JP2020198380A - Glass composition, manufacturing method for glass composition, conductive paste, and solar cell - Google Patents
Glass composition, manufacturing method for glass composition, conductive paste, and solar cell Download PDFInfo
- Publication number
- JP2020198380A JP2020198380A JP2019104493A JP2019104493A JP2020198380A JP 2020198380 A JP2020198380 A JP 2020198380A JP 2019104493 A JP2019104493 A JP 2019104493A JP 2019104493 A JP2019104493 A JP 2019104493A JP 2020198380 A JP2020198380 A JP 2020198380A
- Authority
- JP
- Japan
- Prior art keywords
- glass composition
- less
- glass
- electrode
- present
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000011521 glass Substances 0.000 title claims abstract description 317
- 239000000203 mixture Substances 0.000 title claims abstract description 275
- 238000004519 manufacturing process Methods 0.000 title claims description 36
- 239000000758 substrate Substances 0.000 claims abstract description 114
- 239000000843 powder Substances 0.000 claims abstract description 84
- 229910052751 metal Inorganic materials 0.000 claims abstract description 38
- 239000002184 metal Substances 0.000 claims abstract description 38
- 238000002156 mixing Methods 0.000 claims abstract description 26
- 229910015902 Bi 2 O 3 Inorganic materials 0.000 claims description 22
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 22
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 18
- 229910052710 silicon Inorganic materials 0.000 claims description 18
- 239000010703 silicon Substances 0.000 claims description 18
- 229910052782 aluminium Inorganic materials 0.000 claims description 9
- 229910052709 silver Inorganic materials 0.000 claims description 9
- 229910052802 copper Inorganic materials 0.000 claims description 8
- 229910052697 platinum Inorganic materials 0.000 claims description 8
- 229910052737 gold Inorganic materials 0.000 claims description 7
- 229910052763 palladium Inorganic materials 0.000 claims description 7
- 239000004065 semiconductor Substances 0.000 abstract description 77
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract description 7
- 239000000377 silicon dioxide Substances 0.000 abstract description 3
- 235000012239 silicon dioxide Nutrition 0.000 abstract description 3
- WMWLMWRWZQELOS-UHFFFAOYSA-N bismuth(iii) oxide Chemical compound O=[Bi]O[Bi]=O WMWLMWRWZQELOS-UHFFFAOYSA-N 0.000 abstract 2
- 229910052681 coesite Inorganic materials 0.000 abstract 1
- 229910052906 cristobalite Inorganic materials 0.000 abstract 1
- 230000000593 degrading effect Effects 0.000 abstract 1
- 229910052682 stishovite Inorganic materials 0.000 abstract 1
- 229910052905 tridymite Inorganic materials 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 58
- 238000000034 method Methods 0.000 description 25
- 230000000694 effects Effects 0.000 description 18
- 238000010304 firing Methods 0.000 description 11
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 11
- 229910052581 Si3N4 Inorganic materials 0.000 description 10
- 230000000052 comparative effect Effects 0.000 description 10
- 230000035515 penetration Effects 0.000 description 10
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 10
- 230000015572 biosynthetic process Effects 0.000 description 9
- 238000006243 chemical reaction Methods 0.000 description 9
- 238000002425 crystallisation Methods 0.000 description 9
- 230000008025 crystallization Effects 0.000 description 9
- 230000009477 glass transition Effects 0.000 description 9
- 239000011347 resin Substances 0.000 description 9
- 229920005989 resin Polymers 0.000 description 9
- 239000010949 copper Substances 0.000 description 8
- 238000011156 evaluation Methods 0.000 description 8
- 239000002245 particle Substances 0.000 description 8
- 238000010298 pulverizing process Methods 0.000 description 8
- 230000002542 deteriorative effect Effects 0.000 description 7
- 230000006872 improvement Effects 0.000 description 7
- 229910052809 inorganic oxide Inorganic materials 0.000 description 7
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Substances [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 7
- 230000009257 reactivity Effects 0.000 description 7
- 239000011230 binding agent Substances 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 230000000149 penetrating effect Effects 0.000 description 6
- 239000002994 raw material Substances 0.000 description 6
- 239000002904 solvent Substances 0.000 description 6
- 239000010931 gold Substances 0.000 description 5
- 239000012535 impurity Substances 0.000 description 5
- 239000011810 insulating material Substances 0.000 description 5
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 5
- 238000002360 preparation method Methods 0.000 description 5
- 239000010944 silver (metal) Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 4
- 239000000654 additive Substances 0.000 description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 4
- 239000001913 cellulose Substances 0.000 description 4
- 229920002678 cellulose Polymers 0.000 description 4
- 238000000576 coating method Methods 0.000 description 4
- 238000004455 differential thermal analysis Methods 0.000 description 4
- 238000002844 melting Methods 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- OAYXUHPQHDHDDZ-UHFFFAOYSA-N 2-(2-butoxyethoxy)ethanol Chemical compound CCCCOCCOCCO OAYXUHPQHDHDDZ-UHFFFAOYSA-N 0.000 description 3
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 description 3
- 229910021364 Al-Si alloy Inorganic materials 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 3
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 3
- 229910010413 TiO 2 Inorganic materials 0.000 description 3
- 239000011362 coarse particle Substances 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 3
- 238000002161 passivation Methods 0.000 description 3
- -1 2 O 3 Substances 0.000 description 2
- FPZWZCWUIYYYBU-UHFFFAOYSA-N 2-(2-ethoxyethoxy)ethyl acetate Chemical compound CCOCCOCCOC(C)=O FPZWZCWUIYYYBU-UHFFFAOYSA-N 0.000 description 2
- 239000004925 Acrylic resin Substances 0.000 description 2
- 229920000178 Acrylic resin Polymers 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 2
- SOGAXMICEFXMKE-UHFFFAOYSA-N Butylmethacrylate Chemical compound CCCCOC(=O)C(C)=C SOGAXMICEFXMKE-UHFFFAOYSA-N 0.000 description 2
- 239000001856 Ethyl cellulose Substances 0.000 description 2
- ZZSNKZQZMQGXPY-UHFFFAOYSA-N Ethyl cellulose Chemical compound CCOCC1OC(OC)C(OCC)C(OCC)C1OC1C(O)C(O)C(OC)C(CO)O1 ZZSNKZQZMQGXPY-UHFFFAOYSA-N 0.000 description 2
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 2
- 229910018068 Li 2 O Inorganic materials 0.000 description 2
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 2
- 229910006404 SnO 2 Inorganic materials 0.000 description 2
- 238000004220 aggregation Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 229910021419 crystalline silicon Inorganic materials 0.000 description 2
- UYAAVKFHBMJOJZ-UHFFFAOYSA-N diimidazo[1,3-b:1',3'-e]pyrazine-5,10-dione Chemical compound O=C1C2=CN=CN2C(=O)C2=CN=CN12 UYAAVKFHBMJOJZ-UHFFFAOYSA-N 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 235000019325 ethyl cellulose Nutrition 0.000 description 2
- 229920001249 ethyl cellulose Polymers 0.000 description 2
- 239000000383 hazardous chemical Substances 0.000 description 2
- 238000002354 inductively-coupled plasma atomic emission spectroscopy Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000000155 melt Substances 0.000 description 2
- 230000001737 promoting effect Effects 0.000 description 2
- 229940116423 propylene glycol diacetate Drugs 0.000 description 2
- 239000000523 sample Substances 0.000 description 2
- 239000004332 silver Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000004408 titanium dioxide Substances 0.000 description 2
- 238000004017 vitrification Methods 0.000 description 2
- 238000001039 wet etching Methods 0.000 description 2
- LNAZSHAWQACDHT-XIYTZBAFSA-N (2r,3r,4s,5r,6s)-4,5-dimethoxy-2-(methoxymethyl)-3-[(2s,3r,4s,5r,6r)-3,4,5-trimethoxy-6-(methoxymethyl)oxan-2-yl]oxy-6-[(2r,3r,4s,5r,6r)-4,5,6-trimethoxy-2-(methoxymethyl)oxan-3-yl]oxyoxane Chemical compound CO[C@@H]1[C@@H](OC)[C@H](OC)[C@@H](COC)O[C@H]1O[C@H]1[C@H](OC)[C@@H](OC)[C@H](O[C@H]2[C@@H]([C@@H](OC)[C@H](OC)O[C@@H]2COC)OC)O[C@@H]1COC LNAZSHAWQACDHT-XIYTZBAFSA-N 0.000 description 1
- OMIGHNLMNHATMP-UHFFFAOYSA-N 2-hydroxyethyl prop-2-enoate Chemical compound OCCOC(=O)C=C OMIGHNLMNHATMP-UHFFFAOYSA-N 0.000 description 1
- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- WOBHKFSMXKNTIM-UHFFFAOYSA-N Hydroxyethyl methacrylate Chemical compound CC(=C)C(=O)OCCO WOBHKFSMXKNTIM-UHFFFAOYSA-N 0.000 description 1
- VVQNEPGJFQJSBK-UHFFFAOYSA-N Methyl methacrylate Chemical compound COC(=O)C(C)=C VVQNEPGJFQJSBK-UHFFFAOYSA-N 0.000 description 1
- 239000000020 Nitrocellulose Substances 0.000 description 1
- GEIAQOFPUVMAGM-UHFFFAOYSA-N ZrO Inorganic materials [Zr]=O GEIAQOFPUVMAGM-UHFFFAOYSA-N 0.000 description 1
- FJWGYAHXMCUOOM-QHOUIDNNSA-N [(2s,3r,4s,5r,6r)-2-[(2r,3r,4s,5r,6s)-4,5-dinitrooxy-2-(nitrooxymethyl)-6-[(2r,3r,4s,5r,6s)-4,5,6-trinitrooxy-2-(nitrooxymethyl)oxan-3-yl]oxyoxan-3-yl]oxy-3,5-dinitrooxy-6-(nitrooxymethyl)oxan-4-yl] nitrate Chemical compound O([C@@H]1O[C@@H]([C@H]([C@H](O[N+]([O-])=O)[C@H]1O[N+]([O-])=O)O[C@H]1[C@@H]([C@@H](O[N+]([O-])=O)[C@H](O[N+]([O-])=O)[C@@H](CO[N+]([O-])=O)O1)O[N+]([O-])=O)CO[N+](=O)[O-])[C@@H]1[C@@H](CO[N+]([O-])=O)O[C@@H](O[N+]([O-])=O)[C@H](O[N+]([O-])=O)[C@H]1O[N+]([O-])=O FJWGYAHXMCUOOM-QHOUIDNNSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 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
- 238000004458 analytical method Methods 0.000 description 1
- 239000002518 antifoaming agent Substances 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- 229910052785 arsenic Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 125000001797 benzyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C([H])([H])* 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- CQEYYJKEWSMYFG-UHFFFAOYSA-N butyl acrylate Chemical compound CCCCOC(=O)C=C CQEYYJKEWSMYFG-UHFFFAOYSA-N 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 239000001768 carboxy methyl cellulose Substances 0.000 description 1
- 235000010948 carboxy methyl cellulose Nutrition 0.000 description 1
- 239000008112 carboxymethyl-cellulose Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000000110 cooling liquid Substances 0.000 description 1
- 230000001186 cumulative effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 239000007772 electrode material Substances 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- SUPCQIBBMFXVTL-UHFFFAOYSA-N ethyl 2-methylprop-2-enoate Chemical compound CCOC(=O)C(C)=C SUPCQIBBMFXVTL-UHFFFAOYSA-N 0.000 description 1
- 239000005357 flat glass Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 1
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- 229920000609 methyl cellulose Polymers 0.000 description 1
- 239000001923 methylcellulose Substances 0.000 description 1
- 235000010981 methylcellulose Nutrition 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 229920001220 nitrocellulos Polymers 0.000 description 1
- 229940079938 nitrocellulose Drugs 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 238000005268 plasma chemical vapour deposition Methods 0.000 description 1
- 230000000379 polymerizing effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000007650 screen-printing Methods 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
- 238000002834 transmittance Methods 0.000 description 1
- 238000001132 ultrasonic dispersion Methods 0.000 description 1
- 238000001238 wet grinding Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C12/00—Powdered glass; Bead compositions
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C3/00—Glass compositions
- C03C3/04—Glass compositions containing silica
- C03C3/062—Glass compositions containing silica with less than 40% silica by weight
- C03C3/064—Glass compositions containing silica with less than 40% silica by weight containing boron
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C3/00—Glass compositions
- C03C3/12—Silica-free oxide glass compositions
- C03C3/14—Silica-free oxide glass compositions containing boron
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
- H01B1/14—Conductive material dispersed in non-conductive inorganic material
- H01B1/16—Conductive material dispersed in non-conductive inorganic material the conductive material comprising metals or alloys
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/547—Monocrystalline silicon PV cells
Landscapes
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Life Sciences & Earth Sciences (AREA)
- Organic Chemistry (AREA)
- Dispersion Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Glass Compositions (AREA)
- Conductive Materials (AREA)
- Photovoltaic Devices (AREA)
Abstract
Description
本発明は、ガラス組成物、ガラス組成物の製造方法、導電ペースト、及び太陽電池に関する。 The present invention relates to glass compositions, methods for producing glass compositions, conductive pastes, and solar cells.
従来、シリコン（Ｓｉ）等の半導体基板の上に電極となる導電層を形成した電子デバイスが、種々の用途に使用されている。この電極となる導電層は、一般的に、アルミニウム（Ａｌ）や銀（Ａｇ）、銅（Ｃｕ）等の導電性金属粉末とガラス粉末を有機ビヒクル中に分散させた導電ペーストを、半導体基板上に塗布し、導電性金属粉末の融点以上の温度で焼成することにより形成される。 Conventionally, electronic devices in which a conductive layer serving as an electrode is formed on a semiconductor substrate such as silicon (Si) have been used for various purposes. The conductive layer to be the electrode is generally a conductive paste in which conductive metal powder such as aluminum (Al), silver (Ag), copper (Cu) and glass powder are dispersed in an organic vehicle on a semiconductor substrate. It is formed by applying it to and firing it at a temperature equal to or higher than the melting point of the conductive metal powder.
半導体基板上に電極を形成する際には、半導体基板上に絶縁膜を形成し、当該絶縁膜を部分的に貫通して半導体基板に接触するようにしてパターン状の電極を形成する場合がある。例えば、太陽電池においては、半導体基板の受光面上に反射防止膜（絶縁膜）が設けられ、その上にパターン状の電極が設けられる。反射防止膜は、十分な可視光透過率を保ちつつ表面反射率を低減して受光効率を高めるためのものであって、通常、窒化珪素、二酸化チタン、二酸化珪素、酸化アルミニウム等の絶縁材料で構成される。また、ＰＥＲＣ（Passivated Emitter and Rear Contact）等の太陽電池では、裏面にも反射防止膜と同様の絶縁材料からなるパッシベーション膜が設けられ、該パッシベーション膜上に電極が部分的に半導体基板に接触するように形成される。 When forming an electrode on a semiconductor substrate, an insulating film may be formed on the semiconductor substrate, and a patterned electrode may be formed so as to partially penetrate the insulating film and come into contact with the semiconductor substrate. .. For example, in a solar cell, an antireflection film (insulating film) is provided on a light receiving surface of a semiconductor substrate, and a patterned electrode is provided on the antireflection film (insulating film). The antireflection film is for reducing the surface reflectance and increasing the light receiving efficiency while maintaining sufficient visible light transmittance, and is usually made of an insulating material such as silicon nitride, titanium dioxide, silicon dioxide, or aluminum oxide. It is composed. Further, in a solar cell such as PERC (Passivated Emitter and Rear Contact), a passivation film made of an insulating material similar to an antireflection film is provided on the back surface, and an electrode partially contacts a semiconductor substrate on the passivation film. Is formed as follows.
電極は、半導体基板に接触するように形成する必要がある。したがって、電極形成の際には、形成する電極のパターンに応じて絶縁膜が部分的に除去され、絶縁膜が除去された部分に電極が形成される。
絶縁層を部分的に除去する方法としてレーザー等で物理的に除去する方法が挙げられるが、当該方法は製造工程の増加や、装置導入コストの増加を伴う。したがって、近年では導電性金属粉末とガラス粉末を含有する導電ペースト（ペースト状の電極材料）を絶縁膜上に塗布して熱処理を行うことで、該導電ペーストに絶縁膜を貫通させる方法（ファイヤースルー）が採用されている。
The electrodes need to be formed so as to be in contact with the semiconductor substrate. Therefore, when forming the electrode, the insulating film is partially removed according to the pattern of the electrode to be formed, and the electrode is formed in the portion from which the insulating film has been removed.
