Patent Application
20230322831
This application claims priority to and the benefit of Korean Patent Application No. 10-2021-0152569, filed on Nov. 8, 2021, in the Korean Intellectual Property Office, the entire content of which is hereby incorporated by reference.
One or more embodiments of the present disclosure relate to a light-emitting device including an organometallic compound, an electronic apparatus including the light-emitting device, and the organometallic compound.
Light-emitting devices are self-emissive devices that have wide viewing angles, high contrast ratios, short response times, and excellent characteristics in terms of brightness, driving voltage, and response speed.
Light-emitting devices may include a first electrode on a substrate, and a hole transport region, an emission layer, an electron transport region, and a second electrode sequentially stacked on the first electrode. Holes provided from the first electrode may move toward the emission layer through the hole transport region, and electrons provided from the second electrode may move toward the emission layer through the electron transport region. Carriers, such as holes and electrons, recombine in the emission layer to produce excitons. These excitons transition from an excited state to a ground state to thereby generate light.
Provided are a light-emitting device including an organometallic compound, an electronic apparatus including the light-emitting device, and the organometallic compound.
Additional aspects of embodiments will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments of the disclosure.
According to one or more embodiments, provided is a light-emitting device including:
In Formulae 1-1 and 1-2,
According to one or more embodiments, an electronic apparatus including the light-emitting device is provided.
According to one or more embodiments, the organometallic compound represented by Formula 1-1 or 1-2 is provided.
The above and other aspects and features of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:
Reference will now be made in more detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects of embodiments of the present description. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Throughout the disclosure, the expression “at least one of a, b or c” indicates only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof.
A light-emitting device may include: a first electrode; a second electrode facing the first electrode; an interlayer between the first electrode and the second electrode and including an emission layer; and an organometallic compound represented by Formula 1-1 or 1-2:
wherein M in Formulae 1-1 and 1-2 may be platinum (Pt), palladium (Pd), copper(Cu), silver (Ag), gold (Au), rhodium (Rh), ruthenium (Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), or thulium (Tm).
In an embodiment, M may be platinum (Pt).
Ring CY1 to ring CY3 in Formulae 1-1 and 1-2 may each independently be a C5-C30 carbocyclic group or a C1-C30 heterocyclic group.
In an embodiment, ring CY1 to ring CY3 may each independently be a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a cyclopentadiene group, a 1,2,3,4-tetrahydronaphthalene group, a thiophene group, a furan group, an indole group, a benzoborole group, a benzophosphole group, an indene group, a benzosilole group, a benzogermole group, a benzothiophene group, a benzoselenophene group, a benzofuran group, a carbazole group, a dibenzoborole group, a dibenzophosphole group, a fluorene group, a dibenzosilole group, a dibenzogermole group, a dibenzothiophene group, a dibenzoselenophene group, a dibenzofuran group, a dibenzothiophene 5-oxide group, a 9H-fluorene-9-one group, a dibenzothiophene 5,5-dioxide group, an azaindole group, an azabenzoborole group, an azabenzophosphole group, an azaindene group, an azabenzosilole group, an azabenzogermole group, an azabenzothiophene group, an azabenzoselenophene group, an azabenzofuran group, an azacarbazole group, an azadibenzoborole group, an azadibenzophosphole group, an azafluorene group, an azadibenzosilole group, an azadibenzogermole group, an azadibenzothiophene group, an azadibenzoselenophene group, an azadibenzofuran group, an azadibenzothiophene 5-oxide group, an aza-9H-fluorene-9-one group, an azadibenzothiophene 5,5-dioxide group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrrole group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an iso-oxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, a benzothiadiazole group, a 5,6,7,8-tetrahydroisoquinoline group, or a 5,6,7,8-tetrahydroquinoline group.
In an embodiment, ring CY1 may be a benzene group, a naphthalene group, or a pyridine group.
In an embodiment, ring CY2 and ring CY3 may each independently be a C1-C30 heterocyclic group.
In an embodiment, ring CY2 and ring CY3 may include at least one nitrogen.
In an embodiment, ring CY2 may be an indole group or a carbazole group.
In an embodiment, ring CY3 may be a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrrole group, a pyrazole group, an imidazole group, a triazole group, a benzopyrazole group, a benzimidazole group, or a benzothiazole group.
In an embodiment, a group represented by
in Formulae 1-1 and 12 may be any one of groups represented by Formulae CY1 (1) to CY1(20):
wherein, in Formulae CY1(1) to CY1(20),
In an embodiment, R11 to R13 may each independently be:
In an embodiment, a group represented by
in Formulae 1-1 and 1-2 may be any one of groups represented by Formulae CY2(1) to CY2(11):
In an embodiment, a group represented by Formula CY2(1) may be any one of groups represented by Formulae CY2(1)-1 to CY2(1)-7:
wherein, in Formulae CY2(1)-1 to CY2(1)-7,
In an embodiment, R21 to R23 may each independently be:
In an embodiment, a group represented by
in Formula 1-1 may be any one of groups represented by Formulae CY3(1) to CY3(14):
In an embodiment, R31 to R33 may each independently be:
X1 to X3 in Formulae 1-1 and 1-2 may each independently be C or N.
In an embodiment, X1 and X2 may each be C, and X3 may be N.
X21 in Formula 1-1 and X21 in Formula 1-2 may each be C.
In Formulae 1-1 and 1-2,
In an embodiment, in Formulae 1-1 and 1-2,
in Formulae 1-1 and 1-2 indicates a single bond or a double bond.
A group represented by
in Formulae 1-1 and 1-2 may be any one of groups represented by Formulae CYN(1) to CYN(21):
In an embodiment, Z11 to Z16 may each independently be deuterium, —F, —Cl, —Br, —I, a cyano group, a C1-C60 alkyl group unsubstituted or substituted with at least one R10a, a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a, or —Si(Q1)(Q2)(Q3).
In an embodiment, Z11 to Z16 may each independently be:
In an embodiment, Y11 to Y14 may each be C.
In an embodiment,
In an embodiment, Y11 and Y14 may each be N, and Y12 and Y13 may each be C.
In an embodiment, Y15 to Y18 may each be C.
In an embodiment,
In an embodiment, Y15 and Y18 may each be N, and Y16 and Y17 may each be C.
L1 to L3 in Formulae 1-1 and 1-2 may each independently be a single bond,
In an embodiment, L1 and L3 may each be a single bond.
In an embodiment, L2 may be *—O—*’.
n1 to n3 in Formulae 1-1 and 1-2 may each independently be an integer from 1 to 5.
In an embodiment, n2 may be 1.
R1 to R3, Z1 to Z8, R1a and R1b in Formulae 1-1 and 1-2 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C1-C60 alkyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkenyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkynyl group unsubstituted or substituted with at least one R10a, a C1-C60 alkoxy group unsubstituted or substituted with at least one R10a, a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a, a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a, a C6-C60 aryloxy group unsubstituted or substituted with at least one R10a, a C6-C60 arylthio group unsubstituted or substituted with at least one R10a, —C(Q1)(Q2)(Q3), —Si(Q1)(Q2)(Q3), —N(Q1)(Q2), —B(Q1)(Q2), —C(═O)(Q1), —S(═O)2(Q1), or —P(═O)(Q1)(Q2).
In an embodiment, R1 to R3, Z1 to Z8, R1a and R1b may each independently be:
In an embodiment, R1 to R3, Z1 to Z8, R1a and R1b may each independently be:
In an embodiment, R1 to R3 may each independently be:
In an embodiment,
Z1 to Z8 may each independently be:
In an embodiment, a C3-C60 carbocyclic group and a C1-C60 heterocyclic group, which are formed by bonding Z1 and Z2, Z3 and Z4, Z5 and Z6, or Z7 and Z8 together, may include a 6-membered ring.
In an embodiment,
In an embodiment, the organometallic compound represented by Formula 1-1 or 1-2 may be any one of Compounds 1 to 80.
The organometallic compound represented by Formula 1-1 or 1-2 includes a group represented by Formula 1A or 1B among Formulae 1-1 and 1-2.
According to embodiments of the present disclosure, the organometallic compound represented by Formula 1-1 or 1-2 may have improved rigidity of ligands, and thus, exhibit relatively excellent triplet metal to ligand charge transfer (3MLCT) characteristics. Therefore, an electronic device (for example, an organic light-emitting device) having high efficiency and long lifespan may be implemented by using the organometallic compound.
In an embodiment, the organometallic compound represented by Formula 1-1 or 1-2 may have a 3MLCT value of about 10% or more.
Methods of synthesizing the organometallic compound represented by Formula 1-1 or 1-2 may be easily understood to those of ordinary skill in the art by referring to Synthesis Examples and/or Examples described herein.
In an embodiment,
In an embodiment, the interlayer of the light-emitting device may include the organometallic compound represented by Formula 1.
In an embodiment, the emission layer of the light-emitting device may include the organometallic compound represented by Formula 1.
In an embodiment, the emission layer may emit blue light. In an embodiment, the emission layer may emit blue light having a maximum emission wavelength of 410 nm to 500 nm, 410 nm to 480 nm, 420 nm to 480 nm, or 430 nm to 470 nm.
In an embodiment, the emission layer of the light-emitting device may include a dopant and a host, and the dopant may include the organometallic compound represented by Formula 1-1 or 1-2. For example, the organometallic compound may serve as a dopant. The emission layer may emit, for example, blue light. The blue light may have a maximum emission wavelength in a range of, for example, about 430 nm to about 470 nm.
In an embodiment, the electron transport region of the light-emitting device may include a hole blocking layer, and the hole blocking layer may include a phosphine oxide-containing compound, a silicon-containing compound, or any combination thereof. In an embodiment, the hole blocking layer may directly contact the emission layer.
In an embodiment, the interlayer in the light-emitting device may include i) a first compound, which is the organometallic compound represented by Formula 1-1 or 1-2; and ii) a second compound including at least one TT electron-deficient nitrogen-containing C1-C60 cyclic group, a third compound including a group represented by Formula 3, a fourth compound capable of emitting delayed fluorescence, or any combination thereof, and the first compound, the second compound, the third compound, and the fourth compound are different from each other:
The second compound may include a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, or any combination thereof.
In an embodiment, the light-emitting device may further include at least one of the second compound and the third compound, in addition to the first compound.
In an embodiment, the light-emitting device may further include the fourth compound, in addition to the first compound.
In an embodiment, the light-emitting device may include the first compound, the second compound, the third compound, and the fourth compound.
In an embodiment, the interlayer may include the second compound. The interlayer may further include, in addition to the first compound and the second compound, the third compound, the fourth compound, or any combination thereof.
In an embodiment, a difference between the triplet energy level (eV) of the fourth compound and the singlet energy level (eV) of the fourth compound may be about 0 eV or higher and 0.5 eV or lower (or, about 0 eV or higher and about 0.3 eV or lower).
