JPH0729143A - Magnetic recording medium and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a magnetic tape showing a high S/N. CONSTITUTION:A first magnetic layer 12 with a Co base is formed. The film is not larger than 0.1mum thick including 6-35atm.% oxygen. An axis of easy magnetization of the layer is inclined to a normal 16. A second magnetic layer 13 with a Co base is formed on the layer 12. An axis of easy magnetization of the layer 13 is inclined in the same direction as in the first magnetic layer 12 to the normal 16. The second layer 13 has not larger than 0.1mum thickness of film which includes 6-35atm.% oxygen. The coercive force Hc1 of the first magnetic layer 12 in the longitudinal direction and the coercive force Hc2 of the second magnetic layer 13 in the longitudinal direction hold a relationship 1<Hc1/Hc2<=1.5. Moreover, an angle alpha, defined by the axis of easy magnetization of the first magnetic layer and the normal is smaller than an angle alpha2 defined by the axis of easy magnetization of the second magnetic layer and the normal.

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 having a high S / N and a method for manufacturing the same.

[0002]

2. Description of the Related Art The density of magnetic recording / reproducing devices is increasing year by year, and a magnetic recording medium having excellent short wavelength recording / reproducing characteristics is desired. At present, a coated magnetic recording medium in which magnetic powder is coated on a substrate is mainly used, and the characteristics have been improved so as to satisfy the above-mentioned demand, but it is almost the limit.

Thin film magnetic recording media have been developed to exceed this limit. The thin film magnetic recording medium is manufactured by a vacuum deposition method, a sputtering method, a plating method, etc.
It has excellent short wavelength recording / reproducing characteristics. As the magnetic layer in the thin film magnetic recording medium, Co, Co-Ni, Co-
Ni-P, Co-O, Co-Ni-O, Co-Cr, C
o-Ni-Cr and the like have been studied. When it is put into practical use as a magnetic tape, the vacuum vapor deposition method is most suitable as a manufacturing method, and a vapor deposition tape having Co—Ni—O as a magnetic layer has already been put into practical use as a tape for a Hi8 system VTR.

An example of the vapor deposition tape manufacturing method will be described below with reference to FIG. FIG. 2 shows an example of the internal structure of a vacuum vapor deposition apparatus for producing a vapor deposition tape. A polymer film 1 as a substrate runs along a cylindrical can 2 in the direction of arrow 6. Evaporated atoms 9 evaporated from the evaporation source 8 adhere to the polymer film 1 to form a magnetic layer. At that time, the incident angle of the vaporized atoms to the substrate continuously changes from the incident angle θ _{i at the} film formation start portion to the incident angle θ _f of the vaporized atoms at the film formation end portion to the substrate. Here, the incident angle of vaporized atoms is the average incident direction of vaporized atoms to the substrate, measured from the film normal. An electron beam evaporation source is suitable as the evaporation source 8, in which Co as the evaporation substance 7 is contained.
Fill the base alloy. The electron beam evaporation source is used as the evaporation source in order to evaporate a refractory metal such as Co at a high evaporation rate. 3A and 3B are shielding plates provided to prevent unnecessary evaporated atoms from adhering to the substrate. Reference numeral 10 is an oxygen introduction port for introducing oxygen into the vacuum chamber during vapor deposition. Hi8 type VTR currently on the market
The vapor deposition tape for use is manufactured by the method described above.
Reference numerals 4 and 5 are a supply roll and a winding roll of the polymer film 1, respectively.

In the Co—O or Co—Ni—O magnetic layer thus manufactured, the easy axis of magnetization is inclined with respect to the film normal. That is, the axis of easy magnetization is not in the film surface or in the film normal direction, but is in a direction oblique to the film normal in the normal surface including the incident direction of vaporized atoms to the substrate. In the commercially available vapor-deposited tape for Hi8 type VTR, the easy axis of magnetization is inclined by about 70 ° from the normal to the film in the normal plane including the longitudinal direction of the tape. Here, the lengthwise direction of the tape means the lengthwise direction of the tape, and in the production as shown in FIG. 2, it means the running direction of the polymer film.

[0006]

[Problems to be Solved by the Invention] In the future, the magnetic recording / reproducing apparatus will become smaller and larger in capacity. In order to realize this, the linear recording density and the track density must be improved. Therefore, in the magnetic tape, high S / N, especially high S / N in the short wavelength region must be achieved.

