WO2018150621A1 - 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 - Google Patents
酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 Download PDFInfo
- Publication number
- WO2018150621A1 WO2018150621A1 PCT/JP2017/035301 JP2017035301W WO2018150621A1 WO 2018150621 A1 WO2018150621 A1 WO 2018150621A1 JP 2017035301 W JP2017035301 W JP 2017035301W WO 2018150621 A1 WO2018150621 A1 WO 2018150621A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- oxide
- crystal phase
- sintered body
- oxide sintered
- powder
- Prior art date
Links
- 239000004065 semiconductor Substances 0.000 title claims abstract description 298
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 83
- 239000013078 crystal Substances 0.000 claims abstract description 372
- 229910052738 indium Inorganic materials 0.000 claims abstract description 93
- 229910052721 tungsten Inorganic materials 0.000 claims abstract description 83
- 229910052725 zinc Inorganic materials 0.000 claims abstract description 78
- 238000002441 X-ray diffraction Methods 0.000 claims abstract description 45
- 239000000843 powder Substances 0.000 claims description 202
- 239000011701 zinc Substances 0.000 claims description 151
- 238000004544 sputter deposition Methods 0.000 claims description 120
- 239000000203 mixture Substances 0.000 claims description 86
- 238000000034 method Methods 0.000 claims description 80
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 55
- 238000005245 sintering Methods 0.000 claims description 53
- QGLKJKCYBOYXKC-UHFFFAOYSA-N nonaoxidotritungsten Chemical compound O=[W]1(=O)O[W](=O)(=O)O[W](=O)(=O)O1 QGLKJKCYBOYXKC-UHFFFAOYSA-N 0.000 claims description 43
- 229910001930 tungsten oxide Inorganic materials 0.000 claims description 43
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 claims description 35
- 239000002994 raw material Substances 0.000 claims description 35
- 239000012298 atmosphere Substances 0.000 claims description 32
- 229910052760 oxygen Inorganic materials 0.000 claims description 32
- 239000002245 particle Substances 0.000 claims description 31
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 29
- 239000001301 oxygen Substances 0.000 claims description 29
- -1 zinc tungstate compound Chemical class 0.000 claims description 27
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 25
- 239000010937 tungsten Substances 0.000 claims description 25
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 22
- 229910003437 indium oxide Inorganic materials 0.000 claims description 19
- PJXISJQVUVHSOJ-UHFFFAOYSA-N indium(iii) oxide Chemical compound [O-2].[O-2].[O-2].[In+3].[In+3] PJXISJQVUVHSOJ-UHFFFAOYSA-N 0.000 claims description 19
- 238000000465 moulding Methods 0.000 claims description 8
- 239000010408 film Substances 0.000 description 295
- 230000003746 surface roughness Effects 0.000 description 84
- 238000005477 sputtering target Methods 0.000 description 75
- 238000010438 heat treatment Methods 0.000 description 55
- 230000005669 field effect Effects 0.000 description 54
- 239000000758 substrate Substances 0.000 description 47
- 230000015572 biosynthetic process Effects 0.000 description 45
- 230000001965 increasing effect Effects 0.000 description 39
- 238000005259 measurement Methods 0.000 description 34
- 239000007789 gas Substances 0.000 description 27
- 238000002161 passivation Methods 0.000 description 27
- 239000011787 zinc oxide Substances 0.000 description 20
- 229910052751 metal Inorganic materials 0.000 description 16
- 238000002156 mixing Methods 0.000 description 15
- 238000001354 calcination Methods 0.000 description 14
- 229910052984 zinc sulfide Inorganic materials 0.000 description 14
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 12
- 230000000052 comparative effect Effects 0.000 description 12
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 12
- 239000002184 metal Substances 0.000 description 11
- 239000002131 composite material Substances 0.000 description 10
- 238000005001 rutherford backscattering spectroscopy Methods 0.000 description 10
- 239000010409 thin film Substances 0.000 description 10
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 9
- 238000005530 etching Methods 0.000 description 9
- 239000000463 material Substances 0.000 description 9
- 239000012299 nitrogen atmosphere Substances 0.000 description 9
- 230000005540 biological transmission Effects 0.000 description 8
- 230000002950 deficient Effects 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 8
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 7
- 229910052782 aluminium Inorganic materials 0.000 description 7
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 7
- XKRFYHLGVUSROY-UHFFFAOYSA-N argon Substances [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 7
- 238000012790 confirmation Methods 0.000 description 7
- 239000010949 copper Substances 0.000 description 7
- 238000005268 plasma chemical vapour deposition Methods 0.000 description 7
- 229910052710 silicon Inorganic materials 0.000 description 7
- 239000010703 silicon Substances 0.000 description 7
- 229910052814 silicon oxide Inorganic materials 0.000 description 7
- 238000009413 insulation Methods 0.000 description 6
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 6
- 238000002360 preparation method Methods 0.000 description 6
- 238000010298 pulverizing process Methods 0.000 description 6
- 229910021417 amorphous silicon Inorganic materials 0.000 description 5
- 229910001882 dioxygen Inorganic materials 0.000 description 5
- 229910052757 nitrogen Inorganic materials 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 4
- 229910052786 argon Inorganic materials 0.000 description 4
- 238000000151 deposition Methods 0.000 description 4
- 238000001035 drying Methods 0.000 description 4
- 238000011156 evaluation Methods 0.000 description 4
- 238000009616 inductively coupled plasma Methods 0.000 description 4
- 150000002500 ions Chemical group 0.000 description 4
- 238000001755 magnetron sputter deposition Methods 0.000 description 4
- 239000002159 nanocrystal Substances 0.000 description 4
- 238000005211 surface analysis Methods 0.000 description 4
- JBQYATWDVHIOAR-UHFFFAOYSA-N tellanylidenegermanium Chemical compound [Te]=[Ge] JBQYATWDVHIOAR-UHFFFAOYSA-N 0.000 description 4
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 229910052581 Si3N4 Inorganic materials 0.000 description 3
- 125000004429 atom Chemical group 0.000 description 3
- 238000011088 calibration curve Methods 0.000 description 3
- 238000005229 chemical vapour deposition Methods 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 238000002003 electron diffraction Methods 0.000 description 3
- 230000002708 enhancing effect Effects 0.000 description 3
- 125000005843 halogen group Chemical group 0.000 description 3
- 238000004949 mass spectrometry Methods 0.000 description 3
- 229920002120 photoresistant polymer Polymers 0.000 description 3
- 230000000704 physical effect Effects 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 238000001771 vacuum deposition Methods 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- OLBVUFHMDRJKTK-UHFFFAOYSA-N [N].[O] Chemical compound [N].[O] OLBVUFHMDRJKTK-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000011324 bead Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 239000002612 dispersion medium Substances 0.000 description 2
- 238000010894 electron beam technology Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- VSZWPYCFIRKVQL-UHFFFAOYSA-N selanylidenegallium;selenium Chemical compound [Se].[Se]=[Ga].[Se]=[Ga] VSZWPYCFIRKVQL-UHFFFAOYSA-N 0.000 description 2
- 239000006104 solid solution Substances 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- PBYZMCDFOULPGH-UHFFFAOYSA-N tungstate Chemical compound [O-][W]([O-])(=O)=O PBYZMCDFOULPGH-UHFFFAOYSA-N 0.000 description 2
- 238000007088 Archimedes method Methods 0.000 description 1
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- GYHNNYVSQQEPJS-UHFFFAOYSA-N Gallium Chemical compound [Ga] GYHNNYVSQQEPJS-UHFFFAOYSA-N 0.000 description 1
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000002050 diffraction method Methods 0.000 description 1
- 238000001312 dry etching Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000005401 electroluminescence Methods 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 229910052733 gallium Inorganic materials 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 230000009191 jumping Effects 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 239000011812 mixed powder Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 125000004430 oxygen atom Chemical group O* 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000001020 plasma etching Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 229910001404 rare earth metal oxide Inorganic materials 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 238000001694 spray drying Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000001039 wet etching Methods 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02518—Deposited layers
- H01L21/02521—Materials
- H01L21/02565—Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
-
- 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
- C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
- C23C14/08—Oxides
- C23C14/083—Oxides of refractory metals or yttrium
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
- C04B35/495—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 vanadium, niobium, tantalum, molybdenum or tungsten oxides or solid solutions thereof with other oxides, e.g. vanadates, niobates, tantalates, molybdates or tungstates
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
- C04B35/62685—Treating the starting powders individually or as mixtures characterised by the order of addition of constituents or additives
-
- 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
- C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
- C23C14/08—Oxides
- C23C14/086—Oxides of zinc, germanium, cadmium, indium, tin, thallium or bismuth
-
- 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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02107—Forming insulating materials on a substrate
- H01L21/02109—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates
- H01L21/02112—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer
- H01L21/02123—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer the material containing silicon
- H01L21/02164—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer the material containing silicon the material being a silicon oxide, e.g. SiO2
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02107—Forming insulating materials on a substrate
- H01L21/02109—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates
- H01L21/02112—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer
- H01L21/02172—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer the material containing at least one metal element, e.g. metal oxides, metal nitrides, metal oxynitrides or metal carbides
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02107—Forming insulating materials on a substrate
- H01L21/02225—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer
- H01L21/0226—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a deposition process
- H01L21/02263—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a deposition process deposition from the gas or vapour phase
- H01L21/02266—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a deposition process deposition from the gas or vapour phase deposition by physical ablation of a target, e.g. sputtering, reactive sputtering, physical vapour deposition or pulsed laser deposition
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02436—Intermediate layers between substrates and deposited layers
- H01L21/02439—Materials
- H01L21/02488—Insulating materials
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02518—Deposited layers
- H01L21/02521—Materials
- H01L21/02551—Group 12/16 materials
- H01L21/02554—Oxides
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02365—Forming inorganic semiconducting materials on a substrate
- H01L21/02612—Formation types
- H01L21/02617—Deposition types
- H01L21/02631—Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
- H01L29/76—Unipolar devices, e.g. field effect transistors
- H01L29/772—Field effect transistors
- H01L29/78—Field effect transistors with field effect produced by an insulated gate
- H01L29/786—Thin film transistors, i.e. transistors with a channel being at least partly a thin film
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/02—Amorphous compounds
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/50—Solid solutions
- C01P2002/52—Solid solutions containing elements as dopants
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/50—Solid solutions
- C01P2002/52—Solid solutions containing elements as dopants
- C01P2002/54—Solid solutions containing elements as dopants one element only
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/74—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by peak-intensities or a ratio thereof only
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/51—Particles with a specific particle size distribution
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/54—Particles characterised by their aspect ratio, i.e. the ratio of sizes in the longest to the shortest dimension
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/10—Solid density
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
- C04B2235/3231—Refractory metal oxides, their mixed metal oxides, or oxide-forming salts thereof
- C04B2235/3258—Tungsten oxides, tungstates, or oxide-forming salts thereof
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
- C04B2235/3231—Refractory metal oxides, their mixed metal oxides, or oxide-forming salts thereof
- C04B2235/3258—Tungsten oxides, tungstates, or oxide-forming salts thereof
- C04B2235/326—Tungstates, e.g. scheelite
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
- C04B2235/3284—Zinc oxides, zincates, cadmium oxides, cadmiates, mercury oxides, mercurates or oxide forming salts thereof
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
- C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
- C04B2235/54—Particle size related information
- C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
- C04B2235/5436—Particle size related information expressed by the size of the particles or aggregates thereof micrometer sized, i.e. from 1 to 100 micron
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
- C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
- C04B2235/54—Particle size related information
- C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
- C04B2235/5445—Particle size related information expressed by the size of the particles or aggregates thereof submicron sized, i.e. from 0,1 to 1 micron
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/74—Physical characteristics
- C04B2235/77—Density
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/74—Physical characteristics
- C04B2235/78—Grain sizes and shapes, product microstructures, e.g. acicular grains, equiaxed grains, platelet-structures
- C04B2235/786—Micrometer sized grains, i.e. from 1 to 100 micron
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/74—Physical characteristics
- C04B2235/78—Grain sizes and shapes, product microstructures, e.g. acicular grains, equiaxed grains, platelet-structures
- C04B2235/788—Aspect ratio of the grains
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/80—Phases present in the sintered or melt-cast ceramic products other than the main phase
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
- C04B2235/963—Surface properties, e.g. surface roughness
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
- H01L29/76—Unipolar devices, e.g. field effect transistors
- H01L29/772—Field effect transistors
- H01L29/78—Field effect transistors with field effect produced by an insulated gate
- H01L29/786—Thin film transistors, i.e. transistors with a channel being at least partly a thin film
- H01L29/7869—Thin film transistors, i.e. transistors with a channel being at least partly a thin film having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate
Definitions
- the present invention provides an oxide sintered body that can be suitably used as a sputtering target for forming an oxide semiconductor film by a sputtering method, a method for producing the oxide sintered body, a sputtering target (sputtering target) including the oxide sintered body,
- the present invention also relates to a method for manufacturing a semiconductor device including an oxide semiconductor film formed by sputtering (sputtering) using the sputtering target.
- a thin film EL (electroluminescence) display device an organic EL display device, etc.
- amorphous silicon (a-Si) film has been mainly used as a semiconductor film functioning as a channel layer of a TFT (thin film transistor) as a semiconductor device.
- a-Si amorphous silicon
- IGZO Indium (In), gallium (Ga), and zinc (Zn) as a material to replace a-Si, that is, an In—Ga—Zn-based composite oxide (also referred to as “IGZO”).
- IGZO-based oxide semiconductor can be expected to have higher carrier mobility than a-Si.
- Patent Document 1 discloses that an oxide semiconductor film containing IGZO as a main component is formed by a sputtering method using an oxide sintered body as a target.
- Patent Document 2 discloses an oxide sintered body containing In and tungsten (W) as a material suitably used for forming an oxide semiconductor film by a sputtering method or the like. .
- Patent Document 3 discloses an oxide sintered body containing In and Zn.
- An oxide sintered body is an oxide sintered body containing indium, tungsten, and zinc, is a main component of the oxide sintered body, and includes a bixbite type crystal phase.
- the oxide sintered body includes a first crystal phase and a second crystal phase having a first diffraction peak at a position larger than 34.74 deg of 2 ⁇ in X-ray diffraction and smaller than 34.97 deg. 4 g / cm 3 to 7.5 g / cm 3 or less, and the content of tungsten with respect to the total of indium, tungsten and zinc in the oxide sintered body is more than 0.01 atomic% and 5.0 atomic% or less.
- the zinc content relative to the sum of indium, tungsten and zinc in the oxide sintered body is 1.2 atomic% or more and less than 50 atomic%,
- the zinc atomic ratio is greater than 1.0 and less than 20000.
- a sputter target according to another aspect of the present invention includes the oxide sintered body according to the above aspect.
- a method for manufacturing a semiconductor device according to still another aspect of the present invention is a method for manufacturing a semiconductor device including an oxide semiconductor film, the step of preparing the sputter target of the above aspect, and a sputtering method using the sputter target. Forming an oxide semiconductor film.
- the method for manufacturing an oxide sintered body according to still another aspect of the present invention is a method for manufacturing the oxide sintered body according to the above aspect, and prepares a primary mixture of indium oxide powder and tungsten oxide powder.
- Forming a calcined powder by heat-treating the primary mixture preparing a secondary mixture of raw material powders containing the calcined powder, and molding the secondary mixture.
- a step of forming an oxide sintered body by sintering the formed body, and the step of forming the calcined powder includes 700 ° C. or higher and 1400 ° C. in an oxygen-containing atmosphere.
- the method for producing an oxide sintered body according to still another aspect of the present invention is a method for producing an oxide sintered body according to the above aspect, wherein a primary mixture of zinc oxide powder and tungsten oxide powder is prepared. Forming a calcined powder by heat-treating the primary mixture, preparing a secondary mixture of raw material powders containing the calcined powder, and molding the secondary mixture. A step of forming an oxide sintered body by sintering the compact, and the step of forming the calcined powder is performed at 550 ° C. or higher and 1200 ° C. in an oxygen-containing atmosphere. Forming a double oxide powder containing zinc and tungsten as the calcined powder by heat-treating the primary mixture at a temperature below.
- FIG. 1A is a schematic plan view illustrating an example of a semiconductor device according to one embodiment of the present invention.
- 1B is a schematic cross-sectional view taken along line IB-IB shown in FIG. 1A.
- FIG. 2 is a schematic cross-sectional view illustrating another example of a semiconductor device according to one embodiment of the present invention.
- FIG. 3 is a schematic cross-sectional view illustrating still another example of the semiconductor device according to one aspect of the present invention.
- 4A is a schematic cross-sectional view showing an example of a method for manufacturing the semiconductor device shown in FIG. 1A and FIG. 1B.
- 4B is a schematic cross-sectional view showing an example of a method for manufacturing the semiconductor device shown in FIG. 1A and FIG. 1B.
- FIG. 1A is a schematic plan view illustrating an example of a semiconductor device according to one embodiment of the present invention.
- 1B is a schematic cross-sectional view taken along line IB-IB shown in FIG. 1A.
- FIG. 4C is a schematic cross-sectional view showing an example of a method for manufacturing the semiconductor device shown in FIGS. 1A and 1B.
- FIG. 4D is a schematic cross-sectional view showing an example of a manufacturing method of the semiconductor device shown in FIGS. 1A and 1B.
- FIG. 5A is a schematic cross-sectional view showing an example of a manufacturing method of the semiconductor device shown in FIG.
- FIG. 5B is a schematic cross-sectional view showing an example of a manufacturing method of the semiconductor device shown in FIG.
- FIG. 5C is a schematic cross-sectional view showing an example of a manufacturing method of the semiconductor device shown in FIG.
- FIG. 5D is a schematic cross-sectional view showing an example of a method for manufacturing the semiconductor device shown in FIG.
- a problem with the TFT including the IGZO-based oxide semiconductor film described in Patent Document 1 as a channel layer is that the field-effect mobility is as low as about 10 cm 2 / Vs.
