US20230323541A1 - Electroless copper plating solution - Google Patents
Electroless copper plating solution Download PDFInfo
- Publication number
- US20230323541A1 US20230323541A1 US18/035,806 US202118035806A US2023323541A1 US 20230323541 A1 US20230323541 A1 US 20230323541A1 US 202118035806 A US202118035806 A US 202118035806A US 2023323541 A1 US2023323541 A1 US 2023323541A1
- Authority
- US
- United States
- Prior art keywords
- copper plating
- electroless copper
- plating solution
- solution
- tellurium
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000007747 plating Methods 0.000 title claims abstract description 213
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 title claims abstract description 175
- 229910052802 copper Inorganic materials 0.000 title claims abstract description 175
- 239000010949 copper Substances 0.000 title claims abstract description 175
- 230000008021 deposition Effects 0.000 claims abstract description 73
- 239000003381 stabilizer Substances 0.000 claims abstract description 31
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 28
- JPVYNHNXODAKFH-UHFFFAOYSA-N Cu2+ Chemical compound [Cu+2] JPVYNHNXODAKFH-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910001431 copper ion Inorganic materials 0.000 claims abstract description 21
- 239000003638 chemical reducing agent Substances 0.000 claims abstract description 20
- 150000003498 tellurium compounds Chemical class 0.000 claims abstract description 19
- 239000004094 surface-active agent Substances 0.000 claims abstract description 17
- 150000001879 copper Chemical class 0.000 claims abstract description 16
- 230000007935 neutral effect Effects 0.000 claims abstract description 16
- 150000001491 aromatic compounds Chemical class 0.000 claims abstract description 14
- 239000008139 complexing agent Substances 0.000 claims abstract description 14
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 14
- 229910052714 tellurium Inorganic materials 0.000 claims description 23
- PORWMNRCUJJQNO-UHFFFAOYSA-N tellurium atom Chemical compound [Te] PORWMNRCUJJQNO-UHFFFAOYSA-N 0.000 claims description 23
- 239000002738 chelating agent Substances 0.000 claims description 10
- ABLZXFCXXLZCGV-UHFFFAOYSA-N Phosphorous acid Chemical compound OP(O)=O ABLZXFCXXLZCGV-UHFFFAOYSA-N 0.000 claims description 9
- UORVGPXVDQYIDP-UHFFFAOYSA-N borane Chemical compound B UORVGPXVDQYIDP-UHFFFAOYSA-N 0.000 claims description 7
- 239000003945 anionic surfactant Substances 0.000 claims description 6
- 150000003839 salts Chemical class 0.000 claims description 6
- 229910000085 borane Inorganic materials 0.000 claims description 4
- YMUZFVVKDBZHGP-UHFFFAOYSA-N dimethyl telluride Chemical compound C[Te]C YMUZFVVKDBZHGP-UHFFFAOYSA-N 0.000 claims description 4
- 150000001412 amines Chemical group 0.000 claims description 3
- RJTANRZEWTUVMA-UHFFFAOYSA-N boron;n-methylmethanamine Chemical compound [B].CNC RJTANRZEWTUVMA-UHFFFAOYSA-N 0.000 claims description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 2
- VDTVZBCTOQDZSH-UHFFFAOYSA-N borane N-ethylethanamine Chemical compound B.CCNCC VDTVZBCTOQDZSH-UHFFFAOYSA-N 0.000 claims description 2
- GKFJEDWZQZKYHV-UHFFFAOYSA-N borane;2-methylpropan-2-amine Chemical compound B.CC(C)(C)N GKFJEDWZQZKYHV-UHFFFAOYSA-N 0.000 claims description 2
- WVMHLYQJPRXKLC-UHFFFAOYSA-N borane;n,n-dimethylmethanamine Chemical compound B.CN(C)C WVMHLYQJPRXKLC-UHFFFAOYSA-N 0.000 claims description 2
- VEWFZHAHZPVQES-UHFFFAOYSA-N boron;n,n-diethylethanamine Chemical compound [B].CCN(CC)CC VEWFZHAHZPVQES-UHFFFAOYSA-N 0.000 claims description 2
- FXADMRZICBQPQY-UHFFFAOYSA-N orthotelluric acid Chemical compound O[Te](O)(O)(O)(O)O FXADMRZICBQPQY-UHFFFAOYSA-N 0.000 claims description 2
- LAJZODKXOMJMPK-UHFFFAOYSA-N tellurium dioxide Chemical compound O=[Te]=O LAJZODKXOMJMPK-UHFFFAOYSA-N 0.000 claims description 2
- IIXQANVWKBCLEB-UHFFFAOYSA-N tellurium trioxide Chemical compound O=[Te](=O)=O IIXQANVWKBCLEB-UHFFFAOYSA-N 0.000 claims description 2
- SITVSCPRJNYAGV-UHFFFAOYSA-N tellurous acid Chemical compound O[Te](O)=O SITVSCPRJNYAGV-UHFFFAOYSA-N 0.000 claims description 2
- 239000000203 mixture Substances 0.000 abstract description 22
- 238000000151 deposition Methods 0.000 description 70
- 230000000052 comparative effect Effects 0.000 description 21
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 20
- 238000012790 confirmation Methods 0.000 description 16
- 229910052782 aluminium Inorganic materials 0.000 description 13
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 13
- XERQTZLDFHNZIC-UHFFFAOYSA-L disodium;tellurate Chemical compound [Na+].[Na+].[O-][Te]([O-])(=O)=O XERQTZLDFHNZIC-UHFFFAOYSA-L 0.000 description 13
- -1 borane compound Chemical class 0.000 description 8
- 238000000034 method Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 239000000758 substrate Substances 0.000 description 5
- 239000002253 acid Substances 0.000 description 4
- DZBUGLKDJFMEHC-UHFFFAOYSA-N acridine Chemical compound C1=CC=CC2=CC3=CC=CC=C3N=C21 DZBUGLKDJFMEHC-UHFFFAOYSA-N 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 229910052787 antimony Inorganic materials 0.000 description 3
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 229910000365 copper sulfate Inorganic materials 0.000 description 3
- ARUVKPQLZAKDPS-UHFFFAOYSA-L copper(II) sulfate Chemical compound [Cu+2].[O-][S+2]([O-])([O-])[O-] ARUVKPQLZAKDPS-UHFFFAOYSA-L 0.000 description 3
- RAXXELZNTBOGNW-UHFFFAOYSA-N imidazole Natural products C1=CNC=N1 RAXXELZNTBOGNW-UHFFFAOYSA-N 0.000 description 3
- 230000002829 reductive effect Effects 0.000 description 3
- KDCGOANMDULRCW-UHFFFAOYSA-N 7H-purine Chemical compound N1=CNC2=NC=NC2=C1 KDCGOANMDULRCW-UHFFFAOYSA-N 0.000 description 2
- LRFVTYWOQMYALW-UHFFFAOYSA-N 9H-xanthine Chemical compound O=C1NC(=O)NC2=C1NC=N2 LRFVTYWOQMYALW-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- PVNIIMVLHYAWGP-UHFFFAOYSA-N Niacin Chemical compound OC(=O)C1=CC=CN=C1 PVNIIMVLHYAWGP-UHFFFAOYSA-N 0.000 description 2
- KYQCOXFCLRTKLS-UHFFFAOYSA-N Pyrazine Chemical compound C1=CN=CC=N1 KYQCOXFCLRTKLS-UHFFFAOYSA-N 0.000 description 2
