阅读说明：本技术 半导体材料、其制备方法以及电子器件 (Semiconductor material, method for producing same, and electronic device ) 是由 弗朗索瓦·卡尔迪纳利 杰罗姆·加尼耶 卡斯滕·罗特 本杰明·舒尔策 于 2018-12-20 设计创作，主要内容包括：本发明涉及一种半导体材料、包含所述半导体材料的电子器件以及制备所述半导体材料的方法,所述半导体材料包含：(i)至少一种包含二价金属的金属络合物或金属盐；和(ii)至少一种包含二烷基氧化膦基团的基质化合物。(The present invention relates to a semiconductor material, an electronic device comprising said semiconductor material and a method of preparing said semiconductor material, said semiconductor material comprising: (i) at least one metal complex or metal salt comprising a divalent metal; and (ii) at least one matrix compound comprising dialkylphosphine oxide groups.)

1. A semiconductor material, the semiconductor material comprising:

(i) at least one metal complex or metal salt comprising a divalent metal; and

(ii) at least one matrix compound comprising dialkylphosphine oxide groups.

2. The semiconducting material of claim 1, wherein the metal complex or metal salt is a borate complex or borate comprising at least one borate anion.

3. The semiconducting material of claim 1 or 2, wherein the divalent metal ion is selected from the group consisting of: ca²⁺、Sr²⁺And Mg^{2 +}。

4. The semiconducting material of any of claims 2 or 3, wherein the metal complex or metal salt has the following formula (I):

wherein M is a divalent metal ion, A¹-A⁴Each independently selected from: H. substituted or unsubstituted C₆-C₂₀Aryl and substituted or unsubstituted C₂-C₂₀A heteroaryl group.

5. The semiconductor material of claim 4, wherein A¹To A⁴At least one or at least two of which are nitrogen-containing heteroaryl groups.

6. Semiconducting material according to claim 5, wherein the nitrogen-containing heteroaryl is pyrazolyl.

7. Semiconducting material according to any of the preceding claims, wherein the host compound has the following formula (1):

wherein R is¹And R²Each independently selected from C₁To C₁₆An alkyl group;

Ar¹is selected from C₆To C₁₄Arylidene radicals or C₃To C₁₂A heteroaromatic subunit;

Ar²independently selected from C₁₄To C₄₀Arylidene radicals or C₈To C₄₀A heteroaromatic subunit;

R³independently selected from H, C₁To C₁₂Alkyl or C₁₀To C₂₀An aryl group;

wherein Ar is¹、Ar²And R³Each of which may each independently be unsubstituted or substituted by at least one C₁To C₁₂Alkyl group substitution;

n is 0 or 1; and is

In the case where n is 0, m is 1; and in the case where n is 1, m is 1 or 2.

8. The semiconductor material of claim 7, wherein Ar¹Selected from: a benzylidene, biphenylidene, naphthylidene, fluorenylidene, pyridylidene, quinolinylidene, and pyrimidylidene group.

9. The semiconductor material of claim 7 or 8, wherein Ar²Selected from: naphthalene subunit, fluorene subunit, anthracene subunit, pyrene subunit, phenanthrene subunit, carbazole subunit, benzo [ c ]]Acridinylidene, dibenzo [ c, h ]]Acridinylidene, dibenzo [ a, j ]]Acridinium, or selected from the following formulae (IVa) to (IVm):

10. semiconducting material according to any of the preceding claims, wherein the matrix compound is selected from one of the following compounds a to g:

11. semiconducting material according to any of the preceding claims, wherein the matrix compound is an electron transporting matrix compound.

12. An electronic device comprising a semiconductor layer made of the semiconductor material according to any one of the preceding claims.

13. The electronic device of claim 12, wherein the electronic device is an organic electronic device.

14. The electronic device of any one of claims 12 or 13, wherein the organic semiconductor layer is an electron transport layer.

15. A method for preparing a semiconducting material according to any of claims 1to 11, the method comprising the steps of:

(i) co-evaporating the divalent metal salt or divalent metal complex with the matrix material; and

(ii) co-depositing the divalent metal salt or divalent metal complex with the matrix compound.

Technical Field

The present invention relates to a semiconductor material, a method for preparing the same, and an electronic device including a semiconductor layer made of the semiconductor material.

Background

An Organic Light Emitting Diode (OLED) as a self-light emitting device has a wide viewing angle, excellent contrast, fast response, high brightness, excellent driving voltage characteristics, and color reproduction. A typical OLED includes an anode, a Hole Transport Layer (HTL), an emission layer (EML), an Electron Transport Layer (ETL), and a cathode, which are sequentially stacked on a substrate. In this regard, the HTL, EML, and ETL are thin films formed of organic and/or organometallic compounds.

When a voltage is applied to the anode and the cathode, holes injected from the anode electrode move to the EML through the HTL, and electrons injected from the cathode electrode move to the EML through the ETL. The holes and electrons recombine in the EML to generate excitons. When the excitons drop from an excited state to a ground state, light is emitted. The injection and flow of holes and electrons should be balanced so that the OLED having the above structure has excellent efficiency.

Borate complexes for use in organic electronic devices are known in the prior art, for example from european patent application EP 2786433 a 1.

Dialkyl phosphine oxide compounds are disclosed, for example, in WO 2017/089399 as suitable compounds for use in organic semiconductor layers, in particular as electron host materials for organic electronic devices such as OLEDs.

However, there is still a need to further improve the performance of organic electronic devices.

It is therefore an object of the present invention to provide novel compounds for use in semiconductor layers of organic electronic devices which overcome the disadvantages of the prior art, in particular such compounds are suitable for improving the properties of organic electronic devices. In particular, it is an object of the present invention to provide semiconducting materials which exhibit advantageous properties in organic electronic devices, in particular an improved stability of the operating voltage at high temperatures.

Disclosure of Invention

This object is achieved by a semiconductor material comprising: (i) at least one metal complex or metal salt comprising a divalent metal; and (ii) at least one matrix compound comprising dialkylphosphine oxide groups.

The inventors have surprisingly found that the combination of the two options of the present invention ((i) a metal complex or metal salt comprising a divalent metal and (ii) a matrix compound comprising at least one dialkylphosphine oxide group) results in an improved semiconductor material with improved stability of the operating voltage at high temperatures compared to corresponding materials known in the art.

