KR20160066239A - Preparation method of tungsten sputtering target and the tungsten sputtering target prepared thereby - Google Patents
Preparation method of tungsten sputtering target and the tungsten sputtering target prepared thereby Download PDFInfo
- Publication number
- KR20160066239A KR20160066239A KR1020140170337A KR20140170337A KR20160066239A KR 20160066239 A KR20160066239 A KR 20160066239A KR 1020140170337 A KR1020140170337 A KR 1020140170337A KR 20140170337 A KR20140170337 A KR 20140170337A KR 20160066239 A KR20160066239 A KR 20160066239A
- Authority
- KR
- South Korea
- Prior art keywords
- sputtering target
- tungsten
- tungsten sputtering
- pressure
- sintering
- Prior art date
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/02—Compacting only
- B22F3/04—Compacting only by applying fluid pressure, e.g. by cold isostatic pressing [CIP]
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/12—Both compacting and sintering
- B22F3/14—Both compacting and sintering simultaneously
- B22F3/15—Hot isostatic pressing
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
- C23C14/34—Sputtering
- C23C14/3407—Cathode assembly for sputtering apparatus, e.g. Target
- C23C14/3414—Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2201/00—Treatment under specific atmosphere
- B22F2201/20—Use of vacuum
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physical Vapour Deposition (AREA)
Abstract
Description
The present invention relates to a method of manufacturing a sputtering target used for semiconductor fabrication and a sputtering target produced by the method.
A sputtering target made of tungsten (hereinafter referred to as a "tungsten sputtering target") is mainly used for forming a gate electrode or a circuit. Such a tungsten sputtering target requires properties such as low resistance, fine grain, and high purity for thermal and chemical stability.
The conventional tungsten sputtering target is manufactured by a method of hot rolling the ingot manufactured by the electron beam melting method, a method of hot-pressing or sintering the tungsten powder, a method of hot-pressing or sintering the tungsten powder, and a hot rolling method.
However, the tungsten sputtering target produced by the above methods has problems such as bonding by particles and coarsening of crystal grains, and it is difficult to form a uniform film due to deformation of the structure after rolling.
Therefore, there is a demand for development of a tungsten sputtering target having fine grains, high density and high purity.
In order to solve the above problems, it is an object of the present invention to provide a method of manufacturing a tungsten sputtering target having fine grains, high density and high purity.
It is another object of the present invention to provide a tungsten sputtering target manufactured by the above-described method.
In order to achieve the above object, the present invention provides a method of manufacturing a molded article, comprising: a) molding a formed article with tungsten powder; b) cold isostatic pressing the formed body; c) subjecting the cold isostatic pressure-press molded article to a vacuum heat treatment; And d) sintering the vacuum heat-treated compacted body by hot isostatic pressing. The present invention also provides a method of manufacturing a tungsten sputtering target.
Here, the pressure for forming the molded body in the step a) may be 20 to 100 MPa.
In addition, the pressure for pressing the molded body in the step b) may be 1,500 to 2,700 bar.
In the step c), the temperature for the heat treatment of the formed body may be 1,700 to 2,000 ° C, and the time for the heat treatment may be 2 to 5 hours.
In addition, the temperature for sintering the formed body in step d) may be 1,700 to 1,900 ° C, the sintering pressure may be 100 to 200 MPa, and the sintering time may be 2 to 5 hours.
The present invention also provides a tungsten sputtering target manufactured by the above manufacturing method.
Since the tungsten sputtering target is manufactured through cold isostatic pressing, vacuum heat treatment, and hot isostatic sintering, the present invention can provide a tungsten sputtering target having fine grain size, high purity and high density.
1 is a flowchart showing a method of manufacturing a tungsten sputtering target of the present invention.
2 is an image showing the crystal grains of the tungsten sputtering target produced in Example 1 of the present invention.
3 is an image showing the crystal grains of the tungsten sputtering target manufactured in Comparative Example 3. FIG.
