WO2022082990A1 - 有机电致发光器件和显示装置 - Google Patents

有机电致发光器件和显示装置 Download PDF

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WO2022082990A1
WO2022082990A1 PCT/CN2020/138927 CN2020138927W WO2022082990A1 WO 2022082990 A1 WO2022082990 A1 WO 2022082990A1 CN 2020138927 W CN2020138927 W CN 2020138927W WO 2022082990 A1 WO2022082990 A1 WO 2022082990A1
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layer
blocking layer
homo
host
light
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PCT/CN2020/138927
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English (en)
French (fr)
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邱丽霞
陈磊
刘杨
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京东方科技集团股份有限公司
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Priority to CN202080003591.1A priority Critical patent/CN114667291A/zh
Priority to US17/429,359 priority patent/US20220320455A1/en
Publication of WO2022082990A1 publication Critical patent/WO2022082990A1/zh

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Definitions

  • the present disclosure relates to, but is not limited to, the field of display technology, and in particular, to an organic electroluminescence device and a display device.
  • OLED Organic Light Emitting Device
  • OLED is an active light-emitting device, which has the advantages of high brightness, color saturation, ultra-thin, wide viewing angle, low power consumption, extremely high response speed and flexibility, and is widely used in in the field of flat panel displays.
  • OLED includes an anode, a cathode, and a light-emitting layer arranged between the anode and the cathode.
  • the light-emitting principle is to inject holes and electrons into the light-emitting layer from the anode and the cathode, respectively.
  • the electrons and holes meet in the light-emitting layer, the electrons and The holes recombine to generate excitons, which emit light while transitioning from an excited state to a ground state.
  • An organic electroluminescence device comprising an anode, a cathode, and a light-emitting layer disposed between the anode and the cathode, the light-emitting layer comprising a host material and a guest material doped in the host material; the host material and the object material satisfy:
  • HOMO Dopant is the highest occupied molecular orbital HOMO energy level of the guest material
  • HOMO Host is the HOMO energy level of the host material
  • LUMO Dopant is the lowest unoccupied molecular orbital LUMO energy level of the guest material
  • LUMO host is the The LUMO energy level of the host material.
  • a hole blocking layer is further disposed between the light-emitting layer and the cathode, and the host material, the guest material and the hole blocking layer satisfy:
  • HOMO HBL is the HOMO energy level of the hole blocking layer.
  • the guest material and hole blocking layer satisfy:
  • the host material and hole blocking layer satisfy:
  • E HBL is the electron mobility of the hole blocking layer
  • E host is the electron mobility of the host material
  • the electron mobility E HBL of the hole blocking layer is 10 -5 cm 2 /Vs to 10 -8 cm 2 /Vs
  • the electron mobility E host of the host material is 10 -6 cm 2 /Vs to 10 -8 cm 2 /Vs.
  • the host material and hole blocking layer satisfy:
  • LUMO HBL is the LUMO energy level of the hole blocking layer.
  • the material of the guest material and the hole blocking layer satisfies:
  • T1 HBL is the lowest triplet energy of the hole blocking layer
  • T1 Dopant is the lowest triplet energy of the guest material
  • a hole transport layer and an electron blocking layer are further provided between the anode and the light emitting layer, and the hole transport layer and the electron blocking layer satisfy:
  • HOMO HTL is the HOMO energy level of the hole transport layer
  • HOMO EBL is the HOMO energy level of the electron blocking layer
  • the electron blocking layer and host material satisfy:
  • the hole transport layer and the electron blocking layer satisfy:
  • EK HTL is the hole mobility of the hole transport layer
  • EK EBL is the hole mobility of the electron blocking layer
  • the hole transport layer has a hole mobility of 10 -4 cm 2 /Vs to 10 -5 cm 2 /Vs
  • the electron blocking layer has a hole mobility of 10 -5 cm 2 /Vs to 10 -7 cm 2 /Vs.
  • the host material includes an anthracene derivative, 9,10-(2-naphthyl)anthracene, or 2-methyl-9,10-(2-naphthyl)anthracene.
  • the host material includes one or more of the following compounds having the following structural formula:
  • the guest material includes a compound having the following structural formula:
  • X is O or S;
  • Y is N-R7, B, P;
  • R1 to R3 are hydrogen, deuterium, fluorine, C1-C4 alkyl, C3-C10 cycloalkyl, C1-C30 alkyl methyl Silyl, or C6-C10 arylsilyl;
  • R4, R5 are hydrogen, deuterium, fluorine, C1-C4 alkyl, C3-C10 cycloalkyl, C1-C30 alkylsilyl, or C6-C30 arylsilyl, substituted or unsubstituted C6-C30 aryl or heteroaryl;
  • Ar 1 and Ar 2 are substituted or unsubstituted C6-C30 aryl or heteroaryl;
  • R1 to R3 is the same or different.
  • the guest material includes one or more of the compounds having the following structural formula:
  • the hole blocking layer includes but is not limited to a compound having the structure shown in the following formula:
  • R1 and R2 are hydrogen, deuterium, fluorine, C1-C4 alkyl, C3-C10 cycloalkyl, C1-C30 alkylsilyl, or C6-C10 arylsilyl;
  • Ar 1 , Ar 2 is a substituted or unsubstituted C6-C30 aryl or heteroaryl group, one of which is a heteroaryl group containing at least one nitrogen;
  • R1 and R2 are the same or different; Ar 1 and Ar 2 are different.
  • the hole blocking layer includes, but is not limited to, a compound having the following structural formula:
  • L is a substituted or unsubstituted C6-C30 aryl or heteroaryl
  • A is a substituted or unsubstituted nitrogen-containing aromatic heterocycle, containing at least one nitrogen atom
  • R1, R2 are methyl, aryl
  • R1 and R2 are the same or different.
  • the hole blocking layer includes one or more compounds having the following structural formula:
  • the material of the electron blocking layer includes, but is not limited to, any one of the compounds having the following structural formula:
  • L1-L3 are single bonds, C6-C15 aryl; Ar 1 , Ar 2 are substituted or unsubstituted C6-C40 aryl, arylamine or fluorenyl, Ar 1 and Ar 2 are different groups .
  • the material of the electron blocking layer includes one or more compounds having the following structural formula:
  • one of Ar 1 and Ar 2 is a substituent represented by the following structural formula:
  • R1-R5 are hydrogen, deuterium, alkyl, cycloalkyl or C6-C36 aryl.
  • one of Ar 1 and Ar 2 is a substituent represented by the following structural formula:
  • a display device includes the aforementioned organic electroluminescence device.
  • FIG. 1 is a schematic structural diagram of an OLED display device
  • FIG. 2 is a schematic plan view of a display substrate
  • 3 is an equivalent circuit diagram of a pixel driving circuit
  • FIG. 4 is a schematic cross-sectional structure diagram of a display substrate
  • FIG. 6 is a schematic diagram of an OLED structure according to an exemplary embodiment of the present disclosure.
  • FIG. 7 is a schematic diagram of an energy level relationship of an OLED structure according to an exemplary embodiment of the present disclosure.
  • FIG. 8 is an electrochemical stability test result of an electron blocking layer according to an exemplary embodiment of the present disclosure.
  • FIG. 9 is an electrochemical stability test result of another electron blocking layer according to an exemplary embodiment of the present disclosure.
  • FIG. 10 is a schematic diagram of another OLED structure according to an exemplary embodiment of the present disclosure.
  • FIG. 11 is a schematic diagram of the lifetime of several different guest materials and hole blocking layer materials combined structures
  • Figure 12 is a spectrum of films of different guest materials.
  • 10 anode
  • 20 hole injection layer
  • 30 hole transport layer
  • 70 electron transport layer
  • 80 electron injection layer
  • 90 cathode
  • 101 substrate
  • 102 drive circuit layer
  • 103 light emitting device
  • 104 encapsulation layer
  • 201 first insulating layer
  • 202 second insulating layer
  • 210 drive transistor
  • 211 storage capacitor
  • 301 anode
  • 302 pixel definition layer
  • 303 organic light-emitting layer
  • 304 cathode
  • 401 the first encapsulation layer
  • 402 the second encapsulation layer
  • 403 the third encapsulation layer.
  • the terms “installed”, “connected” and “connected” should be construed broadly unless otherwise expressly specified and limited. For example, it may be a fixed connection, or a detachable connection, or an integral connection; it may be a mechanical connection, or an electrical connection; it may be a direct connection, or an indirect connection through an intermediate piece, or an internal communication between two elements.
  • installed may be a fixed connection, or a detachable connection, or an integral connection; it may be a mechanical connection, or an electrical connection; it may be a direct connection, or an indirect connection through an intermediate piece, or an internal communication between two elements.
  • a transistor refers to an element including at least three terminals of a gate electrode, a drain electrode, and a source electrode.
  • the transistor has a channel region between the drain electrode (or drain electrode terminal, drain region or drain electrode) and the source electrode (or source electrode terminal, source region or source electrode), and current can flow through the drain electrode, channel region and source electrode.
  • the channel region refers to a region through which current mainly flows.
  • the first electrode may be the drain electrode and the second electrode may be the source electrode, or the first electrode may be the source electrode and the second electrode may be the drain electrode.
  • the functions of the "source electrode” and the “drain electrode” may be interchanged. Therefore, herein, “source electrode” and “drain electrode” may be interchanged with each other.
  • electrically connected includes the case where constituent elements are connected together by means of elements having some electrical function.
  • the "element having a certain electrical effect” is not particularly limited as long as it can transmit and receive electrical signals between the connected constituent elements.
  • the “element having a certain electrical effect” may be, for example, electrodes or wirings, or switching elements such as transistors, or other functional elements such as resistors, inductors, and capacitors.
  • parallel refers to a state where the angle formed by two straight lines is -10° or more and 10° or less, and therefore, also includes a state where the angle is -5° or more and 5° or less.
  • perpendicular refers to the state where the angle formed by two straight lines is 80° or more and 100° or less, and therefore includes the state where the angle is 85° or more and 95° or less.
  • film and “layer” are interchangeable.
  • conductive layer may be replaced by “conductive film” in some cases.
  • insulating film may be replaced with “insulating layer” in some cases.
  • FIG. 1 is a schematic structural diagram of an OLED display device.
  • the OLED display device may include a scan signal driver, a data signal driver, a lighting signal driver, an OLED display substrate, a first power supply unit, a second power supply unit and an initial power supply unit.
  • the OLED display substrate includes at least a plurality of scan signal lines (S1 to SN), a plurality of data signal lines (D1 to DM), and a plurality of light emission signal lines (EM1 to EMN), and the scan signal driver is configured
  • the data signal driver is configured to supply the data signals to the plurality of data signal lines (D1 to DM)
  • the light emission signal driver is configured to sequentially supply the plurality of light emission signals Lines (EM1 to EMN) provide lighting control signals.
  • the plurality of scan signal lines and the plurality of light emitting signal lines extend in the horizontal direction
  • the plurality of data signal lines extend in the vertical direction.
  • the display device includes a plurality of sub-pixels, one sub-pixel includes a pixel driving circuit and a light-emitting device, the pixel driving circuit is connected with the scanning signal line, the light-emitting control line and the data signal line, and the pixel driving circuit is configured to connect the scanning signal line and the light-emitting signal line.
  • the data voltage transmitted by the data signal line is received, and corresponding current is output to the light-emitting device, the light-emitting device is connected to the pixel driving circuit, and the light-emitting device is configured to emit light of corresponding brightness in response to the current output by the pixel driving circuit.
  • the first power supply unit, the second power supply unit and the initial power supply unit are respectively configured to supply the first power supply voltage, the second power supply voltage and the initial power supply voltage to the pixel driving circuit through the first power supply line, the second power supply line and the initial signal line.
  • FIG. 2 is a schematic plan view of a display substrate.
  • the display area may include a plurality of pixel units P arranged in a matrix, and at least one of the plurality of pixel units P includes a first sub-pixel P1 that emits light of a first color, and a sub-pixel P1 that emits light of a second color.
  • the second sub-pixel P2 and the third sub-pixel P3 emitting light of the third color, the first sub-pixel P1, the second sub-pixel P2 and the third sub-pixel P3 all include a pixel driving circuit and a light-emitting device.
  • the pixel unit P may include red (R) sub-pixels, green (G) sub-pixels, and blue (B) sub-pixels, or may include red sub-pixels, green sub-pixels, blue sub-pixels, and
  • the white (W) sub-pixel is not limited in this disclosure.
  • the shape of the sub-pixels in the pixel unit may be rectangular, diamond, pentagon or hexagonal.
  • the pixel unit includes three sub-pixels, the three sub-pixels can be arranged horizontally, vertically, or in a zigzag manner.
  • the pixel unit includes four sub-pixels, the four sub-pixels can be arranged in a horizontal, vertical, or square manner. The arrangement is not limited in this disclosure.
  • the pixel driving circuit may be a 3T1C, 4T1C, 5T1C, 5T2C, 6T1C or 7T1C structure.
  • FIG. 3 is an equivalent circuit diagram of a pixel driving circuit.
  • the pixel driving circuit may include 7 switching transistors (the first transistor T1 to the seventh transistor T7), 1 storage capacitor C and 8 signal lines (the data signal line DATA, the first scan signal line S1, The second scan signal line S2, the first initial signal line INIT1, the second initial signal line INIT2, the first power supply line VSS, the second power supply line VDD, and the light emitting signal line EM).
  • the first initial signal line INIT1 and the second initial signal line INIT2 may be the same signal line.
  • the control electrode of the first transistor T1 is connected to the second scan signal line S2, the first electrode of the first transistor T1 is connected to the first initial signal line INIT1, and the second electrode of the first transistor is connected to the second scan signal line S2.
  • Node N2 is connected.
  • the control electrode of the second transistor T2 is connected to the first scan signal line S1, the first electrode of the second transistor T2 is connected to the second node N2, and the second electrode of the second transistor T2 is connected to the third node N3.
  • the control electrode of the third transistor T3 is connected to the second node N2, the first electrode of the third transistor T3 is connected to the first node N1, and the second electrode of the third transistor T3 is connected to the third node N3.
  • the control electrode of the fourth transistor T4 is connected to the first scan signal line S1, the first electrode of the fourth transistor T4 is connected to the data signal line DATA, and the second electrode of the fourth transistor T4 is connected to the first node N1.
  • the control electrode of the fifth transistor T5 is connected to the light-emitting signal line EM, the first electrode of the fifth transistor T5 is connected to the second power supply line VDD, and the second electrode of the fifth transistor T5 is connected to the first node N1.
  • the control electrode of the sixth transistor T6 is connected to the light emitting signal line EM, the first electrode of the sixth transistor T6 is connected to the third node N3, and the second electrode of the sixth transistor T6 is connected to the first electrode of the light emitting device.
  • the control electrode of the seventh transistor T7 is connected to the first scan signal line S1, the first electrode of the seventh transistor T7 is connected to the second initial signal line INIT2, and the second electrode of the seventh transistor T7 is connected to the first electrode of the light emitting device.
  • the first end of the storage capacitor C is connected to the second power line VDD, and the second end of the storage capacitor C is connected to the second node N2.
