Method for preparing organic semiconductor layer, composition used in the method, and organic electronic device

Abstract

The present invention relates to a method for preparing an organic semiconductor layer, which comprises the following steps: a) providing a first composition in a first vacuum thermal evaporation source, wherein the first composition comprises aa) a first organic compound, wherein the first organic compound comprises at least one unsubstituted or substituted C 10 ‑C 30 A fused aryl group and / or at least one unsubstituted or substituted C3-C 30 A heteroaryl group wherein the one or more substituents, if present, are selected from the group consisting of: (i) deuterium, (ii) halogen, (iii) C1 to C 22 Silyl group, (iv) C1 to C 30 Alkyl group, (v) C1 to C 10 Alkylsilyl group, (vi) C6 to C 22 Arylsilyl group, (vii) C3 to C 30 Cyclic alkyl group, (viii) C2 to C 30 Heterocyclic alkyl group, (ix) C6 to C 30 Aryl group, (x) C2 to C 30 Heteroaryl group, (xi) C1 to C 30 a perfluoroalkyl group, or (xii) C1 to C 10 trifluoroalkyl group, wherein the first organic compound has i) a dipole moment in the range of ≥0 Debye and ≤2 Debye; ii) a molecular weight in the range of ≥400 and ≤1,800; and bb) a metal borate compound; b) converting the first composition from a solid phase to a gas phase in a vacuum chamber; and c) depositing the first composition on a substrate to form the organic semiconductor layer; and also relates to a composition used therein and an organic electronic device prepared by the method.

Description

Technical Field

[0001] The present invention relates to a method for preparing an organic semiconductor layer and a composition used in the method. The present invention also relates to an organic electronic device obtainable by a series of steps including the method. Background Art

[0002] Organic light-emitting diodes (OLEDs) as self-luminous devices have wide viewing angles, excellent contrast, fast response, high brightness, excellent driving voltage characteristics and color reproducibility. A typical OLED includes an anode, a hole transport layer (HTL), an emitting layer (EML), an electron transport layer (ETL) and a cathode stacked sequentially on a substrate. In this regard, HTL, EML and ETL are thin films formed of organic and / or organometallic compounds.

[0003] When voltage is applied to the anode and cathode, holes injected from the anode electrode move to the EML via the HTL, and electrons injected from the cathode electrode move to the EML via the ETL. 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.

[0004] Organic electronic devices typically include a substrate and multiple organic semiconductor layers. These can be prepared by evaporating different compounds from a vacuum thermal evaporation (VTE) source and depositing them on a substrate to form an organic semiconductor layer. During large-scale production of semiconductor layers, the VTE source is usually moved back and forth under the substrate to be coated, see, for example, KR20150080213. If two compounds are evaporated from separate sources, the lateral uniformity may be poor because one compound is deposited first and then the other compound is deposited. This may result in reduced performance and / or stability. Specifically, the performance of the layer composed of metal organic complexes may deteriorate.

[0005] A method for preparing an organic semiconductor layer using a composition comprising at least two compounds and subliming it from a single vacuum thermal evaporation source is known from WO 2018 / 041864 A1.

[0006] However, there is still a need for improved methods of preparing organic semiconductor layers for use in organic electronic devices such as OLEDs.

[0007] Furthermore, there is still a need to provide compositions for producing organic semiconductor layers which have improved thermal properties compared to the prior art, such as improved thermal conductivity in VTE sources.

[0008] Therefore, it is an object of the present invention to provide a novel method for preparing an organic semiconductor layer which overcomes the disadvantages of the prior art, in particular a method suitable for preparing a uniform organic semiconductor layer comprising at least two compounds having beneficial thermal properties. That is, it is an object of the present invention to provide a method for preparing an organic semiconductor layer comprising at least two compounds, wherein the different compounds are uniformly mixed with each other in the resulting organic semiconductor layer.

[0009] Another object of the present invention is to provide a composition having improved thermal properties, in particular for evaporation from a VTE source. Summary of the invention

[0010] The above object is achieved by a method for preparing an organic semiconductor layer, the method comprising the following steps:

[0011] a) providing a first composition in a first vacuum thermal evaporation source, wherein the first composition comprises:

[0012] aa) a first organic compound, the first organic compound comprising at least one unsubstituted or substituted C 10 To C 30 A fused aryl group and / or at least one unsubstituted or substituted C3 to C 30 A heteroaryl group wherein one or more substituents, if present, are independently selected from the group consisting of: (i) deuterium, (ii) halogen, (iii) C1 to C 22 Silyl group, (iv) C1 to C 30 Alkyl group, (v) C1 to C 10 Alkylsilyl group, (vi) C6 to C 22 Arylsilyl group, (vii) C3 to C 30 Cyclic alkyl group, (viii) C2 to C 30 Heterocyclic alkyl group, (ix) C6 to C 30 Aryl group, (x) C2 to C 30 Heteroaryl group, (xi) C1 to C 30 a perfluoroalkyl group, or (xii) C1 to C 10 trifluoroalkyl group,

[0013] wherein the first organic compound has:

[0014] i) a dipole moment in the range ≥ 0 Debye and ≤ 2 Debye; and

[0015] ii) a molecular weight in the range of ≥400 and ≤1,800; and

[0016] bb) metal borate compounds;

[0017] b) transforming the first composition from a solid phase to a gas phase in a vacuum chamber; and

[0018] c) depositing the first composition to form an organic semiconductor layer.

[0019] Surprisingly, the present inventors have found that the above method offers the possibility of providing an organic semiconductor layer in which the first organic compound and the metal borate compound are uniformly mixed with each other, ie provides a method for avoiding the formation of a layer consisting of the metal borate compound.

[0020] Furthermore, it was found that the conductivity of the organic semiconductor layer formed by the method according to the invention is significantly improved compared to a layer composed of a metal borate compound. This allows lower operating voltages and longer battery life, in particular in mobile electronic devices.

[0021] In addition, it is found that if the dipole moment of the first organic compound is in the range of ≥0 Debye and ≤2 Debye, the first composition can be transformed from the solid phase into the gas phase without significant decomposition. In particular, it is found that even if the first composition is partially or completely melted before or during the first composition is transformed into the gas phase, no significant decomposition occurs. Without being bound by theory, it is believed that the composition at least partially melted in the VTE source can have improved thermal conductivity compared to the composition that is not melted in the VTE source during the manufacture of the device. Thus, the heat distribution in the VTE source can be improved.

[0022] A vacuum thermal evaporation source may also be described as a VTE source, a thermal evaporation source, an evaporator deposition source, a nozzle source, a showerhead source, a VTE unit, a thermal evaporation unit, an evaporation unit or a sublimation unit. The vacuum thermal evaporation source is arranged in a vacuum chamber.

[0023] The VTE source includes a container for the composition, a heating element for heating the container, and at least one thermocouple for measuring the temperature of the container. The container can be a crucible. The container is composed of an inert material such as Al2O3 or Ti. In addition, the VTE source can include a lid having an opening such as a nozzle for releasing the gas phase composition into the vacuum chamber. The lid can be heated to reduce the risk of clogging of the opening or nozzle.

[0024] The VTE source can be moved back and forth or rotated under the substrate. Alternatively, the VTE source can be stationary and the substrate can be moved over the source.

[0025] In the context of the present invention, the term "evaporation" means the conversion of a compound or composition from the solid phase into the gaseous phase independently of any phase transition at elevated temperature.

[0026] In the context of the present invention, the term "vacuum chamber" refers to the location where the transition of the first composition from the solid phase to the gas phase occurs. Subsequent deposition of the first composition on the solid support also occurs in the vacuum chamber. The vacuum chamber is made of metal or other mechanically stable materials and can be evacuated to create a vacuum in the vacuum chamber. The vacuum chamber can also be described as a deposition chamber, a processing chamber, a sublimation chamber or an evaporation chamber.

[0027] The pressure in the vacuum chamber in step b) can be 10 -2 mbar to 10 -9 mbar range, preferably 10 -3 mbar to 10 -8 Under such pressure, the transfer of the first composition from the solid phase to the gas phase can be well achieved.

[0028] Dipole moment of a molecule containing N atoms Given by:

[0029]

[0030]

[0031] where q i and is the partial charge and position of atom i in the molecule.

[0032] The dipole moments were determined by the semiempirical molecular orbital method.

[0033] The geometry of the molecular structure was optimized in the gas phase using the hybrid functional B3LYP and 6-31G* basis set as implemented in the program package TURBOMOLE V6.5 (TURBOMOLE GmbH, Litzenhardtstrasse 19, 76135 Karlsruhe, Germany). If more than one conformation was feasible, the conformation with the lowest total energy was selected to determine the bond lengths of the molecule.

[0034] The molecular weight is calculated based on the chemical formula of a single unit (also referred to as a monomer) of the first organic compound or metal borate compound and is measured in grams per mole (g / mol). The term single unit is particularly applicable if the first organic compound or metal borate compound is in the form of a dimer or trimer. If dimers or trimers (or oligomers / polymers) are not formed, the molecular weight of the single unit is the same as the molecular weight of the first organic compound or metal borate compound. If the molecular weight is selected within this range, the compound can be converted into the gas phase at a temperature and rate suitable for large-scale production.

[0035] According to another embodiment, the first organic compound has:

[0036] i) a dipole moment in the range of ≥ 0 Debye and ≤ 1.8 Debye, or ≥ 0 Debye and ≤ 1.6 Debye, or ≥ 0 Debye and ≤ 1.4 Debye, or ≥ 0.1 Debye and ≤ 1.2 Debye; and / or

[0037] ii) a molecular weight in the range of ≥410 and ≤1,600, or ≥410 and ≤1,400, or ≥420 and ≤1,400, or ≥420 and ≤1,200, or ≥420 and ≤1,000, or ≥420 and ≤800, or ≥420 and ≤700.

[0038] According to the invention, it can be provided that the first composition comprises one or two or more first organic compounds. Likewise, it can be provided that the first composition comprises one metal borate compound or two or more metal borate compounds.

