JPH0790566A - Target for alloy sputtering and its production - Google Patents

Abstract

PURPOSE:To film-form a metallic reflection layer or the like for an optical magnetic recording medium having recording sensitivity by including grains containing fine particles having a specific average particle diameter in a specific mirror-finished Al alloy observed with scanning electron microscope. CONSTITUTION:A target for Al alloy sputtering is formed from an Al-M alloy, where M is one or more kinds of Mg, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Cu and Zn. The mirror-finished alloy contains M-enriched fine grains having <=5mum average particle diameter in the observation with the scanning electron microscope. The content of M is 1-40wt.%. The Al-M alloy is melted and made powdery by high speed quenching method and the obtained powder is press molded. As a result, the target for Al-M alloy sputtering uniform in M content is produced even at the time of making the M content high.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an Al alloy sputtering target used for manufacturing a metal thin film and a method for manufacturing the same.

[0002]

2. Description of the Related Art Although various optical recording media have been put to practical use,
Among them, the magneto-optical recording medium is considered promising because of its large information capacity, and its development has been remarkable in recent years. The magneto-optical recording medium is configured by providing a recording layer magnetic film on a transparent substrate via a dielectric layer. Then, recently, a second dielectric layer is provided on the recording layer, the recording layer is sandwiched by a pair of dielectric layers, and a metal reflection layer is provided on the uppermost layer to enhance the output of a reproduction signal.

As such a metal reflection layer, Al or Al alloy is considered promising in terms of light reflectance and cost. Among them, according to Japanese Examined Patent Publication No. 5-24571, an Al-Ni alloy is said to be particularly excellent in order to prevent clouding that occurs in a reflective layer of Al alone. In Japanese Patent Laid-Open No. 61-194664, Al-N
Among the i alloys, those containing 2 to 10 at% Ni are said to be excellent in terms of recording sensitivity and reproduction C / N. A sputtering method is generally used for forming such a metal reflective layer because of its ease of manufacture.

In such a metal reflective layer, the recording sensitivity can be further increased by lowering the thermal conductivity thereof. Therefore, in order to reduce the thermal conductivity of the Al alloy, it is desirable to use a sputtering target with an increased Ni content and form a metal reflective layer with a reduced thermal conductivity.

However, for example, A with an increased Ni content
The l-Ni alloy sputter target does not have uniform film quality when manufactured by a conventional extrusion molding method.
The Ni-rich phase segregates on the target surface. Then, the distribution of Ni content in the metal reflective layer formed by using such an Al-Ni alloy sputtering target is likely to be non-uniform, and variations in the characteristics as the metal reflective layer occur, resulting in desired characteristics. Can't get

In addition to such an Al--Ni alloy, Al
Mg, Ti, Zr, Hf, V, Nb, Ta, Cr, M
The same phenomenon occurs when targeting o, W, Mn, Fe, Co, Cu, Zn and the like and their alloys.

[0007]

The object of the present invention is to provide a uniform alloy composition in a film when used for forming a metal reflective layer of a magneto-optical recording medium, etc. Optical recording such as a magneto-optical recording medium having a higher recording sensitivity, which has less variation and can increase the content rate of alloy constituents and can reduce the thermal conductivity of the metal reflection layer and the like. An object of the present invention is to provide a target for Al alloy sputtering that can obtain a medium and a method for manufacturing the same.

[0008]

These objects are achieved by the present invention described in (1) to (14) below. (1) Al-M alloy (where M is Mg, Ti, Zr,
Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe,
One or more of Co, Ni, Cu and Zn)
A target for sputtered Al alloy having a grain containing the M-rich fine particles having an average particle diameter of 5 μm or less when observed by a scanning electron microscope after being mirror-finished. (2) The above (1), wherein the content of M is 1 to 40 wt%.
Al alloy sputter target. (3) The target for Al alloy sputtering according to (1) or (2) above, wherein M is Ni and is formed from an Al—Ni alloy having a Ni content of 2 to 40 wt%. (4) The target for Al alloy sputtering according to any one of (1) to (3), wherein the grains have an average diameter of 1 μm to 1 mm. (5) The fine particles have an area ratio of 5 to 8 in the grains.
The target for Al alloy sputtering according to any one of the above (1) to (4), which is present at 0%. (6) The target for Al alloy sputtering according to any one of the above (1) to (5), which has a boundary layer around the grain and has M-rich second fine particles in the boundary layer. (7) The average particle size of the second fine particles is 0.1 to 10 μm
The target for Al alloy sputtering according to (6) above. (8) A of the above (6) or (7), wherein the second fine particles are present in the boundary layer in an area ratio of 5 to 80%.
l Alloy sputter target. (9) The above (1) to which the Al-M alloy powder is pressure-molded.
The target for Al alloy sputtering according to any one of (8). (10) The above (1) used for forming a reflective film of an optical recording medium
A target for Al alloy sputtering according to any one of to (8). (11) The Al-M alloy is melted into a powder by a rapid quenching method, and the obtained Al-M alloy powder is pressure-molded A
1. Method for manufacturing target for alloy sputter. (12) The method for manufacturing an Al alloy sputtering target according to the above (11), wherein the pressure forming is performed at a temperature lower than the melting point of Al. (13) The M-rich fine particles are further added to the fine powder obtained by the high-speed rapid cooling method, and the mixture is pressure-molded.
The method for producing a target for Al alloy sputtering according to 1) or (12). (14) The method for manufacturing an Al alloy sputtering target according to any of (11) to (13), wherein M-rich fine particles are present in the Al-M alloy powder.