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 description 2
- SMWDFEZZVXVKRB-UHFFFAOYSA-N Quinoline Chemical compound N1=CC=CC2=CC=CC=C21 SMWDFEZZVXVKRB-UHFFFAOYSA-N 0.000 description 2
- DBMJMQXJHONAFJ-UHFFFAOYSA-M Sodium laurylsulphate Chemical compound [Na+].CCCCCCCCCCCCOS([O-])(=O)=O DBMJMQXJHONAFJ-UHFFFAOYSA-M 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- ISAKRJDGNUQOIC-UHFFFAOYSA-N Uracil Chemical compound O=C1C=CNC(=O)N1 ISAKRJDGNUQOIC-UHFFFAOYSA-N 0.000 description 2
- DRTQHJPVMGBUCF-XVFCMESISA-N Uridine Chemical compound O[C@@H]1[C@H](O)[C@@H](CO)O[C@H]1N1C(=O)NC(=O)C=C1 DRTQHJPVMGBUCF-XVFCMESISA-N 0.000 description 2
- OIRDTQYFTABQOQ-KQYNXXCUSA-N adenosine Chemical compound C1=NC=2C(N)=NC=NC=2N1[C@@H]1O[C@H](CO)[C@@H](O)[C@H]1O OIRDTQYFTABQOQ-KQYNXXCUSA-N 0.000 description 2
- 229910000410 antimony oxide Inorganic materials 0.000 description 2
- IOJUPLGTWVMSFF-UHFFFAOYSA-N benzothiazole Chemical compound C1=CC=C2SC=NC2=C1 IOJUPLGTWVMSFF-UHFFFAOYSA-N 0.000 description 2
- RYYVLZVUVIJVGH-UHFFFAOYSA-N caffeine Chemical compound CN1C(=O)N(C)C(=O)C2=C1N=CN2C RYYVLZVUVIJVGH-UHFFFAOYSA-N 0.000 description 2
- 229910010293 ceramic material Inorganic materials 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- JZCCFEFSEZPSOG-UHFFFAOYSA-L copper(II) sulfate pentahydrate Chemical compound O.O.O.O.O.[Cu+2].[O-]S([O-])(=O)=O JZCCFEFSEZPSOG-UHFFFAOYSA-L 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- NFDRPXJGHKJRLJ-UHFFFAOYSA-N edtmp Chemical compound OP(O)(=O)CN(CP(O)(O)=O)CCN(CP(O)(O)=O)CP(O)(O)=O NFDRPXJGHKJRLJ-UHFFFAOYSA-N 0.000 description 2
- 238000007772 electroless plating Methods 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- UYTPUPDQBNUYGX-UHFFFAOYSA-N guanine Chemical compound O=C1NC(N)=NC2=C1N=CN2 UYTPUPDQBNUYGX-UHFFFAOYSA-N 0.000 description 2
- FDGQSTZJBFJUBT-UHFFFAOYSA-N hypoxanthine Chemical compound O=C1NC=NC2=C1NC=N2 FDGQSTZJBFJUBT-UHFFFAOYSA-N 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- YAPQBXQYLJRXSA-UHFFFAOYSA-N theobromine Chemical compound CN1C(=O)NC(=O)C2=C1N=CN2C YAPQBXQYLJRXSA-UHFFFAOYSA-N 0.000 description 2
- ZFXYFBGIUFBOJW-UHFFFAOYSA-N theophylline Chemical compound O=C1N(C)C(=O)N(C)C2=C1NC=N2 ZFXYFBGIUFBOJW-UHFFFAOYSA-N 0.000 description 2
- RWQNBRDOKXIBIV-UHFFFAOYSA-N thymine Chemical compound CC1=CNC(=O)NC1=O RWQNBRDOKXIBIV-UHFFFAOYSA-N 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- NWONKYPBYAMBJT-UHFFFAOYSA-L zinc sulfate Chemical compound [Zn+2].[O-]S([O-])(=O)=O NWONKYPBYAMBJT-UHFFFAOYSA-L 0.000 description 2
- JYEUMXHLPRZUAT-UHFFFAOYSA-N 1,2,3-triazine Chemical compound C1=CN=NN=C1 JYEUMXHLPRZUAT-UHFFFAOYSA-N 0.000 description 1
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- SGZOTVJMWSLUAK-UHFFFAOYSA-N 2h-quinoline-1,2-dicarboxylic acid Chemical compound C1=CC=C2N(C(O)=O)C(C(=O)O)C=CC2=C1 SGZOTVJMWSLUAK-UHFFFAOYSA-N 0.000 description 1
- SXDLHJVLSDPNEL-UHFFFAOYSA-N 3-n,6-n-dimethylacridine-3,6-diamine Chemical compound C1=CC(NC)=CC2=NC3=CC(NC)=CC=C3C=C21 SXDLHJVLSDPNEL-UHFFFAOYSA-N 0.000 description 1
- MWVTWFVJZLCBMC-UHFFFAOYSA-N 4,4'-bipyridine Chemical group C1=NC=CC(C=2C=CN=CC=2)=C1 MWVTWFVJZLCBMC-UHFFFAOYSA-N 0.000 description 1
- DHDHJYNTEFLIHY-UHFFFAOYSA-N 4,7-diphenyl-1,10-phenanthroline Chemical compound C1=CC=CC=C1C1=CC=NC2=C1C=CC1=C(C=3C=CC=CC=3)C=CN=C21 DHDHJYNTEFLIHY-UHFFFAOYSA-N 0.000 description 1
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- 239000002126 C01EB10 - Adenosine Substances 0.000 description 1
- OCUCCJIRFHNWBP-IYEMJOQQSA-L Copper gluconate Chemical compound [Cu+2].OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C([O-])=O.OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C([O-])=O OCUCCJIRFHNWBP-IYEMJOQQSA-L 0.000 description 1
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- 150000003212 purines Chemical class 0.000 description 1
- PBMFSQRYOILNGV-UHFFFAOYSA-N pyridazine Chemical compound C1=CC=NN=C1 PBMFSQRYOILNGV-UHFFFAOYSA-N 0.000 description 1
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 1
- 150000003222 pyridines Chemical class 0.000 description 1
- 150000003230 pyrimidines Chemical class 0.000 description 1
- MCJGNVYPOGVAJF-UHFFFAOYSA-N quinolin-8-ol Chemical compound C1=CN=C2C(O)=CC=CC2=C1 MCJGNVYPOGVAJF-UHFFFAOYSA-N 0.000 description 1
- 150000003248 quinolines Chemical class 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 229960004559 theobromine Drugs 0.000 description 1
- 229960000278 theophylline Drugs 0.000 description 1
- ZEMGGZBWXRYJHK-UHFFFAOYSA-N thiouracil Chemical compound O=C1C=CNC(=S)N1 ZEMGGZBWXRYJHK-UHFFFAOYSA-N 0.000 description 1
- 229940113082 thymine Drugs 0.000 description 1
- 229940035893 uracil Drugs 0.000 description 1
- DRTQHJPVMGBUCF-UHFFFAOYSA-N uracil arabinoside Natural products OC1C(O)C(CO)OC1N1C(=O)NC(=O)C=C1 DRTQHJPVMGBUCF-UHFFFAOYSA-N 0.000 description 1
- 229940045145 uridine Drugs 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
- 229940075420 xanthine Drugs 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
Classifications
-
- 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
- C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
- C23C18/16—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by reduction or substitution, e.g. electroless plating
- C23C18/31—Coating with metals
- C23C18/38—Coating with copper
- C23C18/40—Coating with copper using reducing agents
Definitions
- the present application relates to an electroless copper plating solution, particularly to a reducing electroless copper plating solution used in a neutral range.
- an electroless copper plating solution that uses formaldehyde as a reducing agent for copper ions.
- formaldehyde has an irritating odor that deteriorates the working environment and causes adverse effects on the human body.
- the electroless copper plating solution using formaldehyde is strongly alkaline, and thus the use of the electroless copper plating solution is difficult especially when the object to be plated is aluminum, aluminum alloy, or the like.
