JPS6325857A - Magneto-optical disk and its production - Google Patents

Abstract

PURPOSE:To efficiently obtain a magneto-optical disk having excellent corrosion resistance and durability and high reliability by subjecting a specific gaseous mixture to ion implantation to a magnetic recording film to the depth of <=1/2 the film thickness of the magnetic recording film. CONSTITUTION:At least one kind of the element selected from the group of P, As, Se, and at least one kind of the element selected from the group of C, B, Si, Ge, He, Ne, H or at least one kind of the element selected from the group of P, As Se, at least one kind of the element selected from the group of C, B, Si, Ge, He, Ne, H, and at least one kind of the element selected from the group of Mo, W, Cr, Re, Ru are ion-implanted to the depth of 1/2 the film thickness into the surface part of the magnetic recording film consisting of an alloy of rare earth elements and iron family elements or the magnetic recording film consisting of an alloy contg. <=10atomic% at least one kind of the element selected from the group of Ti, Ta, Nb, Al, Zr, Ni, Pt, Rh, Pd by atomic % in the above-mentioned alloy. The film formation is thereby executed at a high speed with good controllability.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magneto-optical disk on which information is written (recorded), reproduced and erased using a laser beam or the like.
In particular, highly durable and reliable magneto-optical disks having magnetic recording films with high corrosion resistance and excellent magnetic and magneto-optical properties, as well as Kerr enhancement films with few film defects and good adhesion to the underlying layer. The present invention relates to a method of manufacturing a highly durable and reliable magneto-optical disk having a dielectric film such as a protective film.

[Conventional technology]

In recent years, magneto-optical disks that are high-speed, high-density, and capable of arbitrarily reading and rewriting large amounts of information have been attracting attention. The magnetic recording materials used in these magneto-optical disks are mainly made of alloys containing rare earth elements and iron group elements.
Various materials are being studied. However, these magnetic recording materials are active in the environment in which they are used and easily react with moisture and oxygen in the air to form hydroxides and oxides on their surfaces. This reaction gradually progresses from the surface of the magneto-optical disk to the inside of the magnetic recording film.
A problem arises in that the magnetic and magneto-optical properties of the magnetic recording film are significantly degraded. This reduces the reliability of the magneto-optical disk, and has been a major obstacle to its practical use.

To date, methods to solve this problem of corrosion of magnetic recording films include (1) improving the corrosion resistance of the A-8 film itself, and (2) providing a protective film on the surface or interface of the magnetic recording film to protect it from outside air. In particular, methods are being considered to block
If the corrosion resistance of the magnetic recording film itself could be improved like the former.

This eliminates the need for the step of providing a protective film, making it possible to simplify the manufacturing process of magneto-optical disks. For this reason, many proposals have been made to improve the corrosion resistance of the magnetic recording film itself, and a representative example is the Japanese Patent Publication No. 60-2121.
No. 7 and Japanese Patent Publication No. 60-26825.

However, improvement in the corrosion resistance of a magnetic recording film and magnetic and magneto-optical properties are in a contradictory relationship, and a magnetic recording film that satisfies both simultaneously has not yet existed.

On the other hand, when manufacturing a magneto-optical disk, for example, in a magneto-optical disk having the structure shown in FIG.
A magneto-optical disk was manufactured by forming a car enhancement film 27, depositing a magneto-optical recording film 28 thereon, and then sequentially laminating a protective film 29 on top of it by sputtering or vacuum evaporation. . However, when forming enhancement films and protective films that are mainly made of dielectric materials, the vacuum evaporation method has weak adhesion to the underlying layer, and the sputtering method destroys or damages the vicinity of the surface of the main layer. There were many problems such as damage, slow film formation rate, and poor controllability of film formation.

[Problem that the invention seeks to solve]

Conventionally, in order to improve the corrosion resistance of the magnetic recording film itself, elements effective for improving corrosion resistance have been added to magnetic recording materials. These additive elements are required to meet the requirements of not degrading magnetic and magneto-optical properties and improving corrosion resistance. However, as described above, the magnetic and magneto-optical properties and the corrosion resistance of the magnetic recording film are contradictory.

That is, although the corrosion resistance is improved by the addition of elements, the magnetic and magneto-optical properties are deteriorated, and conversely, if the deterioration of the magnetic and magneto-optic properties is suppressed, sufficient corrosion resistance cannot be obtained. On the other hand, the vacuum evaporation method used in the prior art is used to form a car enhancement film and a protective film, which are mainly composed of a dielectric material, which constitute a magneto-optical disk.

There are problems such as weak adhesion with the base layer, and in the sputtering method, (1) the base layer is destroyed by plasma;
There were problems such as (2) slow film formation rate and (3) poor controllability of film formation. Furthermore, these film forming techniques have a drawback in that the controllability of film formation is poor and the resulting films lack reproducibility.

An object of the present invention is to provide a highly durable and reliable magneto-optical disk having a highly corrosion-resistant magnetic recording film without deteriorating its magnetic and magneto-optical properties, and a magnetic enhancement film or protective film constituting the magneto-optical disk. When forming dielectric films such as, it does not destroy the underlying layer, has few film defects, has good adhesion to the underlying layer, and has durability that allows film formation to be performed at high speed and with good control. An object of the present invention is to provide a method for manufacturing a magneto-optical disk which is excellent in reliability and has high reliability.