[0009]

ACTION AND EFFECT The sputtering target of the present invention is
Al-M alloy (M is Mg, Ti, Zr, Hf,
V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co,
It is one or more of Ni, Cu and Zn). Then, preferably, the Al-M alloy is melted into a powder by a rapid quenching method, and the obtained powder is preferably Al.
It is obtained by pressure molding at a temperature lower than the melting point of, and has grains containing M-rich fine particles having an average particle diameter of 5 μm or less. In this case, the fine particles are mainly composed of an intermetallic compound having M excess over the total M content, and the total M content is preferably 1 to 40 wt%. This target has a more uniform M composition than the target for Al-M alloy sputtering produced by the conventional extrusion molding method. That is, for example, when Ni is used as M, the sputter surface of an Al-Ni alloy sputter target having a diameter of 5 inches (about 127 mm) is 1/1 / the diameter in the vertical and horizontal directions.
When the average content of Ni in the obtained 32 sections was measured at equal intervals with a length of 6, the Ni-rich phase fine particles were relatively evenly distributed in the target by the extrusion molding method. Since the particles are oriented in the direction, the average content of Ni in each section changes, and the variation in the average content in each section remarkably varies when the Ni content as a whole is increased. That is, in the extrusion molding method, when the Ni content is, for example, more than 6 wt%, the Ni-rich phase is segregated and unevenly distributed in a striped pattern in the extrusion direction, and it is impossible to produce a target having the same average content in each section. Can not. On the other hand, in the Al-Ni alloy sputtering target of the present invention, Ni
Although the rich fine particles are unevenly distributed in the grain or in the boundary layer in the vicinity of the grain in addition to this, the average content of Ni in the compartments is almost the same between compartments even if the Ni content is large. is there.

That is, according to the present invention, it is possible to manufacture an Al-M alloy sputtering target having a uniform M content even when the M content is higher. Therefore,
By using the target for Al-M alloy sputtering of the present invention, the M content is increased, the thermal conductivity is low, and the metal reflective layer for magneto-optical recording medium or the like having higher recording sensitivity is formed. Is possible.

In a magneto-optical recording medium such as a mini disk, the block error rate (BLER) is particularly 3.
For the recording power lower limit value (Pmin) of 0 × 10 ^-2 or less, the optimum recording power (P ₀ ) expressed as Pmin × 1.4, that is, the optimum power of the recording / writing light for recording on the magneto-optical recording medium. However, the lower the value, the higher the recording sensitivity. For example, when Ni is used as M, this P ₀ decreases as the Ni content of the Al-Ni alloy metal reflection layer increases and decreases as the metal reflection layer thickness decreases, if the metal reflection layer thickness is the same. To do. At this time, the higher the Ni content, the smaller the change in P ₀ with respect to the change in the thickness of the metal reflection layer. That is, when the metal reflective layer is manufactured, P ₀ does not increase even if the film thickness is increased, the film thickness control margin in manufacturing is widened, and the film thickness is unavoidably reduced, resulting in deterioration of reflectivity. In addition, the deterioration of corrosion resistance under high temperature and high humidity is eliminated, which is a great advantage in manufacturing.

Furthermore, using a target for Al alloy sputtering produced by the present invention or the extrusion molding method, the substrate is fixed directly on the target and sputtering is performed, and the M content of the obtained metal layer in the radial direction from the center of the target. When the target by the extrusion molding method was used, the M content in the metal layer was low in the vicinity of the center of the target, and the M content increased as the measurement position moved in the radial direction. Increase. However, when the target of the present invention is used, a thin film having a content substantially equal to the M content of the target can be stably obtained in the vicinity of the center of the target, and the radial change in the M content in the metal layer is marked. And small.

That is, by using the Al-M alloy sputtering target of the present invention, M in the metal reflection layer due to the difference in the radial position from the center of the target during sputtering.
The change in the content is small, and a special effect that the M content in the thin film near the target is almost equal to the target composition is also obtained. Such an effect is an effect first obtained by the target of the present invention.

[0014]

Specific Structure The specific structure of the present invention will be described in detail below.

