JPH0372153B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to one or more of tellurium, selenium, and antimony used when forming a thin film layer containing one or more of tellurium, selenium, and antimony by a sputtering method. The present invention relates to a method for producing a sintered alloy target material comprising at least one species. [Prior Art] As is well known, one or more of tellurium, selenium and antimony, and/or alloys containing one or more of these, are suitable materials for the recording medium thin film layer of optical disks. In practical use, the thin film layer is generally manufactured by a sputtering method. The target used in this sputtering method is a circular or square plate-shaped target material (hereinafter referred to as target material) such as one or more of tellurium, selenium, and antimony, and/or an alloy containing one or more of these.
It consists of a packing plate (cooling plate) that is soldered to it. Conventionally, such target materials have been produced by melt casting or powder sintering. [Problems to be solved by the invention] However, the composition of these target materials containing one or more of tellurium, selenium, and antimony is Te, Se, Sb, Te-
Se, Te−Pb, Te−Ge, Te−Se−Cd, Te−Se
−Sb−Ag, Se−Sb, Se−Sn, Se−Sn−In, Se
-Te-Sb, etc., but all of them are extremely brittle, have no malleability, and cannot be subjected to plastic working. Therefore, in the melt casting method, not only is the ingot easily cracked and the product yield is poor, but the crystal grains of the ingot are large and gas entrainment occurs during solidification, resulting in gas holes. If sputtering is carried out, abnormal discharge always occurs during sputtering, making it impossible to form a stable thin film. Furthermore, since alloys are prone to segregation, it is not possible to maintain a uniform composition in a thin film. On the other hand, the sintering method involves pulverizing tellurium, selenium, and antimony alone or an alloyed ingot containing one or more of tellurium, selenium, and antimony;
It is press-formed and sintered. The target material made by this method does not have the various disadvantages of the target material made by the above-mentioned melting and casting method, but when sputtering is performed, the target material has poor heat conduction and cannot absorb the generated heat sufficiently. Since it cannot be removed, the temperature rises and the output cannot be increased to a high level. As a result of intensive research aimed at solving the above drawbacks, the present inventors found that the density of the target material made by the sintering method was 80 to 84% of the density of the single substance or its alloy. slightly higher to 85%
It has been found that by doing the above, the thermal conductivity can be significantly improved. In addition, by limiting the particle size of the powder raw material during pressure molding to 100 to 625 mesh, we obtained a new finding that a sintered density of 85% or more, which was difficult to achieve in the past, could be obtained. In addition, in the past, a powder of about 100 mesh or less was generally used as the raw material powder, and no lower limit of the particle size was set. Therefore, the raw material contains 625
A large amount of powder finer than a mesh was contained, and when the particle size distribution was wide, a considerable amount of particles larger than 100 mesh were also mixed in. Since the above-mentioned fine powder has an extremely large surface area per unit weight, a large proportion of the oxidized layer naturally forms on the particle surface, which reduces the adhesion density between the particles and ultimately makes it impossible to obtain a high density. considered to be a thing. Also,
If many particles larger than 100 mesh are mixed in,
It is presumed that the gaps between particles become large, making it impossible to obtain a high sintered density. The present invention was completed based on the above findings, and it is possible to efficiently perform sputtering at high power, and to create an alloy thin film containing one or more of tellurium, selenium, and antimony that is homogeneous, smooth, and excellent. The object of the present invention is to provide a method for manufacturing the target material obtained. [Means for Solving the Problems] The present invention has been made to achieve the above-mentioned object, and the means thereof include the use of tellurium, selenium and antimony alone or any one or more of tellurium, selenium and antimony. By crushing the ingot of the alloy containing the alloy into a homogeneous powder with a particle size of 100 to 625 mesh, press-forming it under high cold isostatic pressure and firing it, the density can be reduced to that of the single substance or the alloy. This is a method for producing a target material with a concentration of 85% or more. The present invention will be further explained in detail. The alloy used as a raw material for the target material according to the present invention is an alloy containing 10 atomic percent or more of any one of tellurium, selenium, and antimony. This alloy or tellurium, selenium, or antimony alone is ground, the particle size is adjusted by sieving, etc., and mixed to obtain a fine, entirely homogeneous powder with a crystal size of 100 to 625 mesh. If the particle size distribution of this powder is too wide, it will become non-uniform, and if the particle size is too large or too small, the strength of the compact will not increase, and cracks will occur during processing or sputtering, causing abnormal electrical discharge during sputtering. Furthermore, the density of the target material does not increase. The powder is then typically held under vacuum to degas it. As conditions for vacuum degassing, the temperature is selected from a range of 30° C. or higher to a temperature at which the vapor pressure of the powder itself is 1 Torr or less, the degree of vacuum is 1 Torr or less, and the treatment is carried out for about 1 to 5 hours. In some cases, this vacuum degassing treatment may be applied to the target material before sputtering. This powder is press-molded using high cold isostatic pressure, and then sintered to create a sintered body with a density of 85% or more of the density of the single substance or alloy itself, which is then machined to cut out the target material. , solder it to the packing plate and use it as a target. Since the target thus obtained has good thermal conductivity and is sufficiently cooled, sputtering can be performed with high output. [Function] According to the method for producing a target material according to the present invention, a target material having a density of 85% or more of the density of a single substance or an alloy thereof can be obtained, and a target made using this target material has a good performance. It is cooled and the temperature does not rise even when high output is applied.
It becomes possible to perform efficient sputtering. The present invention will be explained in more detail by showing Examples and Comparative Examples below. [Examples 1 to 14] Grinding a single substance or alloy with a ball mill,
The powder was sieved to a powder size of 100 to 625 mesh, and vacuum degassed under the conditions shown in the table. This was pressure-formed by cold isostatic pressing and sintered to form a single body or a sintered body having a density of 85% or more of the alloy mass density.
This sintered body is machined to a diameter of 150 mm and a thickness of 6 mm.
The target material was mm. A steel plate was brazed to this target material as a packing plate to serve as a target, and sputtering was performed by cooling with water at a predetermined temperature and flow rate. [Comparative Examples 1 to 14] Same as the examples except that the raw material powder used was one with a particle size distribution wider than 100 to 625 meshes, and the density of the sintered body was less than 85% of the density of the single substance or alloy ingot. Sputtering was performed in the same manner. Table 1 shows the results of Examples and Comparative Examples. In addition, using the results in Table 1, we calculated the improvement rate (%) of sintered density for the same No. of the example and comparative example.
and the improvement rate (%) of thermal conductivity were calculated. The results are shown in Table 2. The calculation method was (Example numerical value - Comparative example numerical value)/Comparative example numerical value x 100.

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〔Effect of the invention〕

As described above, in the method for producing a sintered alloy target material of the present invention, the particle size of the raw material powder is set to 100 to 625.
By limiting the method to mesh and increasing its sintered density to 85% or more, it is possible to produce a target material with significantly improved thermal conductivity. With this target material, sufficient cooling is performed, so the temperature of the target surface does not rise, making it possible to perform sputtering with high output, resulting in a faster formation of a thin film, compared to targets made by conventional sintering methods. It is possible to perform sputtering with extremely high efficiency compared to other materials.

[Brief explanation of drawings]

FIG. 1 is a graph showing the effects of the present invention.

Claims (1)

[Claims] 1 Production of a sintered alloy target material by press-forming powder of one or more of tellurium, selenium, and antimony and/or alloy powder containing one or more of these using cold isostatic pressure and sintering. In the method, the particle size of the powder is 100-625
A method for producing a sintered alloy target material, which is limited to a mesh, has a uniform composition overall, and has a sintered density of 85% or more.