  • the first to seventh transistors T1 to T7 may be P-type transistors, or may be N-type transistors. Using the same type of transistors in the pixel driving circuit can simplify the process flow, reduce the process difficulty of the display panel, and improve the product yield. In some possible implementations, the first to seventh transistors T1 to T7 may include P-type transistors and N-type transistors.
  • the second pole of the light emitting device is connected to the first power supply line VSS, the signal of the first power supply line VSS is a low-level signal, and the signal of the second power supply line VDD is a continuous high-level signal.
  • the first scan signal line S1 is the scan signal line in the pixel driving circuit of the display row
  • the second scan signal line S2 is the scan signal line in the pixel driving circuit of the previous display row, that is, for the nth display row, the first scan signal
  • the line S1 is S(n)
  • the second scanning signal line S2 is S(n-1)
  • the second scanning signal line S2 of this display line is the same as the first scanning signal line S1 in the pixel driving circuit of the previous display line
  • the signal lines can reduce the signal lines of the display panel and realize the narrow frame of the display panel.
  • FIG. 4 is a schematic cross-sectional structure diagram of a display substrate, illustrating the structure of three sub-pixels of the OLED display substrate.
  • the display substrate may include a driving circuit layer 102 disposed on a substrate 101 , a light emitting device 103 disposed on the side of the driving circuit layer 102 away from the substrate 101 , and a light emitting device 103 disposed on the side of the substrate 101 .
  • the encapsulation layer 104 on the side of the device 103 away from the substrate 101 .
  • the display substrate may include other film layers, such as spacer columns, etc., which are not limited in the present disclosure.
  • the substrate may be a flexible substrate, or it may be a rigid substrate.
  • the flexible substrate may include a stacked first flexible material layer, a first inorganic material layer, a semiconductor layer, a second flexible material layer and a second inorganic material layer, and the materials of the first flexible material layer and the second flexible material layer may be made of polymer.
  • the materials of the first inorganic material layer and the second inorganic material layer can be silicon nitride (SiNx ) or silicon oxide (SiOx), etc., to improve the water and oxygen resistance of the substrate, and the material of the semiconductor layer can be amorphous silicon (a-si).
  • PI imide
  • PET polyethylene terephthalate
  • surface-treated soft polymer film the materials of the first inorganic material layer and the second inorganic material layer can be silicon nitride (SiNx ) or silicon oxide (SiOx), etc., to improve the water and oxygen resistance of the substrate, and the material of the semiconductor layer can be amorphous silicon (a-si).
  • the driving circuit layer 102 of each sub-pixel may include a plurality of transistors and storage capacitors constituting the pixel driving circuit, and FIG. 3 takes the example of including one driving transistor and one storage capacitor in each sub-pixel for illustration.
  • the driving circuit layer 102 of each sub-pixel may include: a first insulating layer 201 disposed on the substrate; an active layer disposed on the first insulating layer; a second insulating layer covering the active layer layer 202; the gate electrode and the first capacitor electrode disposed on the second insulating layer 202; the third insulating layer 203 covering the gate electrode and the first capacitor electrode; the second capacitor electrode disposed on the third insulating layer 203; covering
  • the fourth insulating layer 204 of the second capacitor electrode, the second insulating layer 202, the third insulating layer 203 and the fourth insulating layer 204 are provided with via holes, and the via holes expose the active layer; they are arranged on the fourth insulating layer 204
  • the source electrode and the drain electrode are provided with via holes
  • the light emitting device 103 may include an anode 301 , a pixel definition layer 302 , an organic light emitting layer 303 and a cathode 304 .
  • the anode 301 is arranged on the flat layer 205 and is connected to the drain electrode of the driving transistor 210 through a via hole opened on the flat layer 205;
  • the pixel definition layer 302 is arranged on the anode 301 and the flat layer 205, and a pixel opening is arranged on the pixel definition layer 302 , the pixel opening exposes the anode 301;
  • the organic light-emitting layer 303 is at least partially disposed in the pixel opening, and the organic light-emitting layer 303 is connected to the anode 301;
  • the cathode 304 is disposed on the organic light-emitting layer 303, and the cathode 304 is connected to the organic light-emitting layer 303;
  • the layer 303 is driven by the anode 301 and
  • the encapsulation layer 104 may include a stacked first encapsulation layer 401, a second encapsulation layer 402 and a third encapsulation layer 403.
  • the first encapsulation layer 401 and the third encapsulation layer 403 may be made of inorganic materials.
  • the second encapsulation layer 402 can be made of organic materials, and the second encapsulation layer 402 is disposed between the first encapsulation layer 401 and the third encapsulation layer 403 to ensure that the outside water vapor cannot enter the light emitting device 103 .
  • the organic light-emitting layer of the OLED light-emitting element may include an emission layer (Emitting Layer, referred to as EML), and a hole injection layer (Hole Injection Layer, referred to as HIL), a hole transport layer (Hole Transport Layer, HTL for short), Hole Block Layer (HBL), Electron Block Layer (EBL), Electron Injection Layer (EIL), Electron Transport Layer (EIL) one or more film layers in ETL).
  • EML emission layer
  • HIL hole injection layer
  • HTL hole transport layer
  • HBL Hole Block Layer
  • EBL Electron Block Layer
  • EIL Electron Injection Layer
  • EIL Electron Transport Layer
  • the light-emitting layers of OLED light-emitting elements of different colors are different.
  • a red light-emitting element includes a red light-emitting layer
  • a green light-emitting element includes a green light-emitting layer
  • a blue light-emitting element includes a blue light-emitting layer.
  • the hole injection layer and the hole transport layer on one side of the light emitting layer can use a common layer
  • the electron injection layer and the electron transport layer on the other side of the light emitting layer can use a common layer.
  • any one or more of the hole injection layer, hole transport layer, electron injection layer, and electron transport layer may be fabricated by one process (one evaporation process or one inkjet printing process), However, isolation is achieved by the surface step difference of the formed film layer or by means of surface treatment.
  • any one or more of the hole injection layer, hole transport layer, electron injection layer and electron transport layer corresponding to adjacent sub-pixels may be isolated.
  • the organic light-emitting layer may be formed by using a fine metal mask (FMM, Fine Metal Mask) or an open mask (Open Mask) evaporation deposition, or by using an inkjet process.
  • FMM fine metal mask
  • Open Mask Open Mask
  • the blue light-emitting element has a short service life, which leads to a shift in the white balance color after long-term use, and visually appears powdered color when the white screen is turned on, which restricts the application of OLED display and cannot be applied to use.
  • Equipment with a longer life Although the study of new blue light-emitting layer materials can improve the service life of blue light-emitting elements, after years of development, improving the service life from the material direction not only costs more and more, but also has less and less potential for improvement.
  • OLED light-emitting elements depends on the performance of the material itself and the structure of the device.
  • the performance of the material itself involves functional material energy level, mobility, material stability, material fluorescence quantum yield (PLQY), etc.
  • the device collocation structure involves the energy level matching, exciton distribution, electron and hole injection of adjacent film layers , electron and hole accumulation, etc.
  • materials that are more susceptible to degradation in OLED light-emitting elements include electron blocking layers (also referred to as hole assisting layers).
  • FIG. 5 is a schematic diagram of the distribution of excitons in a light-emitting layer. As shown in Fig. 5, since the excitons of the light-emitting layer are mainly concentrated at 0% of the interface between the electron blocking layer and the light-emitting layer, excessive electrons are accumulated at the interface.
  • the electron blocking layer material itself is generally an electron-rich system (containing an aromatic amine structure) material.
  • FIG. 6 is a schematic diagram of an OLED structure according to an exemplary embodiment of the present disclosure.
  • the OLED includes an anode 10 , a cathode 90 and an organic light-emitting layer disposed between the anode 10 and the cathode 90 .
  • the organic light emitting layer may include a stacked hole transport layer 30 , an electron blocking layer 40 , a light emitting layer 50 and a hole blocking layer 60 disposed on the anode 10 Between the light-emitting layer 50 , the hole blocking layer 60 is provided between the light-emitting layer 50 and the cathode 90 .
  • the hole transport layer 30 is arranged on the side close to the anode 10, and the electron blocking layer 40 is arranged on the side close to the light emitting layer 50, that is, the hole transport layer 30 is arranged between the anode 10 and the electron blocking layer 40, and the electron blocking layer 40 is arranged between the anode 10 and the electron blocking layer 40. It is provided between the hole transport layer 30 and the light emitting layer 50 .
  • hole transport layer 30 is configured to achieve controlled migration of injected hole orientation order
  • electron blocking layer 40 is configured to form a migration barrier for electrons, preventing electrons from migrating out of light emitting layer 50 .
  • the light-emitting layer 50 is configured to recombine electrons and holes to emit light.
  • the hole blocking layer 60 is configured to form a migration barrier for holes, preventing the holes from migrating out of the light emitting layer 50 .
  • the light emitting layer 50 includes a host (Host) material and a guest (Dopant) material doped in the host material.
  • FIG. 7 is a schematic diagram of an energy level relationship of an OLED structure according to an exemplary embodiment of the present disclosure.
  • the highest occupied molecular orbital (Highest Occupied Molecular Orbit, HOMO for short) energy level HOMO Dopant of the light-emitting layer guest material is higher than the HOMO energy level HOMO EBL of the electron blocking layer EBL, and the hole
  • the HOMO energy level HOMO HTL of the transport layer HTL is higher than the HOMO energy level HOMO EBL of the electron blocking layer EBL
  • the HOMO energy level HOMO EBL of the electron blocking layer EBL is higher than the HOMO energy level HOMO Host of the host material of the light emitting layer.
  • the HOMO energy level HOMO Host is higher than the HOMO energy level HOMO HBL of the hole blocking layer HBL .
  • the lowest unoccupied molecular orbital (Lowest Unoccupied Molecular Orbital, LUMO) LUMO HBL of the hole blocking layer HBL is higher than the LUMO energy level LUMO Dopant of the light-emitting layer guest material, and the LUMO energy level LUMO Dopant of the light-emitting layer guest material is higher than the light-emitting layer host.
  • the LUMO energy level LUMO EBL of the electron blocking layer EBL is higher than the LUMO energy level LUMO HBL of the hole blocking layer HBL .
  • the lowest triplet energy T1 HBL of the hole blocking layer HBL is greater than the lowest triplet energy T1 Dopant of the light-emitting layer guest material, and the lowest triplet energy T1 Dopant of the light-emitting layer guest material is greater than the lowest triplet energy T1 Dopant of the light-emitting layer host material The triplet energy T1 Host .
  • the light-emitting layer host material and the light-emitting layer guest material may satisfy:
  • the light-emitting layer host material and the hole blocking layer may satisfy:
  • the blocking of holes is facilitated by setting the relationship of the HOMO energy level between the hole blocking layer and the host material of the light emitting layer.
  • the light emitting layer guest material and the hole blocking layer may satisfy:
  • the hole blocking layer and the light emitting layer host material may satisfy:
  • the transport of electrons is facilitated by setting the relationship of the LUMO energy level between the hole blocking layer and the host material of the light emitting layer.
  • the light emitting layer guest material and the hole blocking layer may satisfy:
  • T1 HBL is the lowest triplet energy of the hole blocking layer
  • T1 Dopant is the lowest triplet energy of the guest material of the light-emitting layer.
  • the recombination of excitons in the light-emitting layer is facilitated.
  • the hole transport layer and the electron blocking layer may satisfy:
  • the light-emitting layer host material and the hole blocking layer may satisfy:
  • E HBL is the electron mobility (Electron Mobility) of the hole blocking layer
  • E host is the electron mobility of the host material of the light-emitting layer.
  • the electron mobility relationship between the hole blocking layer and the host material of the light-emitting layer it is beneficial to increase the probability of electrons in the host material of the light-emitting layer moving towards the hole blocking layer, and is beneficial to reduce the electrons It accumulates at the interface between the light-emitting layer and the electron blocking layer, slows down the deterioration of the material of the electron blocking layer at the interface, and moves the exciton recombination region to the center of the light-emitting layer.
  • the hole transport layer and the electron blocking layer may satisfy:
  • EK HTL is the hole mobility of the hole transport layer
  • EK EBL is the hole mobility of the electron blocking layer
  • the hole mobility relationship between the hole transport layer and the electron blocking layer it is beneficial to reduce the accumulation of holes at the interface between the electron blocking layer and the light emitting layer, and slow down the electrons at the interface.
  • the material of the barrier layer deteriorates, so that the exciton recombination region moves toward the center of the light-emitting layer.
  • the energy level matching, mobility matching, or energy level and mobility matching between the hole transport layer, the electron blocking layer, the light emitting layer host material, the light emitting layer guest material and the hole blocking layer there are It is beneficial to the effective transfer of energy, reduces the accumulation of carriers at the interface, improves the stability of the interface and the material, reduces the deterioration of the material and the decrease in lifespan caused by electron accumulation, and at the same time facilitates the transport of carriers to the light-emitting layer.
  • the carrier density inside the light-emitting layer is improved, and the balance of carriers in the light-emitting layer is improved, which is conducive to the recombination of excitons in the light-emitting layer, so that the exciton recombination area moves to the center of the light-emitting layer, and the efficiency and service life are improved.
  • the HOMO Host may be about -5.70eV to -6.10eV
  • the HOMO Dopant may be about -5.25eV to -5.50eV
  • the HOMO HBL may be about -6.10eV to -6.40eV
  • the LUMO Host may be about To be -2.70eV to -3.10eV
  • LUMO Dopant can be about -2.60eV to -2.80eV
  • LUMO HBL can be about -2.55eV to -2.80eV.
  • the hole mobility EK HTL of the hole transport layer may be about 10 ⁇ 4 cm 2 /Vs to 10 ⁇ 5 cm 2 /Vs, and the hole mobility EK EBL of the electron blocking layer may be about 10 -5 cm 2 /Vs to 10 -7 cm 2 /Vs.
  • the electron mobility E HBL of the hole blocking layer may be about 10 -5 cm 2 /Vs to 10 -8 cm 2 /Vs
  • the electron mobility E host of the host material of the light emitting layer may be about 10 -6 cm 2 /Vs to 10 -8 cm 2 /Vs.
  • the HOMO Host may be about -5.75eV to -6.05eV
  • the HOMO Dopant may be about -5.3eV to -5.45eV
  • the HOMO HBL may be about -6.15eV to -6.35eV
  • the LUMO Host may be about To be -2.75eV to -3.05eV
  • LUMO Dopant can be about -2.65eV to -2.75eV
  • LUMO HBL can be about -2.60eV to -2.75eV.
  • the HOMO level and LUMO level can be measured using photoelectron spectrophotometer (AC3/AC2) or ultraviolet (UV) spectroscopy, and the mobility can be measured using space charge limited current method (SCLC).
  • the thickness of the light emitting layer 50 may be about 10 nm to 60 nm.
  • the thickness of the hole blocking layer 60 may be about 0.1 nm to 20 nm.
  • the thickness of the electron blocking layer 40 may be about 5 nm to 70 nm.
  • the thickness of the hole transport layer 30 may be about 80 nm to 120 nm.
  • the thicknesses of the light emitting layer 50 and the hole blocking layer 60 are different.