The Al alloy sputtering target of the present invention is an Al-M alloy (where M is Mg, Ti, Zr or H).
f, V, Nb, Ta, Cr, Mo, W, Mn, Fe, C
O, Ni, Cu and Zn) and has grains containing the M-rich fine particles having an average particle size of 5 μm or less, more preferably 0.01 to 2 μm. And, preferably, the content of M is 1 to
It is 40 wt%. If the M content is too low, the effect of the present invention is reduced, and when a metal reflective layer is formed, for example, the thermal conductivity of the metal reflective layer tends to be high, and the recording sensitivity of the medium tends to be low. Further, if the amount is too large, the effect of the present invention is reduced, and for example, the amorphous state of the metal reflection layer cannot be maintained, the reflectance as the metal reflection layer is likely to be lowered, and the C / N ratio of the medium is also deteriorated. come.

Next, an example will be described in which the most preferable Ni is used as M of the Al-M alloy sputtering target of the present invention, and in particular, a metal reflective layer of a magneto-optical recording medium such as a mini disk is formed. Incidentally, even in the case of M other than Ni,
The microstructure and the like are similar to the following.

When Ni is used as M of the Al-M alloy sputtering target of the present invention, the Ni content is 2 to 4.
0 wt%, more preferably 3 to 20 wt%, especially 6 to 10 wt%
% Is preferable. If the Ni content is too low,
For example, when a metal reflective layer is formed, as described above, the thermal conductivity of the metal reflective layer tends to be high, and the recording sensitivity tends to be low. On the other hand, if the amount is too large, the metal reflection layer cannot maintain an amorphous state, and the reflectance of the metal reflection layer tends to decrease, resulting in deterioration of the C / N ratio.

The Al-Ni alloy sputtering target of the present invention containing Ni in such a range and manufactured by the method described later has an average particle diameter of 5 μm or less, more preferably 0.0
It has grains containing 1-2 μm Ni-rich fine grains. That is, when the target surface is mirror-polished by polishing on a tin surface plate with, for example, dia powder, and then observed with a scanning electron microscope (SEM), grain boundaries are clearly confirmed. In the present specification, the grain containing Ni-rich fine particles refers to the grain confirmed by such treatment. On the other hand, in the Al-Ni alloy sputter target produced by the extrusion molding method, after the mirror-finishing, the grains may be confirmed only after etching with an aqueous solution of iron chloride, but only with the mirror-finishing. Grain is not confirmed.

The average diameter of the grains is preferably from 1 μm to
It is 1 mm, more preferably 2 to 100 μm. In this case, the average particle diameter and the average diameter are represented by the average of the maximum long sides of about 50 grains under the SEM field of view. The Ni-rich (M-rich) fine particles are present in the grain in a certain amount under the SEM field of view, and the area ratio is preferably 5 to 8 in the grain.
0%, more preferably 15-50%. And
Most of the grains mainly have a spherical or nearly flat shape.

Further, a boundary layer usually exists around such a grain, and N is also contained in this boundary layer.
It has i-rich second fine grains. The second fine particles are mainly present in the vicinity of grains, have an average particle size of 0.1 to 10 μm, more preferably 2 to 5 μm, and have an area ratio of 5 to 80% in the boundary layer, more preferably Is 1
5-60% present. These Ni-rich fine particles in the grains and the second fine particles present in the boundary layer are mainly composed of the intermetallic compound NiAl ₃ , and further,
When the Ni content in the Al-Ni alloy is 25-40 wt%, an alloy such as Ni ₂ Al ₃ or NiAl (intermetallic compound)
May also exist. These are X-ray diffraction (XR
It can be confirmed by D). The thickness of the boundary layer is about 5 to 20 μm, and the area ratio is 0 to 30.
%, Particularly preferably 5 to 20%. However, in the case of performing a pressure molding method described later, particularly in the case of molding without heating, there may be a case where there is almost no boundary layer as described above and only a layer having Ni-rich fine particles in the vicinity of grains exists. . In this case, voids may be present together with Ni-rich fine particles. In addition, such A
It is particularly effective to confirm the Ni-rich fine particles of the l-Ni alloy sputtering target from the composition image by SEM.
Further, the portion excluding such a Ni-rich phase is substantially an aluminum phase, and in addition to these composition components, for example, Si, Fe, Cu, etc. derived from impurities of the raw material in the target composition. May be contained at about 1000 ppm or less, and O, N, etc. may be contained at about 1000 ppm or less.

In the above, the case where Ni is used as the M has been described, but the preferable M content in the Al alloy when using a metal other than Ni, the M-rich fine grains in the grain and the boundary layer. The existence form and the like of the second fine particles present therein are shown below.