- Patent Literature 1 discloses “an electroless copper plating bath having a pH of 4 to 9, containing a water-soluble copper salt, amino borane or a substituted derivative thereof as a reducing agent, and no formaldehyde, the electroless copper plating bath containing polyaminopolyphosphonic acid as a complexing agent, an anionic surfactant, an antimony compound, and a nitrogen-containing aromatic compound”.
- the first problem is that if the electroless copper plating bath disclosed in Patent Literature 1 is left in a plating bath for a long time after use, copper tends to deposit on the bottom of the bath, stirring jigs, and the like, resulting in a high tendency to have a lack of solution stability as a plating solution;
- the second problem is that an electroless copper plating layer formed using the electroless copper plating bath disclosed in Patent Literature 1 tends to have a non-uniform appearance;
- the third problem is that when plating is performed on an aluminum material using the electroless copper plating bath disclosed in Patent Literature 1, the copper plating layer tends to swell even if the aluminum itself is not damaged, resulting in a tendency for pits to occur.
- an object of the present application is to provide an electroless copper plating solution with excellent solution stability and easy composition control, which does not cause the above-mentioned problems.
- the electroless copper plating solution according to the present application is a reducing electroless copper plating solution used in a neutral range that contains a copper salt serving as a copper ion supply source, a complexing agent for chelating copper ions, a reducing agent, a surfactant, an aromatic compound containing nitrogen, and contains a tellurium compound serving as a deposition stabilizer, and that has a solution pH of 6 to 9.
- the tellurium compound serving as a deposition stabilizer is preferably used in a concentration range of 0.1 mg/L to 100 mg/L in terms of tellurium.
- the complexing agent for chelating copper ions is preferably a phosphonic acid-based chelating agent is used in a concentration range of 0.1 to 10 times the number of moles of copper.
- the reducing agent is preferably amine borane or a derivative thereof.
- the surfactant is preferably an anionic surfactant used in a concentration range of 0.01 mg/L to 1500 mg/L.
- the aromatic compound containing nitrogen is preferably used in a concentration range of 0.01 mg/L to 1000 mg/L.
- the electroless copper plating solution according to the present application contains a tellurium compound serving as a deposition stabilizer for the electroless copper plating solution, thereby dramatically improving the solution stability as a plating solution even though it is used in a neutral range without containing formaldehyde.
- a change in the composition of the plating solution during plating operation is small, a stable copper plating layer can be formed even if the composition is slightly changed, and it becomes possible to obtain layer thickness uniformity and uniform appearance quality of the copper plating layer.
- unnecessary copper deposition does not occur while a plating solution is less deteriorated, making it possible to prolong the life of the solution.
- aluminum itself is not damaged when the solution is plated on an aluminum material, and plating defects such as blisters and pits in the plating layer can be efficiently eliminated.
- Embodiments of the electroless copper plating solution according to the present application and electroless copper plating methods using the same will be described below.
- the electroless copper plating solution according to the present application is an electroless copper plating solution used in a neutral range, and this electroless copper plating solution contains a tellurium compound serving as a deposition stabilizer in terms of a component and has a solution pH of 6 to 9.
- the solution pH of the electroless copper plating solution will be described below, and then each component will be described.
- the solution pH is preferably 6.0 to 9.0.
- the electroless copper plating solution is in an acidic range, which is not preferable because the effect of components such as the reducing agents described below is likely to decrease, making it difficult to prolong the life of the electroless copper plating solution.
- the solution pH is more than 9.0, the electroless copper plating solution is in an alkaline range, which is not preferable because the surface of the object to be plated, such as an aluminum material or a ceramic material, is more likely to be damaged.
- the solution pH is more preferably 6.5 to 8.5, which is even closer to neutral, and in this case, the damage to the object to be plated can be prevented more reliably.
- hydrochloric acid, sulfuric acid, or the like may be used to adjust the solution pH to the acid side while sodium hydroxide, potassium hydroxide, or the like may be used to adjust the solution pH to the alkali side.
- the tellurium compound serving as a deposition stabilizer is used.
- the tellurium compound include any one or more of telluric acid and a salt thereof, tellurous acid and a salt thereof, tellurium dioxide, tellurium trioxide, tellurium chloride, and dimethyl telluride.
- the tellurium compound serving as a deposition stabilizer is preferably contained in the electroless copper plating solution in a concentration range of 0.1 mg/L to 100 mg/L in terms of tellurium.
- the content of the tellurium compound is less than 0.1 mg/L in terms of concentration of tellurium, the solution stability of the electroless copper plating solution cannot be improved, the lifetime extension of the plating solution cannot be achieved, and the characteristics of the plating solution vary due to the change in the composition, making it difficult to use the electroless copper plating solution for a long time, which is not preferable.
- the content of the tellurium compound is more than 100 mg/L in concentration as tellurium, the phenomenon that copper deposition is markedly reduced is observed, which is not preferable because rapid copper plating layer formation becomes difficult.
- the content of the tellurium compound is more preferably in the concentration range of 0.3 mg/L to 70 mg/L in terms of concentration of tellurium.
- the tellurium compound is most preferably contained in the concentration range of 0.5 mg/L to 50 mg/L in terms of tellurium.
- Copper ion supply source The copper salt serving as a copper ion supply source is used in the electroless copper plating solution according to the present application.
- the copper salt include any one or more of water-soluble copper salts such as copper sulfate, copper nitrate, copper chloride, copper acetate, copper citrate, copper tartrate, copper gluconate, and hydrates thereof.
- two or more copper salts of the present application can be simultaneously used in combination, and there is no particular limitation on the mixing ratio of two or more copper salts as long as the amount of copper ions is in the following range.
- the most widely available is copper sulfate (copper sulfate pentahydrate) or a combination of copper sulfate and copper hydrochloride.
- the content of the copper salt is preferably in the concentration range of 0.01 mol/L to 1 mol/L in terms of concentration of copper.
- the content of the copper salt in the electroless copper plating solution according to the present application is less than 0.01 mol/L in terms of concentration of copper because the copper deposition rate is remarkably decreased, the time required for operation becomes long, and the productivity required for industrial purposes cannot be obtained, which is not preferable.
- the content of copper salt is more than 1 mol/L in terms of concentration of copper, the copper deposition rate is not improved, but rather the appearance defects of the formed copper plating layer tend to increase, which is not preferable.
- the content of the copper salt is preferably in the concentration range of 0.02 mol/L to 0.5 mol/L in terms of concentration of copper.
- the electroless copper plating solution according to the present application is used in the neutral range, and it is preferable to use a phosphonic acid-based chelating agent as the complexing agent. This is because the phosphonic acid-based chelating agent easily forms a complex of copper ions in the neutral range.
- the phosphonic acid-based chelating agent includes 1-hydroxyethane-1,1-diphosphonic acid, N,N,N′,N′-ethylenediaminetetrakis(methylenephosphonic acid), nitrilotris(methylenephosphonic acid), diethylenediaminepenta(methylenephosphonic acid), diethylenetriaminepenta(methylenephosphonic acid), bis(hexamethylenetriaminepenta(methylenephosphonic acid)), glycine-N,N-bis(methylenephosphonic acid), and salts thereof, and one or more of them can be used simultaneously.
- the amount of the complexing agent added is determined by the copper content in the electroless copper plating solution.
- the phosphonic acid-based chelating agent as a complexing agent is preferably used in a concentration range of 0.1 to 10 times the number of moles of copper in the electroless copper plating solution.
- concentration of the phosphonic acid-based chelating agent is less than 0.1 times the number of moles of copper, copper ions cannot be sufficiently complexed, and solution stability as an electroless copper plating solution cannot be ensured, which is not preferable.
- the concentration of the phosphonic acid-based chelating agent is more than 10 times the number of moles of copper
- the amount of the chelating agent is more than the amount required for the complexation of copper ions, which is not preferable because it wastes resources and also causes the appearance quality of the copper plating layer to deteriorate.