Hereinafter, the present invention will be described.
The present invention relates to a method of manufacturing a tungsten sputtering target and a tungsten sputtering target manufactured by the method, and will be described with reference to the drawings.
1. Manufacturing method of tungsten sputtering target
a) Molded body manufacture
First, a formed body having a predetermined shape is formed of tungsten (W) powder. At this time, the tungsten powder to be used is not particularly limited as long as it is known in the art, but it is preferably a 5N-grade high-purity tungsten powder having a purity of 99.998 wt% or more. It is also preferable to use a tungsten powder containing not more than 500 ppm of oxygen, not more than 100 ppm of carbon, and less than 50 ppm of nitrogen, hydrogen and sulfur, respectively.
The method of molding the molded article with the tungsten powder is not particularly limited as long as it is a method known in the art, but a molded article can be molded by filling the mold with tungsten powder and pressing the article. At this time, the molding pressure applied to the mold for molding the molded body is not particularly limited, but is preferably 20 to 100 MPa. If the molding pressure is less than 20 MPa, the hardness and density of the molded article become weak. If the molding pressure exceeds 100 MPa, the molded article may be broken due to the springback phenomenon.
On the other hand, the shape of the molded body is not particularly limited, but may be a disc-shaped body, but is not limited thereto. The thickness and the diameter of the molded body may be determined based on the value obtained by inversely reducing the shrinkage ratio of the molded body as the molded body is subjected to cold isostatic pressing and vacuum heat- . In addition to this, it is preferable to use a jig for powder filling so that the tungsten powder in the mold can be dense and filled with an equal height. When the powder filling jig is used, a molded article having a minimized thickness (height) deviation can be obtained.
The molded article of the present invention thus formed has a molding density of 40% or more and is easy to handle, and the tungsten sputtering target to be produced finally becomes a basis for high density.
b) Cold Isostatic Pressing (CIP)
Next, the formed body is subjected to cold isostatic pressing. Specifically, a molded article is put into a plastic container (for example, a rubber container) having a plasticity, or the molded article is vacuum-packed with a wrapping paper (the shrinkage rate of the molded article is controlled by introducing a jig above and below the molded article in vacuum packaging) To apply a uniform pressure to the front surface. The pressure at which the molded article is sealed is not particularly limited, but it is preferably 1,500 to 2,700 bar in consideration of the density of the molded article.
As described above, the cold isostatic pressing causes the molded article having a relative density of 50% or more and having homogeneous isotropy to be obtained.
On the other hand, it is preferable that the relative density of the molded body after completion of the cold isostatic pressing treatment is determined by removing moisture outside the wrapping paper surrounding the molded body, removing the wrapping paper, and measuring the dimensions of the molded body. If the relative density is confirmed by using a hydrometer, moisture may penetrate the molded body, and the degree of vacuum may be lowered during the vacuum heat treatment process.
c) Vacuum heat treatment (no pressure sintering)
Then, the cold-isostatic pressed body is subjected to high-vacuum heat treatment. Here, in order to prevent the incorporation of carbon, it is preferable to place the molded body on a pedestal (plate or setter) made of tungsten and conduct vacuum heat treatment.
On the other hand, the conditions for subjecting the molded article to the vacuum heat treatment are not particularly limited, but the temperature for the heat treatment of the molded article is preferably 1,700 to 2,000 DEG C, and the time for the heat treatment of the molded article is preferably 2 to 5 hours. If the temperature for the heat treatment is less than 1,700 ° C, it is difficult to obtain a molded body having a required relative density or pores may be formed in the molded body, and if it exceeds 2,000 ° C, the size of crystal grains or pores of the molded body may become large.
According to the vacuum heat treatment as described above, the present invention can obtain a molded body (sintered body) having a relative density of 95% or more.
d) Hot Isostatic Pressing (HIP)
Then, the vacuum heat-treated compact is hot-water-sintered. Specifically, the molded article is sintered at a high temperature and a high pressure in the presence of an inert gas (for example, nitrogen, argon, etc.). When the compact is sintered by hot isostatic pressing, the inert gas, which is a pressure medium, maintains the equal pressure so that the shape of the compact does not change during sintering. The pores existing in the compact due to high temperature and high pressure are minimized, have.
The temperature at which the formed body is sintered under hot isostatic pressing is not particularly limited, but is preferably 1,700 to 1,900 ° C. If the sintering temperature is less than 1,700 ° C, it may be difficult to obtain a sintered body having a reduced relative density or a desired density. If the sintering temperature is higher than 1,900 ° C, the crystal grains of the sintered body may become coarsened or the gas content may increase The purity of the sintered body may be lowered.
Also, the pressure and time for sintering the molded body are not particularly limited, but the sintering pressure is preferably 100 to 200 MPa and the sintering time is preferably 2 to 5 hours. The working vacuum degree is preferably 10 -4 to 10 -5 Torr.
According to the present invention, a sintered body having a relative density of 99.3% or more and a crystal grain size of 20 μm or less (specifically, 10 μm or less) and having oxygen and carbon of less than 50 ppm each can be obtained by hot hydrostatic sintering.
The sintered body obtained through the above process may further be subjected to bonding and processing processes known in the art. Specifically, the sintered body is bonded to a backing plate, processed to a required size, and the bead and arc treatment are performed on the backing plate surface. Then, the tungsten sputtering target is manufactured through the cleaning and packaging process.
According to the manufacturing method of the present invention, a tungsten sputtering target having a low content of oxygen and carbon which acts as an impurity can be produced by cold isostatic pressing and vacuum heat treatment, and the crystal grains of the tungsten sputtering target can be easily controlled . In addition, when the manufacturing method of the present invention is applied, the tungsten sputtering target can be mass-produced, and the capacity can be increased about 10 times or more.
2. Tungsten sputtering target
The present invention provides a tungsten sputtering target produced by the above production method. The tungsten sputtering target according to the present invention has a high density of 99.3% or more, a high purity of oxygen and carbon of less than 50 ppm, and a fine grain size of 20 탆 or less.
The field of use of the tungsten sputtering target of the present invention is not particularly limited, but is preferably used for wiring formation or electrode formation in semiconductor production.
Hereinafter, the present invention will be described in detail with reference to Examples. However, the present invention is not limited by the following Examples.
[Example 1]
A 5N grade tungsten powder containing 500 ppm of oxygen and 100 ppm of carbon and having a particle size of 10 μm and a purity of 99.998 wt% was filled in a mold and mounted on a molding press, and a molding density of 40% And then vacuum-packed them.
Next, a molded article having a relative density of 53% was produced by applying a pressure of 2,500 bar to the vacuum packed molded article for 2 hours.
Then, the formed body was heat-treated at 1,800 ° C. for 3 hours in a vacuum atmosphere to obtain a molded body (sintered body) having a relative density of 96%.
Finally, a sintered body having a relative density of 99.4%, that is, a tungsten sputtering target was produced by applying a pressure of 170 MPa at 1,800 DEG C for 2 hours under a working vacuum degree of 10.sup.- 5 Torr.
[Comparative Example 1]
A tungsten sputtering target was prepared by hot pressing (HP) the tungsten powder used in Example 1. At this time, the hot press was performed under the condition of applying a pressure of 20 MPa for 3 hours at 1,900 ° C.
[Comparative Example 2]
The tungsten powder used in Example 1 was subjected to hot isostatic sintering to prepare a tungsten sputtering target. At this time, the hot hydrostatic sintering was performed under the condition of applying 150 MPa pressure at 1,850 ° C for 5 hours.
[Comparative Example 3]
The tungsten powder used in Example 1 was hot pressed and sintered under hot isostatic pressure to prepare a tungsten sputtering target. At this time, the hot press was performed under the condition of applying pressure of 39 MPa for 3 hours at 1,550 ° C, and the hot hydrostatic sintering was performed under the condition of applying pressure of 176 MPa for 3 hours at 1,700 ° C.
