JP6369747B2 - Electroluminescent device - Google Patents
Electroluminescent device Download PDFInfo
- Publication number
- JP6369747B2 JP6369747B2 JP2014082630A JP2014082630A JP6369747B2 JP 6369747 B2 JP6369747 B2 JP 6369747B2 JP 2014082630 A JP2014082630 A JP 2014082630A JP 2014082630 A JP2014082630 A JP 2014082630A JP 6369747 B2 JP6369747 B2 JP 6369747B2
- Authority
- JP
- Japan
- Prior art keywords
- layer
- anthracene derivative
- light emitting
- electron
- injection layer
- 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.)
- Expired - Fee Related
Links
- 239000010410 layer Substances 0.000 claims description 133
- 238000002347 injection Methods 0.000 claims description 73
- 239000007924 injection Substances 0.000 claims description 73
- 150000001454 anthracenes Chemical class 0.000 claims description 55
- 150000001875 compounds Chemical class 0.000 claims description 49
- 230000005525 hole transport Effects 0.000 claims description 17
- 239000012044 organic layer Substances 0.000 claims description 12
- -1 polycyclic aromatic compound Chemical class 0.000 claims description 10
- 125000004093 cyano group Chemical group *C#N 0.000 claims description 7
- 125000005647 linker group Chemical group 0.000 claims description 6
- 125000003118 aryl group Chemical group 0.000 claims description 4
- 125000000623 heterocyclic group Chemical group 0.000 claims description 4
- 125000005577 anthracene group Chemical group 0.000 claims 1
- 239000000758 substrate Substances 0.000 description 23
- 239000000463 material Substances 0.000 description 21
- 230000004888 barrier function Effects 0.000 description 20
- 239000002019 doping agent Substances 0.000 description 18
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 16
- 238000000151 deposition Methods 0.000 description 16
- 230000008021 deposition Effects 0.000 description 16
- 239000000370 acceptor Substances 0.000 description 14
- 239000011521 glass Substances 0.000 description 13
- 125000001424 substituent group Chemical group 0.000 description 13
- PQXKHYXIUOZZFA-UHFFFAOYSA-M lithium fluoride Chemical compound [Li+].[F-] PQXKHYXIUOZZFA-UHFFFAOYSA-M 0.000 description 12
- 238000007740 vapor deposition Methods 0.000 description 12
- 239000010408 film Substances 0.000 description 9
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 8
- UJOBWOGCFQCDNV-UHFFFAOYSA-N 9H-carbazole Chemical compound C1=CC=C2C3=CC=CC=C3NC2=C1 UJOBWOGCFQCDNV-UHFFFAOYSA-N 0.000 description 6
- 239000000969 carrier Substances 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 6
- TXCDCPKCNAJMEE-UHFFFAOYSA-N dibenzofuran Chemical compound C1=CC=C2C3=CC=CC=C3OC2=C1 TXCDCPKCNAJMEE-UHFFFAOYSA-N 0.000 description 6
- 150000002430 hydrocarbons Chemical class 0.000 description 6
- 229910000476 molybdenum oxide Inorganic materials 0.000 description 6
- PQQKPALAQIIWST-UHFFFAOYSA-N oxomolybdenum Chemical compound [Mo]=O PQQKPALAQIIWST-UHFFFAOYSA-N 0.000 description 6
- 239000010409 thin film Substances 0.000 description 6
- 239000007772 electrode material Substances 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 4
- 238000009835 boiling Methods 0.000 description 4
- 239000003599 detergent Substances 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 230000007935 neutral effect Effects 0.000 description 4
- 230000001681 protective effect Effects 0.000 description 4
- 238000001552 radio frequency sputter deposition Methods 0.000 description 4
- TVIVIEFSHFOWTE-UHFFFAOYSA-K tri(quinolin-8-yloxy)alumane Chemical compound [Al+3].C1=CN=C2C([O-])=CC=CC2=C1.C1=CN=C2C([O-])=CC=CC2=C1.C1=CN=C2C([O-])=CC=CC2=C1 TVIVIEFSHFOWTE-UHFFFAOYSA-K 0.000 description 4
- 238000004506 ultrasonic cleaning Methods 0.000 description 4
- XHCLAFWTIXFWPH-UHFFFAOYSA-N [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] XHCLAFWTIXFWPH-UHFFFAOYSA-N 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 3
- 230000006798 recombination Effects 0.000 description 3
- 238000005215 recombination Methods 0.000 description 3
- 125000005259 triarylamine group Chemical group 0.000 description 3
- 238000007738 vacuum evaporation Methods 0.000 description 3
- 229910001935 vanadium oxide Inorganic materials 0.000 description 3
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- 229910000846 In alloy Inorganic materials 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 2
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 description 2
- NRCMAYZCPIVABH-UHFFFAOYSA-N Quinacridone Chemical compound N1C2=CC=CC=C2C(=O)C2=C1C=C1C(=O)C3=CC=CC=C3NC1=C2 NRCMAYZCPIVABH-UHFFFAOYSA-N 0.000 description 2
- MWPLVEDNUUSJAV-UHFFFAOYSA-N anthracene Chemical compound C1=CC=CC2=CC3=CC=CC=C3C=C21 MWPLVEDNUUSJAV-UHFFFAOYSA-N 0.000 description 2
- 229910052791 calcium Inorganic materials 0.000 description 2
- 239000011575 calcium Substances 0.000 description 2
- 239000000470 constituent Substances 0.000 description 2
- 239000000975 dye Substances 0.000 description 2
- 150000004820 halides Chemical class 0.000 description 2
- 229910052744 lithium Inorganic materials 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- QGLKJKCYBOYXKC-UHFFFAOYSA-N nonaoxidotritungsten Chemical compound O=[W]1(=O)O[W](=O)(=O)O[W](=O)(=O)O1 QGLKJKCYBOYXKC-UHFFFAOYSA-N 0.000 description 2
- 239000011368 organic material Substances 0.000 description 2
- 239000002985 plastic film Substances 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- XSCHRSMBECNVNS-UHFFFAOYSA-N quinoxaline Chemical compound N1=CC=NC2=CC=CC=C21 XSCHRSMBECNVNS-UHFFFAOYSA-N 0.000 description 2
- 239000002356 single layer Substances 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 238000004544 sputter deposition Methods 0.000 description 2
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 2
- 229910001887 tin oxide Inorganic materials 0.000 description 2
- 229910001930 tungsten oxide Inorganic materials 0.000 description 2
- 239000011787 zinc oxide Substances 0.000 description 2
- GOLORTLGFDVFDW-UHFFFAOYSA-N 3-(1h-benzimidazol-2-yl)-7-(diethylamino)chromen-2-one Chemical compound C1=CC=C2NC(C3=CC4=CC=C(C=C4OC3=O)N(CC)CC)=NC2=C1 GOLORTLGFDVFDW-UHFFFAOYSA-N 0.000 description 1
- GAMYYCRTACQSBR-UHFFFAOYSA-N 4-azabenzimidazole Chemical compound C1=CC=C2NC=NC2=N1 GAMYYCRTACQSBR-UHFFFAOYSA-N 0.000 description 1
- KDCGOANMDULRCW-UHFFFAOYSA-N 7H-purine Chemical compound N1=CNC2=NC=NC2=C1 KDCGOANMDULRCW-UHFFFAOYSA-N 0.000 description 1
- 229910001316 Ag alloy Inorganic materials 0.000 description 1
- 229910001148 Al-Li alloy Inorganic materials 0.000 description 1
- KHNYNFUTFKJLDD-UHFFFAOYSA-N Benzo[j]fluoranthene Chemical compound C1=CC(C=2C3=CC=CC=C3C=CC=22)=C3C2=CC=CC3=C1 KHNYNFUTFKJLDD-UHFFFAOYSA-N 0.000 description 1
- 229910000882 Ca alloy Inorganic materials 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 1
- 229910000799 K alloy Inorganic materials 0.000 description 1
- 229910000861 Mg alloy Inorganic materials 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- CZPWVGJYEJSRLH-UHFFFAOYSA-N Pyrimidine Chemical compound C1=CN=CN=C1 CZPWVGJYEJSRLH-UHFFFAOYSA-N 0.000 description 1
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 1
- DGEZNRSVGBDHLK-UHFFFAOYSA-N [1,10]phenanthroline Chemical compound C1=CN=C2C3=NC=CC=C3C=CC2=C1 DGEZNRSVGBDHLK-UHFFFAOYSA-N 0.000 description 1
- JFBZPFYRPYOZCQ-UHFFFAOYSA-N [Li].[Al] Chemical compound [Li].[Al] JFBZPFYRPYOZCQ-UHFFFAOYSA-N 0.000 description 1
- JHYLKGDXMUDNEO-UHFFFAOYSA-N [Mg].[In] Chemical compound [Mg].[In] JHYLKGDXMUDNEO-UHFFFAOYSA-N 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 1
- 150000001342 alkaline earth metals Chemical class 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- RGKMZNDDOBAZGW-UHFFFAOYSA-N aluminum calcium Chemical compound [Al].[Ca] RGKMZNDDOBAZGW-UHFFFAOYSA-N 0.000 description 1
- SNAAJJQQZSMGQD-UHFFFAOYSA-N aluminum magnesium Chemical compound [Mg].[Al] SNAAJJQQZSMGQD-UHFFFAOYSA-N 0.000 description 1
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 description 1
- 229910001634 calcium fluoride Inorganic materials 0.000 description 1
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 1
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 1
- 239000000292 calcium oxide Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 229910000423 chromium oxide Inorganic materials 0.000 description 1