[0039] With regard to the process according to the invention, step b) thereof, it can be provided that the conversion of the first composition from the solid phase into the gas phase comprises a further step of converting the first composition from the solid phase into an at least partially molten state before the conversion into the gas phase. In other words, it can be provided that the first composition does not (at least partially) sublime (convert directly from the solid phase into the gas phase), but rather (at least partially) converts from the liquid phase into the gas phase.

[0040] According to another aspect of the present invention, the first composition, ie, a mixture comprising a first organic compound and a metal borate compound (or two or more corresponding compounds), can be transformed into a gas phase from a single vacuum thermal evaporation source as a first vacuum thermal evaporation source.

[0041] The term "single vacuum thermal evaporation source" as used herein should not be interpreted in the way that only one single vacuum thermal evaporation source can be arranged in the vacuum chamber. On the contrary, it can be provided that more than one single vacuum thermal evaporation source can be used in parallel, at least one of which contains the first composition. In this respect, the term "single" is to be understood as the concept according to the invention that the first component is evaporated from only one (single) evaporation source.

[0042] According to the method of the present invention, it is provided that in step c) the first composition is deposited on the surface of the aforementioned layer to form an organic semiconductor layer. In this regard, the aforementioned layer can in principle be any layer usually contained in an organic electronic device and mentioned in the "other layers" section herein.

[0043] With regard to the method of the invention, it can be provided that the first composition consists of a first organic compound (or two or more corresponding compounds) and a metal borate compound (or two or more corresponding metal borate compounds), i.e., in addition to the one or more first organic compounds and the one or more metal borate compounds, the composition also contains further compounds in an amount which cannot be avoided only by ordinary technical means.

[0044] The first composition can be prepared by mixing the first organic compound and the metal borate compound in solid phase, by co-evaporation and subsequent condensation, by melting and subsequent cooling, or by dissolution in a solvent and subsequent removal of the solvent.

[0045] It may be provided that the first organic compound comprises at least one group selected from the group consisting of: C 10 To C 24 A fused aryl group, or C 10 To C 18 A fused aryl group, or naphthyl, anthracenyl, fluoranthenyl, phenanthrenyl, pyrenyl, fluorenyl; and / or C3 to C 24 Heteroaryl groups, or C3 to C 21 A heteroaryl group, or a triazine group, a pyrazinyl group, an acridinyl group, a benzoacridinyl group, a dibenzoacridinyl group, a xanthenyl group, a pyrimidinyl group, a quinolyl group, a benzoquinolyl group, a quinoxalinyl group, a benzoquinoxaline group, a benzofuranyl group, a benzothienyl group, a dibenzofuranyl group, a dibenzothienyl group.

[0046] The heteroaryl group may contain one to three heteroatoms independently selected from N, O or S, or one to three N atoms or one O or S atom. Likewise, it may be provided that the first organic compound contains at least one group selected from: C 10 To C 24 A fused aryl group, or C 10 To C 18 A fused aryl group, or anthracenyl, fluoranthene, phenanthryl; and / or C3 to C 24 A heteroaryl group, or a C3 to C 21 A heteroaryl group, or a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, or a dibenzothiophenyl group.

[0047] It may be provided that the first organic compound comprises at least one group selected from the group consisting of: C 10 To C 24 A fused aryl group, or C 10 To C 18 A fused aryl group, or a fluorenyl group, a naphthyl group, an anthracenyl group, a fluoranthenyl group, a phenanthrenyl group, a pyrenyl group and no heteroatoms.

[0048] The first organic compound may also include a group selected from the following: a substituted or unsubstituted spiro[fluorene-9,9'-xanthene]-yl group, a substituted or unsubstituted 9,9'-dimethylfluorenyl group, a substituted or unsubstituted 9,9'-diphenylfluorenyl group, a 9,9'-spiro[difluorenyl]-yl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, a substituted or unsubstituted fluoranthene group, a substituted or unsubstituted group consisting of 3 to 6 connected benzene rings, or a substituted or unsubstituted tetraphenylvinyl group.

[0049] The first organic compound may be represented by Formula 1a

[0050]

[0051] in

[0052] A 1 , A 2 , A 3 and A 4 are independently selected from a single bond, a substituted or unsubstituted C6 to C 18 Aromatic substituent or unsubstituted or substituted C1 to C 18 heteroaromatic subunit;

[0053] A 5 Selected from unsubstituted or substituted C 10 -C 30 A fused aryl group or a group selected from unsubstituted or substituted C3-C 30 heteroaryl;

[0054] R 1 To R 5 independently selected from substituted or unsubstituted phenyl;

[0055] a) to e) are independently selected to be 0 or 1, provided that 2≤a+b+c+d+e≤5;

[0056] Wherein, in Formula 1a, one or more substituents, if present, are independently selected from:

[0057] (i) deuterium,

[0058] (ii) halogen,

[0059] (iii) C1 to C 22 Silyl group,

[0060] (iv) C1 to C 30 Alkyl groups,

[0061] (v) C1 to C 10 Alkylsilyl group,

[0062] (vi) C6 to C 22 Arylsilyl group,

[0063] (vii) C3 to C 30 Cyclic alkyl groups,

[0064] (viii) C2 to C 30 Heterocyclic alkyl groups,

[0065] (ix) C6 to C 30 Aryl groups,

[0066] (x) C2 to C 30 Heteroaryl groups,

[0067] (xi) C1 to C 30 a perfluoroalkyl group, or

[0068] (xii) C1 to C 10 trifluoroalkyl group;

[0069] and / or

[0070] The first organic compound may be represented by Formula 1b

[0071]

[0072] in

[0073] A 1 , A 2 , A 3 and A 4 are independently selected from a single bond, a substituted or unsubstituted C6 to C 18 Aromatic substituent or unsubstituted or substituted C1 to C 18 heteroaromatic subunit;

[0074] A 5 Selected from unsubstituted or substituted C 10 To C 30 A fused aryl group or a group selected from unsubstituted or substituted C3 to C 30 heteroaryl;

[0075] R 1 To R 3 independently selected from substituted or unsubstituted phenyl;

[0076] Wherein, in Formula 1b, one or more substituents, if present, are independently selected from the following:

[0077] (i) deuterium,

[0078] (ii) halogen,

[0079] (iii) C1 to C 22 Silyl group,

[0080] (iv) C1 to C 30 Alkyl groups,

[0081] (v) C1 to C 10 Alkylsilyl group,

[0082] (vi) C6 to C 22 Arylsilyl group,

[0083] (vii) C3 to C 30 Cyclic alkyl groups,

[0084] (viii) C2 to C 30 Heterocyclic alkyl groups,

[0085] (ix) C6 to C 30 Aryl groups,

[0086] (x) C2 to C 30 Heteroaryl groups,

[0087] (xi) C1 to C 30 Perfluoroalkyl groups,

[0088] (xii) C1 to C 10 trifluoroalkyl group;

[0089] and / or

[0090] The first organic compound may be represented by Formula 1c

[0091]

[0092] in

[0093] The compound of formula (1c) comprises a moiety -A 1 -A 2 -A 3 -A 4 -A 5 , where the asterisk symbol "*" marks part -A 1 -A 2 -A 3 -A 4 -A 5 possible bonding sites to the rest of the structure;

[0094] A 1 , A 2 , A 3 and A 4 are independently selected from a single bond, a substituted or unsubstituted C6 to C 18 Aromatic substituent or unsubstituted or substituted C1 to C 18 heteroaromatic subunit;

[0095] A5 Selected from unsubstituted or substituted C 10 To C 30 A fused aryl group or a group selected from unsubstituted or substituted C3 to C 30 heteroaryl;

[0096] Wherein, in Formula 1c, one or more substituents, if present, are independently selected from the following:

[0097] (i) deuterium,

[0098] (ii) halogen,

[0099] (iii) C1 to C 22 Silyl group,

[0100] (iv) C1 to C 30 Alkyl groups,

[0101] (v) C1 to C 10 Alkylsilyl group,

[0102] (vi) C6 to C 22 Arylsilyl group,

[0103] (vii) C3 to C 30 Cyclic alkyl groups,

[0104] (viii) C2 to C 30 Heterocyclic alkyl groups,

[0105] (ix) C6 to C 30 Aryl groups,

[0106] (x) C2 to C 30 Heteroaryl groups,

[0107] (xi) C1 to C 30 Perfluoroalkyl groups,

[0108] (xii) C1 to C 10 trifluoroalkyl group;

[0109] and / or

[0110] The first organic compound may be represented by Formula 1d

[0111]

[0112] in

[0113] The compound of formula (1d) comprises a moiety -A 1 -A 2 -A 3 -A 4 -A 5, where the asterisk symbol "*" marks part -A 1 -A 2 -A 3 -A 4 -A 5 possible bonding sites to the rest of the structure;

[0114] Y 1 is selected from a single bond, O, S, CR2 or SiR2, wherein R is independently selected from C1 to C 12 Alkyl or C6 to C 18 Aryl;

[0115] A 1 , A 2 , A 3 and A 4 are independently selected from a single bond, a substituted or unsubstituted C6 to C 18 Aromatic substituent or unsubstituted or substituted C1 to C 18 heteroaromatic subunit;

[0116] A 5 Selected from unsubstituted or substituted C 10 To C 30 A fused aryl group or a group selected from unsubstituted or substituted C3 to C 30 heteroaryl;

[0117] Wherein, in Formula 1d, one or more substituents, if present, are independently selected from the following:

[0118] (i) deuterium,

[0119] (ii) halogen,

[0120] (iii) C1 to C 22 Silyl group,

[0121] (iv) C1 to C 30 Alkyl groups,

[0122] (v) C1 to C 10 Alkylsilyl group,

[0123] (vi) C6 to C 22 Arylsilyl group,

[0124] (vii) C3 to C 30 Cyclic alkyl groups,

[0125] (viii) C2 to C 30 Heterocyclic alkyl groups,

[0126] (ix) C6 to C 30 Aryl groups,

[0127] (x) C2 to C 30 Heteroaryl groups,

[0128] (xi) C1 to C 30 Perfluoroalkyl groups,

[0129] (xii) C1 to C 10 A trifluoroalkyl group.

[0130] In another embodiment, A 1 , A 2 , A 3 and A 4 are independently selected from a single bond, a substituted or unsubstituted C6 to C 12 Aromatic substituent or unsubstituted or substituted C3 to C 10 Heteroaromatic subunit; or, A 1 , A 2 , A 3 and A 4 are independently selected from a single bond, a substituted or unsubstituted benzene group.

