CN111952477A - Display panel and display device - Google Patents
Display panel and display device Download PDFInfo
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- CN111952477A CN111952477A CN202010856356.0A CN202010856356A CN111952477A CN 111952477 A CN111952477 A CN 111952477A CN 202010856356 A CN202010856356 A CN 202010856356A CN 111952477 A CN111952477 A CN 111952477A
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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]
- H10K50/18—Carrier blocking layers
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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
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- 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
- H10K59/30—Devices specially adapted for multicolour light emission
- H10K59/35—Devices specially adapted for multicolour light emission comprising red-green-blue [RGB] subpixels
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
- H10K85/60—Organic compounds having low molecular weight
- H10K85/615—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene
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- H—ELECTRICITY
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- 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
Abstract
The invention discloses a display panel and a display device. The display panel provided by the embodiment of the invention comprises a substrate and a plurality of light-emitting units, wherein the plurality of light-emitting units are arranged on the substrate; each light-emitting unit comprises an anode, an electron blocking layer, a light-emitting layer and a cathode which are arranged in a stacked mode, the electron blocking layer of at least part of the light-emitting units comprises a first host material and at least one first guest material, the first host material comprises a compound with a planar molecular structure, the at least one first guest material comprises a compound with a non-planar molecular structure, and the hole transport capacity of the electron blocking layer in the direction perpendicular to the light-emitting layer is larger than or equal to that in the direction parallel to the light-emitting layer. According to the display panel provided by the embodiment of the invention, the transverse current transmission can be reduced, so that the color cast caused by color crosstalk is improved.
Description
Technical Field
The invention relates to the field of display, in particular to a display panel and a display device.
Background
An Organic Light Emitting Diode (OLED) display panel is a self-luminous display panel, and the OLED display panel is increasingly applied to various high-performance display fields due to its advantages of lightness, thinness, high brightness, low power consumption, wide viewing angle, high response speed, and wide temperature range.
In the conventional OLED display panel, the lighting voltages of the sub-pixels of the respective colors are not uniform. Specifically, the lighting voltage of the blue sub-pixel is greater than the lighting voltages of the other color sub-pixels. When the blue sub-pixel is lighted, although the voltage is mainly spanned on the blue sub-pixel, part of the voltage is applied to the other color sub-pixels through the common layer to cause the other color sub-pixels to emit light, thereby causing color crosstalk and causing the color cast of the OLED display panel.
Disclosure of Invention
The invention provides a display panel and a display device, which can reduce transverse current transmission to improve color cast caused by color crosstalk.
In a first aspect, an embodiment of the present invention provides a display panel, including a substrate and a plurality of light emitting units disposed on the substrate; each light-emitting unit comprises an anode, an electron blocking layer, a light-emitting layer and a cathode which are arranged in a stacked mode, the electron blocking layer of at least part of the light-emitting units comprises a first host material and at least one first guest material, the first host material comprises a compound with a planar molecular structure, the at least one first guest material comprises a compound with a non-planar molecular structure, and the hole transport capacity of the electron blocking layer in the direction perpendicular to the light-emitting layer is larger than or equal to that in the direction parallel to the light-emitting layer.
According to an aspect of the embodiments of the present invention, the electron blocking layer is formed by co-evaporation or pre-mix evaporation of mainly the first host material and at least one first guest material, and the electron blocking layer has isotropic thin film characteristics.
According to an aspect of an embodiment of the present invention, the first host material and the first guest material each include an aromatic ring compound.
According to an aspect of an embodiment of the present invention, the aromatic rings in the planar molecular structure in the first host material are in the same plane.
According to an aspect of an embodiment of the present invention, the first host material includes any one of a acene derivative, an anthracene derivative, and a triarylamine derivative.
According to an aspect of an embodiment of the invention, the aromatic rings in the non-planar molecular structure of the first guest material are spatially angularly distributed.
According to an aspect of an embodiment of the present invention, the first guest material includes one or more of a carbazole derivative, a fluorene derivative.
According to an aspect of an embodiment of the present invention, the weight proportion of the at least one first guest material in the electron blocking layer is 1% to 50%.
