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WO2023206676A1 - 显示面板 - Google Patents

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Publication number
WO2023206676A1
WO2023206676A1 PCT/CN2022/094905 CN2022094905W WO2023206676A1 WO 2023206676 A1 WO2023206676 A1 WO 2023206676A1 CN 2022094905 W CN2022094905 W CN 2022094905W WO 2023206676 A1 WO2023206676 A1 WO 2023206676A1
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WO
WIPO (PCT)
Prior art keywords
light
layer
emitting
display panel
sub
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PCT/CN2022/094905
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English (en)
French (fr)
Inventor
夏国奇
金武谦
Original Assignee
武汉华星光电半导体显示技术有限公司
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Application filed by 武汉华星光电半导体显示技术有限公司 filed Critical 武汉华星光电半导体显示技术有限公司
Priority to US17/781,055 priority Critical patent/US20240206204A1/en
Publication of WO2023206676A1 publication Critical patent/WO2023206676A1/zh

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    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
    • H10K50/11—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K71/00—Manufacture or treatment specially adapted for the organic devices covered by this subclass
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K2101/00—Properties of the organic materials covered by group H10K85/00
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K2101/00—Properties of the organic materials covered by group H10K85/00
    • H10K2101/30—Highest occupied molecular orbital [HOMO], lowest unoccupied molecular orbital [LUMO] or Fermi energy values
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K2101/00—Properties of the organic materials covered by group H10K85/00
    • H10K2101/40—Interrelation of parameters between multiple constituent active layers or sublayers, e.g. HOMO values in adjacent layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K2102/00—Constructional details relating to the organic devices covered by this subclass
    • H10K2102/301—Details of OLEDs
    • H10K2102/351—Thickness

Definitions

  • the present application relates to the field of display technology, and in particular to a display panel.
  • OLED display panels have the characteristics of self-illumination, fast response, wide viewing angle, etc., and have very broad application prospects.
  • Embodiments of the present application provide a display panel for improving the service life of the display panel.
  • An embodiment of the present application provides a display panel, which includes:
  • a first electrode arranged on the substrate
  • a light-emitting layer is provided on a side of the first electrode away from the substrate.
  • the light-emitting layer includes a hole injection sub-layer, a hole transport sub-layer, a light-emitting sub-layer, an electron transport sub-layer, and an electron transport sub-layer that are stacked in sequence.
  • a second electrode disposed on a side of the light-emitting layer away from the substrate
  • the film density parameter of the light-emitting sub-layer is greater than or equal to the first threshold, and the film density parameter is determined by the deformation amount of the film under unit stress condition.
  • the film density parameter is determined by the thickness deformation amount produced by the stressed part of the film under the unit stress condition in the thickness direction of the film. .
  • the film density parameter can be calculated by the following formula:
  • ⁇ F is the difference of different forces in the thickness direction of the film
  • ⁇ H is the thickness difference of the stressed part of the film under different forces.
  • the first threshold is -1.7
  • the film density parameter of the light-emitting sublayer is less than 0.
  • the ratio between the size deformation amplitude of the light-emitting sub-layer and the original shape and size of the light-emitting sub-layer when the display panel is powered on is less than or equal to 5%.
  • the ratio between the thickness expansion amplitude of the light-emitting sub-layer and the original thickness of the light-emitting sub-layer when the display panel is powered on is less than or equal to 5 %.
  • the ratio between the dimensional deformation amplitude of the light-emitting sub-layer and the original shape and size of the light-emitting sub-layer in a heated state is less than or equal to 10%.
  • the ratio between the thickness expansion amplitude of the light-emitting sub-layer in a heated state and the original thickness of the light-emitting sub-layer is less than or equal to 10%.
  • the energy levels of the highest occupied orbitals of the hole transport sublayer, the light emitting sublayer and the electron transport sublayer decrease in sequence
  • the hole transport sublayer The energy levels of the lowest unoccupied orbitals of the sub-layer, the light-emitting sub-layer and the electron-transporting sub-layer decrease in sequence.
  • the energy level difference between the highest occupied orbitals of the hole transport sublayer and the light emitting sublayer is less than or equal to 0.2eV, and the electron transport sublayer and the light emitting sublayer The energy level difference of the lowest empty orbital of the sublayer is less than or equal to 0.2eV.
  • the luminescent sublayer includes blue phosphorescent luminescent material or blue fluorescent luminescent material.
  • the luminescent sublayer includes red phosphorescent luminescent material or red fluorescent luminescent material.
  • the luminescent sublayer includes green phosphorescent luminescent material or green fluorescent luminescent material.
  • the first electrode is an anode
  • the second electrode is a cathode
  • An embodiment of the present application provides a display panel, which includes:
  • a first electrode arranged on the substrate
  • a light-emitting layer is provided on a side of the first electrode away from the substrate.
  • the light-emitting layer includes a hole injection sub-layer, a hole transport sub-layer, a light-emitting sub-layer, an electron transport sub-layer, and an electron transport sub-layer that are stacked in sequence.
  • a second electrode disposed on a side of the light-emitting layer away from the substrate
  • the film density parameter of the light-emitting sub-layer is greater than or equal to the first threshold, the film density parameter is determined by the deformation amount of the film under unit stress condition, and the film density parameter is characterized by an atomic force microscope.
  • the film density parameter is determined by the thickness deformation amount produced by the stressed part of the film under the unit stress condition in the thickness direction of the film. .
  • the film density parameter can be calculated by the following formula:
  • ⁇ F is the difference of different forces in the thickness direction of the film
  • ⁇ H is the thickness difference of the stressed part of the film under different forces.
  • the first threshold is -1.7
  • the film density parameter of the light-emitting sublayer is less than 0.
  • the ratio between the thickness expansion amplitude of the light-emitting sub-layer and the original thickness of the light-emitting sub-layer when the display panel is powered on is less than or equal to 5 %.
  • the ratio between the thickness expansion amplitude of the light-emitting sub-layer in a heated state and the original thickness of the light-emitting sub-layer is less than or equal to 10%.
  • Embodiments of the present application provide a display panel, which includes a substrate, a first electrode, a light-emitting layer, and a second electrode.
  • the first electrode is arranged on the substrate.
  • the light-emitting layer is disposed on a side of the first electrode away from the substrate.
  • the light-emitting layer includes a hole injection sub-layer, a hole transport sub-layer, a light-emitting sub-layer, an electron transport sub-layer and an electron injection sub-layer which are sequentially stacked on the first electrode.
  • the film density parameter of the light-emitting sub-layer is greater than or equal to the first threshold, and the film density parameter is determined by the deformation amount of the film under unit stress condition.
  • the inventor of this application found that when the film density parameter of the light-emitting sublayer is greater than or equal to the first threshold, the film density parameter is positively related to the life of the display panel. The greater the film density parameter, the higher the film density, and the display The panel lasts longer.
  • Figure 1 is a schematic structural diagram of a display panel provided by an embodiment of the present application.
  • Figure 2 is a schematic diagram of using an atomic force microscope to characterize the film density parameters of the light-emitting sublayer in this embodiment
  • Figure 3 is a linear relationship fitted by the host material using mCP as the light-emitting sublayer provided by the embodiment of the present application;
  • Figure 4 is the chemical structural formula of the organic light-emitting material provided by the embodiment of the present application.
  • FIG. 5 is an energy level arrangement diagram of a display panel provided by an embodiment of the present application.