[0131] In another embodiment, one or more substituents in formula (1a) to (1d), if present, are independently selected from C6 to C 12 Aryl and / or C8 to C 12 Heteroaryl.

[0132] According to another embodiment, in the compounds of the above formulae (1a) to (1d),

[0133] a)A 1 To A 3 Can be selected from single bonds, A 4 may be a phenyl group, and A 5 Can be selected from substituted or unsubstituted C 10 To C 30 A fused aryl group and / or at least one unsubstituted or substituted C3 to C 30 heteroaryl groups;

[0134] b)A 1 and A 2 Can be selected from single bonds, A 3 and A 4 may be a phenyl group, and A 5 Can be selected from substituted or unsubstituted C 10 To C 30 A fused aryl group and / or at least one unsubstituted or substituted C3 to C 30 a heteroaryl group; or

[0135] c)A 1 Can be selected from single bonds, A 2 To A4 may be a phenyl group, and A 5 Can be selected from substituted or unsubstituted C 10 To C 30 A fused aryl group and / or at least one unsubstituted or substituted C3 to C 30 heteroaryl groups;

[0136] wherein one or more substituents, if present, are independently selected from C6 to C 12 Aryl and / or C8 to C 12 Heteroaryl.

[0137] According to another embodiment, in the compounds of the above formulae (1a) to (1d),

[0138] a)A 1 To A 3 Can be selected from single bonds, A 4 may be a phenyl group, and A 5 Can be selected from substituted or unsubstituted C 10 To C 30 fused aryl groups;

[0139] b)A 1 and A 2 Can be selected from single bonds, A 3 and A 4 may be a phenyl group, and A 5 Can be selected from substituted or unsubstituted C 10 To C 30 a fused aryl group; or

[0140] c)A 1 Can be selected from single bonds, A 2 To A 4 may be a phenyl group, and A 5 Can be selected from substituted or unsubstituted C 10 To C 30 fused aryl groups;

[0141] wherein one or more substituents, if present, are independently selected from C6 to C 12 Aryl and / or C8 to C 12 Heteroaryl.

[0142] According to another embodiment, in the compounds of the above formulae (1a) to (1d),

[0143] a)A 1 To A 3 Can be selected from single bonds, A 4 may be a phenyl group, and A 5 may be selected from at least one unsubstituted or substituted C3 to C30 heteroaryl groups;

[0144] b)A 1 and A 2 Can be selected from single bonds, A 3 and A 4 may be a phenyl group, and A 5 may be selected from at least one unsubstituted or substituted C3 to C 30 a heteroaryl group; or

[0145] c)A 1 Can be selected from single bonds, A 2 To A 4 may be a phenyl group, and A 5 may be selected from at least one unsubstituted or substituted C3 to C 30 heteroaryl groups;

[0146] wherein one or more substituents, if present, are independently selected from C6 to C 12 Aryl and / or C8 to C 12 Heteroaryl.

[0147] In another embodiment, the first organic compound may comprise a substituted triazine, wherein the substituents are independently selected from C6 to C 12 Aryl and / or C8 to C 12 Preferably, C8 to C 12 The heteroaryl group contains a heteroatom selected from S or O.

[0148] In this way, the uniformity and / or conductivity of the organic semiconductor layer produced by the process according to the invention is also improved.

[0149] The metal borate compound may be an alkali metal borate compound, an alkaline earth metal borate compound or a rare earth metal borate compound having a molecular weight ranging from >100 to <1,200, or >150 to <1,000, or >200 to <800, or >250 to <600.

[0150] The metal borate compound may comprise a metal selected from an alkali metal, an alkaline earth metal, or a rare earth metal; alternatively, the metal may be selected from an alkali metal or an alkaline earth metal; alternatively, the metal may be selected from lithium, calcium, or magnesium.

[0151] In this way, the uniformity and / or conductivity of the organic semiconductor layer produced by the process according to the invention is also improved.

[0152] The metal borate compound may have the following formula:

[0153]

[0154] Where M is a metal ion, A6 To A 9 Each of which is independently selected from H, substituted or unsubstituted C6 to C 20 Aryl and substituted or unsubstituted C2 to C 20 The present invention also improves the conductivity of the organic semiconductor layer prepared by the method of the present invention.

[0155] In formula (2), n may be 1 or 2. In this way, the conductivity of the organic semiconductor layer produced by the method of the present invention is also improved.

[0156] M in Formula 2 may be an alkali metal, an alkaline earth metal or a rare earth metal, or an alkali metal or an alkaline earth metal, or may be selected from lithium, magnesium or calcium. In this way, the conductivity of the organic semiconductor layer prepared by the method of the present invention is also improved.

[0157] At least three selected from A in formula (2) 6 To A 9 The group may be a nitrogen-containing heteroaryl group. Thus, the conductivity of the organic semiconductor layer prepared by the method of the present invention is also improved.

[0158] The heteroaryl group of formula (2) may contain nitrogen, and the nitrogen-containing heteroaryl group is bonded to the central boron atom via a NN bond. In this way, the conductivity of the organic semiconductor layer prepared by the method of the present invention is also improved.

[0159] The heteroaryl group in formula (2) may be a pyrazolyl group. Thus, the conductivity of the organic semiconductor layer prepared by the method of the present invention is also improved.

[0160] The metal borate compound of formula (2) can be represented by the following formula (2a) or (2b):

[0161]

[0162] In this way, the conductivity of the organic semiconductor layer produced by the process of the invention is also improved.

[0163] According to another embodiment, the ratio of the first organic compound to the metal borate compound may be selected to be 90:10 wt % to 10:90 wt %, or 80:20 wt % to 20:80 wt %, or 70:30 wt % to 30:70 wt %.

[0164] In a preferred embodiment, the first organic compound and / or the metal borate compound is non-luminescent. Alternatively, the first composition is non-luminescent.

[0165] The method may further comprise the following steps:

[0166] e) providing a second organic compound in a second vacuum thermal evaporation source;

[0167] f) converting the second organic compound from a solid phase to a gas phase in a vacuum chamber; and

[0168] g) depositing the first composition together with the second organic compound to form an organic semiconductor layer.

[0169] In this way, the charge injection and transport properties of the semiconductor layer, in particular those associated with the cathode, may be improved.

[0170] The second organic compound may have a dipole moment in the range of >1.5 Debye and <10 Debye; and a molecular weight in the range of >400 and <1,800. Alternatively, the second organic compound may have a dipole moment in the range of >2 Debye and <8 Debye, or >3 Debye and <6 Debye, or >3.5 Debye and <6 Debye; and a molecular weight in the range of >400 and <1,600; or >410 and <1,400; or >410 and <1,200; or >410 and <1,000; or >410 and <800.

[0171] In this way, the uniformity and the charge injection and transport properties of the semiconductor layers, in particular those associated with the cathode, may be improved.

[0172] The second organic compound may include at least one group selected from the group consisting of: phenanthroline; benzimidazole; pyridin-4-yl; pyrimidine; quinoline; benzoquinoline; dibenzoquinoline; quinoxaline; benzoquinoxaline; dibenzoquinoxaline; xanthene; C=O; COOR, wherein R is selected from C1 to C 12 Alkyl or C6 to C 18 Aryl; P=X, wherein X is selected from O, S or Se, or is selected from O or S, or X is O.

[0173] According to another embodiment, the second organic compound may further comprise at least one unsubstituted or substituted C 10 To C 30 A fused aryl group and / or at least one unsubstituted or substituted C3 to C 30 A heteroaryl group wherein one or more substituents, if present, are independently selected from the group consisting of: (i) deuterium, (ii) halogen, (iii) C1 to C 22 Silyl group, (iv) C1 to C 30 Alkyl group, (v) C1 to C 10 Alkylsilyl group, (vi) C6 to C 22 Arylsilyl group, (vii) C3 to C 30 Cyclic alkyl group, (viii) C2 to C 30Heterocyclic alkyl group, (ix) C6 to C 30 Aryl group, (x) C2 to C 30 Heteroaryl group, (xi) C1 to C 30 perfluoroalkyl group, and (xii) C1 to C 10 A trifluoroalkyl group.

[0174] According to another embodiment, the second organic compound may include a phosphine oxide group and at least one unsubstituted or substituted C 10 To C 30 A fused aryl group and / or at least one unsubstituted or substituted C3 to C 30 A heteroaryl group wherein one or more substituents, if present, are independently selected from C1 to C 30 Alkyl groups, C6 to C 30 Aryl group, C2 to C 30 Heteroaryl groups.

[0175] In this way, the charge injection and transport properties of the semiconductor layer, in particular those associated with the cathode, may be improved.

[0176] Preferably, the organic semiconductor layer comprising the first composition and the optional second organic compound is substantially non-emissive or non-emissive.

[0177] The object is also achieved by an organic electronic device comprising an anode, a cathode and an organic semiconductor layer, wherein the organic semiconductor layer can be obtained by a method as described herein. In this respect, preferred embodiments concerning the above method are also preferred embodiments concerning the organic electronic device.

[0178] The organic electronic device may further include a photoactive layer disposed between the anode and the cathode. The photoactive layer may be a light emitting layer or a light absorbing layer.

[0179] In a preferred embodiment, the organic semiconductor layer may be arranged between the photoactive layer and the cathode.

[0180] The organic electronic device may further include an electron injection layer and / or a hole blocking layer.

[0181] The organic semiconductor layer may be arranged between the hole blocking layer and the cathode. Alternatively, the organic semiconductor layer may be arranged between the photoactive layer and the electron injection layer. Alternatively, the organic semiconductor layer may be arranged between the hole blocking layer and the electron injection layer.

[0182] The 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) comprising at least one first composition, and a cathode sequentially stacked on a substrate. In this regard, the HTL, EML, and ETL are thin films formed of organic compounds.

[0183] According to various embodiments, the OLED may have the following layer structure, wherein the layers may have the following order:

[0184] an anode, a hole injection layer, a first hole transport layer, a second hole transport layer, a light emitting layer, an optional hole blocking layer, an organic semiconductor layer prepared according to the process of the invention as defined herein, an optional electron injection layer and a cathode.