According to an aspect of an embodiment of the present invention, the hole transport ability of the first host material is greater than the hole transport ability of the first guest material.
The first guest material blocks the transport of holes in a direction perpendicular to the light emitting layer more than the first host material blocks the transport of holes in a direction perpendicular to the light emitting layer.
According to an aspect of the embodiments of the present invention, the light emitting unit further includes a hole transport layer between the anode and the electron blocking layer.
According to an aspect of the embodiments of the present invention, the light emitting unit further includes an electron transport layer between the cathode and the light emitting layer.
According to an aspect of an embodiment of the present invention, the plurality of light emitting units includes a red light emitting unit, a green light emitting unit, and a blue light emitting unit.
According to an aspect of an embodiment of the present invention, a red light emitting unit and/or a green light emitting unit includes an electron blocking layer and a hole transporting layer, the electron blocking layer of the red light emitting unit and/or the green light emitting unit includes a first host material, and a HOMO level of the hole transporting layer is greater than a HOMO level of the first host material;
according to an aspect of an embodiment of the present invention, the HOMO level of the hole transport layer is 0.1eV to 0.5eV greater than the HOMO level of the first host material.
In a second aspect, an embodiment of the present invention provides a display device, including the display panel according to any one of the embodiments.
According to the display panel provided by the embodiment of the invention, the display panel comprises a substrate and a plurality of light-emitting units, wherein the electron blocking layer of at least part of the light-emitting units comprises a first host material and at least one first guest material, the first host material comprises a compound with a planar molecular structure, the at least one first guest material comprises a compound with a non-planar molecular structure, the hole transport capability of the electron blocking layer along the direction vertical to the light-emitting layer is larger than or equal to the hole transport capability along the direction parallel to the light-emitting layer, the transport of transverse current (holes) can be reduced, and the current (holes) flowing from the blue light-emitting unit to the light-emitting units of other colors through the common layer can be reduced when the blue light-emitting unit is independently turned on, so that the color crosstalk caused by the improper light emission of the light-emitting units of other colors can be. Moreover, according to the display panel provided by the embodiment of the invention, the hole transmission capability of the electron blocking layer along the direction vertical to the light emitting layer can be improved, and the current efficiency of the light emitting unit is further improved.
Drawings
Other features, objects and advantages of the invention will become apparent from the following detailed description of non-limiting embodiments thereof, when read in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof, and which are not to scale.
Fig. 1 illustrates a schematic cross-sectional structure of a display panel according to an embodiment of the present invention;
fig. 2 illustrates a schematic cross-sectional structure of a display panel according to another embodiment of the present invention;
FIG. 3 shows a schematic stacking of a first host material according to an embodiment of the invention;
fig. 4 shows a schematic stack of a first host material and a first guest material according to an embodiment of the present invention;
FIG. 5 shows an enlarged schematic view of one embodiment of zone M in FIG. 2.
In the figure:
100-a substrate;
200-a light emitting unit; 201-blue light emitting unit; 202-red light emitting unit; 203-green light emitting unit; 210-an anode; 220-an electron blocking layer; 230-a light emitting layer; 240-cathode; 250-a hole transport layer; 260-electron transport layer;
300-pixel definition layer.
Detailed Description
Features and exemplary embodiments of various aspects of the present invention will be described in detail below, and in order to make objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention. It will be apparent to one skilled in the art that the present invention may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
It will be understood that when a layer, region or layer is referred to as being "on" or "over" another layer, region or layer in describing the structure of the component, it can be directly on the other layer, region or layer or intervening layers or regions may also be present. Also, if the component is turned over, one layer or region may be "under" or "beneath" another layer or region.
In the OLED display panel, a common (common) layer is disposed in the blue, green and red sub-pixels to communicate the blue, green and red sub-pixels, and the common layer has a good conductivity, so that current can easily flow through the common layer to other sub-pixels, which causes the other sub-pixels to emit light and causes color shift of the display panel.