When M is Mg, the content of M in Al is 2 to
40 wt% is preferable. Also, as M-rich fine particles, gold
The β phase of the intergeneric compound AlMg segregates. When M is Ti
In this case, the M content in Al is preferably 2 to 40 wt%. Also
M-rich fine particles are mainly TiAl₃ Is the main subject. M is
In the case of Hf, the M content in Al is preferably 1 to 30 wt%
Yes. When M is V, M content in Al is 1 to 20 wt%
preferable. M-rich fine particles are mainly VAl₆ And VA
l_Five Is the main subject. If M is Nb or Ta, in Al
In any case, the M content of is preferably 1 to 30 wt%.
When M is Cr, the M content in Al is preferably 1 to 20 wt%.
Good The M-rich fine particles are mainly CrAl.₇ Subject to
And when the M content is 10 to 20 wt%, Cr₁₂
Al₁₁, CrAl_Four May also exist. M is M
In the case of o, the M content in Al is preferably 1 to 20 wt%
Yes. M-rich fine particles are mainly MoAl₁₂Mainly
It When M is W, the M content in Al is 1 to 20 wt%.
preferable. Also, M-rich fine particles are mainly WAl₁₂Mainly
Becomes When M is Mn, the M content in Al is 1 to 30.
wt% is preferred. M-rich fine particles are mainly MnAl.
₆ And MnAl_Four Is the main subject. When M is Fe, in Al
The M content of is preferably 2 to 40 wt%. Also of M rich
Fine particles are mainly FeAl₃ And Fe₂ Al_Five Is the main subject.
When M is Co, the M content in Al is preferably 1 to 30 wt%.
Good Also, M-rich fine particles are mainly Co ₂ Al₉ The Lord
Body, and when the M content is 20 to 30 wt%, Co
_Four Al₁₃, Co₂ Al_Five May also exist. M
When Cu is Cu, the M content in Al is preferably 1 to 30 wt%.
Good Also, M-rich fine particles are mainly composed of intermetallic compound AlC.
The θ phase of u segregates. When M is Zn, M content in Al
The amount is preferably 1 to 30 wt%. Al-Zn is Zn
Gravity segregation occurs.

Further, in the Al alloy sputtering target of the present invention, M forming the Al alloy may be not only these metals exemplified above, but also two or more kinds of these metals.

In the present invention, the average grain size and the average grain size and abundance ratio of such M-rich fine grains in the grain are
Further, the average particle size and the abundance ratio of the second fine particles in the boundary layer are controlled as described above. The distribution of such M-rich fine particles is microscopically localized at the points existing inside the grain and in the vicinity thereof, but is macroscopically isotropic. Therefore, even if the M content is higher, it is possible to obtain a target for Al alloy sputtering in which the M composition is uniform and the M composition is uniform, unlike the target obtained by the extrusion molding method. Therefore, when it is used as a reflection layer of a medium, the recording sensitivity can be further increased without deterioration of the C / N ratio, and the change in P ₀ with respect to the change in the film thickness of the metal reflection plate is small, which is a factor in manufacturing. It is possible to obtain a metal reflective layer which also has the advantage of a wide margin. Further, as described above, the excellent effect that the M content in the metal reflection layer changes little depending on the position from the center right above the target during sputtering can be obtained. Such an effect can be obtained by using any of the above-mentioned metals as M, but among these M, the highest effect can be obtained by using Ni.

On the other hand, in the alloy produced by the extrusion molding method, such grains, boundary layers, and M-rich fine particles are not localized but almost isotropically distributed. The metal reflection layer obtained by sputtering using the target obtained by the extrusion molding method has a low M content near the center of the target, right above the target. Furthermore, the M content in the radial direction of the metal reflection layer increases as the distance from the center directly above the target increases. Further, as the M content of the target increases, the M-rich fine particles are unevenly distributed in the target in a stripe shape parallel to the extrusion direction, so that the M content of the target is not constant. Therefore, it is difficult for the metal reflection layer formed using such a target to have a uniform M content. That is, since the M content of the target used cannot be increased, the M content of the metal reflective layer cannot be increased, and when this is used as a magneto-optical recording medium, the recording sensitivity cannot be increased.

The target for Al alloy sputtering of the present invention is obtained by melting the Al-M alloy having the M content as described above into a powder by the rapid quenching method and press-molding the obtained fine powder. You can

In the following, Ni is used as M and Al of the present invention is used.
A method for manufacturing the alloy sputtering target will be described.

As a raw material of the alloy, Al is used as a raw material metal.
And Ni, are weighed and mixed so that the Ni content is within the above range, melted at 700 to 1000 ° C. by an arc melting method, a high frequency induction melting furnace method, or the like, and made into a powder by a rapid quenching method. As the high-speed quenching method, any method can be used, and various cooling roll methods, centrifugal quenching methods, atomizing methods and the like can be used, but since spherical or flat powder can be easily obtained,
The gas atomizing method is particularly preferable. As the gas to be used, it is preferable to use N ₂ or Ar, He or another inert gas.

When a metal other than Ni is used as M in the melting, the melting temperature used is 700 to 2
The optimum temperature may be selected from the range of about 000 ° C. depending on the metal used.

As for the size of the powder, the maximum long side is 1 μm to 1 mm on average, more preferably 2 to 100 μm. If it is too large, rapid quenching is difficult and Ni-rich particles are less likely to become fine particles. If it is too small, pressure molding becomes difficult.

The obtained powder is pressure-molded. The method of pressure molding may be any method, and for example, an ordinary pressure molding method, hot pressing method (HP), hot isostatic pressing method (HIP) or the like can be used.