In the semiconductor material, the metal complex or metal salt may be a borate complex or borate comprising at least one borate anion. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the metal complex or metal salt may be composed of one divalent metal cation and two monovalent anions. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the metal may form at least one ring, preferably a five-, six-or seven-membered ring, with at least one anion. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the metal complex or metal salt may comprise two borate anions, preferably two borate anions which may be the same. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the at least one monovalent anion may comprise at least one heterocyclic group. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the heterocyclic group may be a heteroaryl group, preferably C₂-C₃₀A heteroaryl group. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the heterocyclic group may comprise one or more heteroatoms independently selected from: n, O and S. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the heterocyclic group may comprise a five-membered heterocyclic ring. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the heterocyclic group may comprise an azole or oxadiazole ring. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the heterocyclic group may be a1, 2-oxadiazole group. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the anion may comprise at least two heterocyclic groups. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the divalent metal ion may be selected from: ca²⁺、Sr²⁺And Mg²⁺. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the metal complex or metal salt may have the following formula (I):

wherein M may be a divalent metal ion, A¹-A⁴Each may be independently selected from: H. substituted or unsubstituted C₆-C₂₀Aryl and substituted or unsubstituted C₂-C₂₀A heteroaryl group. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, A¹To A⁴At least one, or at least two, or at least three, or four of the groups may be nitrogen-containing heteroaryl. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, each nitrogen-containing heteroaryl group may be bonded to the central boron atom through a B-N bond. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconducting material, the nitrogen-containing heteroaryl group may be pyrazolyl. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the host compound may have the following formula (1).

Wherein R is¹And R²May each be independently selected from C₁To C₁₆An alkyl group; ar (Ar)¹May be selected from C₆To C₁₄Arylidene radicals or C₃To C₁₂A heteroaromatic subunit; ar (Ar)²Can be independently selected from C₁₄To C₄₀Arylidene radicals or C₈To C₄₀A heteroaromatic subunit; r³Can be independently selected from H, C₁To C₁₂Alkyl or C₁₀To C₂₀An aryl group; wherein Ar is¹、Ar²And R³Each of which may each independently be unsubstituted or substituted by at least one C₁To C₁₂Alkyl group substitution; n may be 0 or 1; and in the case where n is 0, m may be 1; and m may be 1 or 2 in the case where n is 1. In specific cases, R¹And R²May be the same or connected to each other to form a ring. In another particular case, R¹And R²Each may be methyl.

In these ways, a fine tuning of the electronic structure of the semiconductor material composition of the invention is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, Ar¹May be selected from: a benzylidene, biphenylidene, naphthylidene, fluorenylidene, pyridylidene, quinolinylidene, and pyrimidylidene group. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, Ar²May be selected from: naphthalene subunit, fluorene subunit, anthracene subunit, pyrene subunit, phenanthrene subunit, carbazole subunit, benzo [ c ]]Acridinium, diBenzo [ c, h ]]Acridinylidene, dibenzo [ a, j ]]Acridinium, or selected from the following formulae (IVa) to (IVm):

in this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, Ar²May be selected from: anthracenylene, pyrene, phenanthrylene, benzo [ c]Acridinylidene, dibenzo [ c, h ]]Acridinylidene and dibenzo [ a, j ]]An acridinium subunit. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, R³May be selected from: H. phenyl, biphenyl, terphenyl, fluorenyl, naphthyl, phenanthryl, pyrenyl, carbazolyl, dibenzofuranyl, or dinaphthofuranyl. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the phosphine oxide compound may be selected from one of the following compounds a to g.

In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the host compound may be an electron-transporting host compound. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

In the semiconductor material, the borate complex and the matrix compound may be present in the form of a homogeneous mixture. In this way, a fine tuning of the electronic structure of the inventive semiconductor material composition is achieved to improve its usability in the semiconductor layers of electronic devices, in particular in the electron transport layers thereof.

The object is also achieved by an electronic device comprising a semiconductor layer made of the semiconductor material according to the invention.

The electronic device may be an organic electronic device.

The organic device may be an organic light emitting diode, an organic solar cell or an organic field effect transistor.

In an electronic device, the organic semiconductor layer may be an electron transport layer.

Finally, the object is achieved by a method for producing a semiconductor material according to the invention, comprising the following steps: (i) co-evaporating a divalent metal salt or a divalent metal complex with a matrix material; and (ii) co-depositing a divalent metal salt or a divalent metal complex with the matrix compound.

In the methods of the present invention, the "substrate" can be any suitable adjacent layer. For example, in the case where the borate complex is contained in the electron transport layer, the substrate may be an electron injection layer. Also, in the case where the borate complex of the present invention is contained in the electron injection layer, the substrate may be an electrode.

Additional layer

According to the invention, the organic electronic device may comprise further layers in addition to the layers already mentioned above. Exemplary embodiments of the various layers are described below:

substrate

The substrate may be any substrate commonly used in the manufacture of electronic devices such as organic light emitting diodes. If light is to be emitted through the substrate, the substrate should be a transparent or translucent material, such as a glass substrate or a transparent plastic substrate. If light is to be emitted through the top surface, the substrate may be either a transparent or an opaque material, such as a glass substrate, a plastic substrate, a metal substrate, or a silicon substrate.

Anode electrode

The first electrode or the second electrode may be an anode electrode. The anode electrode may be formed by depositing or sputtering a material for forming the anode electrode. The material used to form the anode electrode may be a high work function material to facilitate hole injection. The anode material may also be selected from low work function materials (i.e., aluminum). The anode electrode may be a transparent or reflective electrode. Transparent conductive oxides such as Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), tin dioxide (SnO) may be used₂) Zinc aluminum oxide (AlZnO) and zinc oxide (ZnO) to form the anode electrode. The anode electrode may also be formed using a metal or a metal alloy, typically silver (Ag), gold (Au).

Hole injection layer

The Hole Injection Layer (HIL) may be formed on the anode electrode by vacuum deposition, spin coating, printing, casting, slot die coating, Langmuir-blodgett (lb) deposition, or the like. When forming the HIL using vacuum deposition, the deposition conditions may vary depending on the compound used to form the HIL and the desired structural and thermal properties of the HIL. In general, however, the conditions for vacuum deposition may include a deposition temperature of 100 ℃ to 500 ℃,10 ℃^-8To 10^-3A pressure of Torr (1Torr equals 133.322Pa) and a deposition rate of 0.1 to 10 nm/sec.

When the HIL is formed using spin coating or printing, the coating conditions may vary depending on the compound used to form the HIL and the desired structure and thermal properties of the HIL. For example, the coating conditions may include a coating speed of about 2000rpm to about 5000rpm and a heat treatment temperature of about 80 ℃ to about 200 ℃. After the coating is performed, the solvent is removed by heat treatment.

The HIL may be formed from any compound commonly used to form HILs. Examples of compounds that can be used to form the HIL include phthalocyanine compounds such as copper phthalocyanine (CuPc), 4' -tris (3-methylphenylphenylamino) triphenylamine (m-MTDATA), TDATA, 2T-NATA, polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA), poly (3, 4-ethylenedioxythiophene)/poly (4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphorsulfonic acid (Pani/CSA), and polyaniline/poly (4-styrenesulfonate) (PANI/PSS).