In an embodiment, the fourth compound may be a compound including at least one cyclic group including boron (B) and nitrogen (N) as ring-forming atoms.
In an embodiment, the fourth compound may be a C8-C60 polycyclic group-containing compound including at least two condensed cyclic groups (e.g., at least one first ring and at least one second ring) that share a boron atom (B).
In an embodiment, the fourth compound may include a condensed ring in which at least one third ring may be condensed together with at least one fourth ring,
In an embodiment, the interlayer may include the fourth compound. The interlayer may include, in addition to the first compound and the fourth compound, the second compound, the third compound, or any combination thereof.
In an embodiment, the interlayer may include the third compound. In an embodiment, the third compound may not include CBP described herein and a compound represented by mCBP.
The emission layer in the interlayer may include i) the first compound; and ii) the second compound, the third compound, the fourth compound, or any combination thereof.
The emission layer may emit phosphorescence or fluorescence emitted from the first compound. In an embodiment, phosphorescence or fluorescence emitted from the first compound may be blue light.
In an embodiment, the emission layer in the light-emitting device may include the first compound and the second compound, and the first compound and the second compound may form an exciplex.
In an embodiment, the emission layer in the light-emitting device may include the first compound, the second compound, and the third compound, and the second compound and the third compound may form an exciplex.
In an embodiment, the emission layer in the light-emitting device may include the first compound and the fourth compound, and the fourth compound may serve to improve color purity, luminescence efficiency, and/or lifespan characteristics of the light-emitting device.
When at least one compound (for example, the fourth compound) including boron (B) and nitrogen (N) as ring-forming atoms and the organometallic compound represented by Formula 1-1 or 1-2 are included together in a dopant, the organometallic compound represented by Formula 1-1 or 1-2 may serve as a sensitizer. When the organometallic compound represented by Formula 1-1 or 1-2 serves as a sensitizer, energy of excitons generated in the emission layer may be transferred to the organometallic compound, the energy may be transferred from the organometallic compound to another remaining dopant (for example, the fourth compound), and the other remaining dopant may serve as an emitter.
In an embodiment, the second compound may include a compound represented by Formula 2:
wherein, in Formula 2,
In an embodiment, the third compound may include a compound represented by Formula 3-1, a compound represented by Formula 3-2, a compound represented by Formula 3-3, a compound represented by Formula 3-4, a compound represented by Formula 3-5, or any combination thereof:
In an embodiment, the fourth compound may be a compound represented by Formula 502, a compound represented by Formula 503, or any combination thereof:
wherein, in Formulae 502 and 503,
b
61 to b63 in Formula 2 may respectively indicate the numbers of L61(s) to L63(S), and b61 to b63 may each be an integer from 1 to 5. When b61 is 2 or greater, at least two L61 (s) may be identical to or different from each other, when b62 is 2 or greater, at least two L62(S) may be identical to or different from each other, and when b63 is 2 or greater, at least two L63(S) may be identical to or different from each other. In an embodiment, b61 to b63 may each independently be 1 or 2.
L61 to L63 in Formula 2 may each independently be:
In an embodiment, in Formula 2, a bond between L51 and R51, a bond between L52 and R52, a bond between L53 and R53, a bond between at least two L51(s), a bond between at least two L52(s), a bond between at least two L53(s), a bond between L51 and a carbon atom between X54 and X55 in Formula 2, a bond between L52 and a carbon atom between X54 and X56 in Formula 2, and a bond between L53 and a carbon atom between X55 and X56 in Formula 2 may each be a “carbon-carbon single bond”.
In Formula 2, X64 may be N or C(R64), X65 may be N or C(R65), X66 may be N or C(R66), at least one of X64 to X66 may be N. R64 to R66 may respectively be the same as those described in the present specification. In an embodiment, two or three of X64 to X66 may each be N.
R61 to R66, R71 to R74, R81 to R85, R82a, R82b, R83a, R83b, R84a and R84b, R500a, R500b, R501 to R508, R505a, R505b, R506a, R506b, R507a, R507b, R508a, and R508b may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C1-C60 alkyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkenyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkynyl group unsubstituted or substituted with at least one R10a, a C1-C60 alkoxy group unsubstituted or substituted with at least one R10a, a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a, a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a, a C6-C60 aryloxy group unsubstituted or substituted with at least one R10a, a C6-C60 arylthio group unsubstituted or substituted with at least one R10a, —C(Q1)(Q2)(Q3), —Si(Q1)(Q2)(Q3), —N(Q1)(Q2), —B(Q1)(Q2), —C(═O)(Q1), —S(═O)2(Q1), or —P(═O)(Q1)(Q2). Q1 to Q3 are respectively the same as those described in the present specification.
In an embodiment, i) R1 to R5, Z11, Z12, Z21, and Z22 in Formula 1, ii) R11, R12, R21, R22, R31 to R34, R41 to R45, R5a, R5b, R51, and R52 in Formulae A1(1) to A1 (32), A1-1 to A1-4, A2-1 to A2-8, A3-1 to A3-15, A4-1 to A4-32, CY1(a), CY1-1, and CY1-2, iii) R51 to R56, R71 to R74, R81 to R85, R82a, R82b, R83a, R83b, R84a and R84b, R500a, R500b, R501 to R508, R505a, R505b, R506a, R506b, R507a, R507b, R508a, and R508b in Formulae 2, 3-1 to 3-5, 502, and 503, and iv) R10a may each independently be:
In an embodiment, in Formula 91,
In an embodiment, i) R1 to R5, Z11, Z12, Z21, and Z22 in Formula 1, ii) R11, R12, R21, R22, R31 to R34, R41 to R45, R5a, R5b, R51, and R52 in Formulae A1(1) to A1 (32), A1-1 to A1-4, A2-1 to A2-8, A3-1 to A3-15, A4-1 to A4-32, CY1(a), CY1-1, and CY1-2, iii) R51 to R56, R71 to R74, R81 to R85, R82a, R82b, R83a, R83b, R84a and R84b, R500a, R500b, R501 to R508, R505a, R505b, R506a, R506b, R507a, R507b, R508a, and R508b in Formulae 2, 3-1 to 3-5, 502, and 503, and iv) R10a may each independently be:
In Formulae 3-1 to 3-5, 502, and 503, a71 to a74 and a501 to a504 may respectively indicate the number of R71(s) to R74(s) and R501(s) to R504(s), and a71 to a74 and a501 to a504 may each independently be an integer from 0 to 20. When a71 is 2 or greater, at least two R71(s) may be identical to or different from each other, when a72 is 2 or greater, at least two R72(s) may be identical to or different from each other, when a73 is 2 or greater, at least two R73(s) may be identical to or different from each other, when a74 is 2 or greater, may be identical to or different from each other R74(s) may be identical to or different from each other, when a501 is 2 or greater, at least two R501(s) may be identical to or different from each other, when a502 is 2 or greater, at least two R502(s) may be identical to or different from each other, when a503 is 2 or greater, at least two R503(s) may be identical to or different from each other, and when a504 is 2 or greater, at least two R504(s) may be identical to or different from each other. a71 to a74 and a501 to a504 may each independently be an integer from 0 to 8.
In some embodiments, in Formula 2, the group represented by *-(L61)b61-R61 and the group represented by *-(L62)b62-R62 may not be a phenyl group.
In some embodiments, in Formula 2, the group represented by *-(L61)b61-R61 may be identical to the group represented by *-(L62)b62-R62.
In one or more embodiments, in Formula 2, the group represented by *-(L61)b61-R61 and the group represented by *-(L62)b62-R62 may be different from each other.
In one or more embodiments, in Formula 2, b61 and b62 may each be 1, 2, or 3, L61 and L62 may each independently be a benzene group, a pyridine group, a pyrimidine group, a pyridazine group, a pyrazine group, or a triazine group unsubstituted or substituted with at least one R10a.
In some embodiments, in Formula 2, R61 and R62 may each independently be a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a, a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a, a C6-C60 aryloxy group unsubstituted or substituted with at least one R10a, a C6-C60 arylthio group unsubstituted or substituted with at least one R10a, —C(Q1)(Q2)(Q3), or —Si(Q1)(Q2)(Q3),
wherein Q1 to Q3 may each independently be a C3-C60 carbocyclic group or a C1-C60 heterocyclic group, each unsubstituted or substituted with deuterium, —F, a cyano group, a C1-C60 alkyl group, a C1-C60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.
In an embodiment,
In an embodiment,
R51a to R51e and R52a to R52e in Formulae CY51-1 to CY51-26 and Formulae CY52-1 to 52-26 may each independently be:
In an embodiment, L81 to L85 in Formulae 3-1 to 3-5 may each independently be:
In some embodiments, a group represented by
in Formulae 3-1 and 3-2 may be represented by one of Formulae CY71-1(1) to CY71-1(8),
In one or more embodiments, the second compound may include at least one of Compounds ETH1 to ETH84:
In an embodiment, the third compound may include at least one of Compounds HTH1 to HTH52:
In an embodiment, the fourth compound may include at least one of Compounds DFD1 to DFD12:
In the above Compounds, “Ph” represents a phenyl group, “D5” represents substitution with five deuterium atoms (e.g., five hydrogen atoms are replaced with five deuterium atoms), and “D4” represents substitution with four deuterium atoms (e.g., four hydrogen atoms are replaced with four deuterium atoms). For example, a group represented by
may be identical to a group represented by
In some embodiments, the light-emitting device may satisfy at least one of Conditions 1 to 4:
The highest occupied molecular orbital (HOMO) and (lowest unoccupied molecular orbital) LUMO energy levels of the first compound, the second compound, and the third compound may each be a negative value, and the HOMO and LUMO energy levels may each be an actual measurement value; or a value evaluated or calculated according to a density functional theory (DFT) method.
In one or more embodiments, the absolute value of a difference between the LUMO energy level of the first compound and the LUMO energy level of the second compound may be about 0.1 eV or higher and about 1.0 eV or lower, the absolute value of a difference between the LUMO energy level of the first compound and the LUMO energy level of the third compound may be about 0.1 eV or higher and about 1.0 eV or lower, the absolute value of a difference between the HOMO energy level of the first compound and the HOMO energy level of the second compound may be 1.25 eV or lower (e.g., about 1.25 eV or lower and about 0.2 eV or higher), and the absolute value of a difference between the HOMO energy level of the first compound and the HOMO energy level of the third compound may be 1.25 eV or lower (e.g., about 1.25 eV or lower and about 0.2 eV or higher).
When the relationships between LUMO energy level and HOMO energy level satisfy the conditions as described above, the balance between holes and electrons injected into the emission layer can be made.
The light-emitting device may have a structure of a first embodiment or a second embodiment. The first embodiment or the second embodiment is the same as described in the present specification.