[Means for solving problems]

The object of the present invention is to provide a magnetic recording film made of an alloy of a rare earth element and an iron group element, or an atomic %
So, Ti, Ta, Nb, A11. Zr, Ni
A magnetic recording film made of an alloy containing at least one element selected from the group consisting of , Pt, Rh, and Pd at atomic percent or less of IO, on the surface of the magnetic recording film in order to block oxygen or moisture in the atmosphere. At least one element selected from the group of P, As, and Se, which is an element that forms a stable passive state and an element that promotes oxidation of the surface portion of the magnetic recording film, and C, B, SL, Ge, At least one element selected from the group of He, Ne, H, or P, As, Se
at least one element selected from the group of C, B, S
At least one element selected from the group consisting of i, Ge, He, Ne, and H and at least one element selected from the group consisting of Mo, W, Cr, Re, and Ru are added to the magnetic recording film. , by ion-implanting the above elements to a depth of 1/2 or less of the film thickness.

achieved.

In the ion implantation method of the present invention, ions are ejected from a target made of the element of the ions to be implanted, and an ionization energy of 10 to 50 kaV is applied to the ions using an accelerator, so that ions are ionized at 1 x 1016 ions/cd to 3 x 1017 a/cd.
It is preferable to set the ion implantation amount to cJ.

In this case, the depth of ion implantation into the magnetic recording film can be freely controlled by changing the ion acceleration voltage, and since this ion implantation process is low temperature, a substrate with low heat resistance such as plastic is used. In addition, ion implantation can be performed with good purity of implanted elements, controllability, and reproducibility.

The present invention also provides a magnetic recording film made of an alloy of rare earth elements and iron group elements containing Ti, Ta, which are elements that react with oxygen and nitrogen to form stable oxides or nitrides.
Nb, A11. Zr, Ni, Cr, Mo.

At least one metal element selected from the group W and oxygen, nitrogen, or a mixed gas thereof at the same time.

Ions are implanted to a depth of 1/2 or less of the thickness of the magnetic recording film, or after the above metal elements are ion-implanted, oxygen, nitrogen, or a mixture thereof is added to a depth of 1/2 of the thickness of the magnetic recording film. ion implantation to a depth of 2 or less, or the above-mentioned stable oxide or nitride forming elements such as Ti, T.
At least one metal element selected from the group consisting of a, Nb, An, Zr, and Ni is applied to the magnetic recording film in advance.
The object of the present invention can be achieved by ion-implanting oxygen, nitrogen, or a mixed gas of these to a depth of 1/2 or less of the thickness of the magnetic recording film. can.

The ion implantation method of the present invention is similar to the method described above, in which implanted ions are ejected from a target, ionization energy in the range of 10 to 50 kaV is applied by an accelerator, and 1×10”/d to 3×10” ions/ It is preferable to set the ion implantation amount to d. In order to oxidize or nitride the implanted metal element ions to form a stable oxide or nitride, the conditions for introducing oxygen, nitrogen, or a mixed gas thereof are such that the gas pressure is I x 10-
” It is preferable to perform ion implantation in the range of 5 × 10-' Torr, and these oxygen,
The depth of ion implantation of nitrogen or a mixture of these gases can be freely controlled by changing the ion accelerating voltage, and since the process allows ion implantation at low temperatures, it is possible to control the depth of ion implantation using low heat resistant materials such as plastics. In addition, ion implantation can be performed with good controllability and reproducibility.

The depth at which the passivation element, oxide, or nitride forming element is implanted by ion implantation into the magnetic recording film of the present invention is such that even if the ion implantation depth is very small, the corrosion resistance can be improved. It does occur.

If the depth exceeds 1/2 of the thickness of the magnetic recording film, the magnetic and magneto-optical properties of the magnetic recording film itself will deteriorate, so the ion implantation depth is preferably 1/2 or less of the thickness of the magnetic recording film. .

Further, the present invention provides a magnetic recording film made of an alloy of rare earth elements and iron group elements, or the above alloy, with T
i, Ta, Nb, AQ, Zr, Ni, Pt.

A magnetic recording film made of an alloy containing at least one element selected from the group of Rh and Pd is subjected to surface treatment such as heat treatment of the magnetic recording film in an atmosphere containing oxygen, nitrogen, or a mixed gas thereof.

An element that forms a stable nitride layer or oxide layer or a mixed layer of nitride and oxide on the surface, or an element that forms the above-mentioned stable passivity, an element that promotes surface oxidation, or a stable nitride; After ion-implanting an element that forms an oxide, the surface is subjected to surface treatment such as heat treatment in an atmosphere containing oxygen, nitrogen, or a mixed gas of these to form a nitride or oxide layer with superior corrosion resistance. Two objects of the present invention can be achieved by forming a mixed layer of nitride and oxide.

Furthermore, Si3N4 and TiN are used as car enhancement films, protective films, etc. that constitute magneto-optical disks.

As a source gas when forming a dielectric film such as 5iO1SiO, Tie, etc.

For 5L3N, SiH, and NH, etc. For TiN, TiC island, and NH, etc. For Si○, SiH,
and H2, and 02 or N20, etc., for SiO, SiH4 and 02, etc., for TiC2, TiCl14
and H, O, etc. to lower the substrate temperature (preferably 90°C).
For example, laser-excited chemical vapor deposition (L-
The object of the present invention can be achieved by forming a film by a CVD method. That is, according to the L-CVD method, the underlying layer of the dielectric film to be formed is not destroyed or damaged, and there are fewer film defects.

Moreover, it has good adhesion with the underlayer, and can be formed at high speed and with good controllability. It also has good magnetic and magneto-optical properties, and is highly reliable in terms of corrosion resistance and durability. You can get a good deal.