The HIL may be a pure layer of a p-type dopant, and the p-type dopant may be selected from: tetrafluoro-tetracyanoquinodimethane (F4TCNQ), 2'- (perfluoronaphthalene-2, 6-diyl) dipropylenedinitrile or 2,2',2 "- (cyclopropane-1, 2, 3-triylidene) tris (2- (p-cyanotetrafluorophenyl) acetonitrile), but are not limited thereto. The HIL may be selected from hole-transporting host compounds doped with a p-type dopant. Typical examples of known doped hole transport materials are: a copper phthalocyanine (CuPc) doped with tetrafluoro-tetracyanoquinodimethane (F4TCNQ), said copper phthalocyanine (CuPc) having a HOMO energy level of about-5.2 eV and said tetrafluoro-tetracyanoquinodimethane (F4TCNQ) having a LUMO energy level of about-5.2 eV; zinc phthalocyanine (ZnPc) doped with F4TCNQ (HOMO ═ 5.2 eV); α -NPD (N, N '-bis (naphthalen-1-yl) -N, N' -bis (phenyl) -benzidine) doped with F4 TCNQ; α -NPD doped with 2,2' - (perfluoronaphthalene-2, 6-diyl) dipropionitrile; α -NPD doped with 2,2' - (cyclopropane-1, 2, 3-triylidene) tris (2- (p-cyanotetrafluorophenyl) acetonitrile). The dopant concentration may be selected from 1to 20 wt%, more preferably 3 to 10 wt%.

The thickness of the HIL can be in the range of about 1nm to about 100nm, and for example, in the range of about 1nm to about 25 nm. When the thickness of the HIL is within this range, the HIL may have excellent hole injection characteristics without causing substantial damage to a driving voltage.

Hole transport layer

The Hole Transport Layer (HTL) may be formed on the HIL by vacuum deposition, spin coating, slot die coating, printing, casting, Langmuir-blodgett (lb) deposition, or the like. When the HTL is formed by vacuum deposition or spin coating, the conditions of deposition and coating may be similar to those of forming the HIL. However, the conditions of vacuum or solution deposition may vary depending on the compound used to form the HTL.

The HTL may be formed from any of the compounds commonly used to form HTLs. Compounds that may be suitably used are disclosed, for example, in Yasuhiko Shirota and Hiroshi Kageyama, chem.Rev.2007,107,953-1010, which are incorporated herein by reference. Examples of compounds that can be used to form the HTL are: carbazole derivatives such as N-phenylcarbazole or polyvinylcarbazole; benzidine derivatives such as N, N ' -bis (3-methylphenyl) -N, N ' -diphenyl- [1, 1-biphenyl ] -4,4' -diamine (TPD) or N, N ' -bis (naphthalen-1-yl) -N, N ' -diphenylbenzidine (α -NPD); and triphenylamine-based compounds such as 4,4',4 ″ -tris (N-carbazolyl) triphenylamine (TCTA). In these compounds, TCTA can transport holes and inhibit exciton diffusion into the EML.

The thickness of the HTL may range from about 5nm to about 250nm, preferably from about 10nm to about 200nm, further from about 20nm to about 190nm, further from about 40nm to about 180nm, further from about 60nm to about 170nm, further from about 80nm to about 160nm, further from about 100nm to about 160nm, further from about 120nm to about 140 nm. The preferred thickness of the HTL may be 170nm to 200 nm.

When the thickness of the HTL is within this range, the HTL may have excellent hole transport characteristics without causing substantial damage to the driving voltage.

Electron blocking layer

The Electron Blocking Layer (EBL) functions to prevent electrons from being transferred from the light emitting layer to the hole transport layer, thereby confining the electrons to the light emitting layer. Thereby, efficiency, operating voltage and/or lifetime are improved. Typically, the electron blocking layer comprises a triarylamine compound. The LUMO level of the triarylamine compound is closer to the vacuum level than the LUMO level of the hole transport layer. The electron blocking layer may have a HOMO level that is further from the vacuum level than the HOMO level of the hole transport layer. The thickness of the electron blocking layer can be chosen between 2 and 20 nm.

The electron blocking layer may include a compound (Z) of the following formula Z.

In formula Z, CY1 and CY2 are the same as or different from each other and each independently represent a benzene ring or a naphthalene ring, B¹To B³Are identical or different from each other and are each independently selected from: hydrogen; a substituted or unsubstituted aryl group having 6 to 30 carbon atoms; and hasA substituted or unsubstituted heteroaryl group of 5 to 30 carbon atoms, B⁴Selected from: a substituted or unsubstituted phenyl group; a substituted or unsubstituted biphenyl group; a substituted or unsubstituted terphenyl group; a substituted or unsubstituted terphenyl group; and a substituted or unsubstituted heteroaryl group having 5 to 30 carbon atoms, L is a substituted or unsubstituted arylidene group having 6 to 30 carbon atoms.

If the electron blocking layer has a high triplet energy level, it can also be described as a triplet-controlling layer.

If a phosphorescent green or blue light-emitting layer is used, the function of the triplet-controlling layer is to reduce quenching of the triplet state. Thereby, higher light emission efficiency from the phosphorescent light emitting layer can be achieved. The triplet-controlling layer is selected from triarylamine compounds having triplet energy levels higher than the triplet energy levels of the phosphorescent emitters in the adjacent light-emitting layer. Suitable compounds for the triplet-controlling layer, in particular triarylamine compounds, are described in EP 2722908 a 1.

Luminous layer (EML)

The EML may be formed on the HTL by vacuum deposition, spin coating, slot die coating, printing, casting, LB deposition, or the like. When the EML is formed using vacuum deposition or spin coating, the conditions of deposition and coating may be similar to those of forming the HIL. However, the conditions of deposition and coating may vary with the compound used to form the EML.

The emissive layer (EML) may be formed from a combination of a host and an emitter dopant. Examples of hosts are Alq3, 4' -N, N ' -dicarbazole-biphenyl (CBP), poly (N-vinylcarbazole) (PVK), 9, 10-bis (naphthalen-2-yl) Anthracene (ADN), 4',4 ″ -tris (carbazol-9-yl) -triphenylamine (TCTA), 1,3, 5-tris (N-phenylbenzimidazol-2-yl) benzene (TPBI), 3-tert-butyl-9, 10-bis-2-naphthoanthracene (TBADN), Distyrylarylene (DSA), bis (2- (2-hydroxyphenyl) benzothiazole) zinc (zn (btz)₂) G3 below, "AND", compound 1 below AND compound 2 below.

The luminophore dopant may be a phosphorescent or fluorescent luminophore. Phosphorescent emitters and emitters that emit via a Thermally Activated Delayed Fluorescence (TADF) mechanism may be preferred due to their higher efficiency. The luminophores may be small molecules or polymers.

Examples of red emitter dopants are PtOEP, Ir (piq)₃And Btp₂Ir (acac), but is not limited thereto. These compounds are phosphorescent emitters, however, fluorescent red emitter dopants may also be used.

Examples of phosphorescent green emitter dopants are the Ir (ppy) s shown below₃(ppy. phenylpyridine), Ir (ppy)₂(acac)、Ir(mpyp)₃. Compound 3 is an example of a fluorescent green emitter and the structure is shown below.

