JP2003168207A - Perpendicular magnetic recording medium and manufacturing method for perpendicular magnetic recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a perpendicular magnetic recording medium free from elution of Co from a granular magnetic layer and having excellent electromagnetic transducing characteristics, durability, and productivity and to provide a manufacturing method therefor. <P>SOLUTION: The magnetic layer of the perpendicular magnetic recording medium is constituted of a first magnetic layer 14 of a CoCr based alloy which has a granular structure and whose non-magnetic grain boundary consists of metal oxides or nitrides and a second magnetic layer 15 of a CoCr based alloy which has a non-granular structure and whose non-magnetic grain boundary does not contain metal oxides nor nitride. Thereby, in the first magnetic layer 14, satisfactory electromagnetic transducing characteristics due to the granular structure thereof is secured, while in the second magnetic layer 15, Co atoms eluted from the non-magnetic grain boundary of the first magnetic layer are blocked and high durability of the medium can be secured. Spike noise caused by a soft magnetic backing layer 24 can be drastically suppressed by additionally providing a multi layered base layer 22 and a magnetic domain controlling layer 23 between a non-magnetic substrate 21 and the soft magnetic backing layer 24. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a perpendicular magnetic recording medium and a method for manufacturing a perpendicular magnetic recording medium, and more particularly, it has excellent electromagnetic conversion characteristics and good durability and is excellent in productivity. And a method for manufacturing the same.

[0002]

2. Description of the Related Art As a technique for realizing high density of magnetic recording, a perpendicular magnetic recording system is attracting attention in place of the conventional longitudinal magnetic recording system.

As a material for a magnetic recording layer for a perpendicular magnetic recording medium, a CoCr type alloy crystalline film is currently being studied, and a hexagonal closest packing (hcp) structure is used for use in perpendicular magnetic recording. The crystal orientation is controlled so that the c-axis of the CoCr-based alloy is perpendicular to the film surface (the c-plane is parallel to the film surface). For further densification of CoCr-based alloys in the future, refinement of CoCr-based crystal grains, reduction of grain size distribution,
Attempts have been made to reduce the magnetic interaction between grains.

On the other hand, as one method of controlling the magnetic layer structure for increasing the density of the longitudinal recording medium, for example, Japanese Patent Laid-Open No. 8-255 is known.
No. 342 and US Pat. No. 5,679,473 propose a magnetic layer generally called a granular magnetic layer having a structure in which magnetic crystal grains are surrounded by a non-magnetic non-metallic substance such as oxide or nitride. There is. In such a granular magnetic film, the non-magnetic non-metal grain boundary phase physically separates the magnetic particles, so that the magnetic interaction between the magnetic particles is reduced and the zigzag magnetic domain wall generated in the transition region of the recording bit is reduced. Since formation is suppressed, it is considered that low noise characteristics can be obtained, and it has been proposed to use a granular magnetic layer as a recording layer of a perpendicular magnetic recording medium. For example, IE
EE Trans., Mag., Vol. 36, 2393 (2000) contains Ru.
Has been described, and a perpendicular recording medium having a CoPtCrO alloy having a granular structure as a magnetic layer has been described. The c-axis orientation is improved as the thickness of the Ru layer, which is the underlayer of the granular magnetic layer, is increased. Accordingly, excellent magnetic characteristics and electromagnetic conversion characteristics have been obtained.

On the other hand, in a magnetic recording apparatus using a floating magnetic head, the distance between the magnetic head and the magnetic recording medium is as small as several tens of nm, so that the frictional wear characteristics between the head and the medium are different from those of the apparatus. Strongly affects durability. Therefore, it is generally practiced to improve the friction and wear characteristics with the head by applying a liquid lubricant having a molecular weight of several thousand to the surface of the medium. Here, when the Co atoms contained in the magnetic layer of the medium are deposited on the medium surface, the Co atoms may accelerate the decomposition of the liquid lubricant on the medium surface and may significantly deteriorate the durability of the medium. Are known. Therefore, in order to prevent such precipitation of Co atoms, management of the film thickness and film quality of the medium protective film, control of the medium surface roughness, and the like are essential for producing the medium.