  • the thickness of the light emitting layer 50 may be greater than the thickness of the hole blocking layer 60 .
  • the thicknesses of the light emitting layer 50 and the electron blocking layer 40 are different.
  • the thickness of the light emitting layer 50 may be greater than that of the electron blocking layer 40 .
  • the thickness of the light emitting layer 50 may be about 15 nm to 30 nm
  • the thickness of the hole blocking layer 60 may be about 5 nm to 15 nm
  • the thickness of the electron blocking layer 40 may be about 5 nm to 15 nm.
  • the light-emitting layer includes a host material and a guest material doped in the host material, and the doping ratio of the guest material in the light-emitting layer is 1% to 20%.
  • the host material of the light-emitting layer can effectively transfer exciton energy to the guest material of the light-emitting layer to excite the guest material of the light-emitting layer to emit light; ”, which effectively improves the fluorescence quenching caused by the collision between the molecules of the light-emitting layer and the guest materials and the collision between the energies, and improves the luminous efficiency and device life.
  • the doping ratio refers to the ratio of the mass of the guest material to the mass of the light-emitting layer, that is, the mass percentage.
  • the host material and the guest material can be co-evaporated through a multi-source evaporation process, so that the host material and the guest material are uniformly dispersed in the light-emitting layer, and the evaporation rate of the guest material can be controlled during the evaporation process. to control the doping ratio, or to control the doping ratio by controlling the evaporation rate ratio of the host material and the guest material.
  • the light emitting layer is a blue light emitting layer.
  • the overall performance of the organic electroluminescent device can be better improved.
  • the exciton recombination area is mainly concentrated at the interface between the light-emitting layer and the electron blocking layer, so that too many electrons accumulate at the interface. Since the accumulated electrons will cause the material of the electron blocking layer to crack, thus reducing the stability and longevity of the material.
  • Exemplary embodiments of the present disclosure can increase the direction of electrons in the host material of the light emitting layer to the hole blocking layer by setting the energy level relationship and the electron mobility relationship among the host material of the light emitting layer, the guest material of the light emitting layer, and the material of the hole blocking layer.
  • the probability of moving, effectively reducing the accumulation of electrons at the interface between the light-emitting layer and the electron blocking layer not only improves the material stability of the electron blocking layer, reduces the material deterioration and performance degradation caused by electron accumulation, and improves the life.
  • the excitons are effectively recombined in the light-emitting layer to emit light, and the exciton recombination region moves to the center of the light-emitting layer, thereby improving the light-emitting efficiency.
  • the light-emitting layer host material may include anthracene derivatives (including tritium-substituted compounds), 9,10-(2-naphthyl)anthracene (AND), or 2-methyl-9,10-(2- Naphthyl ) anthracene ( MAND ), etc., have the characteristics of high fluorescence quantum yield, easy modification of molecular structure and high thermal stability. 10 -8 cm 2 /Vs.
  • the host material of the light-emitting layer may include, but is not limited to, compounds having the structures shown in Formula 1-1 to Formula 1-3:
  • the light-emitting layer guest material may include, but is not limited to, a compound having the structure shown in Formula 2:
  • X is oxygen (O) or sulfur (S);
  • Y is N-R7, B (boron), P (phosphorus);
  • R1 to R3 are hydrogen, deuterium, fluorine, C1-C4 alkyl, C3-C10 cycloalkyl, C1-C30 alkylsilyl, or C6-C10 arylsilyl;
  • R4, R5 are hydrogen, deuterium, fluorine, C1-C4 alkyl, C3-C10 cycloalkyl , C1-C30 alkylsilyl, or C6-C30 arylsilyl, substituted or unsubstituted C6-C30 aryl or heteroaryl;
  • Ar 1 , Ar 2 are substituted or unsubstituted C6 -C30 aryl or heteroaryl;
  • R1 to R3 may be the same, or may be different.
  • the compound of the structure shown in formula 2 is fused through the core (Core), and Y and N (nitrogen) are connected to the aryl or heteroaryl group, which inhibits the twist of the single bond, increases the molecular rigidity, increases the rigidity of the material, and reduces the The non-radiative transition is achieved, and the structural changes of the ground state and the excited state are small, and the Stokes shift is relatively small.
  • the lifetime and color purity (narrowing the spectrum) are improved due to the small structural changes in the ground and excited states, and the rigid planar framework is beneficial for quantum yield and efficiency.
  • the heat resistance and decomposition resistance of the material can be improved.
  • the light-emitting layer guest material may include, but is not limited to, compounds having the structures shown in Formula 2-1 to Formula 2-9:
  • the material of the hole blocking layer may include, but is not limited to, a compound having the structure shown in Formula 3-1:
  • R1, R2 are hydrogen, deuterium, fluorine, C1-C4 alkyl, C3-C10 cycloalkyl, C1-C30 alkylsilyl, or C6-C10 arylsilyl;
  • Ar 1 , Ar 2 is a substituted or unsubstituted C6-C30 aryl or heteroaryl group, one of which is a heteroaryl group containing at least one nitrogen;
  • R1 and R2 may be the same or different; Ar 1 and Ar 2 are different.
  • the material of the hole blocking layer may include, but is not limited to, a compound having the structure shown in Formula 3-2:
  • L is a substituted or unsubstituted C6-C30 aryl or heteroaryl
  • A is a substituted or unsubstituted nitrogen-containing aromatic heterocycle, containing at least one nitrogen atom
  • R1, R2 are methyl, aryl
  • R1, R2 may be the same, or may be different.
  • the hole blocking layer material may include, but is not limited to, compounds having the structures shown in Formula 3-3 to Formula 3-14:
  • the material of the electron blocking layer may include, but is not limited to, a compound having the structure shown in Formula 4-1 or Formula 4-2:
  • L1-L3 are single bonds, C6-C15 aryl; Ar 1 , Ar 2 are substituted or unsubstituted C6-C40 aryl, arylamine or fluorenyl, Ar 1 and Ar 2 are different groups , one of which can also be a substituent represented by formula 5.
  • R1-R5 are hydrogen, deuterium, alkyl, cycloalkyl or C6-C36 aryl.
  • one of Ar 1 and Ar 2 may also be a substituent as represented by Formulas 5-1 to 5-7.
  • the compounds of the structures shown in Formula 4-1 and Formula 4-2 are asymmetric structures, which can improve the thermal stability of the material, inhibit crystallization, and improve the film stability.
  • the hole mobility of the electron blocking layer may be about 10 -5 cm 2 /Vs to 10 -7 cm 2 /Vs.
  • the material of the electron blocking layer may include, but is not limited to, compounds having the structures shown in Formula 4-1-1 to Formula 4-1-6:
  • the material of the electron blocking layer may include, but is not limited to, compounds having the structures shown in Formula 4-2-1 to Formula 4-2-6:
  • FIG. 8 is the electrochemical stability test result of an electron blocking layer material according to an exemplary embodiment of the present disclosure
  • FIG. 9 is the electrochemical stability test result of another electron blocking layer material according to an exemplary embodiment of the present disclosure.
  • the electrochemical stability The test method is cyclic voltammetry (Cyclic Voltammetry).
  • Cyclic Voltammetry Cyclic Voltammetry
  • the electron blocking layer adopts the compound having the structure shown in formula 4-1-1, and the material has good electrochemical stability.
  • the electron blocking layer adopts the compound having the structure shown in formula 4-1-4, and the material has good electrochemical stability.
  • the materials of the electron blocking layer, the host material of the light-emitting layer, the guest material of the light-emitting layer and the hole blocking layer may be other materials known to those skilled in the art that satisfy the above energy level relationship and mobility relationship. The disclosure is not limited here.
  • FIG. 10 is a schematic diagram of another OLED structure according to an exemplary embodiment of the present disclosure.
  • the OLED includes an anode 10 , a cathode 90 and an organic light-emitting layer disposed between the anode 10 and the cathode 90 .
  • the organic light emitting layer may include a stacked hole injection layer 20 , a hole transport layer 30 , an electron blocking layer 40 , a light emitting layer 50 , a hole blocking layer 60 , an electron transport layer 70 and an electron injection layer 80.
  • the hole injection layer 20, the hole transport layer 30 and the electron blocking layer 40 are arranged between the anode 10 and the light emitting layer 50, the hole injection layer 20 is connected to the anode 10, the electron blocking layer 40 is connected to the light emitting layer 50, and the hole transports Layer 30 is disposed between hole injection layer 20 and electron blocking layer 40 .
  • the hole blocking layer 60, the electron transport layer 70 and the electron injection layer 80 are arranged between the light emitting layer 50 and the cathode 90, the hole blocking layer 60 is connected with the light emitting layer 50, the electron injection layer 80 is connected with the cathode 90, and the electron transport layer 70 It is provided between the hole blocking layer 60 and the electron injection layer 80 .
  • the hole injection layer 20 is configured to lower a barrier for hole injection from the anode, enabling efficient injection of holes from the anode into the light emitting layer 50 .
  • the hole transport layer 30 is configured to achieve controlled migration of the directional order of the injected holes.
  • the electron blocking layer 40 is configured to form a migration barrier for electrons, preventing electrons from migrating out of the light emitting layer 50 .
  • the light-emitting layer 50 is configured to recombine electrons and holes to emit light.
  • the hole blocking layer 60 is configured to form a migration barrier for holes, preventing the holes from migrating out of the light emitting layer 50 .
  • Electron transport layer 70 is configured to achieve controlled migration of the directional order of injected electrons.
  • the electron injection layer 80 is configured to lower a barrier for injecting electrons from the cathode, so that electrons can be efficiently injected from the cathode to the light-emitting layer 50 .
  • the structures and materials of the light emitting layer 50 and the hole blocking layer 60 are the same as or similar to those of the foregoing embodiments, and will not be repeated here.
  • the anode may employ a material with a high work function.
  • the anode can be made of a transparent oxide material, such as indium tin oxide (ITO) or indium zinc oxide (IZO), and the thickness of the anode can be about 80 nm to 200 nm.
  • the anode can use a composite structure of metal and transparent oxide, such as Ag/ITO, Ag/IZO or ITO/Ag/ITO, etc.
  • the thickness of the metal layer in the anode can be about 80nm to 100nm, and the transparent oxide in the anode can be used.
  • the thickness of the material can be about 5 nm to 20 nm, so that the average reflectivity of the anode in the visible light region is about 85% to 95%.
  • the cathode may be made of a metal material, which may be formed by an evaporation process, and the metal material may be magnesium (Mg), silver (Ag), or aluminum (Al), or an alloy material such as
  • Mg magnesium
  • Al aluminum
  • the ratio of Mg:Ag is about 9:1 to 1:9
  • the thickness of the cathode can be about 10nm to 20nm, so that the average transmittance of the cathode at a wavelength of 530nm is about 50% to 60%.
  • the cathode can be magnesium (Mg), silver (Ag), aluminum (Al) or Mg:Ag alloy, and the thickness of the cathode can be greater than about 80 nm, so that the cathode has good reflectivity.
  • the hole injection layer may employ inorganic oxides such as molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide , tantalum oxide, silver oxide, tungsten oxide, or manganese oxide, or p-type dopants and dopants of hole transport materials such as hexacyanohexaazatriphenylene can be employed , 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinodimethane (F4-TCNQ) dimethyl or 1,2,3-tri[(cyano) (4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane, etc.
  • inorganic oxides such as molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide , tanta
  • the thickness of the hole injection layer may be about 5 nm to 20 nm.
  • the hole transport layer may use a material with high hole mobility, such as an aromatic amine compound with hole transport properties, whose substituent groups may be carbazole, methylfluorene, spirofluorene, Dibenzothiophene or furan, etc., such as 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB), N,N'-bis(3-methylphenyl) )-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4-phenyl-4'-(9-phenylfluoren-9-yl ) triphenylamine (BAFLP), 4,4'-bis[N-(9,9-dimethylfluoren-2-yl)-N-phenylamino]biphenyl (DFLDPBi), 4,4'- Bis(9-carbazolyl)biphen
  • NNB 4,
  • the thickness of the hole transport layer may be about 80 nm to 120 nm, and the conductivity of the hole transport layer is less than or equal to that of the hole injection layer.
  • the electron blocking layer can be an aromatic amine compound with hole transport properties, and its substituent can be carbazole, methyl fluorene, spirofluorene, dibenzothiophene or furan, etc., such as 4, 4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB), N,N'-bis(3-methylphenyl)-N,N'-diphenyl- [1,1'-biphenyl]-4,4'-diamine (TPD), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (BAFLP), 4, 4'-bis[N-(9,9-dimethylfluoren-2-yl)-N-phenylamino]biphenyl (DFLDPBi), 4,4'-bis(9-carbazolyl)biphenyl ( CBP) or 9-phenyl-3-
  • NPB N
  • the thickness of the electron blocking layer may be about 5 nm to 70 nm.
  • the conductivity of the electron blocking layer is less than or equal to the conductivity of the hole injection layer.
  • the electron transport layer may employ an aromatic heterocyclic compound, such as benzimidazole derivatives, imidazopyridine derivatives, benzimidazophenanthridine derivatives and other imidazole derivatives; pyrimidine derivatives, triazine derivatives, etc. Derivatives and other azine derivatives; quinoline derivatives, isoquinoline derivatives, phenanthroline derivatives, etc., compounds containing a nitrogen-containing six-membered ring structure (including compounds having a phosphine oxide-based substituent on a heterocycle) Wait.
  • an aromatic heterocyclic compound such as benzimidazole derivatives, imidazopyridine derivatives, benzimidazophenanthridine derivatives and other imidazole derivatives; pyrimidine derivatives, triazine derivatives, etc. Derivatives and other azine derivatives; quinoline derivatives, isoquinoline derivatives, phenanthroline derivatives, etc., compounds containing a nitrogen-
  • the thickness of the electron transport layer may be about 20 nm to 50 nm.
  • the electron injection layer may adopt alkali metals or metals, such as materials such as lithium fluoride (LiF), ytterbium (Yb), magnesium (Mg), or calcium (Ca), or compounds of these alkali metals or metals Wait.
  • alkali metals or metals such as materials such as lithium fluoride (LiF), ytterbium (Yb), magnesium (Mg), or calcium (Ca), or compounds of these alkali metals or metals Wait.
  • the electron injection layer may have a thickness of about 0.5 nm to 5 nm.
  • the OLED may include an encapsulation layer, and the encapsulation layer may be encapsulated with a cover plate, or may be encapsulated with a thin film.
  • the thickness of the organic light-emitting layer between the cathode and the anode can be designed to meet the optical path requirements of the optical micro-resonator, so as to obtain optimal light intensity and color.
  • the display substrate including the OLED structure may be prepared by the following preparation method.
  • a driving circuit layer is formed on a substrate through a patterning process, and the driving circuit layer of each sub-pixel may include a driving transistor and a storage capacitor constituting a pixel driving circuit.
  • a flat layer is formed on the substrate on which the aforementioned structure is formed, and a via hole exposing the drain electrode of the driving transistor is formed on the flat layer of each sub-pixel.
  • an anode is formed through a patterning process, and the anode of each sub-pixel is connected to the drain electrode of the driving transistor through a via hole on the flat layer.