Compound 3

An example of a phosphorescent blue emitter dopant is F₂Irpic、(F₂ppy)₂Ir (tmd) and Ir (dfppz)₃And the structure of the fluorene is shown as follows. 4,4' -bis (4-diphenylaminostyryl) biphenyl (DPAVBi), 2,5,8, 11-tetra-tert-butylperylene (TBPe) and compound 4 below are examples of fluorescent blue emitter dopants.

The amount of the emitter dopant may be in the range of about 0.01 to about 50 parts by weight based on 100 parts by weight of the host. Alternatively, the light emitting layer may be composed of a light emitting polymer. The EML may have a thickness of about 10nm to about 100nm, for example about 20nm to about 60 nm. When the thickness of the EML is within this range, the EML may have excellent light emission without causing substantial damage to the driving voltage.

Hole Blocking Layer (HBL)

A Hole Blocking Layer (HBL) may be formed on the EML by using vacuum deposition, spin coating, slot die coating, printing, casting, LB deposition, etc. to prevent holes from diffusing into the ETL. When the EML includes a phosphorescent dopant, the HBL may also have a triplet exciton blocking function.

When the HBL is formed using vacuum deposition or spin coating, the conditions of deposition and coating may be similar to those used to form the HIL. However, the conditions of deposition and coating may vary depending on the compound used to form the HBL. Any compound commonly used to form HBLs may be used. Examples of compounds useful for the formation of HBL includeOxadiazole derivatives, triazole derivatives and phenanthroline derivatives.

The thickness of the HBL may be in the range of about 5nm to about 100nm, such as about 10nm to about 30 nm. When the thickness of the HBL is within this range, the HBL may have excellent hole blocking properties without causing substantial damage to the driving voltage.

Electronic Transmission Layer (ETL)

The OLED according to the invention may contain an Electron Transport Layer (ETL). According to the invention, the electron transport layer may be an organic semiconductor layer of the invention comprising a semiconducting material of the invention, i.e. an inventive combination of a metal complex or metal salt as defined above and a dialkylphosphine oxide matrix compound.

According to various embodiments, the OLED may comprise an electron transport layer or an electron transport layer stack structure comprising at least a first electron transport layer and at least a second electron transport layer.

By appropriately adjusting the energy level of a specific layer of the ETL, the injection and transport of electrons can be controlled, and holes can be effectively blocked. Thus, the OLED may have a long lifetime.

The electron transport layer of the organic electronic device may comprise a semiconducting material as defined above as the organic Electron Transporting Matrix (ETM) material. In addition to the combination of the metal complex or metal salt and the dialkylphosphine oxide matrix compound, the electron transport layer may further comprise additional ETM materials known in the art. Also, the electron transport layer may comprise a combination of a metal complex or metal salt and a dialkylphosphine oxide matrix compound as the sole electron transport matrix material. In the case where the organic electronic device of the present invention comprises more than one electron transport layer, the combination of the metal complex or metal salt and the dialkylphosphine oxide matrix compound may be contained in only one electron transport layer, in more than one electron transport layer, or in all electron transport layers. According to the present invention, the electron transport layer may comprise at least one additive as defined below in addition to the ETM material. In addition, the electron transport layer may comprise one or more n-type dopants. The additive may be an n-type dopant. The additive may be an alkali metal, an alkali metal compound, an alkaline earth metal compound, a transition metal compound, or a rare earth metal. In another embodiment, the metal may be one selected from the group consisting of: li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, La, Ce, Sm, Eu, Tb, Dy and Yb. In another embodiment, the n-type dopant may be one selected from the group consisting of: cs, K, Rb, Mg, Na, Ca, Sr, Eu and Yb. In one embodiment, the alkali metal compound may be lithium 8-hydroxyquinoline (LiQ), lithium tetrakis (1H-pyrazol-1-yl) borate, or lithium 2- (diphenylphosphoryl) phenoxide. Suitable compounds for ETM (which may be used in addition to the compounds of the present invention represented by the general formula (I) as defined above) are not particularly limited. In one embodiment, the electron transport matrix compound is comprised of covalently bonded atoms. Preferably, the electron transport matrix compound comprises a conjugated system of at least 6, more preferably at least 10 delocalized electrons. In one embodiment, the conjugated system of delocalized electrons may be comprised in an aromatic or heteroaromatic moiety, as disclosed for example in documents EP 1970371 a1 or WO 2013/079217a 1.

Electron Injection Layer (EIL)

An optional EIL (which may facilitate electron injection from the cathode) may be formed on the ETL, preferably directly on the electron transport layer.According to the present invention, the EIL may be a semiconductor layer comprising a combination of a metal complex or metal salt and a dialkylphosphine oxide matrix compound. If the combination of the metal complex or metal salt and the dialkylphosphine oxide matrix compound is not comprised in the EIL, but in another layer, such as the ETL, the EIL material may be selected from materials known in the art for the respective use. Examples of materials forming the EIL include lithium 8-hydroxyquinoline (LiQ), LiF, NaCl, CsF, Li, which are known in the art₂O, BaO, Ca, Ba, Yb, Mg. The deposition and coating conditions for forming the EIL are similar to those for forming the HIL, but the deposition and coating conditions may vary depending on the material used to form the EIL.

The EIL may have a thickness in the range of about 0.1nm to about 10nm, for example in the range of about 0.5nm to about 9 nm. When the thickness of the EIL is within this range, the EIL may have satisfactory electron injection properties without causing substantial damage to the driving voltage.

Cathode electrode

If an EIL is present, a cathode electrode is formed on the EIL. The cathode electrode may be formed of a metal, an alloy, a conductive compound, or a mixture thereof. The cathode electrode may have a low work function. For example, the cathode electrode may be formed of lithium (Li), magnesium (Mg), aluminum (Al) -lithium (Li), calcium (Ca), barium (Ba), ytterbium (Yb), magnesium (Mg) -indium (In), magnesium (Mg) -silver (Ag), or the like. Alternatively, the cathode electrode may be formed of a transparent conductive oxide such as ITO or IZO.

The thickness of the cathode electrode may be in the range of about 5nm to about 1000nm, for example in the range of about 10nm to about 100 nm. When the thickness of the cathode electrode is in the range of about 5nm to about 50nm, the cathode electrode may be transparent or translucent even if formed of a metal or metal alloy.

It should be understood that the cathode electrode is not part of the electron injection layer or the electron transport layer.

Charge generation layer/hole generation layer

The Charge Generation Layer (CGL) may be composed of a double layer.

In general, the charge generation layer is a pn junction connecting an n-type charge generation layer (electron generation layer) and a hole generation layer. The n-side of the pn-junction generates electrons and injects them into the layer adjacent in the direction of the anode. Similarly, holes are generated on the p-side of the p-n junction and injected into the adjacent layers in the cathode direction.

Charge generating layers are used in tandem devices, for example in tandem OLEDs comprising two or more light emitting layers between two electrodes. In a tandem OLED comprising two light emitting layers, an n-type charge generation layer provides electrons to a first light emitting layer disposed near the anode, and a hole generation layer provides holes to a second light emitting layer disposed between the first light emitting layer and the cathode.