- 238000010549 co-Evaporation Methods 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 239000003086 colorant Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000005401 electroluminescence Methods 0.000 description 1
- 238000010893 electron trap Methods 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 150000002219 fluoranthenes Chemical class 0.000 description 1
- 239000007850 fluorescent dye Substances 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 229910052738 indium Inorganic materials 0.000 description 1
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 description 1
- LHJOPRPDWDXEIY-UHFFFAOYSA-N indium lithium Chemical compound [Li].[In] LHJOPRPDWDXEIY-UHFFFAOYSA-N 0.000 description 1
- AMGQUBHHOARCQH-UHFFFAOYSA-N indium;oxotin Chemical compound [In].[Sn]=O AMGQUBHHOARCQH-UHFFFAOYSA-N 0.000 description 1
- 150000002484 inorganic compounds Chemical class 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 238000007733 ion plating Methods 0.000 description 1
- 238000010884 ion-beam technique Methods 0.000 description 1
- 239000001989 lithium alloy Substances 0.000 description 1
- FUJCRWPEOMXPAD-UHFFFAOYSA-N lithium oxide Chemical compound [Li+].[Li+].[O-2] FUJCRWPEOMXPAD-UHFFFAOYSA-N 0.000 description 1
- 229910001947 lithium oxide Inorganic materials 0.000 description 1
- ORUIBWPALBXDOA-UHFFFAOYSA-L magnesium fluoride Chemical compound [F-].[F-].[Mg+2] ORUIBWPALBXDOA-UHFFFAOYSA-L 0.000 description 1
- 229910001635 magnesium fluoride Inorganic materials 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- 239000000395 magnesium oxide Substances 0.000 description 1
- SJCKRGFTWFGHGZ-UHFFFAOYSA-N magnesium silver Chemical compound [Mg].[Ag] SJCKRGFTWFGHGZ-UHFFFAOYSA-N 0.000 description 1
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 125000004957 naphthylene group Chemical group 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910000484 niobium oxide Inorganic materials 0.000 description 1
- URLJKFSTXLNXLG-UHFFFAOYSA-N niobium(5+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Nb+5].[Nb+5] URLJKFSTXLNXLG-UHFFFAOYSA-N 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- WCPAKWJPBJAGKN-UHFFFAOYSA-N oxadiazole Chemical compound C1=CON=N1 WCPAKWJPBJAGKN-UHFFFAOYSA-N 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- DYIZHKNUQPHNJY-UHFFFAOYSA-N oxorhenium Chemical compound [Re]=O DYIZHKNUQPHNJY-UHFFFAOYSA-N 0.000 description 1
- BPUBBGLMJRNUCC-UHFFFAOYSA-N oxygen(2-);tantalum(5+) Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Ta+5].[Ta+5] BPUBBGLMJRNUCC-UHFFFAOYSA-N 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- XEXYATIPBLUGSF-UHFFFAOYSA-N phenanthro[9,10-b]pyridine-2,3,4,5,6,7-hexacarbonitrile Chemical group N1=C(C#N)C(C#N)=C(C#N)C2=C(C(C#N)=C(C(C#N)=C3)C#N)C3=C(C=CC=C3)C3=C21 XEXYATIPBLUGSF-UHFFFAOYSA-N 0.000 description 1
- 125000000843 phenylene group Chemical group C1(=C(C=CC=C1)*)* 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 229920000128 polypyrrole Polymers 0.000 description 1
- 229920000123 polythiophene Polymers 0.000 description 1
- BITYAPCSNKJESK-UHFFFAOYSA-N potassiosodium Chemical compound [Na].[K] BITYAPCSNKJESK-UHFFFAOYSA-N 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 1
- 238000006862 quantum yield reaction Methods 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 229910003449 rhenium oxide Inorganic materials 0.000 description 1
- PYWVYCXTNDRMGF-UHFFFAOYSA-N rhodamine B Chemical compound [Cl-].C=12C=CC(=[N+](CC)CC)C=C2OC2=CC(N(CC)CC)=CC=C2C=1C1=CC=CC=C1C(O)=O PYWVYCXTNDRMGF-UHFFFAOYSA-N 0.000 description 1
- YYMBJDOZVAITBP-UHFFFAOYSA-N rubrene Chemical compound C1=CC=CC=C1C(C1=C(C=2C=CC=CC=2)C2=CC=CC=C2C(C=2C=CC=CC=2)=C11)=C(C=CC=C2)C2=C1C1=CC=CC=C1 YYMBJDOZVAITBP-UHFFFAOYSA-N 0.000 description 1
- 229910052707 ruthenium Inorganic materials 0.000 description 1
- 229910001925 ruthenium oxide Inorganic materials 0.000 description 1
- WOCIAKWEIIZHES-UHFFFAOYSA-N ruthenium(iv) oxide Chemical compound O=[Ru]=O WOCIAKWEIIZHES-UHFFFAOYSA-N 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- PUZPDOWCWNUUKD-UHFFFAOYSA-M sodium fluoride Chemical compound [F-].[Na+] PUZPDOWCWNUUKD-UHFFFAOYSA-M 0.000 description 1
- KKCBUQHMOMHUOY-UHFFFAOYSA-N sodium oxide Chemical compound [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 description 1
- 229910001948 sodium oxide Inorganic materials 0.000 description 1
- 125000005504 styryl group Chemical group 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229910001936 tantalum oxide Inorganic materials 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 238000002834 transmittance Methods 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
- 238000001771 vacuum deposition Methods 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- GPPXJZIENCGNKB-UHFFFAOYSA-N vanadium Chemical compound [V]#[V] GPPXJZIENCGNKB-UHFFFAOYSA-N 0.000 description 1
- 238000001947 vapour-phase growth Methods 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 description 1
Images
Landscapes
- Electroluminescent Light Sources (AREA)
- Nitrogen And Oxygen Or Sulfur-Condensed Heterocyclic Ring Systems (AREA)
Description
本発明は、電界発光素子に関するものである。 The present invention relates to an electroluminescent device.
電界発光素子は、例えば、数Ｖ〜数十Ｖ程度の低電圧で発光が可能であり、また、蛍光性有機化合物の種類を選択することにより種々の色の発光が可能なことから、様々な発光素子、表示素子などへの応用が期待されている。 The electroluminescent element can emit light at a low voltage of, for example, several volts to several tens of volts, and can emit various colors by selecting the type of the fluorescent organic compound. Applications to light-emitting elements, display elements, and the like are expected.
電界発光素子は、陽極から正孔を、陰極から電子を注入し、それぞれを発光層まで輸送した後に、両キャリアを再結合させて発光を得るデバイスである。陽極から発光層へ正孔を注入、輸送するためには、通常０．３から１ｅＶ程度のエネルギー障壁を越えねばならず、デバイス構成に相応した電圧を必要とする。このため、青色発光素子や燐光発光素子のような障壁の大きな素子では、駆動電圧に起因する消費電力の大きさが問題であった。 An electroluminescent element is a device that emits light by injecting holes from an anode and electrons from a cathode, transporting them to a light emitting layer, and then recombining both carriers. In order to inject and transport holes from the anode to the light emitting layer, the energy barrier usually has to exceed 0.3 to 1 eV, and a voltage corresponding to the device configuration is required. For this reason, in a device with a large barrier such as a blue light-emitting device or a phosphorescent light-emitting device, the power consumption due to the drive voltage is a problem.
このようなエネルギー障壁に起因する駆動電圧を低減する目的で、電子アクセプター、あるいは電子ドナーを有機材料中にドーピングする手法が試みられている。これらのデバイスでは、有機材料を強制的に酸化、あるいは還元することで、それぞれ正孔、あるいは電子を有機層中に発生させ、注入障壁を大幅に低下することが可能となった。 In order to reduce the driving voltage due to such an energy barrier, a technique of doping an electron acceptor or an electron donor into an organic material has been attempted. In these devices, by forcibly oxidizing or reducing the organic material, holes or electrons are generated in the organic layer, respectively, and the injection barrier can be greatly reduced.
電子アクセプターを使用する場合、通常は典型的な正孔注入材料、あるいは正孔輸送材料であるトリアリールアミンにドーピングする場合がほとんどであるが、特許文献１にはアントラセン誘導体にドーピングした事例が示されている。電子アクセプターを、イオン化ポテンシャルの大きなアントラセン誘導体にドーピングして正孔注入層とし、かつ正孔輸送層にもアントラセン誘導体を用いることで、陽極から発光層までの正孔注入障壁の改善に成功している。 When an electron acceptor is used, in most cases, a typical hole injection material or a triarylamine which is a hole transport material is usually doped. However, Patent Document 1 shows an example of doping an anthracene derivative. Has been. We succeeded in improving the hole injection barrier from the anode to the light-emitting layer by doping an anthracene derivative with a large ionization potential into a hole injection layer and using an anthracene derivative in the hole transport layer. Yes.
しかしながら、正孔注入層と正孔輸送層にアントラセン誘導体を用いただけでは、陰極から発光層への電子注入障壁は残っており、更なる低電圧化の余地を残している。また、発光層と電子輸送層の障壁が残っていると、層間の障壁部にキャリアが集中して局所的な発熱が生ずることで、素子寿命が低下する問題が生じてしまう。 However, if only an anthracene derivative is used for the hole injection layer and the hole transport layer, an electron injection barrier from the cathode to the light emitting layer remains, leaving room for further voltage reduction. Further, if the barrier between the light emitting layer and the electron transport layer remains, carriers are concentrated in the barrier portion between the layers, and local heat is generated, thereby causing a problem that the device lifetime is reduced.
