JP2001331934A - Magnetic recording medium, method for producing the same, magnetic recording and reproducing unit and sputtering target - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of easily producing a magnetic recording medium having excellent magnetic characteristics. SOLUTION: An orientation adjusting film 2 is formed on a surface-textured nonmetallic substrate 1, the surface of the film 2 is oxidized or nitrided and a nonmagnetic base film 3 and a magnetic film 4 are formed on the film 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording medium used for a magnetic disk drive, a method for manufacturing the same, a sputtering target used for manufacturing the magnetic recording medium, and magnetic recording / reproducing using the magnetic recording medium. It concerns the device.

[0002]

2. Description of the Related Art Conventionally, substrates for magnetic recording media include:
A metal substrate made of an aluminum alloy or the like is often used. The metal substrate is usually used after its surface is textured. Texture processing is processing to form irregularities along a predetermined direction (usually the circumferential direction) on the substrate surface. By performing texture processing, the crystal orientation of the underlayer film and the magnetic film formed on the substrate is improved. Then, the magnetic film is given magnetic anisotropy to improve magnetic characteristics such as thermal fluctuation resistance and resolution. By the way, in recent years, as a substrate for a magnetic recording medium, a nonmetallic substrate made of glass, ceramics, or the like has been often used instead of a metal substrate made of aluminum or the like. The non-metallic substrate has an advantage that head slap hardly occurs because of high hardness. However, in the case of a non-metallic substrate such as a glass substrate, it is difficult to provide a magnetic film with sufficient magnetic anisotropy even when texture processing is performed, and the magnetic characteristics of a magnetic recording medium may be insufficient.

For this reason, it has been proposed to form a hard film that can be easily textured on a nonmetallic substrate made of glass, ceramics, or the like. For example, JP-A-5-19
No. 7941 proposes a non-metal substrate having a NiP film, which is a hard film that can be easily textured, formed by a sputtering method. Also, JP-A-4-2956
No. 1 and JP-A-9-167337,
There is disclosed a magnetic recording medium in which a plating film such as an electroless plating film is formed as a hard film on the surface of a nonmetallic substrate. To manufacture a magnetic recording medium having a hard film provided on the surface of a non-metallic substrate, a hard film is formed on a substrate in a film forming apparatus such as a sputtering apparatus, and then the substrate is once carried out of the film forming apparatus and textured. A method of performing texture processing using a processing apparatus, and then carrying it back into the film forming apparatus to form a base film and a magnetic film is adopted.

[0004]

However, in the above-mentioned conventional method for manufacturing a magnetic recording medium, there is a dissatisfaction that the manufacturing process is complicated and the manufacturing cost is increased, and a manufacturing method capable of simplifying the manufacturing process is desired. It had been. The present invention has been made in view of the above circumstances, and has as its object to provide a method capable of easily manufacturing a magnetic recording medium having excellent magnetic properties.

[0005]

According to a method of manufacturing a magnetic recording medium of the present invention, an orientation adjusting film for adjusting the orientation of a film immediately above is formed on a non-metallic substrate having a textured surface,
The surface of the alignment adjusting film is oxidized, and a non-magnetic base film and a magnetic film are formed thereon. The oxidation treatment is preferably performed by bringing the surface of the alignment adjustment film into contact with an oxygen-containing gas. As the oxygen-containing gas,
At least one selected from air, pure oxygen, water vapor, and oxygen-enriched gas can be given. The oxygen-containing gas preferably has an oxygen content of 1 to 100 vol%. A method of manufacturing a magnetic recording medium according to the present invention is characterized in that a surface of an orientation adjusting film is subjected to a nitriding treatment, and a non-magnetic underlayer and a magnetic film are formed thereon. The nitriding treatment is preferably performed by bringing the surface of the alignment adjusting film into contact with a nitrogen-containing gas. As the nitrogen-containing gas, air, pure nitrogen,
At least one selected from nitrogen-enriched gas can be mentioned. The nitrogen content of the nitrogen-containing gas is 1-1.
It is preferably 00 vol%. In the method for manufacturing a magnetic recording medium of the present invention, a sputtering method may be employed as a method for forming an alignment adjusting film, and a method using a sputtering gas containing oxygen may be employed for forming the alignment adjusting film. The oxygen content of the sputtering gas is preferably 1 to 80 vol%. In the method for manufacturing a magnetic recording medium of the present invention, a sputtering method may be employed as a method for forming an alignment adjusting film, and a method using a sputtering gas containing nitrogen may be employed for forming the alignment adjusting film. The nitrogen content of the sputtering gas is preferably 1 to 80 vol%. The orientation adjusting film may be mainly composed of NiP (P content is 10 to 40 at%). The alignment adjusting film is made of N
iPX (X is Cr, Mo, Si, Mn, W, Nb, T
one or more of i and Zr, and the content of X is 0 to 25 at.
%) As a main component. The sputtering target of the present invention is a sputtering target used for forming an alignment adjustment film when performing the above-described method for manufacturing a magnetic recording medium, and is a NiPX (X
Is characterized by being mainly composed of one or more of Cr, Mo, Si, Mn, W, Nb, Ti, and Zr (X content is 0 to 25 at%). In the magnetic recording medium of the present invention, an orientation adjusting film is formed on a non-metallic substrate having a textured surface, a non-magnetic base film and a magnetic film are formed thereon, and a coercive force Hcc and a diameter in a circumferential direction are formed. The ratio Hcc / Hcr to the coercive force Hcr in the direction is 1.1 or more. In the magnetic recording medium of the present invention, the surface of the orientation control film may be oxidized. Further, a structure in which the surface of the orientation control film is subjected to nitriding treatment can be employed. It is preferable that the orientation adjusting film has NiP (P content: 10 to 40 at%) as a main component. The orientation adjusting film is made of NiPX (X is Cr, Mo,
One or more of Si, Mn, W, Nb, Ti, and Zr, X
(The content is preferably 0 to 25 at%). The thickness of the orientation control film is preferably 2 to 100 nm. The alignment adjustment film has a surface average roughness Ra
Is preferably less than 0.5 nm. The non-metallic substrate is preferably a glass substrate. In the magnetic recording medium of the present invention, a non-magnetic adhesion film is formed between the non-metallic substrate and the orientation adjustment film so that the orientation adjustment film is hardly peeled off from the substrate side. Mo, Nb,
A configuration including one or more of V, Re, Zr, W, and Ti can also be employed. A magnetic recording / reproducing apparatus according to the present invention includes the magnetic recording medium, and a magnetic head for recording / reproducing information on / from the magnetic recording medium.