[0007]

Means for Solving the Problems The present invention has achieved the above-mentioned needs, and the easy axis of magnetization is tilted with respect to the film normal and contains oxygen in a concentration of 6 to 35 atom% on a substrate. A Co-based first magnetic layer having a film thickness of 0.1 μm or less is formed, and the easy axis of magnetization is tilted in the same direction as the first magnetic layer with respect to the film normal, and 6 to 35 atomic% A second Co-based magnetic layer having a film thickness of 0.1 μm or less containing oxygen at a concentration of 0.1 μm is formed, and the coercive force H _{c1 in} the longitudinal direction of the first magnetic layer and the longitudinal direction of the second magnetic layer Coercive force H _c2 is 1 <H _c1 / H _c2 ≦ 1.5
And the angle between the easy axis of magnetization of the first magnetic layer and the film normal is smaller than the angle between the easy axis of magnetization of the second magnetic layer and the film normal. .

[0008]

With the magnetic recording medium having the structure of the present invention, the reproduction output can be improved and the noise can be reduced, and a high S / N can be obtained.

[0009]

EXAMPLES Next, the magnetic recording medium of the present invention will be explained. FIG. 1 shows the basic structure of the magnetic recording medium of the present invention. In the magnetic recording medium of the present invention, the easy axis of magnetization is tilted with respect to the film normal 16 on the substrate 11, and the first Co-based film having a film thickness of 0.1 μm or less containing oxygen at a concentration of 6 to 35 atomic%. No. 1 magnetic layer 12 is formed, the easy axis of magnetization is tilted in the same direction as the first magnetic layer with respect to the film normal 16 and the film thickness 0 containing oxygen at a concentration of 6 to 35 atomic% is 0. The second magnetic layer 13 having a Co base of 1 μm or less is formed, and the coercive force H _{c1 in} the longitudinal direction of the first magnetic layer 12 and the coercive force H _{c2 in} the longitudinal direction of the second magnetic layer 13 are 1 <H _c1 / H _c2 ≦ 1.5,
In addition, the easy magnetization axis direction 14 of the first magnetic layer 12 and the film normal 1
The angle α ₁ formed by 6 is smaller than the angle α ₂ formed by the easy axis direction 15 of the second magnetic layer 13 and the film normal 16.

With such a structure, the excellent S
The fact that / N is obtained will be described in detail later, and an example of the method of manufacturing the magnetic recording medium of the present invention will be described first with reference to FIG.

When forming the first magnetic layer, the polymer film 1 is run in the direction of arrow 6 along the surface of the cylindrical can 2. Shielding plates 3A and 3B are arranged between the evaporation source 8 and the cylindrical can 2. The vaporized atoms 9 adhere to the polymer film 1 through the openings of the shield plate. The evaporation source 8 is filled with a Co alloy such as Co or Co—Ni as the evaporation material 7. During film formation, oxygen is introduced into the vacuum chamber through the oxygen inlet 10. Polymer film 1 of vaporized atoms at the film formation start portion and the film formation end portion during the formation of the first magnetic layer 1
The angles of incidence on are θ _i1 and θ _f1 , respectively.

Next, a method of forming the second magnetic layer will be described. The polymer film 1 on which the first magnetic layer is formed and wound on the winding roll 5 is run in the direction opposite to the arrow 6 along the circumferential surface of the cylindrical can 2 and is rewound on the supply roll 4. At this time, the evaporation source is turned off and evaporation is stopped. Alternatively, the opening between the shield plates 3A and 3B is closed by a shutter (not shown) to prevent vaporized atoms from adhering to the polymer film.

Next, the polymer film 1 is run in the direction of arrow 6 to form a second magnetic layer. The incident angles of the vaporized atoms at the film formation start portion and the film formation end portion at this time are respectively set to θ _i2 and θ _f2 . The evaporation source 8 is filled with a Co alloy as the evaporation material 7. Further, oxygen is introduced into the vacuum chamber from the oxygen inlet 10.

Regarding the relationship between θ _i1 , θ _f1 , θ _i2 , and θ _f2 , at least the condition of θ _i1 <θ _i2 must be satisfied. If this is not done, the medium having the constitution of the present invention cannot be obtained. Furthermore, θ _f1 ≤ θ _f2 , and more preferably θ _f1 <θ _f2
By setting the above, the medium of the present invention exhibits excellent characteristics. Specific values of θ _i1 , θ _f1 , θ _i2 , and θ _f2 are 6
0 ° ≤ θ _i1 ≤ 85 °, 51 ° ≤ θ _f1 ≤ 70 °, θ _i2 ≥ 8
0 ° and 55 ° ≦ θ _f2 ≦ 75 ° are desirable.