[Effect]

In the present invention, in order to form a passive film on the surface of the magnetic recording film, element groups such as P, As, Se, C, B, S
Element groups such as i, Ge, He, Ne, H, Mo, W, C
At least one passivating element and surface oxidation promoting element selected from the group of elements such as r, Re, Ru, etc.
Either ions are implanted into the surface layer of the magnetic recording film, or Ti, Ta, Nb, Al, Zr, etc. are added to the magnetic recording film in advance.
When a passivating element such as Ni, Pt, Rh, or Pd or a noble metal element is contained, and a surface oxidation promoting element is ion-implanted into the passivating element, the passivating element becomes a magnetic recording film due to the action of the surface oxidizing promoting element. These elements form a passive film of oxide on the surface of the magnetic recording film. This passive film covers the surface of the magnetic B film densely and uniformly.

The magnetic recording film will be completely shielded and protected from the atmosphere. In addition, when ion-implanting the above elements into the magnetic recording film, the depth of the ion implantation can be freely controlled by the ion implantation energy, and the implanted elements can reach the recording surface side of the magnetic recording film. Since the magnetic recording film is not heated or the magnetic recording film is not heated, the corrosion resistance can be improved without deteriorating the magnetic and magneto-optical properties.

In addition, in the present invention, elements that form stable oxides or nitrides in the magnetic recording film, such as Ti,
Ta, Nb, An, Zr-Ni, Cr, Mo.

Containing at least one metal element such as W,
A gas containing one or more of oxygen and nitrogen is ion-implanted into this magnetic recording film, or a magnetic recording film that does not contain the above-mentioned oxide or nitride-forming elements is implanted with the above-mentioned metal element and the above-mentioned gas. When ions are simultaneously implanted, or when the above metal elements are ion-implanted and the above-mentioned gases are ion-implanted after that, a stable and dense oxide layer, nitride layer, or a mixture thereof is formed near the surface of the magnetic recording film. A layer is formed that blocks oxygen, moisture, etc. in the atmosphere and protects the magnetic recording film, resulting in a marked improvement in corrosion resistance. On the other hand, since the depth of ion implantation of the metal elements and gases mentioned above can be freely controlled as described above, the depth of the ion implantation layer is 1 part of the thickness of the magnetic recording film.
Since it can be strictly controlled to less than /2, the magnetic and magneto-optical properties of the magnetic recording film are not deteriorated.

Furthermore, in the present invention, a magnetic recording film made of an alloy of a rare earth element and an iron group element, a magnetic recording film containing the above-mentioned passivating element, oxide or nitride-forming element, or the above-mentioned ion implantation process is performed. It is also possible to perform heat treatment or surface treatment on the magnetic recording film in an atmosphere containing oxygen, nitrogen, or a mixture of these gases.
An Ht-dense protective film similar to that described above can be formed on the surface of the magnetic recording film, and thereby the corrosion resistance can be further improved without deteriorating the magnetic and magneto-optical properties of the magnetic recording film.

Furthermore, when producing the magneto-optical disk of the present invention, it is necessary to heat the substrate temperature to a high temperature of 400° C. or higher using normal chemical vapor deposition when forming a car enhancement film, a protective film, etc. However, in the present invention, a film can be formed at a substrate temperature of 90° C. or lower by using a laser-excited chemical vapor deposition method (L-CVD method) using a high-energy laser beam as the excitation energy of the source gas. Therefore, it becomes possible to use an inexpensive polymeric material that does not take heat resistance into consideration for the substrate or medium constituent material. Furthermore, by using the L-CVD method of the present invention, the adhesive strength between the underlayer or the substrate can be significantly improved without damaging the underlayer or the surface of the substrate. Using this L-CVD method, it is possible to form films at high speed and with good controllability, making it possible to produce magneto-optical disks with good reproducibility and high efficiency, and with excellent corrosion resistance and durability. A highly reliable and high performance magneto-optical disk can be obtained.

〔Example〕

An embodiment of the present invention will be described below in more detail with reference to the drawings.

(Example 1) A magneto-optical disk was manufactured as follows. First, Tb2. Fe,
4Go, a magnetic recording film having a composition of 0.1. It was formed by sputtering to a film thickness of . The conditions at this time were: Ar was used as the discharge gas, and the discharge gas pressure was 5 x 10"T.
orr, input RF (high frequency) power density 1.1W/cJ,
Sputtering time was 5 minutes. Subsequently, Cr, W, Mo, Re, and Ru were deposited on this magnetic recording film by ion implantation.
, and then PlB or P, C, and B. The depth of participation at this time was 150 people. The characteristics of the magneto-optical disk prepared in this way are that the Kerr rotation angle θk
was 0.33 degrees, coercive force He was 4.0 kOe, and Curie temperature Tc was 200 degrees Celsius. In addition, when the operating characteristics of this magneto-optical disk were measured, the C/N (carrier-to-noise ratio) was 50 dB (laser output cuff mW, external magnetic field 20 dB).
00e). No difference was observed in these characteristics compared to the case of a magnetic recording film made only of TbFeCo, which does not use the present invention.