[0006]

FIG. 1 shows a first embodiment of a magnetic recording medium according to the present invention. The magnetic recording medium shown here is formed on a non-metallic substrate 1 whose surface is textured. An orientation adjusting film 2 is formed, on which a non-magnetic base film 3, a magnetic film 4, and a protective film 5 are sequentially formed.
Hereinafter, the non-metallic substrate 1 and the alignment adjustment film 2 are referred to as a medium substrate 6.

The non-metallic substrate 1 is made of a non-metallic material such as glass, ceramics, silicon, silicon carbide, and carbon. In particular, durability,
It is preferable to use a glass substrate from the viewpoint of cost and the like. Examples of glass used for the glass substrate include amorphous glass and crystallized glass. As the amorphous glass, general-purpose soda lime glass, aluminosilicate glass, and aluminosilicate glass can be used. As the crystallized glass, a lithium-based crystallized glass can be used. In particular, it is preferable to use an amorphous glass having uniform physical properties such as hardness, since the surface can be uniformly textured. As the ceramic substrate, a general-purpose sintered body mainly containing aluminum oxide, aluminum nitride, silicon nitride, or the like, or a fiber reinforced material thereof can be used.

The surface of the non-metallic substrate 1 is textured by wrapping tape using fixed abrasive grains or mechanical texturing using free abrasive grains. It is preferable that the texture line formed on the surface of the non-metallic substrate 1 by the texture processing is along the substrate circumferential direction. The surface average roughness Ra of the non-metallic substrate 1 is 0.1 to 1 nm
(1-10 °), preferably 0.3-0.8 nm (3-
8Å) is desirable.

When the surface average roughness Ra is less than the above range, the nonmetallic substrate 1 becomes excessively smooth, and the effect of increasing the magnetic anisotropy of the magnetic film 4 is reduced. If the surface average roughness Ra exceeds the above range, the smoothness of the medium surface is reduced, the glide height characteristic is reduced, and it is difficult to reduce the flying height of the magnetic head during recording and reproduction. Since the non-metallic substrate 1 has a higher hardness and a lower texture processability than the metal substrate, when the texture process is performed, it is difficult to form an abnormal protrusion such as a burr, and the maximum protrusion height Rp is relatively low.

The orientation adjusting film 2 adjusts the crystal orientation of the non-magnetic base film 3 formed immediately above, further adjusts the crystal orientation of the magnetic film 4 formed thereon, and adjusts the magnetic orientation of the magnetic film 4. This is for improving the anisotropy. Also, the alignment adjusting film 2
Is not only for adjusting the crystal orientation, but also for
Also, it functions as a crystal grain refinement film that refines crystal grains in the magnetic film 4.

As a material of the alignment adjusting film 2, it is preferable to use a material containing NiP as a main component. P content is 1
It is preferably 0 to 40 at% (preferably 15 to 35 at%). If the P content is less than the above range, the material is easily magnetized, and if it exceeds the above range, the crystal orientation of the non-magnetic underlayer 3 and the magnetic film 4 tends to deteriorate. In this specification, the main component is defined as 50
Includes more than at%.

Further, the material of the alignment adjusting film 2 is N
iPX (X is Cr, Mo, Si, Mn, W, Nb, T
It is preferable to use one containing at least one of i and Zr). X content is 0 to 25 at% (preferably 5 to 25 at%, more preferably 10 at%)
２５25 at%). X content of 25
If it exceeds at%, the crystal orientation of the non-magnetic base film 3 and the magnetic film 4 deteriorates, and the magnetic anisotropy decreases.

The thickness of the orientation adjusting film 2 is 2 to 100 nm (2
0 to 1000 °) (preferably 2 to 50 nm). If the thickness is less than the above range, the magnetic anisotropy of the magnetic film 4 decreases, and if it exceeds the above range, the alignment adjustment film 2 is easily peeled and the material cost increases, which is not preferable.

The surface of the orientation adjusting film 2 may or may not be textured. When the surface of the orientation adjusting film 2 is textured, it is preferable that the texture line is along the circumferential direction of the substrate. The surface average roughness Ra of the alignment adjusting film 2 is preferably 1 nm or less from the viewpoint of glide height characteristics. Surface average roughness Ra of alignment control film 2
Is less than 0.5 nm (less than 5 °) (more preferably, 0.
(Less than 3 nm). Since a metal material such as NiPX having relatively low hardness and high workability is used for the alignment adjustment film 2, large protrusions such as burrs and burrs are easily formed on the film surface during texture processing. Therefore, the maximum projection height Rp tends to increase. The surface average roughness Ra of the alignment adjusting film 2 is 0.5 nm.
With less than 5 °, the amount of grinding during texture processing is reduced, and the maximum projection height Rp on the surface is reduced.
Can be prevented from increasing, the maximum protrusion height Rp on the medium surface can be kept small, and deterioration of the glide height characteristic can be prevented.

The nonmagnetic underlayer 3 is made of a conventionally known underlayer material such as Cr, Ti, Ni, Si, Ta, W, Mo,
It can be made of an alloy in which one or more of V and Nb or other elements are added to these in a range that does not impair the crystallinity. Among them, Cr or Cr alloys (for example, CrTi, CrW, CrMo, CrV
, CrSi-based). The nonmagnetic underlayer 3 may have a single-layer structure or a multilayer structure in which a plurality of films having the same or different compositions are stacked. The thickness of the nonmagnetic underlayer 3 is 1 to 100 nm (10 to 10 nm).
1000 °), preferably 2 to 50 nm (20 to 500
Å) is desirable. The crystal orientation of the non-magnetic underlayer 3 is preferably (002).

The magnetic film 4 is preferably made of a material containing Co as a main component. As this material, for example, Cr,
Pt, Ta, B, Ti, Ag, Cu, Al, Au, W,
A Co alloy in which at least one of Nb, Zr, V, Ni, Fe and Mo is added to Co can be used. Preferred specific examples of the above materials include CoCrTa, CoC
An alloy mainly containing an rPt-based, CoCrPtB-based, or CoCrPtTa-based alloy can be given. It is particularly preferable to use a CoCrPtTa-based alloy. The thickness of the magnetic film 4 is 5 to 30 nm (50 to 300 nm).
Å). The crystal orientation of the magnetic film 4 is (11
0) is preferable.

The magnetic film 4 may have a single-layer structure having a uniform configuration, or may have a multilayer structure in which a plurality of layers are stacked. For the layers constituting the multilayer structure film, materials having the same composition or materials having different compositions may be used.

As the material of the protective film 5, a conventionally known material may be used. For example, a single component such as carbon, silicon oxide, silicon nitride, zirconium oxide, or a material containing these as a main component may be used. it can. Protective film 5
Is preferably 2 to 10 nm (20 to 100 °). Further, a lubricating film made of a lubricant such as a fluorinated liquid lubricant such as perfluoropolyether can be provided on the protective film 5 if necessary.