そこで本発明は、正孔注入層から電子注入層に至るまでの正孔および電子の注入障壁を改善することで、低電圧駆動で長寿命の電界発光素子を提供することを目的とする。 Accordingly, an object of the present invention is to provide a long-life electroluminescent device that is driven at a low voltage by improving a hole and electron injection barrier from the hole injection layer to the electron injection layer.
上記の目的を達成するため、本発明の電界発光素子は、陽極および陰極からなる一対の電極間に、少なくとも1層の発光層を含む積層された複数の有機層が挟持された電界発光素子において、前記複数の有機層の全ての層にアントラセン誘導体が含まれていることを特徴とする。 In order to achieve the above object, the electroluminescent device of the present invention is an electroluminescent device in which a plurality of stacked organic layers including at least one luminescent layer are sandwiched between a pair of electrodes consisting of an anode and a cathode. The anthracene derivative is contained in all of the plurality of organic layers.
アントラセン誘導体は、高い熱安定性や優れたキャリア輸送性から発光層のホスト材料として広く用いられている。本発明では発光層を含む全ての有機層にアントラセン誘導体を用いることで、陽極から発光層までの正孔注入障壁および陰極から発光層までの電子注入障壁を全て解消することができる。その結果、極めて低電圧で駆動が可能な電界発光素子の作成が可能となる。また、発光層と電子輸送層の障壁が解消されることで、層間へのキャリア集中による素子の寿命低下も解消することができる。 Anthracene derivatives are widely used as a host material for the light-emitting layer because of high thermal stability and excellent carrier transportability. In the present invention, by using an anthracene derivative in all organic layers including the light emitting layer, all of the hole injection barrier from the anode to the light emitting layer and the electron injection barrier from the cathode to the light emitting layer can be eliminated. As a result, it is possible to create an electroluminescent element that can be driven at an extremely low voltage. Further, since the barrier between the light emitting layer and the electron transport layer is eliminated, it is possible to eliminate a decrease in the lifetime of the device due to carrier concentration between the layers.
また、本発明の電界発光素子は、陽極と発光層との間にアントラセン誘導体を含む正孔注入層を有し、かつ前記正孔注入層に電子アクセプターがドーピングされていることを特徴とする。 The electroluminescent device of the present invention is characterized in that a hole injection layer containing an anthracene derivative is provided between the anode and the light emitting layer, and the hole injection layer is doped with an electron acceptor.
アントラセン誘導体に電子アクセプターをドーピングし、正のキャリアであるホールを強制的に発生させることで、陽極とオーミックコンタクトが可能となる。このため、陽極からの注入障壁を大幅に下げることが可能になり、陽極からアントラセン誘導体への正孔注入が可能となる。 Doping an anthracene derivative with an electron acceptor to forcibly generate holes that are positive carriers enables ohmic contact with the anode. For this reason, the injection barrier from the anode can be greatly lowered, and holes can be injected from the anode into the anthracene derivative.
また、本発明の電界発光素子は、陰極と発光層との間にアントラセン誘導体を含む電子注入層を有し、かつ前記電子注入層に電子ドナーがドーピングされていることを特徴とする。 The electroluminescent device of the present invention is characterized in that an electron injection layer containing an anthracene derivative is provided between the cathode and the light emitting layer, and the electron injection layer is doped with an electron donor.
アントラセン誘導体に電子ドナーをドーピングし、負のキャリアである電子を強制的に発生させることで、陰極とオーミックコンタクトが可能となる。このため、陰極からの注入障壁を大幅に下げることが可能になり、陰極からアントラセン誘導体への電子注入が可能となる。 Doping an anthracene derivative with an electron donor to forcibly generate electrons that are negative carriers enables ohmic contact with the cathode. For this reason, the injection barrier from the cathode can be greatly lowered, and electrons can be injected from the cathode into the anthracene derivative.
また、本発明の電界発光素子は、前記複数の有機層の全てに、同一のアントラセン誘導体が含まれていることを特徴とする。 Moreover, the electroluminescent element of the present invention is characterized in that the same anthracene derivative is contained in all of the plurality of organic layers.
アントラセン誘導体は、極端な電子受容性置換基にて置換された場合、または極端な電子供与性置換基にて置換された場合を除けば、似通ったエネルギー準位を示すが、このような場合でも０．１ｅＶ程度の障壁が生ずることがあり、電圧上昇の原因となる。しかしながら有機層の全てに、同一のアントラセン誘導体を用いることで、正孔および電子障壁はゼロとなり、最小の駆動電圧での駆動が可能となる。 Anthracene derivatives show similar energy levels except when substituted with extreme electron-accepting substituents or when substituted with extreme electron-donating substituents. A barrier of about 0.1 eV may occur, causing a voltage increase. However, by using the same anthracene derivative for all of the organic layers, the hole and electron barriers become zero, and driving with the minimum driving voltage becomes possible.
また、本発明の電界発光素子は、前記発光層が下記一般式（Ｉ）の化合物を含むことを特徴とする。
（一般式（Ｉ）におけるＡは多環芳香族化合物である。Ｌは多環芳香族化合物とシアノ基を結ぶ連結基であり、置換または無置換のアリール基、置換または無置換の複素環基を示す。ｍ、ｎ、ｘは価数を表し、１〜１０の何れかの整数である。）
Moreover, the electroluminescent element of this invention is characterized by the said light emitting layer containing the compound of the following general formula (I).
(A in the general formula (I) is a polycyclic aromatic compound. L is a linking group connecting the polycyclic aromatic compound and the cyano group, and is a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group. M, n, and x represent a valence and are any integer of 1 to 10.)
発光層を含む全ての有機層にアントラセン誘導体を用い、正孔および電子の注入障壁を解消することで低電圧駆動の電界発光素子の作成が可能となるが、その一方で素子内でのキャリアトラップ性が低下し、再結合が起こりにくくなる。この問題は、十分なキャリアトラップ性を持つ一般式（Ｉ）の化合物を発光層にドーピングすることで解消することが出来る。この結果、低電圧、長寿命で、かつ高効率な電界発光素子を作成することが可能となる。 By using anthracene derivatives in all organic layers including the light-emitting layer and eliminating the hole and electron injection barrier, it is possible to create low-voltage-driven electroluminescent devices, but on the other hand, carrier traps in the device And the recombination is less likely to occur. This problem can be solved by doping the light emitting layer with a compound of the general formula (I) having a sufficient carrier trapping property. As a result, it is possible to produce an electroluminescent element having a low voltage, a long life, and a high efficiency.
本発明によれば、正孔注入層から電子注入層に至るまでの正孔および電子の注入障壁を改善することで、低電圧駆動で長寿命の電界発光素子を提供することができる。 According to the present invention, by improving the hole and electron injection barrier from the hole injection layer to the electron injection layer, it is possible to provide a long-life electroluminescent device driven at a low voltage.
本発明の実施の形態について図１を参照しながら説明する。図１に示すように、電界発光素子１は、基板２上に、陽極３、正孔注入層４、正孔輸送層５、発光層６、電子輸送層７、電子注入層８、陰極９を順次有する。 An embodiment of the present invention will be described with reference to FIG. As shown in FIG. 1, the electroluminescent device 1 includes an anode 3, a hole injection layer 4, a hole transport layer 5, a light emitting layer 6, an electron transport layer 7, an electron injection layer 8, and a cathode 9 on a substrate 2. Have sequentially.
基板２は、透明または半透明の材料から形成されていることが好ましく、例えば、ガラス板、透明プラスチックシート、半透明プラスチックシート、石英、透明セラミックスあるいはこれらを組み合わせた複合シートがある。なお、基板２は、不透明な材料から形成されていてもよい。この場合は、基板２の反対側から光を取り出す素子構造とすればよい。さらに、基板２に、例えば、カラーフィルター膜、色変換膜、誘電体反射膜などを組み合わせることにより、発光色をコントロールしてもよい。基板２の膜厚は、特に限定されないが、０．１〜５０ｍｍ程度であるのが好ましく、０．１〜１０ｍｍであるのがより好ましい。 The substrate 2 is preferably formed of a transparent or translucent material, such as a glass plate, a transparent plastic sheet, a translucent plastic sheet, quartz, transparent ceramics, or a composite sheet combining these. The substrate 2 may be formed from an opaque material. In this case, an element structure in which light is extracted from the opposite side of the substrate 2 may be used. Furthermore, the emission color may be controlled by combining the substrate 2 with, for example, a color filter film, a color conversion film, a dielectric reflection film, or the like. Although the film thickness of the board | substrate 2 is not specifically limited, It is preferable that it is about 0.1-50 mm, and it is more preferable that it is 0.1-10 mm.
