GB2494576A - A method of producing granulated ITO powder - Google Patents
A method of producing granulated ITO powder Download PDFInfo
- Publication number
- GB2494576A GB2494576A GB1222458.0A GB201222458A GB2494576A GB 2494576 A GB2494576 A GB 2494576A GB 201222458 A GB201222458 A GB 201222458A GB 2494576 A GB2494576 A GB 2494576A
- Authority
- GB
- United Kingdom
- Prior art keywords
- text
- slurry
- mould
- ito
- precipitate
- 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.)
- Granted
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- 238000000034 method Methods 0.000 title claims abstract description 75
- 239000000843 powder Substances 0.000 title claims abstract description 29
- 239000002002 slurry Substances 0.000 claims abstract description 38
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims abstract description 20
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 claims abstract description 16
- 238000004519 manufacturing process Methods 0.000 claims abstract description 15
- 239000002244 precipitate Substances 0.000 claims abstract description 15
- 229910003437 indium oxide Inorganic materials 0.000 claims abstract description 14
- 239000011872 intimate mixture Substances 0.000 claims abstract description 14
- 229910001887 tin oxide Inorganic materials 0.000 claims abstract description 14
- -1 phosphorus compound Chemical class 0.000 claims abstract description 13
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims abstract description 12
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 11
- 239000011574 phosphorus Substances 0.000 claims abstract description 11
- 238000005477 sputtering target Methods 0.000 claims abstract description 9
- 238000005406 washing Methods 0.000 claims abstract description 8
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims abstract description 6
- 238000001914 filtration Methods 0.000 claims abstract description 6
- PJXISJQVUVHSOJ-UHFFFAOYSA-N indium(iii) oxide Chemical compound [O-2].[O-2].[O-2].[In+3].[In+3] PJXISJQVUVHSOJ-UHFFFAOYSA-N 0.000 claims abstract description 6
- QUBMWJKTLKIJNN-UHFFFAOYSA-B tin(4+);tetraphosphate Chemical compound [Sn+4].[Sn+4].[Sn+4].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O QUBMWJKTLKIJNN-UHFFFAOYSA-B 0.000 claims abstract description 5
- 230000001376 precipitating effect Effects 0.000 claims abstract description 4
- UJXZVRRCKFUQKG-UHFFFAOYSA-K indium(3+);phosphate Chemical compound [In+3].[O-]P([O-])([O-])=O UJXZVRRCKFUQKG-UHFFFAOYSA-K 0.000 claims abstract description 3
- HPGGPRDJHPYFRM-UHFFFAOYSA-J tin(iv) chloride Chemical compound Cl[Sn](Cl)(Cl)Cl HPGGPRDJHPYFRM-UHFFFAOYSA-J 0.000 claims abstract 5
- 229910021627 Tin(IV) chloride Inorganic materials 0.000 claims abstract 4
- YWEUIGNSBFLMFL-UHFFFAOYSA-N diphosphonate Chemical compound O=P(=O)OP(=O)=O YWEUIGNSBFLMFL-UHFFFAOYSA-N 0.000 claims abstract 3
- DLYUQMMRRRQYAE-UHFFFAOYSA-N phosphorus pentoxide Inorganic materials O1P(O2)(=O)OP3(=O)OP1(=O)OP2(=O)O3 DLYUQMMRRRQYAE-UHFFFAOYSA-N 0.000 claims abstract 3
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 claims description 18
- 239000002738 chelating agent Substances 0.000 claims description 10
- DEFVIWRASFVYLL-UHFFFAOYSA-N ethylene glycol bis(2-aminoethyl)tetraacetic acid Chemical compound OC(=O)CN(CC(O)=O)CCOCCOCCN(CC(O)=O)CC(O)=O DEFVIWRASFVYLL-UHFFFAOYSA-N 0.000 claims description 10
- FTEDXVNDVHYDQW-UHFFFAOYSA-N BAPTA Chemical compound OC(=O)CN(CC(O)=O)C1=CC=CC=C1OCCOC1=CC=CC=C1N(CC(O)=O)CC(O)=O FTEDXVNDVHYDQW-UHFFFAOYSA-N 0.000 claims description 9
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 claims description 9
- 239000011230 binding agent Substances 0.000 claims description 9
- 229910052738 indium Inorganic materials 0.000 claims description 9
- 239000000203 mixture Substances 0.000 claims description 8
- 238000007789 sealing Methods 0.000 claims description 8
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 7
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Inorganic materials [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 claims description 7
- ZOMBKNNSYQHRCA-UHFFFAOYSA-J calcium sulfate hemihydrate Chemical compound O.[Ca+2].[Ca+2].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O ZOMBKNNSYQHRCA-UHFFFAOYSA-J 0.000 claims description 7
- 150000001875 compounds Chemical class 0.000 claims description 7
- 239000002270 dispersing agent Substances 0.000 claims description 7
- 239000011507 gypsum plaster Substances 0.000 claims description 7
- 229910052760 oxygen Inorganic materials 0.000 claims description 7
- 239000001301 oxygen Substances 0.000 claims description 7
- CZMRCDWAGMRECN-UGDNZRGBSA-N Sucrose Chemical compound O[C@H]1[C@H](O)[C@@H](CO)O[C@@]1(CO)O[C@@H]1[C@H](O)[C@@H](O)[C@H](O)[C@@H](CO)O1 CZMRCDWAGMRECN-UGDNZRGBSA-N 0.000 claims description 6
- 229930006000 Sucrose Natural products 0.000 claims description 6
- 239000010440 gypsum Substances 0.000 claims description 6