The magnetic recording medium of this embodiment has a ratio Hcc / Hc of the coercive force Hcc in the circumferential direction to the coercive force Hcr in the radial direction.
r is set to 1.1 or more (preferably 1.2 or more). If the ratio Hcc / Hcr is less than the above range, the magnetic anisotropy of the magnetic recording medium will be insufficient, and the magnetic properties such as thermal fluctuation resistance will be insufficient.

Hereinafter, a first embodiment of a method for manufacturing a magnetic recording medium according to the present invention will be described with reference to an example of manufacturing the magnetic recording medium. First, texturing is performed on the surface of the non-metallic substrate 1. As the texturing method, lapping tape using fixed abrasive grains or mechanical texturing using free abrasive grains is preferable. In texture processing, it is preferable to form texture lines in the circumferential direction. Further, in order to remove fine burrs and burrs formed on the film surface by mechanical texturing and obtain higher surface smoothness, chemical etching can be performed after mechanical texturing.

Next, the orientation adjusting film 2 is formed on the non-metallic substrate 1 to obtain the medium substrate 6. The orientation adjusting film 2 is preferably formed by a sputtering method using a sputtering device which is a film forming device. FIG. 2 shows an example of a sputtering apparatus. A sputtering apparatus 21 shown here includes a chamber 22 and
A sputtering target 23 provided on the inner surface of both side walls of the chamber 22, a power supply 24 for supplying power to the target 23, and a bias power supply 2 for applying a bias to the substrate 1
5, a sputtering gas supply means 26 for supplying a sputtering gas into the chamber 22, and an oxygen-containing gas supply means 27 for supplying an oxygen-containing gas into the chamber 22.

As the sputtering target 23,
What consists of the constituent material of the said orientation adjustment film 2 is used. The sputtering target 23 is made of NiPX (X is one or more of Cr, Mo, Si, Mn, W, Nb, Ti, and Zr, and the X content is 0 to 25 at%, preferably 5 to 25 at%.
at% to 25 at%, more preferably 10 at% to 2
(5 at%) as a main component.
When the content of X exceeds the above range, the crystal orientation of the non-magnetic underlayer 3 and the magnetic film 4 deteriorates, and the magnetic anisotropy of the magnetic film 4 decreases. As the sputtering target 23, a sputtering target containing NiP as a main component can also be used.
The P content is 10 to 40 at% (preferably 15 to 35 at%).
at%). If the P content is less than the above range, the material is easily magnetized, and if it exceeds the above range, the crystal orientation of the non-magnetic underlayer 3 and the magnetic film 4 tends to deteriorate.

As the target 23, a sintered alloy target or an alloy target manufactured by a melting method can be used, and it is particularly preferable to use a sintered alloy target. As the sintered alloy target, an alloy powder having the above composition, or a mixture of a plurality of alloy powders or elemental metal powders mixed so as to have the above composition is used.
It can be sintered by a conventionally known sintering method such as IP (hot isostatic press) and hot press. As the alloy powder and the metal powder, those manufactured by a conventionally known method such as a gas atomization method can be used.

In forming the alignment adjusting film 2, the non-metallic substrate 1 is carried into the chamber 22, a sputtering gas such as an argon gas is introduced into the chamber 22 by using a sputtering gas supply means 26, and then the target 23 And the target constituent material is deposited on the non-metal substrate 1 by a sputtering method. The orientation adjusting film 2 is not limited to the sputtering method, and may be formed by a plating method such as an electroless plating method, vacuum deposition, ion plating, or the like.

In the method of manufacturing a magnetic recording medium according to the present embodiment, subsequently, the surface of the alignment adjusting film 2 is subjected to an oxidation treatment. In order to perform the oxidation treatment, a method of bringing the surface of the alignment adjustment film 2 into contact with an oxygen-containing gas can be employed. Air, pure oxygen, and water vapor can be used as the oxygen-containing gas. An oxygen-enriched gas having an increased oxygen content in the air can also be used.

As a specific example of the method of bringing the surface of the alignment adjustment film 2 into contact with an oxygen-containing gas, as described above, after the alignment adjustment film 2 is formed on the substrate 1 in the chamber 22 of the sputtering apparatus 21, Among them, a method of introducing an oxygen-containing gas using the oxygen-containing gas supply means 27 can be mentioned. At this time, the oxygen concentration in the gas to which the alignment adjusting film 2 is exposed (in this case, the gas in the chamber 22) is 1 to 100 vol% (preferably 1 to 70 vol).
%, More preferably 1 to 50 vol%). The use of the oxygen-containing gas allows the oxidation treatment to be performed by an easy operation.

The temperature condition when the surface of the alignment adjusting film 2 is brought into contact with an oxygen-containing gas is adversely affected by the crystallization of the alignment adjusting film 2 which affects the orientation of the non-magnetic underlayer 3 and the magnetic film 4. In order to prevent this, the temperature is preferably lower than the temperature at which the constituent material of the alignment adjustment film 2 is crystallized, for example, 280 ° C. or lower. Further, this temperature can be set to normal temperature or higher. The processing time (exposure time to the oxygen-containing gas) in performing this processing can be appropriately set according to the oxygen content of the oxygen-containing gas. By this processing, at least the vicinity of the surface of the alignment adjustment film 2 is oxidized.

Next, a non-magnetic base film 3 is formed on the orientation adjusting film 2.
To form The non-magnetic underlayer 3 can be formed by a sputtering method using a sputtering device. Next, a magnetic film 4 is formed on the non-magnetic base film 3. The formation of the magnetic film 4 can be performed by a sputtering method using a sputtering apparatus. Next, a protective film 5 is formed on the magnetic film 4. The protective film 5 can be formed by a plasma CVD method, a sputtering method, or the like.

In the method of manufacturing a magnetic recording medium according to the present embodiment, the orientation adjusting film 2 is formed on the non-metallic substrate 1 whose surface is textured, and the surface of the orientation adjusting film 2 is oxidized. Despite the use of the non-metallic substrate 1 which is difficult to impart magnetic anisotropy to the film, the crystal orientation of the non-magnetic base film 3 and the magnetic film 4 formed thereon is improved, 4 can increase the magnetic anisotropy. Therefore, the magnetic characteristics (thermal fluctuation resistance, error rate, S / N, etc.) of the magnetic recording medium can be improved.

The thermal fluctuation resistance is generally good in a medium having a large magnetocrystalline anisotropy constant (Ku). In the magnetic recording medium of the present embodiment, it is considered that the crystal magnetic anisotropy constant (Ku) is improved by increasing the magnetic anisotropy in the circumferential direction, so that the thermal fluctuation resistance is improved.
Note that thermal fluctuation refers to a phenomenon in which a recording bit becomes unstable and the recorded data loses heat, and in a magnetic recording device, it appears as a decay with time of the reproduction output of the recorded data. Thermal fluctuation resistance means that thermal fluctuation is difficult to occur.