- Patent Document 2 a TFT including an oxide semiconductor film formed using an oxide sintered body containing In and W as a channel layer has been proposed, but the reliability of the TFT has not been studied. .
- a thin film formed using the oxide sintered body described in Patent Document 3 is a transparent conductive film, and has a lower electrical resistance than a semiconductor film such as a thin film used for a channel layer of a TFT, for example.
- the oxide sintered body is desired to have a high density (apparent density). In the oxide sintered body described in Patent Document 3, this is used.
- the apparent density cannot be increased unless the sintering temperature during preparation is increased. However, if the sintering temperature is set to a high temperature, the temperature rise time and the temperature fall time become long, and the amount of electric power increases to maintain the sintering atmosphere at a high temperature, resulting in a decrease in productivity. Further, when the sintering temperature is increased, the raw material tungsten oxide is evaporated, and an oxide sintered body containing W cannot be obtained.
- Patent Document 4 it is described that the surface roughness during the production of a sputter target is reduced.
- the surface immediately after the production of the target is etched by sputtering during use, and the use is continued with the surface roughness formed while being etched during use.
- the roughness of the etched target surface is large, the roughness of a film obtained by sputtering the target is also large.
- the present invention provides an oxide sintered body capable of exhibiting a high apparent density even at a relatively low sintering temperature and reducing the surface roughness of the sputter target during sputtering when applied to the sputter target.
- An object of the present invention is to provide a manufacturing method thereof, a sputtering target including the oxide sintered body, and a manufacturing method of a semiconductor device including an oxide semiconductor film formed using the sputtering target.
- an oxide sintered body that can exhibit a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputter target during sputtering when applied to the sputter target. And a method for manufacturing the same. Moreover, according to the above, it is possible to provide a semiconductor device capable of achieving both high field effect mobility and high reliability under light irradiation.
- An oxide sintered body is an oxide sintered body containing indium (In), tungsten (W), and zinc (Zn), and the oxide sintered body
- a first crystal phase that is a main component and includes a bixbite type crystal phase, and a second crystal phase having a first diffraction peak at a position greater than 34.74 deg of 2 ⁇ in X-ray diffraction and less than 34.97 deg.
- the second crystal phase is included in a part of the oxide sintered body.
- the oxide sintered body of the present embodiment has an apparent density of greater than 6.4 g / cm 3 and 7.5 g / cm 3 or less, and the inclusion of W with respect to the total of In, W, and Zn in the oxide sintered body
- the ratio (hereinafter also referred to as “W content” of the oxide sintered body) is greater than 0.01 atomic% and 5.0 atomic% or less, and the sum of In, W, and Zn in the oxide sintered body Zn content (hereinafter also referred to as “Zn content” of the oxide sintered body) is 1.2 atomic% or more and less than 50 atomic%, and the atomic ratio of Zn to W in the oxide sintered body (Hereinafter also referred to as “Zn / W ratio” of the oxide sintered body) is larger than 1.0 and smaller than 20000.
- a high apparent density (meaning an apparent density after sintering and also called a sintered density) can be exhibited even at a relatively low sintering temperature
- the surface roughness of the sputtering target during sputtering can be reduced.
- the apparent density within the above range is advantageous when the oxide sintered body of the present embodiment is used as a sputtering target.
- the oxide sintered body of this embodiment can be suitably used as a sputtering target for forming an oxide semiconductor film (for example, an oxide semiconductor film functioning as a channel layer) included in a semiconductor device.
- an oxide semiconductor film having a small surface roughness can be formed. Moreover, according to the oxide sintered body of the present embodiment, it is possible to obtain a semiconductor device with high field effect mobility and high reliability under light irradiation.
- the oxide sintered body of the present embodiment is a crystal phase different from the first crystal phase, and can include a third crystal phase containing zinc.
- the particles constituting the third crystal phase preferably have an average major axis diameter of 3 ⁇ m to 50 ⁇ m and an average aspect ratio of 1.5 to 50. This is to realize an oxide sintered body that has a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputtering target during sputtering when applied to the sputtering target. It is also advantageous for enhancing the field effect mobility and reliability of the semiconductor device under light irradiation.
- the third crystal phase is preferably dispersed in the first crystal phase. This is advantageous when the oxide sintered body of the present embodiment is used as a sputtering target.
- the third crystal phase includes a fourth crystal phase having a second diffraction peak at a position larger than 31.77 deg of 2 ⁇ in X-ray diffraction and smaller than 32.00 deg. be able to.
- the fourth crystal phase is a phase that can be included in a part of the oxide sintered body.
- the inclusion of the fourth crystal phase has a high apparent density even at a relatively low sintering temperature, and an oxide sintered body capable of reducing the surface roughness of the sputter target during sputtering when applied to the sputter target. This is advantageous in realizing the above-mentioned characteristics, and is also advantageous in improving the field effect mobility and reliability under light irradiation of the semiconductor device.
- the ratio Ia / Ib between the peak intensity Ia of the first diffraction peak and the peak intensity Ib of the second diffraction peak can be 0.05 or more and 3 or less.
- Ia / Ib is 0.05 or more and 3 or less, the apparent density is high even at a relatively low sintering temperature, and the surface roughness of the sputtering target during sputtering can be reduced when applied to the sputtering target. This is advantageous in realizing an oxide sintered body that can be produced, and is also advantageous in increasing the field-effect mobility and reliability of the semiconductor device under light irradiation.
- the third crystal phase may include a fifth crystal phase that is a zinc tungstate compound crystal phase. This is to realize an oxide sintered body that has a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputtering target during sputtering when applied to the sputtering target. It is also advantageous for enhancing the field effect mobility and reliability of the semiconductor device under light irradiation.
- the first crystal phase may further include an indium tungstate compound crystal phase. This is to realize an oxide sintered body that has a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputtering target during sputtering when applied to the sputtering target. It is also advantageous for enhancing the field effect mobility and reliability of the semiconductor device under light irradiation.
- a sputter target according to another embodiment of the present invention includes the oxide sintered body of the above embodiment.
- the surface roughness of the sputtering target during sputtering can be reduced, and as a result, the surface roughness of the oxide semiconductor film to be formed can be reduced.
- the sputter target of this embodiment includes the oxide sintered body of the above embodiment, in order to form an oxide semiconductor film of a semiconductor device with high field effect mobility and high reliability under light irradiation by a sputtering method. Preferably used.
- a method for manufacturing a semiconductor device is a method for manufacturing a semiconductor device including an oxide semiconductor film, the step of preparing the sputter target of the above embodiment, and the sputter target And forming the oxide semiconductor film by sputtering using a sputtering method. Since the semiconductor device obtained by the manufacturing method of this embodiment includes an oxide semiconductor film formed by sputtering using the sputtering target of the above embodiment, the semiconductor device can have an oxide semiconductor film with low surface roughness. In addition, high field-effect mobility and reliability under light irradiation can be shown.
- the semiconductor device described here is not particularly limited, but a TFT (thin film transistor) including an oxide semiconductor film formed by a sputtering method using the sputtering target of the above embodiment as a channel layer is a preferable example.
- the W content relative to the total of In, W, and Zn in the obtained oxide semiconductor film (hereinafter, also referred to as “W content” of the oxide semiconductor film). ) Is greater than 0.01 atomic% and equal to or less than 5.0 atomic%, and the Zn content relative to the total of In, W, and Zn in the oxide semiconductor film (hereinafter referred to as “Zn content” of the oxide semiconductor film) Is 1.2 atomic% or more and less than 50 atomic%, and the atomic ratio of Zn to W in the oxide semiconductor film (hereinafter also referred to as “Zn / W ratio” in the oxide semiconductor film) is 1. It is preferably larger than 0 and smaller than 20000. Since the semiconductor device obtained by the manufacturing method of this embodiment includes an oxide semiconductor film formed using the sputter target of the above embodiment, high field-effect mobility and reliability under light irradiation may be exhibited. it can.
- the obtained oxide semiconductor film can be composed of at least one of nanocrystalline oxide and amorphous oxide. This is advantageous in increasing the field effect mobility and the reliability under light irradiation in a semiconductor device including an oxide semiconductor film as a channel layer, for example.
- a method for manufacturing an oxide sintered body according to still another embodiment of the present invention is a method for manufacturing an oxide sintered body according to the above-described embodiment, and includes an indium oxide powder and a tungsten oxide powder.
- a step of preparing a primary mixture, a step of forming a calcined powder by heat-treating the primary mixture, a step of preparing a secondary mixture of raw material powders including the calcined powder, and forming the secondary mixture The step of forming a sintered body and the step of forming an oxide sintered body by sintering the molded body, and the step of forming the calcined powder is performed at 700 ° C. or higher and lower than 1400 ° C. in an oxygen-containing atmosphere.
- the apparent density is high even at a relatively low sintering temperature, and it can be suitably used as a sputtering target.
- An oxide sintered body capable of reducing the surface roughness of the sputter target can be obtained relatively easily.
- the double oxide may include an In 6 WO 12 type crystal phase. This is advantageous in obtaining an oxide sintered body that has a high apparent density and can reduce the surface roughness of the sputtering target during sputtering when applied to the sputtering target.
- a method for manufacturing an oxide sintered body according to still another embodiment of the present invention is a method for manufacturing an oxide sintered body according to the above-described embodiment, and includes a zinc oxide powder and a tungsten oxide powder.
- a step of preparing a primary mixture, a step of forming a calcined powder by heat-treating the primary mixture, a step of preparing a secondary mixture of raw material powders including the calcined powder, and forming the secondary mixture The step of forming a calcined powder including the step of forming a molded body by sintering and the step of forming an oxide sintered body by sintering the molded body is performed at 550 ° C. or more and less than 1200 ° C.
- the apparent density is high even at a relatively low sintering temperature, and it can be suitably used as a sputtering target.
- An oxide sintered body capable of reducing the surface roughness of the sputter target can be obtained relatively easily.
- the double oxide may include a ZnWO 4 type crystal phase. This is advantageous in obtaining an oxide sintered body that has a high apparent density and can reduce the surface roughness of the sputtering target during sputtering when applied to the sputtering target.
- the tungsten oxide powder is composed of a WO 3 crystal phase, a WO 2 crystal phase, and a WO 2.72 crystal phase. It can contain at least one crystalline phase selected from the group. This is advantageous in obtaining an oxide sintered body that has a high apparent density and can reduce the surface roughness of the sputtering target during sputtering when applied to the sputtering target. For example, in a semiconductor device including a channel layer, it is advantageous for increasing the field effect mobility and increasing the reliability under light irradiation.
- the tungsten oxide powder may have a median particle diameter d50 of 0.1 ⁇ m or more and 4 ⁇ m or less. This is advantageous in obtaining an oxide sintered body that has a high apparent density and can reduce the surface roughness of the sputtering target during sputtering when applied to the sputtering target.
- the oxide sintered body of the present embodiment is an oxide sintered body containing indium (In), tungsten (W), and zinc (Zn).
- the oxide sintered body of the present embodiment includes a first crystal phase that is a main component of the oxide sintered body and includes a bixbyite crystal phase, and 34.97 deg which is larger than 34.74 deg of 2 ⁇ in X-ray diffraction. And a second crystal phase having a first diffraction peak at a smaller position. The second crystal phase is included in a part of the oxide sintered body.
- the oxide sintered body of the present embodiment has an apparent density of greater than 6.4 g / cm 3 and 7.5 g / cm 3 or less, and a W content of greater than 0.01 atomic% and 5.0 atomic% or less.
- the Zn content is 1.2 atomic% or more and less than 50 atomic%, and the Zn / W ratio is larger than 1.0 and smaller than 20000.
- the oxide sintered body of the present embodiment can be suitably used as a sputtering target for forming an oxide semiconductor film (for example, an oxide semiconductor film functioning as a channel layer) of a semiconductor device.
- an oxide semiconductor film for example, an oxide semiconductor film functioning as a channel layer
- the oxide sintered body of this embodiment when applied to a sputter target, the surface roughness of the sputter target during sputtering can be reduced.
- an oxide semiconductor film having a small surface roughness can be formed.
- the first crystal phase is a main component of the oxide sintered body and is an indium high-content crystal phase described later including at least a bixbite type crystal phase.
- the “bixbite type crystal phase” means a bixbite crystal phase, and a phase in which at least one of the metal elements other than In is included in at least a part of the bixbite crystal phase, A generic term for those having the same crystal structure.
- the bixbite crystal phase is one of the crystal phases of indium oxide (In 2 O 3 ), and refers to the crystal structure defined by JCPDS card 6-0416, which is a rare earth oxide C-type phase (or C-rare). Also called soil structure phase.
- bixbite type crystal phase can be identified by X-ray diffraction. That is, the existence of a bixbite type crystal phase is confirmed by X-ray diffraction, and the spacing between each plane can be measured.
- the measurement conditions for X-ray diffraction the conditions shown in the following “(2) Second crystal phase” are employed.
- the first crystal phase including the bixbite type crystal phase is the main component of the oxide sintered body” means that in the oxide sintered body, the bixbite type crystal phase, the indium tungstate compound crystal phase, etc. This means that the ratio of the indium-rich crystal phase containing In in terms of content (the indium-rich crystal phase occupancy) is 50% or more.
- the “indium-rich crystal phase” is identified as follows. First, a sample is taken from a part of the oxide sintered body, and the surface of the sample is polished and smoothed. Next, using SEM-EDX (scanning secondary electron microscope with an energy dispersive fluorescence X-ray analyzer), the surface of the sample is observed with SEM (scanning secondary electron microscope), and each crystal particle is observed. The metal elemental composition ratio is analyzed by EDX (energy dispersive fluorescence X-ray analyzer). Then, the crystal particles are grouped based on the tendency of the composition ratio of the metal elements of the crystal particles.
- SEM-EDX scanning secondary electron microscope with an energy dispersive fluorescence X-ray analyzer
- the crystal grains of group B are the first crystal phase (such as In 2 O 3 phase).
- the first crystal phase may include an indium tungstate compound crystal phase in addition to the bixbyite crystal phase.
- the “indium-rich crystal phase occupancy ratio” in the oxide sintered body is defined as the ratio (percentage) of the area of the indium-rich crystal phase (group B) to the measurement surface of the oxide sintered body. Is done.
- the oxide sintered body according to this embodiment including the first crystal phase (indium-rich crystal phase) as a main component has an indium-rich crystal phase occupancy of 50% or more according to this definition.
- W and / or Zn may be dissolved in at least a part thereof.
- the oxide sintered body according to the present embodiment when W and / or Zn is dissolved in at least a part of the bixbite type crystal phase included in the first crystal phase, it is defined in JCPDS card 6-0416. It becomes wider or narrower than the surface spacing.
- X-ray diffraction the peak position shifts to the high angle side or shifts to the low angle side. This peak shift is confirmed, and SEM-EDX (scanning secondary electron microscope with an energy dispersive fluorescent X-ray analyzer) and TEM-EDX (transmission with an energy dispersive fluorescent X-ray analyzer) are used.
- the bixbite type crystal phase contained in the first crystal phase contains W and / or Zn. It can be determined that is dissolved.
- the presence elements are identified using ICP (inductively coupled plasma) mass spectrometry, SEM-EDX, and other element identification methods, and the presence of W and / or Zn together with In is confirmed. It can also be determined that W and / or Zn is solid-solved in the bixbite type crystal phase contained in the first crystal phase when the oxide of W and / or Zn is not confirmed by diffraction.
- ICP inductively coupled plasma
- the first crystal phase may further include an indium tungstate compound crystal phase.
- the peak intensity I400 of the bixbite type crystal phase (400) plane and the peak intensity I122 of the indium tungstate compound (122) plane The peak intensity ratio (I122 / I400) is usually 0 or more and 0.3 or less.
- indium tungstate compound crystal phase is a crystal phase mainly composed of In, W and O. Examples thereof include an In 6 WO 12 crystal phase and an InW 3 O 9 crystal phase.
- the In 6 WO 12 crystal phase is a trigonal crystal structure and is an indium tungstate compound crystal phase having a crystal structure defined by JCPDS card 01-074-1410. As long as the crystal system is shown, oxygen may be deficient or metal may be dissolved, and the lattice constant may be changed.
- the InW 3 O 9 crystal phase has a hexagonal crystal structure and is an indium tungstate compound crystal phase having a crystal structure defined by JCPDS Card 33-627. As long as the crystal system is shown, oxygen may be deficient or metal may be dissolved, and the lattice constant may be changed.
- the presence of the indium tungstate compound crystal phase can be confirmed by the presence of a peak attributed to the “indium tungstate compound crystal phase” in X-ray diffraction. For example, it can be confirmed by the presence of peaks attributed to the above-mentioned In 6 WO 12 crystal phase and InW 3 O 9 crystal phase.
- the measurement conditions for X-ray diffraction the conditions shown in the following “(2) Second crystal phase” are employed.
- the second crystal phase is a crystal phase different from the first crystal phase, and has a first diffraction peak at a position larger than 34.74 deg of 2 ⁇ in X-ray diffraction and smaller than 34.97 deg. Crystalline phase.
- the oxide sintered body of the present embodiment including the first crystal phase and the second crystal phase different from the first crystal phase can exhibit a high apparent density even at a relatively low sintering temperature, and the sputter target being sputtered.
- the surface roughness can be reduced.
- the position of the first diffraction peak is preferably smaller than 34.90 deg of 2 ⁇ from the viewpoint of reducing the apparent density and the surface roughness of the sputter target during sputtering.
- the second crystal phase is included in a part of the oxide sintered body.
- the presence of the second crystal phase can be confirmed by X-ray diffraction.
- X-ray diffraction is measured under the following conditions or equivalent conditions.
- the first diffraction peak is observed at a position larger than 34.74 deg of 2 ⁇ in X-ray diffraction and smaller than 34.97 deg means that the surface interval is larger than 2.56 ⁇ and smaller than 2.58 ⁇ . It has been clarified that the first diffraction peak does not coincide with the diffraction peak position of an oxide or composite oxide composed of one or more of In, W and Zn and an oxygen atom. Examples of the oxide include In 2 O 3 phase which is a bixbite type crystal phase, hexagonal wurtzite crystal ZnO, monoclinic WO 3 and the like.