[0006]

However, according to the study by the present inventors, when a granular magnetic layer is used as the magnetic layer, Co atoms contained in the magnetic layer are easily deposited on the medium surface. found. In particular, in order to obtain excellent magnetic characteristics and electromagnetic conversion characteristics, Ar during sputtering film formation
The amount of Co elution becomes more remarkable when the gas pressure is increased. When Co atoms are deposited on the surface of the medium, the Co atoms decompose liquid lubricant molecules on the surface of the medium, resulting in a problem that the friction and wear durability of the medium is significantly deteriorated.

The present invention has been made in view of the above problems, and an object thereof is to suppress elution of Co from the granular magnetic layer to provide excellent electromagnetic conversion characteristics and good durability. It is an object of the present invention to provide a perpendicular magnetic recording medium and a method for manufacturing the same, which are compatible with each other.

[0008]

In order to achieve such an object, the present invention provides a soft magnetic backing layer, an intermediate layer and a CoCr system on a non-magnetic substrate. A perpendicular magnetic recording medium in which a magnetic layer of an alloy layer, a protective layer, and a liquid lubricant layer are sequentially laminated, the magnetic layer comprising:
It is characterized by comprising a first magnetic layer having a granular structure provided on the intermediate layer side and a second magnetic layer having a non-granular structure provided on the protective layer side.

The invention described in claim 2 is the same as claim 1.
The perpendicular magnetic recording medium as described in (1) above, wherein the intermediate layer has a hexagonal close-packed (hcp) crystal structure of Ti, Re,
Ru, Os metal, Ti, Re, R
It is characterized by being composed of an alloy containing at least one metal of u and Os.

Further, the invention described in claim 3 is the same as claim 1.
Or in the perpendicular magnetic recording medium according to 2, wherein an underlayer on the nonmagnetic substrate side and a magnetic domain control layer on the soft magnetic underlayer side are sequentially laminated between the nonmagnetic substrate and the soft magnetic underlayer. It is characterized by

According to a fourth aspect of the present invention, there is provided a method of manufacturing a perpendicular magnetic recording medium, comprising a step of forming a soft magnetic backing layer on a non-heated non-magnetic substrate, and an intermediate step on the soft magnetic backing layer. A step of forming a layer, a step of forming a first magnetic layer of a CoCr-based alloy layer having a granular structure on the intermediate layer by a sputtering method, and a step of forming a non-granular structure on the first magnetic layer. Forming a second magnetic layer of the CoCr alloy layer by a sputtering method, forming a protective layer on the second magnetic layer, and forming a liquid lubricant layer on the protective layer And a gas pressure at the time of forming the first magnetic layer is 10 mTorr or more, and a gas pressure at the time of forming the second magnetic layer is 15 mTorr or less.

The invention according to claim 5 is the same as claim 4
The method for manufacturing a perpendicular magnetic recording medium according to the item 1, further comprising a step of heat-treating the nonmagnetic substrate in a film forming apparatus after forming the second magnetic layer.

The invention according to claim 6 is the same as claim 5
The method of manufacturing a perpendicular magnetic recording medium according to the aspect 1, further comprising a step of rapidly cooling the nonmagnetic substrate in a film forming apparatus after the heat treatment of the nonmagnetic substrate.

Furthermore, the invention according to claim 7 is the invention according to claim 4.
7. The method of manufacturing a perpendicular magnetic recording medium according to any one of 1 to 6, further comprising: a step of forming an underlayer on the nonmagnetic substrate, and a step of forming a magnetic domain control layer on the underlayer. It is characterized by

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram for explaining a constitutional example of a perpendicular magnetic recording medium of the present invention. In the perpendicular magnetic recording medium, a soft magnetic backing layer 12, an intermediate layer 13 and a first magnetic layer are formed on a non-magnetic substrate 11.
The magnetic layer 14, the second magnetic layer 15, and the protective layer 16 are sequentially laminated, and the liquid lubricant layer 17 is further formed on the protective layer 16.

FIG. 2 is a diagram for explaining another example of the configuration of the perpendicular magnetic recording medium of the present invention. The perpendicular magnetic recording medium comprises a non-magnetic substrate 21 and a multi-layered lower layer. The ground layer 22, the magnetic domain control layer 23, the soft magnetic backing layer 24, the intermediate layer 25, the first magnetic layer 26, the second magnetic layer 27, and the protective layer 28 are sequentially laminated, and further on the protective layer 28. Is formed by forming a liquid lubricant layer 29.

