JPH11279752A - Production of sputtering target for phase transition-type optical recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the method for producing a sputtering target for a phase transition type optical recording medium being a hardly sinterable material so as to regulate the structure with high mass-productivity. SOLUTION: In this method for producing the sputtering target for phase transition type optical recording having a compsn. contg. at least one kind among Ge, Ag and In by 3 to 50 atomic % and 10 to 50 atomic % Sb, contg., at need, <5 atomic % additive, and the balance substantial Te, as the raw material powder, alloy powder contg. at least one kind among Ge, Ag and In, a prescribed amt. of Sb and a prescribed amt. of Te, preferably atomizing alloy powder stomized from the molten state and rapidly cooled is used and is sintered by a discharge plasma method. The temp. rising to a prescribed temp. at the time of the discharge plasma sintering is executed within 30 min, and the holding to the prescribed temp. is executed within 30 min.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a sputtering target used for manufacturing a phase-change optical recording medium by a sputtering method.

[0002]

2. Description of the Related Art Since a phase change type optical recording sputtering target is a hardly sinterable material, it is usually manufactured by vacuum hot pressing or HIP. However, both methods are expensive in equipment cost and inferior in mass productivity.
It has the drawback of increasing the product cost.
In addition, it is necessary to control the structure of the target in order to prevent abnormal discharge that occurs during film formation and to maintain uniform film thickness distribution and film quality of the formed film. For this reason, there is a problem that sintering conditions are restricted, and it is difficult to obtain a sufficiently high-density sintered body.

[0003]

DISCLOSURE OF THE INVENTION The present invention solves the above problems, is excellent in mass productivity, and can control the organization.
An object of the present invention is to provide a method for manufacturing a target.

[0004]

As a result of various studies, the present inventors have found that the above object can be solved by using a discharge plasma sintering method, and have reached the present invention. In other words, the present invention for solving the above-mentioned problem is that at least one of Ge, Ag, and In is 3 to 50 atomic% and Sb is 10 to 10 atomic%.
In a method for producing a phase change optical recording sputtering target containing 50 atomic%, optionally containing less than 5 atomic% of additives, and the balance being substantially Te, G is used as a raw material powder.
e, Ag, In and at least one of S
b, and an alloy powder obtained by combining a predetermined amount of Te, preferably an atomized alloy powder that has been atomized from a molten state and quenched, and sintered by a discharge plasma method. Is maintained within 30 minutes, and holding at a predetermined temperature is performed within 30 minutes.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS When a film is formed using a sputtering target, it is necessary that the obtained film is homogeneous. Further, it is necessary that abnormal discharge or the like does not occur during film formation. For this purpose, it is desired that the composition of the sputtering target be uniform and not separated into a plurality of phases. Therefore, it is necessary to control the structure of the obtained sputtering target.

This is why the alloy powder is used as the raw material powder in the present invention, and it is desirable to use a powder obtained by quenching from a molten state by a gas atomizing method or the like in order to make it easier to control. Further, in the present invention, the time required to raise the temperature to the predetermined temperature is set to 30 minutes or less, and the holding time at the predetermined temperature is set to 30 minutes or less from the viewpoint of the above-mentioned tissue control. For better organizational control,
It is desirable that the temperature rise to the predetermined temperature be within 20 minutes and the holding time at the predetermined temperature be within 15 minutes.

The particle size of the alloy powder to be used is not particularly limited. However, it is preferable that the average particle size is 10 to 200 μm because a sufficient powder supply density can be obtained and a high-density sintered body can be easily obtained.

Although the density of the sputtering target does not particularly affect the film quality, it is desirable that the density be high in consideration of the life of the target. Therefore, it is preferable to secure a relative density of 90% or more. In the present invention, it is relatively easy to control the sintering temperature by 90%.
The above high-density target can be obtained.

[0009]

Next, the present invention will be further described with reference to examples.