- the composite oxide examples include ZnWO 4 , In 6 WO 12 , and In 2 O 3 (ZnO) m (m is a natural number).
- the oxide sintered body of the present embodiment further including the above can exhibit a high apparent density even at a relatively low sintering temperature, and can reduce the surface roughness of the sputter target during sputtering. According to the oxide sintered body, field effect mobility and reliability under light irradiation of a semiconductor device including an oxide semiconductor film formed using the oxide sintered body as a channel layer can be increased.
- the oxide sintered body of the present embodiment has an apparent density greater than 6.4 g / cm 3 and 7.5 g / cm 3 or less.
- the oxide sintered body of the present embodiment preferably has a relative density (relative density / theoretical density) of 94% or more, which is the ratio of the apparent density to the theoretical density.
- the apparent density within the above range is advantageous when the oxide sintered body of the present embodiment is used as a sputtering target.
- the apparent density of the oxide sintered body is preferably as high as possible.
- the low apparent density of the oxide sintered body means that there are many voids in the oxide sintered body.
- the sputter target is used while its surface is etched with argon ions during use. Therefore, if there are vacancies in the oxide sintered body, they are exposed during film formation and the internal gas is released, so that the gas released from the target is mixed into the deposited oxide semiconductor thin film. As a result, the film characteristics deteriorate.
- the oxide sintered body of the present embodiment has a W content greater than 0.01 atomic% and 5.0 atomic% or less, a Zn content of 1.2 atomic% or more and less than 50 atomic%, and Zn / W ratio is larger than 1.0 and smaller than 20000.
- the W content, Zn content, and Zn / W ratio are in the above ranges because the oxide has a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputter target during sputtering. It is advantageous for realizing a sintered body, and also improves field effect mobility and reliability under light irradiation of a semiconductor device including an oxide semiconductor film formed using an oxide sintered body as a channel layer. It is advantageous also in raising.
- the W content of the oxide sintered body is preferably 0.05 atomic percent or more and 3 atomic percent or less, more preferably 2 atomic percent. It is as follows. When the W content of the oxide sintered body is 0.01 atomic% or less, in a semiconductor device including an oxide semiconductor film formed using the oxide sintered body as a channel layer, reliability under light irradiation It becomes low. When the W content of the oxide sintered body exceeds 5.0 atomic%, in a semiconductor device including an oxide semiconductor film formed using a sputtering target including the oxide sintered body as a channel layer, a field effect Mobility will be low.
- the range of the W content of the oxide sintered body is determined by the characteristics of the semiconductor device including the oxide semiconductor film formed using the oxide sintered body of the present embodiment as a channel layer.
- the W content of the oxide semiconductor film usually indicates a value corresponding to the W content of the oxide sintered body.
- the W content of the oxide semiconductor film does not necessarily match the W content of the oxide sintered body.
- the W content of the oxide sintered body is larger than 0.01 atomic% and not larger than 5.0 atomic%, preferably 0.01 atomic%. More than 3 atomic%, more preferably more than 0.01 atomic% and not more than 1 atomic%, still more preferably less than 0.5 atomic%.
- the W content of the oxide sintered body is 0.01 atomic% or less, the apparent density of the oxide sintered body tends to be too low.
- the W content of the oxide sintered body exceeds 5.0 atomic%
- the oxide sintered body is applied to the sputter target, the surface roughness of the sputter target during sputtering increases, and as a result, The surface roughness of the oxide semiconductor film to be formed also increases.
- the W element Since the W element has a high atomic weight, the sputtering rate is low, so that the W-containing crystal phase is less likely to be etched than the other phases during sputtering, and tends to be convex on the target surface.
- the W content of the oxide sintered body is lowered, the area ratio of the crystal phase containing W present on the target surface is reduced, so that convex portions are reduced during sputtering and the surface roughness can be reduced. .
- An oxide sintered body obtained by mixing indium oxide and tungsten oxide generally has a small apparent density.
- the apparent density can be increased by adding Zn and increasing the contact points between W and Zn
- the desired W content determined in consideration of the characteristics of the semiconductor device is greater than 0.01 atomic%. Since the amount is as small as 0 atomic% or less, it is preferable to increase the Zn content in order to realize an oxide sintered body having a higher apparent density.
- the Zn content is less than 1.2 atomic%, it tends to be difficult to obtain a sufficiently high apparent density.
- the Zn content is 50 atomic% or more, the electric resistance of the oxide sintered body increases, and it tends to be difficult to perform sputtering by applying a DC voltage. Zn content rate becomes like this.
- the Zn / W ratio is preferably 15 or more.
- the Zn / W ratio is 20000 or more, the electric resistance of the oxide sintered body increases, and it tends to be difficult to perform sputtering by applying a DC voltage. From this viewpoint, the Zn / W ratio is preferably 100 or less.
- the contents of In, Zn, and W in the oxide sintered body can be measured by ICP mass spectrometry.
- the oxide sintered body of the present embodiment can exhibit a high apparent density even at a relatively low sintering temperature, and can reduce the surface roughness of the sputter target during sputtering when applied to the sputter target. it can.
- the oxide sintered body of the present embodiment can be suitably used as a sputtering target for forming an oxide semiconductor film (for example, an oxide semiconductor film functioning as a channel layer) of a semiconductor device. According to the sintered body, it is possible to obtain a semiconductor device with high field effect mobility and high reliability under light irradiation.
- the oxide sintered body of the present embodiment is preferably a crystal phase different from the first crystal phase and includes a third crystal phase containing zinc (Zn).
- the inclusion of the third crystal phase is advantageous in realizing an oxide sintered body that has a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputtering target during sputtering.
- it is advantageous in increasing the field-effect mobility and reliability under light irradiation of a semiconductor device including an oxide semiconductor film formed using an oxide sintered body as a channel layer.
- the third crystal phase may be the same phase as the second crystal phase.
- the third crystal phase is a phase that can be included in part of the oxide sintered body.
- the third crystal phase is a crystal phase containing Zn, and more typically a phase in which the Zn content [the Zn content (atomic%) relative to the sum of In, W and Zn] is higher than that of the first crystal phase. is there.
- the presence of the third crystal phase can be confirmed by surface analysis using SEM-EDX performed when obtaining the indium-rich crystal phase occupancy ratio.
- the crystal phase constituting the crystal particles is the third crystal phase.
- the third crystal phase preferably has a Zn content of 50 atomic% or more.
- the Zn content of the third crystal phase is more Preferably it is 60 atomic% or more, More preferably, it is 70 atomic% or more.
- the Zn content of the third crystal phase may be 100 atomic%.
- the third crystal phase may be at least one crystal phase selected from the group consisting of a fourth crystal phase described later, a fifth crystal phase which is a zinc tungstate compound crystal phase described later, and a hexagonal wurtzite crystal phase.
- the third crystal phase may consist of only one type of crystal phase or may contain two or more types of crystal phases.
- the crystal grains constituting the third crystal phase preferably have an average major axis diameter of 3 ⁇ m to 50 ⁇ m and an average aspect ratio of 1.5 to 50. This is advantageous in realizing an oxide sintered body that has a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputter target during sputtering. This is also advantageous in increasing the field-effect mobility and reliability under light irradiation of a semiconductor device including an oxide semiconductor film formed using a sintered body as a channel layer.
- the average major axis diameter and average aspect ratio are obtained as follows.
- group A which is the third crystal phase, is classified as the first crystal phase. It is observed in a dark gray color compared to Group B.
- the major axis length and minor axis length of the crystal grains constituting the third crystal phase observed in dark gray in the backscattered electron image taken at 500 times are measured, and the ratio of the major axis length to the minor axis length (long
- the aspect ratio is calculated (axis length / short axis length).
- the minor axis length is measured at a position that is 1/2 the major axis length.
- the third crystal phase to be measured does not have to be a single crystal, and may be a particle in which polycrystals are gathered together.
- One independent third crystal phase region surrounded by the first crystal phase may be used. Measure as one particle.
- 100 short axis lengths and 100 long axis lengths of the third crystal phase in the 170 ⁇ m ⁇ 250 ⁇ m field of the backscattered electron image taken at 500 times are measured randomly, and the long axis length is measured in order from the longest.
- the average value of 20 from the 3rd position to the 22nd position arranged in the above is defined as the average major axis diameter.
- the average major axis diameter is 3 ⁇ m or more and 50 ⁇ m or less, the apparent density of the oxide sintered body is high, and an oxide sintered body capable of reducing the surface roughness of the sputtering target during sputtering is realized. It is advantageous.
- the average major axis diameter is smaller than 3 ⁇ m, the surface roughness of the sputtering target during sputtering tends to be difficult to decrease.
- the average major axis diameter is larger than 50 ⁇ m, a sufficiently high apparent density tends not to be obtained, and the surface roughness of the sputter target during sputtering tends to be difficult to decrease.
- the average major axis diameter is more preferably 10 ⁇ m or more, and further preferably 15 ⁇ m or more.
- the average major axis diameter is more preferably 40 ⁇ m or less, and further preferably 30 ⁇ m or less.
- An average aspect ratio of 1.5 or more and 50 or less is to realize an oxide sintered body that has a high apparent density of the oxide sintered body and can reduce the surface roughness of the sputtering target during sputtering. Is advantageous. When the average aspect ratio is less than 1.5, there is a tendency that a sufficiently small surface roughness cannot be obtained. When the average aspect ratio is greater than 50, a sufficiently high apparent density tends not to be obtained.
- the average aspect ratio is more preferably 4 or more, still more preferably 6 or more, and still more preferably 8 or more. The average aspect ratio is more preferably 40 or less, and still more preferably 30 or less.
- the third crystal phase is preferably dispersed in the first crystal phase. This is advantageous when the oxide sintered body of the present embodiment is used as a sputtering target.
- the voltage applied to the sputtering target may be a DC voltage.
- the sputtering target is desired to have conductivity. This is because when the electric resistance of the sputtering target is increased, a direct-current voltage cannot be applied and film formation by sputtering (formation of an oxide semiconductor film) cannot be performed.
- the oxide sintered body used as a sputtering target there is a region with a high electrical resistance in a part thereof, and when the region is wide, a direct current voltage is not applied to the region with a high electrical resistance, so that region is not sputtered. May cause problems.
- abnormal discharge called arcing may occur in a region with high electrical resistance, which may cause problems such as film formation not being performed normally.
- the third crystal phase has a higher electric resistance than the first crystal phase, the above-described problem may occur when the third crystal phase exists over a wide region.
- the third crystal phase is preferably dispersed in the first crystal phase.
- the term “dispersion” as used herein means that the number of crystal grains having an average major axis diameter of 3 ⁇ m or more and 50 ⁇ m or less and an average aspect ratio of 1.5 or more and 50 or less is preferably 1, and at most 5 aggregates. Means it exists. Confirmation of the dispersion state can be confirmed by the reflected electron image obtained by SEM observation of 500 times as described above.
- the third crystal phase is a crystal phase different from the first crystal phase, and includes a fourth crystal phase having a second diffraction peak at a position larger than 31.77 deg of 2 ⁇ in X-ray diffraction and smaller than 32.00 deg. Is preferred.
- the inclusion of the fourth crystal phase is advantageous in realizing an oxide sintered body that has a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputter target during sputtering.
- it is advantageous in increasing the field-effect mobility and reliability under light irradiation of a semiconductor device including an oxide semiconductor film formed using an oxide sintered body as a channel layer.
- the fourth crystal phase may be the same phase as the second crystal phase.
- the fourth crystal phase is a phase that can be included in a part of the oxide sintered body.
- the position of the second diffraction peak is preferably 31 for realizing an oxide sintered body that has a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputtering target during sputtering. It is larger than .8 deg and preferably not larger than 31.96 deg.
- the fact that the second diffraction peak is observed at a position larger than 31.77 deg of 2 ⁇ and smaller than 32.00 deg in X-ray diffraction means that it has an interplanar spacing larger than 2.795 mm and smaller than 2.814 mm.
- the presence of the fourth crystal phase can be confirmed by X-ray diffraction.
- the conditions shown in the above “(2) Second crystal phase” are employed.
- In 2 O 3 (ZnO) 5 can be considered as the fourth crystal phase, but the position of the second diffraction peak indicated by the fourth crystal phase is generally more than the diffraction peak position of In 2 O 3 (ZnO) 5. Since it is in the vicinity of 31.92 deg on the low angle side, it is not certain at present whether the fourth crystal phase is actually In 2 O 3 (ZnO) 5 . When the fourth crystal phase is actually In 2 O 3 (ZnO) 5 , the fourth crystal phase and the second crystal phase are different.
- the ratio Ia / Ib between the peak intensity Ia of the first diffraction peak and the peak intensity Ib of the second diffraction peak is preferably 0.05 or more and 3 or less.
- An Ia / Ib of 0.05 or more and 3 or less realizes an oxide sintered body that has a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputtering target during sputtering. It is also advantageous for improving the field-effect mobility and reliability under light irradiation of a semiconductor device including an oxide semiconductor film formed using an oxide sintered body as a channel layer. is there.
- Ia / Ib is less than 0.05, the surface roughness of the sputtering target during sputtering tends not to be reduced. From this viewpoint, Ia / Ib is more preferably 0.1 or more, and further preferably 0.2 or more. It is not easy to prepare an oxide sintered body having Ia / Ib greater than 3. From the viewpoint of reducing the surface roughness of the sputtering target during sputtering, Ia / Ib is more preferably 2 or less.
- Ia / Ib shows a value specific to the material when the sample is non-oriented, but in the oxide sintered body of the present embodiment, Ia / Ib may show a value different from the value specific to the material. .
- the second crystal phase having the first diffraction peak and the fourth crystal phase having the second diffraction peak are the same compound, it is considered that the present compound has orientation.
- the second crystal phase having the first diffraction peak and the fourth crystal phase having the second diffraction peak are different compounds, the second crystal phase and / or the fourth crystal phase have orientation. Or a value reflecting the abundance ratio of the second crystal phase and the fourth crystal phase.
- the surface roughness of the sputter target (oxide sintered body) during sputtering may vary.
- Ia / Ib is 0.05 or more and 3 or less. This is advantageous in reducing the surface roughness of the sputtering target during sputtering.
- the third crystal phase may include a fifth crystal phase that is a crystal phase different from the first crystal phase and is a zinc tungstate compound crystal phase. Further inclusion of the fifth crystal phase is advantageous in realizing an oxide sintered body that has a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputter target during sputtering. In addition, it is advantageous in increasing the field-effect mobility and reliability under light irradiation of a semiconductor device including an oxide semiconductor film formed using an oxide sintered body as a channel layer.
- the fifth crystal phase may be the same phase as the second crystal phase or the fourth crystal phase.
- the fifth crystal phase is a phase that can be included in part of the oxide sintered body.
- the “zinc tungstate compound crystal phase” is a crystal phase mainly composed of Zn, W and O.
- a ZnWO 4 type crystal phase is mentioned.
- the "ZnWO 4 type crystal phase”, ZnWO 4 crystalline phase, and at least a portion of ZnWO 4 crystalline phase a phase that contains at least one element other than Zn and W, the same crystal structure as ZnWO 4 crystalline phase is a general term for those having The ZnWO 4 crystal phase is a zinc tungstate compound crystal phase having a crystal structure represented by the space group P12 / c1 (13) and having a crystal structure defined by JCPDS card 01-088-0251. As long as the crystal system is shown, oxygen may be deficient or metal may be dissolved, and the lattice constant may be changed.
- the presence of the fifth crystal phase can be confirmed by the presence of a peak attributed to the “zinc tungstate compound crystal phase” in X-ray diffraction.
- a peak attributed to the above-described ZnWO 4 type crystal phase As the measurement conditions for the X-ray diffraction, the conditions shown in the above “(2) Second crystal phase” are employed.
- the third crystal phase can further include a hexagonal wurtzite crystal phase. Further inclusion of a hexagonal wurtzite crystal phase is necessary for realizing an oxide sintered body that has a high apparent density even at a relatively low sintering temperature and can reduce the surface roughness of the sputter target during sputtering. It is also advantageous for increasing the field-effect mobility and reliability under light irradiation of a semiconductor device including an oxide semiconductor film formed using an oxide sintered body as a channel layer.
- the hexagonal wurtzite crystal phase may be the same phase as the fourth crystal phase. When the hexagonal wurtzite crystal phase is the fourth crystal phase, the fourth crystal phase and the second crystal phase are different.
- the hexagonal wurtzite crystal phase is a phase that can be included in part of the oxide sintered body.
- hexagonal wurtzite crystal phase refers to a hexagonal wurtz crystal phase and a phase in which at least a part of the hexagonal wurtz crystal phase contains at least one metal element other than Zn, A generic term for those having the same crystal structure as the Wurtz crystal phase.
- the hexagonal wurtz crystal phase is one of the crystal phases of zinc oxide (ZnO), and space group: P63mc, space group no. : A crystal structure represented by 186 and defined in JCPDS card 01-079-0207.
- the presence of the hexagonal wurtzite crystal phase can be confirmed by the presence of a peak attributed to the “hexagonal wurtzite crystal phase” in X-ray diffraction. For example, it can be confirmed by the presence of a peak attributed to the above zinc oxide.
- the measurement conditions for the X-ray diffraction the conditions shown in the above “(2) Second crystal phase” are employed.
- the hexagonal wurtzite crystal phase may contain ZnO as a main component, and W and / or In may be dissolved in substitutional or interstitial forms at least in part.
- W and / or In may be dissolved in substitutional or interstitial forms at least in part.
- the oxide sintered body of the present embodiment may further contain zirconium (Zr).
- the content is, for example, 1 ⁇ 10 17 atms / cm 3 or more and 1 ⁇ 10 20 atms / cm 3 or less.
- Zr is an element that can be mixed in the manufacturing process of the oxide sintered body, but it can achieve a high apparent density of the oxide sintered body and reduce the surface roughness of the sputter target during sputtering. It does not inhibit. The presence of Zr and its content can be confirmed with a secondary ion mass spectrometer.