陽極３は、比較的仕事関数の大きい金属、合金または電気電導性化合物を電極物質として使用することが好ましい。陽極３に使用する電極物質としては、例えば、金、白金、銀、銅、コバルト、ニッケル、パラジウム、バナジウム、タングステン、酸化錫、酸化亜鉛、ＩＴＯ（インジウム・ティン・オキサイド）、ポリチオフェン、ポリピロールなどがある。これらの電極物質は、単独で使用してもよく、複数併用してもよい。陽極３は、これらの電極物質を、例えば、蒸着法、スパッタリング法などの気相成長法により、基板２の上に形成することができる。また、陽極３は、一層構造であっても、多層構造であってもよい。このような陽極３の膜厚は、特に限定されないが、１０〜５００ｎｍ程度であるのが好ましく、３０〜２００ｎｍ程度であるのがより好ましい。 The anode 3 preferably uses a metal, an alloy or an electrically conductive compound having a relatively large work function as an electrode material. Examples of the electrode material used for the anode 3 include gold, platinum, silver, copper, cobalt, nickel, palladium, vanadium, tungsten, tin oxide, zinc oxide, ITO (indium tin oxide), polythiophene, and polypyrrole. is there. These electrode materials may be used alone or in combination. The anode 3 can form these electrode materials on the substrate 2 by, for example, a vapor phase growth method such as a vapor deposition method or a sputtering method. The anode 3 may have a single layer structure or a multilayer structure. Although the film thickness of such an anode 3 is not specifically limited, It is preferable that it is about 10-500 nm, and it is more preferable that it is about 30-200 nm.
正孔注入層４は陽極３からの正孔の注入を容易にする機能、注入された正孔を輸送し、正孔輸送層５に注入する機能を含有する層である。本実施形態で用いる正孔注入層４は、アントラセン誘導体を含む層であり、より好ましくは電子アクセプターとアントラセン誘導体を含む混合層である。アントラセン誘導体は高い熱安定性や優れたキャリア輸送性を示す材料であり、通常は５．５ｅＶから６．０ｅＶの仕事関数を有する。このため、５．０ｅＶ前後の仕事関数を有する一般的な陽極３からの正孔注入は困難であるが、アントラセン誘導体に電子アクセプターをドーピングし、正のキャリアであるホールを強制的に発生させることで、陽極３とオーミックコンタクトが可能となり、陽極からの正孔注入が容易になる。混合層は、電子アクセプターとアントラセン誘導体がそれぞれ単独であっても、電子アクセプターもしくはアントラセン誘導体が２種類以上混合されたものでもよい。さらに、その他の物質を用いて、複数の材料の混合層であっても良い。混合層中のアントラセン誘導体の割合は通常は主成分であり、体積換算で５０％以上であるが、ホール注入に関して主体的役割を果たす場合は第２成分以下であってもよく、体積換算で１０％から５０％であってもよい。正孔注入層４の膜厚は、特に限定されないが、５〜１５０ｎｍ程度であるのが好ましく、１０〜８０ｎｍ程度であるのがより好ましい。 The hole injection layer 4 is a layer containing a function of facilitating injection of holes from the anode 3 and a function of transporting the injected holes and injecting them into the hole transport layer 5. The hole injection layer 4 used in this embodiment is a layer containing an anthracene derivative, and more preferably a mixed layer containing an electron acceptor and an anthracene derivative. Anthracene derivatives are materials exhibiting high thermal stability and excellent carrier transport properties, and usually have a work function of 5.5 eV to 6.0 eV. For this reason, although it is difficult to inject holes from a general anode 3 having a work function of around 5.0 eV, an electron acceptor is doped into an anthracene derivative to forcibly generate holes that are positive carriers. Thus, ohmic contact with the anode 3 is possible, and hole injection from the anode is facilitated. The mixed layer may be a single electron acceptor and an anthracene derivative, or a mixture of two or more electron acceptors or anthracene derivatives. Furthermore, a mixed layer of a plurality of materials may be used using other substances. The ratio of the anthracene derivative in the mixed layer is usually the main component and is 50% or more in terms of volume. However, in the case where it plays a main role with respect to hole injection, it may be the second component or less. % To 50%. The film thickness of the hole injection layer 4 is not particularly limited, but is preferably about 5 to 150 nm, and more preferably about 10 to 80 nm.
正孔注入層４に用いられるアントラセン誘導体としては、特に限定されることは無いが、カルバゾールやジベンゾフラン等の極性基を置換基に有するアントラセン誘導体が陽極への密着性の観点から好ましく用いることができる。カルバゾールやジベンゾフランは、他に、全ての置換基が炭化水素化合物により形成されるアントラセン誘導体も好ましく用いることができる。 Although it does not specifically limit as an anthracene derivative used for the positive hole injection layer 4, The anthracene derivative which has polar groups, such as carbazole and dibenzofuran, as a substituent can be used preferably from a viewpoint of the adhesiveness to an anode. . In addition to carbazole and dibenzofuran, anthracene derivatives in which all substituents are formed by hydrocarbon compounds can also be preferably used.
以下に、カルバゾールやジベンゾフランを置換基に有するアントラセン誘導体の具体例を示すが、これらに限定されるものではない。
電子アクセプターとしては、酸化バナジウム、酸化ニオブ、酸化タンタル、酸化クロム、酸化ルテニウム、酸化レニウム、酸化タングステン、酸化亜鉛、酸化錫、酸化鉄、酸化モリブデンなどの無機化合物の他、ヘキサシアノアザトリフェニレンやその誘導体のような有機物を用いることもできるが、電子アクセプターとしての能力が高く、アントラセン誘導体と共蒸着によって成膜することのできる酸化バナジウム、酸化タングステン、酸化モリブデンが最良である。 Electron acceptors include vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, ruthenium oxide, rhenium oxide, tungsten oxide, zinc oxide, tin oxide, iron oxide, molybdenum oxide, and other inorganic compounds, as well as hexacyanoazatriphenylene and its derivatives. However, vanadium oxide, tungsten oxide, and molybdenum oxide, which have a high ability as an electron acceptor and can be formed by co-evaporation with an anthracene derivative, are the best.
正孔輸送層５は正孔注入層４から注入された正孔を発光層６へ注入する機能を有する層である。また、正孔注入層４に電子アクセプターが含まれる場合は、発光層６と接触することで、励起子を消光してしまうため、正孔注入層４と発光層６を接触させない緩衝層としての機能も果たしている。本実施形態ではアントラセン誘導体を用いる。 The hole transport layer 5 is a layer having a function of injecting holes injected from the hole injection layer 4 into the light emitting layer 6. In addition, when the hole injection layer 4 contains an electron acceptor, the exciton is quenched by contact with the light emitting layer 6, so that the hole injection layer 4 and the light emitting layer 6 are not brought into contact with each other. It also plays a function. In this embodiment, an anthracene derivative is used.
正孔輸送層５に用いられるアントラセン誘導体としては、特に限定されることは無いが、キャリアの輸送性に優れた、全ての置換基が炭化水素化合物により形成されるアントラセン誘導体が好ましい。 The anthracene derivative used for the hole transport layer 5 is not particularly limited, but an anthracene derivative excellent in carrier transportability and in which all substituents are formed of a hydrocarbon compound is preferable.
発光層６は、注入された正孔および電子の輸送機能、正孔と電子の再結合により励起子を生成させる機能を有する化合物を含有する層であり、キャリアの輸送や薄膜構造体としての機能を有するホスト材料と、発光の機能を有する発光ドーパントを含んでいる。本実施形態では、ホスト材料にはアントラセン誘導体を用いる。 The light emitting layer 6 is a layer containing a compound having a function of transporting injected holes and electrons, and a function of generating excitons by recombination of holes and electrons, and functions as carrier transport and a thin film structure. And a light-emitting dopant having a light-emitting function. In this embodiment, an anthracene derivative is used as the host material.
発光層６にホスト材料として用いられるアントラセン誘導体としては、特に限定されることは無いが、正孔輸送性、電子輸送性の何れにも優れ、高い蛍光量子効率を示すなどの理由で、全ての置換基が炭化水素化合物により形成されるアントラセン誘導体が好ましい。発光層６中のアントラセン誘導体の割合は、ホスト材料であることから通常は主成分であり、体積換算で５０％以上であるが、キャリアの輸送や励起子の生成に主体的な役割を果たしている場合は第２成分以下であってもよく、体積換算で１０％から５０％であってもよい。 The anthracene derivative used as the host material for the light-emitting layer 6 is not particularly limited, but is excellent in both hole transporting properties and electron transporting properties, and exhibits high fluorescence quantum efficiency. Anthracene derivatives in which the substituent is formed by a hydrocarbon compound are preferred. The ratio of the anthracene derivative in the light emitting layer 6 is usually a main component because it is a host material, and is 50% or more in terms of volume, but plays a main role in carrier transport and exciton generation. In the case, it may be the second component or less, and may be 10% to 50% in terms of volume.
以下に、発光層６に用いることのできるアントラセン誘導体の具体例を示すが、これらに限定されるものではない。また、これらのアントラセン誘導体は正孔輸送層５、電子輸送層７にも好ましく用いられる他、正孔注入層４、電子注入層８に用いることもできる。
Although the specific example of the anthracene derivative which can be used for the light emitting layer 6 is shown below, it is not limited to these. Further, these anthracene derivatives are preferably used for the hole transport layer 5 and the electron transport layer 7, and can also be used for the hole injection layer 4 and the electron injection layer 8.