Suitable host materials for the hole generating layer may be materials conventionally used as hole injecting and/or hole transporting host materials. Also, the p-type dopant for the hole generation layer may employ a conventional material. For example, the p-type dopant may be one selected from the group consisting of: tetrafluoro-7, 7,8, 8-tetracyanoquinodimethane (F4-TCNQ), tetracyanoquinodimethane derivatives, limonene derivatives, iodine, FeCl₃、FeF₃And SbCl₅. In addition, the body may be one selected from the group consisting of: n, N ' -di (naphthalen-1-yl) -N, N-diphenyl benzidine (NPB), N ' -diphenyl-N, N ' -bis (3-methylphenyl) -1, 1-biphenyl-4, 4' -diamine (TPD), and N, N ' -tetranaphthyl benzidine (TNB).

The n-type charge generation layer may be a layer of a pure n-type dopant, such as an electropositive metal, or may be composed of an organic host material doped with an n-type dopant. According to the present invention, the n-type charge generation layer (═ electron generation layer) may be a layer comprising a combination of a metal complex or metal salt and a dialkylphosphine oxide base compound. In the case where the combination of the metal complex or metal salt and the dialkylphosphine oxide base compound is not contained in the electron generation layer but contained in another layer such as an electron transport layer or an electron injection layer, for this purpose, the material of the n-type charge generation layer may be selected from materials well known in the art. In one embodiment, the n-type dopant may be an alkali metal, an alkali metal compound, an alkaline earth metal compound, a transition metal compound, or a rare earth metal. In another embodiment, the metal may be one selected from the group consisting of: li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, La, Ce, Sm, Eu, Tb, Dy and Yb. More specifically, the n-type dopant may be one selected from the group consisting of: cs, K, Rb, Mg, Na, Ca, Sr, Eu and Yb. Suitable matrix materials for the electron generation layer may be materials conventionally used as matrix materials for electron injection or electron transport layers. The matrix material may be, for example, one selected from the group consisting of: triazine compounds, hydroxyquinoline derivatives such as tris (8-hydroxyquinoline) aluminum, benzoxazole derivatives and silole derivatives.

In one embodiment, the n-type charge generation layer may include a compound of the following chemical formula X.

Wherein A is¹To A⁶Each may be hydrogen, halogen atom, nitrile (-CN), nitro (-NO)₂) Sulfonyl (-SO)₂R), sulfoxide (-SOR), sulfonamide (-SO)₂NR), sulfonate (-SO)₃R), trifluoromethyl (-CF)₃) Esters (-COOR), amides (-CONHR or-CONRR'), substituted or unsubstituted straight or branched C₁-C₁₂Alkoxy, substituted or unsubstituted straight or branched C₁-C₁₂Alkyl, substituted or unsubstituted straight or branched C₂-C₁₂Alkenyl groups, substituted or unsubstituted aromatic or non-aromatic heterocycles, substituted or unsubstituted aryl groups, substituted or unsubstituted mono-or di-arylamine groups, substituted or unsubstituted aralkylamine groups, and the like. Here, each of the above R and R' may be a substituted or unsubstituted C₁-C₆₀Alkyl, substituted or unsubstituted aryl, or substituted or unsubstituted 5 to 7 membered heterocyclic ring, and the like.

An example of such an n-type charge generation layer may be a layer comprising CNHAT,

the hole generating layer is disposed on top of the n-type charge generating layer.

Organic Light Emitting Diode (OLED)

The organic electronic device according to the present invention may be an organic light emitting device.

According to an aspect of the present invention, there is provided an Organic Light Emitting Diode (OLED) including: a substrate; an anode formed on the substrate; a hole injection layer, a hole transport layer, a light emitting layer, and a cathode electrode.

According to another aspect of the present invention, there is provided an OLED comprising: a substrate; an anode electrode formed on the substrate; a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, and a cathode electrode.

According to another aspect of the present invention, there is provided an OLED comprising: a substrate; an anode electrode formed on the substrate; a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, and a cathode electrode.

According to another aspect of the present invention, there is provided an OLED comprising: a substrate; an anode electrode formed on the substrate; a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and a cathode electrode.

According to various embodiments of the present invention, OLED layers disposed between the above layers may be provided on a substrate or on a top electrode.

According to one aspect, the OLED may comprise a layer structure in which the substrate is disposed adjacent to an anode electrode disposed adjacent to a first hole injection layer, the first hole injection layer is disposed adjacent to a first hole transport layer, the first hole transport layer is disposed adjacent to a first electron blocking layer, the first electron blocking layer is disposed adjacent to a first light emitting layer, the first light emitting layer is disposed adjacent to a first electron transport layer, the first electron transport layer is disposed adjacent to an n-type charge generation layer, the n-type charge generation layer is disposed adjacent to a hole generation layer, the hole generation layer is disposed adjacent to a second hole transport layer, the second hole transport layer is disposed adjacent to a second electron blocking layer, the second electron blocking layer is disposed adjacent to a second light emitting layer, and an optional electron transport layer and/or an optional injection layer is disposed between the second light emitting layer and a cathode electrode.

For example, the OLED according to fig. 2 may be formed by a method wherein

On a substrate (110), an anode (120), a hole injection layer (130), a hole transport layer (140), an electron blocking layer (145), a light-emitting layer (150), a hole blocking layer (155), an electron transport layer (160), an electron injection layer (180), and a cathode electrode (190) are sequentially formed in this order.

Organic electronic device

The organic electronic device according to the invention comprises an organic semiconductor layer comprising a compound according to formula I.

An organic electronic device according to an embodiment may include a substrate, an anode layer, an organic semiconductor layer including the compound of formula 1, and a cathode layer.

An organic electronic device according to one embodiment comprises: at least one organic semiconductor layer comprising at least one compound of the formula I, at least one anode layer, at least one cathode layer and at least one light-emitting layer, wherein the organic semiconductor layer is preferably arranged between the light-emitting layer and the cathode layer.

An Organic Light Emitting Diode (OLED) according to the present invention may include an anode, a Hole Transport Layer (HTL), an emission layer (EML), an Electron Transport Layer (ETL) including at least one compound of formula 1, and a cathode, which are sequentially stacked on a substrate. In this regard, the HTL, the EML, and the ETL are thin films formed of organic compounds.

The organic electronic device according to an embodiment may be a light emitting device, a thin film transistor, a battery, a display device, or a photovoltaic cell, and is preferably a light emitting device.

According to another aspect of the present invention, there is provided a method of manufacturing an organic electronic device, the method using:

-at least one deposition source, preferably two deposition sources, more preferably at least three deposition sources.

Suitable deposition methods include:

-deposition by vacuum thermal evaporation;

-deposition by solution treatment, preferably selected from spin coating, printing, casting; and/or

Slot die coating.