- the oxide sintered body of the present embodiment can be suitably used as a sputter target.
- the sputter target is a raw material for the sputtering method.
- a sputtering target and a substrate are placed facing each other in a film forming chamber, a voltage is applied to the sputtering target, and the surface of the target is sputtered with rare gas ions, thereby forming atoms constituting the target from the target.
- This is a method of forming a film composed of atoms constituting the target by releasing and depositing on the substrate.
- the elements that make up the sputtering target are broken down to the atomic level by rare gas ions, but if there are protrusions on the surface, fine particles will protrude from the protrusions and enter the film, or the electric field will concentrate on the protrusions. By doing so, the number of atoms jumping out only by that portion increases, and the film thickness changes in the in-plane direction reflecting this. For this reason, if the surface of the sputtering target is rough, the thin film formed using it as a raw material may also become rough.
- the low apparent density means that there are many submicron sized pores in the sputter target.
- the same phenomenon as the above-mentioned convex portion occurs in the peripheral portion surrounding the pore, and as a result, the formed thin film may become rough.
- the formed oxide semiconductor It has been found desirable to reduce the surface roughness of the membrane.
- An oxide semiconductor film forms an interface with various films such as a gate insulating film, an etch stopper layer, a source electrode, a drain electrode, and a passivation film. If the interface is uneven, movement of electrons is hindered. It is considered that the field effect mobility is lowered. Various defect levels are likely to be generated at the above-mentioned interface, but the area of the interface increases as the surface roughness increases, and as a result, the number of defects increases, resulting in excitation of carriers under light irradiation. It is considered that the loss easily occurs and the reliability under light irradiation deteriorates.
- the oxide sintered body of this embodiment is applied to a sputter target, the surface roughness of the sputter target during sputtering can be reduced. As a result, the surface roughness of the oxide semiconductor film to be formed can be reduced. can do.
- the oxide sintered body of the present embodiment includes a predetermined second crystal phase, and has an appropriate W content, Zn content, and Zn / W ratio, so that the surface roughness of the sputter target during sputtering is high. Is an oxide sintered body that meets the above requirements.
- One method for producing an oxide sintered body according to this embodiment is a method for producing an oxide sintered body according to Embodiment 1, in which a primary mixture of zinc oxide powder and tungsten oxide powder is used.
- a step of preparing, a step of forming a calcined powder by heat-treating the primary mixture, a step of preparing a secondary mixture of raw material powders including the calcined powder, and a molded body by molding the secondary mixture A step of forming, and a step of forming an oxide sintered body by sintering the formed body.
- the primary mixture is heat-treated at a temperature of 550 ° C. or higher and lower than 1200 ° C. in an oxygen-containing atmosphere, thereby forming a double oxide powder containing Zn and W as the calcined powder. Including that.
- the primary mixture of the zinc oxide powder and the tungsten oxide powder is heat-treated at a temperature of 550 ° C. or more and less than 1200 ° C. in an oxygen-containing atmosphere.
- a double oxide powder containing Zn and W as the calcined powder increases the apparent density even at a relatively low sintering temperature and reduces the surface roughness of the sputter target during sputtering.
- An oxide sintered body that can be suitably used as a sputtering target can be obtained.
- the double oxide may be deficient in oxygen or substituted with metal.
- the temperature of the heat treatment is less than 550 ° C., a double oxide powder containing Zn and W cannot be obtained, and if it is 1200 ° C. or higher, the double oxide powder containing Zn and W is decomposed or scattered. The particle size of the double oxide powder tends to be too large for use.
- an oxide semiconductor film formed using a sputter target containing an oxide sintered body obtained is formed into a channel layer.
- the field effect mobility and the reliability under light irradiation can be increased more effectively.
- the double oxide containing Zn and W preferably contains a ZnWO 4 type crystal phase.
- the ZnWO 4 type crystal phase is a zinc tungstate compound crystal phase having a crystal structure represented by the space group P12 / c1 (13) and having a crystal structure defined by JCPDS card 01-088-0251. . As long as the crystal system is shown, oxygen may be deficient or metal may be dissolved, and the lattice constant may be changed.
- the ZnWO type 4 crystal phase is identified by X-ray diffraction measurement.
- another one of the manufacturing methods of the oxide sintered compact which concerns on this embodiment is a manufacturing method of the oxide sintered compact which concerns on Embodiment 1, Comprising: Indium oxide powder and tungsten oxide powder
- a step of preparing a primary mixture, a step of forming a calcined powder by heat-treating the primary mixture, a step of preparing a secondary mixture of raw material powders including the calcined powder, and forming the secondary mixture The step of forming a molded body by the above and the step of forming an oxide sintered body by sintering the molded body are included.
- the primary mixture is heat-treated at a temperature of 700 ° C. or higher and lower than 1400 ° C. in an oxygen-containing atmosphere, thereby forming a double oxide powder containing In and W as the calcined powder. Including that.
- the primary mixture of the indium oxide powder and the tungsten oxide powder is heat-treated at a temperature of 700 ° C. or higher and lower than 1400 ° C. in an oxygen-containing atmosphere.
- a double oxide powder containing In and W as the calcined powder increases the apparent density even at a relatively low sintering temperature, and reduces the surface roughness of the sputter target during sputtering.
- An oxide sintered body that can be suitably used as a sputtering target can be obtained.
- the double oxide may be deficient in oxygen or substituted with metal.
- the heat treatment temperature is less than 700 ° C., a double oxide powder containing In and W cannot be obtained. If the heat treatment temperature is 1400 ° C. or higher, the double oxide powder containing In and W is decomposed or scattered. The particle size of the double oxide powder tends to be too large for use.
- an oxide semiconductor film formed using a sputter target containing an oxide sintered body obtained is formed into a channel layer.
- the field effect mobility and the reliability under light irradiation can be increased more effectively.
- the double oxide containing In and W preferably contains an In 6 WO 12 type crystal phase.
- the In 6 WO 12 crystal phase is a trigonal crystal structure and is an indium tungstate compound crystal phase having a crystal structure defined by JCPDS card 01-074-1410. As long as the crystal system is shown, oxygen may be deficient or metal may be dissolved, and the lattice constant may be changed.
- 2004-091265 is an InW 3 O 9 crystal phase, has a hexagonal crystal structure, and is defined in JCPDS Card 33-627. Therefore, the crystal structure is different from the In 6 WO 12 crystal phase.
- the In 6 WO 12 type crystal phase is identified by X-ray diffraction measurement.
- the oxide sintered body containing In, W and Zn it is effective to have a double oxide containing Zn and W having a low melting point present during sintering.
- a process for producing a pre-synthesized composite oxide powder containing Zn and W It is preferable to use a method for increasing the number of contact points with Zn by using a composite oxide powder containing In and W synthesized in advance. These methods may be used alone or in combination. For example, a method of using a composite oxide powder containing Zn and W synthesized in advance in a manufacturing process and a method using a composite oxide powder containing indium and tungsten synthesized beforehand may be used in combination.
- a composite oxide powder containing Zn and W synthesized in advance is used in the manufacturing process. It is more preferable to use at least the method used.
- the tungsten oxide powder used for manufacturing the oxide sintered body preferably contains at least one crystal phase selected from the group consisting of a WO 3 crystal phase, a WO 2 crystal phase, and a WO 2.72 crystal phase. .
- the apparent density of the oxide sintered body can be increased more effectively, and the surface roughness of the sputtering target during sputtering can be reduced more effectively.
- the tungsten oxide powder preferably has a median particle diameter d50 of 0.1 ⁇ m to 4 ⁇ m, more preferably 0.2 ⁇ m to 2 ⁇ m, and further preferably 0.3 ⁇ m to 1.5 ⁇ m. preferable. Thereby, the apparent density of the oxide sintered body can be increased more effectively, and the surface roughness of the sputtering target during sputtering can be reduced more effectively.
- the median particle size d50 is determined by BET specific surface area measurement. When the median particle size d50 is smaller than 0.1 ⁇ m, it is difficult to handle the powder, and it tends to be difficult to uniformly mix the zinc oxide powder and the tungsten oxide powder or the indium oxide powder and the tungsten oxide powder. .
- the mixed oxide powder containing Zn and W obtained by heat treatment at a temperature of 550 ° C. or more and less than 1200 ° C. in an oxygen-containing atmosphere after mixing with the zinc oxide powder The particle size also increases, and it tends to be difficult to increase the apparent density of the oxide sintered body more effectively and to reduce the surface roughness of the sputtering target during sputtering more effectively.
- the particle size of the double oxide powder containing In and W obtained by heat treatment at a temperature of 700 ° C. or higher and lower than 1400 ° C. in an oxygen-containing atmosphere after being mixed with the indium oxide powder is also increased. Therefore, it tends to be difficult to increase the apparent density of the oxide sintered body more effectively and to reduce the surface roughness of the sputtering target during sputtering more effectively.
- the manufacturing method of the oxide sintered body according to the present embodiment is not particularly limited, but includes, for example, the following steps from the viewpoint of efficiently forming the oxide sintered body of Embodiment 1.
- Step of preparing raw material powder As the raw material powder of the oxide sintered body, indium oxide powder (for example, In 2 O 3 powder), tungsten oxide powder (for example, WO 3 powder, WO 2.72 powder, WO 2 Powder), zinc oxide powder (for example, ZnO powder) and the like, and oxide powders of metal elements constituting the oxide sintered body are prepared.
- As the tungsten oxide powder not only the WO 3 powder but also a powder having a chemical composition deficient in oxygen compared to the WO 3 powder such as the WO 2.72 powder and the WO 2 powder is used as a raw material. It is preferable from the viewpoint of increasing the field effect mobility and the reliability under light irradiation.
- the purity of the raw material powder is preferably a high purity of 99.9% by mass or more from the viewpoint of preventing unintentional mixing of metal elements and Si into the oxide sintered body and obtaining stable physical properties.
- the median particle diameter d50 of the tungsten oxide powder is 0.1 ⁇ m or more and 4 ⁇ m or less, the apparent density of the oxide sintered body can be increased more effectively, and the surface of the sputter target during sputtering From the viewpoint of more effectively reducing the roughness, it is preferable.
- Step of preparing primary mixture (2-1) Step of preparing primary mixture of zinc oxide powder and tungsten oxide powder Among the above raw material powders, zinc oxide powder and tungsten oxide powder Mix (or pulverize and mix). At this time, when it is desired to obtain a ZnWO 4 type crystal phase as the crystal phase of the oxide sintered body, the tungsten oxide powder and the zinc oxide powder are mixed at a molar ratio of 1: 1 to Zn 2 W 3 O 8. In order to obtain a type crystal phase, the tungsten oxide powder and the zinc oxide powder are mixed at a molar ratio of 3: 2.
- the oxide sintered body preferably contains a ZnWO 4 type phase.
- the method of mixing the tungsten oxide powder and the zinc oxide powder there is no particular limitation on the method of mixing the tungsten oxide powder and the zinc oxide powder, and any of dry and wet methods may be used, and specifically, pulverized and mixed using a ball mill, a planetary ball mill, a bead mill or the like. Is done. In this way, a primary mixture of raw material powders is obtained.
- a drying method such as natural drying or a spray dryer can be used to dry the mixture obtained using the wet pulverization and mixing method.
- Step of preparing a primary mixture of indium oxide powder and tungsten oxide powder Among the raw material powders, indium oxide powder and tungsten oxide powder are mixed (or ground and mixed). At this time, when an In 6 WO 12 type crystal phase is desired as the crystal phase of the oxide sintered body, the tungsten oxide powder and the indium oxide powder are mixed at a molar ratio of 1: 3.
- the method of mixing the tungsten oxide powder and the indium oxide powder and any of dry and wet methods may be used. Specifically, pulverized and mixed using a ball mill, a planetary ball mill, a bead mill or the like. Is done. In this way, a primary mixture of raw material powders is obtained.
- a drying method such as natural drying or a spray dryer can be used to dry the mixture obtained using the wet pulverization and mixing method.
- Step of forming calcined powder (3-1) Step of forming calcined powder of zinc tungstate oxide
- the obtained primary mixture is heat-treated (calcined) to obtain calcined powder (Zn and W A double oxide powder).
- the calcining temperature of the primary mixture is such that the particle size of the calcined product does not become too large to reduce the apparent density of the oxide sintered body and to increase the surface roughness of the sputter target during sputtering.
- it is preferably 550 ° C. or higher. .
- the calcining atmosphere may be an atmosphere containing oxygen, but may be an air atmosphere having a pressure higher than atmospheric pressure or air, or an oxygen-nitrogen mixed atmosphere containing 25% by volume or more of oxygen having a pressure higher than atmospheric pressure or air. preferable. Since the productivity is high, an air atmosphere at atmospheric pressure or in the vicinity thereof is more preferable.
- Step of forming a calcined powder of indium tungstate oxide The obtained primary mixture is heat-treated (calcined) to form a calcined powder (a double oxide powder containing In and W). To do.
- the calcining temperature of the primary mixture is such that the particle size of the calcined product does not become too large to reduce the apparent density of the oxide sintered body and to increase the surface roughness of the sputter target during sputtering.
- the temperature should be 700 ° C. or higher. Is preferred. More preferably, it is 800 degreeC or more and less than 1300 degreeC.
- the calcining atmosphere may be an atmosphere containing oxygen, but may be an air atmosphere having a pressure higher than atmospheric pressure or air, or an oxygen-nitrogen mixed atmosphere containing 25% by volume or more of oxygen having a pressure higher than atmospheric pressure or air. preferable. Since the productivity is high, an air atmosphere at atmospheric pressure or in the vicinity thereof is more preferable.
- Step of preparing secondary mixture of raw material powder including calcined powder the obtained calcined powder and the remaining powder of the raw material powder [indium oxide powder (for example, In 2 O 3 powder) ) Or zinc oxide powder (for example, ZnO powder)] is mixed (or ground and mixed) in the same manner as the preparation of the primary mixture. In this way, a secondary mixture of raw material powders is obtained.
- the tungsten oxide is preferably present as a double oxide by the calcination step.
- the obtained molded body is sintered to form an oxide sintered body.
- the hot press sintering method it is preferable not to use the hot press sintering method in terms of productivity.
- the sintering temperature of the molded body is 900 ° C. or higher. It is preferably lower than 1200 ° C.
- the sintering atmosphere from the viewpoint of obtaining an oxide sintered body having a small surface roughness of the sputtering target during sputtering by preventing the grain size of the constituent crystals of the oxide sintered body from increasing.
- An air atmosphere at or near atmospheric pressure is preferred.
- the sputter target according to the present embodiment includes the oxide sintered body according to the first embodiment. Therefore, the sputter target according to this embodiment can be suitably used for forming an oxide semiconductor film of a semiconductor device having high field effect mobility and high reliability under light irradiation by a sputtering method.
- the sputter target according to the present embodiment is preferably used for forming an oxide semiconductor film of a semiconductor device with high field effect mobility and high reliability under light irradiation by a sputtering method.
- 1 oxide sintered body is preferable, and the oxide sintered body of Embodiment 1 is more preferable.
- the semiconductor device 10 according to the present embodiment is formed using the oxide sintered body of the first embodiment or formed by sputtering using the sputter target of the third embodiment.
- the oxide semiconductor film 14 is included. Since the oxide semiconductor film 14 is included, the semiconductor device according to the present embodiment can have characteristics of high field effect mobility and high reliability under light irradiation.
- the semiconductor device 10 according to the present embodiment is not particularly limited, but is preferably a TFT (thin film transistor) because it has high field effect mobility and high reliability under light irradiation, for example.
- the oxide semiconductor film 14 included in the TFT is preferably a channel layer because it has high field-effect mobility and high reliability under light irradiation.
- the W content of the oxide semiconductor film 14 is preferably greater than 0.01 atomic% and equal to or less than 5.0 atomic%, and the Zn content of the oxide semiconductor film 14 is Preferably, it is 1.2 atomic% or more and less than 50 atomic%, and the Zn / W ratio of the oxide semiconductor film 14 is preferably larger than 1.0 and smaller than 20000.
- the field effect mobility of the semiconductor device 10 and the reliability under light irradiation can be improved.
- the W content of the oxide semiconductor film 14 is more preferably 0.05 atomic percent or more and 3 atomic percent or less, and further preferably 2 atomic percent. It is as follows. When the W content of the oxide semiconductor film 14 is 0.01 atomic% or less, in a semiconductor device including the oxide semiconductor film 14 as a channel layer, reliability under light irradiation tends to be low. When the W content of the oxide semiconductor film 14 exceeds 5.0 atomic%, the field effect mobility tends to be low in a semiconductor device including the oxide semiconductor film as a channel layer.
- the W content of the oxide semiconductor film 14 is greater than 0.01 atomic% and equal to or less than 5.0 atomic%, preferably 0.01 atomic%. More than 3 atomic%, more preferably more than 0.01 atomic% and not more than 1 atomic%, still more preferably less than 0.5 atomic%. When the W content is in the above range, the oxide semiconductor film 14 having a small surface roughness is easily obtained.
- the oxide semiconductor film 14 has a Zn content of 1.2 atomic% or more and less than 50 atomic% and the oxide semiconductor film 14 has a Zn / W ratio of greater than 1.0 and less than 20000, the oxide semiconductor film In a semiconductor device including 14 as a channel layer, field effect mobility can be increased and reliability under light irradiation can be increased.
- the Zn content of the oxide semiconductor film 14 is more preferably greater than 3 atomic percent and not greater than 40 atomic percent, and even more preferably not less than 5 atomic percent. Is less than 20 atomic%, still more preferably 11 atomic% or more, and particularly preferably 15 atomic% or more.
- the Zn content of the oxide semiconductor film 14 is smaller than 1.2 atomic%, in a semiconductor device including the oxide semiconductor film 14 as a channel layer, reliability under light irradiation tends to be low.
- the Zn content of the oxide semiconductor film 14 is 50 atomic% or more, the field effect mobility tends to be low in a semiconductor device including the oxide semiconductor film 14 as a channel layer.