Further, the half width of the reproduction output peak is reduced,
The resolution of the reproduction output can be improved. Therefore,
A magnetic recording medium having an excellent error rate can be obtained.

Further, by increasing the magnetic anisotropy,
The coercive force can be improved, and the reproduction output (S) can be improved. Therefore, the S / N can be improved. Further, since the crystal grains in the non-magnetic underlayer 3 are refined and the magnetic grains in the magnetic film 4 grown under the influence of the underlayer 3 can be miniaturized and made uniform, noise (N) Can be reduced. For this reason, the reproduction output per unit film thickness can be improved, and excessive thinning of the magnetic grains can be suppressed and thinned by the thinning of the magnetic film 4, thereby further reducing noise. Therefore, it is possible to further improve the S / N.

In the manufacturing method according to the present embodiment, the orientation adjusting film 2 is formed on the non-metallic substrate 1 on which the texture processing has been performed in a film forming apparatus such as a sputtering apparatus, and then the obtained medium substrate 6 is placed on the non-metallic substrate 1. The non-magnetic base film 3 and the magnetic film 4 can be formed on the alignment adjustment film 2 by using this film forming apparatus without being carried out from the film forming apparatus. Therefore, the manufacturing process can be simplified and the manufacturing cost can be reduced. On the other hand, in the conventional manufacturing method, a film forming step (N
After forming a hard film made of iP or the like), the substrate is once carried out from the film forming apparatus and subjected to a texturing process (texturing on the surface of the hard film), and then a film forming process (formation of a non-magnetic base film and a magnetic film) ), The manufacturing process becomes complicated.

Further, NiPX (X is C
one of r, Mo, Si, Mn, W, Nb, Ti, and Zr
In the case where a material whose main component is X and the content of X is 0 to 25 at%) is used, when forming the alignment control film 2, a sputtering target mainly containing NiPX is used. The film 2 can be easily formed. When a material mainly composed of NiP (P content is preferably 10 to 40 at%) is used for the alignment adjustment film 2, a sputtering target mainly composed of NiP is used for forming the alignment adjustment film 2. By using this, the alignment adjusting film 2 can be easily formed.

In the above magnetic recording medium, an orientation adjusting film 2 is formed on a non-metallic substrate 1 having a textured surface, and a non-magnetic under film 3 and a magnetic film 4 are formed thereon.
Are formed, and the coercive force Hcc in the circumferential direction and the coercive force H in the radial direction are formed.
Since the ratio Hcc / Hcr to cr is 1.1 or more,
It has high magnetic anisotropy and excellent magnetic properties (thermal fluctuation resistance, error rate, S / N, etc.). Further, the manufacturing process can be simplified and the manufacturing cost can be reduced.

In the above magnetic recording medium, the alignment adjusting film 2
If is not textured,
Since texture processing is not required during manufacturing, manufacturing is facilitated and manufacturing cost can be reduced. Further, it is possible to prevent the glide height characteristic from being lowered due to the roughening of the surface shape of the orientation adjusting film 2 due to the texture processing and the increase in the maximum protrusion height Rp on the medium surface. In the case where the orientation adjusting film 2 is textured, the crystal orientation of the non-magnetic underlayer 3 and the magnetic film 4 can be further improved, and the magnetic anisotropy of the magnetic film 4 can be further increased. .

FIG. 3 shows an example of a magnetic recording / reproducing apparatus using the above magnetic recording medium. The magnetic recording / reproducing apparatus shown here includes a magnetic recording medium 7 having a configuration shown in FIG. 1, a medium driving unit 8 for driving the magnetic recording medium 7 to rotate, a magnetic head 9 for recording / reproducing information on / from the magnetic recording medium 7, A head drive unit 10 and a recording / reproducing signal processing system 11 are provided.
The recording / reproducing signal processing system 11 can process a recording signal from the outside and send it to the magnetic head 9, or process a reproduction signal from the magnetic head 9 and send it to the outside.

In this magnetic recording / reproducing apparatus, since the magnetic anisotropy of the magnetic recording medium can be increased,
N. Since the error rate can be improved, a higher recording density can be achieved. In addition, it is possible to prevent troubles such as loss of recorded data due to the thermal fluctuation phenomenon.

Next, a second embodiment of the method for manufacturing a magnetic recording medium according to the present invention will be described. The manufacturing method of the present embodiment includes:
The method is different from the method of the first embodiment in that the surface of the alignment adjustment film 2 is nitrided instead of oxidizing the surface of the alignment adjustment film 2. In order to perform the nitriding treatment, a method of bringing the surface of the alignment adjustment film 2 into contact with a nitrogen-containing gas can be employed. For example, a method of introducing a nitrogen-containing gas into a chamber containing the medium substrate 6 can be adopted. As the nitrogen-containing gas,
Air or pure nitrogen can be used. It is also possible to use a nitrogen-enriched gas having an increased nitrogen content in the air. At this time, the nitrogen concentration in the gas to which the alignment adjusting film 2 is exposed is 1 to 100 vol% (preferably 1 to 70 vol%).
%, More preferably 1 to 50 vol%). By using a nitrogen-containing gas, the nitriding treatment can be performed by an easy operation.

The temperature condition for performing the treatment of bringing the surface of the alignment adjustment film 2 into contact with the nitrogen-containing gas is such that the crystallization of the alignment adjustment film 2 adversely affects the orientation of the nonmagnetic underlayer 3 and the magnetic film 4. In order to prevent this, the temperature is preferably lower than the temperature at which the constituent material of the alignment adjustment film 2 is crystallized, for example, 280 ° C. or lower. Further, this temperature can be set to normal temperature or higher. The processing time (exposure time to the nitrogen-containing gas) when performing this processing can be appropriately set according to the nitrogen content of the nitrogen-containing gas. By this treatment, at least the vicinity of the surface of the alignment adjustment film 2 is nitrided.

In the method of manufacturing a magnetic recording medium according to the present embodiment, the orientation adjusting film 2 is formed on the non-metallic substrate 1 whose surface has been textured, and the surface of the orientation adjusting film 2 is nitrided. As in the manufacturing method of the first embodiment employing the processing, the crystal orientation of the nonmagnetic underlayer 3 and the magnetic film 4 can be improved, and the magnetic anisotropy of the magnetic film 4 can be increased. Therefore, magnetic characteristics such as thermal fluctuation resistance of the magnetic recording medium can be improved.

Also in the manufacturing method of this embodiment, after forming the alignment adjusting film 2 in the film forming apparatus, the non-magnetic undercoat film 3 and the magnetic film 4 are formed on the alignment adjusting film 2 by using the film forming apparatus. Can be formed, so that the manufacturing process can be simplified and the manufacturing cost can be reduced.