As a method of partially removing the insulating layer, a method of physically removing the insulating layer with a laser or the like can be mentioned, but this method involves an increase in a manufacturing process and an increase in equipment introduction cost. Therefore, in recent years, a method (fire-through) in which a conductive paste (paste-like electrode material) containing a conductive metal powder and a glass powder is applied onto an insulating film and heat-treated to allow the conductive paste to penetrate the insulating film. ) Is adopted.
ファイヤースルーに用いる導電ペーストとしては様々なものが開発されており、例えば特許文献１には、所定量のアルミニウム粉末、ガラス粉末、銀、有機ビヒクルを含む裏面電極用ペーストが開示されている。また、特許文献２には、所定の形状のアルミニウム粉末と、有機ビヒクルと、Ｂｉ２Ｏ３−ＺｎＯ−Ｂ２Ｏ３−ＣｕＯを含むガラス粉末を含むペースト組成物が開示されている。 Various conductive pastes used for fire-through have been developed. For example, Patent Document 1 discloses a paste for a back electrode containing a predetermined amount of aluminum powder, glass powder, silver, and an organic vehicle. Further, Patent Document 2 discloses a paste composition containing an aluminum powder having a predetermined shape, an organic vehicle, and a glass powder containing Bi 2 O 3- ZnO-B 2 O 3- CuO.
本願発明者らは特許文献１に開示された裏面ペーストを用いて裏面パッシベーション層を貫通する裏面電極を形成することを試みた。しかしながら、当該裏面ペーストはファイヤースルー性が低く、良好なｐ＋層が得られなかった。また、特許文献２に開示された裏面ペーストはＣｕＯを必須成分として含むが、Ｃｕは半導体基板の材料であるシリコン中を拡散しやすいので、太陽電池の電気特性を悪化させやすい。 The inventors of the present application have attempted to form a back surface electrode penetrating the back surface passivation layer using the back surface paste disclosed in Patent Document 1. However, the backside paste had low fire-through property, and a good p + layer could not be obtained. Further, the back surface paste disclosed in Patent Document 2 contains CuO as an essential component, but since Cu easily diffuses in silicon, which is a material of a semiconductor substrate, it tends to deteriorate the electrical characteristics of a solar cell.
上記に鑑みて、本発明は、導電性金属粉末と有機ビヒクルと混合してペースト化することにより、ファイヤースルー性が高くさらに半導体基板を劣化させることがない導電ペーストを得られるガラス組成物を提供することを目的とする。
また、本発明は、導電性金属粉末と有機ビヒクルと混合してペースト化することにより、ファイヤースルー性が高くさらに半導体基板を劣化させることがない導電ペーストを得られるガラス組成物の製造方法を提供することを目的とする。
また、本発明は、ファイヤースルー性が高くさらに半導体基板を劣化させることがない導電ペーストを提供することを目的とする。
また、本発明はファイヤースルー性が高くさらに半導体基板を劣化させることがない導電ペーストにより形成された電極を備える太陽電池を提供することを目的とする。
In view of the above, the present invention provides a glass composition capable of obtaining a conductive paste having high fire-through property and not deteriorating the semiconductor substrate by mixing the conductive metal powder and the organic vehicle to form a paste. The purpose is to do.
The present invention also provides a method for producing a glass composition, which can obtain a conductive paste having high fire-through property and not deteriorating a semiconductor substrate by mixing and forming a paste by mixing a conductive metal powder and an organic vehicle. The purpose is to do.
Another object of the present invention is to provide a conductive paste having high fire-through property and not deteriorating a semiconductor substrate.
Another object of the present invention is to provide a solar cell including an electrode formed of a conductive paste having high fire-through property and not deteriorating a semiconductor substrate.
本発明は以下の構成のガラス組成物、ガラス組成物の製造方法、導電ペーストおよび太陽電池を提供する。
［１］酸化物基準のモル％表記で、Ｂｉ２Ｏ３を３％以上１９％以下、Ｂ２Ｏ３を２０％以上７０％以下、ＳｉＯ２を１％以上３０％以下、Ｋ２Ｏを３％以上２０％以下、ＣａＯを３％以上２０％以下、ＢａＯを１％以上２０％以下、含有し、実質的にＰｂＯとＣｕＯとを含まないガラス組成物。
［２］さらに、酸化物基準のモル％表記で、ＳｒＯ、およびＺｎＯから選ばれる少なくとも１種を合計で０％以上１５％以下含有する［１］に記載のガラス組成物。
［３］酸化物基準のモル％表記で、Ｂ２Ｏ３を３５％以上６０％以下、Ｋ２Ｏを１％以上４０％以下、ＣａＯを３％以上３０％以下、ＢａＯを２％以上２５％以下、ＳｉＯ２を５％以上１０％以下含有し、実質的にＰｂＯとＣｕＯとを含まない第１のガラス組成物と、酸化物基準のモル％表記で、Ｂｉ２Ｏ３を５％以上６０％以下、Ｂ２Ｏ３を１５％以上８０％以下含有し、実質的にＰｂＯとＣｕＯとを含まない第２のガラス組成物とを混合する工程を含む、ガラス組成物の製造方法。
［４］前記第１のガラス組成物が、さらに酸化物基準のモル％表記でＳｒＯを０％以上１５％以下含有する［３］に記載のガラス組成物の製造方法。
［５］前記第２のガラス組成物が、さらに酸化物基準のモル％表記でＺｎＯを０％以上３０％以下含有する［３］または［４］に記載のガラス組成物の製造方法。
［６］前記第１のガラス組成物と前記第２のガラス組成物の混合割合が質量比で８０：２０〜４０：６０である［３］〜［５］のいずれか１つに記載のガラス組成物の製造方法。
［７］［１］または［２］に記載のガラス組成物の製造方法である、［３］〜［６］のいずれか１つに記載のガラス組成物の製造方法。
［８］酸化物基準のモル％表記で、Ｂｉ２Ｏ３を３％以上１９％以下、Ｂ２Ｏ３を２０％以上７０％以下、ＳｉＯ２を１％以上３０％以下、Ｋ２Ｏを３％以上２０％以下、ＣａＯを３％以上２０％以下、ＢａＯを１％以上２０％以下含有し、実質的にＰｂＯとＣｕＯとを含まないガラスの粉末と、導電性金属粉末と、有機ビヒクルとを含有する導電ペースト。
［９］［８］に記載の導電ペーストを用いて形成された電極を具備する太陽電池。
［１０］太陽光受光面を有するシリコン基板と、前記シリコン基板の前記太陽光受光面に設けられた第１の絶縁膜と、前記シリコン基板の前記太陽光受光面とは反対側の面に設けられた第２の絶縁膜と、前記第１の絶縁膜の一部を貫通して前記シリコン基板に接触する第１の電極と、前記第２の絶縁膜の一部を貫通して前記シリコン基板に接触する第２の電極と、を備える太陽電池であって、前記第１の電極は、Ａｌ、Ａｇ、Ｃｕ、Ａｕ、ＰｄおよびＰｔからなる群から選択される少なくとも１種を含む第１の金属と、第１のガラスとを含み、前記第２の電極は、Ａｌ、Ａｇ、Ｃｕ、Ａｕ、ＰｄおよびＰｔからなる群から選択される少なくとも１種を含む第２の金属と、酸化物基準のモル％表記で、Ｂｉ２Ｏ３を３％以上１９％以下、Ｂ２Ｏ３を２０％以上７０％以下、ＳｉＯ２を１％以上３０％以下、Ｋ２Ｏを３％以上２０％以下、ＣａＯを３％以上２０％以下、ＢａＯを１％以上２０％以下、含有し、実質的にＰｂＯとＣｕＯとを含まない第２のガラスを含む太陽電池。
［１１］前記第２の電極は、前記第２の金属１００質量部に対して、前記第２のガラスを０．１質量部以上１５質量部以下含む［１０］に記載の太陽電池。
［１２］前記第２の金属はＡｇを含む［１０］または［１１］に記載の太陽電池。
［１３］前記第２の金属はＡｌを含む［１０］〜［１２］のいずれか１つに記載の太陽電池。
The present invention provides a glass composition having the following constitution, a method for producing the glass composition, a conductive paste, and a solar cell.
[1] Bi 2 O 3 is 3% or more and 19% or less, B 2 O 3 is 20% or more and 70% or less, SiO 2 is 1% or more and 30% or less, and K 2 O is K 2 O in mol% notation based on oxides. A glass composition containing 3% or more and 20% or less, CaO of 3% or more and 20% or less, BaO of 1% or more and 20% or less, and substantially free of PbO and CuO.
[2] The glass composition according to [1], further containing at least one selected from SrO and ZnO in a total of 0% or more and 15% or less in terms of oxide-based molar%.
[3] B 2 O 3 is 35% or more and 60% or less, K 2 O is 1% or more and 40% or less, Ca O is 3% or more and 30% or less, and Ba O is 2% or more and 25% or less in terms of oxide-based mol%. % Or less, 5% or more and 10% or less of SiO 2, and 5% or more of Bi 2 O 3 in terms of oxide-based molar% with the first glass composition containing substantially no PbO and CuO. A method for producing a glass composition, which comprises a step of mixing a second glass composition containing 60% or less, B 2 O 3 of 15% or more and 80% or less, and substantially free of PbO and CuO.
[4] The method for producing a glass composition according to [3], wherein the first glass composition further contains SrO of 0% or more and 15% or less in terms of molar% based on oxides.
[5] The method for producing a glass composition according to [3] or [4], wherein the second glass composition further contains ZnO of 0% or more and 30% or less in terms of molar% based on oxides.
[6] The glass according to any one of [3] to [5], wherein the mixing ratio of the first glass composition and the second glass composition is 80:20 to 40:60 in mass ratio. Method for producing the composition.
[7] The method for producing a glass composition according to any one of [3] to [6], which is the method for producing a glass composition according to [1] or [2].
[8] Bi 2 O 3 is 3% or more and 19% or less, B 2 O 3 is 20% or more and 70% or less, SiO 2 is 1% or more and 30% or less, and K 2 O is K 2 O in mol% notation based on oxides. A glass powder containing 3% or more and 20% or less, CaO of 3% or more and 20% or less, BaO of 1% or more and 20% or less, and substantially free of PbO and CuO, a conductive metal powder, and an organic vehicle. Conductive paste containing and.
[9] A solar cell including an electrode formed by using the conductive paste according to [8].
[10] A silicon substrate having a solar light receiving surface, a first insulating film provided on the solar light receiving surface of the silicon substrate, and a surface of the silicon substrate opposite to the solar light receiving surface. The second insulating film, the first electrode that penetrates a part of the first insulating film and contacts the silicon substrate, and the silicon substrate that penetrates a part of the second insulating film and contacts the silicon substrate. A solar cell comprising a second electrode in contact with, said first electrode comprising at least one selected from the group consisting of Al, Ag, Cu, Au, Pd and Pt. The second electrode contains a metal and a first glass, and the second electrode contains a second metal containing at least one selected from the group consisting of Al, Ag, Cu, Au, Pd and Pt, and an oxide reference. Bi 2 O 3 is 3% or more and 19% or less, B 2 O 3 is 20% or more and 70% or less, SiO 2 is 1% or more and 30% or less, and K 2 O is 3% or more and 20% or less. , A solar cell containing a second glass containing CaO of 3% or more and 20% or less, BaO of 1% or more and 20% or less, and substantially free of PbO and CuO.
[11] The solar cell according to [10], wherein the second electrode contains 0.1 part by mass or more and 15 parts by mass or less of the second glass with respect to 100 parts by mass of the second metal.
[12] The solar cell according to [10] or [11], wherein the second metal contains Ag.
[13] The solar cell according to any one of [10] to [12], wherein the second metal contains Al.
本発明のガラス組成物は、導電性金属粉末と有機ビヒクルと混合してペースト化することにより、ファイヤースルー性が高くさらに半導体基板を劣化させることがない導電ペーストを得られる。
また、本発明のガラス組成物の製造方法は、導電性金属粉末と有機ビヒクルと混合してペースト化することにより、ファイヤースルー性が高くさらに半導体基板を劣化させることがない導電ペーストを得られるガラス組成物の製造方法を提供する。
また、本発明の導電ペーストは、ファイヤースルー性が高くさらに半導体基板を劣化させることがない。
また、本発明の太陽電池はファイヤースルー性が高くさらに半導体基板を劣化させることがない導電ペーストにより形成された電極を備える太陽電池であり、信頼性と生産性に優れる。
By mixing the conductive metal powder and the organic vehicle into a paste, the glass composition of the present invention can obtain a conductive paste having high fire-through property and not deteriorating the semiconductor substrate.
Further, in the method for producing a glass composition of the present invention, a conductive paste having high fire-through property and not deteriorating a semiconductor substrate can be obtained by mixing a conductive metal powder and an organic vehicle to form a paste. A method for producing a composition is provided.
Further, the conductive paste of the present invention has high fire-through property and does not further deteriorate the semiconductor substrate.
Further, the solar cell of the present invention is a solar cell having an electrode formed of a conductive paste which has high fire-through property and does not deteriorate the semiconductor substrate, and is excellent in reliability and productivity.
以下、本発明の実施形態について説明する。
なお、本明細書において、ガラスの組成について「モル％」又は単に「％」というときは、酸化物基準のモル％を意味する。
また、本明細書において、実質的に含有しないとは、積極的には含有させないが、不可避不純物による混入を許容することを意味する。
＜１．ガラス組成物＞
まず、本発明において提供されるガラス組成物について説明する。
本発明のガラス組成物はモル％表示で、Ｂｉ２Ｏ３を３％以上１９％以下、Ｂ２Ｏ３を２０％以上７０％以下、ＳｉＯ２を１％以上３０％以下、Ｋ２Ｏを３％以上２０％以下、ＣａＯを３％以上２０％以下、ＢａＯを１％以上２０％以下含有し、実質的にＰｂＯとＣｕＯとを含まない。
なお、本発明のガラス組成物における各成分の含有量は、誘導結合プラズマ発光分析（ＩＣＰ−ＡＥＳ：Inductively Coupled Plasma-Atomic Emission Spectroscopy）、または電子線マイクロアナライザ（ＥＰＭＡ：Electron Probe Micro Analyzer）分析の結果から求められる。
Hereinafter, embodiments of the present invention will be described.
In the present specification, when the composition of glass is referred to as "mol%" or simply "%", it means an oxide-based mol%.
Further, in the present specification, substantially not contained means that the mixture is not positively contained, but is allowed to be mixed by unavoidable impurities.
<1. Glass composition>
First, the glass composition provided in the present invention will be described.
The glass composition of the present invention contains Bi 2 O 3 of 3% or more and 19% or less, B 2 O 3 of 20% or more and 70% or less, SiO 2 of 1% or more and 30% or less, and K 2 O in mol%. It contains 3% or more and 20% or less, CaO of 3% or more and 20% or less, BaO of 1% or more and 20% or less, and substantially does not contain PbO and CuO.
The content of each component in the glass composition of the present invention is determined by inductively coupled plasma-Atomic Emission Spectroscopy (ICP-AES) or electron probe microanalyzer (EPMA) analysis. Obtained from the results.
上記組成を有する本発明のガラス組成物を導電性金属粉末及び有機ビヒクルと混合してペースト化すると、ファイヤースルー性が高くさらに半導体基板を劣化させることがない導電ペーストを得られる。より詳細には、本発明のガラス組成物を含む導電ペーストを焼成すると、比較的早い段階でガラス組成物が流動して絶縁膜と反応し、絶縁膜を貫通する。また、更に温度が上がるとガラス組成物が半導体基板中への電極の侵入を促進させ、これにより半導体基板と十分な接触を有する信頼性の高い絶縁膜貫通電極が形成される。このように本発明のガラス組成物を含む導電ペーストを用いると、レーザー等で絶縁膜を物理的に除去してから電極を形成する方法に比べて、高効率、低コストで絶縁膜貫通電極を形成できる。 When the glass composition of the present invention having the above composition is mixed with the conductive metal powder and the organic vehicle to form a paste, a conductive paste having high fire-through property and not deteriorating the semiconductor substrate can be obtained. More specifically, when the conductive paste containing the glass composition of the present invention is fired, the glass composition flows at a relatively early stage, reacts with the insulating film, and penetrates the insulating film. Further, when the temperature is further raised, the glass composition promotes the penetration of the electrode into the semiconductor substrate, whereby a highly reliable insulating film through electrode having sufficient contact with the semiconductor substrate is formed. As described above, when the conductive paste containing the glass composition of the present invention is used, the insulating film penetrating electrode can be obtained with high efficiency and low cost as compared with the method of forming the electrode after physically removing the insulating film with a laser or the like. Can be formed.