- the Zn / W ratio in the oxide semiconductor film 14 is 1.0 or less, in a semiconductor device including the oxide semiconductor film 14 as a channel layer, the reliability under light irradiation tends to be low.
- the Zn / W ratio is more preferably 3.0 or more, and further preferably 5.0 or more.
- the Zn / W ratio in the oxide semiconductor film 14 is 20000 or more, the field effect mobility tends to be low in a semiconductor device including the oxide semiconductor film 14 as a channel layer.
- the Zn / W ratio is more preferably less than 100.
- the chemical composition of the oxide semiconductor film 14, that is, the content of various elements is measured by RBS (Rutherford backscattering analysis). Based on this measurement result, W content rate, Zn content rate, and Zn / W ratio are calculated.
- RBS Rutherford backscattering analysis
- W content rate, Zn content rate, and Zn / W ratio are calculated.
- TEM-EDX a transmission electron microscope with an energy dispersive fluorescent X-ray analyzer.
- RBS measurement is desirable because of the accuracy of chemical composition measurement.
- TEM-EDX first, a calibration curve sample is made of In, W, Zn, and O, has a composition close to the oxide semiconductor film to be measured, and can be analyzed by RBS At least three or more oxide semiconductor films are prepared.
- the contents of In, W and Zn are measured by RBS, and the contents of In, W and Zn are measured by TEM-EDX. From these measured values, a calibration curve showing the relationship between the measured values of In, W and Zn contents by TEM-EDX and the measured values of In, W and Zn contents by RBS is created. Then, for the oxide semiconductor film to be measured, the contents of In, W and Zn are measured by TEM-EDX, and then the measured values are measured for the contents of In, W and Zn by RBS based on the calibration curve. Convert to value. This converted value is the content of In, W, and Zn in the oxide semiconductor film to be measured.
- the oxide semiconductor 14 may further contain zirconium (Zr).
- the content is, for example, 1 ⁇ 10 17 atms / cm 3 or more and 1 ⁇ 10 20 atms / cm 3 or less.
- Zr is an element that can be mixed in the manufacturing process of the oxide sintered body, and can also be mixed in the oxide semiconductor film 14 formed using this oxide sintered body as a raw material. It does not hinder high field effect mobility and high reliability under light irradiation. The presence and content of zirconium can be confirmed with a secondary ion mass spectrometer.
- the oxide semiconductor film 14 is composed of at least one of a nanocrystalline oxide and an amorphous oxide, and has a high field effect mobility in a semiconductor device (for example, TFT) including this as a channel layer, and This is preferable from the viewpoint that reliability under light irradiation can be increased.
- a semiconductor device for example, TFT
- the “nanocrystalline oxide” means that only a broad peak appearing on a low angle side called a halo is observed without observing a peak due to a crystal even by X-ray diffraction measurement according to the following conditions.
- region is implemented according to the following conditions using a transmission electron microscope, the ring-shaped pattern is observed.
- the ring-shaped pattern includes a case where spots are gathered to form a ring-shaped pattern.
- amorphous oxide means that only a broad peak appearing on the low angle side called a halo is observed without a peak due to a crystal being observed even by X-ray diffraction measurement under the following conditions.
- Measuring method Micro electron diffraction method, Acceleration voltage: 200 kV, Beam diameter: Same or equivalent to the thickness of the oxide semiconductor film to be measured.
- an oxide semiconductor film as disclosed in, for example, Japanese Patent No. 5172918 includes c-axis-oriented crystals along a direction perpendicular to the surface of the film. When the nanocrystals in the region are oriented in a certain direction, a spot-like pattern is observed.
- the nanocrystal has a crystal with respect to the surface of the film when at least a plane (film cross section) perpendicular to the film plane is observed. It is non-oriented and has random orientation. That is, the crystal axis is not oriented with respect to the film thickness direction.
- the oxide semiconductor film 14 is composed of nanocrystalline oxide or amorphous oxide, high field effect mobility can be achieved in a semiconductor device including the oxide semiconductor film 14 as a channel layer.
- the oxide semiconductor film 14 is preferably made of an amorphous oxide.
- the film thickness of the oxide semiconductor film 14 is, for example, not less than 2 nm and not more than 60 nm.
- the oxide semiconductor film 14 preferably has an electrical resistivity of 10 ⁇ 1 ⁇ cm or more.
- the electrical resistivity is required to be smaller than 10 ⁇ 1 ⁇ cm.
- the oxide semiconductor film included in the semiconductor device of this embodiment preferably has an electric resistivity of 10 ⁇ 1 ⁇ cm or more, and thus can be suitably used as a channel layer of the semiconductor device.
- the electrical resistivity is smaller than 10 ⁇ 1 ⁇ cm, it is difficult to use as a channel layer of a semiconductor device.
- the oxide semiconductor film 14 can be obtained by a manufacturing method including a step of forming a film by a sputtering method.
- the meaning of the sputtering method is as described above.
- a method for forming the oxide semiconductor film a pulse laser deposition (PLD) method, a heating deposition method, and the like have been proposed in addition to the sputtering method.
- PLD pulse laser deposition
- the sputtering method is preferable from the viewpoint of productivity.
- a magnetron sputtering method As the sputtering method, a magnetron sputtering method, a counter target type magnetron sputtering method, or the like can be used.
- Ar gas, Kr gas, and Xe gas can be used as the atmosphere gas at the time of sputtering, and oxygen gas can be mixed and used with these gases.
- the oxide semiconductor film 14 can also be obtained by heat treatment after film formation by sputtering, or by heat treatment while film formation by sputtering. Accordingly, an oxide semiconductor film composed of nanocrystalline oxide or amorphous oxide can be easily obtained. In addition, an oxide semiconductor film obtained by this method is advantageous in increasing field-effect mobility and reliability under light irradiation in a semiconductor device (eg, TFT) including the oxide semiconductor film as a channel layer.
- a semiconductor device eg, TFT
- the heat treatment that is performed while performing film formation by sputtering can be performed by heating the substrate during the film formation.
- the substrate temperature is preferably 100 ° C. or higher and 250 ° C. or lower.
- the heat treatment time corresponds to the film formation time, and the film formation time depends on the thickness of the oxide semiconductor film 14 to be formed, but can be, for example, about 10 seconds to 10 minutes.
- the heat treatment performed after the film formation by the sputtering method can be performed by heating the substrate.
- heat treatment is preferably performed after film formation by sputtering.
- heat treatment may be performed immediately after the oxide semiconductor film 14 is formed, or heat treatment may be performed after the source electrode, the drain electrode, the etch stopper layer (ES layer), the passivation layer, and the like are formed. .
- the substrate temperature is preferably 100 ° C. or higher and 500 ° C. or lower.
- the atmosphere of the heat treatment may be various atmospheres such as air, nitrogen gas, nitrogen gas-oxygen gas, Ar gas, Ar-oxygen gas, water vapor-containing air, water vapor-containing nitrogen.
- the atmospheric pressure can be atmospheric pressure, reduced pressure conditions (for example, less than 0.1 Pa), and pressurized conditions (for example, 0.1 Pa to 9 MPa), but is preferably atmospheric pressure.
- the heat treatment time can be, for example, about 3 minutes to 2 hours, and preferably about 10 minutes to 90 minutes.
- 1A, 1B, 2 and 3 are schematic views showing some examples of a semiconductor device (TFT) according to this embodiment.
- 1A and 1B includes a substrate 11, a gate electrode 12 disposed on the substrate 11, a gate insulating film 13 disposed as an insulating layer on the gate electrode 12, and a gate insulating film 13 It includes an oxide semiconductor film 14 disposed as a channel layer thereon, and a source electrode 15 and a drain electrode 16 disposed on the oxide semiconductor film 14 so as not to contact each other.
- the semiconductor device 20 shown in FIG. 2 is disposed on the gate insulating film 13 and the oxide semiconductor film 14, and is disposed on the etch stopper layer 17, the etch stopper layer 17, the source electrode 15 and the drain electrode 16 having contact holes.
- the semiconductor device 10 has the same configuration as that of the semiconductor device 10 shown in FIGS. 1A and 1B except that the passivation film 18 is further included.
- the passivation film 18 may be omitted as in the semiconductor device 10 shown in FIGS. 1A and 1B.
- the semiconductor device 30 shown in FIG. 3 is the same as the semiconductor device 10 shown in FIGS. 1A and 1B, except that it further includes a passivation film 18 disposed on the gate insulating film 13, the source electrode 15, and the drain electrode 16. It has the composition of.
- a semiconductor device includes the oxide semiconductor film 14 and is a layer disposed in contact with at least a part of the oxide semiconductor film 14 and is an amorphous layer (hereinafter, referred to as “amorphous layer”). This layer is also referred to as “amorphous adjacent layer”). According to the semiconductor device including the amorphous adjacent layer, even when the temperature of the heat treatment described above is high, the oxide semiconductor film 14 can maintain a state in which the oxide semiconductor film 14 is formed of an amorphous oxide. It can be held, and high reliability under light irradiation can be realized. Examples of the amorphous adjacent layer include a gate insulating film 13, a passivation layer 18, and an etch stopper layer 17.
- the amorphous adjacent layer may be a layer formed in contact with the oxide semiconductor film 14 as a base (lower layer) of the oxide semiconductor film 14 or may be an upper layer formed in contact with the oxide semiconductor film 14. There may be.
- the semiconductor device according to the present embodiment can include two or more adjacent layers. In this case, these adjacent layers can be a lower layer and an upper layer of the oxide semiconductor film 14.
- the gate insulating film 13 may be an amorphous adjacent layer.
- the gate insulating film 13 and / or the etch stopper layer 17 may be an amorphous adjacent layer.
- the gate insulating film 13 and / or the passivation film 18 may be an amorphous adjacent layer.
- the amorphous adjacent layer is preferably an oxide layer containing at least one of silicon and aluminum.
- the fact that the amorphous adjacent layer is an oxide layer containing at least one of silicon and aluminum is advantageous in increasing the field effect mobility of the semiconductor device and the reliability under light irradiation. Even when the temperature of the heat treatment is high, it is advantageous in providing a semiconductor device capable of maintaining high field effect mobility.
- the amorphous adjacent layer being an oxide layer containing at least one of silicon and aluminum can be advantageous in reducing the OFF current.
- the oxide containing at least one of silicon and aluminum is not particularly limited, and examples thereof include silicon oxide (SiO x ) and aluminum oxide (Al m O n ).
- a method for manufacturing a semiconductor device includes a step of preparing the sputter target of the above embodiment and a step of forming the oxide semiconductor film by a sputtering method using the sputter target.
- FIGS. 4A to 4D are illustrated from the viewpoint of efficiently manufacturing a high-performance semiconductor device 10. Referring to FIG. 4A, a step of forming gate electrode 12 on substrate 11, a step of forming gate insulating film 13 as an insulating layer on gate electrode 12 and substrate 11 (FIG. 4B), and gate insulating film 13.
- a step of forming the oxide semiconductor film 14 as a channel layer thereon (FIG. 4C), and a step of forming the source electrode 15 and the drain electrode 16 on the oxide semiconductor film 14 so as not to contact each other (FIG. 4D). It is preferable to include.
- gate electrode 12 is formed on substrate 11.
- the substrate 11 is not particularly limited, but is preferably a quartz glass substrate, an alkali-free glass substrate, an alkali glass substrate, or the like from the viewpoint of increasing transparency, price stability, and surface smoothness.
- the gate electrode 12 is not particularly limited, but is preferably a Mo electrode, a Ti electrode, a W electrode, an Al electrode, a Cu electrode, or the like because it has high oxidation resistance and low electrical resistance.
- the method for forming the gate electrode 12 is not particularly limited, but is preferably a vacuum deposition method, a sputtering method, or the like because it can be uniformly formed on the main surface of the substrate 11 with a large area. As shown in FIG. 4A, when the gate electrode 12 is partially formed on the surface of the substrate 11, an etching method using a photoresist can be used.
- gate insulating film 13 is formed as an insulating layer on gate electrode 12 and substrate 11.
- the method for forming the gate insulating film 13 is not particularly limited, but is preferably a plasma CVD (chemical vapor deposition) method or the like from the viewpoint of being able to be uniformly formed in a large area and ensuring insulation.
- the material of the gate insulating film 13 is not particularly limited, but is preferably silicon oxide (SiO x ), silicon nitride (SiN y ) or the like from the viewpoint of insulation. Further, when the gate insulating film 13 is the above-described amorphous adjacent layer, the gate insulating film 13 may be an oxide containing at least one of silicon and aluminum such as silicon oxide (SiO x ) and aluminum oxide (Al m O n ). preferable.
- an oxide semiconductor film 14 is formed as a channel layer on the gate insulating film 13.
- the oxide semiconductor film 14 is preferably formed including a step of forming a film by sputtering.
- heat treatment is performed after film formation by sputtering, or while film formation is performed by sputtering. It is preferably formed by heat treatment.
- the raw material target (sputter target) of the sputtering method the oxide sintered body of the first embodiment is used.
- heat treatment may be performed immediately after the oxide semiconductor film 14 is formed, or heat treatment may be performed after the source electrode 15, the drain electrode 16, the etch stopper layer 17, the passivation layer 18, and the like are formed. .
- this heat treatment may be before or after the formation of the source electrode 15 and the drain electrode 16, but before the formation of the passivation layer 18. Is preferred.
- source electrode 15 and drain electrode 16 are formed on oxide semiconductor film 14 so as not to contact each other.
- the source electrode 15 and the drain electrode 16 are not particularly limited, but have a high oxidation resistance, a low electric resistance, and a low contact electric resistance with the oxide semiconductor film 14, so that the Mo electrode, the Ti electrode, and the W electrode Al electrode, Cu electrode and the like are preferable.
- a method for forming the source electrode 15 and the drain electrode 16 is not particularly limited, but it can be uniformly formed in a large area on the main surface of the substrate 11 on which the oxide semiconductor film 14 is formed. It is preferable that it is a law etc.
- a method for forming the source electrode 15 and the drain electrode 16 so as not to contact each other is not particularly limited, but etching using a photoresist is possible because a pattern of the source electrode 15 and the drain electrode 16 having a large area can be formed uniformly. Formation by a method is preferred.
- This manufacturing method further includes a step of forming an etch stopper layer 17 having a contact hole 17a and a step of forming a passivation film 18.
- 1A and 1B can be used.
- a gate electrode 12 on a substrate 11 can be used.
- Forming a gate insulating film 13 as an insulating layer on the gate electrode 12 and the substrate 11 (FIG. 4B), and forming an oxide semiconductor film 14 as a channel layer on the gate insulating film 13. Forming (FIG.
- etch stopper layer 17 on the oxide semiconductor film 14 and the gate insulating film 13 (FIG. 5A), A step of forming a contact hole 17a in the etch stopper layer 17 (FIG. 5B), a step of forming the source electrode 15 and the drain electrode 16 on the oxide semiconductor film 14 and the etch stopper layer 17 so as not to contact each other (FIG. 5C), It is preferable to include a step (FIG. 5D) of forming a passivation film 18 on the etch stopper layer 17, the source electrode 15 and the drain electrode 16.
- the material of the etch stopper layer 17 is not particularly limited, but is preferably silicon oxide (SiO x ), silicon nitride (SiN y ), aluminum oxide (Al m O n ) or the like from the viewpoint of insulation. Further, when the etch stopper layer 17 is the above-described amorphous adjacent layer, it may be an oxide containing at least one of silicon and aluminum such as silicon oxide (SiO x ) and aluminum oxide (Al m O n ). preferable.
- the etch stopper layer 17 may be a combination of films made of different materials.
- the method for forming the etch stopper layer 17 is not particularly limited, but from the viewpoint of being able to be uniformly formed in a large area and ensuring insulation, it is possible to use a plasma CVD (chemical vapor deposition) method, a sputtering method, a vacuum evaporation method or the like. Preferably there is.
- the contact hole 17 a is formed in the etch stopper layer 17 after the etch stopper layer 17 is formed on the oxide semiconductor film 14.
- Examples of the method for forming the contact hole 17a include dry etching or wet etching. By etching the etch stopper layer 17 by this method to form the contact hole 17a, the surface of the oxide semiconductor film 14 is exposed in the etched portion.
- the source electrode 15 and the drain are formed on the oxide semiconductor film 14 and the etch stopper layer 17 in the same manner as the manufacturing method of the semiconductor device 10 shown in FIGS. 1A and 1B.
- a passivation film 18 is formed on the etch stopper layer 17, the source electrode 15 and the drain electrode 16 (FIG. 5D).
- the material of the passivation film 18 is not particularly limited, but is preferably silicon oxide (SiO x ), silicon nitride (SiN y ), aluminum oxide (Al m O n ) or the like from the viewpoint of insulation. Further, when the passivation film 18 is the above-described amorphous adjacent layer, it is preferably an oxide including at least one of silicon and aluminum such as silicon oxide (SiO x ) and aluminum oxide (Al m O n ). .
- the passivation film 18 may be a combination of films made of different materials.
- the formation method of the passivation film 18 is not particularly limited, but is a plasma CVD (chemical vapor deposition) method, a sputtering method, a vacuum evaporation method, etc. from the viewpoint that it can be uniformly formed in a large area and to ensure insulation. It is preferable.
- a plasma CVD chemical vapor deposition
- a sputtering method a vacuum evaporation method, etc. from the viewpoint that it can be uniformly formed in a large area and to ensure insulation. It is preferable.
- the back channel etch (BCE) structure is adopted without forming the etch stopper layer 17, and the gate insulating film 13, the oxide semiconductor film 14, the source electrode 15 and the drain are formed.
- a passivation film 18 may be formed directly on the electrode 16. With respect to the passivation film 18 in this case, the above description of the passivation film 18 included in the semiconductor device 20 shown in FIG. 2 is cited.
- the heat treatment can be performed by heating the substrate.
- the substrate temperature is preferably 100 ° C. or higher and 250 ° C. or lower.
- the atmosphere of the heat treatment may be various atmospheres such as air, nitrogen gas, nitrogen gas-oxygen gas, Ar gas, Ar-oxygen gas, water vapor-containing air, water vapor-containing nitrogen.
