JPS62114137A - Production of sputtering target for optical recording - Google Patents

Abstract

PURPOSE:To stabilize sputtering conditions with a uniform compsn. having a high density and to improve productivity by mixing selenium, etc. with tellurium, bringing the same into reaction by heating in a vacuum or inert gaseous atmosphere, and subjecting the mixture to pulverizing in a nor oxidative atmosphere then to molding under pressurization. CONSTITUTION:The sputtering target for optical recording is obtd. by mixing >=1 kinds of metals such as selenium, titanium and silver with a tellurium ally, bringing the mixture into reaction by heating in he vacuum or inert gaseous atmosphere to form telluride and subjecting the mixture to pulverizing and mixing in the nonoxidative atmosphere then to molding under pressurization followed by cutting and finishing. These material are mixed at ratios of 60-100% tellurium, <=30% selenium and <=20% >=1 kinds of metals such as titanium, silver, arsenic and lead. The uniform compsn. approximately equal to the theoretical density is thus obtd. by pulverizing and mixing. The inter- particle binding power is increased by the improvement of sinterability, by which the sputtering conditions are stabilized. The productivity is improved by the continuous sputtering.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to write-once (DRAW) data such as image files, document files, and code information files.
The present invention relates to a method for producing a target that is a raw material for sputtering an optical recording disk (ead after write).

[Prior Art] The first characteristic of optical disk memory is its large storage capacity. Compared to magnetic disks and VTRs, the recording density per unit area is at least 1
It is as high as 0 times or more. Recently, high-capacity magnetic recording memory is expected to emerge due to the development of perpendicular magnetization films, but with magnetic recording methods, wear and tear due to touch and run between the head and the disk cannot be avoided when reading records.
I am facing a lifespan problem.

On the other hand, in the case of light, although it is limited by the wavelength and the aperture of the lens, it has a high potential because it is possible to form a minute spot with a diameter of about 1 μm or less by using a laser.

The second feature is that recording and playback can be performed without contact. As a result, there is no wear and tear on the disk and hardware, resulting in a longer lifespan and higher reliability.

Among optical disk memories, read-only (ROM: rea)
d only memory) have become widely used as optical video discs and compact discs, and some of the write-once type still image disc files and document files that form the core of this invention have also been put into practical use.

Traditionally, optical disks have been manufactured using vapor deposition methods, sputtering methods using a composite target (a combination of several metals in a mosaic pattern, or one metal on top of another), or a sputtering method using a single metal. Multidimensional sputtering methods using a plurality of configured targets have been used.

This is due to the consideration of film composition and the fact that a single metal can provide a higher purity target than conventional alloy targets, but on the other hand, the complexity of the equipment configuration and the difficulty of continuously controlling the film composition Therefore, there were drawbacks such as difficulty in continuous production, low productivity, and high cost.

[Problems to be solved by the invention] The present invention enables sputtering that enables continuous control of the film composition, which was difficult with the conventional techniques as described above, and enables a large-scale, high-productivity film with a uniform composition. The present invention provides a method for manufacturing an alloy target that can be measured.

[Means for Solving the Problems] The present invention involves mixing one or more metals selected from the group consisting of selenium, titanium, silver, arsenic, lead, antimony, and indium with tellurium or a tellurium alloy, and mixing the mixture with tellurium or a tellurium alloy under vacuum. Alternatively, a heating reaction is performed under an inert gas atmosphere such as argon, nitrogen, helium, etc. to form telluride, which is then pulverized and mixed under a non-oxidizing atmosphere, for example in an organic solvent, and the resulting fine powder mixture is directly hot-pressed; Cold isostatic press (
CI P) to form a green compact, further hot press,
The present invention provides a method for manufacturing a sputtering target for optical recording, which is characterized by forming a molded body having a substantially uniform composition and approximately the same theoretical density.

In the present invention, the mixing ratio of each element is generally 60 at% or more but less than 100 at% for tellurium and 0 to 30 at% for selenium.
t%, other titanium, silver, arsenic, lead.

One or more metals selected from the group consisting of antimony and indium are used in an amount of θ to 20 at %.

Next, a method for manufacturing a target according to the present invention will be explained.

First, tellurium or a tellurium alloy is added to one or more metals selected from the group consisting of selenium, titanium, silver, arsenic, lead, antimony, and indium.
Under an inert gas atmosphere such as nitrogen or helium, approximately 350 to 1
The heating reaction is carried out at 100°C. This is then cooled to obtain telluride. Here, as a cooling method after the heating reaction, rapid cooling is preferable. This is because it is thought that amorphous or fine crystals have a better effect on sputtering. The obtained telluride is finely pulverized and mixed in a non-oxidizing atmosphere, for example, an organic solvent, and the obtained fine powder mixture (average particle size: 1 to 100 μm - preferably 2 to 20
μm) thoroughly mixed with a kneader, and then cold isostatically pressed (
CI P) from 1 to 5 tons/d, preferably from 3 to 5 tons
After pressurizing on/c- to obtain a green compact, it is made into an ingot for hot pressing of a predetermined size. When hot pressing the powder, the powder is dried and mixed uniformly to form the raw material. The particle size of the raw material powder such as tellurium powder used here is 2
00 μm or less is generally used.