以下、本発明のガラス組成物に含有される成分について説明する。 Hereinafter, the components contained in the glass composition of the present invention will be described.
Ｂｉ２Ｏ３は、ガラス組成物の軟化時の流動性を向上させ、また、ガラス転移点を低下させることにより、ガラス組成物と絶縁膜との反応性を向上させる成分である。
本発明のガラス組成物のＢｉ２Ｏ３の含有量が３％未満であると、ガラス組成物の流動性が低下し、ガラス組成物と絶縁膜との反応性が低下する。したがって、本発明のガラス組成物のＢｉ２Ｏ３の含有量は３％以上、好ましくは５％以上、より好ましくは８％以上である。
一方、本発明のガラス組成物のＢｉ２Ｏ３の含有量が１９％超であると、結晶化によりガラス組成物が得られない恐れがある。したがって、本発明のガラス組成物のＢｉ２Ｏ３の含有量は１９％以下、好ましくは１５％以下、より好ましくは１３％以下である。
Bi 2 O 3 is a component that improves the reactivity of the glass composition and the insulating film by improving the fluidity of the glass composition during softening and lowering the glass transition point.
When the content of Bi 2 O 3 in the glass composition of the present invention is less than 3%, the fluidity of the glass composition is lowered and the reactivity between the glass composition and the insulating film is lowered. Therefore, the content of Bi 2 O 3 in the glass composition of the present invention is 3% or more, preferably 5% or more, and more preferably 8% or more.
On the other hand, if the content of Bi 2 O 3 in the glass composition of the present invention is more than 19%, the glass composition may not be obtained due to crystallization. Therefore, the content of Bi 2 O 3 in the glass composition of the present invention is 19% or less, preferably 15% or less, and more preferably 13% or less.
Ｂ２Ｏ３は、ガラス組成物の軟化時の流動性を向上させ、半導体基板との接合強度を向上させる成分である。また、Ｂ２Ｏ３はガラスの網目構造形成成分であり、ガラス組成物の安定化に寄与する成分でもある。更に、Ｂ２Ｏ３は半導体基板とガラス組成物の反応を促進する成分でもあり、例えば、半導体基板がｐｎ接合型のＳｉ半導体基板である場合、電極と接触するｐ＋層やｎ＋層の良好な形成を促進する。例えば、ｐ＋層に接触する電極を形成する際には、Ｂ２Ｏ３中のＢがｐ＋層に拡散し、より良好なｐ＋層の形成に寄与する。
本発明のガラス組成物のＢ２Ｏ３の含有量が２０％未満であると、ガラス組成物の安定性が低下してガラス化できない恐れがあり、また、上記の半導体基板とガラス組成物の反応の促進効果が十分に得られない恐れがある。したがって、本発明のガラス組成物のＢ２Ｏ３の含有量は２０％以上、好ましくは２５％以上、より好ましくは３５％以上である。
一方、本発明のガラス組成物のＢ２Ｏ３の含有量が７０％超であると、ガラス組成物の耐候性が劣化する恐れがある。したがって、本発明のガラス組成物のＢ２Ｏ３の含有量は７０％以下、好ましくは６０％以下、より好ましくは５５％以下である。
B 2 O 3 is a component that improves the fluidity of the glass composition during softening and improves the bonding strength with the semiconductor substrate. In addition, B 2 O 3 is a network structure forming component of glass, and is also a component that contributes to stabilization of the glass composition. Further, B 2 O 3 is also a component that promotes the reaction between the semiconductor substrate and the glass composition. For example, when the semiconductor substrate is a pn junction type Si semiconductor substrate, the p + layer or n + layer in contact with the electrode Promotes good formation. For example, when forming the electrode in contact with p + layer, B in B 2 O 3 is diffused in the p + layer, contribute to the formation of better p + layer.
If the content of B 2 O 3 in the glass composition of the present invention is less than 20%, the stability of the glass composition may decrease and vitrification may not be possible, and the above-mentioned semiconductor substrate and glass composition may not be vitrified. The effect of promoting the reaction may not be sufficiently obtained. Therefore, the content of B 2 O 3 in the glass composition of the present invention is 20% or more, preferably 25% or more, and more preferably 35% or more.
On the other hand, if the content of B 2 O 3 in the glass composition of the present invention exceeds 70%, the weather resistance of the glass composition may deteriorate. Therefore, the content of B 2 O 3 in the glass composition of the present invention is 70% or less, preferably 60% or less, and more preferably 55% or less.
ＳｉＯ２は、ガラス組成物の耐候性の向上及び安定性の向上に寄与する成分である。
本発明のガラス組成物のＳｉＯ２の含有量が１％未満であると、結晶化によりガラス組成物が得られない恐れがある。したがって、本発明のガラス組成物のＳｉＯ２の含有量は１％以上、好ましくは３％以上である。
一方、本発明のガラス組成物のＳｉＯ２の含有量が３０％超であると、ガラス転移点が高くなり、ガラス組成物が流動しにくくなる恐れがある。したがって、本発明のガラス組成物のＳｉＯ２の含有量は３０％以下、好ましくは２０％以下、より好ましくは１０％以下である。
SiO 2 is a component that contributes to the improvement of weather resistance and the improvement of stability of the glass composition.
If the content of SiO 2 in the glass composition of the present invention is less than 1%, the glass composition may not be obtained due to crystallization. Therefore, the content of SiO 2 in the glass composition of the present invention is 1% or more, preferably 3% or more.
On the other hand, if the content of SiO 2 in the glass composition of the present invention is more than 30%, the glass transition point becomes high and the glass composition may not flow easily. Therefore, the content of SiO 2 in the glass composition of the present invention is 30% or less, preferably 20% or less, and more preferably 10% or less.
Ｋ２Ｏは、ガラス組成物の軟化時の流動性を向上させ、半導体基板と電極の接合強度を向上させる成分である。また、Ｋ２Ｏに含まれるＫは、絶縁膜を貫通して半導体基板と接触した際に半導体基板中に移動しやすく、したがって、例えば導電性金属がＡｌの場合、Ａｌ粒子のＳｉ半導体基板への拡散するのを助けることができる。このことから、Ｋ２Ｏは電極と半導体基板との間の接触抵抗を下げる成分であり、また、良好なｐ＋層の形成に寄与する成分である。
本発明のガラス組成物のＫ２Ｏの含有量が３％未満であると、ガラス転移点が高くなり、ガラスが流動しにくくなる恐れがある。したがって、本発明のガラス組成物のＫ２Ｏの含有量は３％以上、好ましくは５％以上、より好ましくは８％以上である。
一方、本発明のガラス組成物のＫ２Ｏの含有量が２０％超であると、結晶化によりガラス組成物が得られない恐れがある。したがって、本発明のガラス組成物のＫ２Ｏの含有量は２０％以下、好ましくは１８％以下である。
K 2 O is a component that improves the fluidity of the glass composition during softening and improves the bonding strength between the semiconductor substrate and the electrode. Further, K contained in K 2 O easily moves into the semiconductor substrate when it penetrates the insulating film and comes into contact with the semiconductor substrate. Therefore, for example, when the conductive metal is Al, it moves to the Si semiconductor substrate of Al particles. Can help spread. From this, K 2 O is a component that lowers the contact resistance between the electrode and the semiconductor substrate, and is a component that contributes to the formation of a good p + layer.
If the K 2 O content of the glass composition of the present invention is less than 3%, the glass transition point becomes high and the glass may not flow easily. Therefore, the K 2 O content of the glass composition of the present invention is 3% or more, preferably 5% or more, more preferably 8% or more.
On the other hand, when the content of K 2 O of the glass composition of the present invention is 20 percent, there may not glass composition is obtained by crystallization. Therefore, the K 2 O content of the glass composition of the present invention is 20% or less, preferably 18% or less.
ＣａＯは、電極と半導体基板との接触抵抗の低下に寄与する成分である。ＣａＯは熱が加わることにより結晶核を形成し、結晶粒を成長させることにより絶縁膜の貫通を促進する。
本発明のガラス組成物のＣａＯの含有量が３％未満であると、絶縁膜の貫通が不十分となる恐れがある。したがって、本発明のガラス組成物のＣａＯの含有量は３％以上、好ましくは４％以上である。
一方、本発明のガラス組成物のＣａＯの含有量が２０％超であると、結晶化によりガラス組成物が得られない恐れがある。したがって、本発明のガラス組成物のＣａＯの含有量は２０％以下、好ましくは１８％以下である。
CaO is a component that contributes to a decrease in contact resistance between the electrode and the semiconductor substrate. CaO forms crystal nuclei when heat is applied, and promotes penetration of the insulating film by growing crystal grains.
If the CaO content of the glass composition of the present invention is less than 3%, the penetration of the insulating film may be insufficient. Therefore, the CaO content of the glass composition of the present invention is 3% or more, preferably 4% or more.
On the other hand, if the CaO content of the glass composition of the present invention is more than 20%, the glass composition may not be obtained due to crystallization. Therefore, the CaO content of the glass composition of the present invention is 20% or less, preferably 18% or less.
ＢａＯは、電極と半導体基板との接触抵抗の低下に寄与する成分である。
本発明のガラス組成物のＢａＯの含有量が１％未満であると、ガラス転移点が高くなり、ガラス組成物が流動しにくくなる恐れがある。したがって、本発明のガラス組成物のＢａＯの含有量は１％以上、好ましくは４％以上である。
一方、本発明のガラス組成物のＢａＯの含有量が２０％超であると、結晶化によりガラス組成物が得られない恐れがある。したがって、本発明のガラス組成物のＢａＯの含有量は２０％以下、好ましくは１８％以下、より好ましくは１５％以下である。
BaO is a component that contributes to a decrease in contact resistance between the electrode and the semiconductor substrate.
If the BaO content of the glass composition of the present invention is less than 1%, the glass transition point becomes high and the glass composition may not flow easily. Therefore, the content of BaO in the glass composition of the present invention is 1% or more, preferably 4% or more.
On the other hand, if the BaO content of the glass composition of the present invention is more than 20%, the glass composition may not be obtained due to crystallization. Therefore, the content of BaO in the glass composition of the present invention is 20% or less, preferably 18% or less, and more preferably 15% or less.
本発明のガラス組成物は、本発明の効果を奏する限りにおいて上記成分以外の成分を含有してもよい。例えば、本発明のガラス組成物は、さらに、ＳｒＯ、およびＺｎＯから選ばれる少なくとも１種を含有してもよい。これらの成分は、ガラスの安定性や耐候性の向上に寄与する成分である。本発明のガラス組成物にＳｒＯ、およびＺｎＯから選ばれる少なくとも１種を含有させる場合の含有量は、合計で０．５％以上が好ましい。
一方、本発明のガラス組成物をガラス化しやすくするためには、本発明のガラス組成物にＳｒＯ、およびＺｎＯから選ばれる少なくとも１種を含有させる場合の含有量は、合計で１５％以下が好ましく、１３％以下がより好ましい。
The glass composition of the present invention may contain components other than the above components as long as the effects of the present invention are exhibited. For example, the glass composition of the present invention may further contain at least one selected from SrO and ZnO. These components are components that contribute to improving the stability and weather resistance of glass. When the glass composition of the present invention contains at least one selected from SrO and ZnO, the total content is preferably 0.5% or more.
On the other hand, in order to facilitate vitrification of the glass composition of the present invention, the total content of the glass composition of the present invention is preferably 15% or less when at least one selected from SrO and ZnO is contained. , 13% or less is more preferable.
また、本発明のガラス組成物は他にも例えばＰ２Ｏ５、Ａｓ２Ｏ５、ＭｇＯ、Ｌｉ２Ｏ、Ｎａ２Ｏ、ＺｒＯ２、Ａｌ２Ｏ３、Ｆｅ２Ｏ３、Ｓｂ２Ｏ３、Ｓｂ２Ｏ５、ＳｎＯ２、ＭｏＯ３、ＷＯ３、ＭｎＯ、ＭｎＯ２、ＣｅＯ２、ＴｉＯ２等の通常ガラスに用いられる酸化物成分を含有してもよい。これらの酸化物成分は目的に応じて、１種を単独で、または２種以上を組み合せて用いることができる。これらの酸化物成分の含有量は合計で５％以下が好ましい。 In addition, the glass composition of the present invention also includes, for example, P 2 O 5 , As 2 O 5 , MgO, Li 2 O, Na 2 O, ZrO 2 , Al 2 O 3 , Fe 2 O 3 , Sb 2 O 3. , Sb 2 O 5 , SnO 2 , MoO 3 , WO 3 , MnO, MnO 2 , CeO 2 , TiO 2, and other oxide components commonly used in glass may be contained. These oxide components may be used alone or in combination of two or more, depending on the purpose. The total content of these oxide components is preferably 5% or less.
ＰｂＯは、環境負荷物質としてＲｏＨＳ規制などにより禁止される、或いは、規制外の用途においても使用が敬遠されている成分である。
したがって、本発明のガラス組成物にはＰｂＯを添加しない。すなわち、本発明のガラス組成物はＰｂＯを実質的に含有しない。なお、本発明のガラス組成物にはＰｂＯが不純物として含まれる場合がある。本発明のガラス組成物のＰｂＯの含有量は、好ましくは０．１％以下である。
PbO is a component that is prohibited as an environmentally hazardous substance by RoHS regulations or the like, or its use is avoided even in non-regulated applications.
Therefore, PbO is not added to the glass composition of the present invention. That is, the glass composition of the present invention does not substantially contain PbO. The glass composition of the present invention may contain PbO as an impurity. The PbO content of the glass composition of the present invention is preferably 0.1% or less.
ＣｕＯは半導体基板中を拡散して半導体基板の特性を劣化させやすい成分である。
したがって、本発明のガラス組成物にはＣｕＯを添加しない。すなわち、本発明のガラス組成物はＣｕＯを実質的に含有しない。なお、本発明のガラス組成物にはＣｕＯが不純物として含まれる場合がある。本発明のガラス組成物のＣｕＯの含有量は、好ましくは０．１％以下である。
CuO is a component that easily diffuses in the semiconductor substrate and deteriorates the characteristics of the semiconductor substrate.
Therefore, CuO is not added to the glass composition of the present invention. That is, the glass composition of the present invention does not substantially contain CuO. The glass composition of the present invention may contain CuO as an impurity. The CuO content of the glass composition of the present invention is preferably 0.1% or less.
本発明のガラス組成物は、単一種のガラス組成物からなってもよく、また、組成の異なる複数種のガラス組成物の混合物であってもよい。混合物である場合は、平均組成が上記の組成範囲の条件を満足すればよい。
例えば本発明のガラス組成物は、後述の第１のガラス組成物と第２のガラス組成物を、平均組成が上記の組成範囲の条件を満足するように混合した混合物であってもよい。本発明のガラス組成物が後述の第１のガラス組成物と第２のガラス組成物の混合物である場合、第１のガラス組成物と第２のガラス組成物の混合割合は、質量比で８０：２０〜４０：６０が好ましく、７５：２５〜４５：５５がより好ましい。
The glass composition of the present invention may consist of a single type of glass composition, or may be a mixture of a plurality of types of glass compositions having different compositions. In the case of a mixture, the average composition may satisfy the conditions of the above composition range.
For example, the glass composition of the present invention may be a mixture of the first glass composition and the second glass composition, which will be described later, so that the average composition satisfies the conditions of the above composition range. When the glass composition of the present invention is a mixture of the first glass composition and the second glass composition described later, the mixing ratio of the first glass composition and the second glass composition is 80 by mass ratio. : 20 to 40:60 is preferable, and 75:25 to 45:55 is more preferable.
本発明のガラス組成物の形状は特に限定されず、例えば粒上、薄板状（フレーク状）、粉状などであってよいが、ペースト化される際の分散性を向上させるためには粉状であることが好ましい。
本発明のガラス組成物が粉状である場合は、体積基準の５０％粒径Ｄ５０が０．５μｍ以上１０μｍ以下であることが好ましい。Ｄ５０が０．５μｍ以上であると、ペースト化される際の分散性が向上する。Ｄ５０が１０μｍ以下であると、本発明のガラス組成物を含むペースト内において導電性金属粉末の周りにガラスが存在しない個所が発生しにくくなり、得られる電極と半導体基板との接着性が特に良好になる。Ｄ５０は、より好ましくは７．０μｍ以下である。
なお、本明細書においてＤ５０は、レーザー回折／散乱式粒度分布測定装置を用いて測定した粒径分布の累積粒度曲線において、その積算量が体積基準で５０％を占めるときの粒径を意味する。
The shape of the glass composition of the present invention is not particularly limited, and may be, for example, on the grain, in the form of a thin plate (flake), in the form of powder, etc. Is preferable.