Moreover, the wavelengths of the red light, the green light and the blue light are gradually shorter, and the energy is gradually higher, so that the turn-on voltages of the red sub-pixel, the green sub-pixel and the blue sub-pixel are sequentially increased. The turn-on voltage of the blue sub-pixel is larger than the turn-on voltage of the green sub-pixel and/or the red sub-pixel, when the blue sub-pixel is turned on, although the voltage mainly spans the blue sub-pixel, because of the existence of the common layer, partial voltage is applied to the green sub-pixel and/or the red sub-pixel through the common layer, and because the turn-on voltages of the red sub-pixel and the green sub-pixel are smaller than the turn-on voltage of the blue sub-pixel, the red sub-pixel and/or the green sub-pixel are easy to be turned on. In particular, the OLED display panel has a small current in a low gray scale display state, and a Thin Film Transistor (TFT) is not easy to control, and when the blue sub-pixel is independently turned on, the current of the blue sub-pixel in the OLED display panel flows into an adjacent green sub-pixel or red sub-pixel through a transverse common layer, so that the green sub-pixel or the red sub-pixel emits light. Therefore, in the low gray scale display state, red or green crosstalk occurs in the blue picture, which causes a color cast problem of the display panel in the low gray scale display state.
In addition, the lifetime variation trends of the blue sub-pixel, the green sub-pixel and the red sub-pixel in the OLED display panel are inconsistent. For example, the blue sub-pixel attenuates fast, and the red sub-pixel attenuates slowly or even negatively, so that the difference between the lighting voltages of the blue sub-pixel and the red sub-pixel is further increased with the use of the OLED display panel, and particularly, in the low gray scale display state, the change rule of the current efficiency of each sub-pixel is inconsistent in the use process, which easily causes the color shift problem in the low gray scale display state.
In the OLED display panel, the electron blocking layer is adopted to block or slow down the continuous transmission of electrons towards the anode, so that the leakage current of electrons is reduced, and the hole functional material can be protected from being damaged. However, the material of the conventional electron blocking layer has a hole transport capability in a transverse direction (i.e., a direction parallel to the film layer) that is greater than a hole transport capability in a longitudinal direction (i.e., a direction perpendicular to the film layer), which easily causes the transverse transport of holes, causing color crosstalk of the OLED display panel.
Referring to fig. 1 and 2, fig. 1 is a schematic cross-sectional view illustrating a display panel according to an embodiment of the invention, and fig. 2 is a schematic cross-sectional view illustrating a display panel according to another embodiment of the invention.
An embodiment of the present invention provides a display panel, as shown in fig. 1, including: a substrate 100 and a plurality of light emitting cells 200.
The substrate 100 may include one or more layers. The substrate 100 may include an insulating material layer. The substrate 100 may include a flexible organic material layer, for example, a polymer material such as Polyimide (PI), Polycarbonate (PC), Polyethersulfone (PES), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), Polyarylate (PAR), or glass Fiber Reinforced Plastic (FRP). The substrate 100 may further include an inorganic material layer, such as a silicon oxide layer, a silicon nitride layer. The substrate 100 may be transparent, translucent, or opaque.
The substrate 100 may also be an array substrate, the array substrate may include a driving circuit for driving the light emitting cells to emit light, and the driving circuit may be any one of a 2T1C circuit, a 7T1C circuit, a 7T2C circuit, or a 9T1C circuit. Herein, the "2T 1C circuit" refers to a pixel circuit including 2 thin film transistors (T) and 1 capacitor (C) in the pixel circuit, and the other "7T 1C circuit", "7T 2C circuit", "9T 1C circuit", and the like are analogized.
In some optional embodiments, as shown in fig. 2, the display panel may further include a pixel defining layer 300, and the pixel defining layer 300 has a pixel opening. The pixel defining layer 300 may be disposed on the substrate 100. The pixel defining layer 300 may be formed of an organic material such as Polyimide (PI), polyamide, benzocyclobutene (BCB), acryl resin, or phenol resin.