According to various embodiments of the present invention, there is provided a method using the steps of:

-a first deposition source releasing a compound of formula 1 according to the invention; and

-a second deposition source that releases an alkali metal halide or an alkali metal organic complex, preferably a lithium halide or a lithium organic complex;

the method includes the steps of forming an electron transport layer stack structure; thus for an Organic Light Emitting Diode (OLED):

the first electron transport layer is formed by releasing the compound of formula 1 according to the present invention from the first deposition source and releasing an alkali metal compound, preferably an alkali metal halide or an alkali metal organic complex, preferably a lithium halide or a lithium organic complex, from the second deposition source.

According to various embodiments of the present invention, the method may further include forming a light emitting layer on the anode electrode, and forming at least one layer selected from the group consisting of: forming a hole injection layer, forming a hole transport layer, or forming a hole blocking layer.

According to various embodiments of the present invention, the method may further comprise a step for forming an Organic Light Emitting Diode (OLED), wherein

-forming a first anode electrode on a substrate,

-forming a light emitting layer on the first anode electrode,

-forming an electron transport layer stack structure on the light emitting layer, preferably a first electron transport layer and an optional second electron transport layer on the light emitting layer,

-and finally forming a cathode electrode,

-forming an optional hole injection layer, a hole transport layer and a hole blocking layer in that order between the first anode electrode and the light-emitting layer,

-forming an optional electron injection layer between the electron transport layer and the cathode electrode.

According to various embodiments of the present invention, the method may further include forming an electron injection layer on the first electron transport layer. However, according to various embodiments of the OLED of the present invention, the OLED may not comprise an electron injection layer.

According to various embodiments, the OLED may have a layer structure in which the layers have the following order:

an anode, a hole injection layer, a first hole transport layer, a second hole transport layer, a light emitting layer, an optional second electron transport layer, a first electron transport layer comprising the compound of formula 1 according to the present invention, an optional electron injection layer and a cathode.

According to another aspect of the present invention, there is provided an electronic device comprising at least one organic light emitting device according to any of the embodiments described throughout this application, preferably an organic light emitting diode in one of the embodiments described throughout this application. More preferably, the electronic device is a display device.

In one embodiment, the organic electronic device comprising an organic semiconductor layer according to the present invention may further comprise a layer comprising a radialene compound and/or a quinodimethane compound.

In one embodiment, the radialene compound and/or the quinodimethane compound may be substituted with one or more halogen atoms and/or one or more electron withdrawing groups. The electron-withdrawing group may be selected from a nitrile group, a haloalkyl group, or from a perhaloalkyl group, or from a perfluoroalkyl group. Other examples of electron withdrawing groups may be acyl, sulfonyl or phosphoryl groups.

Alternatively, the acyl group, sulfonyl group, and/or phosphoryl group may comprise a halogenated and/or perhalogenated hydrocarbon group. In one embodiment, the perhalogenated hydrocarbon group may be a perfluorinated hydrocarbon group. Examples of perfluoroalkyl groups may be perfluoromethyl, perfluoroethyl, perfluoropropyl, perfluoroisopropyl, perfluorobutyl, perfluorophenyl, perfluorotolyl; examples of the sulfonyl group containing a halogenated hydrocarbon group may be trifluoromethylsulfonyl, pentafluoroethylsulfonyl, pentafluorophenylsulfonyl, heptafluoropropylsulfonyl, nonafluorobutylsulfonyl and the like.

In one embodiment, the limonene and/or quinodimethane compounds are included in the hole injection layer, hole transport layer, and/or hole generating layer.

In one embodiment, the radialene compound may have formula (XX) and/or the quinodimethane compound may have formula (XXIa) or (XXIb):

wherein R is¹、R²、R³、R⁴、R⁵、R⁶、R⁷、R⁸、R¹¹、R¹²、R¹⁵、R¹⁶、R²⁰、R²¹Is independently selected from the above electron withdrawing groups, and R⁹、R¹⁰、R¹³、R¹⁴、R¹⁷、R¹⁸、R¹⁹、R²²、R²³And R²⁴Independently selected from: H. halogen and the electron withdrawing groups described above.

Hereinafter, embodiments will be described in more detail with reference to examples. However, the present invention is not limited to the following examples. Reference will now be made in detail to exemplary aspects.

Details and definitions of the invention

The term "borate" refers to an inorganic or organic boron anion. In one embodiment, the borate may be composed of a central boron atom and four organic groups, i.e., may have the general formula BR₄. In one embodiment, at least one group R may be a heterocyclic group. The borate ligand (═ borate anion) is negatively charged. The negative charge is balanced by divalent vs. cationic charge.

In the present specification, when a definition is not otherwise provided, "alkyl group" may refer to an aliphatic hydrocarbon group. An alkyl group may refer to a "saturated" group without any double or triple bondsAnd an alkyl group ". The term "alkyl" as used herein shall encompass linear as well as branched and cyclic alkyl groups. E.g. C₃The alkyl group may be chosen from n-propyl and isopropyl. Likewise, C₄Alkyl includes n-butyl, sec-butyl and tert-butyl. Likewise, C₆Alkyl includes n-hexyl and cyclohexyl.

C_nThe subscript n in (a) relates to the total number of carbon atoms in the corresponding alkyl, aryl, heteroaryl or aryl group.

The term "aryl" or "arylidene" as used herein shall encompass: phenyl (C)₆-aryl); fused aromatic compounds such as naphthalene, anthracene, phenanthrene, tetracene, and the like. Also contemplated are biphenyls and oligobenzenes or polyphenyls such as terphenyls and the like. Any other aromatic hydrocarbon substituent such as fluorenyl and the like is also contemplated. Aryl, heteroaryl, respectively, refer to groups linked to two additional moieties. In the present specification, the "arylidene group" may refer to a group including at least one hydrocarbon aromatic moiety, and all elements of the hydrocarbon aromatic moiety may have p orbitals forming a conjugate, such as a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a pyrenyl group, a fluorenyl group, and the like. The arylidene groups can include monocyclic, polycyclic, or fused-ring polycyclic (i.e., rings that share adjacent pairs of carbon atoms) functional groups.

As used herein, the term "heteroaryl" or "heteroarylene" refers to an aryl group in which at least one carbon atom is substituted with a heteroatom, preferably selected from: n, O, S, B or Si.

C_nThe subscript number n in heteroaryl refers only to the number of carbon atoms excluding the number of heteroatoms. In this context, it is clear that C₃Heteroarylidene radicals are aromatic compounds containing three carbon atoms, e.g. pyrazoles, imidazoles,Oxazoles, thiazoles, and the like.

The term "heteroaryl" may refer to an aromatic heterocyclic ring having at least one heteroatom, and all elements of the hydrocarbon heteroaromatic moiety may have a p-orbital that forms a conjugate. The heteroatoms may be selected from: n, O, S, B, Si, P, Se, preferably selected from: n, O and S. The heteroaryl subunit ring may comprise at least 1to 3 heteroatoms. Preferably, the heteroaryl subunit ring may comprise at least 1to 3 heteroatoms independently selected from N, S and/or O.

The term "heteroarylene" as used herein shall include pyridine, quinoline, quinazoline, pyridine, triazine, benzimidazole, benzothiazole, benzo [4,5 ] benzo]Thieno [3,2-d]Pyrimidines, carbazoles, xanthenes, thiophenesOxazines, benzacridine, dibenzoacridine, and the like.

