 7aa is formed, the groove is filled with the hard nonmagnetic material 7a, and the protruding hard nonmagnetic material 7a and the conductive nonmagnetic thin film material 7aa on the bonding surface 17a are polished to smooth the bonding surface 17a. To.
(Step S48) Next, as shown in FIG. 45, with respect to the main surface 17b opposite to the bonding surface 17a of the magnetic core substrate 16, the flatness of the surface is from one end to the other end in the recording medium width direction. Polishing is performed until the nonmagnetic material 7a is exposed to the main surface 17b so as to be 100 nm or less. By this polishing operation, the conductive nonmagnetic thin film material 7aa formed on the inner surface of the groove is divided into 7a1 and 7a2, respectively. Next, a winding groove 9 corresponding to the magnetic core half 10 is formed on the joint surface 17a. Thereafter, the bonding surface 17a is finished flat by lens polishing or the like. In addition, since a metal film for bonding is formed in a subsequent process, the surface roughness Ra of the bonding surface 17a is desirably 10 nm or less. The flatness of the surface is preferably 100 nm or less from one end to the other end in the recording medium running direction L and the recording medium width direction W.
(Step S49) Next, as shown in FIG. 46, the first metal film 15a / second metal film 15b deposited film similar to that in step S46 is formed on the bonding surface 17a of the magnetic core substrate 16. For the same reason as described in step S46, masking or the like is performed when forming the metal film, and the metal film on the magnetic core does not contact the conductive nonmagnetic thin film materials 7a1 and 7a2 as shown in FIG. It is preferable to do so.
(Step S50) Using the magnetic core substrate 13 after step S46 and the magnetic core substrate 16 after step S49, the bonding surface 14 of the magnetic core substrate 13 and the bonding surface 17a of the magnetic core substrate 16 are formed as shown in FIG. After facing each other and aligning the winding groove 6 of the magnetic core substrate 13 and the winding groove 9 of the magnetic core substrate 16, the second metal films 15b are brought into contact with each other to perform low-temperature metal diffusion bonding.

  Here, the low temperature metal diffusion bonding refers to the second metal film 15b provided on the bonding surface 14 of the magnetic core substrate 13 and the second metal film 15b provided on the bonding surface 17a of the magnetic core substrate 16 described above. The constituent atoms of the second metal film 15b are mutually diffused and bonded at a temperature not higher than the glass transition point of the hard nonmagnetic material. Specifically, in the case of the second metal film 15b made of Au, a heating temperature of 150 to 300 ° C. and a processing time of several minutes to several hours in a state where both the second metal films 15b are brought into contact with each other with a pressure of about 10 to 20 MPa. Bonding is possible by this heat treatment.

Further, in the main bonding step, the conductive nonmagnetic thin film materials 7a1, 7a2, 7b1, and 7b2 are electrically connected through the metal film at the bonding portion.
(Step S51) Finally, as shown in FIG. 48, the combined substrate in which the magnetic core substrate 13 and the magnetic core substrate 16 are joined is cut at the cutting position aa ′, and the magnets for each row constituting the magnetic core are cut. Get the core block.

  Thereafter, a conductive wire is wound around the winding groove of the obtained magnetic core to form an exciting coil, and the conductive nonmagnetic thin film materials 7a1 and 7a2 exposed on the side surface of the magnetic head are grounded with a conductive paste or the like, whereby FIG. To complete the magnetic head.

  As described above, the DC erase head servo signal in which the junction between the DC erase magnetic head Ha and the servo signal recording magnetic head Hb is magnetically cut off by the conductive nonmagnetic thin film material by the manufacturing method of this embodiment. A recording head integrated magnetic head can be realized.

  Note that the conductive nonmagnetic thin film materials 7a1, 7a2, 7b1, and 7b2 in this embodiment may be provided in the magnetic head of FIG. 17 having the nonmagnetic material 7c. In that case, the same operations and effects as described above can be achieved.

  In the magnetic head of the present embodiment, the leakage magnetic field from the servo signal recording head magnetic core that occurs when recording the servo signal enters the DC erasing head magnetic core. Since it is blocked by the conductive non-magnetic thin film material disposed at the joint of the magnetic head for the magnetic head, stable direct current erasure can be performed.

  In addition, by setting the thickness of the conductive nonmagnetic thin film material to 5 μm or less, it is possible to reduce the influence of the stress caused by the difference in thermal expansion coefficient from the ferrite material that forms the magnetic core, so the ferrite material that forms the magnetic core Cracks do not occur, and the yield does not drop significantly due to cracks.