- Reducing agent Various reducing agents can be used for copper ions. In the case of the electroless copper plating solution according to the present application, however, since it is used in the neutral range, it is preferable to use amine borane or a derivative thereof as a reducing agent usable in the neutral range in order to ensure the solution stability. More specifically, any one or more of dimethylamine borane, diethylamine borane, tert-butylamine borane, triethylamine borane, trimethylamine borane, and the like can be used. The concentration of this reducing agent is not particularly limited, but it is reasonable to set the concentration in the range of 0.01 mol/L to 0.5 mol/L.
- the concentration of the reducing agent is less than 0.01 mol/L, the copper deposition rate is slow, which is not preferable.
- the concentration of the reducing agent is more than 0.5 mol/L, it is not preferable because the copper deposition rate does not increase and is simply a waste of resources.
- Surfactant In the electroless copper plating solution according to the present application, it is preferable to use a surfactant for the purpose of improving the solution stability and improving the layer thickness uniformity and appearance quality of the plating layer to be formed. Especially in the case of an electroless copper plating solution used in the neutral range, it is preferable to use an anionic surfactant.
- anionic surfactants all the surfactants which are called “anionic surfactants” or “anionic surface-active agents” in the market can be used.
- examples include any one or more of alkylcarboxylic acid-based surfactants, naphthalene sulfonate formaldehyde condensates such as sodium salts of ⁇ -naphthalene sulfonate formalin condensate, polyoxyalkylene ether sulfates such as sodium polyoxyethylene lauryl ether sulfate and triethanolamine polyoxyethylene alkyl ether sulfate, and sodium dodecyl sulfate, but not special limitations are required.
- the concentration of the surfactant is not particularly limited, but it is reasonable to set the concentration in the range of 0.01 mg/L to 1500 mg/L.
- concentration of the surfactant is less than 0.01 mg/L, it is not preferable since the solution stability of the electroless copper plating solution does not improve, making it difficult to prolong the life of the plating solution, and the appearance quality of the copper plating layer tends to deteriorate.
- concentration of the surfactant is more than 1500 mg/L, there is no particular problem, but the solution stability is not further improved nor the appearance quality is improved. Besides, the bath control during the plating operation becomes complicated, which is not preferable.
- Aromatic compound containing nitrogen In the electroless copper plating solution according to the present application, an aromatic compound containing nitrogen (so-called a heterocyclic aromatic compound containing nitrogen) is used to stabilize copper deposition in electroless copper plating.
- the nitrogen-containing aromatic compounds include any one or more of: imidazole or substituted derivatives thereof; pyrazole or substituted derivatives thereof; oxazole or substituted derivatives thereof; thiazole or substituted derivatives thereof; pyrazine or substituted derivatives thereof; pyridazine or substituted derivatives thereof; triazine or substituted derivatives thereof; benzothiazole or substituted derivatives thereof; pyridines such as pyridine, 2,2′-dipyridyl, 4,4′-dipyridyl, nicotinic acid, nicotinamide, picolines, and lutidines, or substituted derivatives thereof; quinolines such as quinoline and hydroxyquinoline, or substituted derivatives thereof; acridines such
- the concentration of the aromatic compound containing nitrogen that is contained in the electroless copper plating solution according to the present application is preferably 0.01 mg/L to 1000 mg/L.
- concentration of the aromatic compound containing nitrogen is less than 0.01 mg/L, the effect as a deposition stabilizer for copper cannot be exhibited, which is not preferable because the appearance of the formed copper plating layer is also impaired.
- concentration of the aromatic compound containing nitrogen is more than 1000 mg/L, the solution stability of the electroless copper plating solution becomes excessive, which is not preferable because it causes a decrease in the copper deposition rate and an undeposited portion of the plating layer is generated.
- electroless copper plating method conventionally known electroless plating methods and conditions may be applied using the above-mentioned electroless copper plating solution. Therefore, it is considered unnecessary to describe the electroless copper plating method in detail here, and the electroless plating methods and conditions are described in Example.
- Example 1 the solution stability as a plating solution was confirmed after electroless copper plating was performed using an electroless copper plating solution containing a copper salt serving as a copper ion supply source, a complexing agent for chelating copper ions, a reducing agent, a surfactant, an aromatic compound containing nitrogen, and containing a tellurium compound serving as a deposition stabilizer, and having a solution pH of 7.7 and a solution temperature of 60° C.
- the evaluation of the solution stability as a plating solution is indicated by “ ⁇ ” when no deposition was observed on a part other than the object to be treated, by “ ⁇ ” when the deposition was slightly observed, and by “X” when the deposition was remarkably or decomposition of the plating solution occurred during plating, after the electroless copper plating solution is heated and plated while keeping the solution temperature constant, and then the electroless copper plating solution is left for 12 hours.
- Table 3 The results of this confirmation are shown in Table 3 below.
- Example 1 a substrate with an aluminum circuit (hereinafter simply referred to as a substrate), an object to be plated, was subjected to pretreatment under the conditions listed in Table 1 below (in the order from the top in the table), and then immersed in an electroless copper plating solution for 120 minutes to perform electroless copper plating, thereby forming a copper plating layer on the surface of the aluminum circuit pattern.
- Treatment Treatment step Name of bath condition Degreasing Melcleaner SC-7001 70° C., 30 secs Etching Melplate E-7121 70° C., 30 secs Conditioning Melplate Conditioner 7230 22° C., 20 secs Single zincate treatment Melplate FZ-7350 22° C., 20 secs Zinc stripping 20 wt % nitric acid 22° C., 10 secs Double zincate treatmen Melplate FBZ 22° C., 30 secs
- Example 1 an electroless copper plating solution having the composition shown below was prepared.
- Example 1 the deposition rate of the electroless copper plating layer, the plating appearance, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the copper plating layer after the plating layer was formed on the surface of the aluminum circuit pattern (hereinafter, also simply referred to as a pattern) on the substrate were confirmed.
- the above-mentioned “presence or absence of undeposition in pattern” indicates whether or not an undeposited portion of the copper plating layer is generated on the surface of the aluminum circuit pattern.
- the deposition rate of the electroless copper plating layer was determined by measurement with a fluorescent X-ray film thickness gauge.
- the plating appearance was visually evaluated (“ ⁇ ” for the uniform plating appearance and “X” for the uneven plating appearance). The results of these confirmations are shown in Table 3 as well.
- Example 2 the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 2, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “2 mg/L” in terms of concentration of tellurium. Accordingly, the description of the conditions for the electroless copper plating in Example 2 is omitted.
- Example 3 the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 3, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “10 mg/L” in terms of concentration of tellurium. Accordingly, the description of the conditions for the electroless copper plating in Example 3 is omitted.
- Example 4 the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 4, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “20 mg/L” in terms of concentration of tellurium. Accordingly, the description of the conditions for the electroless copper plating in Example 4 is omitted.
- Example 5 the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 5, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “50 mg/L” in terms of concentration of tellurium. Accordingly, the description of the conditions for the electroless copper plating in Example 5 is omitted.
- Example 6 the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 6, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “5 mg/L” in terms of concentration of tellurium and the solution pH was changed to 6.5. Accordingly, the description of the conditions for the electroless copper plating in Example 6 is omitted.
- Example 7 the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 7, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “5 mg/L” in terms of concentration of tellurium and the solution pH was changed to 7.0. Accordingly, the description of the conditions for the electroless copper plating in Example 7 is omitted.
- Example 8 the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 8, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “5 mg/L” in terms of concentration of tellurium and the solution pH was changed to 8.0. Accordingly, the description of the conditions for the electroless copper plating in Example 8 is omitted.
- Example 9 the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1.
- the results of this confirmation are shown in Table 3.
- the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “5 mg/L” in terms of concentration of tellurium and the solution pH was changed to 8.5. Accordingly, the description of the conditions for the electroless copper plating in Example 9 is omitted.