[0185] The organic electronic device according to one 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.

[0186] The object is also achieved by a method for preparing an organic electronic device, comprising the step of preparing an organic semiconductor layer according to the method as defined herein. The preferred embodiments as described herein with respect to the method for preparing an organic semiconductor layer also apply to the method for preparing an organic electronic device.

[0187] According to another aspect of the present invention, there is provided a method for manufacturing an organic electronic device, the method using:

[0188] - a first VTE source to release a first composition as described herein, and

[0189] - Optionally, a second VTE source to release a second organic compound;

[0190] According to various embodiments of the present invention, the method may further include the steps of: (i) forming a light-emitting layer on the anode electrode and (ii) forming at least one layer selected from the following: a hole injection layer, a hole transport layer and a hole blocking layer between the anode electrode and the first electron transport layer.

[0191] According to various embodiments of the present invention, the method may further include the step of forming an organic light emitting diode (OLED), wherein

[0192] - forming a first anode electrode on the substrate,

[0193] - forming a light emitting layer on the first anode electrode,

[0194] - forming an electron transport layer stack on the light-emitting layer, optionally forming a hole blocking layer on the light-emitting layer and forming an organic semiconductor layer,

[0195] - and finally forming a cathode electrode,

[0196] - Optionally, a hole injection layer, a hole transport layer and a hole blocking layer may be formed in sequence between the first anode electrode and the light-emitting layer,

[0197] - Optionally, an electron injection layer is formed between the organic semiconductor layer and the cathode electrode.

[0198] According to various embodiments of the present invention, the method may further include forming an electron injection layer on the organic semiconductor layer. However, according to various embodiments of the OLED of the present invention, the OLED may not include the electron injection layer.

[0199] The object is also achieved by a composition consisting of:

[0200] a) a first organic compound, the first organic compound comprising at least one C 10 To C 30 A fused aromatic group and / or at least one C3 to C 30 A heteroaryl group, wherein the first organic compound has:

[0201] (i) a dipole moment in the range ≥ 0 Debye and ≤ 2 Debye; and

[0202] (ii) a molecular weight in the range of ≥400 to ≤1,800; and

[0203] b) Metal borate compounds.

[0204] In this regard as well, the preferred embodiments described above with respect to the method for preparing an organic semiconductor layer using the first composition, ie, the first organic compound and the metal borate compound, also apply to the composition of the present invention.

[0205] The metal in the metal borate compound of the composition may in particular be selected from alkali metals, alkaline earth metals or rare earth metals, or the metal may be selected from alkali metals or alkaline earth metals, or the metal may be selected from lithium, calcium or magnesium.

[0206] With regard to the composition of the invention, it can in particular be provided that the metal borate has a molecular weight in the range of ≧100 to <1,200.

[0207] According to the invention, ie according to the method for producing an organic semiconductor layer, the organic electronic device according to the invention and the composition described herein, the following compounds are particularly preferred as first organic compound:

[0208]

[0209]

[0210]

[0211] Other layers

[0212] According to the present invention, in addition to the layers already mentioned above, the organic electronic device may further comprise other layers. Exemplary embodiments of the respective layers are described below:

[0213] Base

[0214] The substrate can be any substrate commonly used in the manufacture of electronic devices. 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 of the electronic device, the substrate can be a transparent material as well as an opaque material, such as a glass substrate, a plastic substrate, a metal substrate or a silicon substrate. The substrate can be rigid or flexible.

[0215] The organic semiconductor layer prepared by the method according to the present invention can be deposited on a substrate.

[0216] Alternatively, further layers may be arranged between the substrate and the organic semiconductor layer produced by the method according to the invention. These are described below.

[0217] Anode electrode

[0218] The first electrode or the second electrode included in the organic electronic device of the present invention can be an anode electrode. The anode electrode can be formed by depositing or sputtering a material for forming the anode electrode. The material for forming the anode electrode can be a high work function material to facilitate hole injection. The anode material can also be selected from a low work function material (i.e., aluminum). The anode electrode can be a transparent or reflective electrode. Transparent conductive oxides, such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), aluminum zinc oxide (AlZO) and zinc oxide (ZnO), can be used to form the anode electrode. The anode electrode can also be formed using a metal, typically silver (Ag), gold (Au) or a metal alloy.

[0219] Hole injection layer

[0220] The hole injection layer (HIL) can be formed on the anode electrode by vacuum deposition, spin coating, printing, casting, slot die coating, Langmuir-Blodgett (LB) deposition, etc. When the HIL is formed using vacuum deposition, the deposition conditions may vary according to the compound used to form the HIL and the desired structure and thermal properties of the HIL. However, in general, the vacuum deposition conditions may include a deposition temperature of 100° C. to 500° C., a temperature of 10 -8 Up to 10 -3 Torr (1 Torr equals 133.322 Pa) pressure and a deposition rate of 0.1 nm / s to 10 nm / s.

[0221] When the HIL is formed using spin coating or printing, the coating conditions may vary according to the compound used to form the HIL and the desired structure and thermal characteristics of the HIL. For example, the coating conditions may include a coating speed of about 2000 rpm to about 5000 rpm and a heat treatment temperature of about 80° C. to about 200° C. After coating, the heat treatment removes the solvent.

[0222] The HIL may be formed of any compound that is generally used to form a HIL. Examples of the compound that can be used to form the HIL include phthalocyanine compounds such as copper phthalocyanine (CuPc), 4,4',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).

[0223] The HIL may include or consist of a p-type dopant, and the p-type dopant may be selected from tetrafluoro-tetracyanoquinodimethane (F4TCNQ), 2,2'-(perfluoronaphthalene-2,6-diylidene)dimalononitrile, or 2,2',2"-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile), but is not limited thereto. The HIL may be selected from a hole transport host compound doped with a p-type dopant. A typical example of a known doped hole transport material is tetrafluoro-tetracyanoquinodimethane doped with a LUMO level of about -5.2 eV. Copper phthalocyanine (CuPc) with a HOMO level of about -5.2 eV of cyanoquinodimethane (F4TCNQ); zinc phthalocyanine (ZnPc) doped with F4TCNQ (HOMO = -5.2 eV); α-NPD (N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-benzidine) doped with F4TCNQ; α-NPD doped with 2,2'-(perfluoronaphthalene-2,6-diylidene) dimalononitrile. The p-type dopant concentration may be selected from 1 wt% to 20 wt%, more preferably from 3 wt% to 10 wt%.

[0224] The thickness of the HIL may be in the range of about 1 nm to about 100 nm, for example, about 1 nm to about 25 nm. When the thickness of the HIL is within the range, the HIL may have excellent hole injection characteristics without substantially deteriorating driving voltage.

[0225] Hole transport layer

[0226] The hole transport layer (HTL) can be formed on the HIL by vacuum deposition, spin coating, slot die coating, printing, casting, Langmuir-Blodgett (LB) deposition, etc. When the HTL is formed by vacuum deposition or spin coating, the conditions of deposition and coating may be similar to those for forming the HIL. However, the conditions of vacuum or solution deposition may vary depending on the compound used to form the HTL.

[0227] The HTL may be formed of any compound commonly used to form the HTL. Compounds that may be suitably used are disclosed, for example, in Yasuhiko Shirota and Hiroshi Kageyama, Chem. Rev. 2007, 107, 953-1010, which is incorporated herein by reference. Examples of compounds that may 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'-di(naphthalene-1-yl)-N,N'-diphenylbenzidine (α-NPD); and triphenylamine-based compounds such as 4,4',4"-tri(N-carbazolyl)triphenylamine (TCTA). Among these compounds, TCTA may transport holes and inhibit diffusion of excitons into the EML.

[0228] The thickness of the HTL may be in the range of about 5 nm to about 250 nm, preferably about 10 nm to about 200 nm, about 20 nm to about 190 nm, about 40 nm to about 180 nm, about 60 nm to about 170 nm, about 80 nm to about 160 nm, about 100 nm to about 160 nm, and about 120 nm to about 140 nm. The preferred thickness of the HTL may be 170 nm to 200 nm.

[0229] When the thickness of the HTL is within the range, the HTL may have excellent hole transport characteristics without substantially deteriorating driving voltage.

[0230] Electron blocking layer

[0231] The function of the electron blocking layer (EBL) is to prevent electrons from being transferred from the light-emitting layer to the hole transport layer, thereby limiting the electrons to the light-emitting layer. Thus, the efficiency, operating voltage and / or life are improved. Typically, the electron blocking layer comprises a triarylamine compound. Compared with the LUMO energy level of the hole transport layer, the triarylamine compound may have a LUMO energy level that is closer to the vacuum energy level. Compared with the HOMO energy level of the hole transport layer, the electron blocking layer may have a HOMO energy level that is further away from the vacuum energy level. The thickness of the electron blocking layer is 2nm to 20nm.

[0232] If the electron blocking layer has a high triplet energy level, it can also be described as a triplet controlling layer.

[0233] Emitting Layer (EML)

[0234] The EML can be formed on the HTL by vacuum deposition, spin coating, slot die coating, printing, casting, LB deposition, etc. When the EML is formed using vacuum deposition or spin coating, the conditions for deposition and coating may be similar to those for forming the HIL. However, the conditions for deposition and coating may vary depending on the compound used to form the EML.

[0235] It can be provided that the light-emitting layer does not contain the first composition.

[0236] The light-emitting layer (EML) may be formed of a combination of a host and a light-emitting dopant. Examples of the host are Alq3, 4,4'-N,N'-dicarbazole-biphenyl (CBP), poly(n-vinylcarbazole) (PVK), 9,10-di(naphthalene-2-yl)anthracene (ADN), 4,4',4"-tri(carbazole-9-yl)-triphenylamine (TCTA), 1,3,5-tri(N-phenylbenzimidazol-2-yl)benzene (TPBI), 3-tert-butyl-9,10-di-2-naphthylanthracene (TBADN), distyrylarene (DSA), bis(2-(2-hydroxyphenyl)benzothiazole)zinc (Zn(BTZ)2).