As a result, there is no variation in reproduction output during servo signal reproduction in a system in which servo signals are recorded by a magnetic field in the opposite direction to the direct current erasure after performing direct current erasure on the servo band portion of the recording medium that is running. A magnetic head integrated with a DC erasing head and servo signal recording head can be realized with a stable yield.
(Example 3)
Hereinafter, an example in which the magnetic head according to this embodiment is actually manufactured will be described.

In accordance with the magnetic head manufacturing method described above, a magnetic head for 1/2 inch width magnetic tape was manufactured under the following conditions.
(1) Metal magnetic film 4; Fe-Ta microcrystalline film Thickness: 3 μm
(2) Magnetic cores 5 and 10; ferrite substrate (dimensions 30 × 30 × 1.5 mm)
(3) Conductive nonmagnetic thin film material: Ti—Cu—Cr laminated film, thickness 2 μm (Cu is formed by plating, Ti and Cr are formed by vapor deposition)
(4) Hard non-magnetic material: high melting point glass (glass transition temperature 550 ° C.)
(5) Hard non-magnetic material filling temperature: 800 ° C
(6) Metal magnetic film heat treatment temperature: 480 ° C
(7) Low temperature metal diffusion bonding temperature: 300 ° C
Using the magnetic head manufactured under the above conditions, the DC erase signal and servo signal were recorded on the 1/2 inch width magnetic tape for LTO format, and the servo signal was reproduced and evaluated by the LTO-2 drive. It was confirmed that the variation in reproduction output during signal reproduction was 0.3 dB or less as in Table 1.

Further, in this head manufacturing method, heat treatment is performed in three steps of filling with a hard non-magnetic material, heat treatment of the metal magnetic film, and joining of the magnetic core substrate 13 and the magnetic core substrate 16. It was confirmed that the ferrite material forming the core did not crack and that there was no decrease in yield.
(Comparative Example-1)
Under the conditions of Example 3, a magnetic head without the conductive nonmagnetic material 7a1, 7a2, 7b1, 7b2 shown in FIG. 36 was prepared, and this magnetic head was used to form a 1/2 inch wide magnetic tape for LTO format. As a result of recording the DC erase signal and the servo signal, reproducing the servo signal with the LTO-2 drive, and evaluating it, a reproduction output variation of 1 to 2 dB was confirmed during the servo signal reproduction.
(Comparative Example-2)
The conductive nonmagnetic materials 7a1, 7a2, 7b1, and 7b2 are not disposed under the conditions of Example 3, and the hard nonmagnetic material in the portions of the nonmagnetic materials 7a and 7b in FIG. 36 is Cu by plating. A magnetic head was manufactured, and this magnetic head was used to record a DC erasure signal and servo signal on a 1 / 2-inch width magnetic tape for LTO format. The servo signal was reproduced and evaluated by the LTO-2 drive. It was confirmed that the variation in reproduction output during signal reproduction was 0.3 dB or less.

However, at the time of heat treatment of the magnetic metal film of the head and at the time of overheating of the bonding between the magnetic core substrate 13 and the magnetic core substrate 16, the ferrite material forming the magnetic core frequently cracks and the head caused by the cracks Cracks also occurred frequently, and the yield dropped significantly.
(Comparative Example-3)
Under the conditions of Example 3, a magnetic head in which the thickness of the conductive non-magnetic material 7a1, 7a2, 7b1, 7b2 was set as shown in Table 3 below was produced, and the cracked and cracked state of the ferrite material forming the magnetic core As a result, it was confirmed that the thickness of the conductive nonmagnetic material is preferably 5 μm or less.