This is heated using a hot press at 300 to 450°C, preferably 300 to 400°C, in an inert gas atmosphere at 10 kg/kg.
A molded article is obtained by heating and pressing at a pressure of c- or more, preferably 75 to 200 kg/c-.

This molded body is cut and finished using a cutting machine such as a wire electric discharge machine or a band saw to obtain a sputtering target for optical recording in a predetermined shape.

[Effects of the Invention] The target thus obtained has a substantially uniform composition and has approximately the same theoretical density. Furthermore, the sinterability is improved and the bonding force between particles is increased.

The optical recording target obtained according to the present invention is formed into a film by sputtering to form an optical disc.

In this case, a conventional composite target (mosaic-like).

It has the following advantages compared to an optical disk obtained by forming a film from a target consisting of a single metal and chips of other metals. (1) A film having the same composition as the target is obtained and the sputtering conditions are stabilized.

(2) Continuous sputtering becomes possible, improving productivity and reducing costs.

[Examples] The present invention will be explained below using examples. The present invention is not equally limited by these examples.

Example 1 In order to obtain a 30 kg ingot in a high frequency induction melting furnace, T
e 85.38vt%, Se 14. 62v
Argon gas 600 to 11 g at a rate of t%, 450 to 5
The molten metal was melted at 00° C. and cast into a carbon mold under an argon gas atmosphere, and the resulting ingot was crushed using a crusher to obtain alloy powder with an average particle size of 200 μm.

On the other hand, Te 84.2wt%, Ti 15.8vt
% in a quartz sealed tube at 900 to 1000° C. for 5 hours, and the resulting product was pulverized in an argon atmosphere to obtain 1 kg of telluride powder with an average particle size of 100 μm.

Both telluride powders obtained in this way were Te-3e68.4
vt%, Te-Ti 31.6vt%, were pulverized and mixed in cyclohexane for 60 minutes using a ball mill, thoroughly dried, and a raw material powder for hot pressing (Te-Ti 85
．． Se 10. Ti 5 (at%)) was obtained. This was filled into a graphite mold with a diameter of 152.4+uφ and a height of 50+m, and heated in an argon atmosphere at 400°C at 200°C.
Heated and pressurized at kg/c- to form a molded body (H.

P, molded body) was obtained.

This molded body was cut using a wire electrical discharge machine, and 15
A target with a diameter of 2.4 mm and a diameter of 5 ml was manufactured. As shown in Table 1, the target thus obtained had a density close to the theoretical density.

Example 2 Regarding Te-8e, Te-8e was prepared under the same conditions as Example 1.
78. lvt% and Se at a ratio of 21.9wt%.

On the other hand, Te was 81.6 wt% and Ti was 9.2 wt%.

900 to 100 Pb in a quartz sealed tube at a ratio of 9.2 Vt%
The reaction was heated at 0°C for 5 hours, and the resulting product was ground in an argon atmosphere to obtain telluride powder with an average particle size of 100 μm.
I got 2 kg. Both telluride powders obtained in this way were
e-8e 45.7wt%.

Te-Ti-Pb was pulverized and mixed for 60 minutes in cyclohexane using a ball mill at a ratio of 54.3 wt%,
Thoroughly dry, hot press raw material powder (Te 80
．． Se 10. Tl 5. Pb5(at
%)) was obtained.

The obtained powder was packed into a rubber mold and cold isostatically pressed (CI).
Pressure molding was performed using P) at 5 tons/c-. Then, the obtained green compact was heated to 21 G+a×210×
After being processed to a size of 20-■t and sufficiently dried, it was heated and pressed using a hot press at 420° C. and 150 kg/c- in an argon atmosphere to obtain molded bodies (H, P, molded bodies).

This molded body was cut using a wire electrical discharge machine, and
A target of 01 knowledge x 210m x 5IIIt was manufactured. As shown in Table 1, the target thus obtained had a density close to the theoretical density.

Table-1 Density of hot press molded body [Unit: g/a/1]

Claims (1)

[Claims] 1) One or more metals selected from the group consisting of selenium, titanium, silver, arsenic, lead, antimony, and indium are mixed with tellurium or a tellurium alloy, and the mixture is heated under vacuum or with argon, nitrogen, or helium. A heating reaction is carried out under an inert gas atmosphere such as to form telluride, which is then finely pulverized under a non-oxidizing atmosphere.
The obtained fine powder is directly hot-pressed or cold isostatically pressed (CIP) to form a green compact, which is further hot-pressed to form a molded body with a substantially uniform composition and approximately the same theoretical density. A method for producing a sputtering target for optical recording, characterized by: 2) The manufacturing method according to claim (1), in which several types of telluride are pulverized and mixed in a non-oxidizing atmosphere. 3) Telluride in an organic solvent with an average particle size of 0.5 to 50
The manufacturing method according to claim (1) or (2), wherein the manufacturing method is pulverized and mixed to a particle size of μm.