- Comparative Example 1 the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Comparative Example 1, the electroless copper plating was performed under the same conditions as in Example 1, except that “antimony oxide” was used in place of sodium tellurate as a deposition stabilizer in the electroless copper plating solution composition in order to compare with Examples 1 to 9, the content thereof was set at 4 mg/L in terms of concentration of antimony, and the concentration of the reducing agent was set at 0.14 mol/L. Accordingly, the description of the conditions for the electroless copper plating in Comparative Example 1 is omitted.
- Comparative Example 2 the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Comparative Example 2, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition, was changed to “0 mg/L (i.e., no sodium tellurate)” in terms of concentration of tellurium in order to compare with Examples 1 to 9. Accordingly, the description of the conditions for the electroless copper plating in Comparative Example 2 is omitted.
- Comparative Example 3 the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Comparative Example 3, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “200 mg/L” in terms of concentration of tellurium in order to compare with Examples 1 to 9. Accordingly, the description of the conditions for the electroless copper plating in Comparative Example 3 is omitted.
- compositions of the electroless copper plating solutions used in Examples and Comparative Examples are listed in Table 2.
- Examples 1 to 9 gave good results in all of “plating appearance”, “out-of-pattern deposition”, “undeposition of pattern”, and “solution stability”.
- Comparative Example 1 when antimony was contained instead of tellurium as a deposition stabilizer in the electroless copper plating solution, a decrease in solution stability was observed. Furthermore, in Comparative Example 1, the plating layer was not formed sufficiently on the surface of the aluminum circuit pattern on the substrate, nor was the plating appearance uniform.
- the concentration of tellurium in the deposition stabilizer was less than 0.5 mg/L, as in Comparative Example 2, deteriorated plating appearance and solution stability was also observed as. In Comparative Example 2, a protrusion from the pattern was further observed.
- the concentration of tellurium in the deposition stabilizer was more than 100 mg/L, as in Comparative Example 3, almost no plating was deposited, and thus the plating layer was not formed on the surface of the aluminum circuit pattern on the substrate.
- the electroless copper plating solution according to the present application is used in a neutral range and does not cause damage to an object to be plated. Therefore, the electroless copper plating solution is usable in the object to be plated such as an aluminum material or a ceramic material, which is easily damaged. In addition, since the electroless copper plating solution has a long life and excellent solution stability, the running cost of electroless copper plating can be reduced.
Abstract
Description
- The present application relates to an electroless copper plating solution, particularly to a reducing electroless copper plating solution used in a neutral range.
- Conventionally, an electroless copper plating solution has been employed that uses formaldehyde as a reducing agent for copper ions. However, formaldehyde has an irritating odor that deteriorates the working environment and causes adverse effects on the human body. Furthermore, the electroless copper plating solution using formaldehyde is strongly alkaline, and thus the use of the electroless copper plating solution is difficult especially when the object to be plated is aluminum, aluminum alloy, or the like.
- Therefore, it has been studied to use a borane compound in place of formaldehyde as a reducing agent. Due to the excessive reducing power, however, there have been problems such as the reductive deposition of metal on a wall surface or the like of a plating tank and the low stability of a plating solution due to the deposition of metal components over time.
- To solve such problems, an electroless copper plating solution as disclosed in Patent Literature 1 has been proposed. This Patent Literature 1 discloses “an electroless copper plating bath having a pH of 4 to 9, containing a water-soluble copper salt, amino borane or a substituted derivative thereof as a reducing agent, and no formaldehyde, the electroless copper plating bath containing polyaminopolyphosphonic acid as a complexing agent, an anionic surfactant, an antimony compound, and a nitrogen-containing aromatic compound”.
-
- Patent Literature 1: Japanese Patent Laid-Open No. 2013-234343
- However, the following problems have been pointed out in the electroless copper plating bath disclosed in Patent Literature 1: the first problem is that if the electroless copper plating bath disclosed in Patent Literature 1 is left in a plating bath for a long time after use, copper tends to deposit on the bottom of the bath, stirring jigs, and the like, resulting in a high tendency to have a lack of solution stability as a plating solution; the second problem is that an electroless copper plating layer formed using the electroless copper plating bath disclosed in Patent Literature 1 tends to have a non-uniform appearance; and the third problem is that when plating is performed on an aluminum material using the electroless copper plating bath disclosed in Patent Literature 1, the copper plating layer tends to swell even if the aluminum itself is not damaged, resulting in a tendency for pits to occur.
- Although the above problems have been pointed out in the market, in the use of the electroless copper plating bath disclosed in Patent Literature 1, the control range of proper composition is narrow, and solution stability is poor, which probably makes it difficult to achieve operational stability in plating.
- Accordingly, an object of the present application is to provide an electroless copper plating solution with excellent solution stability and easy composition control, which does not cause the above-mentioned problems.
- As a result of intensive studies, the inventors of the present application have conceived of employing the following formaldehyde-free electroless copper plating solution. The summary of the invention of the electroless copper plating solution according to the present application will be described below.
- The electroless copper plating solution according to the present application is a reducing electroless copper plating solution used in a neutral range that contains a copper salt serving as a copper ion supply source, a complexing agent for chelating copper ions, a reducing agent, a surfactant, an aromatic compound containing nitrogen, and contains a tellurium compound serving as a deposition stabilizer, and that has a solution pH of 6 to 9.
- In the electroless copper plating solution according to the present application, the tellurium compound serving as a deposition stabilizer is preferably used in a concentration range of 0.1 mg/L to 100 mg/L in terms of tellurium.
- In the electroless copper plating solution according to the present application, the complexing agent for chelating copper ions is preferably a phosphonic acid-based chelating agent is used in a concentration range of 0.1 to 10 times the number of moles of copper.
- In the electroless copper plating solution according to the present application, the reducing agent is preferably amine borane or a derivative thereof.
- In the electroless copper plating solution according to the present application, the surfactant is preferably an anionic surfactant used in a concentration range of 0.01 mg/L to 1500 mg/L.
- In the electroless copper plating solution according to the present application, the aromatic compound containing nitrogen is preferably used in a concentration range of 0.01 mg/L to 1000 mg/L.
- The electroless copper plating solution according to the present application contains a tellurium compound serving as a deposition stabilizer for the electroless copper plating solution, thereby dramatically improving the solution stability as a plating solution even though it is used in a neutral range without containing formaldehyde. As a result, a change in the composition of the plating solution during plating operation is small, a stable copper plating layer can be formed even if the composition is slightly changed, and it becomes possible to obtain layer thickness uniformity and uniform appearance quality of the copper plating layer. Then, even if the electroless copper plating solution is left in the plating tank after the plating operation, unnecessary copper deposition does not occur while a plating solution is less deteriorated, making it possible to prolong the life of the solution. Furthermore, by employing the electroless copper plating solution in the neutral range according to the present application, aluminum itself is not damaged when the solution is plated on an aluminum material, and plating defects such as blisters and pits in the plating layer can be efficiently eliminated.
- Embodiments of the electroless copper plating solution according to the present application and electroless copper plating methods using the same will be described below.
- A. Embodiments of Electroless Copper Plating Solution
- The electroless copper plating solution according to the present application is an electroless copper plating solution used in a neutral range, and this electroless copper plating solution contains a tellurium compound serving as a deposition stabilizer in terms of a component and has a solution pH of 6 to 9. The solution pH of the electroless copper plating solution will be described below, and then each component will be described.
- Solution pH: The solution pH is preferably 6.0 to 9.0. When the solution pH is less than 6.0, the electroless copper plating solution is in an acidic range, which is not preferable because the effect of components such as the reducing agents described below is likely to decrease, making it difficult to prolong the life of the electroless copper plating solution. On the other hand, when the solution pH is more than 9.0, the electroless copper plating solution is in an alkaline range, which is not preferable because the surface of the object to be plated, such as an aluminum material or a ceramic material, is more likely to be damaged. Here, the solution pH is more preferably 6.5 to 8.5, which is even closer to neutral, and in this case, the damage to the object to be plated can be prevented more reliably.