In the perpendicular magnetic recording medium of the present invention, the non-magnetic substrates 11 and 21 are made of NiP-plated Al alloy or tempered glass used for ordinary magnetic recording media.
Alternatively, crystallized glass or the like can be used, and as the magnetic domain control layer 23, PtMn, I made of an alloy system containing Mn,
An antiferromagnetic film such as rMn, or CoCrTa, CoCrPt with magnetization oriented in the radial direction of the non-magnetic substrate 21,
A hard magnetic film such as a CoCrPtB film can be used. The magnetic domain control layer 23 preferably has a film thickness of about 5 to 300 nm.

A magnetic domain control layer 23 is used as the multilayer underlayer 22.
When using an Mn alloy-based antiferromagnetic film as above, it is desirable to use a nonmagnetic single metal such as Cu or Ir having a face-centered cubic (fcc) structure, or a nonmagnetic alloy such as NiFeCr. In this case, in order to control the fine structure of these non-magnetic single metal film or non-magnetic alloy film, Ta, Zr, and
A layer of Nb or the like may be provided. When a hard magnetic film is used as the magnetic domain control layer 23, a Cr alloy such as CrMo or CrW can be used as the multilayer underlayer 22. Also in this case, an underlying layer may be further provided as an underlying layer for controlling the fine structure of these Cr alloy films. The multilayer underlayer 22 does not necessarily have to be a multilayer underlayer composed of a plurality of layers, and may be a single underlayer if desired.

As the soft magnetic backing layers 12 and 24, Ni is used.
An Fe alloy, a sendust (FeSiAl) alloy or the like can be used, but an amorphous Co alloy such as CoNbZ.
By using r, CoTaZr, or the like, good electromagnetic conversion characteristics can be obtained. The soft magnetic backing layer 1
The optimum values of the film thicknesses of 2 and 24 vary depending on the structure and characteristics of the magnetic head used for magnetic recording, but it is preferably 10 nm or more and 300 nm or less in consideration of productivity.

For the intermediate layers 13 and 25, a material for suitably controlling the crystal orientation, the crystal grain size, and the grain boundary segregation of the first magnetic layers 14 and 26 can be appropriately used. From the viewpoint of controlling the crystal orientation of the magnetic layers 14 and 26 of No. 1, Ti having a hexagonal close-packed (hcp) crystal structure,
Re, Ru, Os metal, Ti, R
An alloy containing at least one metal selected from e, Ru, and Os is desirable. The film thickness is not particularly limited, but from the viewpoint of improving the recording / reproducing resolution and productivity, it is the minimum required for controlling the crystal structure of the first magnetic layers 14 and 26. It is desirable to set the film thickness.

The first magnetic layers 14 and 26 are composed of CoCr-based alloy crystal grains having ferromagnetism and non-magnetic grain boundaries surrounding them, and the non-magnetic grain boundaries are composed of metal oxides or nitrides. , A so-called granular magnetic layer. This granular structure is produced by, for example, sputtering targeting a ferromagnetic metal containing an oxide forming a non-magnetic grain boundary or reactive sputtering targeting a ferromagnetic metal in an Ar gas atmosphere containing oxygen. can do. In order to obtain good characteristics as a granular magnetic layer, the gas pressure during film formation should be 10 mTorr.
It must be greater than or equal to r.

Here, a CoCr-based alloy is preferably used as a material for forming a crystal having ferromagnetism, and particularly from the viewpoint of obtaining excellent magnetic characteristics and recording / reproducing characteristics.
At least one of Pt, Ni, and Ta in a CoCr alloy
It is desirable to add two elements. On the other hand, as the material forming the non-magnetic grain boundary, from the viewpoint of forming a stable granular structure, Cr, Co, Si, Al, Ti, Ta,
It is desirable to use an oxide of at least one element of Hf and Zr, and its film thickness is desirably 30 nm or less in order to enhance the recording / reproducing resolution.

The second magnetic layers 15 and 27 are made of a non-granular structure CoCr-based alloy crystalline film containing no metal oxide or nitride in the non-magnetic grain boundaries. This Co
Examples of materials that can be used for forming the Cr-based alloy crystalline film include CoCr, CoCrTa, CoCrPt, and CoCr.
Examples include alloy-based materials such as PtTa and CoCrPtB. In order to manufacture a perpendicular magnetic recording medium having excellent durability, the gas pressure for forming the second magnetic layers 14 and 27 needs to be 15 mTorr or less, and the film thickness is 20 nm or less. Is desirable.