According to the first embodiment, the first compound may be included in an emission layer in an interlayer of a light-emitting device, wherein the emission layer may further include a host, the first compound may be different from the host, and the emission layer may emit phosphorescence or fluorescence from the first compound. For example, according to the first embodiment, the first compound may be a dopant or an emitter. In some embodiments, the first compound may be a phosphorescent dopant or a phosphorescence emitter.
Phosphorescence or fluorescence emitted from the first compound may be blue light.
The emission layer may further include an ancillary dopant. The ancillary dopant may serve to improve luminescence efficiency from the first compound by effectively transferring energy to a dopant or the first compound as an emitter.
The ancillary dopant may be different from the first compound and the host.
In some embodiments, the ancillary dopant may be a delayed fluorescence-emitting compound.
In some embodiments, the ancillary dopant may be a compound including at least one cyclic group including boron (B) and nitrogen (N) as ring-forming atoms.
According to the second embodiment, the first compound may be included in an emission layer in an interlayer of a light-emitting device, wherein the emission layer may further include a host and a dopant, the first compound may be different from the host and the dopant, and the emission layer may emit phosphorescence or fluorescence (e.g., delayed fluorescence) from the dopant.
In an embodiment, the first compound in the second embodiment may serve as an ancillary dopant that transfers energy to a dopant (or an emitter), not as a dopant.
In some embodiments, the first compound in the second embodiment may serve as an emitter and as an ancillary dopant that transfers energy to a dopant (or an emitter).
In an embodiment, phosphorescence or fluorescence emitted from the dopant (or the emitter) in the second embodiment may be blue phosphorescence or blue fluorescence (e.g., blue delayed fluorescence).
The dopant (or the emitter) in the second embodiment may be a phosphorescent dopant material (e.g., the organometallic compound represented by Formula 1, the organometallic compound represented by Formula 401, or any combination thereof) or any suitable fluorescent dopant material (e.g., the compound represented by Formula 501, the compound represented by Formula 502, the compound represented by Formula 503, or any combination thereof).
In the first embodiment and the second embodiment, the blue light may be blue light having a maximum emission wavelength in a range of about 430 nanometers (nm) to about 490 nm, about 430 nm to about 485 nm, about 440 nm to about 475 nm, or about 455 nm to about 470 nm.
The ancillary dopant in the first embodiment may include, e.g. the fourth compound represented by Formula 502 or 503.
The host in the first embodiment and the second embodiment may be any suitable host material (e.g., the compound represented by Formula 301, the compound represented by 301-1, the compound represented by Formula 301-2, or any combination thereof).
In some embodiments, the host in the first embodiment and the second embodiment may be the second compound, the third compound, or any combination thereof.
In an embodiment, the light-emitting device may further include at least one of a first capping layer outside the first electrode and/or a second capping layer outside the second electrode, and the at least one of the first capping layer and/or the second capping layer may include the organometallic compound represented by Formula 1-1 or 1-2. More details for the first capping layer and/or second capping layer are the same as described in the present specification.
In an embodiment, the light-emitting device may further include:
The wording “(interlayer and/or capping layer) includes an organometallic compound” as used herein may be understood as “(interlayer and/or capping layer) may include one kind of organometallic compound represented by Formula 1-1 or 1-2 or two different kinds of organometallic compounds, each represented by Formula 1-1 or 1-2.”
In an embodiment, the interlayer and/or capping layer may include Compound 1 only as the organometallic compound. In this regard, Compound 1 may be present in the emission layer of the light-emitting device. In one or more embodiments, the interlayer may include, as the organometallic compound, Compound 1 and Compound 2. In this regard, Compound 1 and Compound 2 may be present in the same layer (for example, all of Compound 1 and Compound 2 may be present in the emission layer), or may be present in different layers (for example, Compound 1 may be present in the emission layer, and Compound 2 may be present in the electron transport region).
The term “interlayer,” as used herein, refers to a single layer and/or all of a plurality of layers between the first electrode and the second electrode of the light-emitting device.
Hereinafter, a structure of the light-emitting device 10 according to an embodiment and a method of manufacturing the light-emitting device 10 will be described in connection with
In
The first electrode 110 may be formed by, for example, depositing and/or sputtering a material for forming the first electrode 110 on the substrate. When the first electrode 110 is an anode, a material for forming the first electrode 110 may be a high work function material that facilitates injection of holes.
The first electrode 110 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. When the first electrode 110 is a transmissive electrode, a material for forming the first electrode 110 may include indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), zinc oxide (ZnO), or any combinations thereof. In one or more embodiments, when the first electrode 110 is a semi-transmissive electrode or a reflective electrode, magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), or any combinations thereof may be used as a material for forming a first electrode.
The first electrode 110 may have a single-layered structure consisting of a single layer or a multilayer structure including a plurality of layers. In an embodiment, the first electrode 110 may have a three-layered structure of ITO/Ag/ITO.
The interlayer 130 may be on the first electrode 110. The interlayer 130 may include an emission layer.
The interlayer 130 may further include a hole transport region between the first electrode 110 and the emission layer and an electron transport region between the emission layer and the second electrode 150.
The interlayer 130 may further include metal-containing compounds such as organometallic compounds, inorganic materials such as quantum dots, and/or the like, in addition to various suitable organic materials.
In one or more embodiments, the interlayer 130 may include, i) two or more emitting units sequentially stacked between the first electrode 110 and the second electrode 150, and ii) a charge generation layer between the two emitting units. When the interlayer 130 includes emitting units and a charge generation layer as described above, the light-emitting device 10 may be a tandem light-emitting device.
The hole transport region may have: i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer consisting of a plurality of different materials, or iii) a multi-layered structure including a plurality of layers including different materials.
The hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof.
For example, the hole transport region may have a multi-layered structure including a hole injection layer/hole transport layer structure, a hole injection layer/hole transport layer/emission auxiliary layer structure, a hole injection layer/emission auxiliary layer structure, a hole transport layer/emission auxiliary layer structure, or a hole injection layer/hole transport layer/electron blocking layer structure, the layers of each structure being stacked sequentially from the first electrode 110.
The hole transport region may include a compound represented by Formula 201, a compound represented by Formula 202, or any combination thereof:
wherein, in Formulae 201 and 202,
In an embodiment, each of Formulae 201 and 202 may include at least one of groups represented by Formulae CY201 to CY217.
wherein in Formulae CY201 to CY217, R10b and R10c may each be the same as described with respect to R10a, ring CY201 to ring CY204 may each independently be a C3-C20 carbocyclic group or a C1-C20 heterocyclic group, and at least one hydrogen in Formulae CY201 to CY217 may be unsubstituted or substituted with R10a as described above.
In an embodiment, ring CY201 to ring CY204 in Formulae CY201 to CY217 may each independently be a benzene group, a naphthalene group, a phenanthrene group, or an anthracene group.
In an embodiment, each of Formulae 201 and 202 may include at least one of groups represented by Formulae CY201 to CY203.
In an embodiment, Formula 201 may include at least one of groups represented by Formulae CY201 to CY203 and at least one of groups represented by Formulae CY204 to CY217.
In an embodiment, xa1 in Formula 201 may be 1, R201 may be a group represented by one of Formulae CY201 to CY203, xa2 may be 0, and R202 may be a group represented by one of Formulae CY204 to CY207.
In an embodiment, each of Formulae 201 and 202 may not include groups represented by Formulae CY201 to CY203.
In an embodiment, each of Formulae 201 and 202 may not include groups represented by Formulae CY201 to CY203, and may include at least one of groups represented by Formulae CY204 to CY217.
In an embodiment, each of Formulae 201 and 202 may not include groups represented by Formulae CY201 to CY217.
In an embodiment, the hole transport region may include one of Compounds HT1 to HT46, m-MTDATA, TDATA, 2-TNATA, NPB(NPD), β-NPB, TPD, Spiro-TPD, Spiro-NPB, methylated NPB, TAPC, HMTPD, 4,4',4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphor sulfonic acid (PANI/CSA), polyaniline/poly(4-styrenesulfonate) (PANI/PSS), or any combination thereof:
A thickness of the hole transport region may be in a range of about 50 Å to about 10,000 Å, for example, about 100 Å to about 4,000 Å. When the hole transport region includes a hole injection layer, a hole transport layer, or any combination thereof, a thickness of the hole injection layer may be in a range of about 100 Å to about 9,000 Å, for example, about 100 Å to about 1,000 Å, and a thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å, for example, about 100 Å to about 1,500 Å. When the thicknesses of the hole transport region, the hole injection layer and the hole transport layer are within these ranges, suitable or satisfactory hole-transporting characteristics may be obtained without a substantial increase in driving voltage.
The emission auxiliary layer may increase light-emission efficiency by compensating for an optical resonance distance according to the wavelength of light emitted by an emission layer, and the electron blocking layer may block or reduce the leakage of electrons from an emission layer to a hole transport region. Materials that may be included in the hole transport region may be included in the emission auxiliary layer and the electron blocking layer.
The hole transport region may further include, in addition to these materials, a charge-generation material for the improvement of conductive properties (e.g., electrically conductive properties). The charge-generation material may be uniformly or non-uniformly dispersed in the hole transport region (for example, in the form of a single layer consisting of a charge-generation material).
The charge-generation material may be, for example, a p-dopant.
In an embodiment, a LUMO energy level of the p-dopant may be about -3.5 eV or less.
In an embodiment, the p-dopant may include a quinone derivative, a cyano group-containing compound, a compound containing element EL1 and element EL2, or any combination thereof.
Examples of the quinone derivative may include TCNQ, F4-TCNQ, and the like.
Examples of the cyano group-containing compound may include HAT-CN, a compound represented by Formula 221 below, and the like.
In Formula 221,
In the compound containing element EL1 and element EL2, element EL1 may be metal, metalloid, or a combination thereof, and element EL2 may be non-metal, metalloid, or a combination thereof.
Examples of the metal may include: an alkali metal (for example, lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), etc.); an alkaline earth metal (for example, beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), etc.); a transition metal (for example, titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), technetium (Tc), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), etc.); a post-transition metal (for example, zinc (Zn), indium (In), tin (Sn), etc.); and a lanthanide metal (for example, lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), etc.).
Examples of the metalloid may include silicon (Si), antimony (Sb), and tellurium (Te).
Examples of the non-metal may include oxygen (O) and halogen (for example, F, Cl, Br, I, etc.).
In an embodiment, examples of the compound containing element EL1 and element EL2 may include metal oxide, metal halide (for example, metal fluoride, metal chloride, metal bromide, or metal iodide), metalloid halide (for example, metalloid fluoride, metalloid chloride, metalloid bromide, or metalloid iodide), metal telluride, or any combination thereof.
Examples of the metal oxide may include tungsten oxide (for example, WO, W2O3, WO2, WO3, W2O5, etc.), vanadium oxide (for example, VO, V2O3, VO2, V2O5, etc.), molybdenum oxide (MoO, Mo2O3, MoO2, MoO3, Mo2O5, etc.), and rhenium oxide (for example, ReO3, etc.).