  • first and second are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features.
  • features defined as “first” and “second” may explicitly or implicitly include one or more of the described features.
  • “plurality” means two or more than two, unless otherwise explicitly and specifically limited.
  • An embodiment of the present application provides a display panel. Each is explained in detail below. It should be noted that the order of description of the following embodiments does not limit the preferred order of the embodiments.
  • FIG. 1 is a schematic structural diagram of a display panel according to an embodiment of the present application.
  • An embodiment of the present application provides a display panel.
  • the display panel 100 includes a substrate 101, a first electrode 102, a light-emitting layer 103, and a second electrode 104.
  • the first electrode 102 is provided on the substrate 101.
  • the light-emitting layer 103 is provided on the side of the first electrode 102 away from the substrate 101 .
  • the light-emitting layer 103 includes a hole injection sub-layer 1031, a hole transport sub-layer 1032, a light-emitting sub-layer 1033, an electron transport sub-layer 1034 and an electron injection sub-layer 1035 which are sequentially stacked on the first electrode 102.
  • the film density parameter of the light-emitting sublayer 1033 is greater than or equal to the first threshold, and the film density parameter is determined by the deformation amount of the film under unit stress condition.
  • the inventor of the present application found that when the film density parameter of the light-emitting sublayer 1033 is greater than or equal to the first threshold, the film density parameter is positively correlated with the life of the display panel 100.
  • the greater the film density parameter the higher the film density. , the longer the life of the display panel 100 is.
  • the film density parameter is related to the film density. The higher the film density, the greater the film density parameter and the longer the life of the display panel 100 .
  • the unit force includes but is not limited to the force exerted on the light-emitting sub-layer 1033.
  • the unit force here refers to the smallest unit force exerted on the light-emitting sub-layer 1033 for measurement purposes. , such as 1N, 2N, 5N, 10N, etc.
  • the amount of deformation produced by the film includes but is not limited to the amount of deformation of the thickness of the film.
  • the film density parameter is determined by the thickness deformation amount produced by the stressed part of the film under unit stress conditions in the thickness direction of the film.
  • the film density parameter can be calculated by the following formula: The thickness difference of the part under different forces, 0>X ⁇ -1.7N/cm.
  • the first threshold is -1.7.
  • the film density parameter is greater than or equal to -1.7 and less than 0, the greater the film density parameter, the higher the density of the film and the longer the life of the display panel 100 .
  • ⁇ F can be the difference between two different forces applied to the same force-bearing part, and ⁇ H is the difference in thickness corresponding to the two different forces.
  • ⁇ F is the difference in force applied to two different force-bearing parts, and ⁇ H is the difference in thickness corresponding to the two different forces.
  • an atomic force microscope can be used to characterize the film density parameters of the light-emitting sublayer 1033.
  • an atomic force microscope is used to characterize the luminescent sub-layer 1033, and then a linear relationship is established between the thickness of the luminescent sub-layer 1033 and the force of the atomic force microscope probe that the luminescent sub-layer 1033 receives.
  • the greater the slope of the linear relationship. the greater the density of the thin film of the light-emitting sublayer 1033, the longer the life of the display panel 100.
  • FIG. 2 is a schematic diagram of using an atomic force microscope to characterize the film density parameters of the light-emitting sublayer in this embodiment.
  • Evaluating the film density parameters of the light-emitting sub-layer 1033 specifically includes characterizing the light-emitting sub-layer 1033 using an atomic force microscope.
  • the process of characterizing the luminescent sub-layer 1033 with an atomic force microscope may include arranging the luminescent sub-layer 1033 on the substrate S, and then using the probe P to detect the relative thickness of the luminescent sub-layer 1033.
  • disposing the light-emitting sublayer 1033 on the substrate S includes disposing a polyimide layer PI on the substrate S, and the polyimide layer PI covers a part of the substrate S.
  • a luminescent sub-layer 1033 is evaporated on the substrate S.
  • the luminescent sub-layer 1033 covers the polyimide layer PI and the substrate S.
  • the polyimide layer PI is then peeled off, thereby producing a luminescent sub-layer on the substrate S.
  • Layer 1033 may include arranging the luminescent sub-layer 1033 on the substrate S, and then using the probe P to detect the relative thickness of the luminescent sub-layer 1033.
  • disposing the light-emitting sublayer 1033 on the substrate S includes disposing
  • the light-emitting sub-layer 1033 only covers a part of the substrate S, thereby forming a height difference, which is used to measure the relative thickness of the light-emitting sub-layer 1033.
  • the steps of using the probe P to detect the relative thickness of the luminescent sub-layer 1033 include: first, randomly selecting any point on the luminescent sub-layer 1033, the probe P applying a first force to it, and then using the first force probe P is applied to the substrate S, and the first relative thickness of the light-emitting sublayer 1033 is measured.
  • the probe P applies a second force to it, and then the probe P is applied to the substrate S using the second force to measure the second relative thickness of the luminescent sub-layer 1033 .
  • the third relative thickness of the light-emitting sub-layer 1033 is measured using the third acting force
  • the fourth relative thickness of the light-emitting layer is measured using the fourth acting force.
  • the Nth relative thickness of the light-emitting sublayer 1033 is measured using the Nth force.
  • the slope of the fitted linear relationship is used as the density parameter of the thin film of the light-emitting sublayer 1033. The greater the slope, the greater the film density of the light-emitting sublayer 1033, and the longer the life of the display panel 100.
  • the thickness of the light-emitting sub-layer 1033 decreases as the force exerted by the probe P on the light-emitting sub-layer 1033 increases.
  • the greater the force exerted by the probe P on the light-emitting sub-layer 1033 the smaller the thickness of the corresponding light-emitting sub-layer 1033.
  • the force exerted by the probe P on the light-emitting sub-layer 1033 is used as the abscissa to emit light.
  • the thickness of sub-layer 1033 is the ordinate, and the corresponding linear relationship is obtained by fitting.
  • Figure 3 is a linear relationship fitted by the luminescent host material using mCP (N,N-dicarbazolyl-3,5-benzene) as the luminescent sublayer provided by the embodiment of the present application.
  • the force (F) of the probe received by the luminescent sub-layer 1033 is used as the abscissa
  • the thickness (T) of the luminescent sub-layer 1033 is used as the ordinate
  • the slope of the fitted linear relationship is used as the luminescence Film density parameter for sublayer 1033, where the slope is -1.69.
  • the embodiment of the present application uses 10 different organic light-emitting materials as the host material of the light-emitting sub-layer 1033 to evaluate the film-forming density and light-emitting performance of the light-emitting sub-layer 1033.
  • Figure 4 is a chemical structural formula of an organic light-emitting material provided in an embodiment of the present application.
  • Organic light-emitting materials include DCB, CBP, CDBP, CBPE, mCP, BCzph, CzC, 4CzPBP, TPBi, BCzTPM, BCPPA, NPB, TAPC and Firpic.
  • Table 1 shows the film density parameters and the performance test results of the display panel using 10 different organic light-emitting materials as the host material of the light-emitting sublayer.
  • the luminescent sub-layer 1033 and the display panel 100 were prepared using different organic luminescent materials as host materials. Under the characterization of an atomic force microscope, the greater the slope, the thinner the luminescent sub-layer 1033. The greater the density. As the film density of the light-emitting sublayer 1033 increases, the voltage and electroluminescence peak (EL Peak) are less affected, the external quantum efficiency (EQE) is slightly improved, and the lifetime improvement is very significant. It is proved that the higher the density of the film of the light-emitting sublayer 1033, the more beneficial it is to the light-emitting performance of the blue phosphorescent material.