Next, a life test of this magneto-optical disk was conducted. The lifespan is evaluated at a high temperature of 80℃ and a relative humidity (RH) of 95%.
This was done by measuring the change in saturation magnetization over time when this disk was stored in a high humidity environment and the change in Kerr rotation angle over time measured from the recording surface side. The results are shown in FIG. In the figure, the storage time (hours) is plotted on the horizontal axis, and the rate of change (%) in saturation magnetization Ms and Kerr rotation angle θ is plotted on the vertical axis as relative values when the initial value is set to 100. first,
In the case of only T b Fe Co, the saturation magnetization Ms increases with time as shown in curve 1, and reaches 50
After 0 hours, the increase was approximately 90% of the initial value. On the other hand, 1
By the ion implantation method of the present invention, Cr or Mo is added to P.
, C or P, C, B made by implanting T b F
e In the case of Co film, as shown in curve 3, the saturation magnetization M
The change in s was significantly small, about 5%. Further, the change in Kerr rotation angle θ increased by about 20% after 500 hours in the case where the present invention was not used.

On the other hand, there was no change in θ of the magneto-optical disk manufactured by the method of the present invention.

From the above results, the corrosion resistance of the magnetic recording film for a magneto-optical disk produced using the method of the present invention was able to be significantly improved compared to the magnetic recording film produced using the conventional method.

(Example 2) A magneto-optical disk was manufactured using the same method as in Example 1. That is, T is placed on the cleaned circular disk substrate.
b2. Fe5. Go, X, (X=Ti, Ta.

A 0 and 1p magnetic recording film having a composition of Nb, Ni) was formed by sputtering. The sputtering conditions at this time are the same as in Example 1. Subsequently, P, SL, As, Ge, Se, and B were implanted by ion implantation onto this magnetic recording layer 8m, and the implantation depth at this time was 200 m.
As a person. The characteristics of the magneto-optical disk produced in this way are θ = 0.30''.

He = 3.0 kOe, Tc = 180°C. In addition, when we measured the operating characteristics of this magneto-optical disk, we found that
C/N=51 dB. These characteristics showed no difference from those of a magneto-optical disk having a magnetic recording film manufactured without using the present invention.

After measuring the characteristics, this disk was subjected to a life test in the same manner as in Example 1. The results are shown in Figure 2. In Figure 1, the horizontal axis shows the storage time (hours), and the vertical axis shows the rate of change (%) of the saturation magnetization Ms, relative to the initial value of 100. Ta. First, in the case of a magnetic recording film manufactured without using the ion implantation method of the present invention, the saturation magnetization Ms
The change in is shown in curve 5.6. Curve 5 shows T on the magnetic recording film.
b When F e Co N i is used, curve 6 is T
This is the case of bFeCoX (X=Ti, Ta, Nb).

In the conventional method, Ti and Ta are used to improve corrosion resistance.

When Nb and Ni are added, the rate of change in saturation magnetization increases from 92% to N.
The case of i is suppressed to 57%, and the other cases are suppressed to 23%. On the other hand, in the magnetic recording film produced using the ion implantation method of the present invention, curve 7 shows that TbFeCo
This is the case when Ni is used, and curve 8 is TbFeCoX (
In the case of X=Ti, Ta, Nb), the rate of change in saturation magnetization was 15% and 5%, respectively, which was significantly suppressed compared to the conventional method.

(Example 3) A magneto-optical disk was manufactured using the same method as in Example 1. That is, Tb, a are deposited on the cleaned circular disk substrate.
A 0,1- magnetic recording film having a composition of Fe, Go, X (X=Rh, Pt, Pd) was formed by sputtering. The sputtering conditions at this time are the same as in Example 1. Subsequently, P was deposited on this magnetic recording film by ion implantation.
, C, and B were injected.

At this time, the energy was controlled so that the depth of impact was 100 people. The characteristics of the magneto-optical disk produced in this way are θ=o, 3Q°, Hc=5.0kOa, Tc
= 180°C. Further, when the operating characteristics of this magneto-optical disk were measured, it was found that C/N = 50 dB. The characteristics of these magneto-optical disks were no different from those using magnetic recording films prepared without using the method of the present invention.

After measuring the magnetic properties, the life test of this disk was carried out in Example 1.
The results are shown in Figure 3, where the horizontal axis represents the storage time (hours) and the vertical axis represents the saturation magnetization M.
The change rate (%) of s is shown as a relative value when the initial value is 100. First, curve 9 shows the change in saturation magnetization Ms in the case of a magnetic recording film manufactured without using the ion implantation method of the present invention. In the conventional method, Rh is added to improve corrosion resistance.

The change in saturation magnetization when adding Pt and Pd is 80°C
, initial 1.95 when stored for 500 hours in 95% RH.
doubled. On the other hand, in the magnetic recording film produced by the ion implantation method, as shown in curve 10, S
It increased 1.10 times after OO hours. Thus, it was found that the magnetic recording film of the present invention can significantly suppress changes in saturation magnetization.

(Example 4) A magneto-optical disk was manufactured using the same method as in Example 1. That is, T is placed on the cleaned circular disk substrate.
b1. Fe,, Co, X (X=Zr, AfL, Ti
, Ta) and a thickness of 0.1 layer was formed by sputtering. The sputtering conditions at this time are the same as in Example 1. Subsequently, P, B, and C were implanted onto this magnetic recording film by ion implantation. The energy was controlled so that the depth of impact at this time was 150 people. Then heated N2 or 02 or Oa/
Surface treatment was performed for 10 minutes at A r = 30/70. When we measured the magnetic properties of the magneto-optical disk produced in this way, we found that θ = 0.30'', Hc
= 5.0 kOe, Tc = = 190°C. Also,
When we measured the operating characteristics of this magneto-optical disk, we found that C/
N=48 dB. No differences were observed in the characteristics of these magneto-optical disks due to differences in manufacturing methods.