Examples of the metal halide may include alkali metal halide, alkaline earth metal halide, transition metal halide, post-transition metal halide, and lanthanide metal halide.
Examples of the alkali metal halide may include LiF, NaF, KF, RbF, CsF, LiCl, NaCl, KCl, RbCl, CsCl, LiBr, NaBr, KBr, RbBr, CsBr, Lil, Nal, Kl, Rbl, and Csl.
Examples of the alkaline earth metal halide may include BeF2, MgF2, CaF2, SrF2, BaF2, BeCl2, MgCl2, CaCl2, SrCl2, BaCl2, BeBr2, MgBr2, CaBr2, SrBr2, BaBr2, Bel2, Mgl2, Cal2, Srl2, and Bal2.
Examples of the transition metal halide may include titanium halide (for example, TiF4, TiCl4, TiBr4, Til4, etc.), zirconium halide (for example, ZrF4, ZrCl4, ZrBr4, Zrl4, etc.), hafnium halide (for example, HfF4, HfCl4, HfBr4, Hfl4, etc.), vanadium halide (for example, VF3, VCl3, VBr3, Vl3, etc.), niobium halide (for example, NbF3, NbCl3, NbBr3, Nbl3, etc.), tantalum halide (for example, TaF3, TaCl3, TaBr3, Tals, etc.), chromium halide (for example, CrF3, CrCl3, CrBr3, Crl3, etc.), molybdenum halide (for example, MoF3, MoCl3, MoBr3, Mols, etc.), tungsten halide (for example, WF3, WCl3, WBr3, Wl3, etc.), manganese halide (for example, MnF2, MnCl2, MnBr2, Mnl2, etc.), technetium halide (for example, TcF2, TcCl2, TcBr2, Tcl2, etc.), rhenium halide (for example, ReF2, ReCl2, ReBr2, Rel2, etc.), iron halide (for example, FeF2, FeCl2, FeBr2, Fel2, etc.), ruthenium halide (for example, RuF2, RuCl2, RuBr2, Rul2, etc.), osmium halide (for example, OsF2, OsCl2, OsBr2, Osl2, etc.), cobalt halide (for example, CoF2, CoCl2, CoBr2, Col2, etc.), rhodium halide (for example, RhF2, RhCl2, RhBr2, Rhl2, etc.), iridium halide (for example, IrF2, IrCl2, IrBr2, Irl2, etc.), nickel halide (for example, NiF2, NiCl2, NiBr2, Nil2, etc.), palladium halide (for example, PdF2, PdCl2, PdBr2, Pdl2, etc.), platinum halide (for example, PtF2, PtCl2, PtBr2, Ptl2, etc.), copper halide (for example, CuF, CuCl, CuBr, Cul, etc.), silver halide (for example, AgF, AgCl, AgBr, Agl, etc.), and gold halide (for example, AuF, AuCl, AuBr, Aul, etc.).
Examples of the post-transition metal halide may include zinc halide (for example, ZnF2, ZnCl2, ZnBr2, Znl2, etc.), indium halide (for example, Inl3, etc.), and tin halide (for example, Snl2, etc.).
Examples of the lanthanide metal halide may include YbF, YbF2, YbF3, SmF3, YbCl, YbCl2, YbCl3 SmCl3, YbBr, YbBr2, YbBr3, SmBr3, Ybl, Ybl2, Ybl3, and Sml3.
Examples of the metalloid halide may include antimony halide (for example, SbCl5, etc.).
Examples of the metal telluride may include alkali metal telluride (for example, Li2Te, Na2Te, K2Te, Rb2Te, Cs2Te, etc.), alkaline earth metal telluride (for example, BeTe, MgTe, CaTe, SrTe, BaTe, etc.), transition metal telluride (for example, TiTe2, ZrTe2, HfTe2, V2Te3, Nb2Tes, Ta2Te3, Cr2Te3, Mo2Tes, W2Te3, MnTe, TcTe, ReTe, FeTe, RuTe, OsTe, CoTe, RhTe, IrTe, NiTe, PdTe, PtTe, Cu2Te, CuTe, Ag2Te, AgTe, Au2Te, etc.), post-transition metal telluride (for example, ZnTe, etc.), and lanthanide metal telluride (for example, LaTe, CeTe, PrTe, NdTe, PmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, etc.).
When the light-emitting device 10 is a full-color light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and/or a blue emission layer, according to a sub-pixel. In an embodiment, the emission layer may have a stacked structure of two or more layers of a red emission layer, a green emission layer, and a blue emission layer, in which the two or more layers contact each other (e.g., physically contact each other) or are separated from each other (e.g., are spaced apart from each other). In one or more embodiments, the emission layer may include two or more materials of a red light-emitting material, a green light-emitting material, and a blue light-emitting material, in which the two or more materials are mixed together with each other in a single layer to emit white light.
The emission layer may include a host and a dopant. The dopant may include a phosphorescent dopant, a fluorescent dopant, or any combination thereof.
An amount of the dopant in the emission layer may be from about 0.01 parts by weight to about 15 parts by weight based on 100 parts by weight of the host.
In an embodiment, the emission layer may include a quantum dot.
In an embodiment, the emission layer may include a delayed fluorescence material. The delayed fluorescence material may act as a host or a dopant in the emission layer.
A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å, for example, about 200 Å to about 600 Å. When the thickness of the emission layer is within the above ranges, excellent light-emission characteristics may be obtained without a substantial increase in driving voltage.
The host may include a compound represented by Formula 301 below:
wherein, in Formula 301,
In an embodiment, when xb11 in Formula 301 is 2 or more, two or more of Ar301(s) may be linked to each other via a single bond.
In an embodiment, the host may include a compound represented by Formula 301-1, a compound represented by Formula 301-2, or any combination thereof:
wherein, in Formulae 301-1 and 301-2,
In an embodiment, the host may include an alkali earth metal complex, a post-transition metal complex, or a combination thereof. In an embodiment, the host may include a Be complex (for example, Compound H55), an Mg complex, a Zn complex, or a combination thereof.
In an embodiment, the host may include one of Compounds H1 to H124, 9,10-di(2-naphthyl)anthracene (ADN), 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN), 9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN), 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene (mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), or any combination thereof:
The phosphorescent dopant may include at least one transition metal as a central metal atom.
The phosphorescent dopant may include a monodentate ligand, a bidentate ligand, a tridentate ligand, a tetradentate ligand, a pentadentate ligand, a hexadentate ligand, or any combination thereof.
The phosphorescent dopant may be electrically neutral.
In an embodiment, the phosphorescent dopant may include an organometallic compound represented by Formula 401:
wherein, in Formulae 401 and 402,
In an embodiment, in Formula 402, i) X401 may be nitrogen, and X402 may be carbon, or ii) each of X401 and X402 may be nitrogen.
In an embodiment, when xc1 in Formula 402 is 2 or more, two ring A401 in two or more of L401(s) may be optionally linked to each other via T402, which is a linking group, and two ring A402 may optionally be linked to each other via T403, which is a linking group (see Compounds PD1 to PD4 and PD7). T402 and T403 are the same as described in connection with T401.
L402 in Formula 401 may be an organic ligand. In an embodiment, L402 may include a halogen group, a diketone group (for example, an acetylacetonate group), a carboxylic acid group (for example, a picolinate group), —C(═O), an isonitrile group, —CN group, a phosphorus group (for example, a phosphine group, a phosphite group, etc.), or any combination thereof.
The phosphorescent dopant may include, for example, one of compounds PD1 to PD39, or any combination thereof:
The fluorescent dopant may include an amine group-containing compound, a styryl group-containing compound, or any combination thereof.
wherein, in Formula 501,
In an embodiment, Ar501 in Formula 501 may be a condensed cyclic group (for example, an anthracene group, a chrysene group, or a pyrene group) in which three or more monocyclic groups are condensed together.
In an embodiment, xd4 in Formula 501 may be 2.
In an embodiment, the fluorescent dopant may include: one of Compounds FD1 to FD36; DPVBi; DPAVBi; or any combination thereof:
The emission layer may include a delayed fluorescence material.
In the present specification, the delayed fluorescence material may be selected from compounds capable of emitting delayed fluorescence based on a delayed fluorescence emission mechanism.
The delayed fluorescence material included in the emission layer may act as a host or a dopant depending on the type or kind of other materials included in the emission layer.
In an embodiment, the difference between the triplet energy level (eV) of the delayed fluorescence material and the singlet energy level (eV) of the delayed fluorescence material may be greater than or equal to 0 eV and less than or equal to 0.5 eV. When the difference between the triplet energy level (eV) of the delayed fluorescence material and the singlet energy level (eV) of the delayed fluorescence material satisfies the above-described range, up-conversion from the triplet state to the singlet state of the delayed fluorescence materials may effectively occur, and thus, the luminescence efficiency of the light-emitting device 10 may be improved.
In an embodiment, the delayed fluorescence material may include i) a material including at least one electron donor (for example, a π electron-rich C3-C60 cyclic group, such as a carbazole group) and at least one electron acceptor (for example, a sulfoxide group, a cyano group, or a π electron-deficient nitrogen-containing C1-C60 cyclic group), and ii) a material including a C8-C60 polycyclic group in which two or more cyclic groups are condensed together while sharing boron (B).
Examples of the delayed fluorescence material may include at least one of the following Compounds DF1 to DF9:
The emission layer may include a quantum dot.
In the present specification, a quantum dot refers to a crystal of a semiconductor compound, and may include any suitable material capable of emitting light of various suitable emission wavelengths according to the size of the crystal.
A diameter of the quantum dot may be, for example, in a range of about 1 nm to about 10 nm.
The quantum dot may be synthesized by a wet chemical process, a metal organic chemical vapor deposition process, a molecular beam epitaxy process, and/or any suitable process similar thereto.
According to the wet chemical process, a precursor material is mixed together with an organic solvent to grow a quantum dot particle crystal. When the crystal grows, the organic solvent naturally acts as a dispersant coordinated on the surface of the quantum dot crystal and controls the growth of the crystal so that the growth of quantum dot particles may be controlled through a process which is more easily performed than vapor deposition methods, such as metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE), and which requires low costs.
The quantum dot may include: a Group II-VI semiconductor compound; a Group III-V semiconductor compound; a Group III-VI semiconductor compound; a Group I-III-VI semiconductor compound; a Group IV-VI semiconductor compound; a Group IV element or compound; or any combination thereof.
Examples of the Group II-VI semiconductor compound may include: a binary compound, such as CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, or MgS; a ternary compound, such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, or MgZnS; a quaternary compound, such as CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, or HgZnSTe; or any combination thereof.