The average oxygen concentration in the film of both the first and second magnetic layers must be within the range of 6 to 35 atomic%. When the oxygen concentration is less than 6 atomic%, a high coercive force cannot be obtained, so that the S / N is low, and further, the corrosion resistance and the durability are poor. On the other hand, if it exceeds 35 atomic%, a high reproduction output cannot be obtained because the saturation magnetization is excessively lowered. Also, the first and second
When the film thickness of both magnetic layers exceeds 0.1 μm, noise becomes high and high S / N cannot be obtained.

Conventionally, a medium design guideline for obtaining a high S / N in a two-layer magnetic recording medium is that the coercive force H _{c1 in} the longitudinal direction of the first magnetic layer on the substrate side and the easy axis direction α _{1 of the} magnetization. And the coercive force H _{c2 in} the longitudinal direction of the second magnetic layer on the surface side and the easy axis direction α _{2 of} the second magnetic layer are considered to be H _c1 <H _c2 and α ₁ > α _2. Was there. On the other hand, the present invention is characterized by satisfying the relations of 1 <H _c1 / H _c2 ≦ 1.5 and α ₁ <α ₂ .

As described above, the reason why the magnetic recording medium of the present invention has a structure completely opposite to that of the conventional magnetic recording medium is that the magnetic recording medium of the present invention has an easy axis of magnetization in a direction oblique to the film normal. It is considered that this is because it has a certain strong magnetic anisotropy.
That is, in the case of a magnetic recording medium having a strong magnetic anisotropy in which a direction easy to magnetize in an oblique direction with respect to the film normal, the configuration of the present invention is adopted when recording a signal with a ring-shaped magnetic head. It is presumed that strong magnetization can be left in the medium.

In order to obtain a high S / N, the conditions of H _c1 > H _c2 and α ₁ <α ₂ which are completely opposite to the conventional conditions are indispensable, but the condition of H _c1 ≦ 1.5 H _c2 is also satisfied. There is a need.
This is because when H _c1 > 1.5H _c2 , the difference between the magnetic layer characteristics of the first layer and the second layer becomes too large.
This is because N decreases.

Since the coercive force is closely related to the magnetic anisotropy, it can be controlled by the inclination angle of the underlayer or columnar crystal grains. First
The means for increasing the longitudinal coercive force of the magnetic layer above the second magnetic layer is as follows.
It is conceivable to make the substrate temperature at the time of forming the first magnetic layer higher than the substrate temperature at the time of forming the second magnetic layer, or to adjust the amount of oxygen introduced.

In addition to these, the first magnetic layer is formed on a substrate which has been subjected to ion treatment and / or electron beam treatment,
There is also a method of forming the second magnetic layer on a substrate that has not been subjected to those treatments. The reason why the magnetic recording medium having the constitution of the present invention can be obtained in this manner is that the magnetic layer is subjected to ion treatment or /
And by forming it on the electron beam treated substrate,
This is because it is possible to increase the coercive force.

Further, Co is formed on the polymer film as a substrate.
Using a base oxide layer formed thereon is effective as a means for making the coercive force in the longitudinal direction of the first magnetic layer higher than the coercive force in the longitudinal direction of the second magnetic layer. The Co-based oxide layer may be formed similarly to the first and second magnetic layers.
However, the amount of oxygen introduced from the oxygen inlet at the time of vapor deposition must be such that the attached film becomes an oxide film.

The magnetic anisotropy of the magnetic layer of the present invention is due to crystal magnetic anisotropy and shape magnetic anisotropy. The Co-based oxide layer as the underlayer of the first magnetic layer has a great influence on the crystal magnetic anisotropy, so that the constitution of the present invention is satisfied, that is, α ₁ <α ₂ depending on the manufacturing conditions of this underlayer. The direction of the easy axis of magnetization can be controlled so that

The easy axis of magnetization is also related to the directions of the columnar crystal grains forming the first and second magnetic layers. When the incident angle of vaporized atoms is changed, the direction of the columnar crystal grains is changed, which affects both the crystal magnetic anisotropy and the shape magnetic anisotropy. The tilt angle of the columnar crystal grains forming the first magnetic layer with respect to the film normal is set to be smaller than the tilt angle of the columnar crystal grains forming the second magnetic layer with respect to the film normal. It is possible to incline the easy axis of magnetization of the magnetic layer with respect to the easy axis of the first magnetic layer.