In the manufacturing methods of the first and second embodiments, the effect of improving the magnetic anisotropy of the magnetic film 4 by oxidizing or nitriding the surface of the orientation adjusting film 2 is that The film 2 has some characteristics influenced by the textured surface of the substrate 1, and this characteristic, which was hardly exhibited conventionally, is developed by oxidation or nitridation, and this is the crystal orientation of the base film 3 and the magnetic film 4. It is thought that this has been improved, but details have not been elucidated.

In the manufacturing method of the above embodiment,
Although the method of oxidizing or nitriding the surface of the alignment adjustment film 2 in the chamber of the film forming apparatus has been described as an example, the present invention is not limited to this.

Next, a third embodiment of the method for manufacturing a magnetic recording medium according to the present invention will be described with reference to FIGS. The manufacturing method according to the present embodiment uses the alignment adjusting film 2 on the substrate 1.
The method is characterized in that a sputtering method is employed as a method of forming the film, and a gas containing oxygen is used as a sputtering gas introduced into the chamber of the sputtering apparatus when forming the alignment adjustment film 2. Specifically, for example, using the sputtering apparatus 21 shown in FIG. 2, the non-metallic substrate 1 is carried into the chamber 22, and the oxygen-containing sputtering gas is introduced into the chamber 22 using the sputtering gas supply unit 26. A method of supplying power to the target 23 can be adopted. As the oxygen-containing sputtering gas, a gas obtained by adding an oxygen-containing gas (air, pure oxygen, water vapor, oxygen-enriched gas, etc.) to an argon gas or the like conventionally used as a sputtering gas to contain oxygen is used. Can be. If the oxygen content in the sputtering gas is too high, the film-forming efficiency decreases, and if it is too low, the effect of increasing the magnetic anisotropy decreases.
0 vol% (preferably 2 to 50 vol%, more preferably 5 to 30 vol%) is suitable. By using a sputtering gas containing oxygen, the orientation adjusting film 2 contains oxygen.

In the method for manufacturing a magnetic recording medium of the present embodiment, the first and second sputtering gases are used because a sputtering gas containing oxygen is used.
As in the manufacturing method of the embodiment (the manufacturing method of oxidizing or nitriding the alignment adjusting film 2), the crystal orientation of the non-magnetic underlayer 3 and the magnetic film 4 is improved, and the magnetic anisotropy of the magnetic film 4 is increased. be able to. Therefore, magnetic characteristics such as thermal fluctuation resistance of the magnetic recording medium can be improved.

The effect of improving the magnetic anisotropy of the magnetic film 4 can be obtained by using a sputtering gas containing oxygen because the orientation adjustment film 2 contains oxygen, which affects the surface of the substrate 1. And as a result,
It is considered that the orientation adjusting film 2 has some characteristics influenced by the surface of the textured substrate 1, and this characteristic improves the crystal orientation of the non-magnetic base film 3 and the magnetic film 4. Details are unclear.

Also in the manufacturing method of this embodiment, after forming the alignment adjusting film 2 in the film forming apparatus, the non-magnetic undercoat film 3 and the magnetic film 4 are successively formed on the alignment adjusting film 2 by using the film forming apparatus. Can be formed, so that the manufacturing process can be simplified and the manufacturing cost can be reduced. Further, in the manufacturing method of the present embodiment, since the surface treatment after the formation of the alignment adjustment film 2 is not required, the manufacturing process can be further simplified, and the manufacturing cost can be further reduced.

Next, a fourth embodiment of the method for manufacturing a magnetic recording medium according to the present invention will be described with reference to FIGS. The manufacturing method according to the present embodiment uses the alignment adjusting film 2 on the substrate 1.
The method is characterized in that a sputtering method is employed as a method for forming the film, and a nitrogen-containing gas is used as a sputtering gas introduced into the chamber of the sputtering apparatus when forming the alignment adjustment film 2. As the nitrogen-containing sputtering gas, a nitrogen-containing gas (such as air, pure nitrogen, or a nitrogen-enriched gas) may be used, such as an argon gas conventionally used as a sputtering gas.
To which nitrogen is added.
If the nitrogen content in the sputtering gas is too high, the film-forming efficiency decreases, and if it is too low, the effect of increasing the magnetic anisotropy decreases.
%, More preferably 5 to 30 vol%). By using a sputtering gas containing nitrogen, the alignment adjustment film 2 contains nitrogen.

In the method of manufacturing a magnetic recording medium of the present embodiment, since the sputtering gas containing nitrogen is used, the first and second sputtering gases are used.
As in the manufacturing method of the embodiment (the manufacturing method of oxidizing or nitriding the alignment adjusting film 2), the crystal orientation of the non-magnetic underlayer 3 and the magnetic film 4 is improved, and the magnetic anisotropy of the magnetic film 4 is increased. be able to. Therefore, magnetic characteristics such as thermal fluctuation resistance of the magnetic recording medium can be improved.

The effect of improving the magnetic anisotropy of the magnetic film 4 can be obtained by using a sputtering gas containing nitrogen because the orientation adjusting film 2 contains nitrogen and the influence of the surface of the substrate 1 is increased. And as a result,
It is considered that the orientation adjusting film 2 has some characteristics influenced by the surface of the textured substrate 1, and this characteristic improves the crystal orientation of the non-magnetic base film 3 and the magnetic film 4. Details are unclear.

Also in the manufacturing method of the present embodiment, after the orientation adjusting film 2 is formed in the film forming apparatus, the non-magnetic base film 3 and the magnetic film 4 are successively formed on the orientation adjusting film 2 by using the film forming apparatus. Can be formed, so that the manufacturing process can be simplified and the manufacturing cost can be reduced. Further, in the manufacturing method of the present embodiment, since the surface treatment after the formation of the alignment adjustment film 2 is not required, the manufacturing process can be further simplified, and the manufacturing cost can be further reduced.

As shown in FIG. 4, in the magnetic recording medium of the present invention, the non-magnetic adhesion between the alignment adjusting film 2 and the non-metallic substrate 1 makes the alignment adjusting film 2 difficult to peel off from the substrate 1 side. A membrane 12 can also be provided. The nonmagnetic adhesion film 12 includes
A material having excellent adhesion to the non-metallic substrate 1 and the alignment adjustment film 2 such as Cr, Mo, Nb, V, Re, Zr,
An alloy containing at least one of W and Ti as a main component can be used. Suitable materials for the nonmagnetic adhesion film 12 include CrMo-based, CrTi-based, CrV-based, CrW-based alloys, and Cr. Non-magnetic adhesion film 1
The film thickness of 2 is preferably 200 nm or less, for example, 5 to 200 nm. If it exceeds 200 nm, the effect of increasing the magnetic anisotropy of the magnetic film 4 will be reduced. To form the nonmagnetic adhesion film 12, a sputtering method or the like can be used.