Examples of the Group III-V semiconductor compound may include: a binary compound, such as GaN, GaP, GaAs, GaSb, AIN, AIP, AlAs, AlSb, InN, InP, InAs, or InSb; a ternary compound, such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAIP, InNAs, InNSb, InPAs, or InPSb; a quaternary compound, such as GaAINP, GaAINAs, GaAINSb, GaAlPAs, GaAlPSb, GalnNP, GalnNAs, GalnNSb, GalnPAs, GalnPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, or InAlPSb; or any combination thereof. In an embodiment, the Group III-V semiconductor compound may further include Group II elements. Examples of the Group III-V semiconductor compound further including Group II elements may include InZnP, InGaZnP, InAlZnP, and the like.
Examples of the Group III-VI semiconductor compound may include: a binary compound, such as GaS, GaSe, Ga2Se3, GaTe, InS, InSe, In2S3, In2Se3, or InTe; a ternary compound, such as InGaS3, or InGaSe3; or any combination thereof.
Examples of the Group I-III-VI semiconductor compound may include: a ternary compound, such as AglnS, AglnS2, CulnS, CulnS2, CuGaO2, AgGaO2, or AgAlO2; or any combination thereof.
Examples of the Group IV-VI semiconductor compound may include: a binary compound, such as SnS, SnSe, SnTe, PbS, PbSe, PbTe, or the like; a ternary compound, such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, or the like; a quaternary compound, such as SnPbSSe, SnPbSeTe, SnPbSTe, or the like; or any combination thereof.
The Group IV element or compound may include: a single element compound, such as Si or Ge; a binary compound, such as SiC or SiGe; or any combination thereof.
Each element included in a multi-element compound such as the binary compound, ternary compound and quaternary compound, may exist in a particle having a uniform concentration or non-uniform concentration.
In an embodiment, the quantum dot may have a single structure or a dual core-shell structure. In the case of the quantum dot having a single structure, the concentration of each element included in the corresponding quantum dot is uniform (e.g., substantially uniform). In an embodiment, the material contained in the core and the material contained in the shell may be different from each other.
The shell of the quantum dot may act as a protective layer to prevent or reduce chemical degeneration of the core to maintain semiconductor characteristics and/or as a charging layer to impart electrophoretic characteristics to the quantum dot. The shell may be a single layer or a multi-layer. The element presented in the interface between the core and the shell of the quantum dot may have a concentration gradient that decreases along a direction toward the center of the quantum dot.
Examples of the shell of the quantum dot may be an oxide of metal, metalloid, or non-metal, a semiconductor compound, and any combination thereof. Examples of the oxide of metal, metalloid, or non-metal may include: a binary compound, such as SiO2, Al2O3, TiO2, ZnO, MnO, Mn2O3, Mn3O4, CuO, FeO, Fe2O3, Fe3O4, CoO, Co3O4, or NiO; a ternary compound, such as MgAl2O4, CoFe2O4, NiFe2O4, or CoMn2O4; or any combination thereof. Examples of the semiconductor compound may include, as described herein, a Group II-VI semiconductor compound, a Group III-V semiconductor compound, a Group III-VI semiconductor compound, a Group I-III-VI semiconductor compound, a Group IV-VI semiconductor compound, or any combination thereof. In addition, the semiconductor compound may include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AIP, AlSb, or any combination thereof.
A full width at half maximum (FWHM) of an emission wavelength spectrum of the quantum dot may be about 45 nm or less, for example, about 40 nm or less, for example, about 30 nm or less, and within these ranges, color purity or color reproducibility may be increased. In addition, because the light emitted through the quantum dot is emitted in all directions (or substantially all directions), the wide viewing angle can be improved.
In addition, the quantum dot may be a spherical particle, a pyramidal particle, a multi-arm particle, a cubic nanoparticle, a nanotube particle, a nanowire particle, a nanofiber particle, or a nanoplate particle.
Because the energy band gap can be adjusted by controlling the size of the quantum dot, light having various suitable wavelength bands can be obtained from the quantum dot emission layer. Therefore, by using quantum dots of different sizes, a light-emitting device that emits light of various suitable wavelengths may be implemented. In an embodiment, the size of the quantum dot may be selected to emit red, green and/or blue light. In addition, the size of the quantum dot may be configured to emit white light by combining light of various suitable colors.
The electron transport region may have: i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer consisting of a plurality of different materials, or iii) a multi-layered structure including a plurality of layers including different materials.
The electron transport region may include a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, an electron injection layer, or any combination thereof.
For example, the electron transport region may have an electron transport layer/electron injection layer structure, a hole-blocking layer/electron transport layer/electron injection layer structure, an electron control layer/electron transport layer/electron injection layer structure, or a buffer layer/electron transport layer/electron injection layer structure, the constituting layers of each structure being sequentially stacked from an emission layer.
In an embodiment, the electron transport region (for example, the buffer layer, the hole-blocking layer, the electron control layer, or the electron transport layer in the electron transport region) may include a metal-free compound including at least one π electron-deficient nitrogen-containing C1-C60 cyclic group.
In an embodiment, the electron transport region may include a compound represented by Formula 601 below:
wherein, in Formula 601,
In an embodiment, when xe11 in Formula 601 is 2 or more, two or more of Ar601 (s) may be linked via a single bond.
In an embodiment, Ar601 in Formula 601 may be a substituted or unsubstituted anthracene group.
In an embodiment, the electron transport region may include a compound represented by Formula 601-1:
wherein, in Formula 601-1,
In an embodiment, xe1 and xe611 to xe613 in Formulae 601 and 601-1 may each independently be 0, 1, or 2.
The electron transport region may include one of Compounds ET1 to ET45, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), Alq3, BAlq, TAZ, NTAZ, or any combination thereof:
A thickness of the electron transport region may be from about 100 Å to about 5,000 Å, for example, about 160 Å to about 4,000 Å. When the electron transport region includes a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, or any combination thereof, the thickness of the buffer layer, the hole blocking layer, or the electron control layer may each independently be from about 20 Å to about 1000 Å, for example, about 30 Å to about 300 Å, and the thickness of the electron transport layer may be from about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. When the thickness of the buffer layer, the hole blocking layer, the electron control layer, the electron transport layer, and/or the electron transport region are within these ranges, suitable or satisfactory electron transporting characteristics may be obtained without a substantial increase in driving voltage.
The electron transport region (for example, the electron transport layer in the electron transport region) may further include, in addition to the materials described above, a metal-containing material.
The metal-containing material may include an alkali metal complex, an alkaline earth metal complex, or any combination thereof. A metal ion of the alkali metal complex may be a Li ion, a Na ion, a K ion, a Rb ion, or a Cs ion, and a metal ion of the alkaline earth metal complex may be a Be ion, a Mg ion, a Ca ion, a Sr ion, or a Ba ion. A ligand coordinated with the metal ion of the alkali metal complex or the alkaline earth-metal complex may include a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyloxazole, a hydroxyphenylthiazole, a hydroxyphenyloxadiazole, a hydroxyphenylthiadiazole, a hydroxyphenylpyridine, a hydroxyphenylbenzimidazole, a hydroxyphenylbenzothiazole, a bipyridine, a phenanthroline, a cyclopentadiene, or any combination thereof.
In an embodiment, the metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (LiQ) or ET-D2:
The electron transport region may include an electron injection layer that facilitates the injection of electrons from the second electrode 150. The electron injection layer may be in direct contact with the second electrode 150.
The electron injection layer may have: i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer consisting of a plurality of different materials, or iii) a multi-layered structure including a plurality of layers including different materials.
The electron injection layer may include an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof.
The alkali metal may include Li, Na, K, Rb, Cs, or any combination thereof. The alkaline earth metal may include Mg, Ca, Sr, Ba, or any combination thereof. The rare earth metal may include Sc, Y, Ce, Tb, Yb, Gd, or any combination thereof.
The alkali metal-containing compound, the alkaline earth metal-containing compound, and the rare earth metal-containing compound may include oxides, halides (for example, fluorides, chlorides, bromides, or iodides), or tellurides of the alkali metal, the alkaline earth metal, and the rare earth metal, or any combination thereof.
The alkali metal-containing compound may include alkali metal oxides, such as Li2O, Cs2O, or K2O, alkali metal halides, such as LiF, NaF, CsF, KF, Lil, Nal, Csl, or KI, or any combination thereof. The alkaline earth metal-containing compound may include an alkaline earth metal compound, such as BaO, SrO, CaO, BaxSr1-xO (x is a real number satisfying the condition of 0<x<1), BaxCa1-xO (x is a real number satisfying the condition of 0<x<1), or the like. The rare earth metal-containing compound may include YbF3, ScF3, Sc2O3, Y2O3, Ce2O3, GdF3, TbF3, Ybl3, Scl3, Tbl3, or any combination thereof. In an embodiment, the rare earth metal-containing compound may include lanthanide metal telluride. Examples of the lanthanide metal telluride may include LaTe, CeTe, PrTe, NdTe, PmTe, SmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, La2Te3, Ce2Te3, Pr2Te3, Nd2Te3, Pm2Te3, Sm2Te3, Eu2Te3, Gd2Tes, Tb2Te3, Dy2Tes, Ho2Te3, Er2Te3, Tm2Tes, Yb2Te3, and Lu2Te3.
The alkali metal complex, the alkaline earth-metal complex, and the rare earth metal complex may include i) one of ions of the alkali metal, the alkaline earth metal, and the rare earth metal and ii), as a ligand bonded to the metal ion, for example, a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyloxazole, a hydroxyphenylthiazole, a hydroxyphenyloxadiazole, a hydroxyphenylthiadiazole, a hydroxyphenylpyridine, a hydroxyphenyl benzimidazole, a hydroxyphenylbenzothiazole, a bipyridine, a phenanthroline, a cyclopentadiene, or any combination thereof.
The electron injection layer may include (or consist of) an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof, as described above. In an embodiment, the electron injection layer may further include an organic material (for example, a compound represented by Formula 601).
In an embodiment, the electron injection layer may include (or consist of) i) an alkali metal-containing compound (for example, an alkali metal halide), ii) a) an alkali metal-containing compound (for example, an alkali metal halide); and b) an alkali metal, an alkaline earth metal, a rare earth metal, or any combination thereof. For example, the electron injection layer may be a KI:Yb co-deposited layer, a Rbl:Yb co-deposited layer, a LiF:Yb co-deposited, and/or the like.
When the electron injection layer further includes an organic material, alkali metal, alkaline earth metal, rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, alkali metal complex, alkaline earth-metal complex, rare earth metal complex, or any combination thereof may be homogeneously or non-homogeneously dispersed in a matrix including the organic material.
A thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å, and, for example, about 3 Å to about 90 Å. When the thickness of the electron injection layer is within the range described above, suitable or satisfactory electron injection characteristics may be obtained without a substantial increase in driving voltage.