- An inert atmosphere such as nitrogen or Ar gas is preferable.
- the atmospheric pressure can be atmospheric pressure, reduced pressure conditions (for example, less than 0.1 Pa), and pressurized conditions (for example, 0.1 Pa to 9 MPa), but is preferably atmospheric pressure.
- the heat treatment time can be, for example, about 3 minutes to 2 hours, and preferably about 10 minutes to 90 minutes.
- Example 1 to Example 22> Preparation of oxide sintered body (1-1) Preparation of powder raw material The composition and median particle size d50 (shown as “W particle size” in Table 1) shown in Table 1 and a purity of 99 .99 mass% tungsten oxide powder (indicated as “W” in Table 1) and ZnO powder having a median particle diameter d50 of 1.0 ⁇ m and a purity of 99.99 mass% (referred to as “Z” in Table 1). And an In 2 O 3 powder (denoted as “I” in Table 1) having a median particle diameter d50 of 1.0 ⁇ m and a purity of 99.99% by mass were prepared.
- the oxide sintered bodies of the examples all had a bixbite type crystal phase, a second crystal phase, and a fourth crystal phase.
- Table 2 shows the angle of the first diffraction peak of the second crystal phase and the angle of the second diffraction peak of the fourth crystal phase.
- the peak intensity IIn of the diffraction peak having the highest intensity among the diffraction peaks attributed to the bixbyite crystal phase of X-ray diffraction and the highest intensity among the diffraction peaks not attributed to the bixbite crystal phase. Since the ratio IIn / Im of the peak intensity Im of the diffraction peak was 3.0 or more, it can be said that the oxide sintered bodies of the examples are mainly composed of the bixbite type crystal phase.
- the “indium-rich crystal phase occupancy” in the oxide sintered body is defined as the ratio (percentage) of the area of the indium-rich crystal phase (group B) to the measurement surface of the oxide sintered body. .
- the indium-rich crystal phase occupation ratio was 50% or more, and the first crystal phase was the main component.
- the “identified crystal phase” column summarizes the crystal phases present in the oxide sintered body.
- the abbreviations in the table mean the following crystal phases.
- those that can be identified by the above X-ray diffraction measurement are shown (however, in the above [A] X-ray diffraction measurement).
- the identified second crystal phase and the fourth crystal phase are not shown.), Which means that the oxide sintered body is composed only of those described in the column “Identified crystal phase”. It is not a thing.
- I Bixbite type crystal phase (first crystal phase)
- ZW zinc tungstate compound crystal phase (third crystal phase and fifth crystal phase)
- IZ In 2 O 3 (ZnO) 5 (third crystal phase).
- Oxide sintered bodies were produced in the same manner as Comparative Examples 1 to 4 except that the sintering temperature was 1170 ° C.
- the apparent density of these oxide sintered bodies was 6.3 g / cm. It was 3 .
- a mixed gas of Ar (argon) gas and O 2 (oxygen) gas was introduced into the film formation chamber to a pressure of 0.5 Pa.
- the O 2 gas content in the mixed gas was 25% by volume.
- Sputtering discharge was caused by applying DC power of 250 W to the target. Sputtering was performed for 20 hours. Thereby, the processing trace on the target surface disappears, and the surface roughness during sputtering is obtained.
- the sputtering for 20 hours may be continuous or intermittent.
- the target is removed from the vacuum chamber, and the surface roughness of the sputtered target using a stylus type surface roughness meter (“Surfcom 480B” manufactured by Tokyo Seimitsu Co., Ltd.) is used to calculate the arithmetic average roughness according to JIS B 0601: 2013. Ra was measured.
- the sputtered target surface is a portion of a track-like etching mark corresponding to the magnetic field design of a magnet installed in a sputtering evaporation source called erosion.
- the measurement was performed in the direction along the track width with the center of the track width as the measurement center position and a measurement width of 0.4 mm.
- Table 2 The obtained results are shown in Table 2 as relative values when the arithmetic average roughness of Comparative Example 1 is “1”.
- TFT semiconductor device
- TFT semiconductor device
- 3-1 Fabrication and evaluation of a semiconductor device (TFT) including an oxide semiconductor film, and measurement of surface roughness of the oxide semiconductor film (3-1) Fabrication of a semiconductor device (TFT) including an oxide semiconductor film
- a TFT having a structure similar to that of the semiconductor device 30 shown in FIG. 4A first, a synthetic quartz glass substrate having a size of 50 mm ⁇ 50 mm ⁇ thickness 0.6 mm was prepared as a substrate 11, and a Mo electrode having a thickness of 100 nm was formed as a gate electrode 12 on the substrate 11 by sputtering. Next, as shown in FIG. 4A, the gate electrode 12 was formed into a predetermined shape by etching using a photoresist.
- an oxide semiconductor film 14 having a thickness of 25 nm was formed on the gate insulating film 13 by a DC (direct current) magnetron sputtering method.
- a plane having a target diameter of 3 inches (76.2 mm) was a sputter surface.
- the oxide sintered body obtained in the above (1) was used.
- the target was disposed at a distance of 60 mm so as to face the gate insulating film 13.
- the target was sputtered in the following manner with a vacuum degree of about 6 ⁇ 10 ⁇ 5 Pa in the film formation chamber.
- a mixed gas of Ar (argon) gas and O 2 (oxygen) gas was introduced into the film formation chamber up to a pressure of 0.5 Pa in a state where a shutter was put between the gate insulating film 13 and the target.
- the O 2 gas content in the mixed gas was 25% by volume.
- Sputtering discharge was caused by applying DC power of 250 W, thereby cleaning the target surface (pre-sputtering) for 5 minutes.
- the same value of DC power was applied to the same target, and the oxide semiconductor film 14 was formed on the gate insulating film 13 by removing the shutter while maintaining the atmosphere in the film formation chamber.
- the substrate holder was water-cooled or heated to adjust the temperature of the substrate 11 during and after film formation.
- the substrate temperature is set to 120 by heating the substrate holder during film formation. Heat treatment was performed simultaneously with film formation by adjusting the temperature to ° C. In this case, the heat treatment time corresponds to the film formation time.
- the substrate is heated after film formation (after formation of a passivation layer, as will be described later), and heat treatment is performed at 250 ° C. for 10 minutes or 350 ° C. for 10 minutes.
- the semiconductor device characteristics were measured.
- the substrate temperature is set to 20 by cooling the substrate holder with water during film formation. The substrate was heated after film formation (after formation of a passivation layer, as will be described later), and heat treatment was performed at 250 ° C. for 10 minutes or 350 ° C. for 10 minutes, and semiconductor device characteristics described later were measured.
- the oxide semiconductor film 14 was formed by the DC (direct current) magnetron sputtering method using the target processed from the oxide sintered body obtained in the above (1).
- the oxide semiconductor film 14 functions as a channel layer in the TFT.
- the thickness of the oxide semiconductor film 14 formed in each example and comparative example was 25 nm.
- a source electrode forming portion 14s, a drain electrode forming portion 14d, and a channel portion 14c were formed.
- the main surface size of the source electrode forming portion 14s and the drain electrode forming portion 14d is 50 ⁇ m ⁇ 50 ⁇ m, and the channel length C L (refer to FIGS. 1A and 1B, the channel length C L is the source electrode 15 is the distance of the channel portion 14c between the drain electrode 16 and the drain electrode 16.
- the channel width C W is 30 ⁇ m (refer to FIGS. 1A and 1B, the channel width C W is the width of the channel portion 14c. .) Was 40 ⁇ m.
- the channel portion 14c has 25 ⁇ 25 ⁇ 25 mm in the main surface of 75 mm ⁇ 75 mm and 25 ⁇ 25 in the main surface of the 75 mm ⁇ 75 mm so that the TFTs are arranged in the length of 25 ⁇ 25 in the main surface of 75 mm ⁇ 75 mm. Arranged.
- the substrate 11 was immersed in the etching aqueous solution at 40 ° C.
- the source electrode 15 and the drain electrode 16 were formed on the oxide semiconductor film 14 separately from each other.
- a resist (not shown) is applied on the oxide semiconductor film 14 so that only the main surfaces of the source electrode forming portion 14s and the drain electrode forming portion 14d of the oxide semiconductor film 14 are exposed. , Exposed and developed. Next, a Mo electrode having a thickness of 100 nm, which is the source electrode 15 and the drain electrode 16, respectively, was formed on the main surfaces of the source electrode forming portion 14s and the drain electrode forming portion 14d of the oxide semiconductor film 14 by sputtering. Thereafter, the resist on the oxide semiconductor film 14 was peeled off.
- Each of the Mo electrode as the source electrode 15 and the Mo electrode as the drain electrode 16 has one channel portion 14c so that the TFTs are arranged 25 ⁇ 25 ⁇ 3 mm apart at an interval of 3 mm in the main surface of the substrate of 75 mm ⁇ 75 mm. One for each.
- a passivation film 18 was formed on the gate insulating film 13, the oxide semiconductor film 14, the source electrode 15 and the drain electrode 16.
- the passivation film 18 is an amorphous oxide layer formed by forming a 200 nm thick SiO x film by a plasma CVD method and then forming a 200 nm thick SiN y film thereon by a plasma CVD method, or an amorphous oxide layer. after forming by sputtering Al m O n film of a thickness of 120 nm, and a configuration in which the SiN y film having a thickness of 200nm was formed by plasma CVD thereon.
- the amorphous oxide layer is a SiO x film
- SiO x when the amorphous oxide layer is Al m O n film, "PV layer It is described as "Al m O n” in the column of ".
- Atomic composition ratio of the SiO x film, Si: O 1: it is close oxygen content by 2
- the atomic composition ratio of Al m O n film, Al: O 2: is the oxygen content closer 3 This is desirable from the viewpoint of improving reliability under light irradiation.
- the passivation film 18 on the source electrode 15 and the drain electrode 16 was etched by reactive ion etching to form a contact hole, thereby exposing a part of the surface of the source electrode 15 and the drain electrode 16.
- heat treatment was performed in an atmospheric pressure nitrogen atmosphere. This heat treatment was performed for all the examples and comparative examples. Specifically, the heat treatment was performed at 250 ° C. for 10 minutes in a nitrogen atmosphere or at 350 ° C. for 10 minutes in a nitrogen atmosphere. Through the above steps, a TFT including the oxide semiconductor film 14 as a channel layer was obtained.
- a sputter target was produced according to (2-1) above. Subsequently, sputtering was performed for 20 hours in the same manner as in the above (2-2). Next, a 2-inch mirror surface Si wafer was set so as to face the sputter target. The target was sputtered in the following manner with a vacuum degree of about 6 ⁇ 10 ⁇ 5 Pa in the film formation chamber. With a shutter between the target and the substrate, a mixed gas of Ar (argon) gas and O 2 (oxygen) gas was introduced into the film formation chamber to a pressure of 0.5 Pa. The O 2 gas content in the mixed gas was 25% by volume. Sputtering discharge was caused by applying DC power of 250 W to the target. After holding for 10 minutes, the shutter was removed from between the substrate and the target, and an oxide semiconductor film was formed over the substrate. The deposition time was adjusted so that the thickness of the oxide semiconductor film was 2 ⁇ m.
- V gs- (I ds ) A tangent line is drawn to a 1/2 curve, and a point (x intercept) where a tangent line having a point where the inclination of the tangent line is the maximum intersects the x axis (V gs ) is defined as a threshold voltage V th . did.
- the threshold voltage V th is obtained after performing a heat treatment at 250 ° C.
- Vth is desirably 0 V or more. Further, when a TFT is used in a display device, it is desirable that Vth is closer to 1.0 V because of the same driving voltage as a-Si.
- the field effect mobility ⁇ fe after the heat treatment at 250 ° C. for 10 minutes in the atmospheric pressure nitrogen atmosphere is shown in the column of “mobility (250 ° C.)” in Table 3. Further, the field effect mobility ⁇ fe after the heat treatment at 350 ° C. for 10 minutes in the atmospheric pressure nitrogen atmosphere is shown in the column of “mobility (350 ° C.)” in Table 3. As shown in Table 3, the larger the Zn / W ratio, the smaller the difference between mobility (250 ° C.) and mobility (350 ° C.).
- the source-gate voltage V gs applied between the source electrode 15 and the gate electrode 12 is fixed to ⁇ 25V while irradiating light with a wavelength of 460 nm from the upper part of the TFT at an intensity of 0.3 mW / cm 2 .
- the voltage was continuously applied for 1 hour. 1s from application start, 10s, 100s, 300s, determine the threshold voltage V th to the above-described method after 3600s, it was determined the difference [Delta] V th between the maximum threshold voltage V th and the minimum threshold voltage V th. It is determined that the smaller the ⁇ V th is, the higher the reliability under light irradiation is.
- ⁇ V th after the heat treatment at 250 ° C. for 10 minutes in the atmospheric pressure nitrogen atmosphere is shown in the column of “ ⁇ V th (250 ° C.)” in Table 3. Further, ⁇ V th after the heat treatment at 350 ° C. for 10 minutes in the atmospheric pressure nitrogen atmosphere is shown in the column of “ ⁇ V th (350 ° C.)” in Table 3. Note that the semiconductor device of Comparative Example 1 could not be driven as a TFT.