- 229910052602 gypsum Inorganic materials 0.000 claims description 6
- BHEPBYXIRTUNPN-UHFFFAOYSA-N hydridophosphorus(.) (triplet) Chemical compound [PH] BHEPBYXIRTUNPN-UHFFFAOYSA-N 0.000 claims description 6
- 239000005720 sucrose Substances 0.000 claims description 6
- 238000010304 firing Methods 0.000 claims description 5
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 claims description 4
- 239000008103 glucose Substances 0.000 claims description 4
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 claims description 3
- 238000005507 spraying Methods 0.000 claims description 3
- 229910019142 PO4 Inorganic materials 0.000 claims description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 claims description 2
- 239000010452 phosphate Substances 0.000 claims description 2
- 239000011248 coating agent Substances 0.000 claims 4
- 238000000576 coating method Methods 0.000 claims 4
- AMGQUBHHOARCQH-UHFFFAOYSA-N indium;oxotin Chemical compound [In].[Sn]=O AMGQUBHHOARCQH-UHFFFAOYSA-N 0.000 abstract description 2
- 229910001392 phosphorus oxide Inorganic materials 0.000 abstract description 2
- VSAISIQCTGDGPU-UHFFFAOYSA-N tetraphosphorus hexaoxide Chemical compound O1P(O2)OP3OP1OP2O3 VSAISIQCTGDGPU-UHFFFAOYSA-N 0.000 abstract description 2
- PSCMQHVBLHHWTO-UHFFFAOYSA-K indium(iii) chloride Chemical compound Cl[In](Cl)Cl PSCMQHVBLHHWTO-UHFFFAOYSA-K 0.000 abstract 5
- 238000004544 sputter deposition Methods 0.000 description 18
- 239000010409 thin film Substances 0.000 description 11
- 206010054107 Nodule Diseases 0.000 description 8
- 239000000463 material Substances 0.000 description 8
- 238000007569 slipcasting Methods 0.000 description 8
- 239000000243 solution Substances 0.000 description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 238000005336 cracking Methods 0.000 description 6
- QHGNHLZPVBIIPX-UHFFFAOYSA-N tin(ii) oxide Chemical class [Sn]=O QHGNHLZPVBIIPX-UHFFFAOYSA-N 0.000 description 6
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 5
- 230000002159 abnormal effect Effects 0.000 description 5
- 239000000460 chlorine Substances 0.000 description 5
- 229910052801 chlorine Inorganic materials 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 238000005245 sintering Methods 0.000 description 5
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 4
- 239000002253 acid Substances 0.000 description 4
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 4
- 150000001805 chlorine compounds Chemical class 0.000 description 4
- 239000000839 emulsion Substances 0.000 description 4
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 4
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 3
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 3
- 230000002411 adverse Effects 0.000 description 3
- 239000011575 calcium Substances 0.000 description 3
- 229910052791 calcium Inorganic materials 0.000 description 3
- 231100001261 hazardous Toxicity 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- 230000024121 nodulation Effects 0.000 description 3
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 2
- KZBUYRJDOAKODT-UHFFFAOYSA-N Chlorine Chemical compound ClCl KZBUYRJDOAKODT-UHFFFAOYSA-N 0.000 description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000000975 co-precipitation Methods 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 239000004677 Nylon Substances 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 238000005411 Van der Waals force Methods 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 235000019270 ammonium chloride Nutrition 0.000 description 1
- QZPSXPBJTPJTSZ-UHFFFAOYSA-N aqua regia Chemical compound Cl.O[N+]([O-])=O QZPSXPBJTPJTSZ-UHFFFAOYSA-N 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 229910052785 arsenic Inorganic materials 0.000 description 1
- 239000011324 bead Substances 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 229910001424 calcium ion Inorganic materials 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000009694 cold isostatic pressing Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical class 0.000 description 1
- 239000000383 hazardous chemical Substances 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 229910000039 hydrogen halide Inorganic materials 0.000 description 1
- 239000012433 hydrogen halide Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229920001778 nylon Polymers 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 238000002294 plasma sputter deposition Methods 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 230000007096 poisonous effect Effects 0.000 description 1
- 229920000058 polyacrylate Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000009747 press moulding Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000035755 proliferation Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 238000001771 vacuum deposition Methods 0.000 description 1