  • the slope is measured by using the above-mentioned atomic force microscope to act on the thin film of the light-emitting sublayer 1033.
  • the first threshold can also be selected from -1.65, -1.6, -1.55, -1.5, -1.45, -1.4, -1.35, -1.3, -1.25, -1.2, -1.15, etc.
  • the lifespan of blue phosphorescent materials is particularly short, resulting in a reduction in the overall lifespan and reliability of the display panel 100 .
  • taking blue phosphorescent material as an example by increasing the film density of the blue phosphorescent material, the life and reliability of the display panel 100 of the blue phosphorescent material are improved, thereby improving market competitiveness.
  • the light-emitting sublayer 1033 includes, but is not limited to, a blue phosphorescent light-emitting material or a blue fluorescent light-emitting material.
  • the luminescent sub-layer 1033 may also be red phosphorescent luminescent material and green phosphorescent luminescent material, red fluorescent luminescent material and green fluorescent luminescent material.
  • an atomic force microscope is used to characterize the luminescent sub-layer 1033, and a linear relationship between the thickness of the luminescent sub-layer 1033 and the force of the probe of the atomic force microscope received by the luminescent sub-layer 1033 is established.
  • the slope of the linear relationship is The larger the value, the slope of the linear relationship is the density parameter of the film of the light-emitting sublayer 1033.
  • the greater the density parameter of the film the greater the density of the light-emitting sublayer 1033, and the longer the life of the display panel 100.
  • the film density parameter of the light-emitting sublayer 1033 is greater than or equal to the first threshold, the lifespan of the display panel 100 is greatly improved.
  • the film-forming quality of the light-emitting sub-layer 1033 can also be evaluated by measuring the dimensional deformation amplitude of the light-emitting sub-layer 1033.
  • the ratio between the size change range of the light-emitting sub-layer 1033 and the original shape and size is less than or equal to 5%.
  • the dimensional change range of the light-emitting sub-layer 1033 includes but is not limited to the thickness expansion range of the light-emitting sub-layer 1033 .
  • the ratio of its thickness expansion to the original thickness of the light-emitting sublayer 1033 is less than or equal to 5%.
  • the light-emitting sublayer 1033 has a first thickness a before being powered on, and after the display panel 100 is lit at a preset brightness for a preset working time, the light-emitting sublayer 1033 has a second thickness b.
  • the preset brightness may be 100 nits, and the preset time may be 1 hour. Specifically, after the display panel 100 was operated at a brightness of 100 nit for 1 hour, an interferometer was used to measure the thickness before and after lighting.
  • the thickness of the display panel 100 before and after being heated can also be evaluated by heating the display panel 100 .
  • the ratio between its dimensional deformation amplitude and the original shape and size of the light-emitting sub-layer 1033 is less than or equal to 10%.
  • the ratio of its thickness expansion to the original thickness of the light-emitting sub-layer 1033 is less than or equal to 10%.
  • the luminescent sublayer 1033 before heating has a first thickness a
  • the luminescent sublayer has a second thickness c; where the second thickness c and the first thickness
  • the thickness expansion amplitude ⁇ 2 of a is less than or equal to 10%.
  • ⁇ 2 [(c-a)/a]*100%.
  • the preset temperature can be 100 degrees Celsius, and the preset working time can be 1 hour. Specifically, the display panel 100 is heated to 100 degrees Celsius, maintained at 100 degrees Celsius for 1 hour, and the thickness of the heated display panel 100 is measured using an interferometer.
  • Table 2 shows the thickness expansion range of the light-emitting sublayer when the display panel 100 is powered on and heated.
  • the thickness of the luminescent sub-layer 1033 before and after heating is measured by an interferometer, and the thickness expansion amplitude before and after heating is obtained.
  • the smaller the thickness expansion amplitude the better the film-forming quality of the luminescent sub-layer 1033.
  • the luminescent sub-layer The higher the density of the 1033 film, the better the performance of the display panel 100, and the smaller the thickness expansion after heating.
  • the maximum value of ⁇ 1 can be selected as 5%, 4.5%, 4%, 3.5%, 3%, etc.; the maximum value of ⁇ 2 can be selected as 10%, 9.5%, 9%, 8.5 %, 8%, 7.5%, 7%, etc.
  • the film-forming quality of the light-emitting sublayer 1033 of the display panel 100 is evaluated from two dimensions. This includes evaluating the density of the light-emitting sub-layer 1033, and evaluating the display panel 100 as a whole, and evaluating the thickness of the light-emitting sub-layer 1033 of the display panel 100 before and after being heated. Evaluating the film-forming quality of the display panel 100 in two dimensions shows that under the characterization of an atomic force microscope, the greater the slope, the greater the film density parameter of the light-emitting sublayer 1033, and the greater the density of the light-emitting sublayer 1033.
  • the higher the density of the light-emitting sublayer 1033 the more beneficial it is to the light-emitting performance of the blue phosphorescent material.
  • the interferometer is used to measure the thickness of the complete display panel 100 before and after heating to obtain the thickness expansion amplitude of the luminescent sub-layer 1033 before and after heating. The smaller the thickness expansion amplitude of the luminescent sub-layer 1033, the better the film-forming quality of the luminescent sub-layer 1033. , the higher the density of the light-emitting sublayer, the better the light-emitting performance, and the smaller the thickness expansion after heating.
  • FIG. 5 is an energy level arrangement diagram of a display panel provided by an embodiment of the present application.
  • the lowest unoccupied orbital energy level and the highest occupied orbital energy level of the hole transport sublayer 1032, the light emitting sublayer 1033 and the electron transport sublayer 1034 decrease in sequence.
  • the light emitting sublayer 1033 and the electron transport sublayer 1034 decrease in sequence, that is, the energy levels of each adjacent organic film layer material
  • the highest occupied orbital (The Highest Occupied Molecular Orbitals) energy level and the lowest unoccupied orbital (The Lowest Unoccupied Molecular Orbitals) energy level are arranged in a stepped manner. This arrangement is conducive to the balanced injection and transmission of carriers and reduces the energy level barrier. , thereby improving the luminous efficiency of the display panel 100 and obtaining optimal device performance.
  • the highest occupied orbit refers to the molecular orbital with the highest energy among the molecular orbitals occupied by electrons. It is called the highest occupied orbital, also called the highest occupied molecular orbital. Among the molecular orbitals that are not occupied by electrons, the molecular orbital with the lowest energy is called the lowest unoccupied orbital.
  • electrons and holes can be injected in a balanced ratio of 1:1 to achieve efficient utilization of electrons and holes.
  • holes can be effectively injected from the first electrode 102 into the display panel 100.
  • the transport rate of holes is generally greater than the transport rate of electrons.
  • the energy level structures of the hole transport sublayer 1032 and the light-emitting sublayer 1033 are matched, and Match the hole migration velocity.
  • electrons can be efficiently injected from the second electrode 104 into the display panel 100.
  • the lowest unoccupied orbital energy level and the highest occupied orbital energy level of the hole injection sublayer 1031, the hole transport sublayer 1032, the light emitting sublayer 1033, the electron transport sublayer 1034 and the electron injection sublayer 1035 Decrease in turn. Such an arrangement is conducive to the balanced injection and transmission of carriers and reduces the energy level barrier, thereby further improving the luminous efficiency of the display panel 100 and obtaining optimal device performance.