That is, in the perpendicular magnetic recording medium of the present invention, the magnetic layer for performing magnetic recording is composed of two layers, and the first magnetic layer on the non-magnetic substrate side has the non-magnetic grain boundary of metal oxidation. CoCr with granular structure composed of oxide or nitride
A second magnetic layer formed of a system alloy and provided thereon,
It is composed of a non-granular structure CoCr-based alloy containing no metal oxide or nitride in the non-magnetic grain boundary. Among these magnetic layers, the first magnetic layer ensures good electromagnetic conversion characteristics due to its granular structure, while the second magnetic layer elutes from the non-magnetic grain boundaries of the first magnetic layer. C coming
It is constructed so as to block the atoms and ensure the high durability of the medium.

As the protective layers 16 and 28, conventionally used protective films can be used, for example, a protective film mainly containing carbon can be used. The liquid lubricant layers 17 and 29 can also be made of conventionally used materials, for example, perfluoropolyether-based lubricants can be used. In addition, the protective layers 16 and 28
As the conditions such as the film thickness of the magnetic recording medium and the conditions such as the film thickness of the liquid lubricant layers 17 and 29, various conditions used in a normal magnetic recording medium can be used as they are.

An embodiment of the method of manufacturing the perpendicular magnetic recording medium of the present invention will be described below. Note that these examples are merely representative examples for suitably explaining the method of manufacturing the perpendicular magnetic recording medium of the present invention, and are not limited to these.

(Example 1) As a non-magnetic substrate, a chemically strengthened glass substrate having a smooth surface (for example, N-5 glass substrate manufactured by HOYA) was used, and after cleaning, the substrate was introduced into a sputtering apparatus to make CoZrNb amorphous. 200nm soft magnetic backing layer,
After stacking a Ru intermediate layer of 30 nm, CoCrPt-S
A first magnetic layer having a thickness of 20 nm was formed by an RF sputtering method using an iO ₂ target, and a _second magnetic layer having a thickness of 10 nm was formed using a CoCrPtB target. Here, the first magnetic layer and the second magnetic layer are formed under the condition that the gas pressure is variously changed. Finally, after forming a protective layer of 5 nm of carbon, the protective layer of 5 nm was taken out from the vacuum device, and then the liquid lubricant layer 2 of perfluoropolyether was formed.
nm was formed by the dip method to obtain a perpendicular magnetic recording medium. The substrate heating prior to film formation and the heating / quenching treatment after the magnetic layer film formation were not performed.

The perpendicular magnetic recording medium thus prepared was left in a high temperature and high humidity environment of 85 ° C. and 80% RH for 96 hours, and then shaken in 50 ml of pure water for 3 minutes to extract the eluted Co. And its concentration was measured by ICP emission spectroscopy. The magnetization curves of the medium after the first and second magnetic layers are formed are measured by a vibrating sample magnetometer to evaluate the magnetic characteristics, and the electromagnetic conversion characteristics of the medium in which all layers are formed are G
It was evaluated by a spin stand tester equipped with an MR head.

Table 1 shows the results of collecting the Co elution amount of the perpendicular magnetic recording media produced by changing various gas pressures when forming the first and second magnetic layers.

[0031]

[Table 1]

As is clear from this table, the elution amount of Co can be suppressed by reducing the gas pressure during film formation in both the first magnetic layer and the second magnetic layer. Particularly, when the gas pressure of the second magnetic layer is set to 15 mTorr or less, the elution amount of Co can be suppressed to 10 μg / m ² or less regardless of the gas pressure of the first magnetic layer.

Table 2 summarizes the SNR (ratio of signal to noise of electromagnetic conversion characteristics) at 350 kFCl of the perpendicular magnetic recording medium produced by changing the gas pressure during film formation of the first and second magnetic layers. It is the result.

[0034]

[Table 2]

As can be seen from this table, when the gas pressure during the film formation of the first magnetic layer is set to 15 mTorr or higher, the good pressure of 15 dB or higher is obtained regardless of the gas pressure during the film formation of the second magnetic layer. Excellent electromagnetic conversion characteristics are obtained. Further, in the region where the gas pressure during film formation of the second magnetic layer is 15 mTorr or less, a value of 15 dB or more is obtained even in the medium whose gas pressure during film formation of the first magnetic layer is 10 mTorr or more.