[0237] The emitter dopant may be a phosphorescent or fluorescent emitter. Phosphorescent emitters and emitters emitting via a thermally activated delayed fluorescence (TADF) mechanism may be preferred due to their higher efficiency. The emitter may be a small molecule or a polymer.

[0238] Examples of red emitter dopants are PtOEP, Ir(piq)3 and Btp2Ir(acac), but are not limited thereto. These compounds are phosphorescent emitters, however, fluorescent red emitter dopants may also be used.

[0239] Examples of phosphorescent green emitter dopants are Ir(ppy)3 (ppy=phenylpyridine), Ir(ppy)2(acac), Ir(mpyp)3.

[0240] Examples of phosphorescent blue emitter dopants are F2Irpic, (F2ppy)2Ir(tmd) and Ir(dfppz)3 and trifluorene. 4,4'-bis(4-diphenylaminophenylvinyl)biphenyl (DPAVBi), 2,5,8,11-tetra-tert-butylperylene (TBPe) are examples of fluorescent blue emitter dopants.

[0241] Based on 100 parts by weight of the host, the amount of the luminophore dopant may be in the range of about 0.01 parts by weight to about 50 parts by weight. Alternatively, the luminescent layer may be composed of a luminescent polymer. The EML may have a thickness of about 10 nm to about 100 nm, for example, about 20 nm to about 60 nm. When the thickness of the EML is within the range, the EML may have excellent luminescence without causing substantial damage to the driving voltage.

[0242] Hole Blocking Layer (HBL)

[0243] A hole blocking layer (HBL) can 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 contains a phosphorescent dopant, the HBL can also have a triplet exciton blocking function. The hole blocking layer can be an organic semiconductor layer prepared according to the method of the present invention as defined herein.

[0244] HBL can also be named as auxiliary ETL or a-ETL.

[0245] When the HBL is formed using vacuum deposition or spin coating, the conditions for deposition and coating may be similar to those for forming the HIL. However, the conditions for deposition and coating may vary according to the compound used to form the HBL. Any compound commonly used to form the HBL may be used. Examples of compounds used to form the HBL include Oxadiazole derivatives, triazole derivatives and phenanthroline derivatives.

[0246] The thickness of the HBL may be in the range of about 5 nm to about 100 nm, for example, about 10 nm to about 30 nm. When the thickness of the HBL is within the range, the HBL may have excellent hole blocking properties without substantially deteriorating driving voltage.

[0247] Electron Transport Layer (ETL)

[0248] The organic electronic device according to the present invention may further comprise an electron transport layer (ETL). According to a preferred embodiment of the present invention, the electron transport layer may be an organic semiconductor layer prepared according to the method of the present invention as defined herein.

[0249] According to various embodiments, an organic electronic device may include an electron transport layer or an electron transport layer stack including at least a first electron transport layer and at least a second electron transport layer.

[0250] By properly 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. Therefore, the OLED can have a long lifespan.

[0251] The electron transport layer of the organic electronic device may be an organic semiconductor layer prepared according to the method of the present invention as defined herein. In addition to or instead of the first organic compound and the metal borate compound used to prepare the organic semiconductor layer, the electron transport layer may contain another electron transport material known in the art. Similarly, the electron transport layer may consist of the first organic compound and the metal borate compound used to prepare the organic semiconductor layer. In the case where the organic electronic device of the present invention includes more than one electron transport layer, one or more than one electron transport layer may be an organic semiconductor layer prepared by the method described herein.

[0252] Electron injection layer (EIL)

[0253] An optional EIL that can facilitate electron injection from the cathode can be formed on the ETL, preferably directly on the electron transport layer. Examples of materials for forming the EIL include 8-hydroxyquinoline lithium (LiQ), LiF, NaCl, CsF, Li2O, BaO, Ca, Ba, Yb, Mg known in the art. The deposition and coating conditions for forming the EIL are similar to those for forming the HIL, but the deposition and coating conditions can vary depending on the material for forming the EIL. The EIL can be an organic semiconductor layer prepared according to the method of the present invention as defined herein.

[0254] The thickness of the EIL may be in the range of about 0.1 nm to about 10 nm, for example, in the range of about 0.5 nm to about 9 nm. When the thickness of the EIL is within the range, the EIL may have satisfactory electron injection properties without substantially deteriorating driving voltage.

[0255] Cathode electrode

[0256] If there is an EIL, the 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), aluminum (Al)-lithium (Li), calcium (Ca), barium (Ba), ytterbium (Yb), magnesium (Mg)-indium (In), magnesium (Mg)-silver (Ag), etc. Alternatively, the cathode electrode may be formed of a transparent conductive oxide such as ITO or IZO.

[0257] The thickness of the cathode electrode may be in the range of about 5 nm to about 1000 nm, for example, in the range of about 10 nm to about 100 nm. When the thickness of the cathode electrode is in the range of about 5 nm to about 50 nm, the cathode electrode may be transparent or translucent even if formed of a metal or a metal alloy.

[0258] It is to be understood that the cathode electrode is not part of the electron injection layer or the electron transport layer.

[0259] Charge generation layer / hole generation layer

[0260] The charge generation layer (CGL) may include a p-type layer and an n-type layer. An intermediate layer may be disposed between the p-type layer and the n-type layer.

[0261] Typically, 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 adjacent layer in the anode direction. Similarly, the p-side of the pn junction generates holes and injects them into the adjacent layer in the cathode direction.

[0262] The charge generation layer is used in a tandem and stacked device, for example, in a tandem OLED comprising two or more light-emitting layers between two electrodes. The stacked device may include two or more light-emitting layers. In a tandem OLED comprising two light-emitting layers, the n-type charge generation layer provides electrons to a first light-emitting layer arranged near the anode, and the hole generation layer provides holes to a second light-emitting layer arranged between the first light-emitting layer and the cathode.

[0263] Suitable host materials for the hole generation layer may be materials conventionally used as hole injection and / or hole transport host materials. Moreover, conventional materials may be used as p-type dopants for the hole generation layer. For example, the p-type dopant may be one selected from the following: tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), derivatives of tetracyanoquinodimethane, axialene derivatives, iodine, FeCl3, FeF3, and SbCl5. In addition, the host may be one selected from the following: N,N'-di(naphthalene-1-yl)-N,N-diphenyl-benzidine (NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1-biphenyl-4,4'-diamine (TPD), and N,N',N'-tetranaphthyl-benzidine (TNB). The p-type charge generation layer may be composed of CNHAT.

[0264] The n-type charge generation layer may be a layer prepared according to the method of the present invention as defined herein. The n-type charge generation layer may be a layer of a pure n-type dopant, such as a layer of an electropositive metal, or may be composed of an organic matrix material doped with an n-type dopant. In one embodiment, the n-type dopant may be an alkali metal, an alkali metal compound, an alkaline earth metal, an alkaline earth metal compound, a transition metal, a transition metal compound, or a rare earth metal. In another embodiment, the metal may be one selected from the following: 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 following: Cs, K, Rb, Mg, Na, Ca, Sr, Eu, and Yb. The matrix material suitable for the electron generation layer may be a material conventionally used as a matrix material for an electron injection or electron transport layer. The matrix material may be, for example, one selected from the following: a triazine compound, a hydroxyquinoline derivative such as tris (8-hydroxyquinoline) aluminum, a benzoxazole derivative, and a silacyclopentane derivative.

[0265] The hole generation layer is arranged in direct contact with the n-type charge generation layer.

[0266] Hereinafter, the embodiments are described in more detail with reference to examples. However, the present disclosure is not limited to the following examples. Reference will now be made in detail to the exemplary aspects.

[0267] Details and definitions of the invention

[0268] In this specification, when no definition is provided otherwise, "alkyl group" may refer to an aliphatic hydrocarbon group. An alkyl group may refer to a "saturated alkyl group" without any double or triple bonds. The term "alkyl" as used herein shall encompass straight chain as well as branched and cyclic alkyl groups. For example, a C3-alkyl group may be selected from n-propyl and isopropyl. Similarly, a C4-alkyl group encompasses n-butyl, sec-butyl and tert-butyl. Similarly, a C6-alkyl group encompasses n-hexyl and cyclohexyl.

[0269] C n The subscript number n in refers to the total number of carbon atoms in the corresponding alkyl, arylene, heteroarylene or aryl group.

[0270] As used herein, the term "aryl, corresponding arylidene" shall encompass phenyl (corresponding phenylidene) and fused aromatic groups, such as naphthyl, anthracenyl, phenanthrenyl, tetraphenylene (corresponding naphthracene, anthracene, phenanthrenyl, tetraphenylene, etc.). Aryl groups in which two or more of the above moieties are linked by a single bond, such as biphenyl (sub-unit) and oligo- or polyphenyl (sub-unit), such as tetraphenyl (sub-unit), etc. are not encompassed. Heteroaryl (sub-) groups referred to herein refer to aryl groups as defined above, wherein at least one carbon atom is substituted by a heteroatom, preferably selected from N, O, S, B or Si.

[0271] The term "fused aryl (sub) radical group" refers to an aryl group comprising at least two aromatic rings, which are fused to each other by sharing two carbon atoms with each other. In this respect, it can be specified that the fused aryl group (or fused aryl subyl group) comprises more than two condensed rings, wherein each ring is fused to at least one other aromatic ring of the fused aryl (sub) radical by sharing two carbon atoms with one (or more) other rings of the fused aryl (sub) radical. The limiting examples of this fused aryl group are naphthyl, anthracenyl, fluorenyl, phenanthrenyl, fluoranthenyl etc.

[0272] As used herein, the term "alkenyl" refers to a group containing a carbon-carbon double bond -CR 1 =CR 2 R 3 .

[0273] The term "perhalo" as used herein refers to a hydrocarbyl group wherein all hydrogen atoms in the hydrocarbyl group are replaced by halogen (F, Cl, Br, I) atoms.

[0274] The term "alkoxy" as used herein refers to a structural fragment of the formula -OR, wherein R is a hydrocarbon group, preferably an alkyl group or a cyclic alkyl group.

[0275] C n The subscript number n in the -heteroaryl group refers only to the number of carbon atoms in addition to the number of heteroatoms. In this context, it is clear that a C3 heteroaryl group is an aromatic compound containing three carbon atoms, such as pyrazole, imidazole, Azoles, thiazoles, etc.