  • a pixel definition layer is formed through a patterning process, and a pixel opening exposing the anode is formed on the pixel definition layer of each sub-pixel, and each pixel opening serves as a light-emitting area of each sub-pixel.
  • the hole injection layer and the hole transport layer are sequentially evaporated using an open mask, and a common layer of the hole injection layer and the hole transport layer is formed on the display substrate, that is, all The hole injection layers of the sub-pixels are connected, and the hole transport layers of all the sub-pixels are connected.
  • the thickness of the hole injection layer may be about 5 nm to 20 nm, and the thickness of the hole transport layer may be about 80 nm to 120 nm.
  • the area of each of the hole injection layer and the hole transport layer is approximately the same, and the thicknesses thereof are different.
  • the electron blocking layer and the red light-emitting layer, the electron blocking layer and the green light-emitting layer, and the electron blocking layer and the blue light-emitting layer were respectively evaporated on different sub-pixels using a fine metal mask.
  • the light-emitting layers may have a small amount of overlap (eg, the overlapping portion occupies less than 10% of the area of the respective light-emitting layer patterns), or may be isolated.
  • the thickness of the electron blocking layer may be about 5 nm to 70 nm, and the thickness of the light emitting layer may be about 10 nm to 60 nm.
  • the hole blocking layer, the electron transport layer, the electron injection layer and the cathode are sequentially evaporated using an open mask to form a common layer of the hole blocking layer, the electron transport layer, the electron injection layer and the cathode on the display substrate, namely The hole blocking layers of all sub-pixels are connected, the electron transport layers of all sub-pixels are connected, the electron injection layers of all sub-pixels are connected, and the cathodes of all sub-pixels are connected.
  • the thickness of the hole blocking layer may be about 0.1 nm to 20 nm, and the thickness of the electron transport layer may be about 20 nm to 50 nm.
  • the blue light emitting layer includes a blue host material (BH) and a blue guest material (BD), and the doping ratio may be about 1% to 20%.
  • Evaporating the blue light-emitting layer can use a multi-source co-evaporation method to form a light-emitting layer containing a host material and a guest material.
  • the doping ratio can be regulated by controlling the evaporation rate of the guest material, or by controlling the host material.
  • the doping ratio is regulated by the evaporation rate ratio of the material and the guest material.
  • the orthographic projection of one or more of the hole injection layer, hole transport layer, hole blocking layer, electron transport layer, electron injection layer, and cathode on the substrate is continuous.
  • at least one of the hole injection layer, the hole transport layer, the hole blocking layer, the electron transport layer, the electron injection layer, and the cathode of at least one row or column of subpixels is connected.
  • at least one of the hole injection layer, the hole transport layer, the hole blocking layer, the electron transport layer, the electron injection layer, and the cathode of the plurality of subpixels is connected.
  • the organic light emitting layer may include a microcavity adjustment layer between the hole transport layer and the light emitting layer.
  • a fine metal mask can be used to vapor-deposit a red microcavity adjusting layer and a red light-emitting layer, a green microcavity adjusting layer and a green light-emitting layer, and a blue microcavity adjusting layer on different sub-pixels, respectively. layer and blue light-emitting layer.
  • the red microcavity adjusting layer, the green microcavity adjusting layer, and the blue microcavity adjusting layer may include electron blocking layers.
  • the orthographic projection of the hole blocking layer on the substrate includes the orthographic projection of the light emitting layer on the substrate, the holes The area of the blocking layer is larger than that of the light-emitting layer.
  • the orthographic projection of the hole blocking layer on the substrate at least includes the orthographic projection of the light-emitting regions of the two sub-pixels on the substrate.
  • the orthographic projection of the light-emitting layer of at least part of the sub-pixels on the substrate overlaps with the orthographic projection of the pixel driving circuit driving on the substrate.
  • Table 1 is the performance comparison result of several film layer material combination structures according to the exemplary embodiments of the present disclosure.
  • the structures of the organic light-emitting layers of the comparative structure 1 and structure 1 to structure 6 are all HIL/HTL/EBL/BEML/HBL/ETL, and the thicknesses of the corresponding film layers of the comparative structure 1, structure 1 to structure 6 are the same.
  • the materials and thicknesses of the hole injection layer HIL, the hole transport layer HTL, the electron blocking layer EBL and the electron transport layer ETL of the comparative structure 1, structures 1 to 6 are the same, and the blue light host materials of the comparative structure 1, structures 1 to 6 are compared. same.
  • the related materials of the same film layer in the comparison structure 1, structure 1 to structure 6 are:
  • the blue light emitting layers BEML of comparative structure 1 and structure 1 to structure 6 all include a blue light host material and a blue light guest material, and the doping ratio is 3%.
  • the blue light guest materials of the comparative structure 1 and structures 1 to 6 are different, and the materials of the hole blocking layers HBL of the comparative structure 1 and structures 1 to 6 are different.
  • the blue light guest material and the hole blocking layer HBL of the comparative structure 1, structure 1 to structure 6 are as follows:
  • Figure 11 is a schematic representation of lifetimes for several different guest material and hole blocking layer material combinations.
  • the structures 1 to 6 compared with the comparative structure 1, the structures 1 to 6 have obvious improvements in terms of reducing voltage, improving efficiency, and improving lifespan.
  • the lifespan of structures 1 to 6 The reduction ranges are all smaller than the reduction range of the life of Comparative Structure 1.
  • the blue light guest materials of structure 2 and structure 4 contain trimethyl silicon substitution, and the thermal stability of the material is relatively high, so the life span of structure 2 and structure 4 is increased more than that of structure 5.
  • the materials of the hole blocking layers of structure 2 and structure 4 are relatively long-lived materials.
  • the blue light guest material of structure 3 contains trimethylsilicon substitution, due to the use of different hole blocking layer materials, the The degree of increase in life is lower than that of Structures 2 and 4.
  • the mobility of the material of the hole blocking layer of Structures 2 and 6 is relatively large, so the degree of increase in efficiency of Structures 2 and 6 is greater than that of the other structures.
  • the energy level collocation of the host material, the guest material and the material of the hole blocking layer is more reasonable, so the efficiency is increased to a greater degree.
  • Exemplary embodiments of the present disclosure can increase the amount of electrons in the host material of the light emitting layer moving toward the hole blocking layer by properly matching the energy level relationship and mobility relationship of the host material of the light emitting layer, the guest material of the light emitting layer, and the material of the hole blocking layer.