- TFT Semiconductor device
- 11 substrate 12 gate electrode, 13 gate insulating film, 14 oxide semiconductor film, 14c channel part, 14d drain electrode forming part, 14s source electrode forming part, 15 source electrode 16 drain electrode, 17 etch stopper layer, 17a contact hole, 18 passivation film.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Organic Chemistry (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Physics & Mathematics (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Computer Hardware Design (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Structural Engineering (AREA)
- Inorganic Chemistry (AREA)
- Thermal Sciences (AREA)
- Optics & Photonics (AREA)
- Physical Vapour Deposition (AREA)
- Thin Film Transistor (AREA)
- Physical Deposition Of Substances That Are Components Of Semiconductor Devices (AREA)
Abstract
Description
本発明のさらに別の態様に係る半導体デバイスの製造方法は、酸化物半導体膜を含む半導体デバイスの製造方法であって、上記態様のスパッタターゲットを用意する工程と、スパッタターゲットを用いてスパッタ法により酸化物半導体膜を形成する工程とを含む。
特許文献1に記載のIGZO系酸化物半導体膜をチャネル層として含むTFTは、電界効果移動度が10cm2/Vs程度と低いことが課題である。
上記によれば、比較的低い焼結温度でも高い見かけ密度を示すことができるとともに、スパッタターゲットに適用したときに、スパッタ中のスパッタターゲットの表面粗さを小さくすることができる酸化物焼結体およびその製造方法を提供することができる。また上記によれば、高電界効果移動度と光照射下での高信頼性とを両立できる半導体デバイスを提供することが可能である。
まず、本発明の実施形態を列記して説明する。
[実施形態1:酸化物焼結体]
本実施形態の酸化物焼結体は、インジウム(In)、タングステン(W)および亜鉛(Zn)を含有する酸化物焼結体である。本実施形態の酸化物焼結体は、該酸化物焼結体の主成分であってビックスバイト型結晶相を含む第1結晶相と、X線回折における2θの34.74degより大きく34.97degより小さい位置に第1回折ピークを有する第2結晶相とを含む。第2結晶相は、酸化物焼結体の一部に含まれる。本実施形態の酸化物焼結体は、見かけ密度が6.4g/cm3より大きく7.5g/cm3以下であり、W含有率が0.01原子%より大きく5.0原子%以下であり、Zn含有率が1.2原子%以上50原子%未満であり、Zn/W比が1.0より大きく20000より小さい。
第1結晶相は、酸化物焼結体の主成分であり、少なくともビックスバイト型結晶相を含む、後述するインジウム高含有型結晶相である。本明細書において「ビックスバイト型結晶相」とは、ビックスバイト結晶相、ならびにビックスバイト結晶相の少なくとも一部にIn以外の金属元素の少なくとも1つが含まれる相であって、ビックスバイト結晶相と同じ結晶構造を有するものの総称をいう。ビックスバイト結晶相は、インジウム酸化物(In2O3)の結晶相の1つであり、JCPDSカードの6-0416に規定される結晶構造をいい、希土類酸化物C型相(またはC-希土構造相)とも呼ぶ。
第2結晶相は、第1結晶相とは異なる結晶相であって、X線回折における2θの34.74degより大きく34.97degより小さい位置に第1回折ピークを有する結晶相である。第1結晶相とともに、これとは異なる第2結晶相を含む本実施形態の酸化物焼結体は、比較的低い焼結温度でも高い見かけ密度を示すことができるとともに、スパッタ中のスパッタターゲットの表面粗さを小さくすることができる。第1回折ピークの位置は、見かけ密度およびスパッタ中のスパッタターゲットの表面粗さを小さくする観点から、好ましくは2θの34.90degよりも小さい。第2結晶相は、酸化物焼結体の一部に含まれる。
θ-2θ法、
X線源:Cu Kα線、
X線管球電圧:45kV、
X線管球電流:40mA、
ステップ幅:0.03deg、
ステップ時間:1秒/ステップ、
測定範囲2θ:10deg~90deg。
本実施形態の酸化物焼結体は、見かけ密度が6.4g/cm3より大きく7.5g/cm3以下である。また本実施形態の酸化物焼結体は、その理論密度に対する見かけ密度の比である相対密度(相対密度/理論密度)が94%以上であることが好ましい。本実施形態の酸化物焼結体の理論密度は、そのIn含有率、W含有率およびZn含有率に依存し、計算上、6.8g/cm3~7.5g/cm3の範囲の値を採り得る。
本実施形態の酸化物焼結体は、第1結晶相とは異なる結晶相であって、亜鉛(Zn)を含有する第3結晶相を含むことが好ましい。第3結晶相を含むことは、比較的低い焼結温度でも見かけ密度が高く、かつスパッタ中のスパッタターゲットの表面粗さを小さくすることができる酸化物焼結体を実現するうえで有利であり、また、酸化物焼結体を用いて形成される酸化物半導体膜をチャネル層として含む半導体デバイスの電界効果移動度および光照射下での信頼性を高めるうえでも有利である。第3結晶相は、第2結晶相と同じ相である場合もあり得る。第3結晶相は、酸化物焼結体の一部に含まれ得る相である。
Ia=Ia’-Iave
より求める。同様に、第2回折ピークのピーク強度Ibを、下記式:
Ib=Ib’-Iave
より求める。本計算はX線回折におけるバックグラウンドを除去することを目的としている。
本実施形態の酸化物焼結体は、スパッタターゲットとして好適に用いることができる。スパッタターゲットとは、スパッタ法の原料となるものである。スパッタ法とは、成膜室内にスパッタターゲットと基板とを対向させて配置し、スパッタターゲットに電圧を印加して、希ガスイオンでターゲットの表面をスパッタリングすることにより、ターゲットからターゲットを構成する原子を放出させて基板上に堆積させることによりターゲットを構成する原子で構成される膜を形成する方法をいう。
本実施形態に係る酸化物焼結体の製造方法の1つは、実施形態1に係る酸化物焼結体の製造方法であって、亜鉛酸化物粉末とタングステン酸化物粉末との1次混合物を調製する工程と、1次混合物を熱処理することにより仮焼粉末を形成する工程と、仮焼粉末を含む原料粉末の2次混合物を調製する工程と、2次混合物を成形することにより成形体を形成する工程と、成形体を焼結することにより酸化物焼結体を形成する工程とを含む。仮焼粉末を形成する工程は、酸素含有雰囲気下、550℃以上1200℃未満の温度で1次混合物を熱処理することにより、仮焼粉末としてZnとWとを含む複酸化物の粉末を形成することを含む。
酸化物焼結体の原料粉末として、インジウム酸化物粉末(たとえばIn2O3粉末)、タングステン酸化物粉末(たとえばWO3粉末、WO2.72粉末、WO2粉末)、亜鉛酸化物粉末(たとえばZnO粉末)等、酸化物焼結体を構成する金属元素の酸化物粉末を準備する。タングステン酸化物粉末としてはWO3粉末だけでなく、WO2.72粉末、WO2粉末のようなWO3粉末に比べて酸素が欠損した化学組成を有する粉末を原料として用いることが、半導体デバイスの電界効果移動度および光照射下での信頼性を高める観点から好ましい。かかる観点から、WO2.72粉末およびWO2粉末の少なくとも1つをタングステン酸化物粉末の少なくとも一部として用いることがより好ましい。原料粉末の純度は、酸化物焼結体への意図しない金属元素およびSiの混入を防止し、安定した物性を得る観点から、99.9質量%以上の高純度であることが好ましい。
(2-1)亜鉛酸化物粉末とタングステン酸化物粉末との1次混合物を調製する工程
上記原料粉末の内、亜鉛酸化物粉末とタングステン酸化物粉末とを混合(または粉砕混合)する。このとき、酸化物焼結体の結晶相としてZnWO4型結晶相を得たい場合は、タングステン酸化物粉末と亜鉛酸化物粉末とをモル比で1:1の割合で、Zn2W3O8型結晶相を得たい場合は、タングステン酸化物粉末と亜鉛酸化物粉末とをモル比で3:2の割合で混合する。上述のように、酸化物焼結体の見かけ密度をより効果的に高めるとともに、スパッタ中のスパッタターゲットの表面粗さを小さくする観点、ならびに半導体デバイスの電界効果移動度および光照射下での信頼性を高める観点からは、酸化物焼結体は、ZnWO4型相を含むことが好ましい。タングステン酸化物粉末と亜鉛酸化物粉末とを混合する方法に特に制限はなく、乾式および湿式のいずれの方式であってもよく、具体的には、ボールミル、遊星ボールミル、ビーズミル等を用いて粉砕混合される。このようにして、原料粉末の1次混合物が得られる。湿式の粉砕混合方式を用いて得られた混合物の乾燥には、自然乾燥やスプレードライヤのような乾燥方法を用いることができる。
上記原料粉末の内、インジウム酸化物粉末とタングステン酸化物粉末とを混合(または粉砕混合)する。このとき、酸化物焼結体の結晶相としてIn6WO12型結晶相を得たい場合は、タングステン酸化物粉末とインジウム酸化物粉末とをモル比で1:3の割合で混合する。タングステン酸化物粉末とインジウム酸化物粉末とを混合する方法に特に制限はなく、乾式および湿式のいずれの方式であってもよく、具体的には、ボールミル、遊星ボールミル、ビーズミル等を用いて粉砕混合される。このようにして、原料粉末の1次混合物が得られる。湿式の粉砕混合方式を用いて得られた混合物の乾燥には、自然乾燥やスプレードライヤのような乾燥方法を用いることができる。
(3-1)タングステン酸亜鉛酸化物の仮焼粉末を形成する工程
得られた1次混合物を熱処理(仮焼)して、仮焼粉末(ZnとWとを含む複酸化物粉末)を形成する。1次混合物の仮焼温度は、仮焼物の粒径が大きくなりすぎて酸化物焼結体の見かけ密度が低下したり、スパッタ中のスパッタターゲットの表面粗さが大きくなったりすることがないように1200℃未満であることが好ましく、仮焼生成物としてZnとWとを含む複酸化物粉末を得るために、また、ZnWO4型結晶相を得るためには550℃以上であることが好ましい。より好ましくは550℃以上1000℃未満であり、さらに好ましくは550℃以上900℃以下である。仮焼温度は結晶相が形成される温度である限り、仮焼粉の粒径をなるべく小さくできる点から低い方が好ましい。このようにして、ZnWO4型結晶相を含む仮焼粉末が得ることができる。仮焼雰囲気は、酸素を含む雰囲気であればよいが、大気圧もしくは大気よりも圧力の高い空気雰囲気、または大気圧もしくは大気よりも圧力の高い酸素を25体積%以上含む酸素-窒素混合雰囲気が好ましい。生産性が高いことから、大気圧またはその近傍下での空気雰囲気がより好ましい。
得られた1次混合物を熱処理(仮焼)して、仮焼粉末(InとWとを含む複酸化物粉末)を形成する。1次混合物の仮焼温度は、仮焼物の粒径が大きくなりすぎて酸化物焼結体の見かけ密度が低下したり、スパッタ中のスパッタターゲットの表面粗さが大きくなったりすることがないように1400℃未満であることが好ましく、仮焼生成物としてInとWとを含む複酸化物粉末を得るために、また、In6WO12型結晶相を得るためには700℃以上であることが好ましい。より好ましくは800℃以上1300℃未満である。仮焼温度は結晶相が形成される温度である限り、仮焼粉の粒径をなるべく小さくできる点から低い方が好ましい。このようにして、In6WO12型結晶相を含む仮焼粉末が得ることができる。仮焼雰囲気は、酸素を含む雰囲気であればよいが、大気圧もしくは大気よりも圧力の高い空気雰囲気、または大気圧もしくは大気よりも圧力の高い酸素を25体積%以上含む酸素-窒素混合雰囲気が好ましい。生産性が高いことから、大気圧またはその近傍下での空気雰囲気がより好ましい。
次に、得られた仮焼粉末と、上記原料粉末の内の残りの粉末〔インジウム酸化物粉末(たとえばIn2O3粉末)または亜鉛酸化物粉末(例えばZnO粉末)〕とを、1次混合物の調製と同様にして、混合(または粉砕混合)する。このようにして、原料粉末の2次混合物が得られる。タングステン酸化物は、上記仮焼工程により複酸化物として存在していることが好ましい。
次に、得られた2次混合物を成形する。2次混合物を成形する方法に特に制限はないが、酸化物焼結体の見かけ密度を高くする点から、一軸プレス法、CIP(冷間静水圧処理)法、キャスティング法等が好ましい。
次に、得られた成形体を焼結して、酸化物焼結体を形成する。この際、生産性の面からホットプレス焼結法は用いないことが好ましい。成形体の焼結温度に特に制限はないが、見かけ密度が6.4g/cm3より大きく、スパッタ中のスパッタターゲットの表面粗さが小さい酸化物焼結体を得るために、900℃以上で、1200℃より低いことが好ましい。焼結雰囲気にも特に制限はないが、酸化物焼結体の構成結晶の粒径が大きくなることを防いでスパッタ中のスパッタターゲットの表面粗さが小さい酸化物焼結体を得る観点から、大気圧またはその近傍下での空気雰囲気が好ましい。
本実施形態に係るスパッタターゲットは、実施形態1の酸化物焼結体を含む。したがって、本実施形態に係るスパッタターゲットは、電界効果移動度が高く、光照射下での信頼性も高い半導体デバイスの酸化物半導体膜をスパッタ法で形成するために好適に用いることができる。
図1Aおよび図1Bを参照して、本実施形態に係る半導体デバイス10は、実施形態1の酸化物焼結体を用いて形成されるか、または実施形態3のスパッタターゲット用いてスパッタ法により形成した酸化物半導体膜14を含む。かかる酸化物半導体膜14を含むため、本実施形態に係る半導体デバイスは、電界効果移動度が高く、光照射下での信頼性も高いという特性を有することができる。
測定方法:In-plane法(スリットコリメーション法)、
X線発生部:対陰極Cu、出力50kV 300mA、
検出部:シンチレーションカウンタ、
入射部:スリットコリメーション、
ソーラースリット:入射側 縦発散角0.48°
受光側 縦発散角0.41°、
スリット:入射側 S1=1mm*10mm
受光側 S2=0.2mm*10mm、
走査条件:走査軸 2θχ/φ、
走査モード:ステップ測定、走査範囲 10~80°、ステップ幅0.1°、
ステップ時間 8sec.。
測定方法:極微電子線回折法、
加速電圧:200kV、
ビーム径:測定対象である酸化物半導体膜の膜厚と同じか、または同等。
図4Aを参照して、基板11上にゲート電極12を形成する。基板11は、特に制限されないが、透明性、価格安定性、および表面平滑性を高くする観点から、石英ガラス基板、無アルカリガラス基板、アルカリガラス基板等であることが好ましい。ゲート電極12は、特に制限されないが、耐酸化性が高くかつ電気抵抗が低い点から、Mo電極、Ti電極、W電極、Al電極、Cu電極等であることが好ましい。ゲート電極12の形成方法は、特に制限されないが、基板11の主面上に大面積で均一に形成できる点から、真空蒸着法、スパッタ法等であることが好ましい。図4Aに示されるように、基板11の表面上に部分的にゲート電極12を形成する場合には、フォトレジストを使ったエッチング法を用いることができる。
図4Bを参照して、ゲート電極12および基板11上に絶縁層としてゲート絶縁膜13を形成する。ゲート絶縁膜13の形成方法は、特に制限はないが、大面積で均一に形成できる点および絶縁性を確保する点から、プラズマCVD(化学気相堆積)法等であることが好ましい。
図4Cを参照して、ゲート絶縁膜13上にチャネル層として酸化物半導体膜14を形成する。上述のように、酸化物半導体膜14は、スパッタ法により成膜する工程を含んで形成されることが好ましく、たとえばスパッタ法による成膜後に加熱処理するか、またはスパッタ法により成膜を行いながら加熱処理することによって形成されることが好ましい。スパッタ法の原料ターゲット(スパッタターゲット)としては、上記実施形態1の酸化物焼結体を用いる。
図4Dを参照して、酸化物半導体膜14上にソース電極15およびドレイン電極16を互いに接触しないように形成する。ソース電極15およびドレイン電極16は、特に制限はないが、耐酸化性が高く、電気抵抗が低く、かつ酸化物半導体膜14との接触電気抵抗が低いことから、Mo電極、Ti電極、W電極、Al電極、Cu電極等であることが好ましい。ソース電極15およびドレイン電極16を形成する方法は、特に制限はないが、酸化物半導体膜14が形成された基板11の主面上に大面積で均一に形成できる点から、真空蒸着法、スパッタリング法等であることが好ましい。ソース電極15およびドレイン電極16を互いに接触しないように形成する方法は、特に制限はないが、大面積で均一なソース電極15とドレイン電極16のパターンを形成できる点から、フォトレジストを使ったエッチング法による形成であることが好ましい。
最後に、通常は、加熱処理を施す。加熱処理は基板を加熱することによって実施できる。基板温度は、好ましくは100℃以上250℃以下である。加熱処理の雰囲気は、大気中、窒素ガス中、窒素ガス-酸素ガス中、Arガス中、Ar-酸素ガス中、水蒸気含有大気中、水蒸気含有窒素中など、各種雰囲気であってよい。好ましくは、窒素、Arガス中などの不活性雰囲気である。雰囲気圧力は、大気圧のほか、減圧条件下(たとえば0.1Pa未満)、加圧条件下(たとえば0.1Pa~9MPa)であることができるが、好ましくは大気圧である。加熱処理の時間は、たとえば3分~2時間程度であることができ、好ましくは10分~90分程度である。
(1)酸化物焼結体の作製
(1-1)粉末原料の準備
表1に示す組成とメジアン粒径d50(表1において「W粒径」と表記した。)を有し、純度が99.99質量%のタングステン酸化物粉末(表1において「W」と表記した。)と、メジアン粒径d50が1.0μmで純度が99.99質量%のZnO粉末(表1において「Z」と表記した。)と、メジアン粒径d50が1.0μmで純度が99.99質量%のIn2O3粉末(表1において「I」と表記した。)と、を準備した。
まず、ボールミルに、準備した原料粉末の内、タングステン酸化物粉末とZnO粉末、またはタングステン酸化物粉末とインジウム酸化物粉末とを入れて、18時間粉砕混合することにより原料粉末の1次混合物を調製した。タングステン酸化物粉末とZnO粉末とのモル混合比率は、およそタングステン酸化物粉末:ZnO粉末=1:1とした。タングステン酸化物粉末とインジウム酸化物粉末とのモル混合比率は、およそタングステン酸化物粉末:In2O3粉末=1:3とした。粉砕混合の際、分散媒としてエタノールを用いた。得られた原料粉末の1次混合物は大気中で乾燥させた。
次に、得られた原料粉末の1次混合物をアルミナ製坩堝に入れて、空気雰囲気中、表1に示す仮焼温度で8時間仮焼し、ZnWO4型結晶相で構成された仮焼粉末またはIn6WO12型結晶相で構成された仮焼粉末を得た。表1に、得られた仮焼粉末を構成する結晶相の組成(種類)を示す。実施例7~14では、ZnWO4型結晶相で構成された仮焼粉末およびIn6WO12型結晶相で構成された仮焼粉末の2種類の仮焼粉末を作製し、使用した。
次に、得られた仮焼粉末を、準備した残りの原料粉末であるIn2O3粉末またはZnO粉末とともにポットへ投入し、さらに粉砕混合ボールミルに入れて12時間粉砕混合することにより原料粉末の2次混合物を調製した。これらの粉末の混合比は、混合物中のW、ZnおよびInのモル比が表1に示されるとおりとなるようにした。粉砕混合の際、分散媒としてエタノールを用いた。得られた混合粉末はスプレードライで乾燥させた。
次に、得られた2次混合物をプレスにより成形し、さらにCIPにより室温(5℃~30℃)の静水中、190MPaの圧力で加圧成形して、直径100mmで厚み約9mmの円板状の成形体を得た。
次に、得られた成形体を大気圧下、空気雰囲気中にて表1に示す焼結温度で8時間焼結して、タングステンおよび亜鉛が固溶したビックスバイト型結晶相(In2O3型相)を含む第1結晶相を含む酸化物焼結体を得た。タングステンおよび亜鉛が固溶しているとの判断は、X線回折の測定において、ピーク位置が、JCPDSカードの6-0416に規定されるピーク位置からずれていることの確認に基づいている。
〔A〕第1結晶相、第2結晶相および第4結晶相の同定
酸化物焼結体の一部からサンプルを採取して、粉末X線回折法による結晶解析を行い、ビックスバイト型結晶相、2θの34.74degより大きく34.97degより小さいより小さい位置に第1回折ピークを有する第2結晶相、および2θの31.77degより大きく32.00degより小さい位置に第2回折ピークを有する第4結晶相の存在の有無を確認した。X線回折の測定条件は以下のとおりとした。
θ-2θ法、
X線源:Cu Kα線、
X線管球電圧:45kV、
X線管球電流:40mA、
ステップ幅:0.03deg、
ステップ時間:1秒/ステップ、
測定範囲2θ:10deg~90deg。
酸化物焼結体の一部からサンプルを採取し、該サンプルの表面を研磨して平滑にした。次いで、SEM-EDX(エネルギー分散型ケイ光X線分析計を付帯する走査型二次電子顕微鏡)を用いて、サンプルの当該表面をSEM(走査型二次電子顕微鏡)で観察し、各結晶粒子の金属元素の組成比をEDX(エネルギー分散型ケイ光X線分析計)で分析した。そして、それらの結晶粒子の金属元素の組成比の傾向に基づいて、結晶粒子のグループ分けを行った。具体的には、Znを含有し、より典型的にはZn含有率〔In、WおよびZnの合計に対するZnの含有率(原子%)〕が後述するグループBよりも高い結晶粒子のグループAと、Zn含有率が非常に低いかまたはZnを含有せず、かつ、グループAに比べてIn含有率(In、WおよびZnの合計に対するInの含有率(原子%))が高い結晶粒子のグループB(インジウム高含有型結晶相)とに分けた。グループBの結晶粒が第1結晶相であると判断した。
上述の〔A〕第1結晶相、第2結晶相および第4結晶相の同定のためのX線回折の測定結果に基づき、上述の式に従ってIaおよびIbを測定し、Ia/Ibを算出した。結果を表2に示す。
上述の〔B〕第1結晶相が主成分であることの確認およびインジウム高含有型結晶相占有率の測定において、グループAに分けられた結晶相を第3結晶相と判断した。またこの表面分析でのSEM観察において500倍の反射電子像を測定し、第1結晶相に分類されるグループBに比して濃いグレーに観察される第3結晶相を構成する結晶粒子について、上述の方法にしたがって平均長軸径および平均アスペクト比を測定した。結果を表2に示す。
上述の〔A〕X線回折の測定において、併せて、第5結晶相、タングステン酸インジウム化合物結晶相、六方晶ウルツ型結晶相およびIn2O3(ZnO)5の存在の有無を確認した。いずれの実施例・比較例においても、タングステン酸インジウム化合物結晶相および六方晶ウルツ型結晶相の存在は認められなかった。