[0276] In the present specification, the single bond refers to a single bond.

[0277] The term "fluorinated" as used herein refers to a hydrocarbon group in which at least one hydrogen atom contained in the hydrocarbon group is substituted by a fluorine atom. A fluorinated group in which all hydrogen atoms are substituted by fluorine atoms is called a perfluorinated group and is particularly represented by the term "fluorinated".

[0278] For the purposes of the present invention, a group is "substituted" by another group if one of the hydrogen atoms contained in the group is replaced by another group, wherein the other group is a substituent.

[0279] For the purposes of the present invention, the expression "between" with respect to a layer being between two other layers does not exclude the presence of a further layer that may be arranged between this layer and one of the two other layers. For the purposes of the present invention, the expression "in direct contact" with respect to two layers being in direct contact with each other means that no further layer is arranged between these two layers. A layer deposited on top of another layer is considered to be in direct contact with said layer.

[0280] With regard to the organic semiconductor layer of the invention and with regard to the compounds of the invention, the compounds mentioned in the experimental part are most preferred.

[0281] 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). A lighting device may be any device for lighting, irradiating, signaling or projecting. They are accordingly classified as lighting devices, irradiating devices, signaling devices and projecting devices. A lighting device generally consists of a light radiation source, a device for transmitting the radiation flux into space in a desired direction, and a housing that connects the components into a single device and protects the radiation source and the light transmission system from damage and environmental influences.

[0282] The terms "OLED" and "organic light emitting diode" are used concurrently and have the same meaning. The term "organic electroluminescent device" as used herein may include both organic light emitting diodes as well as organic light emitting transistors (OLETs).

[0283] Organic electroluminescent devices (OLEDs) can be bottom-emitting devices or top-emitting devices.

[0284] Devices comprising organic light emitting diodes are, for example, displays or lighting panels.

[0285] In the present invention, with respect to the following defined terms, unless a different definition is given in the claims or elsewhere in this specification, these defined terms shall apply.

[0286] In the context of the present specification, the term "different" or "different from" in relation to a host material means that the host material differs in its structural formula.

[0287] The terms "light-emitting layer" and "light-emitting layer" are used simultaneously and have the same meaning.

[0288] As used herein, "weight percent", "wt.-%", "percent by weight", "wt. %" and variations thereof refer to a composition, component, substance or agent expressed as the weight of the component, substance or agent of the corresponding electron transport layer divided by the total weight of its corresponding electron transport layer, multiplied by 100. It is understood that the amount of the total weight percentage of all components, substances and agents of the corresponding electron transport layer and electron injection layer is selected so that it does not exceed 100 wt. %.

[0289] As used herein, "volume percent", "vol.-%, "percent by volume", "volume %" and variations thereof refer to a composition, component, substance or agent expressed as the volume of the component, substance or agent of the corresponding electron transport layer divided by the total volume of its corresponding electron transport layer, multiplied by 100. It is understood that the amount of the total volume percentage of all components, substances and agents of the cathode layer is selected so that it does not exceed 100 volume %.

[0290] All numerical values ​​herein are assumed to be modified by the term "about", whether or not explicitly stated. As used herein, the term "about" refers to the variation in numerical amounts that may occur. Whether or not modified by the term "about", the claims include equivalents of the amounts.

[0291] It should be noted that as used in the specification and claims, the singular forms "a," "an," "the," and "said" include plural referents unless the content clearly dictates otherwise.

[0292] The terms "does not contain", "does not contain", "does not include" do not exclude impurities. Impurities have no technical effect on the purpose achieved by the present invention.

[0293] In the context of this specification, the term "substantially non-luminescent" or "non-luminescent" means that the contribution of a compound or layer to the visible luminescence spectrum from a device is less than 10%, preferably less than 5%, relative to the visible luminescence spectrum. The visible luminescence spectrum is a luminescence spectrum having a wavelength of about ≥380 nm to about ≤780 nm.

[0294] The working voltage, also called U, is 10 mA / cm2. 2 ) is measured in volts (V).

[0295] Candela / ampere efficiency, also known as cd / A efficiency, is measured at 10 mA / cm2. 2 ) are measured in candela per ampere.

[0296] External quantum efficiency (also called EQE) is measured as a percentage (%).

[0297] The color space is described by the coordinates CIE-x and CIE-y (International Commission on Illumination 1931). For blue luminescence, CIE-y is particularly important. A smaller CIE-y indicates a darker blue.

[0298] The highest occupied molecular orbital, also known as the HOMO, and the lowest unoccupied molecular orbital, also known as the LUMO, are measured in electron volts (eV).

[0299] The terms "OLED", "organic light emitting diode", "organic light emitting device", "organic optoelectronic device" and "organic light emitting diode" are used concurrently and have the same meaning.

[0300] The terms "lifetime" and "service life" are used concurrently and have the same meaning.

[0301] The anode electrode and the cathode electrode may be described as anode electrode / cathode electrode or anode / cathode or anode electrode layer / cathode electrode layer.

[0302] Room temperature, also called ambient temperature, is 23°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0303] These and / or other aspects and advantages of the present invention will become apparent and more readily understood from the following description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0304] Figure 1 is a schematic cross-sectional view of an organic light emitting diode (OLED) according to an exemplary embodiment of the present invention;

[0305] Figure 2 is a schematic cross-sectional view of an OLED according to an exemplary embodiment of the present invention;

[0306] Figure 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;

[0307] Figure 4 Shown is a graph in which the amount of the first composition remaining in the VTE source in wt % is plotted against the concentration of the compound in the first composition in wt %. DETAILED DESCRIPTION

[0308] Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The exemplary embodiments are described below, by referring to the drawings, to explain aspects of the present invention.

[0309] In this document, when a first element is referred to as being formed or disposed "on" or "over" a second element, the first element may be directly disposed on the second element, or one or more other elements may be disposed between them. When a first element is referred to as being "formed or disposed directly on" or "formed or disposed directly over" a second element, there are no other elements between them.

[0310] Figure 11 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. The electron transport layer (ETL) 160 is formed on the EML 150. The electron injection layer (EIL) 180 is disposed on the electron transport layer (ETL) 160. The cathode 190 is directly disposed on the electron injection layer (EIL) 180.

[0311] Instead of a single electron transport layer 160, a stack of electron transport layers (ETL) may optionally be used.

[0312] Figure 2 is a schematic cross-sectional view of an OLED 100 according to another exemplary embodiment of the present invention. Figure 2 and Figure 1 The difference is that Figure 2 The OLED 100 includes an electron blocking layer (EBL) 145 and a hole blocking layer (HBL) 155 .

[0313] Reference Figure 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 electrode 190.

[0314] Preferably, the organic semiconductor layer including the first composition may be an ETL.

[0315] Figure 3 is a schematic cross-sectional view of a tandem OLED 200 according to another exemplary embodiment of the present invention. Figure 3 and Figure 2 The difference is Figure 3 The OLED 100 further includes a charge generation layer (CGL) and a second light emitting layer (151).

[0316] Reference Figure 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; 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.

[0317] Preferably, the organic semiconductor layer including the first composition may be the first ETL and / or the second ETL.

[0318] Although not in Figure 1 , Figure 2 and Figure 3 1 , but 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 made thereto.

[0319] Hereinafter, one or more exemplary embodiments of the present invention will be described in detail with reference to the following examples. However, these examples are not intended to limit the purpose and scope of one or more exemplary embodiments of the present invention.

[0320] Melting point

[0321] The melting point (mp) was determined as the peak temperature of the DSC curve from the above TGA-DSC measurement or from a separate DSC measurement (Mettler Toledo DSC822e, the sample was heated from room temperature to complete melting at a heating rate of 10 K / min under a pure nitrogen flow. An amount of 4 to 6 mg of the sample was placed in a 40 μL Mettler Toledo aluminum pan with a lid and a hole of <1 mm was punched in the lid).

[0322] Glass transition temperature

[0323] The glass transition temperature (Tg) was measured as described in DIN EN ISO 11357, published in March 2010, in a Mettler Toledo DSC 822e differential scanning calorimeter under nitrogen and using a heating rate of 10 K / min.

[0324] Standard starting temperature

[0325] Standard starting temperature (TRO ) is determined by loading 100 mg of the compound into a VTE source. As a VTE source, a point source of organic material supplied by Kurt J. Lesker Company (www.lesker.com) or CreaPhys GmbH (http: / / www.creaphys.com) can be used. -5 The VTE source was heated at a constant rate of 15 K / min at a pressure of 100 mbar and the temperature inside the source was measured with a thermocouple. The evaporation of the compound was detected with a QCM detector, which detected the deposition of the compound on the quartz crystal of the detector. The deposition rate on the quartz crystal was / sec. To determine the standard onset temperature, the deposition rate is plotted against the VTE source temperature. The standard onset is the temperature at which significant deposition occurs on the QCM detector. To obtain accurate results, the VTE source is heated and cooled three times, and only the results from the second and third runs are used to determine the standard onset temperature.

[0326] In order to achieve good control of the evaporation rate of the organic compound, the standard starting temperature may be in the range of 200°C to 255°C. If the standard starting temperature is below 200°C, the evaporation may be too fast and thus difficult to control. If the standard starting temperature is above 255°C, the evaporation rate may be too low, which may result in a low cycle time and the organic compounds in the VTE source may decompose due to prolonged exposure to high temperatures.

[0327] The standard onset temperature is an indirect measure of the volatility of a compound. The higher the standard onset temperature, the lower the volatility of the compound.

[0328] According to another embodiment, the difference between the standard onset temperatures of the first organic compound and the metal borate compound is less than 60K, or less than 50K, or less than 40K.

[0329] Therefore, the uniformity of the organic semiconductor layer prepared by the method according to the present invention can be improved.