  • the energy level difference between the highest occupied orbitals of the hole transport sublayer 1032 and the light emitting sublayer 1033 is less than or equal to 0.2 eV, and the energy level difference between the lowest unoccupied orbitals of the electron transport sublayer 1034 and the light emitting sublayer 1033 is less than or equal to 0.2 eV.
  • the energy level difference between the highest occupied orbitals of the hole transport sublayer 1032 and the light emitting sublayer 1033 may be any one of 0.05eV, 0.08eV, 0.12eV, 0.15eV, 0.18eV or 0.2eV.
  • the energy level difference between the lowest empty orbitals of the hole transport sublayer 1032 and the light emitting sublayer 1033 may be any one of 0.05eV, 0.08eV, 0.12eV, 0.15eV, 0.18eV or 0.2eV.
  • the display panel 100 further includes a thin film transistor structural layer disposed on the substrate 101 , and the thin film transistor structural layer is used to drive the display panel 100 to emit light.
  • the first electrode 102 is an anode, and the material of the first electrode 102 includes: indium tin oxide material and silver. Specifically, it can be a three-layer stacked structure of indium tin oxide, silver, and indium tin oxide.
  • the second electrode 104 is a cathode, and the material of the second electrode 104 is magnesium-silver alloy.
  • inventions of the present application also provide a method for manufacturing a display panel.
  • the method for manufacturing the display panel 100 includes the following steps:
  • Step B001 Provide a first electrode, wherein the first electrode includes indium tin oxide material and silver.
  • step B002 is also included: sequentially forming a hole injection sub-layer and a hole transport sub-layer on the first electrode, wherein the material of the hole transport sub-layer can be NPB(N,N′-bi(1 -naphthyl)-N,N′-diphenyl-1,1′-biphenyl-4-4′-diamine), with a thickness ranging from 30 nm to 60 nm. In a specific embodiment, the thickness of the hole transport sublayer may be 45 nanometers.
  • Step B003 Form an electron blocking layer on the hole transport sublayer.
  • the material of the electron blocking layer may be TAPC (4,4'-cyclohexylbis[N,N-bis(4-methylphenyl)aniline]).
  • the thickness of the electron blocking layer may range from 2 nanometers to 10 nanometers. In a specific embodiment, the thickness of the electron blocking layer may be 5 nanometers.
  • Step B004 Form a light-emitting sublayer on the electron blocking layer.
  • the light-emitting sublayer is an organic light-emitting material, and the concentration of the doped organic light-emitting material is less than 2%.
  • the evaporation rate of the light-emitting sublayer is less than or equal to 1.5 angstroms/second. In one embodiment, the evaporation rate of the light-emitting sublayer is 1.0 angstroms/second.
  • the host material of the organic light-emitting material can be at least one of DCB, CBP, CDBP, CBPE, mCP, BCzph, CzC, 4CzPBP, TPBi, BCzTPM, BCPPA, NPB, TAPC, and Firpic, wherein the organic light-emitting material
  • the chemical structural formula is shown in Figure 4.
  • the thickness of the luminous character layer can range from 10 nanometers to 30 nanometers. In a specific embodiment, the thickness of the light-emitting sublayer may be 20 nanometers.
  • Step B005 Form an electron transport sublayer and an electron injection sublayer in sequence on the side of the light emitting sublayer away from the first electrode.