A plurality of light emitting cells 200 are disposed on the substrate 100. Alternatively, each light emitting unit 200 may be located within the pixel opening. The light emitting unit 200 may include a blue light emitting unit 201, a red light emitting unit 202, and a green light emitting unit 203. The blue light emitting unit 201 may correspond to a blue subpixel of the display panel and emit blue light. The red light emitting unit 202 may correspond to a red sub-pixel of the display panel and emit red light. The green light emitting unit 203 may correspond to a green sub-pixel of the display panel and emit green light. It is understood that the color of the light emitted from the light emitting unit may not be limited to red, green, blue, but may be yellow or other colors.
As shown in fig. 2, each light emitting unit 200 includes an anode 210, an electron blocking layer 220, a light emitting layer 230, and a cathode 240, which are stacked.
The anode 210 may be formed of various conductive materials. For example, the anode 210 may be formed as a transparent electrode or a reflective electrode according to its use.
When the anode 210 is formed as a transparent electrode, the anode 210 may include Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), zinc oxide (ZnO), indium oxide (In2O3), or the like, when the anode 210 is formed as a reflective electrode, a reflective layer may be formed of Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a mixture thereof, and ITO, IZO, ZnO, In2O3, or the like may be formed on the reflective layer.
The light emitting layer 230 may be positioned on the anode 210, and the light emitting layer 230 may be formed of a small molecular weight organic material or a high molecular weight organic material.
The cathode 240 may be positioned on the light emitting layer 230. The cathode 240 may be formed as a transparent electrode or a reflective electrode. The cathode 240 may be a full-face electrode.
When the cathode 240 is formed as a transparent electrode, the cathode 240 may have a compound layer having a small work function, for example, Li, Ca, lithium fluoride/calcium (LiF/Ca), lithium fluoride/aluminum (LiF/Al), Al, Mg, or a combination thereof. The cathode 240 may also have a material layer such as ITO, IZO, ZnO, or In2O 3. When the cathode 240 is formed as a reflective electrode, the cathode 240 may include a layer such as Li, Ca, LiF/Al, Mg, or a mixture thereof.
If a voltage is applied between the anode 210 and the cathode 240, the light emitting layer 230 emits visible light, thereby implementing an image that can be recognized by a user.
The electron blocking layer 220 may be positioned between the anode 210 and the light emitting layer 230. The electron blocking layer 220 can block or slow down the electrons from continuing to the anode 210, thereby reducing the electron leakage current.
The electron blocking layer 220 of at least a portion of the light emitting unit 200 includes a first host material including a compound of a planar molecular structure and at least one first guest material including a compound of a non-planar molecular structure, and the hole transport ability of the electron blocking layer 220 in a direction perpendicular to the light emitting layer 230 (i.e., a direction perpendicular to the film layer) is greater than or equal to the hole transport ability in a direction parallel to the light emitting layer 230. In this way, the electron blocking layer 220 including the first host material and the first guest material can achieve a good effect of blocking electron transport, and can reduce the hole transport capability of the electron blocking layer 220 in a direction parallel to the light emitting layer 230 by the first guest material to reduce the lateral transport of holes, thereby avoiding improper lighting of other light emitting units 200 due to hole crosstalk as much as possible, and avoiding color crosstalk of the display panel as much as possible.
The electron blocking layer 220 may be formed mainly by co-evaporation or pre-mix evaporation of the first host material and the first guest material, and the electron blocking layer 220 has an isotropic thin film characteristic. Herein, isotropic film properties mean that the film layers have the same hole and/or electron transport capabilities in all directions (especially the direction perpendicular to the film layers and the direction parallel to the film layers). The weight proportion of the at least one first guest material in the electron blocking layer 220 is 1% to 50%. The electron blocking layer 220 mainly blocks electron transmission through the first host material, and controlling the weight ratio of the first guest material in the electron blocking layer 220 to be less than 50% can ensure that the proportion of the first host material is enough to ensure the effect of blocking electron transmission.