When the glass composition of the present invention is in the form of powder, it is preferable that the volume-based 50% particle size D 50 is 0.5 μm or more and 10 μm or less. When D 50 is 0.5 μm or more, the dispersibility at the time of pasting is improved. When D 50 is 10 μm or less, it is difficult for places where glass does not exist around the conductive metal powder in the paste containing the glass composition of the present invention, and the adhesiveness between the obtained electrode and the semiconductor substrate is particularly high. Become good. D 50 is more preferably 7.0 μm or less.
In the present specification, D 50 means the particle size when the integrated amount occupies 50% on a volume basis in the cumulative particle size curve of the particle size distribution measured by using the laser diffraction / scattering type particle size distribution measuring device. To do.
本発明のガラス組成物は完全に非晶質であること、すなわち結晶化度が０％であることが好ましいが、本発明の効果を奏する範囲であれば、結晶化した部分を含んでいても、すなわち結晶化度が０％超であってもよい。 It is preferable that the glass composition of the present invention is completely amorphous, that is, the crystallinity is 0%, but the glass composition of the present invention may contain a crystallized portion as long as the effect of the present invention is exhibited. That is, the crystallinity may be more than 0%.
上記の本発明のガラス組成物は、例えば以下の方法により得られる。 The above-mentioned glass composition of the present invention can be obtained, for example, by the following method.
まず、所望の組成範囲となるようにガラス原料を混合して原料混合物を得る。ガラス原料は、通常の酸化物系のガラスの製造に用いる原料であれば特に限定されず、酸化物や炭酸塩等を用いることができる。 First, the glass raw materials are mixed so as to have a desired composition range to obtain a raw material mixture. The glass raw material is not particularly limited as long as it is a raw material used for producing ordinary oxide-based glass, and oxides, carbonates, and the like can be used.
次に、原料混合物を加熱して溶融物を得る。この際の加熱温度（溶融温度）は、８００〜１５００℃が好ましく、９００〜１４００℃がより好ましい。加熱時間は、３０〜３００分が好ましい。 The raw material mixture is then heated to obtain a melt. The heating temperature (melting temperature) at this time is preferably 800 to 1500 ° C, more preferably 900 to 1400 ° C. The heating time is preferably 30 to 300 minutes.
その後、溶融物を冷却し固化することにより、ガラス組成物を得る。冷却方法は特に限定されない。ロールアウトマシン、プレスマシン、冷却液体への滴下等により急冷する方法をとることもできる。このようにして得られるガラス組成物の形状は特に限定されず、例えば、ブロック状、板状、薄い板状（フレーク状）、粉末状等であってもよい。また、この後ガラス組成物に必要に応じて形状を整えるための処理を施してもよい。
例えば、粉状のガラス組成物を得たい場合は、乾式粉砕法や湿式粉砕法によってガラス組成物を粉砕すればよい。湿式粉砕法の場合、溶媒として水を用いることが好ましい。粉砕は、例えばロールミル、ボールミル、ジェットミル等の粉砕機を用いて行うことができる。また、粉砕後に必要に応じて分級することにより、粉状のガラス組成物の粒径（Ｄ５０）を調整することができる。
Then, the melt is cooled and solidified to obtain a glass composition. The cooling method is not particularly limited. It is also possible to take a method of quenching by a roll-out machine, a press machine, dropping onto a cooling liquid, or the like. The shape of the glass composition thus obtained is not particularly limited, and may be, for example, a block shape, a plate shape, a thin plate shape (flake shape), a powder shape, or the like. Further, after that, the glass composition may be subjected to a treatment for adjusting the shape, if necessary.
For example, when it is desired to obtain a powdery glass composition, the glass composition may be pulverized by a dry pulverization method or a wet pulverization method. In the case of the wet pulverization method, it is preferable to use water as a solvent. The crushing can be performed using a crusher such as a roll mill, a ball mill, or a jet mill. Further, the particle size (D 50 ) of the powdery glass composition can be adjusted by classifying as necessary after pulverization.
また、本発明のガラス組成物が組成の異なる複数種のガラス組成物の混合物である場合は、上記のようにして得られたガラス組成物を混合することにより得られる。この際の混合方法は特に限定されないが、例えばＶミキサー等を用いて１〜２時間混合する方法が挙げられる。また、本発明のガラス組成物が組成の異なる複数種のガラス粉末の混合物である場合は、複数種のガラス組成物を混合した後に粉砕して粉状にしてもよいが、複数種のガラス組成物をそれぞれ粉砕して粉状にした後に混合することが好ましい。 When the glass composition of the present invention is a mixture of a plurality of types of glass compositions having different compositions, it can be obtained by mixing the glass compositions obtained as described above. The mixing method at this time is not particularly limited, and examples thereof include a method of mixing for 1 to 2 hours using a V mixer or the like. When the glass composition of the present invention is a mixture of a plurality of types of glass powders having different compositions, the plurality of types of glass compositions may be mixed and then pulverized into a powder, but the plurality of types of glass compositions may be obtained. It is preferable to grind each of the substances into powder and then mix them.
本発明のガラス組成物は、半導体基板上への電極形成、例えば、太陽電池の電極形成に好適に用いられる。本発明のガラス組成物は特に、ファイヤースルーにより電極を形成する導電ペーストの材料として好適に用いられる。更には、Ａｌ電極を形成するための導電ペーストの材料として用いられた際に、特に効果を発揮する。後述の＜２．ガラス組成物の製造方法＞の欄において説明する方法により得られるガラス組成物についても同様である。 The glass composition of the present invention is suitably used for forming electrodes on a semiconductor substrate, for example, forming electrodes for a solar cell. The glass composition of the present invention is particularly preferably used as a material for a conductive paste that forms an electrode by fire-through. Further, it is particularly effective when used as a material for a conductive paste for forming an Al electrode. <2. The same applies to the glass composition obtained by the method described in the column of> Method for producing glass composition>.
＜２．ガラス組成物の製造方法＞
次に、本発明において提供されるガラス組成物の製造方法（以下「本発明の製造方法」ともいう）について説明する。
本発明の製造方法は、酸化物基準のモル％表記でＢ２Ｏ３を３５％以上６０％以下、Ｋ２Ｏを１％以上４０％以下、ＣａＯを３％以上３０％以下、ＢａＯを２％以上２５％以下、ＳｉＯ２を５％以上１０％以下含有し、実質的にＰｂＯとＣｕＯとを含まない第１のガラス組成物と、酸化物基準のモル％表記で、Ｂｉ２Ｏ３を５％以上６０％以下、Ｂ２Ｏ３を１５％以上８０％以下含有し、実質的にＰｂＯとＣｕＯとを含まない第２のガラス組成物とを混合する工程を含む。
なお、本発明の製造方法は、＜１．ガラス組成物＞の欄において説明した本発明のガラス組成物を製造する方法に限定されず、本発明のガラス組成物に包含されないガラス組成物を製造する方法も包含する。
<2. Manufacturing method of glass composition>
Next, a method for producing the glass composition provided in the present invention (hereinafter, also referred to as “the method for producing the present invention”) will be described.
In the production method of the present invention, B 2 O 3 is 35% or more and 60% or less, K 2 O is 1% or more and 40% or less, Ca O is 3% or more and 30% or less, and Ba O is 2 in mol% notation based on oxides. A first glass composition containing% or more and 25% or less, SiO 2 5% or more and 10% or less, and substantially free of PbO and CuO, and Bi 2 O 3 in terms of oxide-based mol%. 60% more than 5% or less, B 2 O 3 and containing 80% or less than 15% comprising the step of mixing the second glass composition is substantially free of the PbO and CuO.
The production method of the present invention is described in <1. The method is not limited to the method for producing the glass composition of the present invention described in the column of> Glass composition>, and also includes the method for producing a glass composition not included in the glass composition of the present invention.
上記第２のガラス組成物はＢｉ２Ｏ３を含むことから絶縁膜との反応性に優れるガラス組成物であり、主として絶縁膜の貫通に寄与する成分である。上記第１のガラス組成物は、主として絶縁膜貫通後の電極と半導体基板との反応の促進に寄与する成分である。これらのガラス組成物を混合する本発明の製造方法により得られるガラス組成物は、絶縁膜との反応性、及び、絶縁膜貫通後の電極と半導体基板との反応の促進効果の両方に優れる。したがって、本発明の製造方法により得られるガラス組成物を含む導電ペーストを用いると、絶縁膜貫通電極を容易に形成することができ、また、半導体基板との接触抵抗の低い電極を形成できる。 Since the second glass composition contains Bi 2 O 3 , it is a glass composition having excellent reactivity with the insulating film, and is a component that mainly contributes to the penetration of the insulating film. The first glass composition is a component that mainly contributes to the promotion of the reaction between the electrode and the semiconductor substrate after penetrating the insulating film. The glass composition obtained by the production method of the present invention in which these glass compositions are mixed is excellent in both the reactivity with the insulating film and the effect of promoting the reaction between the electrode and the semiconductor substrate after penetrating the insulating film. Therefore, by using the conductive paste containing the glass composition obtained by the production method of the present invention, the insulating film penetrating electrode can be easily formed, and the electrode having low contact resistance with the semiconductor substrate can be formed.
以下に、第１のガラス組成物に含有される成分について説明する。 The components contained in the first glass composition will be described below.
Ｂ２Ｏ３は先述のとおり、ガラス組成物の安定性及び軟化時の流動性の向上に寄与し、また、半導体基板との接合強度を向上させる成分である。当該効果を奏するために、第１のガラス組成物のＢ２Ｏ３の含有量は３５％以上、好ましくは３８％以上、より好ましくは４０％以上である。
一方、第１のガラス組成物のＢ２Ｏ３の含有量が６０％超であると、本実施形態のガラス組成物の耐候性が劣化する恐れがある。したがって、第１のガラス組成物のＢ２Ｏ３の含有量は６０％以下、好ましくは５８％以下、より好ましくは５５％以下である。
As described above, B 2 O 3 is a component that contributes to the improvement of the stability of the glass composition and the fluidity at the time of softening, and also improves the bonding strength with the semiconductor substrate. In order to exert the effect, the content of B 2 O 3 in the first glass composition is 35% or more, preferably 38% or more, more preferably 40% or more.
On the other hand, if the content of B 2 O 3 in the first glass composition exceeds 60%, the weather resistance of the glass composition of the present embodiment may deteriorate. Therefore, the content of B 2 O 3 in the first glass composition is 60% or less, preferably 58% or less, and more preferably 55% or less.
Ｋ２Ｏは先述のとおり、ガラス組成物の安定性及び軟化時の流動性の向上に寄与し、半導体基板との接合強度を向上させ、また、電極と半導体基板との間の接触抵抗を下げる成分である。当該効果を奏するために、第１のガラス組成物のＫ２Ｏの含有量は１％以上、好ましくは６％以上、より好ましくは１０％以上である。
一方、第１のガラス組成物のＫ２Ｏの含有量が４０％超であると、結晶化によりガラス組成物が得られない恐れがある。したがって、第１のガラス組成物のＫ２Ｏの含有量は４０％以下、好ましくは３５％以下、より好ましくは２５％以下である。
As described above, K 2 O contributes to the improvement of the stability of the glass composition and the fluidity at the time of softening, improves the bonding strength with the semiconductor substrate, and lowers the contact resistance between the electrode and the semiconductor substrate. It is an ingredient. To achieve the effect, the content of K 2 O of the first glass composition 1% or more, preferably 6% or more, more preferably 10% or more.
On the other hand, when the content of K 2 O of the first glass composition is 40 percent, there may not glass composition is obtained by crystallization. Thus, 40% K 2 O content of the first glass composition or less, preferably 35% or less, more preferably 25% or less.
ＣａＯは先述のとおり、電極と半導体基板との接触抵抗の低下に寄与する成分である。当該効果を奏するために、第１のガラス組成物のＣａＯの含有量は３％以上、好ましくは４％以上、より好ましくは５％以上である。
一方、第１のガラス組成物のＣａＯの含有量が３０％超であると、結晶化によりガラス組成物が得られない恐れがある。したがって、第１のガラス組成物のＣａＯの含有量は３０％以下、好ましくは２８％以下、より好ましくは２５％以下である。
As described above, CaO is a component that contributes to a decrease in contact resistance between the electrode and the semiconductor substrate. In order to exert the effect, the CaO content of the first glass composition is 3% or more, preferably 4% or more, and more preferably 5% or more.
On the other hand, if the CaO content of the first glass composition is more than 30%, the glass composition may not be obtained due to crystallization. Therefore, the CaO content of the first glass composition is 30% or less, preferably 28% or less, and more preferably 25% or less.
ＢａＯは先述のとおり、電極と半導体基板との接触抵抗の低下に寄与する成分である。当該効果を奏するために、第１のガラス組成物のＢａＯの含有量は２％以上、好ましくは３％以上である。
一方、第１のガラス組成物のＢａＯの含有量が２５％超であると、結晶化によりガラス組成物が得られない恐れがある。したがって、第１のガラス組成物のＢａＯの含有量は２５％以下、好ましくは２０％以下である。
As described above, BaO is a component that contributes to a decrease in contact resistance between the electrode and the semiconductor substrate. In order to exert the effect, the content of BaO in the first glass composition is 2% or more, preferably 3% or more.
On the other hand, if the BaO content of the first glass composition is more than 25%, the glass composition may not be obtained due to crystallization. Therefore, the BaO content of the first glass composition is 25% or less, preferably 20% or less.
ＳｉＯ２は先述のとおり、ガラス組成物の耐候性の向上及び安定性の向上に寄与する成分である。当該効果を奏するために、第１のガラス組成物のＳｉＯ２の含有量は５％以上、好ましくは６％以上である。
一方、第１のガラス組成物のＳｉＯ２の含有量が１０％超であると、ガラス転移点が高くなり、ガラス組成物が流動しにくくなる恐れがある。したがって、第１のガラス組成物のＳｉＯ２の含有量は１０％以下、好ましくは９％以下である。
As described above, SiO 2 is a component that contributes to the improvement of weather resistance and the improvement of stability of the glass composition. In order to achieve this effect, the content of SiO 2 in the first glass composition is 5% or more, preferably 6% or more.
On the other hand, if the content of SiO 2 in the first glass composition is more than 10%, the glass transition point becomes high and the glass composition may not flow easily. Therefore, the content of SiO 2 in the first glass composition is 10% or less, preferably 9% or less.
第１のガラス組成物は、さらにＳｒＯを含有してもよい。第１のガラス組成物にＳｒＯを含有させることにより、本実施形態のガラス組成物のファイヤースルー性がより一層向上する。第１のガラス組成物にＳｒＯを含有させる場合の含有量は、好ましくは３％以上である。一方、第１のガラス組成物がＳｒＯを過剰に含むと、ガラス化しない恐れがある。したがって、第１のガラス組成物にＳｒＯを含有させる場合の含有量は、好ましくは１５％以下、より好ましくは１０％以下である。 The first glass composition may further contain SrO. By including SrO in the first glass composition, the fire-through property of the glass composition of the present embodiment is further improved. When SrO is contained in the first glass composition, the content is preferably 3% or more. On the other hand, if the first glass composition contains an excess of SrO, it may not be vitrified. Therefore, when SrO is contained in the first glass composition, the content is preferably 15% or less, more preferably 10% or less.
次に、第２のガラス組成物に含有される成分について説明する。 Next, the components contained in the second glass composition will be described.
Ｂｉ２Ｏ３は先述のとおり、ガラス組成物と絶縁膜との反応性を向上させる成分である当該効果を奏するために、第２のガラス組成物のＢｉ２Ｏ３の含有量は５％以上、好ましくは１０％以上、より好ましくは２０％以上である。
一方、第２のガラス組成物のＢｉ２Ｏ３の含有量が６０％超であると、結晶化によりガラス組成物が得られない恐れがある。したがって、第２のガラス組成物のＢｉ２Ｏ３の含有量は６０％以下、好ましくは５５％以下である。
As described above, Bi 2 O 3 is a component that improves the reactivity between the glass composition and the insulating film. In order to exert the effect, the content of Bi 2 O 3 in the second glass composition is 5% or more. It is preferably 10% or more, more preferably 20% or more.
On the other hand, if the content of Bi 2 O 3 in the second glass composition is more than 60%, the glass composition may not be obtained due to crystallization. Therefore, the content of Bi 2 O 3 in the second glass composition is 60% or less, preferably 55% or less.