ZW:タングステン酸亜鉛化合物結晶相(第3結晶相および第5結晶相)、
IZ:In2O3(ZnO)5(第3結晶相)。
得られた酸化物焼結体中のIn、ZnおよびWの含有量は、ICP質量分析法により測定した。これらの含有量に基づいて、酸化物焼結体のW含有率(原子%)、Zn含有率(原子%)、およびZn/W比(原子数比)をそれぞれ求めた。結果を表2に示す。
得られた酸化物焼結体の見かけ密度はアルキメデス法により求めた。
原料粉末であるタングステン酸化物粉末、ZnO粉末およびIn2O3粉末の混合比が表1に示されるとおりとなるようにしたこと、ならびに、仮焼粉末を形成することなく、これらの原料粉末を一度に混合し表1に示される温度で焼結したこと以外は実施例と同じ方法で酸化物焼結体を作製し、物性評価を行った。比較例3の酸化物焼結体については、第3結晶相がインジウム高含有型結晶相に分散しておらず、お互いに接触した形であり、第3結晶相の粒子形状を特定することができなかったため、平均長軸径および平均アスペクト比を測定することはできなかった。いずれの比較例においても、見かけ密度を高めるためには焼結温度は、実施例に比較して高くする必要があった。焼結温度を1170℃としたこと以外は比較例1から比較例4と同様にして酸化物焼結体を作製したところ、これらの酸化物焼結体の見かけ密度はいずれも6.3g/cm3であった。
(2-1)スパッタターゲットの作製
得られた酸化物焼結体を、直径3インチ(76.2mm)×厚さ6mmに加工した後、銅のバッキングプレートにインジウム金属を用いて貼り付けた。
作製したスパッタターゲットをスパッタリング装置(図示せず)の成膜室内に設置した。スパッタターゲットは、銅のバッキングプレートを介して水冷されている。基板として、2インチサイズの鏡面Siウエハをスパッタターゲットに対向する形でセットした。成膜室内を6×10-5Pa程度の真空度として、ターゲットを次のようにしてスパッタリングした。
(3-1)酸化物半導体膜を備える半導体デバイス(TFT)の作製
次の手順で図3に示される半導体デバイス30と類似の構成を有するTFTを作製した。図4Aを参照して、まず、基板11として50mm×50mm×厚み0.6mmの合成石英ガラス基板を準備し、その基板11上にスパッタリング法によりゲート電極12として厚み100nmのMo電極を形成した。次いで、図4Aに示されるように、フォトレジストを使ったエッチングによりゲート電極12を所定の形状とした。
作製したTFTが備える酸化物半導体膜14の結晶性を上述の測定方法および定義に従って評価した。表3における「結晶性」の欄には、ナノ結晶である場合には「ナノ結晶」と、アモルファスである場合には「アモルファス」と記載している。また、酸化物半導体膜14中のIn、WおよびZnの含有量を、RBS(ラザフォード後方散乱分析)により測定した。これらの含有量に基づいて酸化物半導体膜14のW含有率(原子%)、Zn含有率(原子%)、およびZn/W比(原子数比)をそれぞれ求めた。結果を表3に示す。
上記(2-1)に従ってスパッタターゲットを作製した。次いで、上記(2-2)と同様にして、20時間のスパッタリングを行った。次に、2インチサイズの鏡面Siウエハをスパッタターゲットに対向する形でセットした。成膜室内を6×10-5Pa程度の真空度として、ターゲットを次のようにしてスパッタリングした。ターゲットと基板の間にシャッターを入れた状態で、成膜室内へAr(アルゴン)ガスとO2(酸素)ガスとの混合ガスを0.5Paの圧力まで導入した。混合ガス中のO2ガス含有率は25体積%であった。ターゲットに250WのDC電力を印加してスパッタリング放電を起こした。10分間保持した後、基板とターゲットの間からシャッターをはずし、基板へ酸化物半導体膜を形成した。酸化物半導体膜の膜厚が2μmになるように成膜時間を調整した。
半導体デバイス10であるTFTの特性を次のようにして評価した。まず、ゲート電極12、ソース電極15およびドレイン電極16に測定針を接触させた。ソース電極15とドレイン電極16との間に0.2Vのソース-ドレイン間電圧Vdsを印加し、ソース電極15とゲート電極12との間に印加するソース-ゲート間電圧Vgsを-10Vから15Vに変化させて、そのときのソース-ドレイン間電流Idsを測定した。そして、ソース-ゲート間電圧Vgsとソース-ドレイン間電流Idsの平方根〔(Ids)1/2〕との関係をグラフ化した(以下、このグラフを「Vgs-(Ids)1/2曲線」ともいう。)。Vgs-(Ids)1/2曲線に接線を引き、その接線の傾きが最大となる点を接点とする接線がx軸(Vgs)と交わる点(x切片)を閾値電圧Vthとした。閾値電圧Vthは、大気圧窒素雰囲気中250℃10分間の加熱処理を実施した後(Vth(250℃))と、大気圧窒素雰囲気中350℃10分間の加熱処理を実施した後(Vth(350℃))のTFTについて測定した。Vthは、0V以上であることが望ましいとされており、さらにはTFTを表示装置に用いる場合、a-Siとの駆動電圧の同一性から1.0Vにより近い方が望ましいとされている。
gm=dIds/dVgs 〔a〕
に従って、ソース-ドレイン間電流Idsをソース-ゲート間電圧Vgsについて微分することによりgmを導出した。そしてVgs=10.0Vにおけるgmの値を用いて、下記式〔b〕:
μfe=gm・CL/(CW・Ci・Vds) 〔b〕
に基づいて、電界効果移動度μfeを算出した。上記式〔b〕におけるチャネル長さCLは30μmであり、チャネル幅CWは40μmである。また、ゲート絶縁膜13のキャパシタンスCiは3.4×10-8F/cm2とし、ソース-ドレイン間電圧Vdsは0.5Vとした。
Claims (17)
- インジウム、タングステンおよび亜鉛を含有する酸化物焼結体であって、
前記酸化物焼結体の主成分であり、ビックスバイト型結晶相を含む第1結晶相と、
X線回折における2θの34.74degより大きく34.97degより小さい位置に第1回折ピークを有する第2結晶相と、
を含み、
前記酸化物焼結体の見かけ密度が6.4g/cm3より大きく7.5g/cm3以下であり、
前記酸化物焼結体中のインジウム、タングステンおよび亜鉛の合計に対するタングステンの含有率が0.01原子%より大きく5.0原子%以下であり、
前記酸化物焼結体中のインジウム、タングステンおよび亜鉛の合計に対する亜鉛の含有率が1.2原子%以上50原子%未満であり、
前記酸化物焼結体中のタングステンに対する亜鉛の原子比が1.0より大きく20000より小さい、酸化物焼結体。 - 前記第1結晶相とは異なる結晶相であって、亜鉛を含有する第3結晶相を含み、
前記第3結晶相を構成する粒子は、平均長軸径が3μm以上50μm以下であり、平均アスペクト比が1.5以上50以下である、請求項1に記載の酸化物焼結体。 - 前記第3結晶相は、前記第1結晶相に分散している、請求項2に記載の酸化物焼結体。
- 前記第3結晶相は、X線回折における2θの31.77degより大きく32.00degより小さい位置に第2回折ピークを有する第4結晶相を含む、請求項2または請求項3に記載の酸化物焼結体。
- 前記第1回折ピークのピーク強度Iaと前記第2回折ピークのピーク強度Ibとの比Ia/Ibが0.05以上3以下である、請求項4に記載の酸化物焼結体。
- 前記第3結晶相は、タングステン酸亜鉛化合物結晶相である第5結晶相を含む、請求項2から請求項5のいずれか1項に記載の酸化物焼結体。
- 前記第1結晶相は、タングステン酸インジウム化合物結晶相をさらに含む、請求項1から請求項6のいずれか1項に記載の酸化物焼結体。
- 請求項1から請求項7のいずれか1項に記載の酸化物焼結体を含む、スパッタターゲット。
- 酸化物半導体膜を含む半導体デバイスの製造方法であって、
請求項8に記載のスパッタターゲットを用意する工程と、
前記スパッタターゲットを用いてスパッタ法により前記酸化物半導体膜を形成する工程と、
を含む、半導体デバイスの製造方法。 - 前記酸化物半導体膜中のインジウム、タングステンおよび亜鉛の合計に対するタングステンの含有率が0.01原子%より大きく5.0原子%以下であり、
前記酸化物半導体膜中のインジウム、タングステンおよび亜鉛の合計に対する亜鉛の含有率が1.2原子%以上50原子%未満であり、
前記酸化物半導体膜中のタングステンに対する亜鉛の原子比が1.0より大きく20000より小さい、請求項9に記載の半導体デバイスの製造方法。 - 前記酸化物半導体膜は、ナノ結晶酸化物およびアモルファス酸化物の少なくともいずれか1つで構成される、請求項9または請求項10に記載の半導体デバイスの製造方法。
- 請求項1から請求項7のいずれか1項に記載の酸化物焼結体の製造方法であって、
インジウム酸化物粉末とタングステン酸化物粉末との1次混合物を調製する工程と、
前記1次混合物を熱処理することにより仮焼粉末を形成する工程と、
前記仮焼粉末を含む原料粉末の2次混合物を調製する工程と、
前記2次混合物を成形することにより成形体を形成する工程と、
前記成形体を焼結することにより酸化物焼結体を形成する工程と、
を含み、
前記仮焼粉末を形成する工程は、酸素含有雰囲気下、700℃以上1400℃未満の温度で前記1次混合物を熱処理することにより、前記仮焼粉末としてインジウムとタングステンとを含む複酸化物の粉末を形成することを含む、酸化物焼結体の製造方法。 - 前記複酸化物がIn6WO12型結晶相を含む、請求項12に記載の酸化物焼結体の製造方法。
- 請求項1から請求項7のいずれか1項に記載の酸化物焼結体の製造方法であって、
亜鉛酸化物粉末とタングステン酸化物粉末との1次混合物を調製する工程と、
前記1次混合物を熱処理することにより仮焼粉末を形成する工程と、
前記仮焼粉末を含む原料粉末の2次混合物を調製する工程と、
前記2次混合物を成形することにより成形体を形成する工程と、
前記成形体を焼結することにより酸化物焼結体を形成する工程と、
を含み、
前記仮焼粉末を形成する工程は、酸素含有雰囲気下、550℃以上1200℃未満の温度で前記1次混合物を熱処理することにより、前記仮焼粉末として亜鉛とタングステンとを含む複酸化物の粉末を形成することを含む、酸化物焼結体の製造方法。 - 前記複酸化物がZnWO4型結晶相を含む、請求項14に記載の酸化物焼結体の製造方法。
- 前記タングステン酸化物粉末は、WO3結晶相、WO2結晶相、およびWO2.72結晶相からなる群より選ばれる少なくとも1種の結晶相を含む、請求項12から請求項15のいずれか1項に記載の酸化物焼結体の製造方法。
- 前記タングステン酸化物粉末は、メジアン粒径d50が0.1μm以上4μm以下である、請求項12から請求項16のいずれか1項に記載の酸化物焼結体の製造方法。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US16/486,906 US11492694B2 (en) | 2017-02-20 | 2017-09-28 | Oxide sintered material, method of producing oxide sintered material, sputtering target, and method of producing semiconductor device |
JP2019500184A JP7024773B2 (ja) | 2017-02-20 | 2017-09-28 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 |
CN201780086594.4A CN110312691B (zh) | 2017-02-20 | 2017-09-28 | 氧化物烧结材料、制造氧化物烧结材料的方法、溅射靶和制造半导体器件的方法 |
KR1020197023376A KR102401708B1 (ko) | 2017-02-20 | 2017-09-28 | 산화물 소결체 및 그의 제조 방법, 스퍼터 타겟, 그리고 반도체 디바이스의 제조 방법 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2017-028972 | 2017-02-20 | ||
JP2017028972 | 2017-02-20 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2018150621A1 true WO2018150621A1 (ja) | 2018-08-23 |
Family
ID=63170269
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2017/035301 WO2018150621A1 (ja) | 2017-02-20 | 2017-09-28 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 |
Country Status (6)
Country | Link |
---|---|
US (1) | US11492694B2 (ja) |
JP (1) | JP7024773B2 (ja) |
KR (1) | KR102401708B1 (ja) |
CN (1) | CN110312691B (ja) |
TW (1) | TWI772334B (ja) |
WO (1) | WO2018150621A1 (ja) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2018150622A1 (ja) * | 2017-02-20 | 2018-08-23 | 住友電気工業株式会社 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 |
CN112390622A (zh) * | 2020-11-23 | 2021-02-23 | 先导薄膜材料(广东)有限公司 | 一种eigzo靶材的制备方法 |
CN114702304B (zh) * | 2022-05-11 | 2023-03-17 | 郑州大学 | 一种铟钨氧化物靶材及其制备方法 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015107907A (ja) * | 2013-10-23 | 2015-06-11 | 住友電気工業株式会社 | 酸化物焼結体および半導体デバイス |
JP2015193525A (ja) * | 2014-03-25 | 2015-11-05 | 住友電気工業株式会社 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイス |
WO2016129146A1 (ja) * | 2015-02-13 | 2016-08-18 | 住友電気工業株式会社 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイス |
JP2017057108A (ja) * | 2015-09-16 | 2017-03-23 | 住友電気工業株式会社 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 |
JP2017057109A (ja) * | 2015-09-16 | 2017-03-23 | 住友電気工業株式会社 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3746094B2 (ja) | 1995-06-28 | 2006-02-15 | 出光興産株式会社 | ターゲットおよびその製造方法 |
JP4826066B2 (ja) * | 2004-04-27 | 2011-11-30 | 住友金属鉱山株式会社 | 非晶質の透明導電性薄膜およびその製造方法、並びに、該非晶質の透明導電性薄膜を得るためのスパッタリングターゲットおよびその製造方法 |
JP5237557B2 (ja) | 2007-01-05 | 2013-07-17 | 出光興産株式会社 | スパッタリングターゲット及びその製造方法 |
JP4662075B2 (ja) | 2007-02-02 | 2011-03-30 | 株式会社ブリヂストン | 薄膜トランジスタ及びその製造方法 |
KR101312259B1 (ko) | 2007-02-09 | 2013-09-25 | 삼성전자주식회사 | 박막 트랜지스터 및 그 제조방법 |
EP2421048A4 (en) * | 2009-04-17 | 2012-08-29 | Bridgestone Corp | THIN FILM TRANSISTOR AND METHOD FOR MANUFACTURING THE SAME |
JP6428780B2 (ja) * | 2014-08-12 | 2018-11-28 | 住友電気工業株式会社 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイス |
KR101816468B1 (ko) * | 2014-10-22 | 2018-01-08 | 스미토모덴키고교가부시키가이샤 | 산화물 소결체 및 반도체 디바이스 |
CN106104811A (zh) * | 2015-01-26 | 2016-11-09 | 住友电气工业株式会社 | 氧化物半导体膜和半导体器件 |
-
2017
- 2017-09-28 US US16/486,906 patent/US11492694B2/en active Active
- 2017-09-28 CN CN201780086594.4A patent/CN110312691B/zh active Active
- 2017-09-28 WO PCT/JP2017/035301 patent/WO2018150621A1/ja active Application Filing
- 2017-09-28 JP JP2019500184A patent/JP7024773B2/ja active Active
- 2017-09-28 KR KR1020197023376A patent/KR102401708B1/ko active IP Right Grant
- 2017-10-31 TW TW106137555A patent/TWI772334B/zh active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015107907A (ja) * | 2013-10-23 | 2015-06-11 | 住友電気工業株式会社 | 酸化物焼結体および半導体デバイス |
JP2015193525A (ja) * | 2014-03-25 | 2015-11-05 | 住友電気工業株式会社 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイス |
WO2016129146A1 (ja) * | 2015-02-13 | 2016-08-18 | 住友電気工業株式会社 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイス |
JP2017057108A (ja) * | 2015-09-16 | 2017-03-23 | 住友電気工業株式会社 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 |
JP2017057109A (ja) * | 2015-09-16 | 2017-03-23 | 住友電気工業株式会社 | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 |
Also Published As
Publication number | Publication date |
---|---|
US11492694B2 (en) | 2022-11-08 |
KR102401708B1 (ko) | 2022-05-26 |
TWI772334B (zh) | 2022-08-01 |
JPWO2018150621A1 (ja) | 2019-12-12 |
KR20190120752A (ko) | 2019-10-24 |
CN110312691B (zh) | 2022-04-01 |
US20200232085A1 (en) | 2020-07-23 |
JP7024773B2 (ja) | 2022-02-24 |
CN110312691A (zh) | 2019-10-08 |
TW201831426A (zh) | 2018-09-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP6493502B2 (ja) | 酸化物焼結体の製造方法 | |
JP6308191B2 (ja) | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 | |
WO2018150621A1 (ja) | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 | |
JP6593268B2 (ja) | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 | |
WO2018211977A1 (ja) | 酸化物焼結体およびその製造方法、スパッタターゲット、酸化物半導体膜、ならびに半導体デバイスの製造方法 | |
JP6350466B2 (ja) | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 | |
WO2018150622A1 (ja) | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 | |
JP6493601B2 (ja) | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 | |
JP6458883B2 (ja) | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 | |
WO2018083837A1 (ja) | 酸化物焼結体およびその製造方法、スパッタターゲット、ならびに半導体デバイスの製造方法 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 17896544 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 2019500184 Country of ref document: JP Kind code of ref document: A |
|
ENP | Entry into the national phase |
Ref document number: 20197023376 Country of ref document: KR Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 17896544 Country of ref document: EP Kind code of ref document: A1 |