The first host material and the first guest material may each include an aromatic ring compound. The aromatic rings in the planar molecular structure in the first host material are in the same plane, and the aromatic rings in the non-planar molecular structure in the first guest material are distributed in an angle in space. The molecular structures with the aromatic rings in the same plane are easier to stack along the stacking direction of the aromatic rings, and the molecular structures with the aromatic rings distributed at angles in the space are not easy to stack along a single specific direction, so when the first host material and the first guest material are co-evaporated or pre-mixed evaporated to form the electron blocking layer 220, the single-direction stacking effect of the planar first host material can be destroyed by the non-planar first guest material, so that the hole transport capability of the electron blocking layer 220 along the direction perpendicular to the light-emitting layer 230 (i.e., the direction perpendicular to the film layer) is greater than or equal to the hole transport capability along the direction parallel to the light-emitting layer 230.
The first host material including the planar molecular structure has a good ability to block electron transport. The hole transport ability of the first host material is greater than that of the first guest material. In this way, the hole transport ability of the electron blocking layer 220 in the direction parallel to the light emitting layer 230 can be controlled by the first guest material, so that the hole transport ability of the electron blocking layer 220 in the direction perpendicular to the light emitting layer 230 (i.e., the direction perpendicular to the film layers) is greater than or equal to the hole transport ability in the direction parallel to the light emitting layer 230.
Referring to fig. 3 and 4 together, fig. 3 shows a schematic stacking diagram of a first host material according to an embodiment of the invention, and fig. 4 shows a schematic stacking diagram of a first host material and at least one first guest material according to an embodiment of the invention.
In the first host material shown in fig. 3, two compounds having a planar molecular structure are spaced apart from each other. When the first host material is formed on (e.g., evaporated on) the anode 210, especially when the first host material is evaporated alone, the compounds having the planar molecular structure are generally stacked in a direction parallel to the anode 210 (i.e., a direction parallel to the light-emitting layer 230) and are staggered in a direction perpendicular to the anode 210 (i.e., a direction perpendicular to the light-emitting layer 230), holes migrate along the direction of the molecular stack, and since there is a stronger pi-pi stacking (pi orbital electron cloud on benzene ring) between the compounds having the planar molecular structure in the direction parallel to the light-emitting layer 230, the electron cloud interacts strongly to facilitate electron delocalization, so that the hole transport ability in this direction is stronger, and since there is no pi-pi stacking (pi orbital electron cloud on benzene ring) between the molecules in the direction perpendicular to the light-emitting layer 230 (i.e., a direction perpendicular to the film), there is no overlap of electron clouds to be unfavorable for the hole transport, so that the first host material has a better hole transport ability in a direction parallel to the light emitting layer 230, while in a direction perpendicular to the light emitting layer 230, the hole transport ability in the direction perpendicular to the light emitting layer 230 is weaker than in the direction parallel to the light emitting layer 230 due to lack of stacking of effective molecules.
The first guest material has a weaker ability to block electron transport than the first host material. In the electron blocking layer 220, the higher the doping ratio of the first host material is, the better the effect of the ability to block electron transport is. The first guest material blocks the transport of holes in a direction perpendicular to the light-emitting layer 230 (i.e., perpendicular to the film layer) more than the first host material blocks the transport of holes in a direction perpendicular to the light-emitting layer 230 (i.e., perpendicular to the film layer).
As shown in fig. 4, the electron blocking layer 220 includes a first host material and at least one first guest material, and since the aromatic rings in the non-planar molecular structure of the first guest material are distributed at an angle in space, so that the arrangement of molecules in the first guest material is irregular and the action modes of the molecules in all directions are consistent, and the compound including the non-planar molecular structure of the first guest material has an adverse effect on the compound including the planar molecular structure of the first host material through the interaction of electron clouds, the first guest material can disturb the stack of the compound including the planar molecular structure of the first host material, so as to reduce the hole transport ability of the first host material in a direction parallel to the light emitting layer 230, reduce the transport of lateral holes, and improve the color crosstalk due to the improper light emission of other color light emitting units, thereby improving the color cast of the display panel. In the electron blocking layer 220, the higher the doping ratio of the first guest material is, the better the stacking disturbance effect of the first guest material on the compound including the planar molecular structure in the first host material is.