In the example shown here, the provision of the non-magnetic adhesive film 12 not only prevents the alignment adjustment film 2 from peeling off, but also prevents the medium from being locally heated during recording and reproduction. The heat of the portion can be immediately diffused in the direction of the medium surface, the temperature rise can be kept low, and a decrease in magnetic properties can be prevented.

In the magnetic recording medium of the present invention, a non-magnetic undercoat film and a magnetic film are provided for the purpose of improving the crystal orientation of the magnetic film and further enhancing the effect of the present invention (improvement of thermal fluctuation resistance and the like). , A non-magnetic intermediate film can be provided. As a material suitably used for the non-magnetic intermediate film, a CoCr-based alloy (Cr content: 20 to 40 at%) can be exemplified. FIG. 5 shows an example of a magnetic recording medium provided with a nonmagnetic intermediate film. In the magnetic recording medium shown here, a nonmagnetic intermediate film 13 is provided between the nonmagnetic base film 3 and the magnetic film 4. Have been. The thickness of the non-magnetic intermediate film 13 can be 5 to 200 nm.

[0056]

EXAMPLES (Test Examples 1 to 4) Hereinafter, the present invention will be described in detail with reference to specific examples. Glass substrate 1 with amorphous structure
(Diameter 65 mm, thickness 0.635 mm) The surface is mechanically textured in the circumferential direction, and the surface average roughness Ra
Was set to the value shown in Table 1. An AFM manufactured by Digital Instrument was used to measure the surface average roughness Ra. After the non-metallic substrate 1 is sufficiently washed and dried, it is set in a chamber of a DC magnetron sputtering apparatus (3010 manufactured by Anelva), and the inside of the chamber is evacuated until the vacuum reaches 2 × 10 ⁻⁷ Pa. An argon gas was introduced as a sputtering gas into the chamber, and an orientation adjusting film 2 was formed on the substrate 1 by a sputtering method.

Next, air as an oxygen-containing gas was introduced into the chamber of the sputtering apparatus, and the surface of the alignment adjustment film 2 was brought into contact with air for 5 seconds to perform an oxidation treatment. At this time, the temperature condition was set to 200 ° C., and the oxygen concentration in the chamber was set to 20 vol%. Then, the medium substrate 6 is heated to 200 ° C. using a sputtering apparatus, and then a non-magnetic underlayer 3 made of Cr is formed on the orientation adjusting film 2 by a sputtering method.
A magnetic film 4 made of an oCrPtTa-based alloy was formed. A protective film 5 made of carbon was formed on the magnetic film 4 by a sputtering method. On the protective film 5, a lubricating film made of perfluoropolyether was formed by a dipping method.

The magnetostatic properties of the obtained magnetic recording medium were measured using a vibration type magnetic property measuring device (VSM). In addition, the ratio of the coercive force Hc in the circumferential direction to the coercive force Hc in the radial direction (Hc in the circumferential direction / Hc in the radial direction) was measured and used as an index of magnetic anisotropy. This shows the coercive force ratio). Further, the electromagnetic conversion characteristics of these magnetic recording media are represented by G
UZIK read / write analyzer RWA1632,
And it measured using the spin stand S1701MP. The evaluation of the electromagnetic conversion characteristics was performed using a composite thin-film magnetic recording head having a giant magnetoresistive (GMR) element in the reproducing section and measuring the recording conditions at a linear recording density of 350 kFCI. Regarding the thermal fluctuation resistance, the spin stand S1
701MP, recording density 40 at 70 ° C
A decrease in power at kFCI was observed. In the table, PW50
Indicates the half width of the output peak.

(Test Example 5) After forming the orientation adjusting film 2, the procedure of Test Example 1 was repeated except that nitridation was performed by introducing pure nitrogen into the chamber instead of introducing air into the chamber to perform oxidation. A magnetic recording medium was manufactured according to the procedure. The nitrogen concentration in the chamber during the nitriding treatment was set to 20 vol%.

(Test Example 6) In forming the orientation adjusting film 2, a mixed gas of argon and nitrogen (argon content 80 vol%, nitrogen content 20 vol) was used as a sputtering gas.
1%) and using no oxidation treatment, a magnetic recording medium was produced according to Test Example 1.

(Test Example 7) Non-metallic substrate 1 and alignment adjusting film 2
Nonmagnetic adhesion film 1 made of Cr by sputtering between
2 (thickness: 100 mm), except that a magnetic recording medium was manufactured according to Test Example 1.

Test Example 8 A magnetic recording medium was manufactured according to the method of Test Example 1, except that the surface of the non-metallic substrate 1 was not textured.

Test Example 9 A magnetic recording medium was manufactured according to the method of Test Example 1, except that the surface of the alignment adjustment film 2 was not oxidized (the process of bringing the alignment adjustment film 2 into contact with air). Table 1 also shows the test results of the magnetic recording media manufactured by the methods of the respective test examples.

[0064]

[Table 1]

As shown in Table 1, compared to the magnetic recording media of Test Examples 8 and 9 produced by a method in which the texture processing on the substrate 1 or the surface treatment was not performed on the alignment adjusting film 2, the substrate 1
It can be seen that the magnetic recording media of Test Examples 1 to 4 and 7 produced by a method of performing texturing on the surface and oxidizing the surface of the alignment adjustment film 2 exhibited excellent magnetic anisotropy. The magnetic anisotropy of Test Example 5 produced by a method of performing a nitriding treatment instead of the oxidation treatment and the magnetic recording medium of Test Example 6 obtained by a method using a nitrogen-containing sputter gas were also excellent. It can be seen that the property was obtained. Further, it can be seen that the magnetic recording media of Test Examples 1 to 7 exhibited excellent thermal fluctuation resistance. Further, it can be seen that the coercive force is high and the half width PW50 of the output peak is small, so that the resolution of the reproduced output is excellent.

(Test Examples 10 to 14) Crystallized glass substrate 1
(Diameter 65mm, thickness 0.635mm, OHARA TS
-10SX), the surface was mechanically textured in the circumferential direction to have a surface average roughness Ra of 5 ° (0.5 nm). After the non-metallic substrate 1 is sufficiently washed and dried,
C magnetron sputtering device (3010 manufactured by Anelva)
Set in the chamber, and reach 2 × in the chamber
After evacuating to 10 ⁻⁷ Pa, an argon gas was introduced as a sputtering gas into the chamber, and a nonmagnetic adhesion film 12 (thickness 100 ° (10 nm)) made of Cr10Mo was formed on the substrate 1 by a sputtering method. An orientation adjusting film 2 shown in Table 2 was formed thereon.