As described above, the condition of α ₁ <α ₂ can also be realized by controlling the inclination angle of the base or columnar crystal grains, or both of them. That is, a magnetic recording medium having excellent characteristics can be obtained by controlling the tilt angle between the Co-based oxide layer and the columnar crystal grains.

Furthermore, by making the filling rate of the second magnetic layer smaller than that of the first magnetic layer, further noise reduction can be expected. In order to achieve the filling factor as described above, the average incident angle of the second magnetic layer is made larger than the average incident angle of the first magnetic layer, or argon other than oxygen or oxygen during the vapor deposition of the second magnetic layer. It is possible to introduce a gas such as nitrogen.

As described above, the Co-based first magnetic layer containing oxygen having the easy axis of magnetization inclined with respect to the film normal is formed, and the easy axis of magnetization with respect to the film normal is formed thereon. A second Co-based second magnetic layer containing oxygen is formed, and the longitudinal coercive force H _c1 of the first magnetic layer and the longitudinal coercive force H _c2 of the second magnetic layer are formed. 1 <H _c1 / H _c2 ≦ 1.5, and the angle formed between the easy axis of magnetization of the first magnetic layer and the film normal is between the easy axis of magnetization of the second magnetic layer and the film normal. A magnetic recording medium smaller than the angle formed can be obtained.

Next, the lengths of the first magnetic layer and the second magnetic layer
Direction of coercive force and easy axis of magnetization, and recording / reproducing characteristics
The relationship will be described. Coercivity in the longitudinal direction of the first magnetic layer
Power H _c1Is 130 kA / m, and the second magnetic layer is kept in the longitudinal direction.
Magnetic force H_c2Is 120 kA / m and the magnetization of the first magnetic layer is
Angle α between easy axis and membrane normal₁70 °, second magnetic layer
Angle α between the easy axis of magnetization and the film normal₂Is 73 °,
That is, in the case of one example of the present invention (1), H_c1Is 120k
A / m, H_c2Is 130 kA / m, and α₁Is 70 °,
α₂When the angle is 73 ° (2), H_c1Is 130 kA / m,
H_c2Is 80 kA / m, and α₁Is 70 °, α₂Is 73 °
In case of (3), H_c1Is 130 kA / m, H_c2Is 120
kA / m, α₁Is 73 °, α₂When is 70 °
(4), H_c1Is 120 kA / m, H_c2Is 130 kA / m
And α₁Is 73 °, α₂When the angle is 70 ° (5), H
_c1Is 130 kA / m, H_c2Is 80 kA / m₁Is 73
°, α₂If the angle is 70 °, then (6)
An example of the reproduction output and noise in the case of the above is shown in (Table 1). More than
The characteristics of magnetic recording media include the incident angle during film formation and the amount of introduced oxygen.
It changed and it produced. When measuring the recording / reproducing characteristics,
A carbon protective film with a film thickness of 10 nm and a film thickness of 3 nm on the surface
A lubricant was formed. The reproduction output is a signal with a wavelength of 0.5 μm.
Values and noise when recording and reproducing are signals with a wavelength of 0.5 μm
At a frequency corresponding to a wavelength of 0.6 μm when recording and reproducing
Is the value of. In addition, the values in (Table 1) are the values of (1) 0d
B is shown as a relative value to this.

[0028]

[Table 1]

The reproduction output of (1) increases with respect to (2) because (1) has the optimum relationship between the direction of the head magnetic field and the coercive force in that direction. Seem. As a result, it is considered that recording can be performed by effectively utilizing the head magnetic field and that recording demagnetization can be reduced. The noises of (1) and (2) are almost the same because the coercive force of the whole magnetic layer is almost the same and the inclination angle of the easy magnetization axis is also the same.

The reproduction output of (3) is 2 dB lower than that of (1) and the noise of (3) is 1 dB higher than that of (1) because the coercive force of the second magnetic layer is higher than that of the first magnetic layer. It seems that it is because it is too low. Thus, if H _c1 > 1.5H _c2 , a high S / N cannot be obtained.

The reproduction output of (4) and (5) is lower than that of (1) because the inclination angle of the easy axis of magnetization of the second magnetic layer of (4) and (5) is small, resulting in spacing loss. It is thought that this is because the output decreases significantly at short wavelengths.