In the pressure molding method using the HP method, for example, the obtained powder is filled in a mold made of graphite or the like and pressure molded. The pressure molding condition is a temperature below the melting point of Al, usually above room temperature, more preferably 400 to 650 ° C., 100 kg / cm ^{2 to} 1000 kg / c.
m ² , 5 seconds to 1 hour.

At this time, cooling after heating is preferably 1
00-500 ° C./hour, more preferably 300-500
Cool at a rate of ° C / hour. If the cooling rate is too slow, for example, the average particle size of Ni-rich fine particles contained in the boundary layer or the like may locally become too large, and if too fast, the productivity may decrease. Furthermore, if the temperature during pressure molding is too high, Al will melt and Ni
Structures with grain and boundary layers containing rich fines tend to disappear.

At this time, as a method for pressure molding, it is also possible to further add Ni-rich fine particles to the powder obtained by the high-speed rapid cooling method, mix them, and then press-mold.
The Ni-rich fine particles added here include, for example, N
N such as iAl ₃ , Ni ₂ Al ₃ , NiAl, Ni ₃ Al
Al alloy (intermetallic compound) or Ni containing i, having an average particle size of 0.1 to 10 μm, more preferably 2 to
It is 5 μm. The pressure molding conditions in this case are the same as those described above, but when pressure is applied at a temperature of about room temperature, it is preferably 1 to 5 t / cm ² , and 1 second to 10 minutes. . When Ni-rich fine particles are added and mixed and pressure-molded, the temperature at the time of pressure-molding may be heated within the above temperature range, or may be not heated, for example, about room temperature. It is preferable to heat the layer or the layer for the purpose of precipitating a Ni-rich phase therein. It should be noted that voids may exist between the grains when the powder is pressed without being heated to the extent that the Ni-rich phase is precipitated in the boundary layer or during the pressure molding.

Although the manufacturing method has been described by taking Ni as an example of M, the same applies to the case of the above-mentioned M metal other than Ni.
In addition, the powder obtained by the high-speed quenching method may further contain M
In the case of pressure-molding after adding and mixing rich fine particles, as the M-rich fine particles to be used, in addition to the Ni-rich fine particles, the M-rich metal used as a raw material for the rapid quenching method is used. It may be an Al alloy or the above M. Specifically, the above-mentioned Al alloy of each M metal, an intermetallic compound, or the like and each M metal can be mentioned.

Further, a plurality of M-rich fine-grained metal species may be used and may not be the same as the M metal species contained in the powder obtained by the rapid quenching method.

The grain of the Al alloy sputter target of the present invention thus obtained may have anisotropy in the direction parallel to the pressure forming direction and in the direction perpendicular to the pressure forming direction. No anisotropy is observed in the fine particles precipitated in the boundary layer.

The Al alloy sputtering target of the present invention is suitable as a sputtering target for forming a metal reflective layer of an optical recording medium such as an optical recording medium.
That is, the magneto-optical recording medium is constituted by providing a recording layer magnetic film of Tb ₂₀ Fe ₇₄ Co ₆ or the like on a transparent substrate with a dielectric layer interposed therebetween. And recently, a second dielectric layer is provided on the magnetic film of the recording layer, the recording layer is sandwiched by a pair of dielectric layers, and a metal reflection layer is provided on the uppermost layer thereof to enhance the output of the reproduction signal. However, it is preferably used when forming such a metal reflective layer.

The thickness of the metal reflective layer of an optical recording medium such as a magneto-optical recording medium formed by using the Al alloy sputtering target of the present invention is preferably about 400-1500A. If the film thickness is too thin, the effect as the metal reflection layer is lost, and the output and C / N are likely to decrease. If it is too thick, the sensitivity tends to decrease.

Although the magneto-optical recording medium has been described above as an example, the Al alloy sputtering target of the present invention is
It can also be used for manufacturing various optical recording media other than this.

[0041]

EXAMPLES The present invention will be described in more detail below by showing specific examples of the present invention.

Example 1 Raw materials Al and Ni were weighed and mixed so that the Ni contents were 6 wt% and 8 wt%, and melted at 700 ° C. A powder having an average particle size of 50 μm was obtained by a gas atomization method using N ₂ gas. This powder was filled in a graphite mold, 640 ° C, 130 kg
/ cm ² , 10 ^-2 Torr pressure molding for 10 minutes, diameter 12
7mm, 5mm thick sample 1 (Ni content 6wt
%) And a pressed body sample 2 (Ni content 8 wt%) were obtained.

The surface of the obtained sample was mirror-finished by the above-mentioned method, and the composition images obtained by a scanning electron microscope (SEM) are shown in FIG. 1 (Ni content 6 wt%) and FIG. 2 (Ni content 8 wt%).
%). As composition images with different magnifications (a)
And (b).

Comparative Example 1 A raw material was melted at 700 ° C. in the same manner as in Example 1 except that the Ni content was 6 wt%, then 450 ° C. and an extrusion ratio of 1/1.
Extrusion molding was performed at 0 to obtain Comparative Sample 1.