After measuring the magnetic properties, a life test of the disk was conducted in the same manner as in Example 1, and the results are shown in FIG. In the figure, the horizontal axis shows the storage time (hours), and the vertical axis shows the rate of change (%) of the saturation magnetization Ms as a relative value when the initial value is 100.

First, curves 11.12 show changes in saturation magnetization Ms in the case of a magnetic recording film manufactured without using the ion implantation method of the present invention. TbFeCoX (
The change in saturation magnetization of X=Zr, AQ) is.

As shown in curve 11, it increased by 1.4 times after being left for 500 hours. In addition, TbFeCoX (X
= Ti, Ta) is 1.2 as shown in curve 12.
It has doubled. In contrast, curve 13 shows the change in saturation magnetization of the magnetic recording film manufactured using the ion implantation method of the present invention.
．． A curve 13 shown in 14 is T b Fe Co X
(X=Zr, M) film, and curve 14 shows the change in Ms of the TbFaCoX (X=Ti, Ta) film by 15% and 5%, respectively, and saturation magnetization by using the present invention. It was found that changes in can be significantly suppressed.

(Example 5) A magneto-optical disk was manufactured according to the procedure i described below. Tb, FeG4Co, or Tb, □Fe, on a cleaned glass or resin circular disk substrate.
,Go,. A magnetic recording film having a composition as follows was formed to a thickness of 0.1 by sputtering. The conditions at this time are Ar
is used as the discharge gas, and the discharge gas pressure is 5 × 10-'
Torr, input RF power density 1. lW/cd and sputter time was 5 minutes. Note that the substrate was water-cooled during sputtering. Ni, Ni,
Cr, Mo, W, Nb, or Zr and oxygen were implanted, and the implantation depth at this time was 150 people. The characteristics of the magneto-optical disk produced in this way are that the Kerr rotation angle θk is 0.35 to 0.38χ degrees, the coercive force Hc is 5.0 kOe, and the Curie temperature Tc is 2.
It was 00℃. Also, when we measured the operating characteristics of this magneto-optical disk, we found that C/N (carrier-to-noise ratio) =
50 to 53 dB (laser output cuff mW, external magnetic field 2000
e). No difference was observed in these properties compared to the case of using only T b Fe Co without using the present invention.

Next, a life test of this magneto-optical disk was conducted. Disc life evaluation is performed at a temperature of 80°C and relative humidity (RH).
This was done by measuring the change in saturation magnetization over time when the manufactured disk was stored in a high temperature and high humidity environment with a temperature of 95%. The results are shown in FIG. In the figure,
The horizontal axis shows the storage time (hours) of the disk in a high temperature and high humidity environment.
, the vertical axis shows the rate of change (%) of the saturation magnetization Ms, and the initial value is 1.
It is shown as a relative value when set to 00. First, TbFeCo
As shown in curve 15, the change in saturation magnetization increased over time, and after 500 hours, the change in saturation magnetization increased by 90% of the initial value. On the other hand, T b produced by ion implantation of Mo, W, or Zr and oxygen
The change in saturation magnetization of the Fe Co film increased by 25% after 500 hours, as shown in curve 16.

Furthermore, the change in saturation magnetization of the magnetic recording film produced by ion implantation of Cr or Nb and oxygen increased by only 6% after 500 hours, as shown by curve 17.

From the above results, the corrosion resistance of the magnetic recording film of the magneto-optical disk produced using the method of the present invention can be significantly improved compared to the film produced using the conventional method. It can be seen that this is effective in improving corrosion resistance without deteriorating properties.

(Example 6) The method for manufacturing a magneto-optical disk is the same as in Example 5. That is, on a circular disk substrate, Tb2°F e G4
A magnetic recording film having a composition of Co@s or Tb, Fe, Co1° was formed to a thickness of 0.1° by sputtering. The sputtering conditions at this time are the same as in Example 5. Subsequently, Ti, Ta, or M and nitrogen were implanted onto the magnetic recording film by ion implantation. The depth of penetration at this time was controlled to 150 people.

The characteristics of the magneto-optical disk produced in this way are as follows: θ=0.35' to 0.3g', Hc=5.0kOe
, Tc=200°C. Further, when the operating characteristics of this disk were measured, the C/N was 50 to 53 dB.

These properties are similar to those of TbFe prepared without using the present invention.
There was no difference from the Co film.

Next, a life test was conducted on the manufactured disk.

The test method was the same as in Example 5, and the results are shown in FIG. The rate of change (%) in saturation magnetization when stored for 500 hours in an environment of 80° C. and 95% RH is approximately 90% for the T b Fe Co film produced without using the present invention (curve 15). increased. On the other hand, when M and nitrogen were implanted into the T b Fe Co film produced using the method of the present invention (curve 18), there was an increase of about 20%, and when Ti or Ta and nitrogen were implanted, there was an increase of about 20%. (Curve 19) There is no difference between the two.8
%, and the rate of change in saturation magnetization was significantly small.

From the above results, by using the method of the present invention, the corrosion resistance of the magnetic recording film could be significantly improved without deteriorating the magnetic and magneto-optical properties.

(Example 7) The method for manufacturing a magneto-optical disk is the same as in Example 5. That is, Tb, on a circular disk substrate.