Next, an oxygen-containing gas shown in Table 2 was introduced into the chamber of the sputtering apparatus, and the surface of the alignment adjustment film 2 was brought into contact with the oxygen-containing gas for 5 seconds to perform an oxidation treatment. At this time, the temperature condition was set to 200 ° C., and the oxygen concentration in the chamber was set to 20 vol%. Next, the medium substrate 6 is heated to 200 ° C. using a sputtering apparatus, and then a non-magnetic underlayer 3 (thickness: 200 ° (20 nm)) made of CrMo is formed on the orientation adjusting film 2 by a sputtering method. A nonmagnetic intermediate film 13 (thickness 30 ° (3 nm)) made of CoCr was formed on the base film 3 by sputtering, and a magnetic film 4 (thickness 200 ° (20 nm)) made of a CoCrPtB-based alloy was formed. A protective film 5 made of carbon is formed on the magnetic film 4 by a sputtering method,
A lubricating film made of perfluoropolyether was formed thereon. Table 2 shows the test results of the obtained magnetic recording media. In the table, the used gas refers to the above oxygen-containing gas. 20
% O ₂ —Ar is an oxygen-containing gas (gas in the chamber)
It means an oxygen / argon mixed gas containing 20 vol% oxygen and the balance being Ar. The gas pressure means the pressure of the oxygen-containing gas in the chamber.

[0068]

[Table 2]

Table 2 shows that when NiP was used for the alignment adjusting film 2, the magnetic anisotropy was enhanced by setting the P content to 40 at% or less. It can also be seen that excellent results were obtained for the coercive force, PW50, and thermal fluctuation resistance.

(Test Examples 15 to 25) Magnetic recording media were produced in the same manner as in Test Example 10, except that the oxygen-containing gas used was as shown in Table 3 and the pressure was as shown in Table 3. . Table 3 shows the test results.

[0071]

[Table 3]

As shown in Table 3, when the surface of the orientation adjusting film 2 was oxidized, the oxygen concentration in the oxygen-containing gas was set to 1 at%.
From the above, it can be seen that excellent magnetic characteristics were obtained. Further, the pressure of the oxygen-containing gas is set to 0.1.
It is understood that sufficient magnetic properties can be obtained by setting the pressure to 2 Pa or more, and more excellent magnetic properties can be obtained by setting the pressure to 2 Pa or more.

(Test Examples 26 to 42) A magnetic recording medium was manufactured in the same manner as in Test Example 11, except that the surface average roughness Ra of the substrate, the orientation adjusting film, the oxygen-containing gas, and the pressure were as shown in Table 4. Was prepared. In Test Examples 41 and 42, as the nonmetallic substrate 1, a tempered glass substrate (manufactured by Nippon Sheet Glass) and an alumina sintered substrate (made of aluminum oxide) were used. Table 4 shows the test results. In the table, Air means air.

[0074]

[Table 4]

Table 4 shows that excellent magnetic properties could be obtained even when air was used as the oxygen-containing gas. A steam / argon mixed gas (5% H ₂ O-
It can be seen that excellent magnetic properties could be obtained even when Ar) was used. It can also be seen that sufficient magnetic properties could be obtained even when a tempered glass substrate or an alumina sintered substrate was used. When air is brought into contact with the surface of the alignment adjustment film 2, it is considered that both oxidation and nitridation have occurred. However, since oxygen has higher reactivity than nitrogen, it is considered that oxidation occurs preferentially. Conceivable.

(Test Examples 43 to 53) Crystallized Glass Substrate 1
A nonmagnetic adhesion film 12 (film thickness: 50 ° (5 nm)) made of Cr was formed on (TS-10SX manufactured by OHARA CORPORATION), and an alignment adjustment film 2 shown in Table 5 was formed thereon. Next, a nitrogen-containing gas shown in Table 5 was introduced into the chamber of the sputtering apparatus, and a nitriding treatment was performed at 200 ° C. for 5 seconds. On the orientation adjusting film 2, a non-magnetic base film 3 (film thickness of 150 °)
(15 nm)). The nonmagnetic underlayer 3 is formed by forming a second layer made of CrW on a first layer made of Cr.
A layered film was obtained. On the non-magnetic base film 3, a non-magnetic intermediate film (thickness: 30 ° (3 nm)) made of CoCr and a magnetic film 4 were formed. The magnetic film 4 is formed by depositing Co on a first layer (layer thickness 180 ° (18 nm)) of CoCrPtBCu.
Second layer made of CrPtTa (layer thickness 20 ° (2 nm))
Was formed into a two-layer structure film (film thickness 200 ° (20 nm)). A protective film 5 made of carbon was formed on the magnetic film 4 by a sputtering method, and a lubricating film made of perfluoropolyether was formed thereon. Table 5 shows the test results of the obtained magnetic recording media.

[0077]

[Table 5]

Table 5 shows that excellent magnetic properties could be obtained even when the surface of the orientation adjusting film 2 was subjected to nitriding treatment.

(Test Examples 54 to 64) Crystallized Glass Substrate 1
A nonmagnetic adhesion film 12 (film thickness: 100 ° (10 nm)) made of CrW was formed on (TS-10SX manufactured by OHARA CORPORATION), and an alignment adjustment film 2 shown in Table 6 was formed thereon. The sputtering gas (film forming gas) used at this time was the one shown in Table 6. On the orientation adjusting film 2, a non-magnetic base film 3
(A two-layer structure in which a second layer made of CrW was formed on the first layer made of Cr. A film thickness of 150 ° (15 nm)) was formed by a sputtering method. CoCr on the non-magnetic underlayer 3
A nonmagnetic intermediate film (thickness 30 ° (3 nm)) made of
The magnetic film 4 made of oCrPtTaZr (film thickness 180 °)
(18 nm)). Table 5 shows the test results of the obtained magnetic recording media.

[0080]

[Table 6]

Table 6 shows that excellent magnetic characteristics could be obtained even when oxygen or nitrogen was contained in the sputtering gas (film-forming gas).

[0082]

As described above, according to the method for manufacturing a magnetic recording medium of the present invention, an orientation adjusting film is formed on a non-metallic substrate having a textured surface, and the orientation adjusting film is formed. Since the surface is oxidized or nitrided, the crystal orientation of the non-magnetic underlayer and the magnetic film formed on the non-magnetic substrate can be improved even when using a non-metallic substrate where it is difficult to impart magnetic anisotropy to the magnetic film. And the magnetic anisotropy of the magnetic film can be increased. Therefore, magnetic characteristics such as thermal fluctuation resistance of the magnetic recording medium can be improved. Further, after forming an orientation adjusting film in a film forming apparatus on a textured non-metallic substrate, a non-magnetic base film and a magnetic film can be successively formed by the film forming apparatus. Therefore, the manufacturing process can be simplified, and the manufacturing cost can be reduced.