Also, a stack of compounds including a planar-type molecular structure can be partially formed in a direction perpendicular to the light emitting layer 230 (i.e., a direction perpendicular to the film layer) to increase hole transport ability of the first host material in the direction perpendicular to the light emitting layer 230, and transport of longitudinal holes can be increased, thereby improving current efficiency of the light emitting unit.
Wherein the first main material comprises any one of an acene derivative, an anthracene derivative and a triarylamine derivative. The first guest material includes one or more of carbazole derivatives and fluorene derivatives.
The display panel according to the embodiment of the invention includes a substrate 100 and a plurality of light emitting units 200, the electron blocking layer 220 of at least a part of the light emitting units 200 includes a first host material and at least one first guest material, the first host material includes a compound of a planar molecular structure, the first guest material includes a compound of a non-planar molecular structure, the hole transport capability of the electron blocking layer 220 in a direction perpendicular to the light emitting layer 230 is greater than or equal to the hole transport capability in a direction parallel to the light emitting layer 230, the transport of lateral current (holes) can be reduced, so that the current (holes) flowing from the blue light emitting unit 201 to the other color light emitting units through the common layer can be reduced when the blue light emitting unit 201 is turned on alone, therefore, color crosstalk caused by improper light emission of other color light-emitting units is improved, and the problem of color cast of the display panel is further improved. Moreover, according to the display panel of the embodiment of the invention, the hole transport capability of the electron blocking layer 220 in the direction perpendicular to the light emitting layer 230 can be improved, and thus the current efficiency of the light emitting unit 200 can be improved.
It should be noted that, conventionally, in order to reduce the cost when manufacturing the OLED display panel, the electron blocking layer 220 in each light emitting unit 200 is generally manufactured by using a common mask with a large opening, that is, the electron blocking layer 220 in each light emitting unit 200 and the electron blocking layer 220 in the adjacent light emitting unit 200 are in a continuous structure, that is, a common layer is formed.
Referring also to fig. 5, fig. 5 is an enlarged schematic view of an embodiment of the M region in fig. 2.
In some alternative embodiments, as shown in fig. 5, the light emitting unit 200 further includes a hole transport layer 250, and the hole transport layer 250 is positioned between the anode 210 and the electron blocking layer 220. In some alternative embodiments, the light emitting unit 200 further includes an electron transport layer 260 between the cathode 240 and the light emitting layer 230.
In some alternative embodiments, the red light emitting cell 202 includes an electron blocking layer 220 and a hole transport layer 250. The electron blocking layer 220 of the red light emitting unit 202 includes a first host material and at least one first guest material, the first host material includes a compound having a planar molecular structure, and the at least one first guest material includes a compound having a non-planar molecular structure. The HOMO level of the hole transport layer 250 of the red light emitting unit 202 is greater than the HOMO level of the first host material. In some embodiments, the HOMO level of the hole transport layer 250 of the red light emitting unit 202 is greater than the HOMO level of the first host material by 0.1eV to 0.5eV, thereby increasing the turn-on voltage of the red light emitting unit 202, and reducing the difference in turn-on voltage between the red light emitting unit 202 and the blue light emitting unit 201, so that the current flowing from the blue light emitting unit 201 to the red light emitting unit 202 through the common layer can be reduced when the blue light emitting unit 201 is turned on alone, thereby improving color crosstalk due to improper light emission of the red light emitting unit 202, and further improving the color shift problem of the display panel.
In some alternative embodiments, the green light emitting unit 203 includes an electron blocking layer 220 and a hole transport layer 250. The electron blocking layer 220 of the green light emitting unit 203 includes a first host material and at least one first guest material, the first host material includes a compound having a planar molecular structure, and the at least one first guest material includes a compound having a non-planar molecular structure. The HOMO level of the hole transport layer 250 of the green light emitting unit 203 is greater than the HOMO level of the first host material. In some embodiments, the HOMO level of the hole transport layer 250 of the green light emitting unit 203 is greater than the HOMO level of the first host material by 0.1eV to 0.5eV, thereby increasing the turn-on voltage of the green light emitting unit 203, and reducing the difference in turn-on voltage between the green light emitting unit 203 and the blue light emitting unit 201, so that the current flowing from the blue light emitting unit 201 to the green light emitting unit 203 through the common layer can be reduced when the blue light emitting unit 201 is turned on alone, thereby improving color crosstalk due to improper light emission of the green light emitting unit 203, and further improving the color shift problem of the display panel.