[0330] Reduction potential

[0331] The reduction potential was determined at room temperature by cyclic voltammetry using a constant potential device Metrohm PGSTAT30 and software MetrohmAutolab GPES. The redox potential given under a specific compound is measured as follows: in a dry 0.1M THF solution of the test substance degassed with argon, under an argon atmosphere, a 0.1M tetrabutylammonium hexafluorophosphate supporting electrolyte was used between platinum working electrodes, and a pseudo-standard electrode (Metrohm silver rod electrode) consisting of a silver wire covered with silver chloride and directly immersed in the measurement solution was measured at a scan rate of 100mV / s. The first run was completed within the widest potential range set on the working electrode, and the range was then appropriately adjusted in subsequent runs. The last three runs were completed when ferrocene (0.1M concentration) was added as a standard. The potential average corresponding to the cathode and anode peaks of the studied compound was measured after subtracting the potential average for the standard Fc + The values ​​reported above were finally provided after averaging the cathodic and anodic potentials observed for the α / Fc redox couple. All investigated compounds as well as the reported comparative compounds showed clear reversible electrochemical behavior.

[0332] Calculated HOMO and LUMO

[0333] HOMO and LUMO were calculated using the program package TURBOMOLE V6.5. The optimized geometry of the molecular structure as well as the HOMO and LUMO energy levels were determined by applying the hybrid functional B3LYP and 6-31G* basis set in the gas phase. If more than one conformation was feasible, the one with the lowest total energy was selected.

[0334] Preparation of the first composition

[0335] The first organic compound and the metal borate compound can be prepared by methods known in the art.

[0336] In Table 1, the properties of the first organic compounds that can be suitably used are shown.

[0337] The first composition can be prepared by mixing the first organic compound and the metal borate compound in a solid state and then -3 Up to 10 -7 Prepared by evaporation and condensation at a pressure of mbar.

[0338] In Table 2, a first composition that can be suitably used is shown. The metal borate compound of formula (2a) can be referred to as Li-1, and the metal borate compound of formula (2b) can be referred to as Li-2.

[0339] Preparation of the second organic compound

[0340] The second organic compound can be prepared by a method known in the art. In Table 3, examples of the second organic compound are shown.

[0341] Pure electron carrier device (EOD)

[0342] In order to indirectly measure the conductivity of the organic semiconductor layer prepared by the method according to the present invention, Pure Electronics Carrier Devices The operating voltage is measured. At a given current density, the lower the operating voltage, the higher the conductivity of the organic semiconductor layer.

[0343] In order to prepare the Example 1 and Comparative Example 1 in Table 4 Pure electron carrier devices , the glass substrate was cut into a size of 50 mm×50 mm×0.7 mm, ultrasonically cleaned with isopropyl alcohol for 5 minutes, then ultrasonically cleaned with pure water for 5 minutes, and then cleaned with UV ozone for 30 minutes.

[0344] Then, at 10 -5 Up to 10 -7 11 nm Mg:Ag alloy (90:10 volume %) was deposited on a glass substrate at a pressure of 100 mbar to form a first electrode.

[0345] Then, dimethyl (3- (10- (naphthalene-2-yl) anthracene-9-yl) phenyl) phosphine oxide (also referred to as ETM-1) as the second organic compound and the first composition C-1 (see Example 1 in Table 4) or Li-1 (see Comparative Example 1) were co-deposited on the first electrode to form a first organic semiconductor layer having a thickness of 17 nm. The concentration of the compound in the layer can be obtained from Table 4.

[0346] Then, a second organic semiconductor layer including the first composition (see Example 1 in Table 4) or Li-1 (see Comparative Example 1) was deposited on the first organic semiconductor layer to form the second organic semiconductor layer. The thickness of the second organic semiconductor layer can be obtained from Table 4.

[0347] Then, dimethyl (3- (10- (naphthalene-2-yl) anthracene-9-yl) phenyl) phosphine oxide (also referred to as ETM-1) as the second organic compound and the first composition C-1 (see Example 1 in Table 4) or lithium tetrakis (1H-pyrazol-1-yl) borate (also referred to as Li-1), see Comparative Example 1, were co-deposited on the second organic semiconductor layer to form a third organic semiconductor layer having a thickness of 17 nm. The concentration of the compound in the layer can be obtained from Table 4.

[0348] Then, at 10 -5 Up to 10 -7 11 nm Mg:Ag alloy (90:10 volume %) was deposited on the third organic semiconductor layer at a pressure of 200 mbar to form a second electrode.

[0349] The operating voltage is determined as described below for OLEDs.

[0350] General process of manufacturing OLED

[0351] For the top-emitting device, Examples 2 to 6 in Table 5, the glass substrate was cut into a size of 50 mm×50 mm×0.7 mm, ultrasonically cleaned with isopropyl alcohol for 5 minutes, then ultrasonically cleaned with pure water for 5 minutes, and then cleaned with UV ozone for 30 minutes. -5 mbar to 10 -7 100 nm Ag was deposited on a glass substrate at a pressure of 100 mbar to form an anode.

[0352] Then, 92 vol% of biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-amine (CAS 1242056-42-3) and 8 vol% of 2,2',2"-(cyclopropane-1,2,3-triylidene)tris(2-p-cyanotetrafluorophenyl)acetonitrile) were vacuum deposited on the anode to form a HIL having a thickness of 10 nm. Then, biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-amine was vacuum deposited on the HIL to form a HTL having a thickness of 118 nm.

[0353] Then, for Examples 2 and 3, N,N-bis(4-(dibenzo[b,d]furan-4-yl)phenyl)-[1,1':4',1"-terphenyl]-4-amine (CAS 1198399-61-9) was vacuum deposited on the HTL to form an electron blocking layer (EBL) having a thickness of 5 nm. For Examples 4 to 6, N-(4-(dibenzo[b,d]furan-4-yl)phenyl)-N-(4-(9-phenyl-9H-fluoren-9-yl)phenyl)-[1,1'-biphenyl]-4-amine (CAS 1824678-59-2) was vacuum deposited on the HTL to form an electron blocking layer (EBL) having a thickness of 5 nm.

[0354] Subsequently, 97 vol% H09 (Sun Fine Chemicals, Korea) as an EML host and 3 vol% BD200 (Sun Fine Chemicals, Korea) as a fluorescent blue dopant were deposited on the EBL to form a blue-light-emitting EML with a thickness of 20 nm.

[0355] Then, an auxiliary ETL having a thickness of 5 nm was formed by depositing 2-(3′-(9,9-dimethyl-9H-fluoren-2-yl)-[1,1′-biphenyl]-3-yl)-4,6-diphenyl-1,3,5-triazine (CAS 1955543-57-3) on the light emitting layer (EML).

[0356] Then, an electron transport layer having a thickness of 31 nm was formed on the auxiliary electron transport layer according to Examples 2 to 6 (see Table 5).

[0357] Then, an electron injection layer with a thickness of 2 nm was formed on the electron transport layer by depositing Yb.

[0358] In 10 -7 mbar to Mg:Ag alloy (90:10 volume %) was evaporated at a rate of 1:1 to form a cathode with a thickness of 13 nm.

[0359] A covering layer of biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine was formed on the cathode with a thickness of 75 nm.

[0360] The OLED stack is protected from environmental conditions by encapsulating the device with a glass slide. Thus, a cavity is formed which also includes a getter material for protection.

[0361] To evaluate the performance of the inventive examples compared to the prior art, current efficiency was measured at 20°C. The current-voltage characteristics were determined using a Keithley 2635 source measurement unit by providing a voltage in V and measuring the current in mA flowing through the device under test. The voltage applied to the device was varied between 0 V and 10 V in steps of 0.1 V. Similarly, the brightness-voltage characteristics and CIE coordinates were measured by using an Instrument Systems CAS-140CT array spectrometer to measure brightness (cd / m 2 ) is determined for each voltage value. 10 mA / cm is determined by interpolating the brightness-voltage and current-voltage characteristics, respectively. 2 cd / A efficiency under .

[0362] A Keithley 2400 source meter was used at ambient conditions (20°C) and 30 mA / cm 2 The lifetime LT of the device is measured and recorded in hours.

[0363] The brightness of the device is measured using a calibrated photodiode. The lifetime LT is defined as the time until the brightness of the device decreases to 97% of its initial value.

[0364] For top-emitting devices, at 10 mA / cm 2 The light output in terms of external efficiency EQE and power efficiency (lm / W efficiency) was determined below.

[0365] To determine the efficiency EQE in %, the light output of the device was measured using a calibrated photodiode.

[0366] To determine the power efficiency in lm / W, in a first step the power efficiency in candela / m2 (cd / m 2 In a second step, the brightness is then multiplied by π and divided by the voltage and current density.

[0367] Table 1: Examples of the first organic compound

[0368]

[0369]

[0370]

[0371]

[0372] 1) Not observed; 2) Not determined.

[0373] Table 2: Examples of the first composition

[0374]

[0375] Table 3: Examples of second organic compounds

[0376]

[0377] Stability of the first composition over time

[0378] In order to examine the stability of the first composition over time, a first composition consisting of 75 wt % of the first organic compound and 25 wt % of the metal borate compound was loaded into a VTE source and -5 Up to 10 -7 The mixture was evaporated at 100 mbar until 64 wt% of the content of the VTE source was evaporated. Figure 4 As can be seen in FIG. 1 , the ratio of the first organic compound (solid line) to the metal borate compound (dashed line) does not change significantly over time.

[0379]

[0380]

[0381] Technical Effects of the Invention

[0382] The operating voltage of the EOD is shown in Table 4, wherein the second organic semiconductor layer has a thickness of 0 nm to 3 nm.

[0383] In Comparative Example 1, the first organic semiconductor layer and the third organic semiconductor layer contain the second organic compound and the metal borate compound Li-1. The second organic semiconductor layer is composed of the metal borate compound Li-1. The operating voltage increases as the thickness of the second organic semiconductor layer increases. At 0 nm, the operating voltage is 0.3 V, and at 3 nm, the operating voltage is 3.7 V, see Table 4.

[0384] In Example 1, the first organic semiconductor layer and the third organic semiconductor layer comprise the second organic compound and the first composition C-1. The second organic semiconductor layer consists of the first composition C-1. At 0 nm, the operating voltage is 0.5 V. The operating voltage is comparable to that of Comparative Example 1. At 3 nm, the operating voltage is 0.5 V. Therefore, the operating voltage of the device including the organic semiconductor layer according to the present invention is significantly lower than that of Comparative Example 1.

[0385] The operating voltage is an indication of the conductivity of the semiconductor layer. The higher the conductivity, the lower the operating voltage.