(Example 1) Ge 22 at%, Sb 2
An ingot containing 2 at% and 56 at% Te was pulverized to obtain an alloy powder having an average particle diameter of 100 μm, supplied to a graphite mold having a diameter of 130 mm, and then pressured to 100 kg using a discharge plasma sintering machine. / Cm ² and 15 to 400 ° C
And heated at 400 ° C. for 10 minutes to obtain a sintered body.
After processing this sintered body to 127 mmφ and a thickness of 5 mm, the density was measured and the relative density was 95%.

After the processed sputtering target was bonded to a copper backing plate, DC sputtering was performed on a glass substrate according to a conventional method to obtain a 500 angstrom thick Ge, Sb, and Te alloy film. The obtained film had no problem in film thickness distribution and recording characteristics, and was good.

During the sputtering, an abnormal discharge of about 1 to 2 times / minute was observed.

(Example 2) 22% by atom of Ge and 2% of Sb
Using a melt containing 2 atomic% and 56 atomic% of Te, the average particle diameter was 150 μm by a gas atomizing method using argon gas.
m was prepared and supplied to a graphite mold having a diameter of 130 mm, and the pressure was increased to 100 kg / cm ² using a discharge plasma sintering machine. After holding for 10 minutes, a sintered body was obtained. The density was measured after processing this sintered compact into a diameter of 127 mm and a thickness of 5 mm, and the relative density was 95%.

After joining the processed sputtering target to a copper backing plate, DC sputtering was performed on a glass substrate according to a conventional method to obtain a 500 Å thick Ge, Sb, and Te alloy film. The obtained film had no problem in film thickness distribution and recording characteristics, and was good.

No abnormal discharge was observed during sputtering, and the deposition rate was 5 times between the start of use and the end of use.
%.

Example 3 A sintered body was obtained in the same manner as in Example 2 except that the temperature was raised to 400 ° C. in 30 minutes at the time of sintering and the temperature was maintained at 400 ° C. for 30 minutes to obtain a sintered body. . The density was measured after processing this sintered compact into a diameter of 127 mm and a thickness of 5 mm, and the relative density was 95%.

After the processed sputtering target was bonded to a copper backing plate, DC sputtering was performed on a glass substrate according to a conventional method to obtain a Ge, Sb, and Te alloy film having a thickness of 500 angstroms. The obtained film had no problem in film thickness distribution and recording characteristics, and was good.

Incidentally, an abnormal discharge of about 1 to 2 times / minute was observed during sputtering.

Example 4 The average particle size of the alloy powder used was 5
A sintered body was obtained in the same manner as in Example 1 except that the thickness was set to 0 μm. The density was measured after processing this sintered compact into a diameter of 127 mm and a thickness of 5 mm, and the relative density was 98%.

After the processed sputtering target was bonded to a copper backing plate, DC sputtering was performed on a glass substrate according to a conventional method to obtain a 500 Å thick Ge, Sb, and Te alloy film. The obtained film had no problem in film thickness distribution and recording characteristics, and was good.

Incidentally, an abnormal discharge of about 1 to 2 times / minute was observed during sputtering.

Example 5 The atomized powder obtained in Example 2 was pulverized to produce a powder having an average particle diameter of 10 μm. A sintered body was obtained in the same manner as in Example 1 except that this alloy powder was used. After processing this sintered body to a diameter of 127 mm and a thickness of 5 mm, the density was measured and the relative density was 94%.

After the processed sputtering target was bonded to a copper backing plate, DC sputtering was performed on a glass substrate according to a conventional method to obtain a 500 Å thick Ge, Sb, and Te alloy film. Although the obtained film had no particular problem in the film thickness distribution and the recording characteristics, Example 1 was used.
When compared with, the variation in the film thickness distribution was slightly larger.

It should be noted that the abnormal discharge during sputtering is also 2 to 2.
It increased to about 3 times / minute.