- As a pH adjusting agent when the solution pH of the electroless copper plating solution according to the present application needs to be adjusted, hydrochloric acid, sulfuric acid, or the like may be used to adjust the solution pH to the acid side while sodium hydroxide, potassium hydroxide, or the like may be used to adjust the solution pH to the alkali side.
- Deposition stabilizer: In the electroless copper plating solution according to the present application, the tellurium compound serving as a deposition stabilizer is used. Examples of the tellurium compound include any one or more of telluric acid and a salt thereof, tellurous acid and a salt thereof, tellurium dioxide, tellurium trioxide, tellurium chloride, and dimethyl telluride. By using these tellurium compounds, all of the problems that have not been solved in the past can now be solved. In other words, the solution stability is dramatically improved by using a tellurium compound serving as a deposition stabilizer in the electroless copper plating solution, and thus the plating solution can be easily managed. At the same time, the deposition state during the formation of a copper plating layer is also stable, making it possible to form a good copper plating layer.
- The tellurium compound serving as a deposition stabilizer is preferably contained in the electroless copper plating solution in a concentration range of 0.1 mg/L to 100 mg/L in terms of tellurium. When the content of the tellurium compound is less than 0.1 mg/L in terms of concentration of tellurium, the solution stability of the electroless copper plating solution cannot be improved, the lifetime extension of the plating solution cannot be achieved, and the characteristics of the plating solution vary due to the change in the composition, making it difficult to use the electroless copper plating solution for a long time, which is not preferable. On the other hand, when the content of the tellurium compound is more than 100 mg/L in concentration as tellurium, the phenomenon that copper deposition is markedly reduced is observed, which is not preferable because rapid copper plating layer formation becomes difficult. From the viewpoint of reliably ensuring the stability of the copper deposition rate, therefore, the content of the tellurium compound is more preferably in the concentration range of 0.3 mg/L to 70 mg/L in terms of concentration of tellurium. In order to ensure the effect of the addition of the tellurium compound, and minimize the variation in the formation rate of the copper plating layer, the tellurium compound is most preferably contained in the concentration range of 0.5 mg/L to 50 mg/L in terms of tellurium.
- Copper ion supply source: The copper salt serving as a copper ion supply source is used in the electroless copper plating solution according to the present application. Examples of the copper salt include any one or more of water-soluble copper salts such as copper sulfate, copper nitrate, copper chloride, copper acetate, copper citrate, copper tartrate, copper gluconate, and hydrates thereof. As described above, two or more copper salts of the present application can be simultaneously used in combination, and there is no particular limitation on the mixing ratio of two or more copper salts as long as the amount of copper ions is in the following range. Considering the conditions such as raw material cost and wastewater load, it is preferable that the most widely available is copper sulfate (copper sulfate pentahydrate) or a combination of copper sulfate and copper hydrochloride.
- In the electroless copper plating solution according to the present application, the content of the copper salt is preferably in the concentration range of 0.01 mol/L to 1 mol/L in terms of concentration of copper. When the content of the copper salt in the electroless copper plating solution according to the present application is less than 0.01 mol/L in terms of concentration of copper because the copper deposition rate is remarkably decreased, the time required for operation becomes long, and the productivity required for industrial purposes cannot be obtained, which is not preferable. On the other hand, even if the content of copper salt is more than 1 mol/L in terms of concentration of copper, the copper deposition rate is not improved, but rather the appearance defects of the formed copper plating layer tend to increase, which is not preferable. From the viewpoint of reliably ensuring the appearance quality of the copper plating layer to be formed, therefore, the content of the copper salt is preferably in the concentration range of 0.02 mol/L to 0.5 mol/L in terms of concentration of copper.
- Complexing agent: The electroless copper plating solution according to the present application is used in the neutral range, and it is preferable to use a phosphonic acid-based chelating agent as the complexing agent. This is because the phosphonic acid-based chelating agent easily forms a complex of copper ions in the neutral range. The phosphonic acid-based chelating agent includes 1-hydroxyethane-1,1-diphosphonic acid, N,N,N′,N′-ethylenediaminetetrakis(methylenephosphonic acid), nitrilotris(methylenephosphonic acid), diethylenediaminepenta(methylenephosphonic acid), diethylenetriaminepenta(methylenephosphonic acid), bis(hexamethylenetriaminepenta(methylenephosphonic acid)), glycine-N,N-bis(methylenephosphonic acid), and salts thereof, and one or more of them can be used simultaneously.
- Since the complexing agent chelates copper ions, the amount of the complexing agent added is determined by the copper content in the electroless copper plating solution. In the electroless copper plating solution according to the present application, the phosphonic acid-based chelating agent as a complexing agent is preferably used in a concentration range of 0.1 to 10 times the number of moles of copper in the electroless copper plating solution. When the concentration of the phosphonic acid-based chelating agent is less than 0.1 times the number of moles of copper, copper ions cannot be sufficiently complexed, and solution stability as an electroless copper plating solution cannot be ensured, which is not preferable. On the other hand, when the concentration of the phosphonic acid-based chelating agent is more than 10 times the number of moles of copper, the amount of the chelating agent is more than the amount required for the complexation of copper ions, which is not preferable because it wastes resources and also causes the appearance quality of the copper plating layer to deteriorate.
- Reducing agent: Various reducing agents can be used for copper ions. In the case of the electroless copper plating solution according to the present application, however, since it is used in the neutral range, it is preferable to use amine borane or a derivative thereof as a reducing agent usable in the neutral range in order to ensure the solution stability. More specifically, any one or more of dimethylamine borane, diethylamine borane, tert-butylamine borane, triethylamine borane, trimethylamine borane, and the like can be used. The concentration of this reducing agent is not particularly limited, but it is reasonable to set the concentration in the range of 0.01 mol/L to 0.5 mol/L. When the concentration of the reducing agent is less than 0.01 mol/L, the copper deposition rate is slow, which is not preferable. On the other hand, when the concentration of the reducing agent is more than 0.5 mol/L, it is not preferable because the copper deposition rate does not increase and is simply a waste of resources.
- Surfactant: In the electroless copper plating solution according to the present application, it is preferable to use a surfactant for the purpose of improving the solution stability and improving the layer thickness uniformity and appearance quality of the plating layer to be formed. Especially in the case of an electroless copper plating solution used in the neutral range, it is preferable to use an anionic surfactant.
- As the anionic surfactants, all the surfactants which are called “anionic surfactants” or “anionic surface-active agents” in the market can be used. Examples include any one or more of alkylcarboxylic acid-based surfactants, naphthalene sulfonate formaldehyde condensates such as sodium salts of β-naphthalene sulfonate formalin condensate, polyoxyalkylene ether sulfates such as sodium polyoxyethylene lauryl ether sulfate and triethanolamine polyoxyethylene alkyl ether sulfate, and sodium dodecyl sulfate, but not special limitations are required.
- The concentration of the surfactant is not particularly limited, but it is reasonable to set the concentration in the range of 0.01 mg/L to 1500 mg/L. When the concentration of the surfactant is less than 0.01 mg/L, it is not preferable since the solution stability of the electroless copper plating solution does not improve, making it difficult to prolong the life of the plating solution, and the appearance quality of the copper plating layer tends to deteriorate. On the other hand, when the concentration of the surfactant is more than 1500 mg/L, there is no particular problem, but the solution stability is not further improved nor the appearance quality is improved. Besides, the bath control during the plating operation becomes complicated, which is not preferable.