  • the material of the electron transport sublayer can be TPBi (1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene), and the thickness of the electron transport sublayer ranges from 20 nanometers to 40 nanometers. nanometer. In a specific embodiment, the thickness of the electron transport sublayer may be 35 nanometers.
  • Step B006 evaporate a second electrode on the side of the electron injection sublayer away from the first electrode.
  • the material of the second electrode may include magnesium-silver alloy.
  • the evaporation rate of the second electrode is less than or equal to 3 angstroms/second. In one embodiment, the evaporation rate of the second electrode may be 2 angstroms/second.
  • the thickness of the second electrode is between 50 nanometers and 150 nanometers. For example, the thickness of the second electrode can be 100 nanometers.

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  • Electroluminescent Light Sources (AREA)

Abstract

一种显示面板（100），显示面板（100）包括衬底（101）、第一电极（102）、发光层（103）和第二电极（104）。其中，第一电极（102）设置在衬底（101）上。发光层（103）设置在第一电极（102）远离衬底（101）的一面。发光层（103）包括发光子层（1033）。发光子层（1033）的薄膜致密性参数大于或等于第一阈值，薄膜致密性参数由单位受力条件下薄膜产生的形变量决定。

Description

显示面板 技术领域
本申请涉及显示技术领域，尤其涉及一种显示面板。
背景技术
有机发光二极管(Organic Light Emitting Diodes，OLED)显示面板具有自发光、快响应、广视角等特点，应用前景非常广阔。
在现有的OLED显示面板的结构设计策略中，更多考虑的是各个功能层的分子轨道能级排列形式，但是，优化能级排列形式更多的是优化OLED器件的效率，然而，效率并不是限制蓝色磷光OLED器件大规模商用的主要原因，是因为现有的蓝色磷光OLED器件的寿命普遍较短，才导致蓝色磷光OLED发光器件得不到广泛应用。
技术问题
本申请实施例提供一种显示面板，用于提高显示面板的使用寿命。
技术解决方案
本申请实施例提供一种显示面板，其包括：
衬底，
第一电极，设置在所述衬底上；
发光层，设置在所述第一电极远离所述衬底的一面，所述发光层包括依次层叠设置的空穴注入子层、空穴传输子层、发光子层、电子传输子层、以及电子注入子层；
第二电极，设置在所述发光层远离所述衬底的一面；
其中，所述发光子层的薄膜致密性参数大于或等于第一阈值，所述薄膜致密性参数由单位受力条件下薄膜产生的形变量决定。
可选的，在本申请提供的一些实施例中，所述薄膜致密性参数由所述薄膜的厚度方向上，所述单位受力条件下，所述薄膜的受力部分产生的厚度形变量决定。
可选的，在本申请提供的一些实施例中，所述薄膜致密性参数可以由如下公式计算得到：
X＝ΔF/ΔH，
其中，ΔF为薄膜的厚度方向上的不同作用力的差值；ΔH为薄膜的受力部分在不同作用力下的厚度差值。
可选的，在本申请提供的一些实施例中，所述第一阈值为-1.7，且所述发光子层的所述薄膜致密性参数小于0。
可选的，在本申请提供的一些实施例中，所述发光子层在所述显示面板通电工作状态下，其尺寸形变幅度与所述发光子层原有形状尺寸之间的比值小于或等于5％。
可选的，在本申请提供的一些实施例中，所述发光子层在所述显示面板通电工作状态下，其厚度膨胀幅度与所述发光子层原有厚度之间的比值小于或等于5％。
可选的，在本申请提供的一些实施例中，所述发光子层在加热状态下，其尺寸形变幅度与所述发光子层原有形状尺寸之间的比值小于或等于10％。
可选的，在本申请提供的一些实施例中，所述发光子层在加热状态下，其厚度膨胀幅度与所述发光子层原有厚度之间的比值小于或等于10％。
可选的，在本申请提供的一些实施例中，所述空穴传输子层、所述发光子层和所述电子传输子层的最高占据轨道的能级依次减小，所述空穴传输子层、所述发光子层和所述电子传输子层的最低空轨道的能级依次减小。
可选的，在本申请提供的一些实施例中，所述空穴传输子层和所述发光子层的最高占据轨道的能级差小于或等于0.2eV，所述电子传输子层和所述发光子层的最低空轨道的能级差小于等于0.2eV。
可选的，在本申请提供的一些实施例中，所述发光子层包括蓝色磷光发光材料或蓝色荧光发光材料。
可选的，在本申请提供的一些实施例中，所述发光子层包括红色磷光发光材料或红色荧光发光材料。
可选的，在本申请提供的一些实施例中，所述发光子层包括绿色磷光发光材料或绿色荧光发光材料。
可选的，在本申请提供的一些实施例中，所述第一电极为阳极，所述第二电极为阴极。
本申请实施例提供一种显示面板，其包括：
衬底，
第一电极，设置在所述衬底上；
发光层，设置在所述第一电极远离所述衬底的一面，所述发光层包括依次层叠设置的空穴注入子层、空穴传输子层、发光子层、电子传输子层、以及电子注入子层；
第二电极，设置在所述发光层远离所述衬底的一面；
其中，所述发光子层的薄膜致密性参数大于或等于第一阈值，所述薄膜致密性参数由单位受力条件下薄膜产生的形变量决定，所述薄膜致密性参数通过原子力显微镜表征。
可选的，在本申请提供的一些实施例中，所述薄膜致密性参数由所述薄膜的厚度方向上，所述单位受力条件下，所述薄膜的受力部分产生的厚度形变量决定。
可选的，在本申请提供的一些实施例中，所述薄膜致密性参数可以由如下公式计算得到：
X＝ΔF/ΔH，
其中，ΔF为薄膜的厚度方向上的不同作用力的差值；ΔH为薄膜的受力部分在不同作用力下的厚度差值。
可选的，在本申请提供的一些实施例中，所述第一阈值为-1.7，且所述发光子层的所述薄膜致密性参数小于0。
可选的，在本申请提供的一些实施例中，所述发光子层在所述显示面板通电工作状态下，其厚度膨胀幅度与所述发光子层原有厚度之间的比值小于或等于5％。
可选的，在本申请提供的一些实施例中，所述发光子层在加热状态下，其厚度膨胀幅度与所述发光子层原有厚度之间的比值小于或等于10％。
有益效果
本申请实施例提供一种显示面板，显示面板包括衬底、第一电极、发光层和第二电极。其中，第一电极设置在衬底上。发光层设置在第一电极远离衬底的一面。发光层包括依次层叠设置在第一电极上的空穴注入子层、空穴传输子层、 发光子层、电子传输子层以及电子注入子层。其中，发光子层的薄膜致密性参数大于或等于第一阈值，薄膜致密性参数由单位受力条件下薄膜产生的形变量决定。本申请的发明人发现，当发光子层的薄膜致密性参数大于或等于第一阈值时，薄膜致密性参数和显示面板的寿命正相关，薄膜致密性参数越大，薄膜致密度越高，显示面板的寿命越长。
附图说明
为了更清楚地说明本申请实施例中的技术方案，下面将对实施例描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本申请的一些实施例，对于本领域技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。
图1为本申请实施例提供的显示面板的一种结构示意图；
图2为本实施例利用原子力显微镜对发光子层的薄膜致密性参数进行表征的示意图；
图3为本申请实施例提供的以mCP为发光子层的主体材料拟合的线性关系；
图4为本申请实施例提供的有机发光材料的化学结构式；
图5为本申请实施例提供的显示面板的一种能级排布方式图。
本发明的实施方式