Thus, the Co elution amount was 10 μg / m ²
SN at the recording density of 350 kFCl
In order to set the R value to 15 dB or more, it is necessary to set the gas pressure during film formation of the first magnetic layer to 10 mTorr or higher and the gas pressure during film formation of the second magnetic layer to 15 mTorr or lower. I understand.

(Example 2) A substrate was heated prior to film formation (pre-heating), heating after film formation of the second magnetic layer (post-heating), and quenching treatment in the same apparatus. A magnetic recording medium was manufactured in the same manner as in Example 1 except for the above. However, the gas pressure during film formation of the first magnetic layer is 50 mTorr.
r, the gas pressure during film formation of the second magnetic layer was kept constant at 5 mTorr.

Table 3 shows that the pre-heating temperature is 200 ° C., the post-heating temperature is 200 ° C., and the cooling treatment step which is continuously performed after the post-heating treatment is adjusted so that the substrate temperature after 10 seconds becomes 100 ° C. It is the result of collecting the values of coercive force (Hc) and SNR value depending on the presence or absence of the process.

[0039]

[Table 3]

As can be seen from this table, the magnetic properties and the SNR are drastically reduced by performing the pre-heating treatment, and it is necessary to heat the granular magnetic layer as the first magnetic layer in advance. It is necessary to carry out the film forming process without doing so. When the post heat treatment is performed, the magnetic characteristics and SN are
The value of R has increased significantly. This is because the post-heat treatment improved the characteristics of the CoCr-based alloy crystalline film as the second magnetic layer. Further, it can be seen that the characteristics are further improved by performing the rapid cooling treatment continuously with the post heat treatment.

Example 3 Table 4 shows Example 1 except that various materials were used for the intermediate layer and the film thickness was 30 nm.
Of the magnetic layer of the magnetic recording medium manufactured in the same manner as
It is the result of putting together the half width Δθ ₅₀ values of the rocking curve obtained by the X-ray diffraction method for the (002) diffraction line. In addition,
For comparison, the case where Ta and Cr having a body-centered cubic (bcc) structure are used as the intermediate layer is also shown.

[0042]

[Table 4]

From this table, as compared with the case of using Ta or Cr having the bcc structure as the non-magnetic underlayer, Δθ ₅₀ is improved when various materials having the hcp structure are used, and the crystal orientation control of the magnetic layer is controlled. You can see that it is done effectively.

(Example 4) In the manufacturing method described in Example 1, a Ta target was used between the non-magnetic substrate and the soft magnetic backing layer to form a Ta first underlayer of 5 nm and NiFeC.
2n of NiFeCr second underlayer using r target
A magnetic recording medium was manufactured in the same procedure as in Example 1 except that the magnetic domain control layers of m and IrMn were formed to a thickness of 10 nm.

No particular difference was observed in the magnetic characteristics and SNR between the perpendicular magnetic recording medium manufactured by this method and the perpendicular magnetic recording medium manufactured by the method of Example 1.

FIG. 3 is a comparison of the output waveforms for one round by the spin stand tester of the perpendicular magnetic recording medium produced by each of these methods. In the perpendicular magnetic recording medium manufactured by the method shown in Example 1 having no structure of the underlayer and the magnetic domain control layer, spike noise is unevenly generated over the entire circumference, whereas the underlayer and the magnetic domain control It can be seen that the spike noise is remarkably reduced by the configuration including the layers. This is because by providing the underlayer and the magnetic domain control layer on the non-magnetic substrate, the magnetic domain wall is not formed in the soft magnetic backing layer laminated subsequently to these layers.

[0047]

As described above, in the perpendicular magnetic recording medium of the present invention, the magnetic layer for magnetic recording is composed of two layers, and the first magnetic layer on the nonmagnetic substrate side is made of the nonmagnetic material. The grain boundary is made of a CoCr-based alloy having a granular structure consisting of a metal oxide or a nitride, and the second magnetic layer provided thereon is a non-magnetic grain boundary containing no metal oxide or nitride. It is composed of a CoCr-based alloy having a granular structure. Among these magnetic layers, the first magnetic layer ensures good electromagnetic conversion characteristics due to its granular structure, while the second magnetic layer elutes from the non-magnetic grain boundaries of the first magnetic layer. Since it is configured so as to block incoming Co atoms and ensure high durability of the medium, it has excellent magnetic characteristics and electromagnetic conversion characteristics, and has a high temperature and high humidity environment of 85% and 80% RH. 3 hours in 50 ml of pure water
The value of the amount of Co extracted by rocking for 10 minutes by ICP emission spectroscopy was 10 per 1 m ^{2 of} the disc area.
It is possible to realize a medium which is suppressed to less than μg and has sufficient long-term reliability.