In the present specification, a single bond means a direct bond.

The expression "between … …" with respect to a layer being between two other layers does not exclude the presence of further layers which may be arranged between this layer and one of the two other layers, according to the invention. The expression "in direct contact" in relation to two layers being in direct contact with each other means that no further layer is arranged between the two layers according to the invention. A layer deposited on top of another layer is considered to be in direct contact with that layer.

For the organic semiconductor layer of the present invention and the compound of the present invention, the compounds mentioned in the experimental section are most preferable.

The organic electronic device of the present invention may be an organic electroluminescent device (OLED), an organic photovoltaic device (OPV), a lighting device or an Organic Field Effect Transistor (OFET). The illumination device may be any device for illumination, radiation, signals or projection. They are classified accordingly as illumination, radiation, signaling and projection devices. The lighting device is generally composed of the following elements: a source of optical radiation; means for transmitting the radiant flux into the space in a desired direction; and an enclosure that connects the components into a single device and protects the radiation source and light delivery system from damage and environmental influences.

According to another aspect, the organic electroluminescent device according to the present invention may comprise more than one light-emitting layer, preferably two or three light-emitting layers. OLEDs comprising more than one light emitting layer are also described as tandem OLEDs or stacked OLEDs.

Organic electroluminescent devices (OLEDs) may be bottom-or top-emitting devices.

Another aspect relates to an apparatus comprising at least one organic electroluminescent device (OLED). The device comprising organic light emitting diodes is for example a display or a lighting panel.

In the present invention, for the terms defined next, these definitions shall be applied, unless a different definition is given in the claims or elsewhere in this specification.

In the context of the present specification, the term "different" in relation to the matrix material means that the matrix material differs in its structural formula.

The energy levels of the highest occupied molecular orbital (also called HOMO) and the lowest unoccupied molecular orbital (also called LUMO) were measured indirectly in electron volts (eV) by cyclic voltammetry relative to ferrocene, or can be calculated using the simulated B3LYP and 6-31G basis sets.

The terms "OLED" and "organic light emitting diode" are used simultaneously and have the same meaning. The term "organic electroluminescent device" as used herein may include organic light emitting diodes as well as Organic Light Emitting Transistors (OLETs).

As used herein, "weight percent," "wt%", "percent weight," "wt%", "wt% weight," and variations thereof, refers to the weight of a composition, component, substance, or agent, expressed as the component, substance, or agent of the respective electron transport layer, divided by the total weight of its respective electron transport layer, and multiplied by 100. It is understood that the amount of all components, species and agents of the respective electron transport and electron injection layers, in total weight percent, is selected such that it does not exceed 100 weight percent.

As used herein, "volume percent," "volume%", "percent volume," "volume%" and variations thereof refer to the representation of a composition, component, substance, or agent as the volume of the component, substance, or agent of the respective electron transport layer divided by the total volume of its respective electron transport layer and multiplied by 100. It is to be understood that the amount of all components, substances and agents of the cathode layer as a percentage of the total volume is selected such that it does not exceed 100 volume%.

All numerical values are herein assumed to be modified by the term "about," whether or not explicitly indicated. As used herein, the term "about" refers to a change in amount that can occur. The claims include equivalent amounts of the recited amounts, whether or not modified by the term "about".

It should be noted that, as used in this specification and the claims, the singular forms "a," "an," "the," and "the" include plural referents unless the content clearly dictates otherwise.

The terms "free", "free" and "not comprising" do not exclude impurities. The impurities have no technical effect on the object achieved by the present invention.

In the context of the present specification, the term "substantially non-luminescent" or "non-luminescent" means that the contribution of a compound or layer to the visible light emission spectrum from the device is less than 10%, preferably less than 5%, relative to the visible light emission spectrum. The visible light emission spectrum is a light emission spectrum having a wavelength of about 380nm or more to about 780nm or less.

Preferably, the organic semiconductor layer comprising the compound of formula I is substantially non-emissive or non-emissive.

The operating voltage, also known as U, is in volts (V) at 10 milliamperes per square centimeter (mA/cm)²) The following measurements were made.

Candela/ampere efficiency, also known as cd/a efficiency, in candela/ampere units at 10 milliamperes per square centimeter (mA/cm)²) The following measurements were made.

External quantum efficiency, also known as EQE, is measured in percent (%).

The color space is described by the coordinates CIE-x and CIE-y (International Commission on illumination 1931). CIE-y is particularly important for blue emission. The smaller CIE-y indicates a darker blue color.

The highest occupied molecular orbital (also known as HOMO) and the lowest unoccupied molecular orbital (also known as LUMO) are measured in electron volts (eV).

The terms "OLED", "organic light emitting diode", "organic light emitting device", "organic optoelectronic device" and "organic light emitting diode" are used simultaneously and have the same meaning.

The term "transition metal" refers to and includes any element in the d-block of the periodic table that includes elements from groups 3 to 12 in the periodic table.

The term "group III to VI metal" refers to and encompasses any metal from groups III to VI of the periodic table of elements.

The terms "life-span" and "life" are used simultaneously and have the same meaning.

All numerical values are herein assumed to be modified by the term "about," whether or not explicitly indicated. As used herein, the term "about" refers to a change in amount that can occur.

The claims include equivalent amounts of the recited amounts, whether or not modified by the term "about".

It should be noted that, as used in this specification and the claims, the singular forms "a," "an," "the," and "the" include plural referents unless the content clearly dictates otherwise.

The anode and cathode may be described as anode/cathode or anode/cathode layers.

Dipole moment of molecules containing N atomsGiven by:

wherein q is_iAndis an atom inPartial charge and position in the daughter.

The dipole moment is determined by a semi-empirical molecular orbital method.

Partial charges and atomic positions in the gas phase were obtained using the hybridization functional B3LYP and 6-31G-base sets as implemented in package turbo role V6.5. If more than one constellation is feasible, the constellation with the lowest total energy is selected to determine the dipole moment.

The reduction potential can be determined by cyclic voltammetry using a potentiostat Metrohm PGSTAT30 and software MetrohmAutolab GPES at room temperature. The redox potential was measured in an argon-degassed anhydrous 0.1M THF solution of the compound of the formula I under an argon atmosphere with a 0.1M tetrabutylammonium hexafluorophosphate supporting electrolyte between platinum working electrodes and with an Ag/AgCl pseudo-standard electrode (Metrohm silver rod electrode) consisting of a silver wire covered with silver chloride and immersed directly into the measurement solution, at a scan rate of 100 mV/s. The first run is done over the widest range of potentials set on the working electrode, and then the range is adjusted appropriately in subsequent runs. The last three runs were done with addition of ferrocene (0.1M concentration) as standard. By subtracting for standard Fc⁺The average of the potentials of the cathodic and anodic peaks corresponding to the compound was determined from the average of the cathodic and anodic potentials observed for the/Fc redox couple.