In (6), since the inclination angle of the easy axis of the second magnetic layer is small and the coercive force is too low, the reproduction output is significantly low and the noise is high.

As described above, in the Co-based oblique vapor deposition medium containing oxygen having a two-layer structure, the highest S / N can be obtained by the constitution of the present invention.

Next, specific examples will be described. First, a CoO film as a Co-based oxide layer was formed on the polymer film 1 with the structure shown in FIG. The evaporation source 8 was filled with Co as the evaporation substance 7, and vapor deposition was performed. The diameter of the cylindrical can 2 was 1 m, and its surface temperature was room temperature. As the polymer film 1, a polyethylene terephthalate film having a thickness of 7 μm was used. θ _i is 35 °, θ _f
Was set at 20 °. Also, from the oxygen inlet 10 l / l
A min amount of oxygen was introduced into the vacuum chamber. In this way, an oxide layer having a thickness of 0.02 μm was formed with an average film deposition rate of 0.5 μm / s.

Next, the C wound on the winding roll 5
The polymer film on which the oO film was formed was rewound on the supply roll 4. At this time, the opening of the shielding plate was closed by a shutter (not shown).

Next, a first magnetic layer was formed. As the evaporation material 7, Co filled at the time of forming the CoO film was used as it was. The surface temperature of the cylindrical can was room temperature. θ _i1 was set to 75 ° and θ _f1 was set to 55 °. The amount of oxygen introduced from the oxygen inlet 10 was 1.2 l / min. Thus, the first magnetic layer having a film thickness of 0.05 μm was formed with an average film deposition rate of 0.3 μm / s.

Next, the film was taken up by the take-up roll 5,
The polymer film on which the CoO film and the first magnetic layer were formed was rewound on the supply roll 4. At this time, the opening of the shielding plate was closed by a shutter (not shown).

Finally, the second magnetic layer was formed. As the evaporative substance 7, Co which was already filled was used as it was. The surface temperature of the cylindrical can was room temperature. θ _i2 is 85
And θ _f2 were set to 65 °. The amount of oxygen introduced from the oxygen inlet 10 was 0.8 l / min. In this way, the average film deposition rate is 0.2 μm / s, and the film thickness is 0.05
A second magnetic layer of μm was formed.

The coercive force of the first magnetic layer is 140 kA / m,
α ₁ is 70 °, and the coercive force of the second magnetic layer is 130 kA /
m and α ₂ were 73 °.

The medium thus produced was slit into a tape shape, and the gap length of sendust was 0.18 μm.
The recording and reproducing characteristics were evaluated using a ring-shaped magnetic head of m. At this time, a carbon protective film having a film thickness of 10 nm and a lubricant having a film thickness of 3 nm were formed on the surface of the medium. As a result, a commercially available Hi8 type VTR vapor deposition tape has a recording wavelength of 5 μm, 2 dB, and a recording wavelength of 0.5 μm, 7 dB, 0.4 μ.
A reproduction output of 8 dB higher at m was obtained. Also, the noise was about 1 dB lower over the entire band. As described above, the magnetic tape of the present invention has a significantly higher S / N than the conventional vapor deposition tape.

In the above, θ _i1 is 75 °, θ _f1 is 55 °,
By forming the first and second magnetic layers of Co—O with θ _{i2 set} to 85 ° and θ _f2 set to 65 °, it is possible to obtain a medium having a high S / N ratio exceeding that of a commercially available vapor deposition tape. explained. However, the coercive force H in the longitudinal direction of the first magnetic layer is also obtained under other manufacturing conditions, manufacturing methods or compositions.
_c1 and the coercive force H _{c2 in} the longitudinal direction of the second magnetic layer are 1 <H _c1 /
H _c2 ≦ 1.5 and the angle between the easy axis of magnetization of the first magnetic layer and the film normal is smaller than the angle between the easy axis of magnetization of the second magnetic layer and the film normal. By doing so, a high S / N can be achieved.

In the above, an example of Co--O was described as the composition of the magnetic layer, but the composition is not limited to this, and C
o-Ni-O, Co-Fe-O, Co-Ni-Fe-O
Even if the composition is such as the above, by using the constitution of the present invention, high S
/ N is obtained. Although the polyethylene terephthalate film has been described as the substrate, it goes without saying that the same applies to a polymer film such as a polyethylene naphthalate film, a polyimide film, a polyamide film, and a polyetherimide film.