- Aromatic compound containing nitrogen: In the electroless copper plating solution according to the present application, an aromatic compound containing nitrogen (so-called a heterocyclic aromatic compound containing nitrogen) is used to stabilize copper deposition in electroless copper plating. Examples of the nitrogen-containing aromatic compounds include any one or more of: imidazole or substituted derivatives thereof; pyrazole or substituted derivatives thereof; oxazole or substituted derivatives thereof; thiazole or substituted derivatives thereof; pyrazine or substituted derivatives thereof; pyridazine or substituted derivatives thereof; triazine or substituted derivatives thereof; benzothiazole or substituted derivatives thereof; pyridines such as pyridine, 2,2′-dipyridyl, 4,4′-dipyridyl, nicotinic acid, nicotinamide, picolines, and lutidines, or substituted derivatives thereof; quinolines such as quinoline and hydroxyquinoline, or substituted derivatives thereof; acridines such as acridine, 3,6-dimethylaminoacridine, proflavine, acridine acid, and quinoline-1,2-dicarboxylic acid, or substituted derivatives thereof; pyrimidines such as pyrimidine, uracil, uridine, thymine, 2-thiouracil, 6-methyl-2-thiouracil, and 6-propyl-2-thiouracil, or substituted derivatives thereof; and phenanthrolines such as 1,10-phenanthroline, neocuproine, and bathophenanthroline, or substituted derivatives thereof; and purines such as purine, aminopurine, adenine, adenosine, guanine, hydantoin, xanthine, hypoxanthine, caffeine, theophylline, theobromine, and aminophylline, or substituted derivative thereof.
- The concentration of the aromatic compound containing nitrogen that is contained in the electroless copper plating solution according to the present application is preferably 0.01 mg/L to 1000 mg/L. When the concentration of the aromatic compound containing nitrogen is less than 0.01 mg/L, the effect as a deposition stabilizer for copper cannot be exhibited, which is not preferable because the appearance of the formed copper plating layer is also impaired. On the other hand, when the concentration of the aromatic compound containing nitrogen is more than 1000 mg/L, the solution stability of the electroless copper plating solution becomes excessive, which is not preferable because it causes a decrease in the copper deposition rate and an undeposited portion of the plating layer is generated.
- B. Electroless Copper Plating Method
- Regarding the electroless copper plating method, conventionally known electroless plating methods and conditions may be applied using the above-mentioned electroless copper plating solution. Therefore, it is considered unnecessary to describe the electroless copper plating method in detail here, and the electroless plating methods and conditions are described in Example.
- Although the electroless copper plating solution according to the present application has been described above, the present application will be described in more detail below with reference to Examples and Comparative Examples of the present application. Note that the present application is not limited to these examples at all.
- In Example 1, the solution stability as a plating solution was confirmed after electroless copper plating was performed using an electroless copper plating solution containing a copper salt serving as a copper ion supply source, a complexing agent for chelating copper ions, a reducing agent, a surfactant, an aromatic compound containing nitrogen, and containing a tellurium compound serving as a deposition stabilizer, and having a solution pH of 7.7 and a solution temperature of 60° C. Here, the evaluation of the solution stability as a plating solution is indicated by “◯” when no deposition was observed on a part other than the object to be treated, by “Δ” when the deposition was slightly observed, and by “X” when the deposition was remarkably or decomposition of the plating solution occurred during plating, after the electroless copper plating solution is heated and plated while keeping the solution temperature constant, and then the electroless copper plating solution is left for 12 hours. The results of this confirmation are shown in Table 3 below.
- In Example 1, a substrate with an aluminum circuit (hereinafter simply referred to as a substrate), an object to be plated, was subjected to pretreatment under the conditions listed in Table 1 below (in the order from the top in the table), and then immersed in an electroless copper plating solution for 120 minutes to perform electroless copper plating, thereby forming a copper plating layer on the surface of the aluminum circuit pattern.
-
TABLE 1 Treatment Treatment step Name of bath condition Degreasing Melcleaner SC-7001 70° C., 30 secs Etching Melplate E-7121 70° C., 30 secs Conditioning Melplate Conditioner 7230 22° C., 20 secs Single zincate treatment Melplate FZ-7350 22° C., 20 secs Zinc stripping 20 wt % nitric acid 22° C., 10 secs Double zincate treatmen Melplate FBZ 22° C., 30 secs - In Example 1, an electroless copper plating solution having the composition shown below was prepared.
-
-
- Copper salt (copper sulfate pentahydrate): 0.06 mol/L (4 g/L in terms of concentration of copper)
- Complexing Agent
-
- (ethylenediaminetetra(methylenephosphonic acid)): 0.08 mol/L
- Reducing agent (dimethylamine borane): 0.09 mol/L
- Surfactant (sodium dodecyl sulfate): 20 mg/L
- Aromatic compound containing nitrogen (1,10-phenanthroline): 4 mg/L
- Deposition stabilizer (sodium tellurate): 1 mg/L (in terms of concentration of tellurium)
- In Example 1, the deposition rate of the electroless copper plating layer, the plating appearance, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the copper plating layer after the plating layer was formed on the surface of the aluminum circuit pattern (hereinafter, also simply referred to as a pattern) on the substrate were confirmed. Note that the above-mentioned “presence or absence of undeposition in pattern” indicates whether or not an undeposited portion of the copper plating layer is generated on the surface of the aluminum circuit pattern. Here, the deposition rate of the electroless copper plating layer was determined by measurement with a fluorescent X-ray film thickness gauge. In addition, the plating appearance was visually evaluated (“◯” for the uniform plating appearance and “X” for the uneven plating appearance). The results of these confirmations are shown in Table 3 as well.
- In Example 2, the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 2, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “2 mg/L” in terms of concentration of tellurium. Accordingly, the description of the conditions for the electroless copper plating in Example 2 is omitted.
- In Example 3, the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 3, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “10 mg/L” in terms of concentration of tellurium. Accordingly, the description of the conditions for the electroless copper plating in Example 3 is omitted.
- In Example 4, the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 4, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “20 mg/L” in terms of concentration of tellurium. Accordingly, the description of the conditions for the electroless copper plating in Example 4 is omitted.
- In Example 5, the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 5, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “50 mg/L” in terms of concentration of tellurium. Accordingly, the description of the conditions for the electroless copper plating in Example 5 is omitted.
- In Example 6, the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 6, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “5 mg/L” in terms of concentration of tellurium and the solution pH was changed to 6.5. Accordingly, the description of the conditions for the electroless copper plating in Example 6 is omitted.
- In Example 7, the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 7, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “5 mg/L” in terms of concentration of tellurium and the solution pH was changed to 7.0. Accordingly, the description of the conditions for the electroless copper plating in Example 7 is omitted.
- In Example 8, the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 8, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “5 mg/L” in terms of concentration of tellurium and the solution pH was changed to 8.0. Accordingly, the description of the conditions for the electroless copper plating in Example 8 is omitted.
- In Example 9, the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Example 9, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “5 mg/L” in terms of concentration of tellurium and the solution pH was changed to 8.5. Accordingly, the description of the conditions for the electroless copper plating in Example 9 is omitted.
- In Comparative Example 1, the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Comparative Example 1, the electroless copper plating was performed under the same conditions as in Example 1, except that “antimony oxide” was used in place of sodium tellurate as a deposition stabilizer in the electroless copper plating solution composition in order to compare with Examples 1 to 9, the content thereof was set at 4 mg/L in terms of concentration of antimony, and the concentration of the reducing agent was set at 0.14 mol/L. Accordingly, the description of the conditions for the electroless copper plating in Comparative Example 1 is omitted.
- In Comparative Example 2, the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Comparative Example 2, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition, was changed to “0 mg/L (i.e., no sodium tellurate)” in terms of concentration of tellurium in order to compare with Examples 1 to 9. Accordingly, the description of the conditions for the electroless copper plating in Comparative Example 2 is omitted.