The second electrode 150 may be on the interlayer 130 having such a structure. The second electrode 150 may be a cathode, which is an electron injection electrode, and as the material for the second electrode 150, a metal, an alloy, an electrically conductive compound, or any combination thereof, each having a low work function, may be used.
In an embodiment, the second electrode 150 may include lithium (Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), ytterbium (Yb), silver-ytterbium (Ag—Yb), ITO, IZO, or a combination thereof. The second electrode 150 may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode.
The second electrode 150 may have a single-layered structure or a multi-layered structure including two or more layers.
A first capping layer may be outside the first electrode 110, and/or a second capping layer may be outside the second electrode 150. In more detail, the light-emitting device 10 may have a structure in which the first capping layer, the first electrode 110, the interlayer 130, and the second electrode 150 are sequentially stacked in this stated order, a structure in which the first electrode 110, the interlayer 130, the second electrode 150, and the second capping layer are sequentially stacked in this stated order, or a structure in which the first capping layer, the first electrode 110, the interlayer 130, the second electrode 150, and the second capping layer are sequentially stacked in this stated order.
Light generated in an emission layer of the interlayer 130 of the light-emitting device 10 may be extracted toward the outside through the first electrode 110, which is a semi-transmissive electrode or a transmissive electrode, and the first capping layer or light generated in an emission layer of the interlayer 130 of the light-emitting device 10 may be extracted toward the outside through the second electrode 150, which is a semi-transmissive electrode or a transmissive electrode, and the second capping layer.
The first capping layer and the second capping layer may increase external emission efficiency according to the principle of constructive interference. Accordingly, the light extraction efficiency of the light-emitting device 10 is increased, so that the emission efficiency of the light-emitting device 10 may be improved.
Each of the first capping layer and second capping layer may include a material having a refractive index (at a wavelength of 589 nm) of 1.6 or more.
The first capping layer and the second capping layer may each independently be an organic capping layer including an organic material, an inorganic capping layer including an inorganic material, or an organic-inorganic composite capping layer including an organic material and an inorganic material.
At least one of the first capping layer and the second capping layer may each independently include carbocyclic compounds, heterocyclic compounds, amine group-containing compounds, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, alkali metal complexes, alkaline earth metal complexes, or any combination thereof. The carbocyclic compound, the heterocyclic compound, and the amine group-containing compound may be optionally substituted with a substituent containing O, N, S, Se, Si, F, Cl, Br, I, or any combination thereof. In an embodiment, at least one of the first capping layer and the second capping layer may each independently include an amine group-containing compound.
In an embodiment, at least one of the first capping layer and the second capping layer may each independently include a compound represented by Formula 201, a compound represented by Formula 202, or any combination thereof.
In an embodiment, at least one of the first capping layer and the second capping layer may each independently include one of Compounds HT28 to HT33, one of Compounds CP1 to CP6, β-NPB, or any combination thereof:
The organometallic compound represented by Formula 1-1 or 1-2 may be included in various suitable films. Accordingly, according to one or more embodiments, a film including the organometallic compound represented by Formula 1-1 or 1-2 may be provided. The film may be, for example, an optical member (e.g., a light control means such as, for example, a color filter, a color conversion member, a capping layer, a light extraction efficiency enhancement layer, a selective light absorbing layer, a polarizing layer, a quantum dot-containing layer, and/or like), a light-blocking member (for example, a light reflective layer, a light absorbing layer, and/or the like), and/or a protective member (for example, an insulating layer, a dielectric layer, and/or the like).
The light-emitting device may be included in various suitable electronic apparatuses. In an embodiment, the electronic apparatus including the light-emitting device may be a light-emitting apparatus, an authentication apparatus, and/or the like.
The electronic apparatus (for example, light-emitting apparatus) may further include, in addition to the light-emitting device, i) a color filter, ii) a color conversion layer, or iii) a color filter and a color conversion layer. The color filter and/or the color conversion layer may be in at least one traveling direction of light emitted from the light-emitting device. For example, the light emitted from the light-emitting device may be blue light or white light. The light-emitting device may be the same as described above. In an embodiment, the color conversion layer may include quantum dots. The quantum dot may be, for example, a quantum dot as described herein.
The electronic apparatus may include a first substrate. The first substrate may include a plurality of subpixel areas, the color filter may include a plurality of color filter areas respectively corresponding to the subpixel areas, and the color conversion layer may include a plurality of color conversion areas respectively corresponding to the subpixel areas.
A pixel-defining film may be located among the subpixel areas to define each of the subpixel areas.
The color filter may further include a plurality of color filter areas and light-shielding patterns located among the color filter areas, and the color conversion layer may include a plurality of color conversion areas and light-shielding patterns located among the color conversion areas.
The color filter areas (or the color conversion areas) may include a first area that emits a first color light, a second area that emits a second color light, and/or a third area that emits a third color light, and the first color light, the second color light, and/or the third color light may have different maximum emission wavelengths from one another. In an embodiment, the first color light may be red light, the second color light may be green light, and the third color light may be blue light. In an embodiment, the color filter areas (or the color conversion areas) may include quantum dots. In more detail, the first area may include a red quantum dot, the second area may include a green quantum dot, and the third area may not include a quantum dot. The quantum dot is the same as described in the present specification. The first area, the second area, and/or the third area may each further include a scatterer (e.g., a light scatterer).
In an embodiment, the light-emitting device may emit a first light, the first area may absorb the first light to emit a first first-color light, the second area may absorb the first light to emit a second first-color light, and the third area may absorb the first light to emit a third first-color light. In this regard, the first first-color light, the second first-color light, and the third first-color light may have different maximum emission wavelengths. In more detail, the first light may be blue light, the first first-color light may be red light, the second first-color light may be green light, and the third first-color light may be blue light.
The electronic apparatus may further include a thin-film transistor in addition to the light-emitting device as described above. The thin-film transistor may include a source electrode, a drain electrode, and an activation layer, wherein any one of the source electrode or the drain electrode may be electrically connected to any one of the first electrode or the second electrode of the light-emitting device.
The thin-film transistor may further include a gate electrode, a gate insulating film, etc.
The activation layer may include crystalline silicon, amorphous silicon, organic semiconductor, oxide semiconductor, and/or the like.
The electronic apparatus may further include a sealing portion for sealing the light-emitting device. The sealing portion and/or the color conversion layer may be between the color filter and the light-emitting device. The sealing portion allows light from the light-emitting device to be extracted to the outside, while concurrently (e.g., simultaneously) preventing or reducing penetration of ambient air and/or moisture into the light-emitting device. The sealing portion may be a sealing substrate including a transparent glass substrate and/or a plastic substrate. The sealing portion may be a thin-film encapsulation layer including at least one layer of an organic layer and/or an inorganic layer. When the sealing portion is a thin film encapsulation layer, the electronic apparatus may be flexible.
Various suitable functional layers may be additionally on the sealing portion, in addition to the color filter and/or the color conversion layer, according to the use of the electronic apparatus. The functional layers may include a touch screen layer, a polarizing layer, and/or the like. The touch screen layer may be a pressure-sensitive touch screen layer, a capacitive touch screen layer, and/or an infrared touch screen layer.
The authentication apparatus may further include, in addition to the light-emitting device, a biometric information collector. The authentication apparatus may be, for example, a biometric authentication apparatus that authenticates an individual by using biometric information of a living body (for example, fingertips, pupils, etc.).
The electronic apparatus may be applied to various suitable displays, light sources, lighting, personal computers (for example, a mobile personal computer), mobile phones, digital cameras, electronic diaries, electronic dictionaries, electronic game machines, medical instruments (for example, electronic thermometers, sphygmomanometers, blood glucose meters, pulse measurement devices, pulse wave measurement devices, electrocardiogram displays, ultrasonic diagnostic devices, and/or endoscope displays), fish finders, various suitable measuring instruments, meters (for example, meters for a vehicle, an aircraft, and/or a vessel), projectors, and/or the like.
The light-emitting apparatus of
The substrate 100 may be a flexible substrate, a glass substrate, and/or a metal substrate. A buffer layer 210 may be on the substrate 100. The buffer layer 210 may prevent or reduce penetration of impurities through the substrate 100 and may provide a flat surface on the substrate 100.
A TFT may be on the buffer layer 210. The TFT may include an activation layer 220, a gate electrode 240, a source electrode 260, and a drain electrode 270.
The activation layer 220 may include an inorganic semiconductor such as silicon and/or polysilicon, an organic semiconductor, and/or an oxide semiconductor, and may include a source region, a drain region, and a channel region.
A gate insulating film 230 for insulating the activation layer 220 from the gate electrode 240 may be on the activation layer 220, and the gate electrode 240 may be on the gate insulating film 230.
An interlayer insulating film 250 is on the gate electrode 240. The interlayer insulating film 250 may be between the gate electrode 240 and the source electrode 260 to insulate the gate electrode 240 from the source electrode 260 and between the gate electrode 240 and the drain electrode 270 to insulate the gate electrode 240 from the drain electrode 270.
The source electrode 260 and the drain electrode 270 may be on the interlayer insulating film 250. The interlayer insulating film 250 and the gate insulating film 230 may expose the source region and the drain region of the activation layer 220, and the source electrode 260 and the drain electrode 270 may be in contact (e.g., physical contact) with the exposed portions of the source region and the drain region, respectively, of the activation layer 220.
The TFT is electrically connected to a light-emitting device to drive the light-emitting device, and is covered by a passivation layer 280. The passivation layer 280 may include an inorganic insulating film, an organic insulating film, or a combination thereof. A light-emitting device is provided on the passivation layer 280. The light-emitting device may include a first electrode 110, an interlayer 130, and a second electrode 150.
The first electrode 110 may be on the passivation layer 280. The passivation layer 280 does not completely cover the drain electrode 270 and exposes a portion of the drain electrode 270, and the first electrode 110 is connected to the exposed portion of the drain electrode 270.
A pixel-defining layer 290 containing an insulating material may be on the first electrode 110. The pixel-defining layer 290 exposes a region of the first electrode 110, and an interlayer 130 may be in the exposed region of the first electrode 110. The pixel-defining layer 290 may be a polyimide and/or polyacrylic organic film. In some embodiments, at least some layers of the interlayer 130 may extend beyond the upper portion of the pixel-defining layer 290 in the form of a common layer.
The second electrode 150 may be on the interlayer 130, and a capping layer 170 may be additionally on the second electrode 150. The capping layer 170 may cover the second electrode 150.
The encapsulation portion 300 may be on the capping layer 170. The encapsulation portion 300 may be on a light-emitting device to protect the light-emitting device from moisture and/or oxygen. The encapsulation portion 300 may include: an inorganic film including silicon nitride (SiNx), silicon oxide (SiOx), indium tin oxide, indium zinc oxide, or any combination thereof; an organic film including polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxymethylene, polyarylate, hexamethyldisiloxane, an acrylic resin (for example, polymethyl methacrylate, polyacrylic acid, and/or the like), an epoxy-based resin (for example, aliphatic glycidyl ether (AGE), and/or the like), or a combination thereof; or a combination of the inorganic film and the organic film.