Fe5sCosXs (X=Ti, Ta, Nb,
A magnetic recording film having a composition of An, Zr, or Ni was formed to a thickness of 0.1 - by sputtering. The sputtering conditions at this time are the same as in Example 5. continue,
Nitrogen or oxygen was implanted onto the magnetic recording film by ion implantation. The depth of participation at this time was 250 people. The characteristics of the magneto-optical disk produced in this way are that θ=0
．． 32' ~ 0.35', He = 3.0 kOe,
Tc was completed.

(Example 8) The method for manufacturing a magneto-optical disk is the same as in Example 5. That is, Tb2sFe5. Co
, Xs (X=Ti, Ta, Nb, A(L, Z
A magnetic recording film having a composition of 0.
It was formed by sputtering to a film thickness of 1-. The sputtering conditions at this time are the same as in Example 5. Subsequently, 0□, N2. or 02/Ar=40
/60 at a flow rate of 1oon+Q/min to oxidize or nitride the surface of the magnetic recording film for about 1 hour. The characteristics of the magneto-optical disk produced in this way are: θb=0.32” to 0.35°, Hc=3.0k
oe, Tc = 180°C. When the operating characteristics of this disk were measured, the C/N was 49 dB. These characteristics were no different from those of the magnetic recording film prepared without using the method of the present invention.

Next, a disk life test was conducted using the same method and conditions as in Example 5. The results are shown in Figure 8.
The rate of change (%) in saturation magnetization Ms when stored for 500 hours in an environment of ℃ and 95% RH is the same as that of T b Fe Co X (X = A) prepared without using the present invention.

In the case of the Zr or Ni) film, it increased by 40% as shown in curve 1 20. On the other hand, the magnetic recording film surface-treated with oxygen or nitrogen of the present invention has 12
% increase and decreased significantly. Also, T b Fe C
o X (X = Ti, Ta, Nb)
In the case of membranes, there was a large decrease of 5% from an increase of 15%, as shown in curve 21.25.

Thus, by using the method of the present invention, the corrosion resistance of the magnetic recording film could be significantly improved without deteriorating the magnetic and magneto-optical properties.

(Example 9) FIG. 9 shows a schematic diagram of the cross-sectional structure of a produced magneto-optical disk which is an example of the present invention. The magneto-optical film was produced using an in-line CVD-vacuum deposition-sputtering device. That is, on the cleaned disk substrate 26,
First, using 1% SiH4, 5% NH, and the remainder Ar as a source gas, a laser-induced chemical vapor deposition method (
Car enhance $21 was formed by L-CVD method). The film thickness was set at 1,200 people. After that, (Gd1.5Tba, 4)a, 2
z (Fe,,5Coo,l). ,7. A magnetic recording film 28 having a composition of 1 was formed. The sputtering conditions at this time were: Ar was used as the discharge gas, and the sputtering gas pressure was 5 x 1.
0-' Torr, input RF high power W/aJ, sputtering time 4 minutes, and film thickness 1000. Subsequently, a protective film 29 was formed by the L-CVD method. The CVD conditions at this time are the same as in the case of forming the car enhancement film 27 previously.

The characteristics of the magneto-optical disk produced in this way are that the Kerr rotation angle θk is 0.85 degrees, the coercive force He is 5.0 koe,
The Curie temperature Tc was 200° C., and the C/N (carrier-to-noise ratio) was 54 dB. The production of this disk was repeated 10 times, and it was found that the variation in each magneto-optical property was ±2%, which was significantly smaller than ±7% when the film was formed by the conventional all-sputtering method. In addition, when measuring the density of film defects such as pinholes, it was found that a film with a thickness of 1,000 people formed by the L-CVD method was 1 x 102 defects/d, compared to the density of film defects formed by the sputtering method.
The defect density could be significantly reduced compared to Xl0' pieces/d. In addition, since film formation by the L-CVD method is a low-lying film formation, the internal stress is smaller at around 1710 compared to conventional sputtering methods and vacuum evaporation methods, and the adhesiveness of the film is less than 100% when tested with a tape test. -It was found that the adhesion was significantly improved, as some peeling occurred in the conventional method, whereas it did not occur at all in the CVD method.

By using the L-CVD method in this way.

It was found that compared to conventional methods, stable film formation was possible, fewer film defects were observed, internal stress was reduced, adhesion to the underlying layer was improved, and film formation speed was increased.

(Example 10) The structure of the produced magneto-optical disk is as shown in FIG. 9, and is the same as in Example 9 except that SiO is used for the car enhancement film 27 and the protective film 29.

The formation of SiO 11% is based on SiH 41% as the source gas.
, H, 4%, 021%, He balance, or SiH41%
Using 3N40 1% and the remainder of He, the pressure inside the reaction tube was 3To.
The L-CVD method was performed at a substrate temperature of 80° C. and a reaction time of 2 minutes. The thickness of the SiO films formed was 1,200 for the car enhancement film 27 and 1,500 for the protective film 29.

The characteristics of the magneto-optical disk produced in this way are as follows: θ = 0.90', Hc = 5.0 kOe, Tc = 20
The temperature was 0° C. and the C/N was 55 dB. Although this disk was manufactured repeatedly, the variation in characteristics was ±3%.
This was significantly smaller than the ±8% variation in discs produced by the conventional method. Further, internal stress and adhesion to the base layer were the same as in Example 9.