発光ドーパントは、正孔と電子の再結合により生成した励起子エネルギーにより発光する化合物である。高い発光量子収率を有する材料が好ましく、加えて正孔や電子をトラップする機能を有する材料がより好ましい。本実施形態では、通常の電界発光素子で用いられている発光ドーパントを用いることができ、具体的には、芳香族炭化水素、芳香族アミン化合物、スチリルアミン化合物、シアノ基を置換基に有する芳香族炭化水素化合物、キナクリドン、クマリン、ローダミンなどを用いることができる。 The luminescent dopant is a compound that emits light by exciton energy generated by recombination of holes and electrons. A material having a high emission quantum yield is preferable, and a material having a function of trapping holes and electrons is more preferable. In the present embodiment, a light emitting dopant used in a normal electroluminescent device can be used. Specifically, an aromatic hydrocarbon, an aromatic amine compound, a styrylamine compound, an aromatic having a cyano group as a substituent. Group hydrocarbon compounds, quinacridone, coumarin, rhodamine and the like can be used.
本実施形態の電界発光素子では、正孔輸送層５と発光層６との界面、あるいは発光層６と電子輸送層７との界面に注入障壁が無いため、発光ドーパントには通常よりも強力なキャリアトラップ性が必要となる。このような発光ドーパントとしては、正孔トラップ性ドーパントであれば、１分子に２個以上のトリアリールアミン構造を有する芳香族アミン化合物、あるいは電子トラップ性ドーパントであれば、シアノ基を置換基に有する芳香族炭化水素化合物などがより好ましい。 In the electroluminescent element of this embodiment, since there is no injection barrier at the interface between the hole transport layer 5 and the light emitting layer 6 or the interface between the light emitting layer 6 and the electron transport layer 7, the light emitting dopant is stronger than usual. Carrier trapping is required. As such a light-emitting dopant, if it is a hole trapping dopant, an aromatic amine compound having two or more triarylamine structures per molecule, or if it is an electron trapping dopant, a cyano group is used as a substituent. An aromatic hydrocarbon compound or the like is more preferable.
シアノ基を置換基に有する芳香族炭化水素化合物としては下記構造の一般式（I）で示される化合物が特に好ましい。
（一般式（Ｉ）におけるＡは多環芳香族化合物である。Ｌは多環芳香族化合物とシアノ基を結ぶ連結基であり、置換または無置換のアリール基、置換または無置換の複素環基を示す。ｍ、ｎ、ｘは価数を表し、１〜１０の何れかの整数である。）
As the aromatic hydrocarbon compound having a cyano group as a substituent, a compound represented by the general formula (I) having the following structure is particularly preferable.
(A in the general formula (I) is a polycyclic aromatic compound. L is a linking group connecting the polycyclic aromatic compound and the cyano group, and is a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group. M, n, and x represent a valence and are any integer of 1 to 10.)
Ａで表される多環芳香族化合物は、特に限定されることは無いがフルオランテン誘導体が好ましく、特にベンゾフルオランテンが好ましい。この場合、価数ｍは１または２であることが好ましい。Ｌは連結基であり、通常はフェニレン基、ナフチレン基等の低分子量の炭化水素化合物である。価数Ｘは連結基の数を表し、通常は１から３である。価数ｎは連結基Ｌ上のシアノ基の数を表し、通常は１から５である。 The polycyclic aromatic compound represented by A is not particularly limited, but a fluoranthene derivative is preferable, and benzofluoranthene is particularly preferable. In this case, the valence m is preferably 1 or 2. L is a linking group and is usually a low molecular weight hydrocarbon compound such as a phenylene group or a naphthylene group. The valence X represents the number of linking groups and is usually 1 to 3. The valence n represents the number of cyano groups on the linking group L, and is usually 1 to 5.
以下に一般式（I）の具体例を示すが、これらに限定されるものではない。
発光ドーパントのホスト化合物に対する含有量は通常０．０１〜２０ｗｔ％であり、さらには０．１〜１５ｗｔ％であることが好ましい。 The content of the luminescent dopant with respect to the host compound is usually 0.01 to 20 wt%, and more preferably 0.1 to 15 wt%.
発光層６には、さらにその他の化合物を含有させても良い。キャリア輸送材料を混ぜることで発光層のキャリア輸送性を調節できる他、蛍光色素を混ぜることで発光色を変換して使用することができる。このような化合物としては、例えば、キナクリドン、ルブレン、スチリル系色素などの色素化合物、トリアリールアミン誘導体などのキャリア輸送性化合物が挙げられる。 The light emitting layer 6 may further contain other compounds. In addition to adjusting the carrier transport property of the light emitting layer by mixing a carrier transporting material, the light emitting color can be converted and used by mixing a fluorescent dye. Examples of such compounds include dye compounds such as quinacridone, rubrene, and styryl dyes, and carrier transporting compounds such as triarylamine derivatives.
発光層６の膜厚は、特に限定されないが、０．１〜１００ｎｍ程度が好ましく、１〜５０ｎｍ程度がより好ましい。 Although the film thickness of the light emitting layer 6 is not specifically limited, About 0.1-100 nm is preferable and about 1-50 nm is more preferable.
電子輸送層７は、電子注入層８から注入された電子を発光層６に輸送する機能を有する層である。本実施形態では、アントラセン誘導体を用いる。アントラセン誘導体の具体例は、Ｂ−１〜Ｂ−１１に示したものを用いることができるが、これらに限定されるものではない。 The electron transport layer 7 is a layer having a function of transporting electrons injected from the electron injection layer 8 to the light emitting layer 6. In this embodiment, an anthracene derivative is used. Specific examples of the anthracene derivative may be those shown in B-1 to B-11, but are not limited thereto.
電子輸送層７の膜厚は、特に限定されないが、０．１〜２００ｎｍ程度であるのが好ましく、１〜１００ｎｍ程度がより好ましい。 Although the film thickness of the electron carrying layer 7 is not specifically limited, About 0.1-200 nm is preferable and about 1-100 nm is more preferable.
電子注入層８は、陰極９からの電子の注入を容易にする機能の他、陰極９との密着性を高める機能を有するものである。本実施形態では、アントラセン誘導体を用いる。 The electron injection layer 8 has a function of facilitating injection of electrons from the cathode 9 and a function of improving adhesion with the cathode 9. In this embodiment, an anthracene derivative is used.
電子注入層８に用いられるアントラセン誘導体としては、特に限定されることは無いが、ピリジンやピリミジン、キノキサリン、イミダゾピリジン、イミダゾピリミジン、オキサジアゾール、フェナントロリン等の含窒素複素環を置換基に有するアントラセン誘導体が好ましい。これらのアントラセン誘導体は、陰極への密着性が良好である他、陰極からの電子注入性が優れている材料である。他に、全ての置換基が炭化水素化合物により形成されるアントラセン誘導体も好ましく用いることができる。 The anthracene derivative used for the electron injection layer 8 is not particularly limited, but anthracene having a nitrogen-containing heterocyclic ring such as pyridine, pyrimidine, quinoxaline, imidazopyridine, imidazopyrimidine, oxadiazole, phenanthroline as a substituent. Derivatives are preferred. These anthracene derivatives are materials having excellent adhesion to the cathode and excellent electron injection from the cathode. In addition, anthracene derivatives in which all substituents are formed by hydrocarbon compounds can also be preferably used.
以下に、含窒素複素環を置換基に有するアントラセン誘導体の具体例を示すが、これらに限定されるものではない。
電子注入層８に用いられるアントラセン誘導体には、電子ドナーとして機能する化合物をドーピングして用いても良い。アントラセン誘導体に電子ドナーをドーピングし、負のキャリアを強制的に発生させることで、陰極とオーミックコンタクトが可能となり、陰極からの電子注入をより容易にすることができる。このような電子ドナーしては、リチウム、ナトリウム、カリウムなどのアルカリ金属およびその酸化物やハロゲン化物、カルシウム、マグネシウムなどのアルカリ土類金属およびその酸化物やハロゲン化物などを用いることができる。 The anthracene derivative used for the electron injection layer 8 may be doped with a compound that functions as an electron donor. By doping an anthracene derivative with an electron donor and forcibly generating negative carriers, ohmic contact with the cathode becomes possible, and electron injection from the cathode can be facilitated. As such an electron donor, alkali metals such as lithium, sodium, and potassium and oxides and halides thereof, alkaline earth metals such as calcium and magnesium, oxides and halides thereof, and the like can be used.
電子注入層８の膜厚は、特に限定されないが、０．０１〜１００ｎｍ程度であるのが好ましく、０．０１〜１０ｎｍ程度がより好ましい。 The thickness of the electron injection layer 8 is not particularly limited, but is preferably about 0.01 to 100 nm, and more preferably about 0.01 to 10 nm.
陰極９は、比較的仕事関数の小さい金属およびその塩、合金、または電気電導性化合物を電極構成物質として使用することができる。例えば、金属として、リチウム、ナトリウム、カルシウム、マグネシウム、インジウム、ルテニウム、チタニウム、マンガン、イットリウム、アルミニウム、酸化物として酸化リチウム、酸化ナトリウム、酸化カルシウム、酸化マグネシウム、弗化物として、弗化リチウム、弗化ナトリウム、弗化カルシウム、弗化マグネシウム、合金として、リチウム−インジウム合金、ナトリウム−カリウム合金、マグネシウム−銀合金、マグネシウム−インジウム合金、アルミニウム−リチウム合金、アルミニウム−カルシウム合金、アルミニウム−マグネシウム合金、電気電導性化合物としてグラファイト薄膜などを挙げることができる。 For the cathode 9, a metal having a relatively small work function and a salt thereof, an alloy, or an electrically conductive compound can be used as an electrode constituent material. For example, lithium, sodium, calcium, magnesium, indium, ruthenium, titanium, manganese, yttrium, aluminum as metal, lithium oxide, sodium oxide, calcium oxide, magnesium oxide as oxide, lithium fluoride, fluoride as fluoride Sodium, calcium fluoride, magnesium fluoride, alloys include lithium-indium alloy, sodium-potassium alloy, magnesium-silver alloy, magnesium-indium alloy, aluminum-lithium alloy, aluminum-calcium alloy, aluminum-magnesium alloy, electrical conduction Examples of the functional compound include a graphite thin film.