In some alternative embodiments, the red light emitting unit 202 and the green light emitting unit 203 include an electron blocking layer 220 and a hole transport layer 250. The electron blocking layer 220 of the red light emitting unit 202 and the green light emitting unit 203 includes a first host material and at least one first guest material, the first host material includes a compound having a planar molecular structure, and the at least one first guest material includes a compound having a non-planar molecular structure. The HOMO levels of the hole transport layers 250 of the red and green light emitting units 202 and 203 are greater than the HOMO level of the first host material. In some embodiments, the HOMO levels of the hole transport layers 250 of the red and green light emitting units 202 and 203 are greater than the HOMO level of the first host material by 0.1eV to 0.5eV, thereby increasing the turn-on voltage of the red light emitting unit 202 and reducing the difference in turn-on voltage between the red and green light emitting units 202 and 203 and the blue light emitting unit 201, so that the current flowing from the blue light emitting unit 201 to the red and green light emitting units 202 and 203 through the common layer can be reduced when the blue light emitting unit 201 is turned on alone, thereby improving color crosstalk due to improper light emission of the red and green light emitting units 202 and 203 and further improving the color shift problem of the display panel.
An embodiment of the invention provides a display device, which comprises the display panel according to any one of the embodiments. The display device can be an electronic device such as a mobile phone, a tablet personal computer, a display, a notebook computer and an intelligent wearable device. Since the display device according to the embodiment of the invention includes the display panel according to the embodiment of the invention, the display panel according to the embodiment has the advantages.
In accordance with the above-described embodiments of the present invention, these embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. The invention is limited only by the claims and their full scope and equivalents.
Claims (10)
1. A display panel, comprising:
a substrate;
a plurality of light emitting units disposed on the substrate;
each light-emitting unit comprises an anode, an electron blocking layer, a light-emitting layer and a cathode which are arranged in a stacked mode, at least part of the electron blocking layer of each light-emitting unit comprises a first host material and at least one first guest material, the first host material comprises a compound with a planar molecular structure, the at least one first guest material comprises a compound with a non-planar molecular structure, and the hole transport capacity of the electron blocking layer in the direction perpendicular to the light-emitting layer is larger than or equal to that in the direction parallel to the light-emitting layer.
2. The display panel of claim 1, wherein the electron blocking layer is formed primarily by co-evaporation or pre-mix evaporation of the first host material and at least one of the first guest materials, and wherein the electron blocking layer has isotropic thin film properties.
3. The display panel according to claim 1, wherein the first host material and the first guest material each include an aromatic ring compound.
4. The display panel of claim 3, wherein the aromatic rings in the planar molecular structure in the first host material are in the same plane;
preferably, the first host material includes any one of an acene derivative, an anthracene derivative, and a triarylamine derivative.
5. The display panel of claim 3, wherein the aromatic rings in the non-planar molecular structure of the first guest material are spatially angularly distributed;
preferably, the first guest material includes one or more of a carbazole derivative, a fluorene derivative.
6. The display panel according to claim 1, wherein the weight proportion of the at least one first guest material in the electron blocking layer is 1% to 50%.
7. The display panel of claim 1, wherein the first host material has a hole transport capability greater than a hole transport capability of the first guest material;
the first guest material blocks the transport of holes in a direction perpendicular to the light emitting layer more than the first host material blocks the transport of holes in a direction perpendicular to the light emitting layer.
8. The display panel according to claim 1, wherein the light-emitting unit further comprises a hole transport layer between the anode and the electron blocking layer;
preferably, the light emitting unit further includes an electron transport layer between the cathode and the light emitting layer.