(Example 11) The structure of the produced magneto-optical disk is as shown in FIG. 9, and is the same as in Example 9 except that SL and N4 are used for the car enhancement film 27 and SiO2 is used for the protective film 29. Also, S
i. The conditions for forming the N4 film are the same as in Example 9. SiO
2 pancreatic formation using SiH41%, 0.2% as source gas.
%, Ar balance, reaction pressure 5 Torr, substrate temperature 8
The L-CVD method was carried out at 0°C for a reaction time of 2 minutes.

The thickness of each layer is 1,200 for the car enhancement film 27 and 1,500 for the protective film 29.

The characteristics of the magneto-optical disk produced in this way are θh
=0.85', Hc=5kOe, Te=200℃, C
/N=54 dB. The same results as in Example 9 were obtained regarding the reproducibility of disk characteristics, internal stress, and adhesion.

(Example 12) The structure of the manufactured magneto-optical disk is as shown in FIG.
The same procedure as in Example 9 was carried out except that . Ti
The O2 film was formed using TiC1141% as a source gas,
H, 01%, Ar balance was used. Here, Tic:Q
, and H, O are liquid at room temperature, so TiC11
, and TiCQ by bubbling Ar in H,O,
and H and O were included. In addition, the concentration can be adjusted using T1Cf
This was done by changing the temperature of 14 or H2O and changing the vapor pressure. L-CVD conditions; pressure is 5 Torr, substrate temperature is 90° C., and reaction time is 2 minutes.

The characteristics of the magneto-optical disk manufactured in this way are as follows: θ = 0.80', Hc = 5.0 kOe, Tc = 200
℃, C/N=53 dB. Here, the film thickness of the car enhancement film 27 is 1200 mm, and the film thickness of the protective film 29 is 1500 mm. It was almost the same.

(Example 13) The structure of the produced magneto-optical disk is as shown in FIG. 9, and is the same as in Example 9 except that TiN is used for the car enhancement film 27 and the protective film 29.

Formation of TiN[TiCEL, 1% as source gas
.

NH, 5%, balance Ar was used. The TiC concentration was adjusted using the same method as in Example 12. The L-CVD conditions are the same as in Example 12, pressure 5 Torr, substrate temperature 90°C.
, reaction time is 2 minutes.

The characteristics of the magneto-optical disk produced in this way are: θ = 0.87', He = 5 kOe, Tc = 200°C, C
/N=54dB. Here, the thickness of each layer is

1200 people for car enhancement film 27, 15 people for protective film 29
There are 00 people. The reproducibility of disk characteristics, internal stress, and adhesion after repeated manufacturing were the same as in Example 9.

〔Effect of the invention〕

As explained in detail above, a magnetic recording film in which a passivating layer is formed by ion-implanting a passivating element and an oxidation-promoting element into the surface portion of the magnetic recording film constituting the magneto-optical disk of the present invention, or A magnetic recording film in which a stable oxide or nitride protective film is formed by ion-implanting oxygen, nitrogen, or a mixture of these gases, or by surface treatment in the above-mentioned gas atmosphere, is Furthermore, since the corrosion resistance can be significantly improved without deteriorating the magneto-optical properties, a magneto-optical disk having excellent performance with high durability and reliability can be obtained.

Further, in this case, since it is not necessary to form another protective film on the magnetic recording film, the structure of the magneto-optical disk can be simplified and the manufacturing process can also be simplified.

By using the L-CVD method of the present invention in the formation of various films constituting magneto-optical disks, it is possible to form films at low temperatures, which reduces the internal stress of the film and has high energy. Since the particles do not collide with the substrate or the underlying layer, there is no destruction or damage to the substrate or the underlying layer, and even though the film is formed at low temperatures, the adhesive strength with the substrate or underlying layer is stronger than that of conventional methods. Furthermore, the source gas is supplied with sufficiently large excitation energy by laser light, the film formation rate is high, the reaction controllability and uniformity are excellent, and the reproducibility of film formation is significantly improved, so film defects are reduced. It is possible to produce two highly reliable magneto-optical disks that have good corrosion resistance and durability, have excellent magnetic and magneto-optical properties, and have a small amount of high-quality car enhancement films and protective films.

[Brief explanation of drawings]

FIG. 1 is a graph showing the rate of change over time in the saturation magnetization and Kerr rotation angle of the magnetic recording film of Example 1 of the present invention, and FIG. 2 is a graph showing the rate of change over time of the saturation magnetization of the magnetic recording film of Example 2. , FIG. 3 is a graph showing the rate of change over time of the saturation magnetization of the magnetic recording film of Example 3, FIG. 4 is a graph showing the rate of change over time of the saturation magnetization of the magnetic recording film of Example 4, and FIG. 12 is a graph showing the rate of change over time in saturation magnetization of the magnetic recording film of Example 5. FIG. 6 is a graph showing the change over time in the saturation magnetization of the magnetic recording film of Example 6, FIG. 7 is a graph showing the change over time in the saturation magnetization of the magnetic recording film of Example 7, and FIG. FIG. 9 is a graph showing the change over time in the saturation magnetization of the magnetic recording film, and is a schematic diagram showing the structure of the magneto-optical disks manufactured in Examples 9 to 13. 1=Ms change in TbFeCo film 2...Change in θ of TbFeCo film 3...Ms change in ion-implanted TbFeCo film 4.
... Change in θ of ion-implanted TbFeCo film 5-Tb
FeC:oNi film 6-TbFeCoX (X=Ti, Ta, Nb) tl
i7...Ion-implanted TbFeCoNi film 8...
Ion-implanted TbFeCoX (X=Ti, Ta, N
b) Membrane 9: TbFeCoX (X=Pd, Rh, Pt) Membrane 10: Ion-implanted TbFaCoX (X=Pd
, Rh, Pt) film 1l-TbFeCoX (X=Zr, AQ) film 12
・=TbFeCoX (X=Ti, Ta) film 13 ・
...Ion-implanted TbFeCoX (X=Zr, Aa
) Crotch 14-...Ion-implanted TbFeCoX (X=Ti
, Ta) Film 15 = TbFeCo film 16...TbFeCo film 17 into which Mo, W or Zr and oxygen were ion-implanted...Tb into which Cr or Nb and oxygen were ion-implanted
b Fe Co film 18...TbFeCo into which All and nitrogen were ion-implanted
Film 19...Tb Fe Co film 2O-TbFeCoX (X=AQ, Zr or Ni) into which Ti or Ta and nitrogen were ion-implanted
%21=4'bFeC:oX (X = Ti, Ta
or Nb) film 22...T b Fe C implanted with oxygen or nitrogen ions. X (X=Au, Zr or Ni) film 23...T b Fe C implanted with oxygen or nitrogen ions. X (X=Ti, Ta or Nb) film 24...TbFeCoX surface treated with oxygen or nitrogen (X=ship,
Zr or Ni) film