Room temperature, also referred to as ambient temperature, was 23 ℃.

Drawings

These and/or other aspects and advantages of the present invention will become apparent and more readily appreciated from the following description of exemplary embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic cross-sectional view of an Organic Light Emitting Diode (OLED) according to an exemplary embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view of an OLED according to an exemplary embodiment of the present invention;

fig. 3 is a schematic cross-sectional view of a tandem OLED including a charge generation layer according to an exemplary embodiment of the present invention.

Detailed Description

Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The exemplary embodiments are described below in order to explain aspects of the present invention by referring to the figures.

When a first element is referred to herein as being formed or disposed "on" a second element, the first element can be disposed directly on the second element, or one or more other elements can be disposed therebetween. When a first element is referred to as being "directly" formed or disposed on or to a second element, there are no other elements disposed between them.

Fig. 1 is a schematic cross-sectional view of an Organic Light Emitting Diode (OLED)100 according to an exemplary embodiment of the present invention. The OLED 100 includes a substrate 110, an anode 120, a Hole Injection Layer (HIL)130, a Hole Transport Layer (HTL)140, an emission layer (EML)150, and an Electron Transport Layer (ETL) 160. An Electron Transport Layer (ETL)160 is formed on the EML 150. An Electron Injection Layer (EIL)180 is disposed onto the Electron Transport Layer (ETL) 160. The cathode 190 is disposed directly onto the Electron Injection Layer (EIL) 180.

Instead of a single electron transport layer 160, an electron transport layered layer structure (ETL) may optionally be used.

Fig. 2 is a schematic cross-sectional view of an OLED 100 according to another exemplary embodiment of the present invention. Fig. 2 differs from fig. 1 in that the OLED 100 of fig. 2 includes an Electron Blocking Layer (EBL)145 and a Hole Blocking Layer (HBL) 155.

Referring to fig. 2, the OLED 100 includes a substrate 110, an anode 120, a Hole Injection Layer (HIL)130, a Hole Transport Layer (HTL)140, an Electron Blocking Layer (EBL)145, an emission layer (EML)150, a Hole Blocking Layer (HBL)155, an Electron Transport Layer (ETL)160, an Electron Injection Layer (EIL)180, and a cathode 190.

Fig. 3 is a schematic cross-sectional view of a tandem OLED 200 according to another exemplary embodiment of the present invention. Fig. 3 is different from fig. 2 in that the OLED 100 of fig. 3 further includes a Charge Generation Layer (CGL) and a second light emitting layer (151).

Referring to fig. 3, the OLED 200 includes a substrate 110, an anode 120, a first Hole Injection Layer (HIL)130, a first Hole Transport Layer (HTL)140, a first Electron Blocking Layer (EBL)145, a first light emitting layer (EML)150, a first Hole Blocking Layer (HBL)155, a first Electron Transport Layer (ETL)160, an n-type charge generation layer (n-type CGL)185, a hole generation layer (p-type charge generation layer), a p-type GCL)135, a second Hole Transport Layer (HTL)141, a second Electron Blocking Layer (EBL)146, a second light emitting layer (EML)151, a second hole blocking layer (EBL)156, a second Electron Transport Layer (ETL)161, a second Electron Injection Layer (EIL)181, and a cathode 190.

Although not shown in fig. 1,2 and 3, a sealing layer may be further formed on the cathode electrode 190 to seal the OLEDs 100 and 200. In addition, various other modifications may be applied thereto.

Experimental part

The performance of the inventive materials comprising divalent metal n-type dopant/electron injection materials E1, E2, and B1 were compared to the closest prior art materials comprising monovalent metal salt C1 as the n-type dopant using the model blue OLED device below.

Compound E1, CAS 12149-62-1,compound E2, CAS 12149-65-4,

compound B1, CAS 14784-09-9.

The ETL material closest to the prior art contains lithium tetrakis (1H-pyrazol-1-yl) borate as n-type dopant,

C1，CAS 14728-62-2。

the formula of the support material mentioned in the table below is as follows:

f1 is

Biphenyl-4-yl (9, 9-diphenyl-9H-fluoren-2-yl) - [4- (9-phenyl-9H-carbazol-3-yl) phenyl ] -amine, CAS1242056-42-3,

f2 is

N, N-bis (4- (dibenzo [ b, d ] furan-4-yl) phenyl) - [1,1':4',1 "-terphenyl ] -4-amine, CAS 1198399-61-9;

f3 is

9- ([1,1' -biphenyl ] -3-yl) -9' - ([1,1' -biphenyl ] -4-yl) -9H,9' H-3,3' -bicarbazole, CAS 1643479-47-3;

f4 is

2, 4-diphenyl-6- (3'- (bistriphenyl-2-yl) - [1,1' -biphenyl ] -3-yl) -1,3, 5-triazine, 1638271-85-8;

PD-2 is

4,4',4 "- ((1E,1' E, 1" E) -cyclopropane-1, 2, 3-triylidene tris (cyanomethylidene)) tris (2,3,5, 6-tetrafluorobenzonitrile), CAS 1224447-88-4.

H06 is the emitter host and DB-200 is the blue fluorescent emitter dopant, all of which are commercially available from Korean SFC.

Exemplary ETL matrix compounds M1 and M2 have the following formula:

m1 is

(i)

Diphenyl (3'- (10-phenylanthran-9-yl) - [1,1' -biphenyl ] -4-yl) phosphine oxide, CAS2138371-45-4, published in EP 3232490 and WO2017/178392,

and used as a comparative ETL matrix in the present invention.

M2 is

Dimethyl (3'- (10-phenylanthran-9-yl) - [1,1' -biphenyl ] -3-yl) phosphine oxide, CAS2101720-06-1, published in WO2017/102822,

and are used in the present invention as matrix components for the semiconductor material of the present invention.

The structure of the model device is shown in table 1 a.

TABLE 1a

Layer(s)	Composition of	c [ weight% ]]	d[nm]
				Anode	Ag	100	100
HIL	F1:PD-2	92:8	10
				HTL	F1	100	117.5
EBL	F2	100	5
				EML	H06:BD200	97:3	20
HBL	F3:F4	70:30	5
				ETL	ETL matrix n-type dopant	70:30	31
EIL	Yb	100	2
				Cathode electrode	Ag	100	11
Cover layer	F1	100	75

The performance of the model device in the following respects is given in table 1 b: a working voltage U; CIE coordinate y in color space; brightness; a current density j; current efficiency C_eff(ii) a Lifetime (defined as the time at which the brightness of a device operating at current density j drops to 97% of its initial value); and a voltage rise d (U) after 100 hours of operation at 85 ℃.

TABLE 1b

The selection of a divalent metal salt in combination with a dialkylphosphine oxide matrix may improve the operating voltage stability at high temperatures compared to n-type doped ETL materials comprising prior art compound C1 and/or triarylphosphine oxide matrix.

The features disclosed in the foregoing description, in the claims and/or in the accompanying drawings may, both separately and in any combination thereof, be material for realizing the invention in diverse forms thereof.