Ｂ２Ｏ３は先述のとおり、ガラス組成物の安定性及び軟化時の流動性の向上に寄与し、また、半導体基板との接合強度を向上させる成分である。当該効果を奏するために、第２のガラス組成物のＢ２Ｏ３の含有量は１５％以上、好ましくは２０％以上、より好ましくは３０％以上である。
一方、第２のガラス組成物のＢ２Ｏ３の含有量が８０％超であると、本実施形態のガラス組成物の耐候性が劣化する恐れがある。したがって、第１のガラス組成物のＢ２Ｏ３の含有量は８０％以下、好ましくは７０％以下である。
As described above, B 2 O 3 is a component that contributes to the improvement of the stability of the glass composition and the fluidity at the time of softening, and also improves the bonding strength with the semiconductor substrate. In order to exert the effect, the content of B 2 O 3 in the second glass composition is 15% or more, preferably 20% or more, more preferably 30% or more.
On the other hand, if the content of B 2 O 3 in the second glass composition exceeds 80%, the weather resistance of the glass composition of the present embodiment may deteriorate. Therefore, the content of B 2 O 3 in the first glass composition is 80% or less, preferably 70% or less.
また、第１のガラス組成物および第２のガラス組成物は、上記成分以外にも例えば、ＺｎＯ、Ｐ２Ｏ５、Ａｓ２Ｏ５、ＭｇＯ、Ｌｉ２Ｏ、Ｎａ２Ｏ、ＺｒＯ２、Ａｌ２Ｏ３、Ｆｅ２Ｏ３、Ｓｂ２Ｏ３、Ｓｂ２Ｏ５、ＳｎＯ２、ＭｏＯ３、ＷＯ３、ＭｎＯ、ＭｎＯ２、ＣｅＯ２、ＴｉＯ２等の通常ガラスに用いられる各種酸化物成分を含有してもよい。これらの酸化物成分は目的に応じて、１種を単独で、または２種以上を組み合せて用いることができる。これらの成分の含有量は、本発明の方法により得られるガラス組成物において５％以下となるようにすることが好ましい。 In addition to the above components, the first glass composition and the second glass composition also contain, for example, ZnO, P 2 O 5 , As 2 O 5 , MgO, Li 2 O, Na 2 O, ZrO 2 , Al. Various oxide components used in ordinary glass such as 2 O 3 , Fe 2 O 3 , Sb 2 O 3 , Sb 2 O 5 , SnO 2 , MoO 3 , WO 3 , MnO, MnO 2 , CeO 2 , and TiO 2 It may be contained. These oxide components may be used alone or in combination of two or more, depending on the purpose. The content of these components is preferably 5% or less in the glass composition obtained by the method of the present invention.
また、先述のとおりＰｂＯは環境負荷物質であり、したがって、第１のガラス組成物および第２のガラス組成物は、いずれもＰｂＯを実質的に含有しない。なお、第１のガラス組成物および第２のガラス組成物にはＰｂＯが不純物として含まれる場合がある。第１のガラス組成物および第２のガラス組成物のＰｂＯの含有量は、いずれも好ましくは０．１％以下である。 Further, as described above, PbO is an environmentally hazardous substance, and therefore, neither the first glass composition nor the second glass composition substantially contains PbO. The first glass composition and the second glass composition may contain PbO as an impurity. The contents of PbO in both the first glass composition and the second glass composition are preferably 0.1% or less.
また、先述のとおりＣｕＯは半導体基板中を拡散して半導体基板の特性を劣化させやすい成分であり、したがって、第１のガラス組成物および第２のガラス組成物は、いずれもＣｕＯを実質的に含有しない。なお、第１のガラス組成物および第２のガラス組成物にはＣｕＯが不純物として含まれる場合がある。第１のガラス組成物および第２のガラス組成物のＣｕＯの含有量は、いずれも好ましくは０．１％以下である。 Further, as described above, CuO is a component that easily diffuses in the semiconductor substrate and deteriorates the characteristics of the semiconductor substrate. Therefore, both the first glass composition and the second glass composition substantially contain CuO. Does not contain. In addition, CuO may be contained as an impurity in the first glass composition and the second glass composition. The CuO content of both the first glass composition and the second glass composition is preferably 0.1% or less.
第１のガラス組成物及び第２のガラス組成物の形状、Ｄ５０、結晶化度、製造方法については、＜１．ガラス組成物＞の欄において説明した本発明のガラス組成物と同様である。 Shape of the first glass composition and a second glass composition, D 50, the degree of crystallinity, the manufacturing method, <1. It is the same as the glass composition of the present invention described in the column of “Glass composition>”.
本発明の製造方法の第１のガラス組成物と第２のガラス組成物とを混合する工程（以下単に「本発明の製造方法の混合工程」ともいう）における混合方法は第１及び第２のガラス組成物が均一に混合される方法であれば特に限定されない。例えば、Ｖミキサー等を用いて１〜２時間混合する方法が挙げられる。 The mixing method in the step of mixing the first glass composition and the second glass composition of the manufacturing method of the present invention (hereinafter, also simply referred to as "mixing step of the manufacturing method of the present invention") is the first and second. The method is not particularly limited as long as the glass composition is uniformly mixed. For example, a method of mixing for 1 to 2 hours using a V mixer or the like can be mentioned.
本発明の製造方法の混合工程における第１のガラス組成物：第２のガラス組成物の混合割合は特に限定されないが、先述の第１及び第２のガラス組成物の効果を充分に発揮するためには、質量比で８０：２０〜４０：６０が好ましく、７５：２５〜４５：５５がより好ましい。また、本発明の製造方法により得られるガラス組成物の平均組成が＜１．ガラス組成物＞の欄において説明した本発明のガラス組成物の組成と同様になるような混合割合が特に好ましい。
また、本発明の製造方法の混合工程では、本発明の効果を奏する範囲で、第１及び第２のガラス組成物に加え更にその他のガラス組成物を混合させてもよい。
The mixing ratio of the first glass composition: the second glass composition in the mixing step of the production method of the present invention is not particularly limited, but in order to fully exert the effects of the first and second glass compositions described above. The mass ratio is preferably 80:20 to 40:60, more preferably 75:25 to 45:55. Further, the average composition of the glass composition obtained by the production method of the present invention is <1. A mixing ratio that is similar to the composition of the glass composition of the present invention described in the column of> Glass composition> is particularly preferable.
Further, in the mixing step of the production method of the present invention, other glass compositions may be further mixed in addition to the first and second glass compositions as long as the effects of the present invention are exhibited.
＜３．導電ペースト＞
次に、本発明において提供される導電ペーストについて説明する。
本発明の導電ペーストは、＜１．ガラス組成物＞の欄において説明したガラス組成物の粉末（以下、「本発明のガラス粉末」ともいう）と、導電性金属粉末と、有機ビヒクルとを含有する。
すなわち、本発明の導電ペーストは、酸化物基準のモル％表記で、Ｂｉ２Ｏ３を３％以上１９％以下、Ｂ２Ｏ３を２０％以上７０％以下、ＳｉＯ２を１％以上３０％以下、Ｋ２Ｏを３％以上２０％以下、ＣａＯを３％以上２０％以下、ＢａＯを１％以上２０％以下含有し、実質的にＰｂＯとＣｕＯとを含まないガラスの粉末と、導電性金属粉末と、有機ビヒクルとを含有する導電ペーストである。
<3. Conductive paste>
Next, the conductive paste provided in the present invention will be described.
The conductive paste of the present invention is <1. It contains the powder of the glass composition described in the column of> Glass composition> (hereinafter, also referred to as "glass powder of the present invention"), the conductive metal powder, and the organic vehicle.
That is, the conductive paste of the present invention contains Bi 2 O 3 of 3% or more and 19% or less, B 2 O 3 of 20% or more and 70% or less, and SiO 2 of 1% or more and 30% in mol% notation based on oxides. hereinafter, the K 2 O 3% to 20% or less, the CaO 3% to 20% or less, contain 1% to 20% of BaO, substantially a powder of glass which does not contain the PbO and CuO, conductive A conductive paste containing a metal powder and an organic vehicle.
本発明の導電ペーストに含有される導電性金属粉末として、半導体基板上に形成される電極に通常用いられる金属の粉末が特に制限なく用いられる。導電性金属粉末として、具体的には、Ａｌ、Ａｇ、Ｃｕ、Ａｕ、Ｐｄ、Ｐｔ等の粉末が挙げられ、これらのうちでも、Ａｌ粉末が好ましい。Ａｌ粉末を導電性金属粉末として用いると、導電ペーストに含まれる本発明のガラス粉末の絶縁膜を貫通する効果、及びＳｉ基板との反応性を高める効果が特に特に顕著に発揮される。
導電性金属粉末のＤ５０は、凝集の抑制及び分散性の向上のために１〜１０μｍが好ましい。
As the conductive metal powder contained in the conductive paste of the present invention, a metal powder usually used for an electrode formed on a semiconductor substrate is used without particular limitation. Specific examples of the conductive metal powder include powders of Al, Ag, Cu, Au, Pd, Pt and the like, and among these, Al powder is preferable. When Al powder is used as the conductive metal powder, the effect of penetrating the insulating film of the glass powder of the present invention contained in the conductive paste and the effect of enhancing the reactivity with the Si substrate are particularly remarkable.
The D 50 of the conductive metal powder is preferably 1 to 10 μm in order to suppress aggregation and improve dispersibility.
本発明の導電ペーストのガラス粉末の含有量は、特に限定されないが、導電性金属粉末１００質量部に対して０．１質量部以上、好ましくは０．５質量部以上とすることにより、特に良好なファイヤースルー性が得られる。
一方、ガラス粉末の含有量を導電性金属粉末１００質量部に対して１５質量部以下、より好ましくは１０質量部以下とすることにより、得られる電極の電気抵抗が小さくなる。
ガラス粉末のＤ５０は、凝集の抑制及び分散性の向上のために０．５μｍ以上が好ましく、１．０μｍ以上がより好ましく、また、１０μｍ以下が好ましく、５．０μｍ以下がより好ましい。
The content of the glass powder of the conductive paste of the present invention is not particularly limited, but is particularly good when it is 0.1 parts by mass or more, preferably 0.5 parts by mass or more with respect to 100 parts by mass of the conductive metal powder. Fire-through property can be obtained.
On the other hand, when the content of the glass powder is 15 parts by mass or less, more preferably 10 parts by mass or less with respect to 100 parts by mass of the conductive metal powder, the electric resistance of the obtained electrode is reduced.
The D 50 of the glass powder is preferably 0.5 μm or more, more preferably 1.0 μm or more, preferably 10 μm or less, and more preferably 5.0 μm or less in order to suppress aggregation and improve dispersibility.
本発明の導電ペーストに含有される有機ビヒクルとしては、有機樹脂バインダーを溶媒に溶解して得られる有機樹脂バインダー溶液を用いることができる。 As the organic vehicle contained in the conductive paste of the present invention, an organic resin binder solution obtained by dissolving an organic resin binder in a solvent can be used.
有機樹脂バインダーとしては、例えばメチルセルロース、エチルセルロース、カルボキシメチルセルロース、オキシエチルセルロース、ベンジルセルロース、プロピルセルロース、ニトロセルロース等のセルロース系樹脂、メチルメタクリレート、エチルメタクリレート、ブチルメタクリレート、２−ヒドロキシエチルメタクリレート、ブチルアクリレート、２−ヒドロキシエチルアクリレート等のアクリル系モノマーの１種以上を重合して得られるアクリル系樹脂等の有機樹脂が用いられる。 Examples of the organic resin binder include cellulosic resins such as methyl cellulose, ethyl cellulose, carboxymethyl cellulose, oxyethyl cellulose, benzyl cellulose, propyl cellulose and nitro cellulose, methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-hydroxyethyl methacrylate, butyl acrylate, 2 -An organic resin such as an acrylic resin obtained by polymerizing one or more of acrylic monomers such as hydroxyethyl acrylate is used.
溶媒としては、セルロース系樹脂の場合はターピネオール、ブチルジグリコールアセテート、エチルジグリコールアセテート、プロピレングリコールジアセテート等の溶媒が、アクリル系樹脂の場合はメチルエチルケトン、ターピネオール、ブチルジグリコールアセテート、エチルジグリコールアセテート、プロピレングリコールジアセテート等の溶媒が好ましく用いられる。 Solvents such as tarpineol, butyl diglycol acetate, ethyl diglycol acetate, and propylene glycol diacetate in the case of cellulose-based resins, and methyl ethyl ketone, tarpineol, butyl diglycol acetate, ethyl diglycol acetate in the case of acrylic resins , Propylene glycol diacetate and other solvents are preferably used.
有機ビヒクルにおける有機樹脂バインダーと溶媒の割合は、特に制限されないが、得られる有機樹脂バインダー溶液が導電ペーストの粘度を調整できる粘度となるように選択される。具体的には、有機樹脂バインダー：溶媒の質量比が、３：９７〜１５：８５程度であることが好ましい。 The ratio of the organic resin binder to the solvent in the organic vehicle is not particularly limited, but is selected so that the obtained organic resin binder solution has a viscosity that can adjust the viscosity of the conductive paste. Specifically, the mass ratio of the organic resin binder: solvent is preferably about 3:97 to 15:85.
本発明の導電ペーストにおける有機ビヒクルの含有量は、特に限定されないが、導電ペースト全量に対して５質量％以上とすると良好な塗布性が得られるため好ましい。
一方、本発明の導電ペーストにおける有機ビヒクルの含有量は、導電ペースト全量に対して３０質量％以下とすると導電ペーストの固形分の含有割合が好適な範囲となり、十分な塗布膜厚が得られやすいため好ましい。
The content of the organic vehicle in the conductive paste of the present invention is not particularly limited, but it is preferable that the content is 5% by mass or more based on the total amount of the conductive paste because good coatability can be obtained.
On the other hand, when the content of the organic vehicle in the conductive paste of the present invention is 30% by mass or less with respect to the total amount of the conductive paste, the content ratio of the solid content of the conductive paste is in a suitable range, and a sufficient coating film thickness can be easily obtained. Therefore, it is preferable.
本発明の導電ペーストには、本発明のガラス粉末、導電性金属粉末、および有機ビヒクルに加え、必要に応じて、かつ、本発明の目的に反しない限度において公知の添加剤を配合することができる。 In addition to the glass powder, the conductive metal powder, and the organic vehicle of the present invention, the conductive paste of the present invention may contain known additives as necessary and to the extent not contrary to the object of the present invention. it can.
添加剤としては、例えば、各種無機酸化物が挙げられる。無機酸化物として具体的には、Ｂ２Ｏ３、ＳｉＯ２、Ａｌ２Ｏ３、ＴｉＯ２、ＭｇＯ、ＺｒＯ２、Ｓｂ２Ｏ３、およびこれらの複合酸化物等が挙げられる。これらの無機酸化物は、導電ペーストの焼成に際し、導電性金属粉末の焼結を和らげる効果があり、それにより、焼成後の電極表面のブリスター発生を抑制する作用を有する。これらの無機酸化物の大きさは特に限定されるものではないが、例えば、Ｄ５０が１０μｍ以下であることが好ましい。 Examples of the additive include various inorganic oxides. Specific examples of the inorganic oxide include B 2 O 3 , SiO 2 , Al 2 O 3 , TiO 2 , MgO, ZrO 2 , Sb 2 O 3 , and composite oxides thereof. These inorganic oxides have the effect of softening the sintering of the conductive metal powder when the conductive paste is fired, and thereby have the effect of suppressing the generation of blister on the electrode surface after firing. The size of these inorganic oxides is not particularly limited, but for example, D 50 is preferably 10 μm or less.
導電ペーストにおける、無機酸化物の含有量は目的に応じて適宜に設定されるものであり特に限定されないが、ガラス粉末１００質量部に対して１０質量部以下、好ましくは７質量部以下とすると、電極形成時に好適な流動性が得られやすくなり、電極と半導体基板との接着強度が高くなりやすい。
一方、導電ペーストにおける、無機酸化物の含有量をガラス粉末１００質量部に対して３質量部以上、好ましくは５質量部以上とすると、無機酸化物添加による効果（電極と半導体基板との電気抵抗抑制）を得られやすい。
The content of the inorganic oxide in the conductive paste is appropriately set according to the purpose and is not particularly limited, but is 10 parts by mass or less, preferably 7 parts by mass or less with respect to 100 parts by mass of the glass powder. It is easy to obtain suitable fluidity when forming the electrode, and the adhesive strength between the electrode and the semiconductor substrate is likely to be high.
On the other hand, when the content of the inorganic oxide in the conductive paste is 3 parts by mass or more, preferably 5 parts by mass or more with respect to 100 parts by mass of the glass powder, the effect of adding the inorganic oxide (electrical resistance between the electrode and the semiconductor substrate). Suppression) is easy to obtain.