The light-emitting apparatus of
Respective layers included in the hole transport region, the emission layer, and respective layers included in the electron transport region may be formed in a certain region by using one or more suitable methods selected from vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, and laser-induced thermal imaging.
When layers constituting the hole transport region, an emission layer, and layers constituting the electron transport region are formed by vacuum deposition, the deposition may be performed at a deposition temperature of about 100° C. to about 500° C., a vacuum degree of about 10-8 torr to about 10-3 torr, and a deposition speed of about 0.01 Å/sec to about 100 Å/sec, depending on a material to be included in a layer to be formed and the structure of a layer to be formed.
The term “C3-C60 carbocyclic group,” as used herein, refers to a cyclic group consisting of carbon only as a ring-forming atom and having three to sixty carbon atoms, and the term “C1-C60 heterocyclic group,” as used herein, refers to a cyclic group that has one to sixty carbon atoms and further has, in addition to carbon, a heteroatom as a ring-forming atom. The C3-C60 carbocyclic group and the C1-C60 heterocyclic group may each be a monocyclic group consisting of one ring or a polycyclic group in which two or more rings are condensed together with each other. In an embodiment, the C1-C60 heterocyclic group has 3 to 61 ring-forming atoms.
The term “cyclic group,” as used herein, may include the C3-C60 carbocyclic group and the C1-C60 heterocyclic group.
The term “π electron-rich C3-C60 cyclic group,” as used herein, refers to a cyclic group that has three to sixty carbon atoms and does not include *—N═*’ as a ring-forming moiety, and the term “π electron-deficient nitrogen-containing C1-C60 cyclic group,” as used herein, refers to a heterocyclic group that has one to sixty carbon atoms and includes *—N═*’ as a ring-forming moiety.
In an embodiment,
The term “cyclic group”, “C3-C60 carbocyclic group”, “C1-C60 heterocyclic group”, “π electron-rich C3-C60 cyclic group”, or “π electron-deficient nitrogen-containing C1-C60 cyclic group,” as used herein, refers to a group condensed to any cyclic group or a polyvalent group (for example, a divalent group, a trivalent group, a tetravalent group, etc.), depending on the structure of a formula in connection with which the terms are used. In an embodiment, “a benzene group” may be a benzo group, a phenyl group, a phenylene group, or the like, which may be easily understood by one of ordinary skill in the art according to the structure of a formula including the “benzene group.”
Examples of the monovalent C3-C60 carbocyclic group and the monovalent C1-C60 heterocyclic group may include a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, and examples of the divalent C3-C60 carbocyclic group and the monovalent C1-C60 heterocyclic group may include a C3-C10 cycloalkylene group, a C1-C10 heterocycloalkylene group, a C3-C10 cycloalkenylene group, a C1-C10 heterocycloalkenylene group, a C6-C60 arylene group, a C1-C60 heteroarylene group, a divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group.
The term “C1-C60 alkyl group,” as used herein, refers to a linear or branched aliphatic hydrocarbon monovalent group that has one to sixty carbon atoms, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neopentyl group, an isopentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group, an isodecyl group, a sec-decyl group, and a tert-decyl group. The term “C1-C60 alkylene group,” as used herein, refers to a divalent group having substantially the same structure as the C1-C60 alkyl group.
The term “C2-C60 alkenyl group,” as used herein, refers to a monovalent hydrocarbon group having at least one carbon-carbon double bond at a main chain (e.g., in the middle) or at a terminal end (e.g., the terminus) of the C2-C60 alkyl group, and examples thereof include an ethenyl group, a propenyl group, and a butenyl group. The term “C2-C60 alkenylene group,” as used herein, refers to a divalent group having substantially the same structure as the C2-C60 alkenyl group.
The term “C2-C60 alkynyl group,” as used herein, refers to a monovalent hydrocarbon group having at least one carbon-carbon triple bond at a main chain (e.g., in the middle) or at a terminal end (e.g., the terminus) of the C2-C60 alkyl group, and examples thereof include an ethynyl group and a propynyl group. The term “C2-C60 alkynylene group,” as used herein, refers to a divalent group having substantially the same structure as the C2-C60 alkynyl group.
The term “C1-C60 alkoxy group,” as used herein, refers to a monovalent group represented by -OA101 (wherein A101 is the C1-C60 alkyl group), and examples thereof include a methoxy group, an ethoxy group, and an isopropyloxy group.
The term “C3-C10 cycloalkyl group,” as used herein, refers to a monovalent saturated hydrocarbon cyclic group having 3 to 10 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group (or a bicyclo[2.2.1]heptyl group), a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, and a bicyclo[2.2.2]octyl group. The term “C3-C10 cycloalkylene group,” as used herein, refers to a divalent group having substantially the same structure as the C3-C10 cycloalkyl group.
The term “C1-C10 heterocycloalkyl group,” as used herein, refers to a monovalent cyclic group that further includes, in addition to a carbon atom, at least one heteroatom as a ring-forming atom and has 1 to 10 carbon atoms, and examples thereof include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term “C1-C10 heterocycloalkylene group,” as used herein, refers to a divalent group having substantially the same structure as the C1-C10 heterocycloalkyl group.
The term “C3-C10 cycloalkenyl group,” as used herein, refers to a monovalent cyclic group that has three to ten carbon atoms and at least one carbon-carbon double bond in the ring thereof and no aromaticity (e.g., is not aromatic), and examples thereof include a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. The term “C3-C10 cycloalkenylene group,” as used herein, refers to a divalent group having substantially the same structure as the C3-C10 cycloalkenyl group.
The term “C1-C10 heterocycloalkenyl group,” as used herein, refers to a monovalent cyclic group that has, in addition to a carbon atom, at least one heteroatom as a ring-forming atom, 1 to 10 carbon atoms, and at least one carbon-carbon double bond in the cyclic structure thereof. Examples of the C1-C10 heterocycloalkenyl group include a 4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, and a 2,3-dihydrothiophenyl group. The term “C1-C10 heterocycloalkenylene group,” as used herein, refers to a divalent group having substantially the same structure as the C1-C10 heterocycloalkenyl group.
The term “C6-C60 aryl group,” as used herein, refers to a monovalent group having a carbocyclic aromatic system having six to sixty carbon atoms, and the term “C6-C60 arylene group,” as used herein, refers to a divalent group having a carbocyclic aromatic system having six to sixty carbon atoms. Examples of the C6-C60 aryl group include a phenyl group, a pentalenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a heptalenyl group, a naphthacenyl group, a picenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, and an ovalenyl group. When the C6-C60 aryl group and the C6-C60 arylene group each include two or more rings, the rings may be condensed together with each other.
The term “C1-C60 heteroaryl group,” as used herein, refers to a monovalent group having a heterocyclic aromatic system that has, in addition to a carbon atom, at least one heteroatom as a ring-forming atom, and 1 to 60 carbon atoms. The term “C1-C60 heteroarylene group,” as used herein, refers to a divalent group having a heterocyclic aromatic system that has, in addition to a carbon atom, at least one heteroatom as a ring-forming atom, and 1 to 60 carbon atoms. Examples of the C1-C60 heteroaryl group include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, a benzoquinolinyl group, an isoquinolinyl group, a benzoisoquinolinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a phthalazinyl group, and a naphthyridinyl group. When the C1-C60 heteroaryl group and the C1-C60 heteroarylene group each include two or more rings, the rings may be condensed together with each other.
The term “monovalent non-aromatic condensed polycyclic group,” as used herein, refers to a monovalent group having two or more rings condensed to each other, only carbon atoms (for example, having 8 to 60 carbon atoms) as ring-forming atoms, and non-aromaticity in its molecular structure when considered as a whole (e.g., is not aromatic when considered as a whole). Examples of the monovalent non-aromatic condensed polycyclic group include an indenyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, an indenophenanthrenyl group, and an indeno anthracenyl group. The term “divalent non-aromatic condensed polycyclic group,” as used herein, refers to a divalent group having substantially the same structure as a monovalent non-aromatic condensed polycyclic group.
The term “monovalent non-aromatic condensed heteropolycyclic group,” as used herein, refers to a monovalent group having two or more rings condensed to each other, at least one heteroatom other than carbon atoms (for example, having 1 to 60 carbon atoms), as a ring-forming atom, and non-aromaticity in its molecular structure when considered as a whole (e.g., is not aromatic when considered as a whole). Examples of the monovalent non-aromatic condensed heteropolycyclic group include a pyrrolyl group, a thiophenyl group, a furanyl group, an indolyl group, a benzoindolyl group, a naphthoindolyl group, an isoindolyl group, a benzoisoindolyl group, a naphthoisoindolyl group, a benzosilolyl group, a benzothiophenyl group, a benzofuranyl group, a carbazolyl group, a dibenzosilolyl group, a dibenzothiophenyl group, a dibenzofuranyl group, an azacarbazolyl group, an azafluorenyl group, an azadibenzosilolyl group, an azadibenzothiophenyl group, an azadibenzofuranyl group, a pyrazolyl group, an imidazolyl group, a triazolyl group, a tetrazolyl group, an oxazolyl group, an isoxazolyl group, a thiazolyl group, an isothiazolyl group, an oxadiazolyl group, a thiadiazolyl group, a benzopyrazolyl group, a benzimidazolyl group, a benzoxazolyl group, a benzothiazolyl group, a benzoxadiazolyl group, a benzothiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an imidazotriazinyl group, an imidazopyrazinyl group, an imidazopyridazinyl group, an indeno carbazolyl group, an indolocarbazolyl group, a benzofurocarbazolyl group, a benzothienocarbazolyl group, a benzosilolocarbazolyl group, a benzoindolocarbazolyl group, a benzocarbazolyl group, a benzonaphthofuranyl group, a benzonaphthothiophenyl group, a benzonaphtho silolyl group, a benzofurodibenzofuranyl group, a benzofurodibenzothiophenyl group, and a benzothienodibenzothiophenyl group. The term “divalent non-aromatic condensed heteropolycyclic group,” as used herein, refers to a divalent group having substantially the same structure as a monovalent non-aromatic condensed heteropolycyclic group.
The term “C6-C60 aryloxy group,” as used herein, indicates -OA102 (wherein A102 is the C6-C60 aryl group), and the term “C6-C60 arylthio group,” as used herein, indicates -SA103 (wherein A103 is the C6-C60 aryl group).
The term “C7-C60 aryl alkyl group,” used herein, refers to -A104A105 (where A104 may be a C1-C54 alkylene group, and A105 may be a C6-C59 aryl group), and the term “C2-C60 heteroaryl alkyl group,” as used herein, refers to -A106A107 (where A106 may be a C1-C59 alkylene group, and A107 may be a C1-C59 heteroaryl group).