- RUDFQVOCFDJEEF-UHFFFAOYSA-N yttrium(III) oxide Inorganic materials [O-2].[O-2].[O-2].[Y+3].[Y+3] RUDFQVOCFDJEEF-UHFFFAOYSA-N 0.000 description 1
Classifications
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G19/00—Compounds of tin
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G15/00—Compounds of gallium, indium or thallium
-
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- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G19/00—Compounds of tin
- C01G19/02—Oxides
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- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/453—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zinc, tin, or bismuth oxides or solid solutions thereof with other oxides, e.g. zincates, stannates or bismuthates
- C04B35/457—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zinc, tin, or bismuth oxides or solid solutions thereof with other oxides, e.g. zincates, stannates or bismuthates based on tin oxides or stannates
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/62605—Treating the starting powders individually or as mixtures
- C04B35/6261—Milling
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/62605—Treating the starting powders individually or as mixtures
- C04B35/62645—Thermal treatment of powders or mixtures thereof other than sintering
- C04B35/62655—Drying, e.g. freeze-drying, spray-drying, microwave or supercritical drying
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/62605—Treating the starting powders individually or as mixtures
- C04B35/62645—Thermal treatment of powders or mixtures thereof other than sintering
- C04B35/62675—Thermal treatment of powders or mixtures thereof other than sintering characterised by the treatment temperature
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/62605—Treating the starting powders individually or as mixtures
- C04B35/62695—Granulation or pelletising
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- C—CHEMISTRY; METALLURGY
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
- C04B35/632—Organic additives
- C04B35/634—Polymers
- C04B35/63404—Polymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
- C04B35/63424—Polyacrylates; Polymethacrylates
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/64—Burning or sintering processes
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
- C23C14/34—Sputtering
- C23C14/3407—Cathode assembly for sputtering apparatus, e.g. Target
- C23C14/3414—Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
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- C01P2006/12—Surface area
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3286—Gallium oxides, gallates, indium oxides, indates, thallium oxides, thallates or oxide forming salts thereof, e.g. zinc gallate
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Abstract
A method of producing granulated ITO (indium tin oxide) powder for use in the manufacture of ITO sputtering targets comprises: burning in air (preferably at 800-1200°C) an intimate mixture of ITO powder and chloride ions present as InCl3 (indium chloride) and SnCl4 (tin chloride), wherein the concentration of InCl3 and SnCl4 is between 1 ppm and 100 ppm. The intimate mixture may be produced by precipitating indium oxide and tin oxide in chloride media, filtering the precipitate and washing it so that not all the chloride ions are removed. The granulated ITO powder may be formulated into a slurry; the slurry may include a phosphorus compound (e.g. phosphoric acid, a phosphorus oxide, indium phosphate, tin phosphate or phosphorus pentoxide).
Description
A PROCESS FOR THE MANUFACTURE OF A HIGH DENSITY ITO SPUTTERING
TARGET
Field of the invention
This invention relates to a method of manufacturing indium tin oxide (ITO) sputtering targets. In particular, the invention relates to the precipitation and sintering of indium and tin oxides, preparation of an aqueous slurry from the resultant oxide powders, and compacting the slurry in a porous mould using the method of slip casting followed by sintering the resultant compacted target body to yield a high density ITO target.
Background
Transparent conducting thin films of ITO are required for the manufacture of devices such as flat panel display screens and solar cell panels where the ITO film is used to form transparent conducting electrodes. With expansion of the market for flat panel display screens and proliferation of equipment such as Liquid Crystal Display (LCD) screens for televisions! lap top computers and cell phones as well as expansion of the solar cell market, demand for ITO thin films has rocketed. The reason ITO is so commonly used rather than other materials is because of the high light transmission and electrical conductivity of its thin films and their stability over long service life of equipment where they are used, such as LCD televisions. The electrically conducting transparent thin films of ITO are known to be produced by a process called sputtering.