導電ペーストには、消泡剤や分散剤のように導電ペーストの分野において公知の添加物を加えてもよい。なお、上記有機ビヒクルおよびこれらの添加物は、通常、電極形成の過程で消失する成分である。導電ペーストの調製には、撹拌翼を備えた回転式の混合機や擂潰機、ロールミル、ボールミル等を用いた公知の方法を適用することができる。 Additives known in the field of conductive paste, such as antifoaming agents and dispersants, may be added to the conductive paste. The organic vehicle and these additives are components that usually disappear in the process of electrode formation. A known method using a rotary mixer equipped with a stirring blade, a grinder, a roll mill, a ball mill, or the like can be applied to the preparation of the conductive paste.
本発明の導電ペーストは、半導体基板上への焼成による電極形成、特には、半導体基板上に設けられた絶縁膜上に導電ペーストを部分的に塗布してファイヤースルーにより行われる電極形成に好適に用いられる。本発明の導電ペーストを用いれば、焼成時に、導電ペーストが塗布された部分において、該導電ペーストが含有するガラス中の酸素が導電性金属粉末に拡散するのを抑制しながら、ガラスが絶縁膜材料と反応し絶縁膜を溶融させることで、絶縁膜を貫通し半導体基板に十分に接触する電極が得られる。
本発明の導電ペーストを用いて形成した電極、具体的には、半導体基板上に焼付けられた電極を具備する製品としては、太陽電池、ダイオード素子、トランジスタ素子、サイリスタ等が挙げられる。本発明の導電ペーストは、太陽電池の製造において、絶縁膜付き半導体基板上にファイヤースルーにより絶縁膜を部分的に貫通して半導体基板に接触する電極を形成するのに特に好適である。例えば、ｐ型Ｓｉ基板を用いたＰＥＲＣ太陽電池の裏面電極、ｎ型Ｓｉ基板を用いたＰＥＲＴ（Passivated Emitter, Rear Totally diffused）太陽電池の裏面電極、ｎ型Ｓｉ基板またはｐ型Ｓｉ基板を用いた両面受光太陽電池の、ｐ層またはｐ＋層側に設けられた電極、バックコンタクト型太陽電池の一方の電極の形成に好適である。
The conductive paste of the present invention is suitable for electrode formation by firing on a semiconductor substrate, particularly for electrode formation performed by fire-through by partially applying the conductive paste on an insulating film provided on the semiconductor substrate. Used. When the conductive paste of the present invention is used, the glass becomes an insulating film material while suppressing the oxygen in the glass contained in the conductive paste from diffusing into the conductive metal powder at the portion where the conductive paste is applied during firing. By reacting with and melting the insulating film, an electrode that penetrates the insulating film and sufficiently contacts the semiconductor substrate can be obtained.
Examples of products including electrodes formed by using the conductive paste of the present invention, specifically, electrodes baked on a semiconductor substrate, include solar cells, diode elements, transistor elements, thyristors, and the like. The conductive paste of the present invention is particularly suitable for forming an electrode on a semiconductor substrate with an insulating film that partially penetrates the insulating film by fire-through and comes into contact with the semiconductor substrate in the manufacture of a solar cell. For example, a back electrode of a PERC solar cell using a p-type Si substrate, a back electrode of a PERT (Passivated Emitter, Rear Totally diffused) solar cell using an n-type Si substrate, an n-type Si substrate or a p-type Si substrate were used. It is suitable for forming an electrode provided on the p-layer or p + layer side of a double-sided light-receiving solar cell, or one electrode of a back-contact type solar cell.
絶縁膜上への導電ペーストの塗布および焼成は、従来のファイヤースルーにより行われる電極形成における塗布、焼成と同様の方法により行うことができる。塗布方法としては、スクリーン印刷、ディスペンス等が挙げられる。焼成温度は、含有する導電性金属粉末の種類、ガラス粉末の種類等によるが、例えば約６００〜１０００℃である。焼成時間は、貫通させる絶縁膜の厚さ、半導体基板等により適宜調整される。また、導電ペーストの塗布と焼成の間に、１００〜２００℃程度での乾燥処理を施してもよい。 The coating and firing of the conductive paste on the insulating film can be performed by the same method as the coating and firing in the electrode formation performed by the conventional fire-through. Examples of the coating method include screen printing and dispensing. The firing temperature depends on the type of conductive metal powder contained, the type of glass powder, and the like, but is, for example, about 600 to 1000 ° C. The firing time is appropriately adjusted depending on the thickness of the insulating film to be penetrated, the semiconductor substrate, and the like. Further, a drying treatment at about 100 to 200 ° C. may be performed between the application of the conductive paste and the firing.
＜４．太陽電池＞
次に、本発明において提供される太陽電池について説明する。
本発明の太陽電池は、＜３．導電ペースト＞の欄において説明した導電ペーストにより形成された電極を具備する。
本発明の太陽電池においては、電極の少なくとも１つが、本発明の導電ペーストを用いて、ファイヤースルーにより、絶縁膜を部分的に貫通して半導体基板に接触する形に設けられた電極であることが好ましい。
<4. Solar cell ＞
Next, the solar cell provided in the present invention will be described.
The solar cell of the present invention is <3. It includes an electrode formed of the conductive paste described in the column of Conductive paste>.
In the solar cell of the present invention, at least one of the electrodes is an electrode provided so as to partially penetrate the insulating film and come into contact with the semiconductor substrate by fire-through using the conductive paste of the present invention. Is preferable.
本発明の太陽電池の具体的な実施態様として、例えば太陽光受光面を有するシリコン基板と、シリコン基板の太陽光受光面に設けられた第１の絶縁膜と、シリコン基板の太陽光受光面とは反対側の面に設けられた第２の絶縁膜と、第１の絶縁膜の一部を貫通して前記シリコン基板に接触する第１の電極と、前記第２の絶縁膜の一部を貫通して前記シリコン基板に接触する第２の電極とを備える太陽電池であって、第１の電極は、Ａｌ、Ａｇ、Ｃｕ、Ａｕ、ＰｄおよびＰｔからなる群から選択される少なくとも１種を含む第１の金属と、第１のガラスとを含み、第２の電極は、Ａｌ、Ａｇ、Ｃｕ、Ａｕ、ＰｄおよびＰｔからなる群から選択される少なくとも１種を含む第２の金属と、酸化物基準のモル％表記で、Ｂｉ２Ｏ３を３％以上１９％以下、Ｂ２Ｏ３を２０％以上７０％以下、ＳｉＯ２を１％以上３０％以下、Ｋ２Ｏを３％以上２０％以下、ＣａＯを３％以上２０％以下、ＢａＯを１％以上２０％以下含有し、実質的にＰｂＯとＣｕＯとを含まない第２のガラスを含む太陽電池が挙げられる。 As a specific embodiment of the solar cell of the present invention, for example, a silicon substrate having a sunlight receiving surface, a first insulating film provided on the sunlight receiving surface of the silicon substrate, and a sunlight receiving surface of the silicon substrate. A second insulating film provided on the opposite surface, a first electrode that penetrates a part of the first insulating film and comes into contact with the silicon substrate, and a part of the second insulating film. A solar cell including a second electrode that penetrates and contacts the silicon substrate, wherein the first electrode is at least one selected from the group consisting of Al, Ag, Cu, Au, Pd, and Pt. A second metal comprising a first metal containing and a first glass, and a second electrode comprising at least one selected from the group consisting of Al, Ag, Cu, Au, Pd and Pt. Bi 2 O 3 is 3% or more and 19% or less, B 2 O 3 is 20% or more and 70% or less, SiO 2 is 1% or more and 30% or less, and K 2 O is 3% or more in mol% notation based on oxides. Examples thereof include a solar cell containing a second glass containing 20% or less, CaO of 3% or more and 20% or less, BaO of 1% or more and 20% or less, and substantially free of PbO and CuO.
太陽電池が有する絶縁膜を貫通する電極としては、例えば、ｐｎ接合型の半導体基板を用いた太陽電池の受光面に設けられる電極であって、反射防止膜である絶縁膜を部分的に貫通して半導体基板に接触するように設けられた電極が挙げられる。反射防止膜である絶縁膜を構成する絶縁材料としては窒化珪素、二酸化チタン、二酸化珪素、酸化アルミニウム等が挙げられる。この場合、受光面は半導体基板の片面であっても両面であってもよく、半導体基板はｎ型、ｐ型のいずれであってもよい。このような太陽電池の受光面に設けられる電極は、本発明の導電ペーストを用いてファイヤースルーにより形成できる。 The electrode that penetrates the insulating film of the solar cell is, for example, an electrode provided on the light receiving surface of the solar cell using a pn junction type semiconductor substrate, and partially penetrates the insulating film that is an antireflection film. Examples thereof include electrodes provided so as to come into contact with the semiconductor substrate. Examples of the insulating material constituting the insulating film which is an antireflection film include silicon nitride, titanium dioxide, silicon dioxide, and aluminum oxide. In this case, the light receiving surface may be one side or both sides of the semiconductor substrate, and the semiconductor substrate may be either n-type or p-type. The electrode provided on the light receiving surface of such a solar cell can be formed by fire-through using the conductive paste of the present invention.
以下、本発明の導電ペーストで形成された電極を備えるｐ型Ｓｉ基板両面受光型の太陽電池を例に説明する。図１は、本発明の導電ペーストを用いて電極形成されたｐ型Ｓｉ基板両面受光型太陽電池の一例の断面を模式的に示した図である。 Hereinafter, a p-type Si substrate double-sided light receiving type solar cell including an electrode formed of the conductive paste of the present invention will be described as an example. FIG. 1 is a diagram schematically showing a cross section of an example of a p-type Si substrate double-sided light-receiving solar cell whose electrodes are formed by using the conductive paste of the present invention.
図１に示す太陽電池１０は、ｐ型Ｓｉ基板１と、その上面に設けられた絶縁膜２Ａ、下面に設けられた絶縁膜２Ｂを有し、絶縁膜２Ｂの一部を貫通してｐ型Ｓｉ基板に接触するＡｌ電極４、および絶縁膜２Ａの一部を貫通してｐ型Ｓｉ基板１に接触するＡｇ電極３を有する。ｐ型Ｓｉ基板１の上面は、例えば、ウエットエッチング法を用いて形成される、光反射率を低減させるような凹凸構造を有する。なお、図面の上下は、必ずしも使用時における上下を示すものではない。なお、必要に応じて、ｐ型Ｓｉ基板の両表面が凹凸構造を有してもよい。 The solar cell 10 shown in FIG. 1 has a p-type Si substrate 1, an insulating film 2A provided on the upper surface thereof, and an insulating film 2B provided on the lower surface thereof, and penetrates a part of the insulating film 2B to form a p-type. It has an Al electrode 4 that contacts the Si substrate and an Ag electrode 3 that penetrates a part of the insulating film 2A and contacts the p-type Si substrate 1. The upper surface of the p-type Si substrate 1 has a concavo-convex structure formed by, for example, a wet etching method, which reduces the light reflectance. The top and bottom of the drawing do not necessarily indicate the top and bottom during use. If necessary, both surfaces of the p-type Si substrate may have an uneven structure.
ｐ型Ｓｉ基板１は、上から順にｎ＋層１ａ、ｐ層１ｂで構成され、Ａｌ電極４はｐ層１ｂに、Ａｇ電極３はｎ＋層１ａに接触している。ここで、ｎ＋層１ａは、上記凹凸構造が形成された表面に、例えば、Ｐ、Ｓｂ、Ａｓ等をドープすることで形成され得る。 The p-type Si substrate 1 is composed of n + layer 1a and p layer 1b in this order from the top, the Al electrode 4 is in contact with the p layer 1b, and the Ag electrode 3 is in contact with n + layer 1a. Here, the n + layer 1a can be formed by doping the surface on which the uneven structure is formed, for example, with P, Sb, As, or the like.
Ａｌ電極４およびＡｇ電極３は、ガラス粉末とＡｌ粉末を含有するＡｌ電極形成用導電ペースト、ガラス粉末とＡｇ粉末を含有するＡｇ電極形成用導電ペーストを、それぞれ用いて次のようにして形成される。すなわち、ｐ型Ｓｉ基板１の両面に設けられた絶縁膜２Ｂ、絶縁膜２Ａは、Ａｌ電極４、Ａｇ電極３の形成前は全面に隙間なく存在し、Ａｌ電極４およびＡｇ電極３を形成するための上記導電ペーストがそれぞれ塗布された部分のみが導電ペーストの焼成時に溶融することで、絶縁膜２Ｂ、絶縁膜２Ａをそれぞれ貫通しｐ型Ｓｉ基板１に接触するＡｌ電極４およびＡｇ電極３が形成される。 The Al electrode 4 and the Ag electrode 3 are formed as follows by using an Al electrode forming conductive paste containing glass powder and Al powder and an Ag electrode forming conductive paste containing glass powder and Ag powder, respectively. To. That is, the insulating films 2B and 2A provided on both sides of the p-type Si substrate 1 exist on the entire surface without gaps before the formation of the Al electrode 4 and the Ag electrode 3, forming the Al electrode 4 and the Ag electrode 3. The Al electrode 4 and the Ag electrode 3 that penetrate the insulating film 2B and the insulating film 2A and come into contact with the p-type Si substrate 1 are formed by melting only the portion to which the above conductive paste is applied at the time of firing the conductive paste. It is formed.
なお、Ａｌ電極４は、絶縁膜２Ｂを貫通した後、ｐ型Ｓｉ基板１のｐ層１ｂに到達後、Ａｌ電極からＡｌがｐ層１ｂ内に拡散することでＡｌ電極直上にＡｌ−Ｓｉ合金層５を形成する。さらにＡｌ−Ｓｉ合金層５の直上にはｐ＋層としてＢＳＦ（Back Surface Field）層６が形成される。 The Al electrode 4 penetrates the insulating film 2B, reaches the p layer 1b of the p-type Si substrate 1, and then diffuses Al from the Al electrode into the p layer 1b to form an Al—Si alloy directly above the Al electrode. Form layer 5. Further, a BSF (Back Surface Field) layer 6 is formed as a p + layer directly above the Al—Si alloy layer 5.
当該太陽電池１０においてはＡｇ電極３及びＡｌ電極４のいずれかが本発明の導電ペーストを用いて形成されたものであればよいが、特にＡｌ電極が本発明の導電ペーストを用いて形成されたものであることが好ましい。 In the solar cell 10, any of the Ag electrode 3 and the Al electrode 4 may be formed by using the conductive paste of the present invention, and in particular, the Al electrode is formed by using the conductive paste of the present invention. It is preferable that the material is one.
なお、太陽電池が有する絶縁膜２Ａおよび絶縁膜２Ｂは、反射防止膜であり、該膜を構成する絶縁材料としては、上記に挙げた絶縁材料が使用可能である。反射防止膜は、単層膜であってもよく、多層膜であってもよい。本発明の導電ペーストは、特に窒化珪素を含む層と酸化アルミニウムを含む層を有する絶縁膜に対して高い貫通性を有する。 The insulating film 2A and the insulating film 2B of the solar cell are antireflection films, and the insulating materials mentioned above can be used as the insulating materials constituting the films. The antireflection film may be a single-layer film or a multilayer film. The conductive paste of the present invention has high penetrability especially for an insulating film having a layer containing silicon nitride and a layer containing aluminum oxide.
本発明の太陽電池は、本発明のガラスの粉末を含有する電極形成時に容易に絶縁膜を貫通し半導体基板との接触が確保された電極を形成し得る導電ペーストを用いて電極が形成されていることで、信頼性と生産性に優れる太陽電池である。 In the solar cell of the present invention, the electrode is formed by using a conductive paste that can easily penetrate the insulating film and form an electrode in which contact with the semiconductor substrate is ensured when forming the electrode containing the glass powder of the present invention. Therefore, it is a solar cell with excellent reliability and productivity.
以下、本発明について実施例を参照してさらに詳細に説明するが、本発明は実施例に限定されない。例１〜９は第１のガラス組成物の調製例、例１０〜１３は比較例用のガラス組成物の調製例である。例２１〜２３は第２のガラス組成物の調製例、例２４は比較例用のガラスである。例３１〜４１、５２はガラス組成物の実施例、例４２〜４６、５１、５３はガラス組成物の比較例である。 Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to Examples. Examples 1 to 9 are preparation examples of the first glass composition, and Examples 10 to 13 are preparation examples of the glass composition for comparative examples. Examples 21 to 23 are preparation examples of the second glass composition, and Example 24 is a glass for comparative example. Examples 31 to 41 and 52 are examples of glass compositions, and Examples 42 to 46, 51 and 53 are comparative examples of glass compositions.