The cross section of the obtained sample in the direction parallel to the extrusion direction and the cross section in the direction perpendicular to Example 1
A composition image by SEM was obtained in the same manner as in, and shown in FIG. 3 (parallel to the extrusion direction) and FIG. 4 (perpendicular to the extrusion direction).
Composition images with different magnifications (a) and (b)
It was shown to.

As shown in FIGS. 1 and 2, in the SEM composition image of the target for Al-Ni alloy sputter of the present invention whose surface is mirror-finished by the above-mentioned method, Ni-rich fine particles shown in white are shown. It can be seen that the grains contained are recognized, and further, Ni-rich second fine grains having a large average grain size are present in the boundary layer near the grains. On the other hand, even if the surface is mirror-finished by the above-described method, in Comparative Sample 1, no grains are recognized as shown in FIGS. 3 and 4.

Example 2 Using the pressure-molded body sample 1 obtained in Example 1 as a target, a radius of 150 mm was obtained by high frequency magnetron sputtering.
Sputtering is performed on the glass substrate of
An Al-Ni alloy amorphous thin film (thin film 1) of A was formed. The RF power was 750 w, and the center of the target was made to coincide with the center of the substrate and fixed directly above.

The Ni content of the portion shown in Table 1 was measured in the radial direction from the center of the obtained thin film by inductively coupled plasma emission spectroscopy (ICP). The results obtained are shown in Table 1.

[0049]

[Table 1]

Comparative Example 2 Comparative sample 1 obtained in Comparative Example 1 was used, and this was used in Example 1.
Comparative sample 1 for sputtering having the same size as Using this comparative sample 1 for sputtering, an Al-Ni alloy amorphous thin film was obtained on the substrate in the same manner as in Example 2. The obtained thin film was used as a comparative thin film 1, and the Ni content in the portion shown in Table 1 was measured in the radial direction from the center of the thin film as in Example 2. The results obtained are shown in Table 1.

As is clear from Table 1, N of Comparative Thin Film 1
It can be seen that the i content is low near the center. On the other hand, in the thin film 1, the Ni content near the center is close to the Ni content of the target, and the Ni content changes little in the radial direction from the center.

Example 3 A pressure molded body sample 3 (Ni content 10 wt%) having a diameter of 127 mm and a thickness of 5 mm was obtained in the same manner as in Example 1 except that the Ni content was 10 wt%.

Ten pressure-molded body samples 2 and 10 pressure-molded body samples 3 obtained in the same manner as in Example 1 were used, and 10 Al-Ni alloy amorphous thin films were formed under the same conditions as in Example 2. A film was formed.

N of the center position of the target of each obtained thin film
The i content was measured as in Example 2. Table 2 shows the variation range of the average value of the Ni content.

[0055]

[Table 2]

Comparative Example 3 Comparative sample 2 (Ni was prepared by the extrusion molding method in the same manner as in Comparative example 1 except that the Ni contents were 8 wt% and 10 wt%.
Content 8 wt%) and Comparative Sample 3 (Ni content 10 wt%
%) Was obtained.

Comparative sample 2 and comparative sample 3 were each
Using the sample, an Al-Ni alloy amorphous thin film was formed in the same manner as in Example 3.

The Ni content in the center position directly above the target of each thin film obtained was measured in the same manner as in Example 3. Table 2 shows the variation range of the average value of the Ni content.

Example 4 Raw materials Al and Ni were weighed and mixed so that the Ni content was 6 wt%, and melted at 700 ° C. A powder having an average particle size of 50 μm was obtained by a gas atomization method using N ₂ gas. To this powder was added NiAl ₃ powder having an average particle size of 5 μm in an amount such that the Ni content after pressure molding was 8 wt%, and mixed for 2 hours using a V mixer to obtain the mixed powder. It was filled in a cemented carbide (WC) mold and pressure-molded at room temperature at 4 t / cm ² for 20 seconds in the atmosphere to obtain a target for Al-Ni alloy sputtering having a diameter of 127 mm and a thickness of 5 mm.

In the same manner as in Example 1, a composition image of the obtained target by SEM was obtained, and the average particle size was 5 from the composition image.
It was confirmed that there were grains containing Ni-rich fine grains of μm or less, and that Ni-rich fine grains were distributed around the grains.

When a thin film similar to that of Example 3 was prepared using this target, the variation range of the average value of Ni content was similar to that of Example 3.

Example 5 As the M, Mg, Ti, Zr, Hf, V, Nb, T
a, Cr, Mo, W, Mn, Fe, Co, Cu and Z
Using n, Al and these Ms were weighed and mixed so that each M content was 6 wt%, and melted in the range of 700 to 1500 ° C. according to the type of M. Incidentally, each M was mixed with Al alone. A powder having an average particle size of 50 μm was obtained by a gas atomization method using N ₂ gas. This powder was pressed under the same conditions as in Example 1 to obtain a pressed sample sample having a diameter of 127 mm and a thickness of 5 mm.