R10a may be:
Q1 to Q3, Q11 to Q13, Q21 to Q23, and Q31 to Q33 used herein may each independently be: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; a C1-C60 alkyl group; a C2-C60 alkenyl group; a C2-C60 alkynyl group; a C1-C60 alkoxy group; a C3-C60 carbocyclic group or a C1-C60 heterocyclic group, each unsubstituted or substituted with deuterium, —F, a cyano group, a C1-C60 alkyl group, a C1-C60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof; a C7-C60 aryl alkyl group; or a C2-C60 heteroaryl alkyl group.
The term “hetero atom,” as used herein, refers to any atom other than a carbon atom. Examples of the heteroatom include O, S, N, P, Si, B, Ge, Se, or any combination thereof.
The term “the third-row transition metal,” as used herein, includes hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), gold (Au), and the like.
“Ph,” as used herein, refers to a phenyl group, “Me,” as used herein, refers to a methyl group, “Et,” as used herein, refers to an ethyl group, “tert-Bu” or “But,” as used herein, refers to a tert-butyl group, and “OMe,” as used herein, refers to a methoxy group.
The term “biphenyl group,” as used herein, refers to “a phenyl group substituted with a phenyl group.” In other words, the “biphenyl group” is a substituted phenyl group having a C6-C60 aryl group as a substituent.
The term “terphenyl group,” as used herein, refers to “a phenyl group substituted with a biphenyl group”. The “terphenyl group” is a substituted phenyl group having, as a substituent, a C6-C60 aryl group substituted with a C6-C60 aryl group.
* and *’, as used herein, unless defined otherwise, each refer to a binding site to a neighboring atom in a corresponding formula or moiety.
Hereinafter, compounds according to embodiments and light-emitting devices according to embodiments will be described in more detail with reference to the following synthesis examples and examples. The wording “B was used instead of A” used in describing Synthesis Examples means that an identical molar equivalent of B was used in place of A.
2-chlorobenzimidazole (1.0 eq) and 2-bromoaniline (1.1 eq) were dissolved in N-methyl-2-pyrrolidine (2.0 M) at room temperature, and then methanesulfonic acid (1.1 eq) was slowly added thereto for 0.5 hours. The resultant reaction mixture was heated at 100° C., and then stirred until a starting material disappeared completely. The resultant reaction mixture was cooled at room temperature, diluted with distilled water, and then neutralized with a 30 w-% sodium hydroxide aqueous solution. The product precipitated as a solid was obtained through filtration, washed with water, and then dried under vacuum, to thereby obtain Intermediate Compound 1-A. (yield: 90%)
Intermediate Compound 1-A (1.0 eq), cesium carbonate (1.3 eq), and copper(II) bromide (2.0 mol%) were dissolved in dimethyl formamide (1.0 M), and then stirred for 24 hours at 130° C. The resultant reaction mixture was cooled at room temperature and then diluted with water. The product precipitated as a solid was obtained through filtration, washed with water, and then dried in a vacuum condition, to thereby obtain Intermediate Compound 1-B. (yield: 93%)
Intermediate Compound 1-B (1.0 eq), 1-bromo-3-iodobenzene (1.5 eq), Pd2(dba)3 (0.2 eq), 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (Sphos) (0.4 eq), and K3PO4 (2.0 eq) were dissolved in toluene (0.5 M), and then stirred for 12 hours at 120° C. The resultant reaction mixture was cooled at room temperature, and then subjected to an extraction process three times using water to obtain an organic layer. The organic layer thus obtained was dried using magnesium sulfate and concentrated, and column chromatography was used to synthesize Intermediate Compound 1-C (yield: 75%).
Intermediate Compound 1-C (1.0 eq), 1-D (1.2 eq), copper(I) iodide (0.01 eq), K2CO3 (2.0 eq), and L-Proline (0.02 eq) were dissolved in DMSO (0.1 M), and then stirred for 24 hours at 130° C. The resultant reaction mixture was cooled at room temperature, and then subjected to an extraction process three times using water to obtain an organic layer. The organic layer thus obtained was dried by using magnesium sulfate and concentrated, and column chromatography was used to obtain Intermediate Compound 1-E (yield: 68%).
Intermediate Compound 1-E (1.0 eq) and K2PtCl2 (1.2 eq) were dissolved in 2-ethoxyethanol (0.05 M) and then stirred for 24 hours at 120° C. The resultant reaction mixture was cooled at room temperature, and an extraction process was performed thereon three times by using dichloromethane and water, to thereby obtain an organic layer. The organic layer thus obtained was dried by using magnesium sulfate and concentrated, and column chromatography was used to obtain Compound 1 (yield: 24%).
Intermediate Compound 2-E (yield: 66%) was synthesized in substantially the same manner as used to synthesize Intermediate Compound 1-E, except that Intermediate Compound 2-D was used instead of Intermediate Compound 1-D.
Compound 2 (yield: 21%) was synthesized in substantially the same manner as used to synthesize Compound 1, except that Intermediate Compound 2-E was used instead of Intermediate Compound 1-E.
Intermediate Compound 3-D (yield: 53%) was synthesized in substantially the same manner as used to synthesize Intermediate Compound 1-C, except that 3-bromophenol was used instead of 1-bromo-3-iodobenzene.
Intermediate Compound 3-E (yield: 62%) was synthesized in substantially the same manner as used to synthesize Intermediate Compound 1-E, except that Intermediate Compound 3-D was used instead of Intermediate Compound 1-D.
Compound 51 (yield: 31%) was synthesized in substantially the same manner as used to synthesize Compound 1, except that Intermediate Compound 3-E was used instead of Intermediate Compound 1-E.
Intermediate Compound 4-C (yield: 67%) was synthesized in substantially the same manner as used to synthesize Intermediate Compound 1-C, except that 1,3-dibromo-5-(tert-butyl)benzene was used instead of 1-bromo-3-iodobenzene.
Intermediate Compound 4-E (yield: 70%) was synthesized in substantially the same manner as used to synthesize Intermediate Compound 1-E, except that Intermediate Compound 4-C was used instead of Intermediate Compound 1-C, and Intermediate Compound 3-D was used instead of Intermediate Compound 1-D.
Compound 52 (yield: 26%) was synthesized in substantially the same manner as used to synthesize Compound 1, except that Intermediate Compound 4-E was used instead of Intermediate Compound 1-E.
LUMO and HOMO values of compounds of Synthesis Examples were measured using methods described in Table 2 below, and by using the Density Functional Theory (DFT) method of the Gaussian 09 program (where the structure optimization is performed at the level of the B3LYP hybrid functional, and 6-311 G(d,p) basis set), T1, dipole, and MLCT values of Compounds of Synthesis Examples were calculated. The results are shown in Table 3 below.
3MLCT (%)
As an anode, a 15 Ω/cm2 (1200 Å) ITO glass substrate (available from Corning Co., Ltd) was cut to a size of 50 mm x 50 mm x 0.7 mm, sonicated in isopropyl alcohol and pure water for 5 minutes in each solvent, and cleaned by irradiation of ultraviolet rays and exposure of ozone thereto for 30 minutes, and the glass substrate was loaded onto a vacuum deposition apparatus.
2-TNATA, which is a commercially available compound, was vacuum-deposited on the substrate to form a hole injection layer having a thickness of 600 Å, and then, 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (hereinafter, referred to as NPB) as a hole transport compound was vacuum-deposited thereon to form a hole transport layer having a thickness of 300 Å.
Compound 1 (first compound), ETH2 (second compound), HTH29 (third compound) were vacuum-deposited on the hole transport layer to form an emission layer having a thickness of 400 Å. In this regard, an amount of Compound 1 is 10 wt% based on a total weight (100 wt%) of the emission layer, and a weight ratio of Compound ETH2 to Compound HTH29 was adjusted to 3 : 7.
Next, ETH2 was vacuum-deposited thereon to form a hole blocking layer having a thickness of 50 Å, Alq3 was deposited on the hole blocking layer to form an electron transport layer having a thickness of 300 Å, LiF as an alkali metal halide was deposited on the electron transport layer to form an electron injection layer having a thickness of 10 Å, and Al was vacuum-deposited thereon to form a cathode having a thickness of 3,000 Å, thereby completing manufacture of an organic electroluminescent device.
Organic electroluminescent devices were manufactured in substantially the same manner as in Example 1, except that, in forming the emission layer, the first compound shown in Table 4 was used instead of Compound 1.
Driving voltage (V), luminescence efficiency (cd/A), maximum emission wavelength (nm), and device lifespan (T90) of organic electroluminescent devices according to Examples 1 to 4 and Comparative Examples 1 and 2 were each measured using a Keithley MU 236 and a luminance meter PR650, and the results are shown in Table 4 below. In Table 4, the driving voltage and the luminescence efficiency were driving voltage and luminescence efficiency at 10 mA/cm of current density, and the device lifespan (T90) is a measure of the time taken when the luminance reaches 90% of the initial luminance of 1,000 cd/m2.
Referring to Table 4, it can be seen that the organic electroluminescent devices according to Examples 1 to 4 had improved luminescence efficiency and device lifespan, as compared to the organic electroluminescent devices according to Comparative Examples 1 and 2.
Organic light-emitting devices were manufactured in substantially the same manner as in Example 1, except that, in forming the emission layer, Compound 1 (first compound), Compound ETH2 (second compound), Compound HTH41 (third compound), and Compound DFD1 (fourth compound), which are shown in Table 5, were used instead of Compound 1 (first compound), Compound ETH2 (second compound), and Compound HTH29 (third compound). In this regard, an amount of the first compound was 10 wt% based on the total weight (100 wt%) of the emission layer, an amount of Compound DFD1 is 0.5 wt% based on the total weight (100 wt%) of the emission layer, and a weight ratio of Compound ETH2 to Compound HTH41 was adjusted to 3 : 7.
Driving voltage (V), luminescence efficiency (cd/A), maximum emission wavelength (nm), and device lifespan (T90) of organic electroluminescent devices according to Examples 5 and 6 and Comparative Example 3 were each measured using a Keithley MU 236 and a luminance meter PR650, and the results are each shown in Table 5. In Table 5, the driving voltage and the luminescence efficiency were driving voltage and luminescence efficiency at 10 mA/cm of current density, and the device lifespan (T90) is a measure of the time taken when the luminance reaches 90% of the initial luminance of 1,000 cd/m2.
Referring to Table 5, it can be seen that the organic electroluminescent devices according to Examples 5 and 6 exhibited high luminescence efficiency and color conversion efficiency in a blue emission wavelength region and had excellent device lifespan, as compared to the organic electroluminescent device according to Comparative Example 3.
A light-emitting device having high efficiency and long lifespan and a high-quality electronic apparatus including the same may be manufactured by using the organometallic compound.
It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the following claims, and equivalents thereof.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2021-0152569 | Nov 2021 | KR | national |