［例１〜１３、例２１〜２４］
実施例および比較例のガラス組成物の製造に使用する第１のガラス組成物、比較例用のガラス組成物、第２のガラス組成物として、表１〜３に示す組成、特性を有するガラス粉末を製造した。すなわち、表１〜３に示す組成となるように原料粉末を配合、混合し、１０００〜１３００℃の電気炉中で白金ルツボを用いて３０分〜１時間溶融し、薄板状ガラスを成形した後、この薄板状ガラスをボールミルでＤ５０が所定の範囲（０．５〜１０μｍ）となるように乾式粉砕し、１５０メッシュの篩にて粗粒を除去した。
[Examples 1 to 13, Examples 21 to 24]
As the first glass composition used for producing the glass compositions of Examples and Comparative Examples, the glass composition for Comparative Examples, and the second glass composition, glass powders having the compositions and properties shown in Tables 1 to 3 are obtained. Manufactured. That is, the raw material powders are blended and mixed so as to have the compositions shown in Tables 1 to 3, and melted in an electric furnace at 1000 to 1300 ° C. for 30 minutes to 1 hour using a platinum crucible to form a thin plate glass. The thin plate-shaped glass was dry-ground with a ball mill so that D 50 was within a predetermined range (0.5 to 10 μm), and coarse particles were removed with a 150 mesh sieve.
例１〜１３のガラス組成物（ガラス粉末）については、上記所定の範囲内でＤ５０をより小さくさせるために、上記乾式粉砕後、粗粒を除去するために気流分級によって得られたガラス粉末を用いた。 For the glass compositions (glass powders) of Examples 1 to 13, the glass powder obtained by airflow classification to remove coarse particles after the dry pulverization in order to make D 50 smaller within the predetermined range. Was used.
例２１〜２４のガラス組成物（ガラス粉末）については、上記所定の範囲内でＤ５０をより小さくさせるために、上記乾式粉砕後、粗粒を除去したガラス粉末をさらにボールミルで水を用いて湿式粉砕して得られたガラス粉末を用いた。この湿式粉砕の際に所定のＤ５０を得るために直径５ｍｍのアルミナ製のボールを用いて、Ｄ５０を粉砕時間で調整をした。その後、湿式粉砕で得られたスラリーを濾過して、ほとんどの水分を除去した後に、水分量を調整するために乾燥機により１３０℃で乾燥させて得られたガラス粉末を用いた。 For the glass compositions (glass powders) of Examples 21 to 24, in order to make D 50 smaller within the above-mentioned predetermined range, after the above-mentioned dry pulverization, the glass powder from which coarse particles were removed was further used with water in a ball mill. The glass powder obtained by wet pulverization was used. In order to obtain a predetermined D 50 during this wet grinding, the D 50 was adjusted by the grinding time using an alumina ball having a diameter of 5 mm. Then, the slurry obtained by wet pulverization was filtered to remove most of the water content, and then the glass powder obtained by drying at 130 ° C. with a dryer was used in order to adjust the water content.
上記で得られた例１〜１３、例２１〜２４のガラス粉末について、以下のようにして、ガラス転移点およびＤ５０を測定した。 Example obtained above 1-13, the glass powder examples 21 to 24, as follows, to measure the glass transition point and D 50.
（ガラス転移点；表中「ＤＴＡ Ｔｇ」で示す。）
ガラス転移点は、示差熱分析（ＤＴＡ）により、発熱−吸熱量を示すＤＴＡ曲線の変曲点を用いて求めた。
（Ｄ５０）
例１〜１３、例２１〜２４のガラス粉末０．０２ｇをイソプロピルアルコール６０ｃｃに混ぜ、超音波分散により１分間分散させた。その後マイクロトラック測定機に試料を投入し、体積基準の５０％粒径であるＤ５０の値を測定した。
(Glass transition point; indicated by "DTA Tg" in the table)
The glass transition point was determined by differential thermal analysis (DTA) using the inflection point of the DTA curve indicating the amount of heat generated and absorbed.
(D 50 )
0.02 g of the glass powders of Examples 1 to 13 and Examples 21 to 24 were mixed with 60 cc of isopropyl alcohol and dispersed by ultrasonic dispersion for 1 minute. After that, the sample was put into a microtrack measuring machine, and the value of D 50 , which is a 50% particle size based on the volume, was measured.
なお、例１〜１３、例２１〜２４のガラス粉末を以下それぞれ、Ｇ１〜１３、Ｇ２１〜２４の略号で示す場合がある。ガラス組成、ガラス粉末の略号、ガラス転移点、Ｄ５０の測定結果を、表１〜表３に示す。表１〜表３において空欄はその成分を含有しないことを意味する。後述の表４〜表６においても同様である。 The glass powders of Examples 1 to 13 and Examples 21 to 24 may be referred to by the abbreviations G1 to 13 and G21 to 24, respectively. Glass composition, abbreviation of the glass powder, the glass transition point, the measurement result of the D 50, shown in Tables 1 to 3. In Tables 1 to 3, blanks mean that the component is not contained. The same applies to Tables 4 to 6 described later.
［例３１〜４６、例５１〜５３］
上記で得られた第１のガラス粉末（Ｇ１〜Ｇ９）、比較例用のガラス粉末（Ｇ１０〜Ｇ１３）および第２のガラス粉末（Ｇ２１〜Ｇ２４）を用いて、表４〜表６に組成を示す例３１〜４６、例５１〜５３のガラス組成物（ガラス粉末）を製造した。例３１〜４６のガラス粉末については、表４および表５に示す第１のガラス粉末または比較例用のガラス粉末と、第２のガラス粉末を質量比１：１で混合して製造した。例５１〜５３のガラス粉末については、第１のガラスＧ７と第２のガラスＧ２１を表６に示す割合で混合し製造した。各例において、混合はＶミキサーにより１時間行った。
[Examples 31-46, 51-53]
Using the first glass powders (G1 to G9) obtained above, the glass powders for comparative examples (G10 to G13), and the second glass powders (G21 to G24), the compositions are shown in Tables 4 to 6. The glass compositions (glass powders) of Examples 31 to 46 and Examples 51 to 53 shown were produced. The glass powders of Examples 31 to 46 were produced by mixing the first glass powder shown in Tables 4 and 5 or the glass powder for Comparative Example with the second glass powder at a mass ratio of 1: 1. The glass powders of Examples 51 to 53 were produced by mixing the first glass G7 and the second glass G21 at the ratios shown in Table 6. In each example, mixing was carried out with a V mixer for 1 hour.
（評価）
例３１〜４６、例５１〜５３のガラス粉末を用いて、Ａｌ電極形成用導電ペーストを製造し、電極形成時の絶縁膜貫通性を評価した。この際、絶縁膜は窒化珪素層と酸化アルミニウム層の２層からなるものを用いた。その結果を表４〜表６に示す。
(Evaluation)
Using the glass powders of Examples 31 to 46 and Examples 51 to 53, conductive pastes for forming Al electrodes were produced, and the penetrability of the insulating film during electrode formation was evaluated. At this time, the insulating film used was composed of two layers, a silicon nitride layer and an aluminum oxide layer. The results are shown in Tables 4 to 6.
（１）Ａｌ電極形成用導電ペーストの作製
例３１〜４６、例５１〜５３のガラス粉末を含有するＡｌ電極形成用導電ペーストを以下の方法で作製した。
(1) Preparation of Conductive Paste for Forming Al Electrodes The conductive paste for forming an Al electrode containing the glass powders of Examples 31 to 46 and Examples 51 to 53 was prepared by the following method.
まず、エチルセルロース１０質量部にブチルジグリコールアセテート９０質量部を混合し、８５℃で２時間撹拌して有機ビヒクルを調製した。次に、こうして得られた有機ビヒクル２１質量部を、Ａｌ粉末（東洋アルミニウム社製）７９質量部に混合した後、擂潰機により１０分間混練した。その後、ガラス粉末を、Ａｌ粉末１００質量部に対して５質量部の割合で配合し、さらに擂潰機により６０分間混練しＡｌ電極形成用導電ペーストとした。 First, 90 parts by mass of butyl diglycol acetate was mixed with 10 parts by mass of ethyl cellulose and stirred at 85 ° C. for 2 hours to prepare an organic vehicle. Next, 21 parts by mass of the organic vehicle thus obtained was mixed with 79 parts by mass of Al powder (manufactured by Toyo Aluminum K.K.), and then kneaded with a grinder for 10 minutes. Then, the glass powder was mixed in a ratio of 5 parts by mass with respect to 100 parts by mass of the Al powder, and further kneaded with a grinder for 60 minutes to obtain a conductive paste for forming an Al electrode.
（２）Ａｌ電極の作製および絶縁膜貫通性の評価
上記で作製したＡｌ電極形成用導電ペーストをそれぞれ用いて、以下のようにして半導体基板上に絶縁膜（窒化珪素層と酸化アルミニウム層から成る２層膜）を介してＡｌ電極を形成し、その際の絶縁膜貫通性について評価した。
(2) Fabrication of Al Electrode and Evaluation of Insulation Film Penetration Using the conductive paste for forming the Al electrode prepared above, the insulating film (consisting of a silicon nitride layer and an aluminum oxide layer) is formed on the semiconductor substrate as follows. An Al electrode was formed via the two-layer film), and the penetrability of the insulating film at that time was evaluated.
１６０μｍの厚みにスライスされたｐ型の結晶系Ｓｉ半導体基板を用いて、まず、基板のスライス面を洗浄するために、表面をフッ酸でごく微量程度エッチング処理した。その後、受光面側の結晶系Ｓｉ半導体基板表面にウエットエッチング法を用いて、光反射率を低減させるような凹凸構造を形成した。次に、半導体基板の受光面にｎ型層を拡散にて形成した。ｎ型化のドーピング元素としてはＰを用いた。次に、半導体基板のｎ型層に対して裏面（ｐ型Ｓｉ基板の裏面）に絶縁膜を形成した。絶縁膜の材料としては、おもに、窒化珪素と酸化アルミニウムを用い、プラズマＣＶＤにて酸化アルミニウム層を１０ｎｍの厚さに形成した後にその上層に酸化珪素層を１２０ｎｍの厚さに形成した。 Using a p-type crystalline Si semiconductor substrate sliced to a thickness of 160 μm, the surface was first etched with hydrofluoric acid to a very small amount in order to clean the sliced surface of the substrate. After that, a wet etching method was used on the surface of the crystalline Si semiconductor substrate on the light receiving surface side to form a concavo-convex structure for reducing the light reflectance. Next, an n-type layer was formed by diffusion on the light receiving surface of the semiconductor substrate. P was used as the n-type doping element. Next, an insulating film was formed on the back surface (the back surface of the p-type Si substrate) with respect to the n-type layer of the semiconductor substrate. Silicon nitride and aluminum oxide were mainly used as the material of the insulating film, and the aluminum oxide layer was formed to a thickness of 10 nm by plasma CVD, and then the silicon oxide layer was formed to a thickness of 120 nm on the upper layer.
次に、絶縁膜上に上記で得られたＡｌ電極形成用導電ペーストを３２５メッシュのスクリーン印刷により図２に示すパターン状、すなわち１０ｍｍ×１０ｍｍの正方形のパターンＰ１と、パターンＰ１の１辺から１ｍｍずつ間隔を開けて、４個の１ｍｍ×１０ｍｍの長方形のパターンＰ２、Ｐ３、Ｐ４、Ｐ５がその順に上記１辺にそれぞれの長辺が平行となるように配置されたパターン形状に塗布した。その後、赤外光加熱式ベルト炉を用いてピーク温度が８００℃で１００秒間の焼成を行い、Ａｌ電極を形成した。 Next, the conductive paste for forming the Al electrode obtained above was screen-printed on the insulating film in a pattern of 325 mesh, that is, a square pattern P1 of 10 mm × 10 mm and 1 mm from one side of the pattern P1. Four 1 mm × 10 mm rectangular patterns P2, P3, P4, and P5 were applied to the pattern shapes arranged in this order so that their long sides were parallel to each other at intervals. Then, using an infrared light heating type belt furnace, firing was performed at a peak temperature of 800 ° C. for 100 seconds to form an Al electrode.
（２−１）貫通性評価（１）
上記で得られた、ｐ型層側に絶縁膜（窒化珪素層と酸化アルミニウム層から成る２層膜）を介して形成されたＡｌ電極を有するｐ型Ｓｉ半導体基板とＡｌ電極との接触抵抗Ｒｃ［Ω］を評価した。接触抵抗Ｒｃ［Ω］は、図２のパターンＰ１にテスターの陽極側を固定させて、パターンＰ２、Ｐ３、Ｐ４、Ｐ５のそれぞれの位置にテスターの陰極側を当てて電気抵抗を測定し、接触抵抗Ｒｃ［Ω］と、シート抵抗成分Ｒｓ［Ω］とを分離させることにより求めた。
(2-1) Penetration evaluation (1)
Contact resistance Rc between the p-type Si semiconductor substrate obtained above and the Al electrode having an Al electrode formed on the p-type layer side via an insulating film (a two-layer film composed of a silicon nitride layer and an aluminum oxide layer). [Ω] was evaluated. For the contact resistance Rc [Ω], the anode side of the tester is fixed to the pattern P1 in FIG. It was obtained by separating the resistance Rc [Ω] and the sheet resistance component Rs [Ω].
具体的には、図３に示すように、陽極と陰極間の距離Ｌ［ｍｍ］を横軸にとり、電気抵抗Ｒ［Ω］を縦軸にとったグラフに、パターンＰ１とパターンＰ２（Ｌ＝１ｍｍ）、Ｐ３（Ｌ＝３ｍｍ）、Ｐ４（Ｌ＝５ｍｍ）、Ｐ５（Ｌ＝７ｍｍ）、との間でそれぞれ測定された電気抵抗値をプロットした。得られた４プロットから近似直線を求め、該近似直線の切片の値が２Ｒｃである。図３には、例３７と例５１のガラス粉末を用いた場合に得られた近似直線が実線および破線で示されている。例３７では切片の値は５．１［Ω］であり、Ｒｃが２．６［Ω］と求められた。例５１では切片の値は２１．８［Ω］であり、Ｒｃが１０．９［Ω］と求められた。Ｒｃ［Ω］の値が小さいほど貫通性が良好と評価できる。尚、表４〜６において、Ｒｃが「×」と記載されているものは、電気抵抗値が高く測定が困難であったことを示す。 Specifically, as shown in FIG. 3, patterns P1 and P2 (L =) are shown in a graph in which the distance L [mm] between the anode and the cathode is on the horizontal axis and the electrical resistance R [Ω] is on the vertical axis. 1 mm), P3 (L = 3 mm), P4 (L = 5 mm), P5 (L = 7 mm), and the measured electrical resistance values were plotted. An approximate straight line is obtained from the obtained 4 plots, and the intercept value of the approximate straight line is 2 Rc. In FIG. 3, the approximate straight lines obtained when the glass powders of Examples 37 and 51 are used are shown by solid lines and broken lines. In Example 37, the intercept value was 5.1 [Ω], and Rc was determined to be 2.6 [Ω]. In Example 51, the intercept value was 21.8 [Ω], and Rc was determined to be 10.9 [Ω]. It can be evaluated that the smaller the value of Rc [Ω], the better the penetration. In Tables 4 to 6, when Rc is described as "x", it indicates that the electric resistance value is high and measurement is difficult.
（２−２）貫通性評価（２）
また、上記で得られた、ｐ型層側に絶縁膜（窒化珪素層と酸化アルミニウム層から成る２層膜）を介して形成されたＡｌ電極を有するｐ型Ｓｉ半導体基板を、塩酸（塩化水素の３５〜３８％水溶液）と水を１：１の質量比で混合した水溶液中に２４時間浸して、該基板からＡｌ電極を除去した。その後、光学顕微鏡（５００倍）により絶縁膜が除去されているかどうかを確認し、貫通性を以下の基準により評価した。
(2-2) Penetration evaluation (2)
Further, the p-type Si semiconductor substrate obtained above, which has an Al electrode formed via an insulating film (a two-layer film composed of a silicon nitride layer and an aluminum oxide layer) on the p-type layer side, is subjected to hydrochloric acid (hydrogen chloride). (35-38% aqueous solution) and water were immersed in an aqueous solution mixed at a mass ratio of 1: 1 for 24 hours to remove the Al electrode from the substrate. Then, it was confirmed by an optical microscope (500 times) whether or not the insulating film was removed, and the penetrability was evaluated according to the following criteria.
○；絶縁膜が除去されている箇所が確認できた。
×；絶縁膜が除去されている箇所が確認できなかった。
◯; It was confirmed that the insulating film was removed.
X: The part where the insulating film was removed could not be confirmed.