Claims (1)

[Claims] 1. An alloy of a rare earth element and an iron group element, or an alloy of a rare earth element and an iron group element containing Ti, Ta, Nb, Al, Z
In a magneto-optical disk having a magnetic recording film made of an alloy containing 10 atomic % or less of at least one element selected from the group of Pd, Ni, Pt, Rh, and Pd, the magnetic recording film is A magneto-optical disk characterized in that it has a magnetic recording film on which a corrosion-resistant protective film is formed with a depth of 1/2 or less of the film thickness. 2. The corrosion-resistant protective film provided on the magnetic recording film is P, As, S.
At least one element selected from the group e and C, B
, Si, Ge, He, Ne, at least one element selected from the group H, or at least one element selected from the group H selected from the group P, As, Se, and Mo, W, Cr. , Re, and Ru, the corrosion-resistant protective film is formed by ion-implanting at least one element selected from the group consisting of , Re, and Ru into a magnetic recording film using an ion implantation method. magneto-optical disk. 3. Before forming a corrosion-resistant protective film on the magnetic recording film by ion implantation, or after forming the above-mentioned corrosion-resistant protective film, a gas containing at least one of oxygen and nitrogen, or containing any of the above gases. Claims 1 or 2, characterized in that the magnetic recording film has a magnetic recording film on which a corrosion-resistant protective film made of oxide, nitride, or a mixture thereof is formed by surface treatment in a diluted gas atmosphere. Magneto-optical disk described. 4. A magnetic recording film made of an alloy of rare earth elements and iron group elements is coated with a gas containing at least one of oxygen and nitrogen, and Ti, Ta, Nb, Al, Zr, Ni, Cr, Mo,
At least one metal element selected from the group of W is simultaneously ion-implanted into the magnetic recording film by an ion implantation method, or after the metal element is ion-implanted,
Claim 1, characterized in that it has a corrosion-resistant protective film formed by ion-implanting the above gas into a magnetic recording film.
Magneto-optical disk as described in Section. 5. Ti, Ta, and N are added to the alloy of rare earth elements and iron group elements.
b. A gas containing at least one of oxygen and nitrogen is injected into a magnetic recording film made of an alloy containing 10 atomic % or less of at least one metal element selected from the group of Al, Zr, and Ni by ion implantation. 2. The magneto-optical disk according to claim 1, further comprising a corrosion-resistant protective film formed by ion implantation into the magnetic recording film. 6. Before forming a corrosion-resistant protective film on the magnetic recording film by ion implantation, or after forming the above-mentioned corrosion-resistant protective film, a gas containing at least one of oxygen and nitrogen, or containing any of the above gases. According to claim 4 or 5, the magnetic recording film has a magnetic recording film that is surface-treated in a diluted gas atmosphere to form a corrosion-resistant protective film made of oxide, nitride, or a mixture thereof. Magneto-optical disk described. 7. The amount of ion implantation is 1 x 10^1^6 ~ 3 x 10^
The magneto-optical disk according to any one of claims 1 to 6, characterized in that the number of particles is 1^7 pieces/cm^2. 8. Ti, Ta, Nb, Al, Z in alloys of rare earth elements and iron group elements, or alloys of rare earth elements and iron group elements.
In a method for manufacturing a magneto-optical disk having a magnetic recording film made of an alloy containing 10 atomic % or less of at least one element selected from the group of r, Ni, Pt, Rh, and Pd,
Si_3N_4, SiO, SiO_2, T provided between arbitrary layers of various thin film layers constituting the magneto-optical disk.
A magneto-optical disk characterized in that a dielectric film made of at least one of iO_2 and TiN is formed by a laser-excited chemical vapor deposition method using a high-energy laser beam in conjunction with the excitation energy of a source gas. manufacturing method. 9. In forming the dielectric film, SiH_4 and NH_3 were used to form the Si_3N_4 film, and Si was used to form the SiO film.
H_4 and H_2 and O_2 or N_2O, Si
To form the O_2 film, SiH_4 and O_2 were used, and TiO_2
TiCl_4 and H_2O are used as source gases to form the film, and TiCl_4 and NH_3 are used as source gases to form the TiN film, and the film is formed by laser-excited chemical vapor deposition at a substrate temperature of 90°C or less. A method for manufacturing a magneto-optical disk according to claim 8.