为了使本申请的目的、技术方案和优点更加清楚，下面将结合附图对本申请作进一步地详细描述，请参照附图中的图式，其中相同的组件符号代表相同的组件，以下的说明是基于所示的本申请具体实施例，其不应被视为限制本申请未在此详述的其他具体实施例。本说明书所使用的词语“实施例”意指实例、示例或例证。
在本申请的描述中，需要理解的是，术语“中心”、“纵向”、“横向”、“长度”、“宽度”、“厚度”、“上”、“下”、“前”、“后”、“左”、“右”、“竖直”、“水平”、“顶”、“底”、“内”、“外”、“顺时针”、“逆时针”等指示的方位或位置关系为基于附图所示的方位或位置关系，仅是为了便于描述本申请和简化描述，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申请的限制。此外，术语“第一”、“第二”仅用于描述目的，而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此， 限定有“第一”、“第二”的特征可以明示或者隐含地包括一个或者更多个所述特征。在本申请的描述中，“多个”的含义是两个或两个以上，除非另有明确具体的限定。
本申请实施例提供一种显示面板。以下分别进行详细说明。需说明的是，以下实施例的描述顺序不作为对实施例优选顺序的限定。
下面通过具体实施例对本申请提供的显示面板进行详细的阐述。
请参考图1，图1为本申请实施例提供显示面板的一种结构示意图。本申请实施例提供一种显示面板，显示面板100包括衬底101、第一电极102、发光层103和第二电极104。其中，第一电极102设置在衬底101上。发光层103设置在第一电极102远离衬底101的一面。发光层103包括依次层叠设置在第一电极102上的空穴注入子层1031、空穴传输子层1032、发光子层1033、电子传输子层1034以及电子注入子层1035。其中，发光子层1033的薄膜致密性参数大于或等于第一阈值，薄膜致密性参数由单位受力条件下薄膜产生的形变量决定。
本申请的发明人发现，当发光子层1033的薄膜致密性参数大于或等于第一阈值时，薄膜致密性参数和显示面板100的寿命正相关，薄膜致密性参数越大，薄膜致密度越高，显示面板100的寿命越长。
应该理解的是，在本申请实施例中，薄膜致密性参数和薄膜致密度有关，薄膜致密度越高，则薄膜致密性参数越大，显示面板100的寿命越长。
需要说明的是，在本申请实施例中，单位受力包括但不限于对发光子层1033施加的作用力，这里的单位受力是指对发光子层1033施加计量用的最小单元的作用力，例如1N、2N、5N、10N等。
需要说明的是，在本申请实施例中，薄膜产生的形变量包括但不限于薄膜的厚度的形变量。
在一些实施例中，薄膜致密性参数由薄膜的厚度方向上，单位受力条件下，薄膜的受力部分产生的厚度形变量决定。具体的，薄膜致密性参数可以由如下公式计算得到：X＝ΔF/ΔH，其中，X为薄膜致密性参数，ΔF为薄膜的厚度方向上的不同作用力的差值；ΔH为薄膜的受力部分在不同作用力下的厚度差值，0＞X≥-1.7N/cm。
也就是说，第一阈值为-1.7，当薄膜致密性参数大于等于-1.7，且小于0时，薄膜致密性参数越大，则薄膜的致密度越高，显示面板100的寿命越长。
其中，ΔF可以为对同一受力部分施加两个不同的作用力的差值，ΔH为对应于两个不同作用力所对应的厚度的差值。或者，ΔF为对两个不同的受力部分施加的作用力的差值，ΔH为对应于两个不同作用力所对应的厚度的差值。
需要说明的是，在本申请实施例中，薄膜的单位受力越大，则对应的薄膜的厚度越小。
在本申请中，可以利用原子力显微镜对发光子层1033的薄膜致密性参数进行表征。在原子力显微镜的表征下，发光子层1033的厚度与发光子层1033受到的原子力显微镜的探针的作用力之间呈线性关系，线性关系的斜率即为薄膜致密性参数。
具体的，利用原子力显微镜对发光子层1033进行表征，然后，建立发光子层1033的厚度与发光子层1033受到的原子力显微镜的探针的作用力之间的线性关系，线性关系的斜率越大，则发光子层1033的薄膜的致密度越大，则显示面板100的寿命越长。
请参考图2，图2为本实施例利用原子力显微镜对发光子层的薄膜致密性参数进行表征的示意图。对发光子层1033的薄膜致密性参数进行评价具体包括利用原子力显微镜表征的发光子层1033。
原子力显微镜表征发光子层1033的过程可以包括在基底S上设置发光子层1033，然后，利用探针P对发光子层1033的相对厚度进行检测。其中，在基底S上设置发光子层1033包括在基底S上设置聚酰亚胺层PI，聚酰亚胺层PI覆盖基底S的一部分。随后，在基底S上蒸镀发光子层1033，发光子层1033覆盖聚酰亚胺层PI和基底S，然后再将聚酰亚胺层PI撕除，以此在基底S上制得发光子层1033。在本申请实施例中，发光子层1033仅覆盖基底S的一部分，以此形成高度差，用于测量发光子层1033的相对厚度。利用探针P对发光子层1033的相对厚度进行检测的步骤包括：首先，随机选取发光子层1033上的任意一点，探针P对其施加第一作用力，然后利用第一作用力探针P施加至基底S上，测得发光子层1033的第一相对厚度。随后，随机选取发光子层1033上的另一点，探针P对其施加第二作用力，然后利用第二作用力探针P施加至 基底S上，测得发光子层1033的第二相对厚度。以此反复，利用第三作用力测得发光子层1033的第三相对厚度，利用第四作用力测得发光层的第四相对厚度。利用第N作用力测得发光子层1033的第N相对厚度。最后，以发光子层1033受到的探针的作用力为横坐标，以发光子层1033的厚度为纵坐标，所拟合的线性关系的斜率作为发光子层1033的薄膜的致密性参数。斜率越大则发光子层1033的薄膜致密度越大，则显示面板100的寿命越长。
在本申请实施例中，发光子层1033的厚度随着发光子层1033受到的探针P的作用力的增大而减小。发光子层1033受到的探针P的作用力越大，则对应的发光子层1033的厚度越小，本申请实施例以发光子层1033受到的探针P的作用力为横坐标，以发光子层1033的厚度为纵坐标，拟合得到对应的线性关系。
请参考图3，图3为本申请实施例提供的以mCP(N,N-二咔唑基-3,5-苯)为发光子层的发光主体材料拟合的线性关系。在本申请实施例中，以发光子层1033受到的探针的作用力(F)为横坐标，以发光子层1033的厚度(T)为纵坐标，所拟合的线性关系的斜率作为发光子层1033的薄膜致密性参数，其中，斜率为-1.69。
具体的，本申请实施例利用10种不同的有机发光材料作为发光子层1033的主体材料，以此评价发光子层1033的成膜致密度以及发光性能。请参考图4，图4为本申请实施例提供的有机发光材料的化学结构式。有机发光材料包括DCB、CBP、CDBP、CBPE、mCP、BCzph、CzC、4CzPBP、TPBi、BCzTPM、BCPPA、NPB、TAPC和Firpic。
请参阅表一，表一为10种不同的有机发光材料作为发光子层的主体材料的薄膜致密性参数及显示面板的性能测试结果。
表一：
Figure PCTCN2022094905-appb-000001
Figure PCTCN2022094905-appb-000002
由表一可知，在相同的条件下利用不同的有机发光材料作为主体材料制得的发光子层1033及显示面板100，在原子力显微镜的表征下，斜率越大，则发光子层1033的薄膜致密度越大。随着发光子层1033的薄膜致密度的升高，对电压和电致发光峰位(EL Peak)的影响较小，外量子效率(EQE)有微弱的提升，寿命提升幅度非常显著。证明发光子层1033的薄膜致密度越高，对蓝色磷光材料的发光性能越有益。
需要说明的是，斜率为利用上述的原子力显微镜作用于发光子层1033的薄膜所测得的。
当斜率大于等于-1.7时，显示面板100的寿命提升幅度非常显著，当然，第一阈值也可以选择-1.65、-1.6、-1.55、-1.5、-1.45、-1.4、-1.35、-1.3、-1.25、-1.2、-1.15等。
相较于红色磷光与绿色磷光材料，蓝色磷光材料的寿命特别短，导致显示面板100整体寿命与可靠性降低。在本申请实施例中，以蓝色磷光材料为例，通过提高蓝色磷光材料的成膜的致密度，从而提高蓝色磷光材料的显示面板100的寿命及可靠性，从而提高市场竞争力。
在一些实施例中，发光子层1033包括但不限于蓝色磷光发光材料或蓝色荧光发光材料。发光子层1033还可以是红色磷光发光材料和绿色磷光发光材料， 红色荧光发光材料和绿色荧光发光材料。