Although only the example in which the second magnetic layer is directly formed on the first magnetic layer has been described above, a non-magnetic intermediate layer may be formed between both magnetic layers. In this case, unless the thickness of the non-magnetic intermediate layer is 0.02 μm or less, the reproduction output will decrease.

[0044]

According to the present invention, a magnetic recording medium having a high S / N can be provided.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic configuration of a magnetic recording medium of the present invention.

FIG. 2 is a diagram showing an outline of the inside of a vacuum vapor deposition device for explaining a conventional and present invention magnetic recording medium manufacturing method.

[Explanation of symbols]

 1 Polymer Film 2 Cylindrical Can 3A, 3B Shielding Plate 4 Supply Roll 5 Winding Roll 6 Substrate Traveling Direction 7 Evaporation Material 8 Evaporation Source 9 Evaporation Atoms 10 Oxygen Inlet 11 Substrate 12 First Magnetic Layer 13 Second Magnetic Layer 14 Magnetization easy axis direction of first magnetic layer 15 Magnetization easy axis direction of second magnetic layer 16 Film normal

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuya Yoshimoto 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (8)

[Claims] 1. A film thickness of 0.1, which has an axis of easy magnetization on the substrate and is inclined with respect to a film normal, and which contains oxygen at a concentration of 6 to 35 atomic%.
A Co-based first magnetic layer of μm or less is formed, on which the easy axis of magnetization is inclined in the same direction as the first magnetic layer with respect to the film normal, and oxygen having a concentration of 6 to 35 atomic% is formed. Including the film thickness of 0.
A Co-based second magnetic layer of 1 μm or less is formed,
The coercive force H _{c1 in} the longitudinal direction of the first magnetic layer and the coercive force H _{c2 in} the longitudinal direction of the second magnetic layer have a relationship of 1 <H _c1 / H _c2 ≦ 1.5, and the first magnetic layer The magnetic recording medium is characterized in that the angle formed by the easy axis of magnetization and the film normal is smaller than the angle formed by the easy magnetization axis of the second magnetic layer and the film normal. 2. The tilt angle of the columnar crystal grains forming the first magnetic layer with respect to the film normal line is smaller than the tilt angle of the columnar crystal grains forming the second magnetic layer with respect to the film normal line. The magnetic recording medium according to claim 1, wherein: 3. The magnetic recording medium according to claim 2, wherein the filling rate of the first magnetic layer is higher than the filling rate of the second magnetic layer. 4. The substrate is a polymer film having a Co-based oxide layer formed on the polymer film.
Alternatively, the magnetic recording medium according to 2 or 3. 5. A Co-based oxide layer is formed on a running polymer film by a vacuum deposition method, and 6 to 35 is formed thereon.
A Co-based first magnetic layer having a film thickness of 0.1 μm or less containing an oxygen concentration of 0.1% is formed, and further, a Co film having a film thickness of 0.1 μm or less containing an oxygen concentration of 6 to 35 atom% is formed thereon. In the second magnetic layer, the angle of incidence of vaporized atoms on the substrate at the film formation start portion is larger than the angle of incidence of vaporized atoms on the substrate at the film formation start portion at the time of forming the first magnetic layer. A method of manufacturing a magnetic recording medium, which comprises forming the magnetic recording medium. 6. The incident angle of the vaporized atoms on the substrate at the film formation end portion when the first magnetic layer is formed is the incident angle of the vaporized atom at the substrate at the film formation end portion when the second magnetic layer is formed. The magnetic recording medium manufacturing method according to claim 5, wherein the magnetic recording medium is smaller than the above. 7. The incident angle θ _i1 of vaporized atoms to the substrate at the film forming start portion of the first magnetic layer is ₆₀ to 85 °, and the incident angle θ _f1 of vaporized atoms to the substrate at the film forming end portion is 51. ~ 70
The incident angle θ _i2 of vaporized atoms at the film formation start portion of the second magnetic layer is 80 ° or more, and the incident angle θ _f2 of vaporized atoms at the film formation end portion of the substrate is 55 to 75 °. _{6. The} method of manufacturing a magnetic recording medium according to claim 5, wherein: θ _i1 <θ _i2 and θ _f1 ≦ θ _f2 . 8. The first magnetic layer is ion-treated or //
And a second magnetic layer formed on the substrate which has been subjected to an electron beam treatment without being subjected to an ion treatment or an electron beam treatment on the first magnetic layer. A method for manufacturing a magnetic recording medium according to any one of the above.