Example 6 The average particle size of the alloy powder used was 2
A sintered body was obtained in the same manner as in Example 1 except that the thickness was set to 00 μm. After processing this sintered body into a diameter of 127 mm and a thickness of 5 mm, the density was measured and the relative density was 91%.

After the processed sputtering target was joined to a copper backing plate, DC sputtering was performed on a glass substrate according to a conventional method to obtain a 500 Å thick Ge, Sb, and Te alloy film. Although the obtained film had no particular problem in the film thickness distribution and the recording characteristics, Example 1 was used.
When compared with, the variation in the film thickness distribution was slightly larger.

Example 7 The atomized powder obtained in Example 2 was pulverized to produce a powder having an average particle size of 8 μm. A sintered body was obtained in the same manner as in Example 1 except that this alloy powder was used. After processing this sintered body into a diameter of 127 mm and a thickness of 5 mm, the density was measured and the relative density was 92%.

After the processed sputtering target was bonded to a copper backing plate, DC sputtering was performed on a glass substrate according to a conventional method to obtain a 500 angstrom thick Ge, Sb, and Te alloy film. The obtained film was usable although it was inferior to Examples 1 and 2 in film thickness distribution and recording characteristics.

The abnormal discharge during sputtering is 7 to
It was about 9 times / minute.

Example 8 The average particle size of the alloy powder used was 2
A sintered body was obtained in the same manner as in Example 1 except that the thickness was 50 μm. After processing this sintered body to a diameter of 127 mm and a thickness of 5 mm, the density was measured and the relative density was 93%.

After the processed sputtering target was bonded to a copper backing plate, DC sputtering was performed on a glass substrate according to a conventional method to obtain a 500 angstrom thick Ge, Sb, and Te alloy film. The obtained film was usable although it was inferior to Examples 1 and 2 in film thickness distribution and recording characteristics.

The abnormal discharge during sputtering is 5 to
It was about 6 times / minute.

Comparative Example 1 A sintered body was obtained in the same manner as in Example 2 except that the temperature was raised to 400 ° C. in 45 minutes during sintering and held at 400 ° C. for 45 minutes to obtain a sintered body. . The density was measured after processing this sintered compact into a diameter of 127 mm and a thickness of 5 mm, and the relative density was 95%.

After the processed sputtering target was bonded to a copper backing plate, DC sputtering was performed on a glass substrate according to a conventional method to obtain a Ge, Sb, and Te alloy film having a thickness of 500 Å. It was found that the obtained film had poor film thickness distribution and recording characteristics and was unsuitable for use.

It should be noted that abnormal discharge during sputtering is also 23
It increased to about 28 times / minute.

When the structure of the sputtering target was analyzed after the completion of the sputtering, a part where two phases were separated was observed.

[0037]

According to the present invention, since the discharge plasma sintering method is used, the rate of temperature rise can be increased, and the production of the target is completed before the structure is separated into two phases. It is possible to get.
Further, the method of the present invention is excellent in mass productivity, so that the economic effect is also large.

Claims (3)

[Claims] 1. A method according to claim 1, wherein at least one of Ge, Ag, and In is contained in an amount of 3 to 50 atomic% and Sb in an amount of 10 to 50 atomic%.
In a method for producing a sputtering target for phase-change optical recording, which contains an additive of less than 5 atomic% as necessary and the balance is substantially Te, at least one of Ge, Ag, and In as raw material powder and a predetermined amount Sb and a predetermined amount of T
e, and sintering is performed by a discharge plasma method using an atomized alloy powder which is atomized from a molten state and rapidly cooled, and the temperature is raised to a predetermined temperature during discharge plasma sintering by 30%. A method for producing a sputtering target for phase-change optical recording, wherein the sputtering is performed within minutes and the holding at a predetermined temperature is performed within 30 minutes. 2. An atomized alloy powder which is atomized from a molten state and quenched as a raw material powder.
The described method. 3. The raw material powder has an average particle size of 10 to 20.
3. The method according to claim 1, wherein a powder of 0 μm is used.