貫通性の評価結果を表４〜表６に示す。また、図４に例３７（実施例）のガラス組成物を含有するＡｌ電極形成用導電ペーストを用いて上記のようにしてＡｌ電極を形成後、Ａｌ電極が除去されたｐ型Ｓｉ半導体基板のｐ型層側表面の光学顕微鏡（５００倍）写真を示す。図４の写真によれば、絶縁膜が除去されている箇所が確認できた。すなわち、上記Ａｌ電極形成時に、絶縁膜を構成する窒化珪素層と酸化アルミニウム層から成る２層膜に例３７のガラス組成物が反応して、得られたＡｌ電極がＳｉ半導体基板まで到達したことが分かった。図５に例５１（比較例）のガラス組成物を含有するＡｌ電極形成用導電ペーストを用いて上記のようにしてＡｌ電極を形成後、Ａｌ電極が除去されたｐ型Ｓｉ半導体基板のｐ型層側表面の光学顕微鏡（５００倍）写真を示す。図５の写真によれば、絶縁膜が除去されている箇所が確認できなかった。すなわち、例５１のガラス組成物は絶縁膜を構成する窒化珪素層と酸化アルミニウム層から成る２層膜との反応性が乏しく、そのため上記Ａｌ電極形成時に、絶縁膜とガラス組成物が十分反応せず、得られたＡｌ電極がＳｉ半導体基板にまで到達していなかったことが分かった。 The evaluation results of penetrability are shown in Tables 4 to 6. Further, in FIG. 4, the p-type Si semiconductor substrate from which the Al electrode was removed after the Al electrode was formed as described above using the conductive paste for forming the Al electrode containing the glass composition of Example 37 (Example). An optical microscope (500x) photograph of the surface on the p-type layer side is shown. According to the photograph of FIG. 4, it was confirmed that the insulating film was removed. That is, at the time of forming the Al electrode, the glass composition of Example 37 reacted with the two-layer film composed of the silicon nitride layer and the aluminum oxide layer constituting the insulating film, and the obtained Al electrode reached the Si semiconductor substrate. I understood. In FIG. 5, the p-type Si semiconductor substrate of the p-type Si semiconductor substrate from which the Al electrode was removed after the Al electrode was formed as described above using the conductive paste for forming the Al electrode containing the glass composition of Example 51 (Comparative Example). An optical microscope (500x) photograph of the surface on the layer side is shown. According to the photograph of FIG. 5, the portion where the insulating film was removed could not be confirmed. That is, the glass composition of Example 51 has poor reactivity with the two-layer film composed of the silicon nitride layer and the aluminum oxide layer constituting the insulating film, and therefore, the insulating film and the glass composition sufficiently react with each other when the Al electrode is formed. It was found that the obtained Al electrode did not reach the Si semiconductor substrate.
表４〜表６および図４、５から明らかなように、実施例である例３１〜４１、５２のガラス組成物は太陽電池のＡｌ電極を形成するために好適なものである。 As is clear from Tables 4 to 6 and FIGS. 4 and 5, the glass compositions of Examples 31 to 41 and 52 of Examples are suitable for forming the Al electrode of the solar cell.
［太陽電池としての評価］
上記例３１〜４６のガラス粉末をそれぞれ含有するＡｌ電極形成用導電ペーストを用いて製造した太陽電池の変換効率を、ソーラシミュレータ（共進電機社製、ＫＳＸ−３０００H）を用いて測定した。具体的には、ソーラシミュレータに太陽電池を設置し、分光特性ＡＭ１．５Ｇの基準太陽光線によって、ＪＩＳ Ｃ８９０４−９（２０１７年）に準拠して電流電圧特性を測定して、各太陽電池の変換効率を導き出した。得られた変換効率［％］の結果を表４および表５に併せて示す。
比較例である例４２はＣｕＯを含むため、これを用いて得られた太陽電池は、実施例である例３１〜４１を用いて得られた太陽電池と比較して、変換効率が割合として１０％程度低かった。また、貫通性に劣る比較例である例４３〜４６を用いて得られた太陽電池は、実施例である例３１〜４１を用いて得られた太陽電池と比較して、顕著に変換効率が低かった。
[Evaluation as a solar cell]
The conversion efficiency of the solar cell produced by using the conductive paste for forming an Al electrode containing the glass powders of Examples 31 to 46 was measured using a solar simulator (KSX-3000H, manufactured by Kyoshin Electric Co., Ltd.). Specifically, a solar cell is installed in a solar simulator, and the current-voltage characteristics are measured in accordance with JIS C8904-9 (2017) with a reference sunlight having a spectral characteristic of AM1.5G, and conversion of each solar cell is performed. Derived efficiency. The results of the obtained conversion efficiency [%] are also shown in Tables 4 and 5.
Since Example 42, which is a comparative example, contains CuO, the solar cell obtained by using the CuO has a conversion efficiency of 10 as a percentage as compared with the solar cell obtained by using Examples 31 to 41 of Examples. It was about% low. Further, the solar cells obtained by using Examples 43 to 46, which are inferior in penetrability, have significantly higher conversion efficiencies than the solar cells obtained by using Examples 31 to 41, which are Examples. It was low.
本発明を詳細にまた特定の実施態様を参照して説明したが、本発明の精神と範囲を逸脱することなく様々な変更や修正を加えることができることは、当業者にとって明らかである。 Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.
１０…太陽電池、１…ｐ型Ｓｉ（半導体）基板、１ａ…ｎ＋層、１ｂ…ｐ層、２Ａ，２Ｂ…絶縁膜、３…Ａｇ電極、４…Ａｌ電極、５…Ａｌ−Ｓｉ合金層、６…ＢＳＦ層。 10 ... Solar cell, 1 ... p-type Si (semiconductor) substrate, 1a ... n + layer, 1b ... p layer, 2A, 2B ... Insulating film, 3 ... Ag electrode, 4 ... Al electrode, 5 ... Al—Si alloy layer , 6 ... BSF layer.
Claims (13)
Ｂｉ２Ｏ３を３％以上１９％以下、
Ｂ２Ｏ３を２０％以上７０％以下、
ＳｉＯ２を１％以上３０％以下、
Ｋ２Ｏを３％以上２０％以下、
ＣａＯを３％以上２０％以下、
ＢａＯを１％以上２０％以下、
含有し、実質的にＰｂＯとＣｕＯとを含まないガラス組成物。 In molar% notation based on oxides
Bi 2 O 3 3% or more and 19% or less,
B 2 O 3 20% or more and 70% or less,
SiO 2 is 1% or more and 30% or less,
K 2 O 3% or more and 20% or less,
CaO 3% or more and 20% or less,
BaO 1% or more and 20% or less,
A glass composition containing and substantially free of PbO and CuO.
Ｂ２Ｏ３を３５％以上６０％以下、
Ｋ２Ｏを１％以上４０％以下、
ＣａＯを３％以上３０％以下、
ＢａＯを２％以上２５％以下、
ＳｉＯ２を５％以上１０％以下含有し、実質的にＰｂＯとＣｕＯとを含まない第１のガラス組成物と、
酸化物基準のモル％表記で、
Ｂｉ２Ｏ３を５％以上６０％以下、
Ｂ２Ｏ３を１５％以上８０％以下含有し、実質的にＰｂＯとＣｕＯとを含まない第２のガラス組成物と
を混合する工程を含む、ガラス組成物の製造方法。 In molar% notation based on oxides
B 2 O 3 35% or more and 60% or less,
K 2 O 1% or more and 40% or less,
CaO 3% or more and 30% or less,
BaO is 2% or more and 25% or less,
A first glass composition containing 5% or more and 10% or less of SiO 2 and substantially free of PbO and CuO.
In molar% notation based on oxides
Bi 2 O 3 5% or more and 60% or less,
A method for producing a glass composition, which comprises a step of mixing a second glass composition containing B 2 O 3 in an amount of 15% or more and 80% or less and substantially free of PbO and CuO.
前記シリコン基板の前記太陽光受光面に設けられた第１の絶縁膜と、
前記シリコン基板の前記太陽光受光面とは反対側の面に設けられた第２の絶縁膜と、
前記第１の絶縁膜の一部を貫通して前記シリコン基板に接触する第１の電極と、
前記第２の絶縁膜の一部を貫通して前記シリコン基板に接触する第２の電極と、
を備える太陽電池であって、
前記第１の電極は、Ａｌ、Ａｇ、Ｃｕ、Ａｕ、ＰｄおよびＰｔからなる群から選択される少なくとも１種を含む第１の金属と、第１のガラスとを含み、
前記第２の電極は、Ａｌ、Ａｇ、Ｃｕ、Ａｕ、ＰｄおよびＰｔからなる群から選択される少なくとも１種を含む第２の金属と、
酸化物基準のモル％表記で、
Ｂｉ２Ｏ３を３％以上１９％以下、
Ｂ２Ｏ３を２０％以上７０％以下、
ＳｉＯ２を１％以上３０％以下、
Ｋ２Ｏを３％以上２０％以下、
ＣａＯを３％以上２０％以下、
ＢａＯを１％以上２０％以下、
含有し、実質的にＰｂＯとＣｕＯとを含まない第２のガラスを含む
太陽電池。 A silicon substrate with a sunlight receiving surface and
A first insulating film provided on the sunlight receiving surface of the silicon substrate and
A second insulating film provided on the surface of the silicon substrate opposite to the sunlight receiving surface, and
A first electrode that penetrates a part of the first insulating film and comes into contact with the silicon substrate.
A second electrode that penetrates a part of the second insulating film and comes into contact with the silicon substrate.
It is a solar cell equipped with
The first electrode comprises a first metal containing at least one selected from the group consisting of Al, Ag, Cu, Au, Pd and Pt, and a first glass.
The second electrode comprises a second metal containing at least one selected from the group consisting of Al, Ag, Cu, Au, Pd and Pt.
In molar% notation based on oxides
Bi 2 O 3 3% or more and 19% or less,
B 2 O 3 20% or more and 70% or less,
SiO 2 is 1% or more and 30% or less,
K 2 O 3% or more and 20% or less,
CaO 3% or more and 20% or less,
BaO 1% or more and 20% or less,
A solar cell containing a second glass that contains and is substantially free of PbO and CuO.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2019104493A JP7444552B2 (en) | 2019-06-04 | 2019-06-04 | Glass composition, method for producing glass composition, conductive paste, and solar cell |
| CN202010488206.9A CN112028494B (en) | 2019-06-04 | 2020-06-02 | Glass composition, method for producing glass composition, conductive paste, and solar cell |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2019104493A JP7444552B2 (en) | 2019-06-04 | 2019-06-04 | Glass composition, method for producing glass composition, conductive paste, and solar cell |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2020198380A true JP2020198380A (en) | 2020-12-10 |
| JP7444552B2 JP7444552B2 (en) | 2024-03-06 |
Family
ID=73579434
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2019104493A Active JP7444552B2 (en) | 2019-06-04 | 2019-06-04 | Glass composition, method for producing glass composition, conductive paste, and solar cell |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP7444552B2 (en) |
| CN (1) | CN112028494B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114751647B (en) * | 2022-03-29 | 2023-06-20 | 华南理工大学 | Glass frit easy to grind and preparation method and application thereof |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006261350A (en) * | 2005-03-16 | 2006-09-28 | Tdk Corp | Resistor paste and resistor |
| JP2012180261A (en) * | 2011-02-10 | 2012-09-20 | Central Glass Co Ltd | Electroconductive paste and solar cell element obtained using the same |
| JP2013018666A (en) * | 2011-07-08 | 2013-01-31 | Nippon Electric Glass Co Ltd | Electrode formation glass and electrode formation material |
| JP2014187345A (en) * | 2013-02-20 | 2014-10-02 | Toyo Aluminium Kk | Paste composition, method for manufacturing solar battery element, and solar battery element |
| JP2015107892A (en) * | 2013-12-05 | 2015-06-11 | 旭硝子株式会社 | Glass composition and light take-out layer |
| CN105261669A (en) * | 2014-05-13 | 2016-01-20 | E.I.内穆尔杜邦公司 | Method of manufacturing a solar cell electrode |
| JP2016213284A (en) * | 2015-05-01 | 2016-12-15 | 東洋アルミニウム株式会社 | Aluminum paste composition for PERC type solar cell |
| US20170040470A1 (en) * | 2015-08-07 | 2017-02-09 | E I Du Pont De Nemours And Company | Conductive paste composition and semiconductor devices made therewith |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5649290B2 (en) * | 2009-07-30 | 2015-01-07 | 株式会社ノリタケカンパニーリミテド | Lead-free conductive composition for solar cell electrode |
| JP5540810B2 (en) | 2010-03-24 | 2014-07-02 | 三菱マテリアル株式会社 | Conductive composition, method for producing solar cell using the same, and solar cell |
| JP6067726B2 (en) | 2012-09-26 | 2017-01-25 | ヘレウス プレシャス メタルズ ノース アメリカ コンショホーケン エルエルシー | Conductive paste and solar cell |
-
2019
- 2019-06-04 JP JP2019104493A patent/JP7444552B2/en active Active
-
2020
- 2020-06-02 CN CN202010488206.9A patent/CN112028494B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006261350A (en) * | 2005-03-16 | 2006-09-28 | Tdk Corp | Resistor paste and resistor |
| JP2012180261A (en) * | 2011-02-10 | 2012-09-20 | Central Glass Co Ltd | Electroconductive paste and solar cell element obtained using the same |
| JP2013018666A (en) * | 2011-07-08 | 2013-01-31 | Nippon Electric Glass Co Ltd | Electrode formation glass and electrode formation material |
| JP2014187345A (en) * | 2013-02-20 | 2014-10-02 | Toyo Aluminium Kk | Paste composition, method for manufacturing solar battery element, and solar battery element |
| JP2015107892A (en) * | 2013-12-05 | 2015-06-11 | 旭硝子株式会社 | Glass composition and light take-out layer |
| CN105261669A (en) * | 2014-05-13 | 2016-01-20 | E.I.内穆尔杜邦公司 | Method of manufacturing a solar cell electrode |
| JP2016213284A (en) * | 2015-05-01 | 2016-12-15 | 東洋アルミニウム株式会社 | Aluminum paste composition for PERC type solar cell |
| US20170040470A1 (en) * | 2015-08-07 | 2017-02-09 | E I Du Pont De Nemours And Company | Conductive paste composition and semiconductor devices made therewith |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112028494A (en) | 2020-12-04 |
| CN112028494B (en) | 2024-05-14 |
| JP7444552B2 (en) | 2024-03-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI778207B (en) | Glass, glass powder, conductive paste and solar cells | |
| EP3405961B1 (en) | Conductive paste, method, electrode and solar cell | |
| JP6966950B2 (en) | Glass, glass manufacturing methods, conductive pastes and solar cells | |
| JP2018078120A (en) | Thick-film composition containing antimony oxides and their use in manufacture of semiconductor devices | |
| JP2017218335A (en) | Glass, conductive paste and solar battery | |
| JP6958257B2 (en) | Glass compositions, glass powders, conductive pastes and solar cells | |
| JP7444552B2 (en) | Glass composition, method for producing glass composition, conductive paste, and solar cell | |
| JP2020083670A (en) | Glass composition, glass powder, conductive paste, and solar battery | |
| JP6720712B2 (en) | Glass powder, conductive paste and solar cell | |
| JP7088811B2 (en) | Glass, glass powder, conductive paste and solar cells | |
| TWI841623B (en) | Glass, glass powder, conductive paste and solar cell | |
| CN116332500A (en) | Glass, conductive paste and solar cell | |
| EP3289592B1 (en) | Conductive paste, electrode and solar cell | |
| KR20200123643A (en) | Glass frit composition for forming solar cell electrode, and paste composition including the same | |
| JP2023097338A (en) | Glass, conductive paste and solar cell | |
| CN116332501A (en) | Glass, conductive paste and solar cell | |
| JP2023004853A (en) | Glass, glass powder, conductive paste and solar cell | |
| CN115521064A (en) | Glass, glass powder, conductive paste and solar cell | |
| KR20210025483A (en) | Glass composition, glass powder and conductive paste | |
| CN112441738A (en) | Glass composition, glass powder and conductive paste | |
| JP6702011B2 (en) | Glass powder, conductive paste and solar cell | |
| KR20230055847A (en) | Glass frit composition for forming solar cell electrode, solar cell electrode formed by using the same glass composition, and solar cell including the same electrode | |
| CN115019997A (en) | Conductive paste, solar cell prepared from conductive paste and manufacturing method of solar cell | |
| KR20190010279A (en) | Glass frit for forming solar cell electrode, paste composition including the same glass frit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20220519 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20230228 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20230307 |
|
| A601 | Written request for extension of time |
Free format text: JAPANESE INTERMEDIATE CODE: A601 Effective date: 20230508 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20230524 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20230822 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20231020 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20240130 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20240222 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 7444552 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |