CN111893312A - Method for recovering precious metal from residual brazing precious metal target - Google Patents
Method for recovering precious metal from residual brazing precious metal target Download PDFInfo
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- CN111893312A CN111893312A CN202010675437.0A CN202010675437A CN111893312A CN 111893312 A CN111893312 A CN 111893312A CN 202010675437 A CN202010675437 A CN 202010675437A CN 111893312 A CN111893312 A CN 111893312A
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- 238000000034 method Methods 0.000 title claims abstract description 25
- 239000010970 precious metal Substances 0.000 title claims abstract description 20
- 238000005219 brazing Methods 0.000 title claims abstract description 7
- 229910000510 noble metal Inorganic materials 0.000 claims abstract description 31
- 239000002253 acid Substances 0.000 claims abstract description 26
- 229910000679 solder Inorganic materials 0.000 claims abstract description 14
- 238000011084 recovery Methods 0.000 claims abstract description 10
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 6
- 238000001035 drying Methods 0.000 claims abstract description 6
- 238000004140 cleaning Methods 0.000 claims abstract description 3
- 238000000053 physical method Methods 0.000 claims abstract description 3
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 26
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 14
- 229910052709 silver Inorganic materials 0.000 claims description 14
- 239000004332 silver Substances 0.000 claims description 14
- 229910052697 platinum Inorganic materials 0.000 claims description 13
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 12
- 229910052737 gold Inorganic materials 0.000 claims description 12
- 239000010931 gold Substances 0.000 claims description 12
- 229910052738 indium Inorganic materials 0.000 claims description 12
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 claims description 12
- 238000002386 leaching Methods 0.000 claims description 12
- 238000010438 heat treatment Methods 0.000 claims description 9
- 239000013077 target material Substances 0.000 claims description 8
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 6
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 4
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 4
- 229910017604 nitric acid Inorganic materials 0.000 claims description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 3
- 229910000881 Cu alloy Inorganic materials 0.000 claims description 3
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 3
- 239000010949 copper Substances 0.000 claims description 3
- 229910052707 ruthenium Inorganic materials 0.000 claims description 3
- 229910052741 iridium Inorganic materials 0.000 claims description 2
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 claims description 2
- 238000002844 melting Methods 0.000 claims description 2
- 230000008018 melting Effects 0.000 claims description 2
- 229910052763 palladium Inorganic materials 0.000 claims description 2
- 229910052703 rhodium Inorganic materials 0.000 claims description 2
- 239000010948 rhodium Substances 0.000 claims description 2
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 claims description 2
- 238000000926 separation method Methods 0.000 claims description 2
- 238000012545 processing Methods 0.000 abstract description 6
- 238000004064 recycling Methods 0.000 abstract description 5
- 238000007664 blowing Methods 0.000 abstract description 4
- 238000005477 sputtering target Methods 0.000 abstract description 3
- 238000005265 energy consumption Methods 0.000 abstract description 2
- 238000011112 process operation Methods 0.000 abstract description 2
- 239000000243 solution Substances 0.000 description 13
- 239000000463 material Substances 0.000 description 6
- 238000005406 washing Methods 0.000 description 6
- 238000003466 welding Methods 0.000 description 6
- 229910052751 metal Inorganic materials 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 239000012535 impurity Substances 0.000 description 4
- 239000004065 semiconductor Substances 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 239000004744 fabric Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 238000004544 sputter deposition Methods 0.000 description 3
- 239000008399 tap water Substances 0.000 description 3
- 235000020679 tap water Nutrition 0.000 description 3
- 239000010409 thin film Substances 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000010408 film Substances 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 239000007800 oxidant agent Substances 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 239000003513 alkali Substances 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001755 magnetron sputter deposition Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
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Classifications
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B11/00—Obtaining noble metals
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
The invention discloses a method for recovering noble metal from a brazing noble metal residual target, belonging to the technical field of sputtering target processing, which comprises the following steps: s1), providing a target assembly, wherein the target assembly comprises a noble metal target surface and a back plate brazed with the target surface, and the target surface of the target is separated from the back plate by using a physical method; s2) repeatedly immersing the noble metal target surface into the acid solution to completely separate the solder from the target surface; s3) cleaning the precious metal target surface in an ultrasonic cleaner, then rinsing in absolute ethyl alcohol and drying by blowing to obtain the precious metal with the same purity as the residual target before use. The method provided by the invention can realize the maximization of the recycling of the residual noble metal target, the recovery rate reaches more than 99.8 percent, the noble metal with the same purity as the residual target before use is obtained, the noble metal can be directly smelted and reprocessed, the recovery rate is high, the process operation is simple, the energy consumption is low, and meanwhile, the separated back plate can be welded with the newly processed noble metal target surface for recycling, so that the cost is saved.
Description
Technical Field
The invention belongs to the technical field of sputtering target processing, and particularly relates to a method for recovering precious metals from a brazing precious metal residual target.
Background
With the development of electronic information and emerging high technology industries, the application of thin film science is increasingly widespread. The noble metal has good chemical stability, high electrical conductivity and thermal conductivity, and unique electrical, magnetic and optical properties, and is widely applied to the preparation of high-performance thin film materials, and various high-purity elemental noble metals, novel alloys and compound functional thin films are continuously developed. Noble metal targets commonly used in semiconductor fabrication include metals and alloys such as gold, silver, platinum, and ruthenium. With the continuous progress and upgrade of the semiconductor industry technology in China, the noble metal target is used as an important support material in the process, the demand of the noble metal target is larger and larger, but the noble metal primary resource is few, the noble metal primary resource is not uniformly distributed, and meanwhile, because the quality requirements of the sputtering target and the sputtering film for the semiconductor are the highest in all industries, the noble metal target has strict requirements on the aspects of target purity, microstructure control, the overall quality consistency of target components and the like. Compared with the foreign countries, the manufacturing, processing and research and development of domestic precious metal processing enterprises have a certain gap, and the high-purification, refinement and high-efficiency deep processing technology of precious metals is urgently needed to be improved, so that the high added value and high-efficiency utilization of the metals are realized.
The magnetron sputtering process in the semiconductor manufacturing has high quality requirements on the target material and the film, so that the utilization rate of the target material is low and is usually within 30 percent, and particularly for the noble metal target material, if the residual high-purity residual target is treated by common waste materials, the rare and noble materials are greatly wasted. The value-added service of recycling and processing the residual target is urgently needed, the material utilization efficiency is effectively increased, and resources are saved.
At present, the recovery method in the prior art is to soak the target assembly in a strong alkaline solution, and after the backing plate is dissolved, remove the residual backing plate material, undissolved reaction products and metal impurities of the target under the condition of strong acid and strong oxidant, thereby achieving the purpose of recovering the target surface. However, the method is only suitable for targets with amphoteric metal backing plates, and the target backing plates are completely dissolved and cannot be recycled, thereby causing waste.
Disclosure of Invention
In order to solve the technical problem, the invention provides a method for recovering precious metal from a brazing precious metal residual target, which comprises the following steps:
s1), providing a target assembly, wherein the target assembly comprises a noble metal target surface and a back plate brazed with the target surface, and the target surface of the target is separated from the back plate by using a physical method;
s2) repeatedly immersing the noble metal target surface into the acid solution to completely separate the solder from the target surface;
s3) cleaning the precious metal target surface in an ultrasonic cleaner, then rinsing in absolute ethyl alcohol and drying to obtain precious metal with the same purity as the residual target before use;
the target surface of the target material is made of gold, silver, platinum, ruthenium, palladium, rhodium or iridium; the back plate is made of copper or copper alloy; the brazing solder is made of indium; the recovery rate of the noble metal reaches more than 99.8 percent.
The physical separation method in the step S1) is as follows: and providing a heating table, placing the target assembly on the heating table, heating to 180-220 ℃, melting the solder, separating the noble metal target surface from the back plate, wherein the size and the performance of the separated back plate are the same as those of the residual target before use.
The acid solution in the step S2) is nitric acid or sulfuric acid.
The volume fraction of the acid solution in the step S2) is 35-52%.
The temperature of the acid solution in the step S2) is 0-70 ℃.
The acid leaching time in the step S2) is 5-60S, and the acid leaching times are 1-3.
Advantageous effects
1. The method provided by the invention can realize the maximization of the recycling of the residual noble metal target, obtain the noble metal with the same purity as the residual target before use, can be directly smelted and reprocessed, and has the recovery rate of more than 99.8 percent;
2. the back plate material of the method is copper and copper alloy, thereby overcoming the limitation that the prior art can only be amphoteric metal;
3. in the method, the back plate is separated from the target surface, and the noble metal target surface with the same purity as the residual target before use can be obtained without adding a strong alkali solution and a strong oxidant in the process of purifying the target surface, so that the method is more in line with the practical application value and the concept of green chemistry;
4. according to the method, the volume fraction of the selected acid solution is 35-52%, the temperature of the acid solution is 0-70 ℃, and the reaction rate of the acid solution is effectively increased;
5. according to the method, the acid leaching time is 5-60 s, and the acid leaching times are 1-3 times, so that the target can be prevented from being corroded by an acid solution while the indium solder on the target surface is completely dissolved;
6. the method has simple process operation and low energy consumption, and simultaneously, the separated back plate can be welded with the newly processed noble metal target surface for recycling, thereby saving the cost.
Drawings
FIG. 1 is a schematic flow diagram of a method for recovering precious metals from a brazed precious metal residual target according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention and the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Taking XL Quantum high-purity gold target for Varian machine as an example: the purity of the high-purity gold target surface is 99.996% (>4N), the weight of the finished product is 4207.034g, the consumption weight of 841.407g by sputtering after use is 3526 g, and the theoretical residual weight of the target surface is 3365.627 g; the noble metal recovery process was carried out as shown in the schematic flow diagram of fig. 1:
s1) heating the indium welding XL Quantum high-purity gold residual target at 210 ℃ to melt the indium solder and separate the high-purity gold target surface from the back plate;
s2) immersing the high-purity gold target surface into a nitric acid solution with the volume fraction of 50% and the temperature of 60 ℃, carrying out acid leaching for 60S for 2 times, wiping the welding surface with dust-free cloth after each acid leaching, and separating the indium solder from the high-purity gold target surface;
s3) washing the noble metal target surface in tap water, then washing in absolute ethyl alcohol and drying by blowing, thus obtaining high-purity gold without impurity residues, wherein the purity of the gold in the original target material is the same.
The purity of the obtained high-purity gold is 99.994% (>4N), the actual weight is 3365.521g, and the recovery rate is 99.997%.
Example 2
Taking XL Quantum high-purity silver target for Varian machine as an example: the purity of the high-purity silver target surface is 99.994% (>4N), the weight of a finished product is 6863.465g, the weight is 1372.693g after the high-purity silver target surface is used, and the theoretical residual weight of the target surface is 5490.772 g;
s1) heating the indium welding XL Quantum high-purity silver residual target at 210 ℃ to melt the indium solder and separate the high-purity silver target surface from the back plate;
s2) immersing the high-purity silver target surface into a sulfuric acid solution with the volume fraction of 35% and the temperature of 45 ℃, carrying out acid leaching for 10S for 3 times, wiping the welding surface by using dust-free cloth after each acid leaching, and separating the indium solder from the high-purity silver target surface;
s3) washing the high-purity silver target surface in tap water, then washing in absolute ethyl alcohol and drying by blowing, thus obtaining the high-purity silver without impurity residues, wherein the purity of the silver in the original target material is the same.
The purity of the obtained high-purity silver is 99.993% (>4N), the actual weight is 5482.635g, and the recovery rate is 99.852%.
Example 3
Taking XL Quantum high-purity platinum target for Varian machine as an example: the purity of the high-purity platinum target surface is 99.998% (>4N), the weight of a finished product is 4417.978g, the consumption weight of 883.596g by sputtering after use is 883.596g, and the theoretical residual weight of the target surface is 3534.382 g;
s1) heating the indium welding XL Quantum high-purity platinum residual target at 210 ℃ to melt the indium solder, and separating the high-purity platinum target surface from the back plate;
s2) immersing the high-purity platinum target surface into a nitric acid solution with the volume fraction of 50% and the temperature of 65 ℃, carrying out acid leaching for 60S for 1 time, wiping the welding surface by using dust-free cloth after acid leaching, and separating the indium solder from the high-purity platinum target surface;
s3) washing the high-purity platinum target surface in tap water, then washing in absolute ethyl alcohol and drying by blowing, thus obtaining high-purity platinum without impurity residues, wherein the purity of the platinum in the original target material is the same.
The purity of the obtained high-purity platinum is 99.996% (>4N), the actual weight is 3534.295g, and the recovery rate is 99.998%.
Claims (6)
1. A method of recovering precious metals from a brazed precious metal stub target, comprising the steps of:
s1), providing a target assembly, wherein the target assembly comprises a noble metal target surface and a back plate brazed with the target surface, and the target surface of the target is separated from the back plate by using a physical method;
s2) repeatedly immersing the noble metal target surface into the acid solution to completely separate the solder from the target surface;
s3) cleaning the precious metal target surface in an ultrasonic cleaner, then rinsing in absolute ethyl alcohol and drying to obtain precious metal with the same purity as the residual target before use;
the target surface of the target material is made of gold, silver, platinum, ruthenium, palladium, rhodium or iridium; the back plate is made of copper or copper alloy; the brazing solder is made of indium; the recovery rate of the noble metal reaches more than 99.8 percent.
2. The method as claimed in claim 1, wherein the physical separation method in step S1) is: and providing a heating table, placing the target assembly on the heating table, heating to 180-220 ℃, melting the solder, separating the noble metal target surface from the back plate, wherein the size and the performance of the separated back plate are the same as those of the residual target before use.
3. The method as claimed in claim 1, wherein the acid solution in step S2) is nitric acid or sulfuric acid.
4. The method as claimed in claim 3, wherein the volume fraction of the acid solution in the step S2) is 35-52%.
5. The method as claimed in claim 3, wherein the acid solution temperature in the step S2) is 0-70 ℃.
6. The method according to claim 1, wherein the acid leaching time in step S2) is 5-60S, and the acid leaching times is 1-3.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010675437.0A CN111893312A (en) | 2020-07-14 | 2020-07-14 | Method for recovering precious metal from residual brazing precious metal target |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010675437.0A CN111893312A (en) | 2020-07-14 | 2020-07-14 | Method for recovering precious metal from residual brazing precious metal target |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW483937B (en) * | 2000-09-15 | 2002-04-21 | Ind Tech Res Inst | Recycle and reuse method of aluminum alloy sputter target material |
| US6461400B1 (en) * | 2000-04-12 | 2002-10-08 | Art J. Parker | Process for extracting quantities of precious metals |
| US20120103138A1 (en) * | 2009-05-26 | 2012-05-03 | Metaleach Limited | Method of oxidative leaching of sulfide ores and/or concentrates |
| TW201323621A (en) * | 2011-12-13 | 2013-06-16 | Shin Chung Chemical Co Ltd | Metal compound recycling method for waste target |
| CN109207729A (en) * | 2018-09-03 | 2019-01-15 | 宁波创润新材料有限公司 | A kind of sputtering target material recovery method |
| CN111004923A (en) * | 2019-12-13 | 2020-04-14 | 昆山全亚冠环保科技有限公司 | Preparation method and use method of precious metal recovery adsorption material |
-
2020
- 2020-07-14 CN CN202010675437.0A patent/CN111893312A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6461400B1 (en) * | 2000-04-12 | 2002-10-08 | Art J. Parker | Process for extracting quantities of precious metals |
| TW483937B (en) * | 2000-09-15 | 2002-04-21 | Ind Tech Res Inst | Recycle and reuse method of aluminum alloy sputter target material |
| US20120103138A1 (en) * | 2009-05-26 | 2012-05-03 | Metaleach Limited | Method of oxidative leaching of sulfide ores and/or concentrates |
| TW201323621A (en) * | 2011-12-13 | 2013-06-16 | Shin Chung Chemical Co Ltd | Metal compound recycling method for waste target |
| CN109207729A (en) * | 2018-09-03 | 2019-01-15 | 宁波创润新材料有限公司 | A kind of sputtering target material recovery method |
| CN111004923A (en) * | 2019-12-13 | 2020-04-14 | 昆山全亚冠环保科技有限公司 | Preparation method and use method of precious metal recovery adsorption material |
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