1 is a perspective view of a magnetic head according to an embodiment of the present invention. 1 is a schematic cross-sectional view of a main part of a magnetic head according to an embodiment of the invention. Explanatory drawing which shows the relationship between the gap for DC erase signal recording in this invention, and the gap for servo signal recording. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of one Embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of one Embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of one Embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of one Embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of one Embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of one Embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of one Embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of one Embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of one Embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of one Embodiment of this invention. 1 is a perspective view of a magnetic head according to an embodiment of the present invention. FIG. 15 is an explanatory diagram showing problems of the magnetic head of FIG. 14. FIG. 15 is an explanatory diagram showing problems of the magnetic head of FIG. 14. The perspective view of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic of the magnetic head of the other embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows the other example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows the other example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows the other example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows the other example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part perspective view which shows the other example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. FIG. 2 is an explanatory diagram showing problems of the magnetic head in FIG. 1. The perspective view of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic of the magnetic head of the other embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part explanatory drawing which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part perspective view which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. The principal part cross-sectional schematic diagram which shows an example of the manufacturing process of the manufacturing method of the magnetic head of the other embodiment of this invention. Explanatory drawing which shows an example of the recording pattern of the magnetic tape which concerns on this invention. The block diagram which shows an example of the conventional servo signal recording device. Explanatory drawing showing the problem of the conventional servo signal recording method. The block diagram which shows an example of the conventional DC erase and servo signal recording. Explanatory drawing showing the problem of the conventional DC erase and servo signal recording. Explanatory drawing showing the problem of the magnetic head which performs the conventional DC erase and servo signal recording.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Front core, 2 ... Back core, 3 ... Joint part, 4a, 4b ... Metal magnetic film, 4c, 4d ... Gap part, 5a, 5b, 10a, 10b ... Half magnetic core, 6a, 6b, 9a, 9b ... winding groove, 7a, 7b, 7c ... nonmagnetic material, 7aa, 7a1, 7a2, 7bb, 7b1, 7b2 ... conductive nonmagnetic thin film material, 8a, 8b ... base glass, 12 ... metal magnetic film forming surface, 13 , 16 ... magnetic core substrate, 13a ... dividing groove, 15a ... first metal film, 15b ... second metal film, Ha ... DC erasing magnetic head, Hb ... DC erasing magnetic head.

Claims (10)