Using each of the obtained pressure-molded body samples, in the same manner as in Example 1, the SE of the target obtained was obtained.
A composition image of M was obtained. As a result, grains containing M-rich fine particles each having an average grain size of 5 μm or less were recognized from the composition image, and the M-rich second fine grains having a larger average grain size were found in the boundary layer near the grains. Was confirmed to be distributed.

When a thin film similar to that of Example 3 was prepared using this target, a film having a small variation in M content was obtained, though slightly inferior to Example 3.

Example 6 Polycarbonate was injection molded to have a diameter of 86 mm and a thickness of 1.2.
A substrate sample of mm was obtained. On this substrate, SiNx (x
= 1.1) of the first dielectric layer was deposited by high-frequency magnetron sputtering to a layer thickness of 900A. Next, a recording layer having a composition of Tb ₂₀ Fe ₇₄ Co ₆ was formed on the first dielectric layer to a thickness of 200 A by sputtering.

Further, on this recording layer, La ₂ O ₃ 30
A second dielectric layer having a film thickness of 200 A and containing mol%, 20 mol% SiO ₂ and 50 mol% Si ₃ N ₄ was formed by high frequency magnetron sputtering.

On this second dielectric layer, the Ni content was 6 wt.
%, Ni contents of 8 wt% and Ni contents of 10 wt%, and the Ni contents of 6 wt%, 8 wt% and 10 wt% by high frequency magnetron sputtering,
A metal reflective layer having the following thickness was provided. Ni content 6wt%
And with a target of 8 wt%, the film thickness is 5
00, 600 and 700A. Further, in the case of using a target having a Ni content of 10 wt%, the film thickness is 60
0, 700 and 800A.

A protective coat was formed on the metal reflection layer of each of the nine samples obtained. The protective coat was formed by applying an ultraviolet curable resin containing oligoester acrylate and then ultraviolet curing to a thickness of 5 μm. The optimum recording power (P
₀ ) was measured by the following method. The obtained results are shown in FIG.

<Optimum recording power (P ₀ ) measuring method> The disk was rotated at CLV 1.4 m / s and irradiated with a continuous laser beam of 780 nm to perform magnetic field modulation with an applied magnetic field of 200 Oe.
The FM signal was recorded. The recording power is changed and the jitter of the 3T signal is measured. The power Pmi at which the jitter falls below 40 nsec
The n was measured, and the optimum recording power P ₀ = 1.4 × Pmin was calculated.

As shown in FIG. 5, when the metal reflection layer has the same thickness, P ₀ decreases as the Ni content increases. Also,
When the thickness of the metal reflection layer is increased, P ₀ becomes higher, but Ni
By increasing the content rate, the amount of change in P ₀ with respect to the change in the thickness of the metal reflective layer decreases. That is, when the metal reflective layer is manufactured, the film thickness can be increased by increasing the Ni content in the metal reflective layer, and the film thickness control margin in manufacturing is widened, which is a great advantage in manufacturing.

[Brief description of drawings]

1 (a) and 1 (b) are drawings-substituting photographs showing the structure of particles, showing a scanning electron microscope (SEM) of a target for Al—Ni alloy sputtering (Ni content 6 wt%) of the present invention. It is a composition image of.

2 (a) and 2 (b) are drawings-substituting photographs showing the structure of particles, showing a scanning electron microscope (SEM) of the target for Al—Ni alloy sputtering (Ni content 8 wt%) of the present invention. It is a composition image of.

3 (a) and 3 (b) are drawings-substituting photographs showing the structure of particles, showing a cross section parallel to the extrusion direction of an Al—Ni alloy sputter target (Ni content 6 wt%) of a comparative example. It is a composition image of a scanning electron microscope (SEM). The extrusion direction is the lateral direction in the drawing.

4 (a) and 4 (b) are drawings-substituting photographs showing the structure of particles, showing a cross section perpendicular to the extrusion direction of an Al—Ni alloy sputter target (Ni content 6 wt%) of a comparative example. It is a composition image of a scanning electron microscope (SEM).

FIG. 5 is a graph showing the relationship between the metal reflective layer thickness and P ₀ of a magneto-optical recording disk having a metal reflective layer formed by using the Al—Ni alloy sputtering target of the present invention.

[Procedure amendment]

[Submission date] December 29, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0015

[Correction method] Change

[Correction content]

The Al alloy sputtering target of the present invention is an Al-M alloy (where M is Mg, Ti, Zr or H).
f, V, Nb, Ta, Cr, Mo, W, Mn, Fe, C
O, Ni, Cu, and Zn) and has a grain containing the M-rich fine particles having an average particle size of 5 μm or less, more preferably 0.01 to 2 μm. And, preferably, the content of M is 1 to
It is 40 wt%. If the M content is too low, the effect of the present invention is reduced, and when a metal reflective layer is formed, for example, the thermal conductivity of the metal reflective layer tends to be high, and the recording sensitivity of the medium tends to be low. Further, if the amount is too large, the effect of the present invention is reduced, and, for example, it becomes difficult to maintain a good amorphous state or crystalline state as the metal reflection layer, and thus the reflectance as the metal reflection layer tends to be lowered, and the C of the medium is reduced. /
The N ratio also deteriorates.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction content]