在本申请实施例中，利用原子力显微镜对发光子层1033进行表征，建立发光子层1033的厚度与发光子层1033受到的原子力显微镜的探针的作用力之间的线性关系，线性关系的斜率越大，线性关系的斜率为发光子层1033的薄膜的致密性参数，薄膜的致密性参数越大，则发光子层1033的致密度越大，则显示面板100的寿命越长。在本申请实施例中，当发光子层1033的薄膜致密性参数大于等于第一阈值时，显示面板100的寿命大幅度提高。
在本申请的一些实施例中，还可以通过对发光子层1033的尺寸形变幅度评价发光子层1033的成膜质量。
为了进一步评价发光子层1033的成膜质量，发光子层1033在显示面板100通电工作状态下，发光子层1033的尺寸变化幅度与原有的形状尺寸之间的比值小于或等于5％。
需要说明的是，发光子层1033的尺寸变化幅度包括但不限于发光子层1033的厚度膨胀幅度。
在一些实施例中，发光子层1033在显示面板100通电工作状态下，其厚度膨胀幅度与发光子层1033原有厚度之间的比值小于或等于5％。
例如，发光子层1033通电工作前具有第一厚度a，显示面板100在预设亮度下点亮预设工作时间后，发光子层1033具有第二厚度b。第二厚度b和第一厚度a的厚度膨胀幅度ω1小于等于5％，其中，ω1＝[(b-a)/a]*100％。
在一些实施例中，预设亮度可以是100nit(尼特)，预设时间可以是1小时。具体的，显示面板100在100nit的亮度下工作1小时后，利用干涉仪对发亮前后的厚度进行测量。
在一些实施例中，还可以通过加热显示面板100的方式对显示面板100受热前后的厚度进行评价。
其中，发光子层1033在加热状态下，其尺寸形变幅度与发光子层1033原有形状尺寸之间的比值小于或等于10％。
在一些实施例中，发光子层1033在加热状态下，其厚度膨胀幅度与发光子层1033原有厚度之间的比值小于或等于10％。
具体的，加热前的发光子层1033具有第一厚度a，显示面板100在预设温 度下加热预设工作时间后，发光子层具有第二厚度c；其中，第二厚度c和第一厚度a的厚度膨胀幅度ω2小于等于10％。其中，ω2＝[(c-a)/a]*100％。
预设温度可以是100摄氏度，预设工作时间可以是1小时。具体的，将显示面板100加热至100摄氏度，在100摄氏度下保持1小时，利用干涉仪对加热后的显示面板100的厚度进行测量。
请参考表二，表二为显示面板100通电状态下和加热状态下发光子层的厚度膨胀幅度。
表二：
有机发光材料 ω1 ω2
DCB 7.4％ 14.5％
CBP 7.0％ 13.7％
CDBP 6.5％ 12.4％
CBPE 5.7％ 11.5％
mCP 5.1％ 10.4％
BCzPh 4.6％ 10.1％
CzC 4.1％ 9.2％
4CzPBP 3.9％ 8.7％
BCzTPM 3.6％ 7.9％
BCPPA 3.2％ 7.2％
由表二可知，通过干涉仪对发光子层1033受热前后的厚度进行测量，求得受热前后的厚度膨胀幅度，厚度膨胀幅度越小，说明发光子层1033的成膜质量越好，发光子层1033的薄膜致密度越高，显示面板100的性能越好的器件，受热后的厚度膨胀幅度越小。需要说明的是，在实际应用中，ω1的最大值可以选取为5％、4.5％、4％、3.5％、3％等；ω2的最大值可以选取为10％、9.5％、9％、8.5％、8％、7.5％、7％等。
结合表一和表二可知，发光子层的薄膜致密性参数越高，薄膜致密度越高，发光性能越好，受热后的厚度膨胀幅度越小，显示面板100的寿命越长。
在本申请实施例中，从两个维度对显示面板100的发光子层1033的成膜质量进行评价。包括对发光子层1033的密度进行评价，以及将显示面板100作为整体，对显示面板100的发光子层1033受热前后的厚度进行评价。通过两个维度对显示面板100的成膜质量进行评价，表明在原子力显微镜的表征下，斜率越大，发光子层1033的薄膜致密性参数越大，则发光子层1033的密度越大。随着发光子层1033密度的升高，对电压和电致发光峰位(EL Peak)的影响较 小，外量子效率(EQE)有微弱的提升，寿命提升幅度非常显著。证明发光子层1033密度越高，对蓝色磷光材料的发光性能越有益。通过干涉仪对完整的显示面板100受热前后的厚度进行测量，求得发光子层1033受热前后的厚度膨胀幅度，发光子层1033厚度膨胀幅度越小，说明发光子层1033的成膜质量越好，发光子层密度越高，发光性能越好，受热后的厚度膨胀幅度越小。
请参考图5，图5为本申请实施例提供的显示面板的一种能级排布方式图。在一些实施例中，空穴传输子层1032、发光子层1033和电子传输子层1034的最低空轨道能级和最高占据轨道能级依次减小。
在本申请实施例中，由于空穴传输子层1032、发光子层1033和电子传输子层1034的最低空轨道能级和最高占据轨道能级依次减小，即各个相邻有机膜层材料的最高占据轨道(The Highest Occupied Molecular Orbitals)能级和最低空轨道(The Lowest Unoccupied Molecular Orbitals)能级呈阶梯式排列，这样的排列方式有利于载流子的平衡注入和传输，降低能级势垒，从而提高显示面板100的发光效率，进而获得最优的器件性能。
需要说明的是，最高占据轨道指的是在电子占有的分子轨道中，能量最高的分子轨道叫做最高占据轨道，也叫最高占有分子轨道。在未被电子占据的分子轨道中，能量最低的分子轨道称为最低空轨道。
在一些实施例中，电子、空穴能够以1:1的比例平衡注入，实现电子空穴的高效利用。
其中，为了降低从第一电极102注入空穴的势垒，使空穴能从第一电极102有效地注入到显示面板100中。空穴的传输速率一般是大于电子的传输速率，为了让从电极注入的电子和空穴的复合发生在发光子层1033中，空穴传输子层1032及发光子层1033能级结构匹配，且匹配空穴迁移速度。为了降低从第二电极104注入电子的势垒，使电子能从第二电极104有效地注入到显示面板100中。因此，在选择电子注入子层1035材料的时候，为了使电子能从第二电极104有效地注入到显示面板100中。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OLED器件中。因此，在选择电子注入层材料的时候，需要考虑材料能级和第二电极104材料的匹配。
在一些实施例中，空穴注入子层1031、所述空穴传输子层1032、发光子层 1033、电子传输子层1034和电子注入子层1035的最低空轨道能级和最高占据轨道能级依次减小。这样的排列方式有利于载流子的平衡注入和传输，降低能级势垒，从而进一步提高显示面板100的发光效率，进而获得最优的器件性能。
在一些实施例中，空穴传输子层1032和发光子层1033的最高占据轨道的能级差小于或等于0.2eV，电子传输子层1034和发光子层1033的最低空轨道的能级差小于等于0.2eV。从而减小相邻的有机膜层间的势垒，进一步提高显示面板100的发光效率。
具体的，空穴传输子层1032和发光子层1033的最高占据轨道的能级差可以是0.05eV、0.08eV、0.12eV、0.15eV、0.18eV或0.2eV中的任意一者。空穴传输子层1032和发光子层1033的最低空轨道的能级差可以是0.05eV、0.08eV、0.12eV、0.15eV、0.18eV或0.2eV中的任意一者。从而减小相邻的有机膜层间的势垒，进一步提高显示面板100的发光效率。
在一些实施例中，显示面板100还包括薄膜晶体管结构层，薄膜晶体管结构层设置在衬底101上，薄膜晶体管结构层用于驱动显示面板100发光。
在一些实施例中，第一电极102为阳极，第一电极102的材料包括：氧化铟锡材料和银，具体可以为氧化铟锡、银、氧化铟锡三层叠层结构。第二电极104为阴极，第二电极104的材料为镁银合金。
相应的，本申请实施例还提供一种显示面板的制作方法，显示面板100的制作方法包括以下步骤：
步骤B001：提供第一电极，其中，第一电极包括氧化铟锡材料和银。
在步骤B001之后，还包括步骤B002：在第一电极上依次形成空穴注入子层和空穴传输子层，其中，空穴传输子层的材料可以是NPB(N,N′-二(1-萘基)-N,N′-二苯基-1,1′-联苯-4-4′-二胺)，其厚度介于30纳米至60纳米。在一具体的实施例中，空穴传输子层的厚度可以是45纳米。
步骤B003：在空穴传输子层上形成电子阻挡层，电子阻挡层的材料可以是TAPC(4,4'-环己基二[N,N-二(4-甲基苯基)苯胺])。电子阻挡层的厚度为可以介于2纳米至10纳米。在一具体的实施例中，电子阻挡层的厚度可以是5纳米。