[Experimental Example 1] Confirmation of crystal grain of tungsten sputtering target
The sagging of the tungsten sputtering target (sintered body) prepared in each of Example 1 and Comparative Example 3 was confirmed by an optical microscope, and the results are shown in FIG. 2 and FIG. 3, respectively.
Referring to FIGS. 2 and 3, it can be seen that the tungsten sputtering target produced by the method of the present invention has fine grains.
[Experimental Example 2] Evaluation of physical properties of tungsten sputtering target
The physical properties of the tungsten sputtering target prepared in Example 1 and Comparative Examples 1 to 3 were evaluated by the following methods. The results are shown in Table 1 below.
(1) Relative density: Relative density was measured using Archimedes' principle. When the theoretical density 19.3 was applied to obtain a relative density of 99% or more, it was judged to have a high density.
(2) Gas content: Gas content was analyzed by OHN analyzer and CS analyzer. When the content of O was 50 ppm or less and the content of C was 50 ppm or less, it was judged that the gas content was low and high purity.
Referring to Table 1, it can be seen that the tungsten sputtering target manufactured by the manufacturing method of the present invention has high relative density and high purity.
[Experimental Example 3] Evaluation of physical properties of a thin film formed by a tungsten sputtering target
The tungsten sputtering target of Example 1 and Comparative Examples 1 to 3 was indium-bonded to a backing plate for 4 inches, and then applied to a DC magnetron sputtering apparatus (Model: SME-200E) to form a tungsten thin film. Specifically, the substrate used for forming the tungsten thin film was a bare wafer, and the temperature of the substrate was room temperature. The deposition power was 2,200 W, the argon gas was fixed at 75 sccm, and the tungsten film was deposited on the wafer to a thickness of about 500 Å. Then, the sheet resistance and the uniformity were evaluated by the following methods, and the results are shown in Table 2 below.
(1) Surface resistance: Measured by Four Point Probe Resistivity Measurement method using Four Point Probe.
(2) Uniformity: After measuring the thickness of the thin film at any five points, the deviation was calculated.
Referring to Table 2, it was confirmed that the tungsten sputtering target manufactured by the manufacturing method of the present invention can form a thin film having a low sheet resistance and a high uniformity.
Claims (6)
b) cold isostatic pressing the formed body;
c) subjecting the cold isostatic pressure-press molded article to a vacuum heat treatment; And
d) sintering the vacuum heat-treated compacted body by hot isostatic pressing.
Wherein the pressure for forming the formed body in the step (a) is 20 to 100 MPa.
And the pressure for pressing the formed body in the step b) is 1,500 to 2,700 bar.
Wherein the temperature for the heat treatment of the formed body in the step (c) is 1,700 to 2,000 DEG C and the time for the heat treatment is 2 to 5 hours.