9. The display panel according to claim 8, wherein the plurality of light-emitting units include a red light-emitting unit, a green light-emitting unit, and a blue light-emitting unit;
preferably, the red light emitting unit and/or the green light emitting unit includes the electron blocking layer and the hole transporting layer, the electron blocking layer of the red light emitting unit and/or the green light emitting unit includes the first host material, and a HOMO level of the hole transporting layer is greater than a HOMO level of the first host material;
preferably, the HOMO level of the hole transport layer is 0.1eV to 0.5eV greater than the HOMO level of the first host material.
10. A display device characterized by comprising the display panel according to any one of claims 1 to 9.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113130804A (en) * | 2021-04-02 | 2021-07-16 | 昆山国显光电有限公司 | Display panel |
| CN114361352A (en) * | 2021-12-29 | 2022-04-15 | 湖北长江新型显示产业创新中心有限公司 | Semiconductor device, display panel and device, optical storage device and method of using the same |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102983280A (en) * | 2011-09-07 | 2013-03-20 | 海洋王照明科技股份有限公司 | Organic electroluminescence device and preparation method thereof |
| CN103579527A (en) * | 2012-07-27 | 2014-02-12 | 海洋王照明科技股份有限公司 | Organic light-emitting device and preparation method thereof |
| CN104934544A (en) * | 2014-03-21 | 2015-09-23 | 海洋王照明科技股份有限公司 | Organic electroluminescent light emitting device and preparation method thereof |
| US20150311463A1 (en) * | 2014-04-29 | 2015-10-29 | Lg Display Co., Ltd. | Organic light emitting device |
| CN108963093A (en) * | 2018-06-29 | 2018-12-07 | 云谷（固安）科技有限公司 | Organic electroluminescence device and Organnic electroluminescent device |
| CN108963109A (en) * | 2018-06-29 | 2018-12-07 | 云谷（固安）科技有限公司 | A kind of Organnic electroluminescent device |
| CN111293228A (en) * | 2020-02-25 | 2020-06-16 | 昆山国显光电有限公司 | Light emitting device and display panel |
| US20200227492A1 (en) * | 2019-01-11 | 2020-07-16 | Japan Display Inc. | Electroluminescence display device and manufacturing method thereof |
-
2020
- 2020-08-24 CN CN202010856356.0A patent/CN111952477B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102983280A (en) * | 2011-09-07 | 2013-03-20 | 海洋王照明科技股份有限公司 | Organic electroluminescence device and preparation method thereof |
| CN103579527A (en) * | 2012-07-27 | 2014-02-12 | 海洋王照明科技股份有限公司 | Organic light-emitting device and preparation method thereof |
| CN104934544A (en) * | 2014-03-21 | 2015-09-23 | 海洋王照明科技股份有限公司 | Organic electroluminescent light emitting device and preparation method thereof |
| US20150311463A1 (en) * | 2014-04-29 | 2015-10-29 | Lg Display Co., Ltd. | Organic light emitting device |
| CN108963093A (en) * | 2018-06-29 | 2018-12-07 | 云谷（固安）科技有限公司 | Organic electroluminescence device and Organnic electroluminescent device |
| CN108963109A (en) * | 2018-06-29 | 2018-12-07 | 云谷（固安）科技有限公司 | A kind of Organnic electroluminescent device |
| US20200227492A1 (en) * | 2019-01-11 | 2020-07-16 | Japan Display Inc. | Electroluminescence display device and manufacturing method thereof |
| CN111293228A (en) * | 2020-02-25 | 2020-06-16 | 昆山国显光电有限公司 | Light emitting device and display panel |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113130804A (en) * | 2021-04-02 | 2021-07-16 | 昆山国显光电有限公司 | Display panel |
| CN113130804B (en) * | 2021-04-02 | 2022-09-20 | 昆山国显光电有限公司 | Display panel |
| CN114361352A (en) * | 2021-12-29 | 2022-04-15 | 湖北长江新型显示产业创新中心有限公司 | Semiconductor device, display panel and device, optical storage device and method of using the same |
| CN114361352B (en) * | 2021-12-29 | 2024-02-02 | 湖北长江新型显示产业创新中心有限公司 | Semiconductor device, display panel and device, optical storage device and use method thereof |
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|---|---|
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