Further, by providing an underlayer consisting of one layer or a plurality of layers and a magnetic domain control layer between the non-magnetic substrate and the soft magnetic backing layer, spike noise generated due to the soft magnetic backing layer is greatly increased. Can be suppressed.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a configuration example of a perpendicular magnetic recording medium of the present invention.

FIG. 2 is a diagram for explaining another configuration example of the perpendicular magnetic recording medium of the present invention.

FIG. 3 is a diagram for explaining an output waveform for one rotation by a spin stand tester of the perpendicular magnetic recording medium of the present invention.

[Explanation of symbols]

11, 21 Non-magnetic substrate 12, 24 Soft magnetic backing layer 13, 25 Middle layer 14, 26 First magnetic layer 15, 27 Second magnetic layer 16, 28 Protective layer 17, 29 Liquid lubricant layer 22 Multilayer underlayer 23 magnetic domain control layer

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01F 10/16 H01F 10/16 41/18 41/18 (72) Inventor Hiroyuki Uesumi Kawasaki, Kawasaki City, Kanagawa Prefecture 1-1-1 Nitta, Tanabe, Fuji Electric Co., Ltd. F term (reference) 5D006 BB02 BB07 BB08 CA01 CA03 CA05 CA06 DA03 DA08 EA03 FA02 FA09 5D112 AA03 AA04 AA05 AA24 BB05 BB06 BD03 FA04 FB20 FB26 5E049 AA04 BA08 GC01

Claims (7)

[Claims] 1. A perpendicular magnetic recording medium in which a soft magnetic backing layer, an intermediate layer, a magnetic layer of a CoCr-based alloy layer, a protective layer, and a liquid lubricant layer are sequentially laminated on a non-magnetic substrate. The magnetic layer includes a first magnetic layer having a granular structure provided on the intermediate layer side and a second magnetic layer having a non-granular structure provided on the protective layer side. A perpendicular magnetic recording medium characterized by: 2. The hexagonal closest packing (hcp) as the intermediate layer.
2. A metal selected from the group consisting of Ti, Re, Ru, and Os having a crystal structure of, or an alloy containing at least one metal selected from Ti, Re, Ru, and Os. The perpendicular magnetic recording medium according to 1. 3. An underlayer on the side of the non-magnetic substrate and a magnetic domain control layer on the side of the soft-magnetic backing layer are sequentially laminated between the non-magnetic substrate and the soft magnetic backing layer. Item 3. The perpendicular magnetic recording medium according to item 1 or 2. 4. A step of forming a soft magnetic backing layer on an unheated non-magnetic substrate, a step of forming an intermediate layer on the soft magnetic backing layer, and a Co having a granular structure on the intermediate layer.
Step of forming a first magnetic layer of a Cr-based alloy layer by a sputtering method, and forming a second magnetic layer of a CoCr-based alloy layer having a non-granular structure on the first magnetic layer by a sputtering method A step of forming a protective layer on the second magnetic layer, and a step of forming a liquid lubricant layer on the protective layer; The gas pressure is 10 mTorr or more, and the gas pressure at the time of forming the second magnetic layer is 15
A method of manufacturing a perpendicular magnetic recording medium, which is equal to or less than mTorr. 5. The method of manufacturing a perpendicular magnetic recording medium according to claim 4, further comprising a step of heat-treating the non-magnetic substrate in a film forming apparatus after forming the second magnetic layer. . 6. The method of manufacturing a perpendicular magnetic recording medium according to claim 5, further comprising a step of rapidly cooling the non-magnetic substrate in a film forming apparatus after the heat treatment of the non-magnetic substrate. 7. The method according to claim 4, further comprising a step of forming an underlayer on the non-magnetic substrate and a step of forming a magnetic domain control layer on the underlayer. A method of manufacturing a perpendicular magnetic recording medium according to claim 1.