Wherein the temperature for sintering the formed body in step (d) is 1,700 to 1,900 ° C, the sintering pressure is 100 to 200 MPa, and the time for sintering is 2 to 5 hours.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020140170337A KR20160066239A (en) | 2014-12-02 | 2014-12-02 | Preparation method of tungsten sputtering target and the tungsten sputtering target prepared thereby |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020140170337A KR20160066239A (en) | 2014-12-02 | 2014-12-02 | Preparation method of tungsten sputtering target and the tungsten sputtering target prepared thereby |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| KR20160066239A true KR20160066239A (en) | 2016-06-10 |
Family
ID=56190596
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR1020140170337A KR20160066239A (en) | 2014-12-02 | 2014-12-02 | Preparation method of tungsten sputtering target and the tungsten sputtering target prepared thereby |
Country Status (1)
| Country | Link |
|---|---|
| KR (1) | KR20160066239A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108907211A (en) * | 2018-08-16 | 2018-11-30 | 北京科技大学 | A method of preparing large scale molybdenum plate blank |
| CN109047780A (en) * | 2018-08-16 | 2018-12-21 | 北京科技大学 | A method of preparing high-compactness tungsten sintered article |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20100139152A (en) | 2008-06-02 | 2010-12-31 | 제이엑스 닛코 닛세키 킨조쿠 가부시키가이샤 | Tungsten sintered material sputtering target |
-
2014
- 2014-12-02 KR KR1020140170337A patent/KR20160066239A/en not_active Application Discontinuation
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20100139152A (en) | 2008-06-02 | 2010-12-31 | 제이엑스 닛코 닛세키 킨조쿠 가부시키가이샤 | Tungsten sintered material sputtering target |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108907211A (en) * | 2018-08-16 | 2018-11-30 | 北京科技大学 | A method of preparing large scale molybdenum plate blank |
| CN109047780A (en) * | 2018-08-16 | 2018-12-21 | 北京科技大学 | A method of preparing high-compactness tungsten sintered article |
| CN109047780B (en) * | 2018-08-16 | 2021-09-21 | 北京科技大学 | Method for preparing high-density tungsten sintered product |
| CN108907211B (en) * | 2018-08-16 | 2021-10-08 | 北京科技大学 | Method for preparing large-size molybdenum plate blank |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI545214B (en) | Tungsten target manufacturing method | |
| KR20160149720A (en) | Preparation method of sputtering target and the sputtering target prepared thereby | |
| JP2023076733A (en) | tungsten sputtering target | |
| JP3819863B2 (en) | Silicon sintered body and manufacturing method thereof | |
| JP6293359B2 (en) | Oxide sintered body and sputtering target comprising the oxide sintered body | |
| JP6285076B2 (en) | Oxide sintered body and sputtering target comprising the oxide sintered body | |
| KR20160066239A (en) | Preparation method of tungsten sputtering target and the tungsten sputtering target prepared thereby | |
| KR20140073570A (en) | Sputtering target and method for producing same | |
| JP5884001B1 (en) | Oxide sintered body and sputtering target comprising the oxide sintered body | |
| KR102444340B1 (en) | Method for producing translucent yttria by hot press sintering | |
| JP2001098359A (en) | MANUFACTURE OF Mg-CONTAINING ITO SPUTTERING TARGET AND Mg-CONTAINING ITO EVAPORATION MATERIAL | |
| JP4403591B2 (en) | Conductive metal oxide sintered body and use thereof | |
| KR20150070608A (en) | Preparation method of tungsten sputtering targets for semiconductors and the tungsten sputtering target prepared thereby | |
| KR20170016090A (en) | Metal sputtering target and method for manufacturing the same | |
| KR101500108B1 (en) | Tantalum sputtering target with a fine grain size and method of preparing the same | |
| JPH05222525A (en) | Production of tungsten target for semiconductor | |
| JP6537715B2 (en) | Al2O3 sputtering target and method of manufacturing the same | |
| KR20160123134A (en) | Preparation method of tungsten sputtering target and the thngsten sputtering target prepared thereby | |
| KR20170044343A (en) | Preparation method of reuse tungsten target and the reuse tungsten target prepared thereby | |
| KR20160073216A (en) | Manufacturing method of nickel alloy targetfor semiconductor and nickel alloy target for semiconductor manufactured thereby | |
| CN111836914A (en) | Sputtering target and method for producing sputtering target | |
| JPH04308048A (en) | Production of porous tungsten material | |
| KR101605633B1 (en) | Preparation method of ta target for semiconductors and the tantalum sputtering target prepared thereby | |
| KR20160067490A (en) | Refurbishing method of tungsten spent target and reuse tungsten target for forming wiring and electrode prepared thereby | |
| TW201716353A (en) | Licoo2-containing sintered compact, licoo2-containing sputtering target, and licoo2-containing sintered compact manufacturing method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A201 | Request for examination | ||
| E902 | Notification of reason for refusal | ||
| E601 | Decision to refuse application |