これらの電極構成物質は、単独で使用してもよく、あるいは複数併用してもよい。陰極９は、これらの電極物質を、例えば、蒸着法、スパッタリング法、イオン化蒸着法、イオンプレーティング法、クラスターイオンビーム法などの方法により、電子注入層８の上に形成することができる。また、陰極９は一層構造であっても、多層構造であってもよい。なお、電界発光素子の発光を効率よく取り出すために、陽極３または陰極９の少なくとも一方の電極が、透明ないし半透明であることが好ましく、一般に、４００ｎｍから８００ｎｍまでの可視光波長領域での光の透過率が８０％以上となるように陽極３または陰極９の材料、厚みを設定することがより好ましい。 These electrode constituent materials may be used alone or in combination. The cathode 9 can be formed of these electrode materials on the electron injection layer 8 by a method such as vapor deposition, sputtering, ionized vapor deposition, ion plating, or cluster ion beam. The cathode 9 may have a single layer structure or a multilayer structure. In order to efficiently extract light emitted from the electroluminescent element, it is preferable that at least one of the anode 3 and the cathode 9 is transparent or translucent. Generally, light in a visible light wavelength region from 400 nm to 800 nm is used. More preferably, the material and thickness of the anode 3 or the cathode 9 are set so that the transmittance is 80% or more.
陰極９の厚さは、電極としての機能を十分に果たせる程度に低抵抗となる厚みが必要である。特に限定されないが、１０〜３０００ｎｍ程度であるのが好ましく、１０〜１０００ｎｍ程度がより好ましい。 The thickness of the cathode 9 needs to be low enough to sufficiently function as an electrode. Although not particularly limited, it is preferably about 10 to 3000 nm, and more preferably about 10 to 1000 nm.
以下、本発明の具体的な実施例を比較例とともに示し、本発明をさらに詳細に説明する。 Hereinafter, specific examples of the present invention will be shown together with comparative examples, and the present invention will be described in more detail.
（実施例１）
ガラス基板上にＲＦスパッタ法で、ＩＴＯ透明電極薄膜を１００ｎｍの厚さに成膜し、パターニングした。このＩＴＯ透明電極付きガラス基板を、中性洗剤、アセトン、エタノールを用いて超音波洗浄し、煮沸エタノール中から引き上げて乾燥した。透明電極表面をＵＶ／Ｏ３洗浄した後、真空蒸着装置の基板ホルダーに固定して、槽内を１×１０−４Ｐａ以下まで減圧した
Example 1
An ITO transparent electrode thin film having a thickness of 100 nm was formed on a glass substrate by RF sputtering and patterned. This glass substrate with an ITO transparent electrode was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol, and then pulled up from boiling ethanol and dried. After the surface of the transparent electrode was washed with UV / O 3, it was fixed to a substrate holder of a vacuum evaporation apparatus, and the inside of the tank was depressurized to 1 × 10 −4 Pa or less.
次に、真空蒸着装置のホルダーに基板を固定して、槽内を１×１０−４Ｐａ以下まで減圧した。減圧状態を保ったまま、例示化合物Ａ−３と、電子アクセプターとしての酸化モリブデンとを、体積比９５：５で、全体の蒸着速度０．１ｎｍ／ｓｅｃとして６０ｎｍの厚さに蒸着し、正孔注入層とした。 Next, the substrate was fixed to a holder of a vacuum vapor deposition apparatus, and the inside of the tank was depressurized to 1 × 10 −4 Pa or less. While maintaining the reduced pressure state, Exemplified Compound A-3 and molybdenum oxide as an electron acceptor were vapor-deposited at a volume ratio of 95: 5 to a thickness of 60 nm with an overall vapor deposition rate of 0.1 nm / sec. An injection layer was formed.
次に、減圧状態を保ったまま、例示化合物Ｂ−７のみを蒸着速度０．１ｎｍ／ｓｅｃで１０ｎｍの厚さに蒸着し、正孔輸送層とした。 Next, while maintaining the reduced pressure state, only Exemplified Compound B-7 was deposited to a thickness of 10 nm at a deposition rate of 0.1 nm / sec to form a hole transport layer.
さらに、減圧状態を保ったまま、ホスト材料として例示化合物Ｂ−７と、発光ドーパントとして例示化合物Ｃ−８を、発光ドーパントの含有量を３ｗｔ％で、全体の蒸着速度０．１ｎｍ／ｓｅｃとして４０ｎｍの厚さに共蒸着し、発光層とした。 Furthermore, while maintaining the reduced pressure state, the exemplified compound B-7 as the host material, the exemplified compound C-8 as the luminescent dopant, the content of the luminescent dopant is 3 wt%, and the overall deposition rate is 0.1 nm / sec, 40 nm. The light emitting layer was co-evaporated to a thickness of 1.
次に、減圧状態を保ったまま、電子輸送層として例示化合物Ｂ−７のみを２５ｎｍ、続けて電子注入層として例示化合物Ｄ−４を５ｎｍ、蒸着速度０．１ｎｍ／ｓｅｃで蒸着した。 Next, while maintaining the reduced pressure state, only Exemplified Compound B-7 was deposited as an electron transport layer at 25 nm, and subsequently Exemplified Compound D-4 was deposited as an electron injection layer at 5 nm at a deposition rate of 0.1 nm / sec.
次いで、ＬｉＦを蒸着速度０．１ｎｍ／ｓｅｃで１．２ｎｍの厚さに蒸着して電子注入電極とし、保護電極としてＡｌを１００ｎｍ蒸着し、最後にガラス封止して電界発光素子を得た。 Next, LiF was deposited to a thickness of 1.2 nm at a deposition rate of 0.1 nm / sec to form an electron injection electrode, Al was deposited to 100 nm as a protective electrode, and finally glass sealed to obtain an electroluminescent device.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２５００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は５．２６Ｖ、寿命時間は１２３０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. The electroluminescence device obtained blue light emission of 2500 cd / m 2 , the driving voltage was 5.26 V, and the lifetime was 1230 h.
（実施例２）
発光ドーパントを例示化合物Ｃ−８から下記構造の例示化合物Ｅ−１に変えた以外は、実施例１と同様にして電解発光素子を作成した。
(Example 2)
An electroluminescent device was produced in the same manner as in Example 1 except that the luminescent dopant was changed from the exemplified compound C-8 to the exemplified compound E-1 having the following structure.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２１００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は５．１３Ｖ、寿命時間は９００ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue light of 2100 cd / m 2 , the driving voltage was 5.13 V, and the lifetime was 900 h.
（実施例３）
ガラス基板上にＲＦスパッタ法で、ＩＴＯ透明電極薄膜を１００ｎｍの厚さに成膜し、パターニングした。このＩＴＯ透明電極付きガラス基板を、中性洗剤、アセトン、エタノールを用いて超音波洗浄し、煮沸エタノール中から引き上げて乾燥した。透明電極表面をＵＶ／Ｏ３洗浄した後、真空蒸着装置の基板ホルダーに固定して、槽内を１×１０−４Ｐａ以下まで減圧した
(Example 3)
An ITO transparent electrode thin film having a thickness of 100 nm was formed on a glass substrate by RF sputtering and patterned. This glass substrate with an ITO transparent electrode was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol, and then pulled up from boiling ethanol and dried. After the surface of the transparent electrode was washed with UV / O 3, it was fixed to a substrate holder of a vacuum evaporation apparatus, and the inside of the tank was depressurized to 1 × 10 −4 Pa or less.
次に、真空蒸着装置のホルダーに基板を固定して、槽内を１×１０−４Ｐａ以下まで減圧した。減圧状態を保ったまま、例示化合物Ｂ−７と、電子アクセプターとしての酸化モリブデンとを、体積比９５：５で、全体の蒸着速度０．１ｎｍ／ｓｅｃとして６０ｎｍの厚さに蒸着し、正孔注入層とした。 Next, the substrate was fixed to a holder of a vacuum vapor deposition apparatus, and the inside of the tank was depressurized to 1 × 10 −4 Pa or less. While maintaining the reduced pressure state, Exemplified Compound B-7 and molybdenum oxide as an electron acceptor were vapor-deposited at a volume ratio of 95: 5 to a thickness of 60 nm with an overall vapor deposition rate of 0.1 nm / sec. An injection layer was formed.
次に、減圧状態を保ったまま、例示化合物Ｂ−７のみを蒸着速度０．１ｎｍ／ｓｅｃで１０ｎｍの厚さに蒸着し、正孔輸送層とした。 Next, while maintaining the reduced pressure state, only Exemplified Compound B-7 was deposited to a thickness of 10 nm at a deposition rate of 0.1 nm / sec to form a hole transport layer.
さらに、減圧状態を保ったまま、ホスト材料として例示化合物Ｂ−７と、発光ドーパントとして例示化合物Ｃ−８を、発光ドーパントの含有量を３ｗｔ％で、全体の蒸着速度０．１ｎｍ／ｓｅｃとして４０ｎｍの厚さに共蒸着し、発光層とした。 Furthermore, while maintaining the reduced pressure state, the exemplified compound B-7 as the host material, the exemplified compound C-8 as the luminescent dopant, the content of the luminescent dopant is 3 wt%, and the overall deposition rate is 0.1 nm / sec, 40 nm. The light emitting layer was co-evaporated to a thickness of 1.