步骤B004：在电子阻挡层上形成发光子层，发光子层为有机发光材料，其掺杂的有机发光材料的浓度小于2％。发光子层的蒸镀速率小于等于1.5埃/秒。 在一实施例中，发光子层的蒸镀速率为1.0埃/秒。其中，有机发光材料的主体材料可以是DCB、CBP、CDBP、CBPE、mCP、BCzph、CzC、4CzPBP、TPBi、BCzTPM、BCPPA、NPB、TAPC、和Firpic中的至少一种，其中，有机发光材料的化学结构式如图4所示。发光字层的厚度可以介于10纳米至30纳米。在一具体的实施例中，发光子层的厚度可以是20纳米。
步骤B005：在发光子层远离第一电极的一面依次形成电子传输子层和电子注入子层。其中，电子传输子层的材料可以是TPBi(1,3,5-三(1-苯基-1H-苯并咪唑-2-基)苯)，电子传输子层的厚度介于20纳米至40纳米。在一具体的实施例中，电子传输子层的厚度可以是35纳米。
步骤B006：在电子注入子层远离第一电极的一面蒸镀第二电极。其中，第二电极的材料可以包括镁银合金。第二电极的蒸镀速率小于或等于3埃/秒，在一实施例中，第二电极的蒸镀速率可以是2埃/秒。第二电极的厚度介于50纳米至150纳米，例如，第二电极的厚度可以是100纳米。
综上所述，虽然本申请已以优选实施例揭露如上，但上述优选实施例并非用以限制本申请，本领域的普通技术人员，在不脱离本申请的精神和范围内，均可作各种更动与润饰，因此本申请的保护范围以权利要求界定的范围为准。

Claims (20)

  1. 一种显示面板，其包括：
    衬底，
    第一电极，设置在所述衬底上；
    发光层，设置在所述第一电极远离所述衬底的一面，所述发光层包括依次层叠设置的空穴注入子层、空穴传输子层、发光子层、电子传输子层、以及电子注入子层；
    第二电极，设置在所述发光层远离所述衬底的一面；
    其中，所述发光子层的薄膜致密性参数大于或等于第一阈值，所述薄膜致密性参数由单位受力条件下薄膜产生的形变量决定。
  2. 根据权利要求1所述的显示面板，其中，所述薄膜致密性参数由所述薄膜的厚度方向上，所述单位受力条件下，所述薄膜的受力部分产生的厚度形变量决定。
  3. 根据权利要求2所述的显示面板，其中，所述薄膜致密性参数可以由如下公式计算得到：
    X＝ΔF/ΔH，
    其中，ΔF为薄膜的厚度方向上的不同作用力的差值；ΔH为薄膜的受力部分在不同作用力下的厚度差值。
  4. 根据权利要求3所述的显示面板，其中，所述第一阈值为-1.7，且所述发光子层的所述薄膜致密性参数小于0。
  5. 根据权利要求1所述的显示面板，其中，所述发光子层在所述显示面板通电工作状态下，其尺寸形变幅度与所述发光子层原有形状尺寸之间的比值小于或等于5％。
  6. 根据权利要求5所述的显示面板，其中，所述发光子层在所述显示面板通电工作状态下，其厚度膨胀幅度与所述发光子层原有厚度之间的比值小于或等于5％。
  7. 根据权利要求1所述的显示面板，其中，所述发光子层在加热状态下，其尺寸形变幅度与所述发光子层原有形状尺寸之间的比值小于或等于10％。
  8. 根据权利要求7所述的显示面板，其中，所述发光子层在加热状态下， 其厚度膨胀幅度与所述发光子层原有厚度之间的比值小于或等于10％。
  9. 根据权利要求1所述的显示面板，其中，所述空穴传输子层、所述发光子层和所述电子传输子层的最高占据轨道的能级依次减小，所述空穴传输子层、所述发光子层和所述电子传输子层的最低空轨道的能级依次减小。
  10. 根据权利要求9所述的显示面板，其中，所述空穴传输子层和所述发光子层的最高占据轨道的能级差小于或等于0.2eV，所述电子传输子层和所述发光子层的最低空轨道的能级差小于等于0.2eV。
  11. 根据权利要求1所述的显示面板，其中，所述发光子层包括蓝色磷光发光材料或蓝色荧光发光材料。
  12. 根据权利要求1所述的显示面板，其中，所述发光子层包括红色磷光发光材料或红色荧光发光材料。
  13. 根据权利要求1所述的显示面板，其中，所述发光子层包括绿色磷光发光材料或绿色荧光发光材料。
  14. 根据权利要求1所述的显示面板，其中，所述第一电极为阳极，所述第二电极为阴极。
  15. 一种显示面板，其包括：
    衬底，
    第一电极，设置在所述衬底上；
    发光层，设置在所述第一电极远离所述衬底的一面，所述发光层包括依次层叠设置的空穴注入子层、空穴传输子层、发光子层、电子传输子层、以及电子注入子层；
    第二电极，设置在所述发光层远离所述衬底的一面；
    其中，所述发光子层的薄膜致密性参数大于或等于第一阈值，所述薄膜致密性参数由单位受力条件下薄膜产生的形变量决定，所述薄膜致密性参数通过原子力显微镜表征。
  16. 根据权利要求15所述的显示面板，其中，所述薄膜致密性参数由所述薄膜的厚度方向上，所述单位受力条件下，所述薄膜的受力部分产生的厚度形变量决定。
  17. 根据权利要求16所述的显示面板，其中，所述薄膜致密性参数可以由 如下公式计算得到：
    X＝ΔF/ΔH，
    其中，ΔF为薄膜的厚度方向上的不同作用力的差值；ΔH为薄膜的受力部分在不同作用力下的厚度差值。
  18. 根据权利要求17所述的显示面板，其中，所述第一阈值为-1.7，且所述发光子层的所述薄膜致密性参数小于0。
  19. 根据权利要求15所述的显示面板，其中，所述发光子层在所述显示面板通电工作状态下，其厚度膨胀幅度与所述发光子层原有厚度之间的比值小于或等于5％。
  20. 根据权利要求15所述的显示面板，其中，所述发光子层在加热状态下，其厚度膨胀幅度与所述发光子层原有厚度之间的比值小于或等于10％。
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001006878A (ja) * 1999-06-22 2001-01-12 Matsushita Electric Ind Co Ltd 薄膜ｅｌ素子およびその駆動方法
CN102024909A (zh) * 2010-09-27 2011-04-20 电子科技大学 一种发光稳定的有机电致发光器件及其制备方法
CN106856225A (zh) * 2016-12-15 2017-06-16 上海天马有机发光显示技术有限公司 一种有机发光显示面板及装置
CN112599687A (zh) * 2020-12-10 2021-04-02 北京维信诺科技有限公司 一种发光器件及显示装置
CN113594379A (zh) * 2020-07-27 2021-11-02 广东聚华印刷显示技术有限公司 电致发光器件及其制作方法和发光装置

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011097259A1 (en) * 2010-02-05 2011-08-11 Nitto Denko Corporation Organic light-emitting diode with enhanced efficiency
CN104025332A (zh) * 2011-11-28 2014-09-03 海洋王照明科技股份有限公司 掺杂有机电致发光器件及其制备方法
KR102721689B1 (ko) * 2018-11-09 2024-10-28 삼성디스플레이 주식회사 유기 전계 발광 소자

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001006878A (ja) * 1999-06-22 2001-01-12 Matsushita Electric Ind Co Ltd 薄膜ｅｌ素子およびその駆動方法
CN102024909A (zh) * 2010-09-27 2011-04-20 电子科技大学 一种发光稳定的有机电致发光器件及其制备方法
CN106856225A (zh) * 2016-12-15 2017-06-16 上海天马有机发光显示技术有限公司 一种有机发光显示面板及装置
CN113594379A (zh) * 2020-07-27 2021-11-02 广东聚华印刷显示技术有限公司 电致发光器件及其制作方法和发光装置
CN112599687A (zh) * 2020-12-10 2021-04-02 北京维信诺科技有限公司 一种发光器件及显示装置

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