In the magnetic recording medium of the present invention, an orientation adjusting film is formed on a non-metallic substrate having a textured surface, and a non-magnetic underlayer and a magnetic film are formed thereon. Coercive force Hcc in the direction and coercive force Hcr in the radial direction
, The ratio Hcc / Hcr is 1.1 or more, so that the magnetic anisotropy is high and the magnetic characteristics such as thermal fluctuation resistance are excellent.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing one embodiment of a magnetic recording medium of the present invention.

FIG. 2 is a configuration diagram showing an example of a sputtering apparatus which is a film forming apparatus used for manufacturing the magnetic recording medium shown in FIG.

FIG. 3 is a partial sectional view showing an embodiment of the magnetic recording / reproducing apparatus of the present invention.

FIG. 4 is a partial sectional view showing another embodiment of the magnetic recording medium of the present invention.

FIG. 5 is a partial sectional view showing still another embodiment of the magnetic recording medium of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Non-metallic substrate, 2 ... Orientation adjustment film, 3 ... Non-magnetic base film, 4 ... Magnetic film, 7 ... Magnetic recording medium, 9 ... Magnetic head

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G11B 5/64 G11B 5/64 5/738 5/738 5/84 5/84 Z (72) Inventor Sakaguchi Ryuji 5-1, Hachiman Kaigan-dori, Ichihara-shi, Chiba Prefecture Inside Showa Denko H-D Co., Ltd. (72) Inventor Hiroshi Sakai 5-5-1, Yawata-kaigan Dori, Ichihara-shi, Chiba Prefecture Inside Showa Denko H-D Corporation

Claims (25)

[Claims] 1. An orientation adjusting film for adjusting the orientation of a film immediately above is formed on a non-metallic substrate having a textured surface, and the surface of the orientation adjusting film is oxidized. A method for manufacturing a magnetic recording medium, comprising forming a ground film and a magnetic film. 2. The method for manufacturing a magnetic recording medium according to claim 1, wherein the oxidation treatment is performed by bringing the surface of the orientation adjusting film into contact with an oxygen-containing gas. 3. The method according to claim 2, wherein the oxygen-containing gas is at least one selected from the group consisting of air, pure oxygen, water vapor, and an oxygen-enriched gas. 4. An oxygen-containing gas having an oxygen content of 1 to 1
4% by volume.
The manufacturing method of the magnetic recording medium according to the above. 5. An orientation adjusting film for adjusting the orientation of a film immediately above is formed on a non-metallic substrate having a textured surface, and the surface of the orientation adjusting film is subjected to a nitriding treatment. A method for manufacturing a magnetic recording medium, comprising forming a ground film and a magnetic film. 6. The method for manufacturing a magnetic recording medium according to claim 5, wherein the nitriding treatment is performed by bringing the surface of the orientation adjusting film into contact with a nitrogen-containing gas. 7. The method according to claim 6, wherein the nitrogen-containing gas is at least one selected from the group consisting of air, pure nitrogen, and a nitrogen-enriched gas. 8. The nitrogen-containing gas having a nitrogen content of 1 to 1
8% by volume.
The manufacturing method of the magnetic recording medium according to the above. 9. A magnetic recording medium comprising: a non-metallic substrate having a textured surface formed thereon; an orientation adjusting film for adjusting the orientation of a film immediately above the film; and a non-magnetic underlayer and a magnetic film formed thereon. A method for manufacturing a magnetic recording medium, comprising: employing a sputtering method as a method for forming an alignment adjusting film; and using a sputtering gas containing oxygen when forming the alignment adjusting film. 10. The oxygen content of a sputtering gas is 1 to 10.
The method for producing a magnetic recording medium according to claim 9, wherein the content is 80 vol%. 11. A magnetic recording medium comprising: a non-metallic substrate having a textured surface formed thereon; an orientation adjusting film for adjusting the orientation of a film directly above the film; and a non-magnetic underlayer and a magnetic film formed thereon. A method for manufacturing a magnetic recording medium, comprising: employing a sputtering method as a method for forming an alignment adjusting film; and using a sputtering gas containing nitrogen when forming the alignment adjusting film. 12. The sputter gas has a nitrogen content of 1 to 10.
The method for manufacturing a magnetic recording medium according to claim 11, wherein the content is 80 vol%. 13. The magnetic recording according to claim 1, wherein the orientation adjusting film is mainly composed of NiP (P content is 10 to 40 at%). The method of manufacturing the medium. 14. An alignment adjusting film made of NiPX (X is C
one of r, Mo, Si, Mn, W, Nb, Ti, and Zr
13. The method for producing a magnetic recording medium according to claim 1, wherein the main component is at least one species and the content of X is 0 to 25 at%. 15. A sputtering target used for forming an alignment adjustment film in performing the method for manufacturing a magnetic recording medium according to claim 14, wherein the sputtering target is NiPX.
(X is Cr, Mo, Si, Mn, W, Nb, Ti, Zr
Wherein the content of X is 0 to 25 at%) as a main component. 16. An orientation adjusting film is formed on a non-metallic substrate having a textured surface, a non-magnetic underlayer and a magnetic film are formed thereon, and a circumferential coercive force Hcc and a radial coercive force are formed. Ratio H to magnetic force Hcr
A magnetic recording medium wherein cc / Hcr is 1.1 or more. 17. The magnetic recording medium according to claim 16, wherein the surface of the orientation control film is oxidized. 18. The magnetic recording medium according to claim 16, wherein the surface of the orientation control film is subjected to a nitriding treatment. 19. The magnetic recording according to claim 16, wherein the orientation adjusting film is mainly composed of NiP (P content: 10 to 40 at%). Medium. 20. When the orientation adjusting film is NiPX (X is C
one of r, Mo, Si, Mn, W, Nb, Ti, and Zr
The magnetic recording medium according to any one of claims 16 to 18, wherein the main component is at least one species and the content of X is 0 to 25 at%). 21. A film thickness of an orientation control film is 2 to 100 nm.
The magnetic recording medium according to any one of claims 16 to 20, wherein 22. The alignment adjusting film according to claim 16, wherein the surface average roughness Ra is less than 0.5 nm.
2. The magnetic recording medium according to claim 1, wherein: 23. The magnetic recording medium according to claim 16, wherein the non-metallic substrate is a glass substrate. 24. A non-magnetic adhesion film which makes it difficult for the orientation adjustment film to be peeled off from the substrate side is formed between the non-metallic substrate and the orientation adjustment film, and the non-magnetic adhesion film is made of Cr, Mo,
24. Any one of claims 16 to 23, comprising at least one of Nb, V, Re, Zr, W and Ti.
Item 7. The magnetic recording medium according to Item 1. 25. Any one of claims 16 to 24.
A magnetic recording / reproducing apparatus, comprising: the magnetic recording medium according to claim 1; and a magnetic head for recording / reproducing information on / from the magnetic recording medium.