- In Comparative Example 3, the solution stability of the plating solution, the deposition rate of the electroless copper plating layer, and the presence or absence of out-of-pattern deposition and undeposition in pattern of the plating layer were confirmed as in Example 1. The results of this confirmation are shown in Table 3. Note that in Comparative Example 3, the electroless copper plating was performed under the same conditions as in Example 1, except that the content of sodium tellurate, a deposition stabilizer, in the electroless copper plating solution composition was changed to “200 mg/L” in terms of concentration of tellurium in order to compare with Examples 1 to 9. Accordingly, the description of the conditions for the electroless copper plating in Comparative Example 3 is omitted.
- Here, for ease of understanding, the compositions of the electroless copper plating solutions used in Examples and Comparative Examples are listed in Table 2.
-
TABLE 2 Composition and conditions Aromatic compound Copper Complexing Reducing containing Deposition Solution salt agent agent Surfactant nitrogen stabilizer Solution temperature Sample (mol/L) (mol/L) (mol/L) (mg/L) (mg/L) (mg/L) pH (° C.) Example 1 0.06 0.08 0.09 20 4 1 7.7 60 2 0.06 0.08 0.09 20 4 2 7.7 60 3 0.06 0.08 0.09 20 4 10 7.7 60 4 0.06 0.08 0.09 20 4 20 7.7 60 5 0.06 0.08 0.09 20 4 50 7.7 60 6 0.06 0.08 0.09 20 4 5 6.5 60 7 0.06 0.08 0.09 20 4 5 7.0 60 8 0.06 0.08 0.09 20 4 5 8.0 60 9 0.06 0.08 0.09 20 4 5 8.5 60 Comparative 1 0.06 0.08 0.14 20 4 4 * 7.7 60 Example 2 0.06 0.08 0.09 20 4 0 7.7 60 3 0.06 0.08 0.09 20 4 200 7.7 60 * Use of “antimony oxide” as a deposition stabilizer (with a content of 4 mg/L in terms of concentration of antimony) - The confirmation results of the tests conducted as Examples and Comparative Examples are shown in Table 3.
-
TABLE 3 Confirmation results Depo- Out-of- sition Plating pattern Undepo- rate appear- depo- sition in Solution Sample (μm/h) ance sition pattern stability Example 1 3.9 ◯ Absent Absent ◯ 2 4.3 ◯ Absent Absent ◯ 3 5.4 ◯ Absent Absent ◯ 4 5.2 ◯ Absent Absent ◯ 5 4.3 ◯ Absent Absent ◯ 6 1.0 ◯ Absent Absent ◯ 7 2.6 ◯ Absent Absent ◯ 8 10.0 ◯ Absent Absent ◯ 9 10.7 ◯ Absent Absent ◯ Compar- 1 6.1 X Absent Present X ative 2 2.0 X Present Absent Δ Example 3 Undepo- — — — ◯ sited - (Results and Evaluation)
- From the confirmation results shown in Table 3, Examples 1 to 9 gave good results in all of “plating appearance”, “out-of-pattern deposition”, “undeposition of pattern”, and “solution stability”. On the other hand, as in Comparative Example 1, when antimony was contained instead of tellurium as a deposition stabilizer in the electroless copper plating solution, a decrease in solution stability was observed. Furthermore, in Comparative Example 1, the plating layer was not formed sufficiently on the surface of the aluminum circuit pattern on the substrate, nor was the plating appearance uniform. When the concentration of tellurium in the deposition stabilizer was less than 0.5 mg/L, as in Comparative Example 2, deteriorated plating appearance and solution stability was also observed as. In Comparative Example 2, a protrusion from the pattern was further observed. When the concentration of tellurium in the deposition stabilizer was more than 100 mg/L, as in Comparative Example 3, almost no plating was deposited, and thus the plating layer was not formed on the surface of the aluminum circuit pattern on the substrate.
- Based on the above, it was found that a change in the composition of the plating solution during plating operation is small and a stable copper plating layer can be formed even if the solution is a reducing electroless copper plating solution used in the neutral range without containing formaldehyde by satisfying the conditions of the present application, “containing a copper salt serving as a copper ion supply source, a complexing agent for chelating copper ions, a reducing agent, a surfactant, an aromatic compound containing nitrogen, and containing a tellurium compound serving as a deposition stabilizer, and having a solution pH of 6 to 9”.
- The electroless copper plating solution according to the present application is used in a neutral range and does not cause damage to an object to be plated. Therefore, the electroless copper plating solution is usable in the object to be plated such as an aluminum material or a ceramic material, which is easily damaged. In addition, since the electroless copper plating solution has a long life and excellent solution stability, the running cost of electroless copper plating can be reduced.
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Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007092111A (en) * | 2005-09-28 | 2007-04-12 | Okuno Chem Ind Co Ltd | Composition for preventing plating deposition |
JP2013234343A (en) * | 2012-05-07 | 2013-11-21 | C Uyemura & Co Ltd | Electroless copper plating bath and electroless copper plating method |
JP2013234434A (en) * | 2012-05-07 | 2013-11-21 | Kajima Corp | Base isolation device support unit for inverted construction method and construction method of base isolation structure using the same |
KR101660520B1 (en) * | 2015-04-08 | 2016-09-29 | 한국생산기술연구원 | Method of performing continuous electroless plating of copper and nickel and plating layer using the same |
US20170051411A1 (en) * | 2015-08-20 | 2017-02-23 | Macdermid Acumen, Inc. | Electroless Silver Plating Bath and Method of Using the Same |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2721567A1 (en) * | 1977-05-13 | 1978-11-16 | Cannings Ltd W | Tellerium-stabilised electroless copper plating soln. - by addition of tellurous or telluric acid or salt |
JPS53142328A (en) * | 1977-05-17 | 1978-12-12 | Canning & Co Ltd W | Solution for nonnelectrolytic copper plating |
JP3227504B2 (en) * | 1993-04-19 | 2001-11-12 | 奥野製薬工業株式会社 | Electroless copper plating solution |
EP2034049A1 (en) * | 2007-09-05 | 2009-03-11 | Nederlandse Organisatie voor toegepast- natuurwetenschappelijk onderzoek TNO | An electroless process for depositing a metal on a non-catalytic substrate |
EP2784181B1 (en) * | 2013-03-27 | 2015-12-09 | ATOTECH Deutschland GmbH | Electroless copper plating solution |
WO2016097083A2 (en) * | 2014-12-17 | 2016-06-23 | Atotech Deutschland Gmbh | Plating bath composition and method for electroless plating of palladium |
-
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Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007092111A (en) * | 2005-09-28 | 2007-04-12 | Okuno Chem Ind Co Ltd | Composition for preventing plating deposition |
JP2013234343A (en) * | 2012-05-07 | 2013-11-21 | C Uyemura & Co Ltd | Electroless copper plating bath and electroless copper plating method |
JP2013234434A (en) * | 2012-05-07 | 2013-11-21 | Kajima Corp | Base isolation device support unit for inverted construction method and construction method of base isolation structure using the same |
KR101660520B1 (en) * | 2015-04-08 | 2016-09-29 | 한국생산기술연구원 | Method of performing continuous electroless plating of copper and nickel and plating layer using the same |
US20170051411A1 (en) * | 2015-08-20 | 2017-02-23 | Macdermid Acumen, Inc. | Electroless Silver Plating Bath and Method of Using the Same |
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DE112021005992T5 (en) | 2023-08-24 |
CN116194618A (en) | 2023-05-30 |
TW202219320A (en) | 2022-05-16 |
KR20230011434A (en) | 2023-01-20 |
JPWO2022102226A1 (en) | 2022-05-19 |
JP7111410B1 (en) | 2022-08-02 |
KR102587691B1 (en) | 2023-10-10 |
WO2022102226A1 (en) | 2022-05-19 |
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