When Ni is used as M of the Al-M alloy sputtering target of the present invention, the Ni content is 2 to 4.
0 wt%, more preferably 3 to 20 wt%, especially 6-1
It is preferably 0 wt%. If the Ni content is too low, for example, when the metal reflective layer is formed, the thermal conductivity of the metal reflective layer tends to be high, and the recording sensitivity tends to be low, as described above. On the other hand, if the amount is too large, the reflectance of the metal reflective layer tends to decrease, and the C / N ratio tends to deteriorate.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

When M is Mg, the content of M in Al is 2 to
40 wt% is preferable. Further, as M-rich fine particles, the β phase of the intermetallic compound AlMg segregates. When M is Ti, the M content in Al is preferably 2 to 40 wt%. Further, the M-rich fine particles are mainly composed of TiAl ₃ . M
When Zr is Zr, the M content in Al is preferably 1 to 30 wt%. Further, the M-rich fine particles are mainly composed of ZrAl ₃ . When M is Hf, the M content in Al is 1 to 3
0 wt% is preferable. When M is V, the M content in Al is preferably 1 to 20 wt%. The M-rich fine particles are mainly composed of VAl ₆ and VAl ₅ . When M is Nb or Ta, the M content in Al is 1 to 3 in all cases.
0 wt% is preferable. When M is Cr, the M content in Al is preferably 1 to 20 wt%. The M-rich fine particles are mainly composed of CrAl ₇ , and the M content is 10 to 10.
In the case of 20 wt%, it may exist as Cr ₁₂ Al ₁₁ and CrAl ₄ . When M is Mo, the M content in Al is preferably 1 to 20 wt%. The M-rich fine particles are mainly composed of MoAl ₁₂ . When M is W, A
The M content in 1 is preferably 1 to 20 wt%. Further, M-rich fine particles are mainly composed of WAl ₁₂ . M is Mn
In this case, the M content in Al is preferably 1 to 30 wt%. The M-rich fine particles are mainly MnAl ₆ and MnAl.
₄ is the main subject. When M is Fe, the M content in Al is preferably 2 to 40 wt%. In addition, M-rich fine particles are mainly FeAl ₃ and Fe ₂ Al ₅ . When M is Co, the M content in Al is preferably 1 to 30 wt%.
Further, the M-rich fine particles are mainly composed of Co ₂ Al ₉ ,
Further, when the M content is 20 to 30 wt%, Co ₄ Al
₁₃ and Co ₂ Al ₅ may be present. M is C
In the case of u, the M content in Al is preferably 1 to 30 wt%. The M-rich fine particles are mainly composed of the intermetallic compound AlCu.
Θ phase segregates. When M is Zn, the M content in Al is preferably 1 to 30 wt%. Further, Al-Zn causes gravity segregation of Zn.

Claims (14)

[Claims] 1. An Al-M alloy (where M is Mg, T
i, Zr, Hf, V, Nb, Ta, Cr, Mo, W, M
n, Fe, Co, Ni, Cu, and Zn), and is M-rich with an average particle size of 5 μm or less when observed by a scanning electron microscope with mirror surface processing. Target for Al alloy sputtering having grains containing fine particles of 2. The Al alloy sputtering target according to claim 1, wherein the content of M is 1 to 40 wt%. 3. The M is Ni, and the Ni content is 2 to 4.
The Al alloy sputtering target according to claim 1 or 2, which is formed of 0 wt% Al-Ni alloy. 4. The target for Al alloy sputtering according to claim 1, wherein the average diameter of the grains is 1 μm to 1 mm. 5. The target for Al alloy sputtering according to claim 1, wherein the fine grains are present in the grains in an area ratio of 5 to 80%. 6. The target for Al alloy sputtering according to claim 1, wherein a boundary layer is provided around the grain, and M-rich second fine particles are contained in the boundary layer. 7. The average particle size of the second fine particles is 0.1 to 10.
The Al alloy sputtering target according to claim 6, which has a thickness of 10 μm. 8. The target for Al alloy sputtering according to claim 6, wherein the second fine particles are present in the boundary layer in an area ratio of 5 to 80%. 9. The target for Al alloy sputtering according to claim 1, wherein Al-M alloy powder is pressure-molded. 10. The target for Al alloy sputtering according to claim 1, which is used for forming a reflective film of an optical recording medium. 11. A method for producing a target for Al alloy sputtering, in which an Al-M alloy is melted and made into powder by a rapid quenching method, and the obtained powder of Al-M alloy is pressure-molded. 12. The method for manufacturing an Al alloy sputtering target according to claim 11, wherein the pressure forming is performed at a temperature lower than a melting point of Al. 13. The method for producing an Al alloy sputtering target according to claim 11, wherein M-rich fine particles are further added to the fine powder obtained by the rapid quenching method and the mixture is pressure-molded. 14. The Al according to claim 11, wherein M-rich fine particles are present in the Al-M alloy powder.
Method for manufacturing target for alloy sputter.