[0386] In summary, the organic semiconductor layer produced by the method according to the invention has greatly improved conductivity compared to the prior art.

[0387] In Table 5 the properties of OLEDs comprising an organic semiconductor layer produced according to the invention are shown.

[0388] As can be seen in Examples 2 to 6, when the organic semiconductor layer is prepared according to the present invention, very good operating voltage, cd / A efficiency and lifetime can be obtained.

[0389] In summary, an organic electronic device comprising an organic semiconductor layer produced by the method according to the invention shows very good properties, in particular operating voltage, cd / A efficiency and / or lifetime.

[0390] The features disclosed in the above description and in the dependent claims may, both individually and in any combination thereof, thereby in their various forms as material for realizing the aspects of the disclosure set out in the independent claims.

Claims

1. A method for preparing an organic semiconductor layer, the method comprising the following steps: a) providing a first composition in a first vacuum thermal evaporation source, wherein the first composition comprises: aa) a first organic compound, the first organic compound comprising at least one unsubstituted or substituted C 10 To C 30 A fused aryl group and / or at least one unsubstituted or substituted C3 to C 30 A heteroaryl group wherein one or more substituents, if present, are independently selected from the group consisting of: (i) deuterium, (ii) halogen, (iii) C1 to C 22 Silyl group, (iv) C1 to C 30 Alkyl group, (v) C1 to C 10 Alkylsilyl group, (vi) C6 to C 22 Arylsilyl group, (vii) C3 to C 30 Cyclic alkyl group, (viii) C2 to C 30 Heterocyclic alkyl group, (ix) C6 to C 30 Aryl group, (x) C2 to C 30 Heteroaryl group, (xi) C1 to C 30 perfluoroalkyl group, and (xii) C1 to C 10 trifluoroalkyl group, wherein the first organic compound has: i) a dipole moment in the range ≥ 0 Debye and ≤ 2 Debye; and ii) a molecular weight in the range of ≥400 and ≤1,800; and bb) metal borate compounds; b) transforming the first composition from a solid phase to a gas phase in a vacuum chamber, wherein step b) comprises the further step of: converting the first composition from the solid phase into an at least partially molten state before converting into the gas phase; and c) depositing the first composition to form the organic semiconductor layer.

2. The method according to claim 1, wherein the first organic compound comprises at least one selected from C 10 To C 24 Fused aromatic groups and / or C3 to C 24 A group of a heteroaryl group.

3. The method according to claim 1 or 2, wherein the heteroaryl group comprises one to three heteroatoms independently selected from N, O or S.

4. The method according to claim 1, wherein the first organic compound further comprises a group selected from the following: a substituted or unsubstituted spiro[fluorene-9,9'-xanthene]-yl group, a substituted or unsubstituted 9,9'-dimethylfluorenyl group, a substituted or unsubstituted 9,9'-diphenylfluorenyl group, a 9,9'-spiro[difluorenyl]-yl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, a substituted or unsubstituted fluoranthene group, a substituted or unsubstituted group consisting of 3 to 6 connected benzene rings, or a substituted or unsubstituted tetraphenylvinyl group.

5. The method according to claim 1, wherein the first organic compound is represented by Formula 1a in A 1 , A 2 , A 3 and A 4 are independently selected from a single bond, a substituted or unsubstituted C6 to C 18 Aromatic substituent or unsubstituted or substituted C1 to C 18 heteroaromatic subunit; A 5 Selected from unsubstituted or substituted C 10 -C 30 A fused aryl group or a group selected from unsubstituted or substituted C3-C 30 heteroaryl; R 1 To R 5 independently selected from substituted or unsubstituted phenyl; a) to e) are independently selected to be 0 or 1, provided that 2≤a+b+c+d+e≤5; in, In Formula 1a, one or more substituents, if present, are independently selected from: (i) Deuterium, (ii) halogen, (iii) C1 to C 22 Silyl group, (iv) C1 to C 30 Alkyl groups, (v) C1 to C 10 Alkylsilyl group, (vi) C6 to C 22 Arylsilyl group, (vii) C3 to C 30 Cyclic alkyl groups, (viii) C2 to C 30 Heterocyclic alkyl groups, (ix) C6 to C 30 Aryl groups, (x) C2 to C 30 Heteroaryl groups, (xi) C1 to C 30 a perfluoroalkyl group, or (xii) C1 to C 10 trifluoroalkyl group; and / or The first organic compound is represented by Formula 1b in A 1 , A 2 , A 3 and A 4 are independently selected from a single bond, a substituted or unsubstituted C6 to C 18 Aromatic substituent or unsubstituted or substituted C1 to C 18 heteroaromatic subunit; A 5 Selected from unsubstituted or substituted C 10 To C 30 A fused aryl group or a group selected from unsubstituted or substituted C3 to C 30 heteroaryl; R 1 To R 3 independently selected from substituted or unsubstituted phenyl; Wherein, in Formula 1b, one or more substituents, if present, are independently selected from the following: (i) deuterium, (ii) halogen, (iii) C1 to C 22 Silyl group, (iv) C1 to C 30 Alkyl groups, (v) C1 to C 10 Alkylsilyl group, (vi) C6 to C 22 Arylsilyl group, (vii) C3 to C 30 Cyclic alkyl groups, (viii) C2 to C 30 Heterocyclic alkyl groups, (ix) C6 to C 30 Aryl groups, (x) C2 to C 30 Heteroaryl groups, (xi) C1 to C 30 Perfluoroalkyl groups, (xii) C1 to C 10 trifluoroalkyl group; and / or The first organic compound can be represented by Formula 1c *-A 1 -A 2 -A 3 -A 4 -A 5 (1c), in The compound of formula (1c) comprises a part -A 1 -A 2 -A 3 -A 4 -A 5 , where the asterisk symbol "*" marks the part -A 1 -A 2 -A 3 -A 4 -A 5 possible bonding sites to the rest of the structure; A 1 , A 2 , A 3 and A 4 are independently selected from a single bond, a substituted or unsubstituted C6 to C 18 Aromatic substituent or unsubstituted or substituted C1 to C 18 heteroaromatic subunit; A 5 Selected from unsubstituted or substituted C 10 To C 30 A fused aryl group or a group selected from unsubstituted or substituted C3 to C 30 heteroaryl; Wherein, in Formula 1c, one or more substituents, if present, are independently selected from the following: (i) deuterium, (ii) halogen, (iii) C1 to C 22 Silyl group, (iv) C1 to C 30 Alkyl groups, (v) C1 to C 10 Alkylsilyl group, (vi) C6 to C 22 Arylsilyl group, (vii) C3 to C 30 Cyclic alkyl groups, (viii) C2 to C 30 Heterocyclic alkyl groups, (ix) C6 to C 30 Aryl groups, (x) C2 to C 30 Heteroaryl groups, (xi) C1 to C 30 Perfluoroalkyl groups, (xii) C1 to C 10 trifluoroalkyl group; and / or The first organic compound can be represented by Formula 1d *-A 1 -A 2 -A 3 -A 4 -A 5 (1d) in The compound of formula (1d) comprises a part -A 1 -A 2 -A 3 -A 4 -A 5 , where the asterisk symbol "*" marks the part -A 1 -A 2 -A 3 -A 4 -A 5 possible bonding sites to the rest of the structure; Y 1 is selected from a single bond, O, S, CR2 or SiR2, wherein R is independently selected from C1 to C 12 Alkyl or C6 to C 18 Aryl; A 1 , A 2 , A 3 and A 4 are independently selected from a single bond, a substituted or unsubstituted C6 to C 18 Aromatic substituent or unsubstituted or substituted C1 to C 18 heteroaromatic subunit; A 5 Selected from unsubstituted or substituted C 10 To C 30 A fused aryl group or a group selected from unsubstituted or substituted C3 to C 30 heteroaryl; Wherein, in Formula 1d, one or more substituents, if present, are independently selected from the following: (i) deuterium, (ii) halogen, (iii) C1 to C 22 Silyl group, (iv) C1 to C 30 Alkyl groups, (v) C1 to C 10 Alkylsilyl group, (vi) C6 to C 22 Arylsilyl group, (vii) C3 to C 30 Cyclic alkyl groups, (viii) C2 to C 30 Heterocyclic alkyl groups, (ix) C6 to C 30 Aryl groups, (x) C2 to C 30 Heteroaryl groups, (xi) C1 to C 30 Perfluoroalkyl groups, (xii) C1 to C 10 A trifluoroalkyl group.

6. The method of claim 1, wherein the metal borate compound is an alkali metal borate, an alkaline earth metal borate, or a rare earth metal borate, the metal borate compound having a molecular weight in the range of ≥100 to ≤1,200.

7. The method according to claim 1, wherein the metal borate compound has the following formula: Where M is a metal ion, A 6 To A 9 Each of which is independently selected from H, substituted or unsubstituted C6-C 20 Aryl and substituted or unsubstituted C2-C 20 heteroaryl, and n is the valence of the metal ion.

8. The method according to claim 1, further comprising the steps of: e) providing a second organic compound in a second vacuum thermal evaporation source; f) converting the second organic compound from a solid phase to a gas phase in the vacuum chamber; and g) depositing the first composition together with the second organic compound to form the organic semiconductor layer.

9. The method of claim 8, wherein the second organic compound has a dipole moment in the range of ≥ 1.5 Debye and ≤ 10 Debye; and a molecular weight in the range of ≥ 400 and ≤ 1,800.

10. The method according to claim 8, wherein the second organic compound comprises at least one group selected from the group consisting of: phenanthroline; benzimidazole; pyridin-4-yl; pyrimidine; quinoline; benzoquinoline; dibenzoquinoline; quinoxaline; benzoquinoxaline; dibenzoquinoxaline; xanthene; C=O; COOR, wherein R is selected from the group consisting of C1-C 12 Alkyl or C6-C 18 Aryl; and P=X, wherein X is selected from O, S or Se.

11. An organic electronic device comprising an anode, a cathode and an organic semiconductor layer obtainable by a method according to any one of the preceding claims.

12. A method for preparing an organic electronic device, the method comprising the step of preparing an organic semiconductor layer according to the method according to any one of claims 1 to 10.

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