次に、減圧状態を保ったまま、電子輸送層として例示化合物Ｂ−７のみを２５ｎｍ、続けて電子注入層として例示化合物Ｄ−４を５ｎｍ、蒸着速度０．１ｎｍ／ｓｅｃで蒸着した。 Next, while maintaining the reduced pressure state, only Exemplified Compound B-7 was deposited as an electron transport layer at 25 nm, and subsequently Exemplified Compound D-4 was deposited as an electron injection layer at 5 nm at a deposition rate of 0.1 nm / sec.
次いで、ＬｉＦを蒸着速度０．１ｎｍ／ｓｅｃで１．２ｎｍの厚さに蒸着して電子注入電極とし、保護電極としてＡｌを１００ｎｍ蒸着し、最後にガラス封止して電界発光素子を得た。 Next, LiF was deposited to a thickness of 1.2 nm at a deposition rate of 0.1 nm / sec to form an electron injection electrode, Al was deposited to 100 nm as a protective electrode, and finally glass sealed to obtain an electroluminescent device.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２６００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は４．９７Ｖ、寿命時間１２７０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue light of 2600 cd / m 2 , the driving voltage was 4.97 V, and the lifetime was 1270 h.
（実施例４）
全ての例示化合物Ｂ−７を例示化合物Ｂ−４に変えた以外は実施例３と同様に電界発光素子を作成した。
Example 4
An electroluminescent device was produced in the same manner as in Example 3 except that all the exemplified compounds B-7 were changed to the exemplified compound B-4.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２７００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は５．０３Ｖ、寿命時間１３３０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue light of 2700 cd / m 2 , the driving voltage was 5.03 V, and the lifetime was 1330 h.
（実施例５）
発光ドーパントを例示化合物Ｃ−８から例示化合物Ｃ−９に変えた以外は、実施例３と同様にして電界発光素子を作成した。
(Example 5)
An electroluminescent device was produced in the same manner as in Example 3 except that the luminescent dopant was changed from Exemplified Compound C-8 to Exemplified Compound C-9.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは３２００ｃｄ／ｍ２の青緑色の発光が得られ、駆動電圧は４．８８Ｖ、寿命時間は１３７０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue-green light of 3200 cd / m 2 , the driving voltage was 4.88 V, and the lifetime was 1370 h.
（実施例６）
ガラス基板上にＲＦスパッタ法で、ＩＴＯ透明電極薄膜を１００ｎｍの厚さに成膜し、パターニングした。このＩＴＯ透明電極付きガラス基板を、中性洗剤、アセトン、エタノールを用いて超音波洗浄し、煮沸エタノール中から引き上げて乾燥した。透明電極表面をＵＶ／Ｏ３洗浄した後、真空蒸着装置の基板ホルダーに固定して、槽内を１×１０−４Ｐａ以下まで減圧した
(Example 6)
An ITO transparent electrode thin film having a thickness of 100 nm was formed on a glass substrate by RF sputtering and patterned. This glass substrate with an ITO transparent electrode was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol, and then pulled up from boiling ethanol and dried. After the surface of the transparent electrode was washed with UV / O 3, it was fixed to a substrate holder of a vacuum evaporation apparatus, and the inside of the tank was depressurized to 1 × 10 −4 Pa or less.
次に、真空蒸着装置のホルダーに基板を固定して、槽内を１×１０−４Ｐａ以下まで減圧した。減圧状態を保ったまま、例示化合物Ｂ−７と、電子アクセプターとしての酸化モリブデンとを、体積比９５：５で、全体の蒸着速度０．１ｎｍ／ｓｅｃとして６０ｎｍの厚さに蒸着し、正孔注入層とした。 Next, the substrate was fixed to a holder of a vacuum vapor deposition apparatus, and the inside of the tank was depressurized to 1 × 10 −4 Pa or less. While maintaining the reduced pressure state, Exemplified Compound B-7 and molybdenum oxide as an electron acceptor were vapor-deposited at a volume ratio of 95: 5 to a thickness of 60 nm with an overall vapor deposition rate of 0.1 nm / sec. An injection layer was formed.
次に、減圧状態を保ったまま、例示化合物Ｂ−７のみを蒸着速度０．１ｎｍ／ｓｅｃで１０ｎｍの厚さに蒸着し、正孔輸送層とした。 Next, while maintaining the reduced pressure state, only Exemplified Compound B-7 was deposited to a thickness of 10 nm at a deposition rate of 0.1 nm / sec to form a hole transport layer.
さらに、減圧状態を保ったまま、ホスト材料として例示化合物Ｂ−７と、発光ドーパントとして例示化合物Ｃ−８を、発光ドーパントの含有量を３ｗｔ％で、全体の蒸着速度０．１ｎｍ／ｓｅｃとして４０ｎｍの厚さに共蒸着し、発光層とした。 Furthermore, while maintaining the reduced pressure state, the exemplified compound B-7 as the host material, the exemplified compound C-8 as the luminescent dopant, the content of the luminescent dopant is 3 wt%, and the overall deposition rate is 0.1 nm / sec, 40 nm. The light emitting layer was co-evaporated to a thickness of 1.
次に、減圧状態を保ったまま、電子輸送層として例示化合物Ｂ−７のみを２５ｎｍ、続けて電子注入層として例示化合物Ｂ−７とＬｉ金属とを体積比９５：５で５ｎｍ、蒸着速度０．１ｎｍ／ｓｅｃで蒸着した。 Next, while maintaining the reduced pressure state, only Exemplified Compound B-7 was 25 nm as the electron transport layer, and subsequently Exemplified Compound B-7 and Li metal as the electron injection layer were 5 nm at a volume ratio of 95: 5, and the deposition rate was 0. Vapor deposition was performed at 1 nm / sec.
次いで、ＬｉＦを蒸着速度０．１ｎｍ／ｓｅｃで１．２ｎｍの厚さに蒸着して電子注入電極とし、保護電極としてＡｌを１００ｎｍ蒸着し、最後にガラス封止して電界発光素子を得た。 Next, LiF was deposited to a thickness of 1.2 nm at a deposition rate of 0.1 nm / sec to form an electron injection electrode, Al was deposited to 100 nm as a protective electrode, and finally glass sealed to obtain an electroluminescent device.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２５００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は４．８２Ｖ、寿命時間１１８０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue light of 2500 cd / m 2 , the driving voltage was 4.82 V, and the lifetime was 1180 h.
（実施例７）
電子注入層に、Ｌｉ金属に変えてＬｉＦを用いた以外は実施例６と同様に電界発光素子を作成した。
(Example 7)
An electroluminescent element was prepared in the same manner as in Example 6 except that LiF was used instead of Li metal for the electron injection layer.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２７００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は４．９５Ｖ、寿命時間１３２０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue light of 2700 cd / m 2 , the driving voltage was 4.95 V, and the lifetime was 1320 h.
（実施例８）
電子注入層におけるＢ−７をＤ−４に変えた以外は実施例６と同様に電界発光素子を作成した。
(Example 8)
An electroluminescent element was produced in the same manner as in Example 6 except that B-7 in the electron injection layer was changed to D-4.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２８００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は４．９９Ｖ、寿命時間１４１０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue light of 2800 cd / m 2 , the driving voltage was 4.99 V, and the lifetime was 1410 h.
（実施例９）
電子注入層におけるＢ−７をＤ−８に変えた以外は実施例６と同様に電界発光素子を作成した。
Example 9
An electroluminescent device was produced in the same manner as in Example 6 except that B-7 in the electron injection layer was changed to D-8.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２６００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は５．０８Ｖ、寿命時間１３５０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue light of 2600 cd / m 2 , the driving voltage was 5.08 V, and the lifetime was 1350 h.
（実施例１０）
全ての例示化合物Ｂ−７を例示化合物Ｂ−１１に変えた以外は実施例６と同様に電界発光素子を作成した。
(Example 10)
An electroluminescent device was produced in the same manner as in Example 6 except that all the exemplified compounds B-7 were changed to the exemplified compounds B-11.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２１００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は４．７２Ｖ、寿命時間１５７０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue light of 2100 cd / m 2 , the driving voltage was 4.72 V, and the lifetime was 1570 h.
（実施例１１）
正孔注入層における酸化モリブデンを酸化バナジウムに変えた以外は実施例３と同様に電界発光素子を作成した。
(Example 11)
An electroluminescent element was prepared in the same manner as in Example 3 except that the molybdenum oxide in the hole injection layer was changed to vanadium oxide.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２６００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は５．０８Ｖ、寿命時間１３５０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue light of 2600 cd / m 2 , the driving voltage was 5.08 V, and the lifetime was 1350 h.
（比較例１）
ガラス基板上にＲＦスパッタ法で、ＩＴＯ透明電極薄膜を１００ｎｍの厚さに成膜し、パターニングした。このＩＴＯ透明電極付きガラス基板を、中性洗剤、アセトン、エタノールを用いて超音波洗浄し、煮沸エタノール中から引き上げて乾燥した。透明電極表面をＵＶ／Ｏ３洗浄した後、真空蒸着装置の基板ホルダーに固定して、槽内を１×１０−４Ｐａ以下まで減圧した。
(Comparative Example 1)
An ITO transparent electrode thin film having a thickness of 100 nm was formed on a glass substrate by RF sputtering and patterned. This glass substrate with an ITO transparent electrode was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol, and then pulled up from boiling ethanol and dried. After the surface of the transparent electrode was washed with UV / O 3, it was fixed to a substrate holder of a vacuum deposition apparatus, and the inside of the tank was depressurized to 1 × 10 −4 Pa or less.