In a magnetic head used for a magnetic recording medium having a data signal recording portion and a servo signal recording portion in a magnetic layer,
A magnetic magnetic film on the surface serving as a sliding surface with the magnetic recording medium, and a sliding surface between the magnetic recording medium and a DC erasing magnetic head for performing DC erasing on the servo signal recording unit A servo signal recording magnetic head having a metal magnetic film on the surface and recording a servo signal in the signal recording area of the servo signal recording unit by a magnetic field in the direction opposite to the direct current erasing is closely integrated. ,
The magnetic head of the DC erasing magnetic head and the magnetic magnetic film forming surface of the servo signal recording magnetic head are formed in the same plane.   Between the metal magnetic film of the DC erasing magnetic head and the metal magnetic film of the servo signal recording magnetic head, a sliding surface of the metal magnetic film of the DC erasing magnetic head with the magnetic recording medium is provided. A non-magnetic material having a sliding surface with the magnetic recording medium formed in the same plane as the sliding surface with the magnetic recording medium of the metal magnetic film of the magnetic head for servo signal recording is interposed. The magnetic head according to claim 1.   2. The magnetic head according to claim 1, wherein a conductive nonmagnetic thin film material is interposed between the DC erasing magnetic head and the servo signal recording magnetic head.   3. The magnetic head according to claim 2, wherein a conductive nonmagnetic thin film material is interposed between the DC erasing magnetic head and the servo signal recording magnetic head.   The magnetic head according to claim 3, wherein the thickness of the conductive nonmagnetic thin film material is 5 μm or less.   5. The magnetic head according to claim 4, wherein the thickness of the conductive nonmagnetic thin film material is 5 [mu] m or less. In a method for manufacturing a magnetic head used in a magnetic recording medium having a data signal recording portion and a servo signal recording portion in a magnetic layer,
Forming a plurality of grooves having a predetermined depth at a predetermined interval on one surface of the first magnetic core substrate, and filling each of the grooves with a first nonmagnetic material;
A gap of a DC erasing magnetic head and a servo signal recording magnetic head are formed on a pair of first nonmagnetic materials adjacent to one first nonmagnetic material among the plurality of first nonmagnetic materials. Each forming step;
Forming a metal magnetic film on one surface of the first magnetic core substrate including the two gaps and the first nonmagnetic material;
Removing a metal magnetic film on the one first nonmagnetic material located between the pair of nonmagnetic materials;
Polishing the other surface of the first magnetic core substrate until the first nonmagnetic material is exposed, and then forming a bonding metal film on the surface;
Forming a groove having a predetermined depth on one surface of the second magnetic core substrate, and filling the groove with a second nonmagnetic material;
Polishing the other surface of the second magnetic core substrate until the second nonmagnetic material is exposed, and then forming a bonding metal film on the surface;
A method of manufacturing a magnetic head, comprising: bonding a metal film for bonding the first magnetic core substrate and a metal film for bonding the second magnetic core substrate. In a method for manufacturing a magnetic head used in a magnetic recording medium having a data signal recording portion and a servo signal recording portion in a magnetic layer,
Forming a plurality of grooves having a predetermined depth at a predetermined interval on one surface of the first magnetic core substrate, and filling each of the grooves with a first nonmagnetic material;
A gap of a DC erasing magnetic head and a servo signal recording magnetic head are formed on a pair of first nonmagnetic materials adjacent to one first nonmagnetic material among the plurality of first nonmagnetic materials. Each forming step;
Forming a metal magnetic film on one surface of the first magnetic core substrate including the two gaps and the first nonmagnetic material;
Removing a metal magnetic film on the one first nonmagnetic material located between the pair of nonmagnetic materials;
Filling the second non-magnetic material onto the first non-magnetic material from which the metal magnetic film has been removed;
Polishing the other surface of the first magnetic core substrate until the first nonmagnetic material is exposed, and then forming a bonding metal film on the surface;
Forming a groove having a predetermined depth on one surface of the second magnetic core substrate, and filling the groove with a third nonmagnetic material;
Polishing the other surface of the second magnetic core substrate until the third nonmagnetic material is exposed, and then forming a bonding metal film on the surface;
A method of manufacturing a magnetic head, comprising: bonding a metal film for bonding the first magnetic core substrate and a metal film for bonding the second magnetic core substrate. In a method for manufacturing a magnetic head used in a magnetic recording medium having a data signal recording portion and a servo signal recording portion in a magnetic layer,
Forming a plurality of grooves having a predetermined depth at a predetermined interval on one surface of the first magnetic core substrate, and filling each of the grooves with a first nonmagnetic material;
A gap of a DC erasing magnetic head and a servo signal recording magnetic head are formed on a pair of first nonmagnetic materials adjacent to one first nonmagnetic material among the plurality of first nonmagnetic materials. Forming each and forming a second non-magnetic material on said one first non-magnetic material;
Forming a metal magnetic film on one surface of the first magnetic core substrate including the two gaps, the first nonmagnetic material and the second nonmagnetic material;
Uniformly polishing one surface of the first magnetic core substrate on which the metal magnetic film is formed;
Polishing the other surface of the first magnetic core substrate until the first nonmagnetic material is exposed, and then forming a bonding metal film on the surface;
Forming a groove having a predetermined depth on one surface of the second magnetic core substrate, and filling the groove with a third nonmagnetic material;
Polishing the other surface of the second magnetic core substrate until the third nonmagnetic material is exposed, and then forming a bonding metal film on the surface;
A method of manufacturing a magnetic head, comprising: bonding a metal film for bonding the first magnetic core substrate and a metal film for bonding the second magnetic core substrate. In a method for manufacturing a magnetic head used in a magnetic recording medium having a data signal recording portion and a servo signal recording portion in a magnetic layer,
Forming a first groove having a predetermined depth on one surface of the first magnetic core substrate, and forming a first conductive nonmagnetic thin film material on the inner surface of the groove;
A pair of second grooves are formed in a portion of one surface of the first magnetic core substrate adjacent to the first groove at a predetermined interval, and the pair of second grooves and the first conductivity are formed. Filling each nonmagnetic thin film material forming surface with a first nonmagnetic material;
Forming a gap of a magnetic head for DC erasure and a gap of a magnetic head for servo signal recording on the first nonmagnetic material filled in the pair of second grooves;
Forming a metal magnetic film on one surface of the first magnetic core substrate including the two gaps and the first nonmagnetic material;
Removing the metal magnetic film on the first nonmagnetic material of the first groove;
Polishing the other surface of the first magnetic core substrate until the first nonmagnetic material is exposed, and then forming a bonding metal film on the surface;
Forming a third groove having a predetermined depth on one surface of the second magnetic core substrate, and forming a second conductive nonmagnetic thin film material on the inner surface of the groove;
Filling the second conductive nonmagnetic thin film material forming surface with a second nonmagnetic material;
Polishing the other surface of the second magnetic core substrate until the second nonmagnetic material is exposed, and then forming a bonding metal film on the surface;
A method of manufacturing a magnetic head, comprising: bonding a metal film for bonding the first magnetic core substrate and a metal film for bonding the second magnetic core substrate.

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