  • Figure 12 is a spectrum of films of different guest materials.
  • the structure 1 material film formed by vapor deposition of the blue guest material of structure 1 is represented by a solid line
  • the contrast structure material film formed by vapor deposition of the blue guest material of comparative structure 1 is represented by a dotted line
  • the fluorescence spectrum is tested by a fluorescence spectrometer.
  • the blue light guest material proposed by the present disclosure has a narrower emission spectrum than the blue light guest material of the comparative structure, which is beneficial to the improvement of color purity.
  • Table 2 is the performance comparison results of other combination structures of film layer materials according to the exemplary embodiments of the present disclosure.
  • the structures of the organic light-emitting layers of the comparative structure 2, structure 7 to structure 10 are all HIL/HTL/EBL/BEML/HBL/ETL, and the thicknesses of the corresponding film layers of comparative structure 2, structure 7 to structure 10 are the same.
  • the materials and thicknesses of the hole injection layer HIL, the hole transport layer HTL, the hole blocking layer HBL and the electron transport layer ETL of the comparative structure 2, structure 7 to structure 10 are the same, and the blue light guests of the comparative structure 2, structure 7 to structure 10 are compared. Materials are the same.
  • the related materials of the same film layer in the comparison structure 2, structure 7 to structure 10 are:
  • the blue light emitting layers BEML of comparative structure 2, structure 7 to structure 10 all include blue light host material and blue light guest material, and the doping ratio is 5%. Comparing with structure 2, structure 7 to structure 10, the materials of the electron blocking layers EBL are different, and the blue light guest materials are different. The materials of the electron blocking layer EBL and the blue light guest material for the comparative structure 2, structure 7 to structure 10 are:
  • the structures 7 to 10 have obvious improvements in reducing the voltage, improving the efficiency, and improving the lifespan, and through the combination of different electron blocking layers and light-emitting layer guest materials, the lifespan significantly improved.
  • Exemplary embodiments of the present disclosure facilitate the efficient transfer of energy, reduce the accumulation of carriers at the interface, and improve the stability of the interface and the material by reasonably matching the energy level relationship and the mobility relationship between the electron blocking layer and the guest material of the light-emitting layer.
  • which reduces the deterioration of materials and the decrease in lifespan caused by electron accumulation, and at the same time facilitates the transport of carriers into the light-emitting layer, increases the carrier density inside the light-emitting layer, and improves the balance of carriers in the light-emitting layer.
  • the excitons recombine and emit light in the light-emitting layer, so that the exciton recombination region moves to the center of the light-emitting layer, and the efficiency and service life are improved.
  • the exemplary embodiment of the present disclosure effectively improves the crystallinity and stability of the material by optimizing the guest materials of the electron blocking layer and the light emitting layer, and combining the electron blocking layer and the guest material of the light emitting layer with high efficiency and stability, and avoids the deterioration of the material. lifetime decay, maximizing the lifetime of blue light-emitting devices.
  • the present disclosure also provides a display device including the aforementioned organic electroluminescent device.
  • the display device can be any product or component with a display function, such as a mobile phone, a tablet computer, a TV, a monitor, a notebook computer, a digital photo frame, a navigator, a car monitor, a smart watch, a smart bracelet, and the like.

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Abstract

一种有机电致发光器件和显示装置。有机电致发光器件包括阳极、阴极以及设置在所述阳极和阴极之间的发光层，所述发光层包括主体材料和掺杂在所述主体材料中的客体材料；所述主体材料和客体材料满足: │HOMODopant│<│HOMOHost│,│LUMODopant│≤│LUMOHost│; 其中，HOMODopant 为所述客体材料的最高占据分子轨道 HOMO 能级, HOMOHost 为所述主体材料的 HOMO 能级，LUMODopant 为所述客体材料最低未占分子轨道 LUMO能级, LUMOhost 为所述主体材料的 LUMO 能级。

Description

有机电致发光器件和显示装置
本申请要求于2020年10月23日提交中国受理局、申请号为PCT/CN2020/123375、发明名称为“有机电致发光器件和显示装置”的PCT国际专利申请的优先权，其内容应理解为通过引用的方式并入本申请中。
技术领域
本公开涉及但不限于显示技术领域，尤指一种有机电致发光器件和显示装置。
背景技术
有机电致发光器件(Organic Light Emitting Device，简称OLED)为主动发光器件，具有亮度高、色彩饱和、超薄、广视角、较低耗电、极高反应速度和可弯曲等优点，广泛应用于在平板显示领域。
OLED包括阳极、阴极以及设置在阳极和阴极之间的发光层，其发光原理是将空穴、电子分别由阳极、阴极注入至发光层，当电子和空穴在发光层中相遇时，电子和空穴复合从而产生激子(exciton)，在从激发态转变为基态的同时，这些激子发光。
发明内容
以下是对本文详细描述的主题的概述。本概述并非是为了限制权利要求的保护范围。
一种有机电致发光器件，包括阳极、阴极以及设置在所述阳极和阴极之间的发光层，所述发光层包括主体材料和掺杂在所述主体材料中的客体材料；所述主体材料和客体材料满足：
│HOMO Dopant│<│HOMO Host│，│LUMO Dopant│≤│LUMO Host│；
其中，HOMO Dopant为所述客体材料的最高占据分子轨道HOMO能级， HOMO Host为所述主体材料的HOMO能级，LUMO Dopant为所述客体材料最低未占分子轨道LUMO能级，LUMO host为所述主体材料的LUMO能级。
在示例性实施方式中，所述发光层和阴极之间还设置有空穴阻挡层，所述主体材料、客体材料和空穴阻挡层满足：
│HOMO HBL-HOMO Host│≥0.5eV，
其中，HOMO HBL为所述空穴阻挡层的HOMO能级。
在示例性实施方式中，所述客体材料和空穴阻挡层满足：
│HOMO HBL-HOMO Dopant│≥0.9eV。
在示例性实施方式中，所述主体材料和空穴阻挡层满足：
E HBL≥E host，
其中，E HBL为所述空穴阻挡层的电子迁移率，E host为所述主体材料的电子迁移率。
在示例性实施方式中，所述空穴阻挡层的电子迁移率E HBL为10 -5cm 2/Vs至10 -8cm 2/Vs，所述主体材料的电子迁移率E host为10 -6cm 2/Vs至10 -8cm 2/Vs。
在示例性实施方式中，所述主体材料和空穴阻挡层满足：
│LUMO host│>│LUMO HBL│
其中，LUMO HBL为所述空穴阻挡层的LUMO能级。
在示例性实施方式中，所述客体材料和空穴阻挡层的材料满足：
T1 HBL>T1 Dopant，
其中，T1 HBL为所述空穴阻挡层的最低三重态能量，T1 Dopant为所述客体材料的最低三重态能量。
在示例性实施方式中，所述阳极和发光层之间还设置有空穴传输层和电子阻挡层，所述空穴传输层和电子阻挡层满足：
│HOMO HTL-HOMO EBL│<0.3eV，
其中，HOMO HTL为所述空穴传输层的HOMO能级，HOMO EBL为所述电子阻挡层的HOMO能级。
在示例性实施方式中，所述电子阻挡层和主体材料满足：
0.2eV≤│HOMO EBL-HOMO Host│＜0.5eV。
在示例性实施方式中，所述空穴传输层和电子阻挡层满足：
EK HTL>EK EBL，
其中，EK HTL为所述空穴传输层的空穴迁移率，EK EBL为所述电子阻挡层的空穴迁移率。
在示例性实施方式中，所述空穴传输层的空穴迁移率为10 -4cm 2/Vs至10 -5cm 2/Vs，所述电子阻挡层的空穴迁移率为10 -5cm 2/Vs至10 -7cm 2/Vs。
在示例性实施方式中，所述主体材料包括蒽衍生物、9，10-(2-萘基)蒽或2-甲基-9，10-(2-萘基)蒽。
在示例性实施方式中，所述主体材料包括如下具有如下结构式的化合物的一种或多种：
Figure PCTCN2020138927-appb-000001
其中，D为氚。
在示例性实施方式中，所述客体材料包括具有如下结构式的化合物：
Figure PCTCN2020138927-appb-000002
其中，X为O或S；Y为N-R7，B，P；R1至R3为氢，氘，氟，C1-C4的烷基，C3-C10的环烷基，C1-C30的烷基甲硅烷基，或C6-C10的芳基甲硅烷基；R4、R5为氢，氘，氟，C1-C4的烷基，C3-C10的环烷基，C1-C30的烷基甲硅烷基，或C6-C30的芳基甲硅烷基，取代或未取代的C6-C30的芳基或杂芳基；Ar 1、Ar 2为取代或未取代的C6-C30的芳基或杂芳基；R1至R3相同或者不同。
在示例性实施方式中，所述客体材料包括具有如下结构式的化合物的一种或多种：
Figure PCTCN2020138927-appb-000003
Figure PCTCN2020138927-appb-000004
在示例性实施方式中，其中，所述空穴阻挡层包括但不限于具有如下式所示结构的化合物：
Figure PCTCN2020138927-appb-000005
其中，R1、R2为氢、氘、氟，C1-C4的烷基，C3-C10的环烷基，C1-C30 的烷基甲硅烷基，或者C6-C10的芳基甲硅烷基；Ar 1、Ar 2为取代或未取代的C6-C30的芳基或杂芳基，其中一个为至少含有1个氮的杂芳基；R1、R2相同或者不同；Ar 1和Ar 2不同。
在示例性实施方式中，所述空穴阻挡层包括但不限于具有如下结构式的化合物：
Figure PCTCN2020138927-appb-000006
其中，L为取代或未取代的C6-C30的芳基或杂芳基；A为取代或未取代的含氮芳杂环，至少含有1个氮原子；R1、R2为甲基，芳基；R1、R2相同或者不同。
在示例性实施方式中，所述空穴阻挡层包括具有如下结构式的化合物的一种或多种：
Figure PCTCN2020138927-appb-000007
Figure PCTCN2020138927-appb-000008
Figure PCTCN2020138927-appb-000009
Figure PCTCN2020138927-appb-000010
在示例性实施方式中，所述电子阻挡层的材料包括但不限于具有如下结构式的化合物中的任意一种：
Figure PCTCN2020138927-appb-000011
其中，L1-L3为单键，C6-C15的芳基；Ar 1、Ar 2为取代或未取代的C6-C40的芳基、芳胺基或芴基，Ar 1和Ar 2为不同基团。
在示例性实施方式中，所述电子阻挡层的材料包括具有如下结构式的化合物的一种或多种：
Figure PCTCN2020138927-appb-000012
Figure PCTCN2020138927-appb-000013
Figure PCTCN2020138927-appb-000014
Figure PCTCN2020138927-appb-000015
在示例性实施方式中，Ar 1和Ar 2中的一个为具有如下结构式表示的取代基：
Figure PCTCN2020138927-appb-000016
其中，R1-R5为氢，氘，烷基，环烷基或C6-C36的芳基。
在示例性实施方式中，Ar 1和Ar 2中的一个为具有如下结构式表示的取代基：
Figure PCTCN2020138927-appb-000017
Figure PCTCN2020138927-appb-000018
一种显示装置，包括前述的有机电致发光器件。
在阅读并理解了附图和详细描述后，可以明白其他方面。
附图说明
附图用来提供对本公开技术方案的进一步理解，并且构成说明书的一部分，与本公开的实施例一起用于解释本公开的技术方案，并不构成对本公开技术方案的限制。附图中各部件的形状和大小不反映真实比例，目的只是示意说明本公开内容。
图1为一种OLED显示装置的结构示意图；
图2为一种显示基板的平面结构示意图；
图3为一种像素驱动电路的等效电路图；
图4为一种显示基板的剖面结构示意图；
图5为一种发光层中激子分布的示意图；
图6为本公开示例性实施例一种OLED结构的示意图；
图7为本公开示例性实施例一种OLED结构的能级关系示意图；
图8为本公开示例性实施例一种电子阻挡层的电化学稳定性测试结果；
图9为本公开示例性实施例另一种电子阻挡层的电化学稳定性测试结果；
图10为本公开示例性实施例另一种OLED结构的示意图；
图11为几种不同客体材料和空穴阻挡层材料组合结构的寿命示意图；
图12为不同客体材料膜的光谱图。
附图标记说明:
10—阳极；             20—空穴注入层；       30—空穴传输层；
40—电子阻挡层；       50—发光层；           60—空穴阻挡层；
70—电子传输层；       80—电子注入层；       90—阴极；
101—基底；            102—驱动电路层；      103—发光器件。
104—封装层；          201—第一绝缘层；      202—第二绝缘层；
203—第三绝缘层；      204—第四绝缘层；      205—平坦层；
210—驱动晶体管；      211—存储电容；        301—阳极；
302—像素定义层；      303—有机发光层；      304—阴极；
401—第一封装层；      402—第二封装层；      403—第三封装层。
具体实施方式
本文中的实施方式可以以多个不同形式来实施。所属技术领域的普通技术人员可以很容易地理解一个事实，就是实现方式和内容可以在不脱离本公开的宗旨及其范围的条件下被变换为各种各样的形式。因此，本公开不应该被解释为仅限定在下面的实施方式所记载的内容中。在不冲突的情况下，本公开中的实施例及实施例中的特征可以相互任意组合。
在附图中，有时为了明确起见，可能夸大表示了构成要素的大小、层的厚度或区域。因此，本公开的任意一个实现方式并不一定限定于图中所示尺 寸，附图中部件的形状和大小不反映真实比例。此外，附图示意性地示出了理想的例子，本公开的任意一个实现方式不局限于附图所示的形状或数值等。
本文中的“第一”、“第二”、“第三”等序数词是为了避免构成要素的混同而设置，而不是为了在数量方面上进行限定的。
在本文中，为了方便起见，使用“中部”、“上”、“下”、“前”、“后”、“竖直”、“水平”、“顶”、“底”、“内”、“外”等指示方位或位置关系的词句以参照附图说明构成要素的位置关系，仅是为了便于描述实施方式和简化描述，而不是指示或暗示所指的装置或元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本公开的限制。构成要素的位置关系可根据描述的构成要素的方向进行适当地改变。因此，不局限于在文中说明的词句，根据情况可以适当地更换。
在本文中，除非另有明确的规定和限定，术语“安装”、“相连”、“连接”应做广义理解。例如，可以是固定连接，或可拆卸连接，或一体地连接；可以是机械连接，或电连接；可以是直接相连，或通过中间件间接相连，或两个元件内部的连通。对于本领域的普通技术人员而言，可以根据情况理解上述术语在本公开中的含义。
在本文中，晶体管是指至少包括栅电极、漏电极以及源电极这三个端子的元件。晶体管在漏电极(或称漏电极端子、漏区域或漏电极)与源电极(或称源电极端子、源区域或源电极)之间具有沟道区域，并且电流能够流过漏电极、沟道区域以及源电极。在本文中，沟道区域是指电流主要流过的区域。
在本文中，第一极可以为漏电极、第二极可以为源电极，或者第一极可以为源电极、第二极可以为漏电极。在使用极性相反的晶体管的情况或电路工作中的电流方向变化的情况下，“源电极”及“漏电极”的功能有时可以互相调换。因此，在本文中，“源电极”和“漏电极”可以互相调换。
在本文中，“电连接”包括构成要素通过具有某种电作用的元件连接在一起的情况。“具有某种电作用的元件”只要可以进行连接的构成要素间的电信 号的授受，就对其没有特别的限制。“具有某种电作用的元件”例如可以是电极或布线，或者是晶体管等开关元件，或者是电阻器、电感器或电容器等其它功能元件等。
在本文中，“平行”是指两条直线形成的角度为-10°以上且10°以下的状态，因此，也包括该角度为-5°以上且5°以下的状态。另外，“垂直”是指两条直线形成的角度为80°以上且100°以下的状态，因此，也包括85°以上且95°以下的角度的状态。
在本文中，“膜”和“层”可以相互调换。例如，有时可以将“导电层”换成为“导电膜”。与此同样，有时可以将“绝缘膜”换成为“绝缘层”。
本文中的“约”，是指不严格限定界限，允许工艺和测量误差范围内的数值。
图1为一种OLED显示装置的结构示意图。如图1所示，OLED显示装置可以包括扫描信号驱动器、数据信号驱动器、发光信号驱动器、OLED显示基板、第一电源单元、第二电源单元和初始电源单元。在示例性实施方式中，OLED显示基板至少包括多个扫描信号线(S1到SN)、多个数据信号线(D1到DM)和多个发光信号线(EM1到EMN)，扫描信号驱动器被配置为依次向多个扫描信号线(S1到SN)提供扫描信号，数据信号驱动器被配置为向多个数据信号线(D1到DM)提供数据信号，发光信号驱动器被配置为依次向多个发光信号线(EM1到EMN)提供发光控制信号。在示例性实施方式中，多个扫描信号线和多个发光信号线沿着水平方向延伸，多个数据信号线沿着竖直方向延伸。所述显示装置包括多个子像素，一个子像素包括像素驱动电路和发光器件，像素驱动电路与扫描信号线、发光控制线和数据信号线连接，像素驱动电路被配置为在扫描信号线和发光信号线的控制下，接收数据信号线传输的数据电压，向所述发光器件输出相应的电流，发光器件与像素驱动电路连接，发光器件被配置为响应像素驱动电路输出的电流发出相应亮度的光。第一电源单元、第二电源单元和初始电源单元分别被配置为通过第一电源线、第二电源线和初始信号线向像素驱动电路提供第一电源电压、第二电源电压和初始电源电压。
图2为一种显示基板的平面结构示意图。如图2所示，显示区域可以包 括以矩阵方式排布的多个像素单元P，多个像素单元P的至少一个中包括出射第一颜色光线的第一子像素P1、出射第二颜色光线的第二子像素P2和出射第三颜色光线的第三子像素P3，第一子像素P1、第二子像素P2和第三子像素P3均包括像素驱动电路和发光器件。在示例性实施方式中，像素单元P可以包括红色(R)子像素、绿色(G)子像素和蓝色(B)子像素，或者可以包括红色子像素、绿色子像素、蓝色子像素和白色(W)子像素，本公开在此不做限定。在示例性实施方式中，像素单元中子像素的形状可以是矩形状、菱形、五边形或六边形。像素单元包括三个子像素时，三个子像素可以采用水平并列、竖直并列或品字方式排列，像素单元包括四个子像素时，四个子像素可以采用水平并列、竖直并列或正方形(Square)方式排列，本公开在此不做限定。
在示例性实施方式中，像素驱动电路可以是3T1C、4T1C、5T1C、5T2C、6T1C或7T1C结构。图3为一种像素驱动电路的等效电路图。如图3所示，像素驱动电路可以包括7个开关晶体管(第一晶体管T1到第七晶体管T7)、1个存储电容C和8个信号线(数据信号线DATA、第一扫描信号线S1、第二扫描信号线S2、第一初始信号线INIT1、第二初始信号线INIT2、第一电源线VSS、第二电源线VDD和发光信号线EM)。其中，第一初始信号线INIT1、第二初始信号线INIT2可以为同一条信号线。
在示例性实施方式中，第一晶体管T1的控制极与第二扫描信号线S2连接，第一晶体管T1的第一极与第一初始信号线INIT1连接，第一晶体管的第二极与第二节点N2连接。第二晶体管T2的控制极与第一扫描信号线S1连接，第二晶体管T2的第一极与第二节点N2连接，第二晶体管T2的第二极与第三节点N3连接。第三晶体管T3的控制极与第二节点N2连接，第三晶体管T3的第一极与第一节点N1连接，第三晶体管T3的第二极与第三节点N3连接。第四晶体管T4的控制极与第一扫描信号线S1连接，第四晶体管T4的第一极与数据信号线DATA连接，第四晶体管T4的第二极与第一节点N1连接。第五晶体管T5的控制极与发光信号线EM连接，第五晶体管T5的第一极与第二电源线VDD连接，第五晶体管T5的第二极与第一节点N1连接。第六晶体管T6的控制极与发光信号线EM连接，第六晶体管T6 的第一极与第三节点N3连接，第六晶体管T6的第二极与发光器件的第一极连接。第七晶体管T7的控制极与第一扫描信号线S1连接，第七晶体管T7的第一极与第二初始信号线INIT2连接，第七晶体管T7的第二极与发光器件的第一极连接。存储电容C的第一端与第二电源线VDD连接，存储电容C的第二端与第二节点N2连接。
在示例性实施方式中，第一晶体管T1到第七晶体管T7可以是P型晶体管，或者可以是N型晶体管。像素驱动电路中采用相同类型的晶体管可以简化工艺流程，减少显示面板的工艺难度，提高产品的良率。在一些可能的实现方式中，第一晶体管T1到第七晶体管T7可以包括P型晶体管和N型晶体管。
在示例性实施方式中，发光器件的第二极与第一电源线VSS连接，第一电源线VSS的信号为低电平信号，第二电源线VDD的信号为持续提供高电平信号。第一扫描信号线S1为本显示行像素驱动电路中的扫描信号线，第二扫描信号线S2为上一显示行像素驱动电路中的扫描信号线，即对于第n显示行，第一扫描信号线S1为S(n)，第二扫描信号线S2为S(n-1)，本显示行的第二扫描信号线S2与上一显示行像素驱动电路中的第一扫描信号线S1为同一信号线，可以减少显示面板的信号线，实现显示面板的窄边框。
图4为一种显示基板的剖面结构示意图，示意了OLED显示基板三个子像素的结构。如图4所示，在垂直于显示基板的平面上，显示基板了可以包括设置在基底101上的驱动电路层102、设置在驱动电路层102远离基底101一侧的发光器件103以及设置在发光器件103远离基底101一侧的封装层104。在一些可能的实现方式中，显示基板可以包括其它膜层，如隔垫柱等，本公开在此不做限定。
在示例性实施方式中，基底可以是柔性基底，或者可以是刚性基底。柔性基底可以包括叠设的第一柔性材料层、第一无机材料层、半导体层、第二柔性材料层和第二无机材料层，第一柔性材料层和第二柔性材料层的材料可以采用聚酰亚胺(PI)、聚对苯二甲酸乙二酯(PET)或经表面处理的聚合物软膜等材料，第一无机材料层和第二无机材料层的材料可以采用氮化硅 (SiNx)或氧化硅(SiOx)等，用于提高基底的抗水氧能力，半导体层的材料可以采用非晶硅(a-si)。
在示例性实施方式中，每个子像素的驱动电路层102可以包括构成像素驱动电路的多个晶体管和存储电容，图3中以每个子像素中包括一个驱动晶体管和一个存储电容为例进行示意。在一些可能的实现方式中，每个子像素的驱动电路层102可以包括：设置在基底上的第一绝缘层201；设置在第一绝缘层上的有源层；覆盖有源层的第二绝缘层202；设置在第二绝缘层202上的栅电极和第一电容电极；覆盖栅电极和第一电容电极的第三绝缘层203；设置在第三绝缘层203上的第二电容电极；覆盖第二电容电极的第四绝缘层204，第二绝缘层202、第三绝缘层203和第四绝缘层204上开设有过孔，过孔暴露出有源层；设置在第四绝缘层204上的源电极和漏电极，源电极和漏电极分别通过过孔与有源层连接；覆盖前述结构的平坦层205，平坦层205上开设有过孔，过孔暴露出漏电极。有源层、栅电极、源电极和漏电极组成驱动晶体管210，第一电容电极和第二电容电极组成存储电容211。
在示例性实施方式中，发光器件103可以包括阳极301、像素定义层302、有机发光层303和阴极304。阳极301设置在平坦层205上，通过平坦层205上开设的过孔与驱动晶体管210的漏电极连接；像素定义层302设置在阳极301和平坦层205上，像素定义层302上设置有像素开口，像素开口暴露出阳极301；有机发光层303至少部分设置在像素开口内，有机发光层303与阳极301连接；阴极304设置在有机发光层303上，阴极304与有机发光层303连接；有机发光层303在阳极301和阴极304驱动下出射相应颜色的光线。
在示例性实施方式中，封装层104可以包括叠设的第一封装层401、第二封装层402和第三封装层403，第一封装层401和第三封装层403可采用无机材料，第二封装层402可采用有机材料，第二封装层402设置在第一封装层401和第三封装层403之间，可以保证外界水汽无法进入发光器件103。
在示例性实施方式中，OLED发光元件的有机发光层可以包括发光层(Emitting Layer，简称EML)，以及包括空穴注入层(Hole Injection Layer，简称HIL)、空穴传输层(Hole Transport Layer，简称HTL)、空穴阻挡层 (Hole Block Layer，简称HBL)、电子阻挡层(Electron Block Layer，简称EBL)、电子注入层(Electron Injection Layer，简称EIL)、电子传输层(Electron Transport Layer，简称ETL)中的一个或多个膜层。在阳极和阴极的电压驱动下，利用有机材料的发光特性根据需要的灰度发光。
在示例性实施方式中，不同颜色的OLED发光元件的发光层不同。例如，红色发光元件包括红色发光层，绿色发光元件包括绿色发光层，蓝色发光元件包括蓝色发光层。为了降低工艺难度和提升良率，位于发光层一侧的空穴注入层和空穴传输层可以采用共通层，位于发光层另一侧的电子注入层和电子传输层可以采用共通层。在示例性实施方式中，空穴注入层、空穴传输层、电子注入层和电子传输层中的任意一层或多层可以通过一次工艺(一次蒸镀工艺或一次喷墨打印工艺)制作，但通过形成的膜层表面段差或者通过表面处理等手段实现隔离。例如，相邻子像素对应的空穴注入层、空穴传输层、电子注入层和电子传输层中的任意一层或多层可以是隔离的。在示例性实施方式中，有机发光层可以通过采用精细金属掩模版(FMM，Fine Metal Mask)或者开放式掩膜版(Open Mask)蒸镀制备形成，或者采用喷墨工艺制备形成。
一种OLED结构中，蓝色发光元件的使用寿命较短，导致长期使用后白平衡颜色漂移，视觉上会出现开启白色画面时颜色发粉等现象，制约了OLED显示的应用，无法应用于使用寿命较长的设备。虽然研究新的蓝色发光层材料可以提高蓝色发光元件使用寿命，但经过多年发展，从材料方向提升使用寿命不仅成本越来越高，而且提升潜力越来越小。
研究表明，OLED发光元件的性能取决于材料本身性能和器件搭配结构。材料本身性能涉及功材料能级、迁移率、材料稳定性、材料荧光量子产率(PLQY)等，器件搭配结构涉及相邻膜层的能级匹配、激子分布情况、电子和空穴注入情况、电子和空穴堆积情况等。进一步研究表明，OLED发光元件中较容易劣化的材料包括电子阻挡层(也称之为空穴辅助层)。电子阻挡层与蓝色发光层主体材料之间存在较大的能级势垒，导致空穴在电子阻挡层和发光层界面积累，使发光复合区域靠近该界面。图5为一种发光层中激子分布的示意图。如图5所示，由于发光层的激子主要集中在电子阻挡层和 发光层界面0％处，使得过多的电子在该界面的累积。通常，电子阻挡层材料本身一般都是富电子体系(含有芳胺结构)材料，过多的电子会与电子阻挡层本身的富电子产生排斥力的作用，这种排斥力会造成苯胺上的苯环δ键扭曲，外力造成的δ键扭曲的结果就是键的断裂，造成材料缺陷，器件寿命衰减较快。因而，键断裂所产生的缺陷就是材料和器件寿命衰减的根基(即材料的本证劣化)。
图6为本公开示例性实施例一种OLED结构的示意图。如图6所示，OLED包括阳极10、阴极90以及设置在阳极10和阴极90之间有机发光层。在示例性实施方式中，有机发光层可以包括叠设的空穴传输层30、电子阻挡层40、发光层50和空穴阻挡层60，空穴传输层30和电子阻挡层40设置在阳极10与发光层50之间，空穴阻挡层60设置在发光层50与阴极90之间。空穴传输层30设置在靠近阳极10的一侧，电子阻挡层40设置在靠近发光层50的一侧，即空穴传输层30设置在阳极10与电子阻挡层40之间，电子阻挡层40设置在空穴传输层30与发光层50之间。在示例性实施方式中，空穴传输层30被配置为实现注入空穴定向有序的可控迁移，电子阻挡层40被配置为对电子形成迁移势垒，阻止电子从发光层50中迁移出来。发光层50被配置为使电子和空穴发生复合而发出光线。空穴阻挡层60被配置为对空穴形成迁移势垒，阻止空穴从发光层50中迁移出来。在示例性实施方式中，发光层50包括主体(Host)材料和掺杂在主体材料中的客体(Dopant)材料。
图7为本公开示例性实施例一种OLED结构的能级关系示意图。如图7所示，在示例性实施方式中，发光层客体材料的最高占据分子轨道(Highest Occupied Molecular Orbit，简称HOMO)能级HOMO Dopant高于电子阻挡层EBL的HOMO能级HOMO EBL，空穴传输层HTL的HOMO能级HOMO HTL高于电子阻挡层EBL的HOMO能级HOMO EBL，电子阻挡层EBL的HOMO能级HOMO EBL高于发光层主体材料的HOMO能级HOMO Host，发光层主体材料的HOMO能级HOMO Host高于空穴阻挡层HBL的HOMO能级HOMO HBL。空穴阻挡层HBL的最低未占分子轨道(Lowest Unoccupied Molecular Orbital，简称LUMO)LUMO HBL高于发光层客体材料的LUMO能级LUMO Dopant，发光层客体材料的LUMO能级LUMO Dopant高于发光层主体 材料的LUMO能级LUMO Host，电子阻挡层EBL的LUMO能级LUMO EBL高于发光层客体材料的LUMO能级LUMO Dopant，电子阻挡层EBL的LUMO能级LUMO EBL高于空穴传输层HTL的LUMO能级LUMO HTL。在示例性实施方式中，电子阻挡层EBL的LUMO能级LUMO EBL高于空穴阻挡层HBL的LUMO能级LUMO HBL。在示例性实施方式中，空穴阻挡层HBL的最低三重态能量T1 HBL大于发光层客体材料的最低三重态能量T1 Dopant，发光层客体材料的最低三重态能量T1 Dopant大于发光层主体材料的最低三重态能量T1 Host。
在示例性实施方式中，发光层主体材料和发光层客体材料可以满足：
│HOMO Dopant│<│HOMO Host│，│LUMO Dopant│≤│LUMO Host│。
在示例性实施方式中，通过设置发光层主体材料与发光层客体材料之间的HOMO能级和LUMO能级的关系，有利于能量的有效传递。
在示例性实施方式中，发光层主体材料和空穴阻挡层可以满足：
│HOMO HBL-HOMO Host│≥0.5eV，即ΔE2≥0.5eV。
在示例性实施方式中，通过设置空穴阻挡层与发光层主体材料之间的HOMO能级的关系，有利于空穴的阻挡。
在示例性实施方式中，发光层客体材料和空穴阻挡层可以满足：
│HOMO HBL-HOMO Dopant│≥0.9eV，即ΔE1≥0.9eV。
在示例性实施方式中，空穴阻挡层和发光层主体材料可以满足：
│LUMO host│>│LUMO HBL│。
在示例性实施方式中，通过设置空穴阻挡层与发光层主体材料之间的LUMO能级的关系，有利于电子的传输。
在示例性实施方式中，发光层客体材料和空穴阻挡层可以满足：
T1 HBL>T1 Dopant。
其中，T1 HBL为空穴阻挡层的最低三重态能量，T1 Dopant为发光层客体材料的最低三重态能量。
在示例性实施方式中，通过设置发光层客体材料和空穴阻挡层之间的最低三重态能量的关系，有利于激子在发光层中复合发光。
在示例性实施方式中，空穴传输层和电子阻挡层可以满足：
│HOMO HTL-HOMO EBL│<0.3eV，即ΔF1<0.3eV；
0.2eV≤│HOMO EBL-HOMO Host│＜0.5eV，即0.2eV≤ΔF2＜0.5eV。
在示例性实施方式中，通过设置空穴传输层和电子阻挡层之间的HOMO能级的关系、电子阻挡层和发光层主体材料之间的HOMO能级的关系，不仅有利于空穴传输到发光层，而且可以有效降低空穴传输层和发光层主体材料之间的能级势垒ΔF3，ΔF3＝ΔF1+ΔF2＝│HOMO HTL-HOMO Host│，降低器件电压。
在示例性实施方式中，发光层主体材料和空穴阻挡层可以满足：
E HBL≥E host。
其中，E HBL为空穴阻挡层的电子迁移率(Electron Mobility)，E host为发光层主体材料的电子迁移率。
在示例性实施方式中，通过设置空穴阻挡层与发光层主体材料之间的电子迁移率的关系，有利于增加发光层主体材料中电子向空穴阻挡层方向移动的几率，有利于减少电子在发光层与电子阻挡层的交界面处累积，减缓交界面处电子阻挡层材料劣化，使激子复合区域向发光层中心移动。
在示例性实施方式中，空穴传输层和电子阻挡层可以满足：
EK HTL>EK EBL。
其中，EK HTL为空穴传输层的空穴迁移率，EK EBL为电子阻挡层的空穴迁移率。
在示例性实施方式中，通过设置空穴传输层和电子阻挡层之间的空穴迁移率的关系，有利于减少空穴在电子阻挡层与发光层的交界面处累积，减缓交界面处电子阻挡层材料劣化，使激子复合区域向发光层中心移动。
在示例性实施方式中，通过空穴传输层、电子阻挡层、发光层主体材料、发光层客体材料和空穴阻挡层之间的能级搭配、迁移率搭配或者能级和迁移率搭配，有利于能量的有效传递，减少了界面的载流子积累，提高了界面和材料的稳定性，减少了因电子堆积引起的材料劣化和寿命下降，同时有利于载流子传输到发光层中，增加了发光层内部的载流子密度，改善了发光层中 载流子的平衡，有利于激子在发光层中复合发光，使激子复合区域向发光层中心移动，提高效率和使用寿命。
在示例性实施方式中，HOMO Host可以约为-5.70eV至-6.10eV，HOMO Dopant可以约为-5.25eV至-5.50eV，HOMO HBL可以约为-6.10eV至-6.40eV，LUMO Host可以约为-2.70eV至-3.10eV，LUMO Dopant可以约为-2.60eV至-2.80eV，LUMO HBL可以约为-2.55eV至-2.80eV。
在示例性实施方式中，空穴传输层的空穴迁移率EK HTL可以约为10 -4cm 2/Vs至10 -5cm 2/Vs，电子阻挡层的空穴迁移率EK EBL可以约为10 -5cm 2/Vs至10 -7cm 2/Vs。
在示例性实施方式中，空穴阻挡层的电子迁移率E HBL可以约为10 -5cm 2/Vs至10 -8cm 2/Vs，发光层主体材料的电子迁移率E host可以约为10 -6cm 2/Vs至10 -8cm 2/Vs。
在示例性实施方式中，HOMO Host可以约为-5.75eV至-6.05eV，HOMO Dopant可以约为-5.3eV至-5.45eV，HOMO HBL可以约为-6.15eV至-6.35eV，LUMO Host可以约为-2.75eV至-3.05eV，LUMO Dopant可以约为-2.65eV至-2.75eV，LUMO HBL可以约为-2.60eV至-2.75eV。
在示例性实施方式中，HOMO能级和LUMO能级可以采用光电子分光光度仪(AC3/AC2)或者和紫外(UV)光谱等方法进行测试，迁移率可以采用空间电荷限制电流法(SCLC)进行测试，三线态能级(T1)可以采用低温磷光光谱仪(T1＝1240/PL peak)进行测试。
在示例性实施方式中，发光层50的厚度可以约为10nm至60nm。
在示例性实施方式中，空穴阻挡层60的厚度可以约为0.1nm至20nm。
在示例性实施方式中，电子阻挡层40的厚度可以约为5nm至70nm。
在示例性实施方式中，空穴传输层30的厚度可以约为80nm至120nm。
在示例性实施方式中，发光层50和空穴阻挡层60的厚度不同。例如，发光层50的厚度可以大于空穴阻挡层60的厚度。
在示例性实施方式中，发光层50和电子阻挡层40的厚度不同。例如，发光层50的厚度可以大于电子阻挡层40的厚度。
在示例性实施方式中，发光层50的厚度可以约为15nm至30nm，空穴阻挡层60的厚度可以约为5nm至15nm，电子阻挡层40的厚度可以约为5nm至15nm。
在示例性实施方式中，发光层包括主体材料和掺杂在主体材料中的客体材料，发光层客体材料的掺杂比例为1％至20％。在该掺杂比例范围内，一方面发光层主体材料可将激子能量有效转移给发光层客体材料来激发发光层客体材料发光，另一方面发光层主体材料对发光层客体材料进行了“稀释”，有效改善了发光层客体材料分子间相互碰撞、以及能量间相互碰撞引起的荧光淬灭，提高了发光效率和器件寿命。
本公开示例性实施例中，掺杂比例是指客体材料的质量与发光层的质量之比，即质量百分比。在示例性实施方式中，可以通过多源蒸镀工艺共同蒸镀主体材料和客体材料，使主体材料和客体材料均匀分散在发光层中，可以在蒸镀过程中通过控制客体材料的蒸镀速率来调控掺杂比例，或者通过控制主体材料和客体材料的蒸镀速率比来调控掺杂比例。
在示例性实施方式中，发光层为蓝色发光层。通过提高蓝色发光层的发光效率和使用寿命，可较好地改善有机电致发光器件的整体性能。
一种OLED结构中，激子复合区域主要集中在发光层与电子阻挡层的交界面处，使得过多的电子在该界面的累积，由于累积的电子会导致电子阻挡层的材料裂解，因而降低了材料的稳定性和寿命。本公开示例性实施例通过设置发光层主体材料、发光层客体材料和空穴阻挡层的材料之间的能级关系和电子迁移率关系，能够增加发光层主体材料中电子向空穴阻挡层方向移动的几率，有效减少电子在发光层与电子阻挡层的交界面处累积，不仅提高了电子阻挡层的材料稳定性，减少了电子堆积引起的材料劣化和性能下降，提高了寿命，而且使电子在发光层中有效地复合成激子发光，激子复合区域向发光层中心移动，提高了发光效率。
在示例性实施方式中，发光层主体材料可以包括蒽衍生物(包含氚取代化合物)、9,10-(2-萘基)蒽(AND)或2-甲基-9,10-(2-萘基)蒽(MAND)等，具有高荧光量子产率、分子结构的易修饰性及高热稳定性等特点，发光层主体材料的电子迁移率E host可以约为10 -6cm 2/Vs至10 -8cm 2/Vs。
在示例性实施方式中，发光层主体材料可以包括但不限于具有式1-1至式1-3所示结构的化合物：
Figure PCTCN2020138927-appb-000019
其中，D为氚。
在示例性实施方式中，发光层客体材料可以包括但不限于具有式2所示结构的化合物：
Figure PCTCN2020138927-appb-000020
其中，X为氧(O)或硫(S)；Y为N-R7，B(硼)，P(磷)；R1至R3为氢，氘，氟，C1-C4的烷基，C3-C10的环烷基，C1-C30的烷基甲硅烷基，或C6-C10的芳基甲硅烷基；R4、R5为氢，氘，氟，C1-C4的烷基， C3-C10的环烷基，C1-C30的烷基甲硅烷基，或C6-C30的芳基甲硅烷基，取代或未取代的C6-C30的芳基或杂芳基；Ar 1、Ar 2为取代或未取代的C6-C30的芳基或杂芳基；R1至R3可以相同，或者可以不同。
式2所示结构的化合物通过核心(Core)稠合,将Y和N(氮)将芳基或杂芳基连接起来，抑制单键的扭转，分子刚性增加，增加了材料的刚性，减小了非辐射越迁，且基态和激发态结构变化小，斯托克斯位移(Stokes shift)相对较小。由于基态和激发态结构变化小，因而改善了寿命和色纯度(窄化光谱)，且刚性平面骨架有利于量子产率，有利于效率提高。通过氘代、甲硅烷基的引入，可以提高材料的耐热性和耐分解性。
在示例性实施方式中，发光层客体材料可以包括但不限于具有式2-1至式2-9所示结构的化合物：
Figure PCTCN2020138927-appb-000021
Figure PCTCN2020138927-appb-000022
在示例性实施方式中，空穴阻挡层的材料可以包括但不限于具有式3-1所示结构的化合物：
Figure PCTCN2020138927-appb-000023
其中，R1、R2为氢、氘、氟，C1-C4的烷基，C3-C10的环烷基，C1-C30的烷基甲硅烷基，或者C6-C10的芳基甲硅烷基；Ar 1、Ar 2为取代或未取代的C6-C30的芳基或杂芳基，其中一个为至少含有1个氮的杂芳基；R1、R2可以相同，或者可以不同；Ar 1和Ar 2不同。
在示例性实施方式中，空穴阻挡层的材料可以包括但不限于具有式3-2所示结构的化合物：
Figure PCTCN2020138927-appb-000024
其中，L为取代或未取代的C6-C30的芳基或杂芳基；A为取代或未取代的含氮芳杂环，至少含有1个氮原子；R1、R2为甲基，芳基；R1、R2可以相同，或者可以不同。
在示例性实施方式中，空穴阻挡层材料可以包括但不限于具有式3-3至式3-14所示结构的化合物：
Figure PCTCN2020138927-appb-000025
Figure PCTCN2020138927-appb-000026
Figure PCTCN2020138927-appb-000027
Figure PCTCN2020138927-appb-000028
在示例性实施方式中，电子阻挡层的材料可以包括但不限于具有式4-1或式4-2所示结构的化合物：
Figure PCTCN2020138927-appb-000029
其中，L1-L3为单键，C6-C15的芳基；Ar 1、Ar 2为取代或未取代的C6-C40的芳基、芳胺基或芴基，Ar 1和Ar 2为不同基团，其中一个还可以为如式5表示的取代基。
Figure PCTCN2020138927-appb-000030
其中，R1-R5为氢，氘，烷基，环烷基或C6-C36的芳基。
在示例性实施方式中，式4-1和式4-2中，Ar 1和Ar 2中的一个还可以为如式5-1至5-7表示的取代基。
Figure PCTCN2020138927-appb-000031
Figure PCTCN2020138927-appb-000032
式4-1和式4-2所示结构的化合物为非对称结构，可以提高材料的热稳定性，可以抑制结晶，提高薄膜稳定性。在示例性实施方式中，电子阻挡层的空穴迁移率可以约为10 -5cm 2/Vs至10 -7cm 2/Vs。
在示例性实施方式中，电子阻挡层的材料可以包括但不限于具有式4-1-1至式4-1-6所示结构的化合物：
Figure PCTCN2020138927-appb-000033
Figure PCTCN2020138927-appb-000034
在示例性实施方式中，电子阻挡层的材料可以包括但不限于具有式4-2-1至式4-2-6所示结构的化合物：
Figure PCTCN2020138927-appb-000035
Figure PCTCN2020138927-appb-000036
图8为本公开示例性实施例一种电子阻挡层材料的电化学稳定性测试结果，图9为本公开示例性实施例另一种电子阻挡层材料的电化学稳定性测试结果，电化学稳定性采用循环伏安(Cyclic Voltammetry)测试方式。如图8所示，电子阻挡层采用具有式4-1-1所示结构的化合物，该材料具有较好的电化学稳定性。如图9所示，电子阻挡层采用具有式4-1-4所示结构的化合物，该材料具有较好的电化学稳定性。
在示例性实施方式中，电子阻挡层、发光层主体材料、发光层客体材料和空穴阻挡层的材料可以为本领域技术人员已知的满足上述能级关系和迁移率关系的其它材料，本公开在此不做限定。
图10为本公开示例性实施例另一种OLED结构的示意图。如图10所示，OLED包括阳极10、阴极90以及设置在阳极10和阴极90之间有机发光层。在示例性实施方式中，有机发光层可以包括叠设的空穴注入层20、空穴传输层30、电子阻挡层40、发光层50、空穴阻挡层60、电子传输层70和电子注入层80。空穴注入层20、空穴传输层30和电子阻挡层40设置在阳极10与发光层50之间，空穴注入层20与阳极10连接，电子阻挡层40与发光层50连接，空穴传输层30设置在空穴注入层20和电子阻挡层40之间。 空穴阻挡层60、电子传输层70和电子注入层80设置在发光层50与阴极90之间，空穴阻挡层60与发光层50连接，电子注入层80与阴极90连接，电子传输层70设置在空穴阻挡层60和电子注入层80之间。在示例性实施方式中，空穴注入层20被配置为降低从阳极注入空穴的势垒，使空穴能从阳极有效地注入到发光层50中。空穴传输层30被配置为实现注入空穴定向有序的可控迁移。电子阻挡层40被配置为对电子形成迁移势垒，阻止电子从发光层50中迁移出来。发光层50被配置为使电子和空穴发生复合而发出光线。空穴阻挡层60被配置为对空穴形成迁移势垒，阻止空穴从发光层50中迁移出来。电子传输层70被配置为实现注入电子定向有序的可控迁移。电子注入层80被配置为降低从阴极注入电子的势垒，使电子能从阴极有效地注入到发光层50。
在示例性实施方式中，发光层50和空穴阻挡层60的结构和材料与前述实施例的结构和材料相同或相类似，这里不再赘述。
在示例性实施方式中，阳极可以采用具有高功函数的材料。对于底发射型，阳极可以采用透明氧化物材料，如氧化铟锡(ITO)或氧化铟锌(IZO)等，阳极的厚度可以约为80nm至200nm。对于顶发射型，阳极可以采用金属和透明氧化物的复合结构，如Ag/ITO、Ag/IZO或者ITO/Ag/ITO等，阳极中金属层的厚度可以约为80nm至100nm，阳极中透明氧化物的厚度可以约为5nm至20nm，使阳极在可见光区的平均反射率约为85％～95％。
在示例性实施方式中，对于顶发射型OLED，阴极可以采用金属材料，通过蒸镀工艺形成，金属材料可以采用镁(Mg)、银(Ag)或铝(Al)，或者采用合金材料，如Mg:Ag的合金，Mg:Ag比例约为9:1至1:9，阴极的厚度可以约为10nm至20nm，使阴极在波长530nm处的平均透过率约为50％～60％。对于底发射型OLED，阴极可以采用镁(Mg)、银(Ag)、铝(Al)或Mg:Ag的合金，阴极的厚度可以约大于80nm，使阴极具有良好的反射率。
在示例性实施方式中，空穴注入层可以采用无机的氧化物，如钼氧化物、钛氧化物、钒氧化物、铼氧化物、钌氧化物、铬氧化物、锆氧化物、铪氧化物、钽氧化物、银氧化物、钨氧化物或锰氧化物，或者可以采用强吸电 子体系的p型掺杂剂和空穴传输材料的掺杂物，如六氰基六氮杂三亚苯基、2,3,5,6-四氟-7,7',8,8'-四氰基对醌二甲烷(F4-TCNQ)二甲基或者1,2,3-三[(氰基)(4-氰基-2,3,5,6-四氟苯基)亚甲基]环丙烷等。
在示例性实施方式中，空穴注入层的厚度可以约为5nm至20nm。
在示例性实施方式中，空穴传输层可以采用空穴迁移率较高的材料，如具有空穴传输特性的芳胺类化合物，其取代基团可以是咔唑、甲基芴、螺芴、二苯并噻吩或呋喃等，如4,4'-双[N-(1-萘基)-N-苯基氨基]联苯(NPB)、N,N'-双(3-甲基苯基)-N,N'-二苯基-[1,1'-联苯]-4,4'-二胺(TPD)、4-苯基-4'-(9-苯基芴-9-基)三苯基胺(BAFLP)、4,4'-双[N-(9,9-二甲基芴-2-基)-N-苯基氨基]联苯(DFLDPBi)、4,4'-二(9-咔唑基)联苯(CBP)或者9-苯基-3-[4-(10-苯基-9-蒽基)苯基]-9H-咔唑(PCzPA)等。
在示例性实施方式中，空穴传输层的厚度可以约为80nm至120nm，空穴传输层的导电率小于或等于空穴注入层的导电率。
在示例性实施方式中，电子阻挡层可以采用具有空穴传输特性的芳胺类化合物，其取代基团可以是咔唑、甲基芴、螺芴、二苯并噻吩或呋喃等，如4,4'-双[N-(1-萘基)-N-苯基氨基]联苯(NPB)、N,N'-双(3-甲基苯基)-N,N'-二苯基-[1,1'-联苯]-4,4'-二胺(TPD)、4-苯基-4'-(9-苯基芴-9-基)三苯基胺(BAFLP)、4,4'-双[N-(9,9-二甲基芴-2-基)-N-苯基氨基]联苯(DFLDPBi)、4,4'-二(9-咔唑基)联苯(CBP)或者9-苯基-3-[4-(10-苯基-9-蒽基)苯基]-9H-咔唑(PCzPA)等。
在示例性实施方式中，电子阻挡层的厚度可以约为5nm至70nm。电子阻挡层的导电率小于或等于空穴注入层的导电率。
在示例性实施方式中，电子传输层可以采用芳族杂环化合物，例如苯并咪唑衍生物、咪唑并吡啶衍生物、苯并咪唑并菲啶衍生物等咪唑衍生物；嘧啶衍生物、三嗪衍生物等嗪衍生物；喹啉衍生物、异喹啉衍生物、菲咯啉衍生物等，包含含氮六元环结构的化合物(包括在杂环上具有氧化膦系的取代基的化合物)等。例如2-(4-联苯基)-5-(4-叔丁基苯基)-1,3,4-噁二唑(PBD)、1,3-双[5-(对叔丁基苯基)-1,3,4-噁二唑-2-基]苯(OXD-7)、3-(4-叔丁基苯基)-4- 苯基-5-(4-联苯基)-1,2,4-三唑(TAZ)、3-(4-叔丁基苯基)-4-(4-乙基苯基)-5-(4-联苯基)-1,2,4-三唑(p-EtTAZ)、红菲咯啉(BPhen)、浴铜灵(BCP)或者4,4'-双(5-甲基苯并噁唑-2-基)芪(BzOs)等。
在示例性实施方式中，电子传输层的厚度可以约为20nm至50nm。
在示例性实施方式中，电子注入层可以采用碱金属或者金属，例如氟化锂(LiF)、镱(Yb)、镁(Mg)或钙(Ca)等材料，或者这些碱金属或者金属的化合物等。
在示例性实施方式中，电子注入层的厚度可以约为0.5nm至5nm。
在示例性实施方式中，OLED可以包括封装层，封装层可以采用盖板封装，或者可以采用薄膜封装。
在示例性实施方式中，对于顶发射型OLED，阴极和阳极之间的有机发光层的厚度可以按照满足光学微谐振腔的光程要求设计，以获得最优的出光强度和颜色。
在示例性实施方式中，可以采用如下制备方法制备包括OLED结构的显示基板。首先，通过图案化工艺在基底上形成驱动电路层，每个子像素的驱动电路层可以包括构成像素驱动电路的驱动晶体管和存储电容。随后，在形成前述结构的基底上形成平坦层，每个子像素的平坦层上形成有暴露出驱动晶体管的漏电极的过孔。随后，在形成前述结构的基底上，通过图案化工艺形成阳极，每个子像素的阳极通过平坦层上的过孔与驱动晶体管的漏电极连接。随后，在形成前述结构的基底上，通过图案化工艺形成像素定义层，每个子像素的像素定义层上形成有暴露出阳极的像素开口，每个像素开口作为每个子像素的发光区域。随后，在形成前述结构的基底上，先采用开放式掩膜版依次蒸镀空穴注入层和空穴传输层，在显示基板上形成空穴注入层和空穴传输层的共通层，即所有子像素的空穴注入层是连通的，所有子像素的空穴传输层是连通的。空穴注入层的厚度可以约为5nm至20nm，空穴传输层的厚度可以约为80nm至120nm。例如，空穴注入层和空穴传输层各自的面积大致是相同的，厚度不同。随后，采用精细金属掩模版在不同的子像素分别蒸镀电子阻挡层和红色发光层、电子阻挡层和绿色发光层、以及电子阻挡 层和蓝色发光层，相邻子像素的电子阻挡层和发光层是可以有少量的交叠(例如，交叠部分占各自发光层图案的面积小于10％)，或者可以是隔离的。电子阻挡层的厚度可以约为5nm至70nm，发光层的厚度可以约为10nm至60nm。随后，采用开放式掩膜版依次蒸镀空穴阻挡层、电子传输层、电子注入层和阴极，在显示基板上形成空穴阻挡层、电子传输层、电子注入层和阴极的共通层，即所有子像素的空穴阻挡层是连通的，所有子像素的电子传输层是连通的，所有子像素电子注入层的是连通的，所有子像素的阴极是连通的。空穴阻挡层的厚度可以约为0.1nm至20nm，电子传输层的厚度可以约为20nm至50nm。
在示例性实施方式中，蓝色发光层包括蓝光主体材料(BH)和蓝光客体材料(BD)，掺杂比例可以约为1％至20％。蒸镀蓝色发光层可以采用多源共蒸镀方式，形成包含主体材料和客体材料的发光层，可以在蒸镀过程中通过控制客体材料的蒸镀速率来调控掺杂比例，或者通过控制主体材料和客体材料的蒸镀速率比来调控掺杂比例。
在示例性实施方式中，空穴注入层、空穴传输层、空穴阻挡层、电子传输层、电子注入层和阴极中的一层或多层在基底上的正投影是连续的。在一些示例中，至少一行或一列的子像素的空穴注入层、空穴传输层、空穴阻挡层、电子传输层、电子注入层和阴极中的至少一层是连通的。在一些示例中，多个子像素的空穴注入层、空穴传输层、空穴阻挡层、电子传输层、电子注入层和阴极中的至少一层是连通的。
在示例性实施方式中，有机发光层可以包括位于空穴传输层和发光层之间的微腔调节层。例如，可以在形成空穴传输层之后，采用精细金属掩模版在不同的子像素分别蒸镀红色微腔调节层和红色发光层、绿色微腔调节层和绿色发光层、以及蓝色微腔调节层和蓝色发光层。在示例性实施方式中，红色微腔调节层、绿色微腔调节层和蓝色微腔调节层可以包括电子阻挡层。
在示例性实施方式中，由于空穴阻挡层是共通层，而不同子像素的发光层是隔离的，因而空穴阻挡层在基板上的正投影包含发光层在基板上的正投影，空穴阻挡层的面积大于发光层的面积。
在示例性实施方式中，由于空穴阻挡层是共通层，因而空穴阻挡层在基 板上的正投影至少包括两个子像素的发光区域在基板上的正投影。
在示例性实施方式中，至少部分子像素的发光层在基板上的正投影与像素驱动电路驱动在基板上的正投影有交叠。
表1为本公开示例性实施例几种膜层材料组合结构的性能比较结果。对比实验中，对比结构1、结构1至结构6的有机发光层的结构均为HIL/HTL/EBL/BEML/HBL/ETL，对比结构1、结构1至结构6的相应膜层的厚度相同，对比结构1、结构1至结构6的空穴注入层HIL、空穴传输层HTL、电子阻挡层EBL和电子传输层ETL的材料和厚度相同，对比结构1、结构1至结构6的蓝光主体材料相同。
对比结构1、结构1至结构6中材料相同膜层的相关材料为：
Figure PCTCN2020138927-appb-000037
Figure PCTCN2020138927-appb-000038
对比实验中，对比结构1、结构1至结构6的蓝光发光层BEML均包括蓝光主体材料和蓝光客体材料，掺杂比例均为3％。对比结构1、结构1至结构6的蓝光客体材料不同，对比结构1、结构1至结构6的空穴阻挡层HBL的材料不同。对比结构1、结构1至结构6的蓝光客体材料和空穴阻挡层HBL的材料为：
Figure PCTCN2020138927-appb-000039
Figure PCTCN2020138927-appb-000040
Figure PCTCN2020138927-appb-000041
Figure PCTCN2020138927-appb-000042
表1、几种不同发光层客体材料和空穴阻挡层材料的性能比较结果
  电压 效率 寿命
对比结构1 100％ 100％ 100％
结构1 96％ 120％ 118％
结构2 94％ 131％ 126％
结构3 98％ 118％ 109％
结构4 93％ 113％ 128％
结构5 95％ 118％ 104％
结构6 97％ 122 121％
图11为几种不同客体材料和空穴阻挡层材料组合的寿命示意图。如表1和图11所示，与对比结构1相比，结构1至结构6在降低电压、提升效率和提升寿命等方面均具有明显的提升，在相同的时间，结构1至结构6的寿命减小幅度均小于对比结构1的寿命减小幅度。结构2和结构4的蓝光客体材料中含有三甲基硅取代，材料热稳定性较高，因而结构2和结构4的寿命增加程度较大于结构5的寿命增加程度。结构2和结构4的空穴阻挡层的材料为相对长寿命类材料，虽然结构3的蓝光客体材料中含有三甲基硅取代，但由于采用不同的空穴阻挡层的材料，因而结构3的寿命增加程度低于结构2 和结构4的寿命增加程度。结构2和结构6的空穴阻挡层的材料的迁移率较大，因而结构2和结构6的效率增加程度较大于其它结构的效率增加程度。结构2中主体材料、客体材料和空穴阻挡层的材料的能级搭配更加合理，因而效率增加程度更大。本公开示例性实施例通过合理搭配发光层主体材料、发光层客体材料和空穴阻挡层的材料的能级关系以及迁移率关系，能够增加发光层主体材料中电子向空穴阻挡层方向移动的几率，有效减少电子在发光层与电子阻挡层的交界面处累积，不仅提高了电子阻挡层的材料稳定性，减少了电子堆积引起的材料劣化和性能下降，提高了寿命，而且使空穴-电子对更有效在发光层中复合发光，激子复合区域向发光层中心移动，提高了发光效率。本公开示例性实施例通过优化客体材料和空穴阻挡层材料，有效提升了材料的结晶性和稳定性，避免了因材料劣化造成的寿命衰减，最大限度地提高了器件寿命。
图12为不同客体材料膜的光谱图。由结构1的蓝光客体材料蒸镀形成的结构1材料膜用实线表示，由对比结构1的蓝光客体材料蒸镀形成的对比结构材料膜用虚线表示，荧光光谱通过荧光光谱仪测试。如图12所示，本公开提出的蓝光客体材料相对于对比结构的蓝光客体材料，具有更窄的发射光谱，有利于色纯度提高。
表2为本公开示例性实施例另几种膜层材料组合结构的性能比较结果。对比实验中，对比结构2、结构7至结构10的有机发光层的结构均为HIL/HTL/EBL/BEML/HBL/ETL，对比结构2、结构7至结构10的相应膜层的厚度相同，对比结构2、结构7至结构10的空穴注入层HIL、空穴传输层HTL、空穴阻挡层HBL和电子传输层ETL的材料和厚度相同，对比结构2、结构7至结构10的蓝光客体材料相同。
对比结构2、结构7至结构10中材料相同膜层的相关材料为：
Figure PCTCN2020138927-appb-000043
Figure PCTCN2020138927-appb-000044
Figure PCTCN2020138927-appb-000045
对比实验中，对比结构2、结构7至结构10的蓝光发光层BEML均包括蓝光主体材料和蓝光客体材料，掺杂比例均为5％。对比结构2、结构7至结构10的电子阻挡层EBL的材料不同，蓝光客体材料不同。对比结构2、结构7至结构10电子阻挡层EBL的材料和蓝光客体材料为：
Figure PCTCN2020138927-appb-000046
Figure PCTCN2020138927-appb-000047
表2、几种不同电子阻挡层和发光层客体材料的性能比较结果
  电压 效率 寿命
对比结构2 100％ 100％ 100％
结构7 96％ 115％ 118％
结构8 95％ 118％ 121％
结构9 94％ 130％ 132％
结构10 93％ 124％ 122％
如表2所示，与对比结构2相比，结构7至结构10在降低电压、提升效率和提升寿命等方面均具有明显的提升，且通过不同电子阻挡层和发光层客体材料的组合，寿命得到明显提升。
本公开示例性实施例通过合理搭配电子阻挡层和发光层客体材料的能级关系以及迁移率关系，有利于能量的有效传递，减少了界面的载流子积累，提高了界面和材料的稳定性，减少了因电子堆积引起的材料劣化和寿命下降，同时有利于载流子传输到发光层中，增加了发光层内部的载流子密度，改善了发光层中载流子的平衡，有利于激子在发光层中复合发光，使激子复合区域向发光层中心移动，提高效率和使用寿命。本公开示例性实施例通过优化电子阻挡层和发光层客体材料，结合高效率稳定性好的电子阻挡层和发光层客体材料，有效提升了材料的结晶性和稳定性，避免了因材料劣化造成的寿命衰减，最大限度地提高了蓝光发光器件寿命。
本公开还提供了一种显示装置，包括前述的有机电致发光器件。显示装置可以为手机、平板电脑、电视机、显示器、笔记本电脑、数码相框、导航仪、车载显示器、智能手表、智能手环等任何具有显示功能的产品或部件。
虽然本公开所揭露的实施方式如上，但所述的内容仅为便于理解本公开而采用的实施方式，并非用以限定本公开。任何所属领域内的技术人员，在不脱离本公开所揭露的精神和范围的前提下，可以在实施的形式及细节上进行任何的修改与变化，但本申请的专利保护范围，仍须以所附的权利要求书所界定的范围为准。

Claims (23)

  1. 一种有机电致发光器件，包括阳极、阴极以及设置在所述阳极和阴极之间的发光层，所述发光层包括主体材料和掺杂在所述主体材料中的客体材料；所述主体材料和客体材料满足：
    │HOMO Dopant│<│HOMO Host│，│LUMO Dopant│≤│LUMO Host│；
    其中，HOMO Dopant为所述客体材料的最高占据分子轨道HOMO能级，HOMO Host为所述主体材料的HOMO能级，LUMO Dopant为所述客体材料最低未占分子轨道LUMO能级，LUMO host为所述主体材料的LUMO能级。
  2. 根据权利要求1所述的有机电致发光器件，其中，所述发光层和阴极之间还设置有空穴阻挡层，所述主体材料、客体材料和空穴阻挡层满足：
    │HOMO HBL-HOMO Host│≥0.5eV，
    其中，HOMO HBL为所述空穴阻挡层的HOMO能级。
  3. 根据权利要求2所述的有机电致发光器件，其中，所述客体材料和空穴阻挡层满足：
    │HOMO HBL-HOMO Dopant│≥0.9eV。
  4. 根据权利要求2所述的有机电致发光器件，其中，所述主体材料和空穴阻挡层满足：
    E HBL≥E host，
    其中，E HBL为所述空穴阻挡层的电子迁移率，E host为所述主体材料的电子迁移率。
  5. 根据权利要求4所述的有机电致发光器件，其中，所述空穴阻挡层的电子迁移率E HBL为10 -5cm 2/Vs至10 -8cm 2/Vs，所述主体材料的电子迁移率E host为10 -6cm 2/Vs至10 -8cm 2/Vs。
  6. 根据权利要求2所述的有机电致发光器件，其中，所述主体材料和空穴阻挡层满足：
    │LUMO host│>│LUMO HBL│
    其中，LUMO HBL为所述空穴阻挡层的LUMO能级。
  7. 根据权利要求2所述的有机电致发光器件，其中，所述客体材料和空穴阻挡层的材料满足：
    T1 HBL>T1 Dopant，
    其中，T1 HBL为所述空穴阻挡层的最低三重态能量，T1 Dopant为所述客体材料的最低三重态能量。
  8. 根据权利要求1至7任一项所述的有机电致发光器件，其中，所述阳极和发光层之间还设置有空穴传输层和电子阻挡层，所述空穴传输层和电子阻挡层满足：
    │HOMO HTL-HOMO EBL│<0.3eV，
    其中，HOMO HTL为所述空穴传输层的HOMO能级，HOMO EBL为所述电子阻挡层的HOMO能级。
  9. 根据权利要求8所述的有机电致发光器件，其中，所述电子阻挡层和主体材料满足：
    0.2eV≤│HOMO EBL-HOMO Host│＜0.5eV。
  10. 根据权利要求8所述的有机电致发光器件，其中，所述空穴传输层和电子阻挡层满足：
    EK HTL>EK EBL，
    其中，EK HTL为所述空穴传输层的空穴迁移率，EK EBL为所述电子阻挡层的空穴迁移率。
  11. 根据权利要求10所述的有机电致发光器件，其中，所述空穴传输层的空穴迁移率为10 -4cm 2/Vs至10 -5cm 2/Vs，所述电子阻挡层的空穴迁移率为10 -5cm 2/Vs至10 -7cm 2/Vs。
  12. 根据权利要求1至7任一项所述的有机电致发光器件，其中，所述主体材料包括蒽衍生物、9，10-(2-萘基)蒽或2-甲基-9，10-(2-萘基)蒽。
  13. 根据权利要求1至7任一项所述的有机电致发光器件，其中，所述主体材料包括如下具有如下结构式的化合物的一种或多种：
    Figure PCTCN2020138927-appb-100001
    其中，D为氚。
  14. 根据权利要求1至7任一项所述的有机电致发光器件，其中，所述客体材料包括具有如下结构式的化合物：
    Figure PCTCN2020138927-appb-100002
    其中，X为O或S；Y为N-R7，B，P；R1至R3为氢，氘，氟，C1-C4的烷基，C3-C10的环烷基，C1-C30的烷基甲硅烷基，或C6-C10的芳基甲硅烷基；R4、R5为氢，氘，氟，C1-C4的烷基，C3-C10的环烷基，C1-C30的烷基甲硅烷基，或C6-C30的芳基甲硅烷基，取代或未取代的C6-C30的芳基或杂芳基；Ar 1、Ar 2为取代或未取代的C6-C30的芳基或杂芳基；R1至R3 相同或者不同。
  15. 根据权利要求1至7任一项所述的有机电致发光器件，其中，所述客体材料包括具有如下结构式的化合物的一种或多种：
    Figure PCTCN2020138927-appb-100003
    Figure PCTCN2020138927-appb-100004
  16. 根据权利要求1至7任一项所述的有机电致发光器件，其中，所述空穴阻挡层包括但不限于具有如下式所示结构的化合物：
    Figure PCTCN2020138927-appb-100005
    其中，R1、R2为氢、氘、氟，C1-C4的烷基，C3-C10的环烷基，C1-C30的烷基甲硅烷基，或者C6-C10的芳基甲硅烷基；Ar 1、Ar 2为取代或未取代的C6-C30的芳基或杂芳基，其中一个为至少含有1个氮的杂芳基；R1、R2相同或者不同；Ar 1和Ar 2不同。
  17. 根据权利要求1至7任一项所述的有机电致发光器件，其中，所述空穴阻挡层包括但不限于具有如下结构式的化合物：
    Figure PCTCN2020138927-appb-100006
    其中，L为取代或未取代的C6-C30的芳基或杂芳基；A为取代或未取代的含氮芳杂环，至少含有1个氮原子；R1、R2为甲基，芳基；R1、R2相同或者不同。
  18. 根据权利要求1至7任一项所述的有机电致发光器件，其中，所述 空穴阻挡层包括具有如下结构式的化合物的一种或多种：
    Figure PCTCN2020138927-appb-100007
    Figure PCTCN2020138927-appb-100008
    Figure PCTCN2020138927-appb-100009
  19. 根据权利要求8至11任一项所述的有机电致发光器件，其中，所述电子阻挡层的材料包括但不限于具有如下结构式的化合物中的任意一种：
    Figure PCTCN2020138927-appb-100010
    其中，L1-L3为单键，C6-C15的芳基；Ar 1、Ar 2为取代或未取代的C6-C40的芳基、芳胺基或芴基，Ar 1和Ar 2为不同基团。
  20. 根据权利要求19所述的有机电致发光器件，其中，所述电子阻挡层的材料包括具有如下结构式的化合物的一种或多种：
    Figure PCTCN2020138927-appb-100011
    Figure PCTCN2020138927-appb-100012
    Figure PCTCN2020138927-appb-100013
  21. 根据权利要求19所述的有机电致发光器件，其中，Ar 1和Ar 2中的一个为具有如下结构式表示的取代基：
    Figure PCTCN2020138927-appb-100014
    其中，R1-R5为氢，氘，烷基，环烷基或C6-C36的芳基。
  22. 根据权利要求19所述的有机电致发光器件，其中，Ar 1和Ar 2中的一个为具有如下结构式表示的取代基：
    Figure PCTCN2020138927-appb-100015
  23. 一种显示装置，包括权利要求1至22任一项所述的有机电致发光器件。
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CN109671851B (zh) * 2017-10-16 2021-10-22 北京鼎材科技有限公司 一种有机电致发光器件
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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