次に、減圧状態を保ったまま、下記の例示化合物Ｆ−１を蒸着速度０．１ｎｍ／ｓｅｃ で３０ｎｍの膜厚に蒸着し、正孔注入層とした。 Next, the following exemplary compound F-1 was vapor-deposited to a film thickness of 30 nm at a vapor deposition rate of 0.1 nm / sec while maintaining the reduced pressure state to form a hole injection layer.
次いで、下記構造の例示化合物Ｇ−１を蒸着速度０．１ｎｍ／ｓｅｃで１０ｎｍの厚さに蒸着し、正孔輸送層とした。 Then, exemplary compound G-1 having the following structure was deposited at a deposition rate of 0.1 nm / sec to a thickness of 10 nm to form a hole transport layer.
さらに、減圧状態を保ったまま、ホスト材料としての例示化合物Ｂ−７と、発光ドーパントとしての例示化合物Ｃ−８とを、体積比９７：３で、全体の蒸着速度０．１ｎｍ／ｓｅｃとして４０ｎｍの厚さに蒸着し、発光層とした。 Further, while maintaining the reduced pressure state, the exemplified compound B-7 as the host material and the exemplified compound C-8 as the luminescent dopant were mixed at a volume ratio of 97: 3 with an overall deposition rate of 0.1 nm / sec to 40 nm. A light emitting layer was formed by vapor deposition.
次に、減圧状態を保ったまま、電子輸送層として例示化合物Ｂ−７を２５ｎｍ、続けて電子注入層としてトリス（８−ヒドロキシキノリン）アルミニウム（Ａｌｑ３）を５ｎｍ、蒸着速度０．１ｎｍ／ｓｅｃで蒸着した。 Next, while maintaining the reduced pressure state, Exemplified Compound B-7 was 25 nm as the electron transport layer, and subsequently Tris (8-hydroxyquinoline) aluminum (Alq3) was 5 nm as the electron injection layer at a deposition rate of 0.1 nm / sec. Vapor deposited.
次いで、ＬｉＦを蒸着速度０．１ｎｍ／ｓｅｃで０．５ｎｍの厚さに蒸着して電子注入電極とし、保護電極としてＡｌを１００ｎｍ蒸着し、最後にガラス封止して電界発光素子を得た。 Next, LiF was deposited to a thickness of 0.5 nm at a deposition rate of 0.1 nm / sec to form an electron injection electrode, Al was deposited to 100 nm as a protective electrode, and finally glass sealed to obtain an electroluminescent device.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは１１００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は８．８７Ｖ、寿命時間４８０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. From this electroluminescent element, blue light emission of 1100 cd / m 2 was obtained, the driving voltage was 8.87 V, and the lifetime was 480 h.
（比較例２）
発光ドーパントを例示化合物Ｃ−８から例示化合物Ｅ−１に変えた以外は、比較例１と同様にして電解発光素子を作成した。
(Comparative Example 2)
An electroluminescent device was produced in the same manner as in Comparative Example 1 except that the luminescent dopant was changed from Exemplified Compound C-8 to Exemplified Compound E-1.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２５００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は９．２４Ｖ、寿命時間は８８０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue light of 2500 cd / m 2 , the driving voltage was 9.24 V, and the lifetime was 880 h.
（比較例３）
電子注入層として例示化合物Ｄ−４をトリス（８−ヒドロキシキノリン）アルミニウム（Ａｌｑ３）に変えた以外は実施例３と同様にして電解発光素子を作成した。
(Comparative Example 3)
An electroluminescent device was produced in the same manner as in Example 3 except that the exemplified compound D-4 was changed to tris (8-hydroxyquinoline) aluminum (Alq3) as the electron injection layer.
この電界発光素子に直流電流を印加し、電流密度５０ｍＡ／ｃｍ２の駆動条件で、輝度、電圧を測定した。さらに、同じ条件で駆動寿命の測定も行い、初期の輝度から半分の輝度になるまでの時間を寿命時間とした。この電界発光素子からは２３００ｃｄ／ｍ２の青色発光が得られ、駆動電圧は６．１９Ｖ、寿命時間１０５０ｈであった。 A direct current was applied to the electroluminescent element, and luminance and voltage were measured under a driving condition of a current density of 50 mA / cm 2 . Further, the drive life was measured under the same conditions, and the time from the initial brightness to half the brightness was defined as the life time. This electroluminescent element emitted blue light of 2300 cd / m 2 , the driving voltage was 6.19 V, and the lifetime was 1050 h.
以下に実施例および比較例の一覧を示す。
以上のように、本発明に係る電界発光素子は、正孔注入層から電子注入層に至るまでの全ての層にアントラセン誘導体を用いることで、正孔および電子の注入障壁を大幅に改善できる。その結果として、低電圧駆動で長寿命の電界発光素子を提供することができ、自動車のインパネなどの表示部、テレビや携帯電話などのディスプレイ、照明などに好適に使用できる。 As described above, the electroluminescent device according to the present invention can significantly improve the hole and electron injection barrier by using anthracene derivatives in all layers from the hole injection layer to the electron injection layer. As a result, it is possible to provide an electroluminescent element with a low voltage drive and a long life, and can be suitably used for a display unit such as an instrument panel of a car, a display such as a television or a mobile phone, and illumination.
１ 電界発光素子
２ 基板
３ 陽極
４ 正孔注入層
５ 正孔輸送層
６ 発光層
７ 電子輸送層
８ 電子注入層
９ 陰極
DESCRIPTION OF SYMBOLS 1 Electroluminescent element 2 Substrate 3 Anode 4 Hole injection layer 5 Hole transport layer 6 Light emitting layer 7 Electron transport layer 8 Electron injection layer 9 Cathode
Claims (5)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014082630A JP6369747B2 (en) | 2014-04-14 | 2014-04-14 | Electroluminescent device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014082630A JP6369747B2 (en) | 2014-04-14 | 2014-04-14 | Electroluminescent device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2015204357A JP2015204357A (en) | 2015-11-16 |
| JP6369747B2 true JP6369747B2 (en) | 2018-08-08 |
Family
ID=54597648
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2014082630A Expired - Fee Related JP6369747B2 (en) | 2014-04-14 | 2014-04-14 | Electroluminescent device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6369747B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11696495B2 (en) * | 2018-08-06 | 2023-07-04 | Lg Display Co., Ltd. | Organic emitting compound, and organic light emitting diode and organic light emitting display device including the same |
| JP7325731B2 (en) | 2018-08-23 | 2023-08-15 | 国立大学法人九州大学 | organic electroluminescence element |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101595080B (en) * | 2006-11-15 | 2013-12-18 | 出光兴产株式会社 | Fluoranthene compound, organic electroluminescent element using fluoranthene compound, and solution containing organic electroluminescent material |
| JP2009259994A (en) * | 2008-04-16 | 2009-11-05 | ▲いく▼▲らい▼光電科技股▲ふん▼有限公司 | Organic electroluminescent device utilizing anthracene compound |
| CN103258964B (en) * | 2008-05-16 | 2016-06-01 | 株式会社半导体能源研究所 | Luminous element, electronics and means of illumination |
-
2014
- 2014-04-14 JP JP2014082630A patent/JP6369747B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2015204357A (en) | 2015-11-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101408547B1 (en) | Organic electroluminescent element | |
| JP6187080B2 (en) | Electroluminescent device | |
| CN110492005B (en) | Organic electroluminescent device with exciplex as main material | |
| JPWO2004077889A1 (en) | Organic electroluminescence device | |
| JP2008053556A (en) | Organic electroluminescent element | |
| JP2020532883A (en) | Organic electroluminescent device | |
| WO2016133058A1 (en) | Electroluminescent element | |
| JP2007194241A (en) | Light emitting device | |
| JP2010027761A (en) | Light emitting element | |
| JP4915651B2 (en) | Organic electroluminescence device | |
| TW201114320A (en) | Organic electroluminescent element | |
| JP6369747B2 (en) | Electroluminescent device | |
| JP6323774B2 (en) | Electroluminescent device | |
| JP2015159238A (en) | Compound for organic electroluminescent element and organic electroluminescent element using the same | |
| CN111740020A (en) | Efficient and long-life blue light device | |
| JP2016183140A (en) | Compound for electroluminescence devices, and electroluminescence device prepared therewith | |
| JP2015109370A (en) | Electroluminescence device | |
| JP2008053558A (en) | Organic electroluminescent element | |
| JP2019169618A (en) | Organic electroluminescent element | |
| JP6532539B2 (en) | Organic light emitting device | |
| JP6770900B2 (en) | Organic electroluminescence element | |
| JP2016150920A (en) | Compound for organic electroluminescent element and organic electroluminescent element using the same | |
| JP6770899B2 (en) | Organic electroluminescence element | |
| JP6803727B2 (en) | Organic electroluminescence element | |
| JP2004253373A (en) | Organic el element |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20170124 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20171129 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20171129 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20180125 |
|
| 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: 20180626 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20180628 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 6369747 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| LAPS | Cancellation because of no payment of annual fees |