This is a vacuum deposition method that requires an ITO sputtering target. The latter is a shaped body such as a rectangular tile of high density ITO material.
The quality of the ITO target is very important to obtaining satisfactory sputtering and an ITO thin film of quality sufficient for use in LCD related applications especially LCD's based on Thin Film Transistors (TFT). One key parameter is uniform and high target density across the target body. If the target density is not high and not uniform, then problems are encountered during the ITO sputtering process. The sputtering is carried out using a high vacuum plasma process enhanced by a magnetic field. Normally, a conventional ITO target having a flat rectangular plate shape is used. During sputtering, the material from the target surface is eroded in a shape that mirrors the shape of the local magnetic field. The shape often foimed is a curved oval shaped pit called the race track. This means that the target's utility efficiency is not 100% and can be as low as 30%. Although, the utility efficiency can be improved by recycling the used ITO target, the process becomes unviable if the utility efficiency is fuithei adveisely affected by low or non-uniform target density which can cause problems such as nodules' or target cracking during use. Both of these problems have an adverse affect on ITO thin film quality.
In the prior art, ITO targets were prepared by moulding a mixture of indium oxide and tin oxide powders by pressuie moulding processes such as a hot press moulding process to obtain a moulded shape ITO body. However, there are severe limitations to these types of pressure moulding processes. A key issue is that modern LCD production lines, called Generation 7 lines, require large sheets of ITO coated glass.
This in turn means that ITO sputtering lines need large size ITO targets. However, when a large ITO target is prepared by a process such as hot pressing, it is difficult to obtain uniform pressure acioss the target surface leading to the problems of target warp or cracking. Additionally, such a taiget suffers from non-uniformity of density as well as non-uniformity of chemical and physical properties across the target body resulting in non-homogenous sputtering across the target surface during the plasma sputtering process. This in tuin leads to the formation of nodules on the target surface which reduces the target utilisation rate to much less than 30% since nodules adversely affect ITO thin film quality.
To overcome these issues, prior art discloses the pieparation of small tiles. A pluiality of small tiles are assembled in an array to give a large surface area target. However, such tiled targets suffer from the problem of catastrophic electric discharges and heat stiess chipping at the joints which not only reduce target utilisation rate but increase the incidence of nodules and in combination adveisely affect the properties of the ITO thin film.
In another method to overcome the above problems, ITO targets aie manufactured by using a method known as slip casting which can be carried out under pressure or without pressure.
In one slip casting method (JP1117136/88;JP117137/88;JP117138/88), the indium oxide and tin oxide powders are mixed in a liquid such as water with a dispersing agent and a binder to give a slurry which is injected into a water absorbing porous mould made of gypsum. The slurry in the mould then slowly dries as the water leaves the mould via the mould pores. The dispersing agent used is, for example, selected from polycarboxylic acids and the binder is selected, for example, from acrylic emulsions.
This process enables ITO targets of a desired shape and size to be obtained simply by changing the shape and size of the mould. In this method, the slurry is injected into a mould under pressure in the range 50 to 200 kPa. Further increases in target density are obtained by subjecting the post dried target to compression by pressure using a cold isostatic press which applies a pressure not less than 100 MPa. The ITO target is then sintered at 1300 to 1400 °C to obtain a dense target with densities greater than 95%. However, this method suffers from the problem that the yield of targets with densities greater than 99% is low. Further, targets prepared according to this method often crack during cold pressing as well as suffering from nodule formation during sputtering, thereby reducing target utilisation below the economically viable threshold.
Furthermore, during filling of the mould, the mould material is dispersed into the slurry and adheres to the ITO green" tile resulting in contamination of the target by the mould material. These impurities then lead to reduction in the ITO thin film conductivity and problems in the sputtering process such as, for example, the formation of nodules.
In another method (JP 2005324987) to prevent such cracking during manufacture, indium and tin oxide powders, water and an organic binder are mixed and then spray dried to yield a granulated powder which is then milled, high pressure press moulded and then fired to yield the ITO target. However, this is a non-slip casting method and suffers from the same problems as described above such as limitation to small size targets, non uniform densities and abnormal electric discharges during sputtering.
In another embodiment of the prior art (TW588114B) , to overcome the problem of cracking, the ITO target is produced by sintering indium and tin oxides powder mixture, dissolving in aqua regia and filtering with a 0.2 micron filter. After co-precipitation, the oxides are pressed and fired to yield a target which has high density and does not suffer from the problem of nodules. However, this is a long and expensive method. It is also a non-slip casting method so suffers from the problem of size limitation as discussed above.
In another embodiment of the prior art (JP10330926), to obtain a target that increases utilisation during sputtering by minimising nodules and abnormal electric discharges, the density of the target is regulated to achieve »= 99% and also the maximum diameter of voids existing in the sintered target are regulated to less than or equal to 10 microns with less than 1000 voids in one mm2 area of the target. This is achieved by co-precipitation of indium and tin oxides and then burning the oxides in an atmosphere containing hydrogen halide gas such as hydrogen chloride or halogen gas such as chlorine. The powders are then moulded into a compact body by slip casting and firing the slip cast green target. In this way, targets of size greater than 100 cm2 can be obtained with densities »= 99%. However, this method is enormously hazardous due to the use of highly poisonous and unstable gases.
In another embodiment of the prior art (JP7243036), to obtain a target that increases utilisation during sputtering by minimising nodules and abnormal electric discharges, an ITO sintered target is produced from a raw material consisting essentially of indium oxide and tin oxide prepared by powder metallurgical engineering. In this case! the average crystal grain diameter is controlled to <4 micron, the number of voids having 3- 8 micron average diameter is controlled to <900 voids/mm2, the surface roughness Ra is adjusted to <0.5 micron. However, statistically it is very difficult to control all these features simultaneously and ensure consistently good target manufacturing yields.
Summary of the invention
The object of the present invention is to provide a process for mass manufacturing ITO sputtering targets of a large size (preferably »= 100 cm2) and high relative density (preferably »= 99%) for high utilisation efficiency in LCD related sputtering applications.
This objective is obtained by a method that involves (at least in preferred embodiments) the precipitation of indium and tin oxides from chloride solutions, filtering, washing and burning the oxides in the presence of small amounts of chloride «= ppm, preparation of an aqueous slurry of the oxides with additives such as dispersing agent, binder, special high density promoters based on phosphorous compounds, compacting the slurry using slip casting in a specially sugar and chelating agent coated porous mould and then firing the resultant compacted green target body in an oxygen to yield a dark grey high density ITO target.
In accordance with one aspect of the present invention there is provided a method of producing granulated ITO powder for use in the manufacture of ITO sputtering targets.
An intimate mixture of ITO powder and chloride ions is burned in air. The chloride ions are present as lnCl3 and SnCI4 and/or ammonium chloride, and the concentration of 1n013 and SnCI4 in the mixture is between approximately 1 ppm and 100 ppm. The mixture may be burned at a temperature in the range approximately 800 °C -1200 °C, more preferably 900 °C.
The mixture is preferably obtained by precipitating indium and tin oxides in chloride media followed by filtering and washing. The washing may be carried out such that not all chloride ions are removed from the precipitate. It is this that enables the intimate mixture of the chlorides and oxides during the burning operation.
In accordance with another aspect of the present invention there is provided a method of forming an ITO slurry for use in the manufacture of ITO sputtering targets. A slurry of granulated ITO powder and water is formed. A phosphorus compound (such as, for example, phosphoric acid, a phosphorous oxide, indium phosphate or tin phosphate) is also included in the slurry in a concentration between 0.001% and 1% by weight. The phosphorus compound converts to phosphorous in the later firing process, leading to higher densities in the ITO target.
The granulated ITO powder preferably comprises indium(lll) and tin(IV) oxides of surface area 4.5-5.5 m2/g, more preferably 4.5-5.0 m2/g, in concentrations of not less than 75%, more preferably 75-85%, by weight. The slurry may also contain a binder such as an acrylic emulsion and/or a dispersing agent such as a polycarboxylic acid.
The slurry may then be slip cast by injection into a porous mould and left at ambient temperatures to form a "green body". The green body may then be fired at high temperatures in high purity oxygen. It is at this stage that the presence of phosphorus assists the gain of high density in the target.
In accordance with a further aspect of the present invention there is provided a method of manufacturing an ITO spuftering target. A porous mould of gypsum or plaster of paris is coated with a layer of sealing and/or chelating agent. An ITO slurry is then injected into the mould.
The sealing or chelating agent may include a sugar compound such as sucrose or glucose, and/or EGTA, BAPTA or EDTA. In one embodiment the mould is sprayed with a 1% by weight sugar solution with EGTA, BAPTA or EDTA.
A green body may then be produced by leaving the slurry in the mould for a period of time. The green body may then be fired at a temperature between approximately 1000 °C and 1750 °C under high purity oxygen.
It will be appreciated that the various aspects of the invention may be combined.
Detailed description of preferred embodiments
In order that the present invention may be fully understood and readily put into practical effect, there shall now be described by way of non-limitative example only preferred embodiments of the present invention.
After intensive investigations of the prior art and problems of nodule formation, non-uniform target densities, abnormal electric discharges and the adverse affects of these problems on target utilisation rates, the present inventors have succeeded in improving the rate of large size target »= 100 cm2 utilisation in TFT-LCD related sputtering processes by a method that does not involve the use of hazardous gases of the prior art such hydrogen chloride or chlorine nor requires cold isostatic pressing to achieve high and uniform densities.
The improved process enables production of ITO sputtering targets of large size »= 100 cm2 that give ITO thin films of quality suitable for TFT-LCD industry and offer high target utilisation rates by overcoming problems such as nodule formation, target cracking, non-uniform properties across target body and abnormal electric discharges during sputtering.
ITO targets are produced that contain indium(lll) oxide and tin(IV) oxide where the indium(lll) oxide content is not less than 75% by weight. Also, the presence of a third component other than the oxides of indium and tin is permitted for attaining high and uniform target densities whilst minimising target cracking.
In a first stage of the process, indium and tin oxides are precipitated in chloride media, filtered, washed and burned at 800 -1200 °C. The washing is carried out such that not all chloride ions are removed from the precipitate with the result that during the burn-out operation, chlorides present are intimately mixed with the oxides. Whilst not wishing to be bound by theory, it is thought that the chloride ions are attached to oxide particles by weak Van der Waals forces of molecular attraction. The chlorides decompose at the high burn-out temperatures releasing hydrogen chloride and chlorine gas at microscopic levels intimately close to the oxide particles. Again whilst not wishing to be bound by theory, it is thought that the oxidising nature of chlorine assists in keeping the metals in their highest stable oxidation states whilst also assisting in sintering by introducing a gaseous state around the oxide particles. It will be clear to those skilled in the art that this is a more efficient and safer way of introducing chlorine into the oxide powder matrix by decomposition of chloride ions mixed intimately with oxide particles than the hazardous method of JP10330926 mentioned above where chlorine gas is pumped into the oxide sintering ovens.
The resultant granulated indium and tin oxide powder with surface area in the range 4.5 to 5.5 m2/g, preferably 4.5 to 5.0 m2tg, is made into a slurry with water such that the concentration of the oxides is not less than 75% by weight and more preferably in the range 75 -85%. If the concentration is lower, then the resultant target is likely to crack during manufacturing and also to suffer from non-uniform and low densities. The slurry also contains dispersion agents for example such as polycarboxylic acids and binders for examples acrylic emulsions, though not specifically limited to these compounds.
The slurry additionally contains phosphorous added as a phosphorus compound for example phosphoric acid, phosphorus oxide or phosphate salts of indium or tin in concentrations of 0.001% to 1% by weight.
The slurry is injected into a porous mould made of materials such as gypsum, Plaster of Paris or porous polymers. Where gypsum or Plaster of Paris are used as mould materials, the moulds are coated with a thin layer of a sugar compound such as sucrose or glucose by spraying the mould with a 1% by weight sugar solution with EGTA (ethylene glycol tetraacetic acid), BAPTA (1,2-bis(o-aminophenoxy)ethane-N, N, N',N'-tetraacetic acid), or EDTA (ethylenediaminetetraacetic acid). EGTA, BAPTA and EDTA are chelating agents that help to prevent calcium ions from eluting from the mould walls and contaminating the ITO target surface. The filled moulds are left at ambient temperatures. The material of the slurry compacts into a dense shape green body' via the water absorbing action of the porous mould.
The green body' is then fired in a furnace at temperatures of 1000°C -1750 °C under high purity oxygen. The shape and size of the target is not limited and can be altered simply by altering the shape and size of the mould and moulds of size >100 cm2 can be used. Further targets of the desired dimension and size can be obtained without suffering any crack and bending.
According to the processes of the present invention, ITO targets can be prepared with relative density »= 99%.
Examples of embodiments Exam rile 1 lndium(lll) and tin(IV) oxides were co-precipitated from solutions of their chloride compounds. Washing of the precipitates was conducted with deionised water such that -100±50 ppm of chloride remained in the precipitate. The precipitated oxides were then burned at 800 °C to 1200 °C to yield oxide powders with surface areas in the range 4 to 5 m2/g. A thick rectangular polyacrylate board of thickness 10 mm was machined into a master mould and a Plaster of Paris mould was formed using the said master mould. The Plaster of Paris mould of dimensions 60 cm x 30 cm and tile thickness depth of 2 cm was sprayed lightly with a 1% solution of sucrose in a 0.Osmolar aqueous solution of EGTA such that no more than 100 cm3 of the sucrose! EGTA solution was used. A slurry containing 14040 g of indiumOll) oxide powder 99.99% pure of surface area 5 m2/g and 1560 g of tin(IV) oxide powder 99.99% pure of surface a 4.5 m2Ig, 300 g of 45% by weight solution of polycarboxylic acid dispersing agent, 300 g of acrylic emulsion binder of 45% by weight concentration, 1.2g of phosphoric acid and 4800 g of deionised water were placed in a nylon pot of 20000 litre capacity and the whole mixture was thoroughly mixed for 16 hours with a rotating ball mill using yttria stabilised zirconia beads of 12 mm diameter to obtain a slurry for slip casting.
The slurry obtained was thoroughly de-aired using ultrasonic agitation and then poured into the porous mould under atmospheric pressure. The mould was left at 25 °C/45% RH for 48 hours and then carefully separated from the compacted ITO green body. The ITO green body compact was then fired in an oxygen atmosphere at 1600 °C for 4 hours. The fired highly dense ITO target was precision cut, surface machined, cleaned in high purity isopropyl alcohol and air dried to give a commercial working target ready for bonding to a copper backing plate and use in a sputtering process. All above operations were performed in a Class 10000 clean room.
The target obtained had relative density of 99.1% and a surface calcium content of less than 0.002%
Example 2
Using the same method as in Example 1 except that lOg of tin(IV) phosphate was added to the slurry. The target obtained had relative density of 99.2% and a surface calcium content of less than 0.002%
Example 3
Using the same method as in Example 1 except that lOg of indium(IV) phosphate was added to the slurry. The target obtained had a density of 99.4% and a surface calcium content of less than 0.001% As explained above, the efficiency of utilisation of an ITO target during the process of sputtering can be improved according to the invention of this patent application.
Further, the invention provides a process by which a large ITO target of an arbitrary shape can be prepared without the use of hazardous materials such as hydrogen chloride or chlorine gases which are both highly toxic to biological organisms.
Furthermore, ITO targets of relative densities greater than 99% can be prepared with excellent uniformity of density, stoichiornetry, and electrical and thermal conductivities across the target body even with target sizes greater than 100 cm2.
Claims (16)
- <claim-text>CLAIMS: 1. A method of producing granulated ITO powder for use in the manufacture of ITO sputtering targets, comprising: burning in air an intimate mixture of ITO powder and chloride ions present as lnCl3 and SnCI4, wherein the concentration of lnCl3 and SnCI4 in the intimate mixture is between 1 ppm and 100 ppm.</claim-text> <claim-text>2. The method of claim 1, wherein the intimate mixture is burned at a temperature in the range approximately 800 °C-1200 °C.</claim-text> <claim-text>3. The method of claim 2, wherein the intimate mixture is burned at approximately 900 °C.</claim-text> <claim-text>4. The method of claim 1, 2 or 3, wherein the intimate mixture is produced by: precipitating indium oxide and tin oxide in chloride media to produce a precipitate; filtering the precipitate; and washing the precipitate so that not all chloride ions are removed from the precipitate; wherein the washed precipitate forms the mixture.</claim-text> <claim-text>5. The method of any of claims 1 to 4, further comprising forming the granulated ITO powder into a slurry.</claim-text> <claim-text>6. The method of claim 5, wherein the slurry includes a phosphorus compound in a concentration between 0.001% and 1% by weight.</claim-text> <claim-text>7. The method of claim 6, wherein the phosphorus compound is one or more of phosphoric acid, a phosphorous oxide, indium (Ill) phosphate and tin (IV) phosphate.</claim-text> <claim-text>8. The method of claim 7, wherein the phosphorus compound includes phosphorus pentoxide.</claim-text> <claim-text>9. The method of claim 6, 7 or 8, wherein the granulated ITO powder comprises indium(lll) and tin(IV) oxides of surface area 4.5-5.5 m2/g in concentrations of not less than 75% by weight.</claim-text> <claim-text>10. The method of any of claims 6 to 9, wherein the slurry also contains a binder and/or a dispersing agent.</claim-text> <claim-text>11. The method of any of claims 6 to 10, further comprising: providing a porous mould of gypsum or plaster of paris; coating the mould with a layer of sealing and/or chelating agent; and injecting the slurry into the mould.</claim-text> <claim-text>12. The method of claim 11, wherein the sealing or chelating agent includes a sugar compound.</claim-text> <claim-text>13. The method of claim 12, wherein the sugar compound comprises sucrose or glucose.</claim-text> <claim-text>14. The method of claim 11, 12 or 13, wherein the sealing or chelating agent includes at least one of EGTA, BAPTA and EDTA.</claim-text> <claim-text>15. The method of any of claims 11 to 14, wherein the step of coating the mould includes spraying the mould with a sugar solution and EGTA, BAPTA or EDTA.</claim-text> <claim-text>16. The method of any of claims 11 to 15, further comprising producing a green body by leaving the slurry in the mould for a period of time, and firing the green body at a temperature between approximately 1000°C and 175000 under high purity oxygen.Amendments to the claims have been filed as follows.CLAIMS: 1. A method of producing granulated ITO powder for use in the manufacture of ITO sputtering targets, comprising: burning in air an intimate mixture of ITO powder and chloride ions present as lnCl3 and SnCl4, wherein the concentration of lnCl3 and SnCl4 in the intimate mixture is between 1 ppm and 100 ppm.
- 2. The method of claim 1, wherein the intimate mixture is burned at a temperature intherange800 °C-1200 °C.
- 3. The method of claim 2, wherein the intimate mixture is burned at 900 °C.(Y)
- 4. The method of claim 1, 2 or 3, wherein the intimate mixture is produced by: precipitating indium oxide and tin oxide in chloride media to produce a precipitate; o filtering the precipitate; and washing the precipitate so that not all chloride ions are removed from the precipitate; wherein the washed precipitate forms the mixture.
- 5. The method of any of claims 1 to 4, further comprising forming the granulated ITO powder into a slurry.
- 6. The method of claim 5, wherein the slurry is an aqueous slurry and includes a phosphorus compound in a concentration between 0.00 1% and 1% by weight.
- 7. The method of claim 6, wherein the phosphorus compound is one or more of phosphoric acid, a phosphorous oxide, indium (III) phosphate and tin (IV) phosphate.
- 8. The method of claim 7, wherein the phosphorus compound includes phosphorus pentoxide.
- 9. The method of claim 6, 7 or 8, wherein the granulated ITO powder comprises indium(lll) and tin(IV) oxides of surface area 4.5-5.5 m2/g in concentrations of not less than 75% by weight.
- 10. The method of any of claims 6 to 9, wherein the slurry also contains a binder and/or a dispersing agent.
- 11. The method of any of claims 6 to 10, further comprising: providing a porous mould of gypsum or plaster of paris; coating the mould with a layer of sealing and/or chelating agent; and injecting the slurry into the mould.
- 12. The method of claim 11, wherein the sealing or chelating agent includes a (Y) sugar compound.
- 13. The method of claim 12, wherein the sugar compound comprises sucrose or o glucose.
- 14. The method of claim 11, 12 or 13, wherein the sealing or chelating agent includes at least one of EGTA, BAPTA and EDTA.
- 15. The method of any of claims 11 to 14, wherein the step of coating the mould includes spraying the mould with a sugar solution and ECTA, BAPTA or EDTA.
- 16. The method of any of claims 11 to 15, further comprising producing a green body by leaving the slurry in the mould for a period of time, and firing the green body at a temperature between 1000 °C and 1750 °C under high purity oxygen.</claim-text>
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1222458.0A GB2494576B (en) | 2008-05-12 | 2008-05-12 | A process for the manufacture of a high density ITO sputtering target |
HK13105605.1A HK1178874A1 (en) | 2008-05-12 | 2013-05-10 | A process for the manufacture of a high density ito sputtering target |
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GB1222458.0A GB2494576B (en) | 2008-05-12 | 2008-05-12 | A process for the manufacture of a high density ITO sputtering target |
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CN105540643A (en) * | 2016-02-22 | 2016-05-04 | 武汉工程大学 | Multipod-like indium oxide compound sensitive material and preparation and application thereof |
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JP2004123523A (en) * | 2002-09-11 | 2004-04-22 | Sumitomo Chem Co Ltd | Method for producing indium oxide-tin oxide powder |
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JP2004123523A (en) * | 2002-09-11 | 2004-04-22 | Sumitomo Chem Co Ltd | Method for producing indium oxide-tin oxide powder |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN105540643A (en) * | 2016-02-22 | 2016-05-04 | 武汉工程大学 | Multipod-like indium oxide compound sensitive material and preparation and application thereof |
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GB2494576B (en) | 2013-04-24 |
HK1178874A1 (en) | 2013-09-19 |
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