Light-emitting device, preparation method, and electronic apparatus

Abstract

A light-emitting device, a preparation method, and an electronic apparatus. The light-emitting device is prepared by means of the following method: providing a substrate (100) provided with a first electrode (200); forming a light-emitting layer (300), the preparation of the light-emitting layer (300) comprising: forming, on the first electrode (200), a first material layer comprising a first light-emitting material, forming an exposure region and a non-exposure region in the first material layer, and removing the first material layer of at least a part of the exposure region or at least a part of the non-exposure region by means of a first solvent, to obtain a first light-emitting unit (301); and forming, on the first electrode (200), a second material layer comprising a second light-emitting material, forming an exposure region and a non-exposure region in the second material layer, and removing the second material layer of at least a part of the exposure region or at least a part of the non-exposure region by means of a second solvent, to obtain a second light-emitting unit (302); and forming a second electrode (400) on the light-emitting layer, the polarity of the second solvent being different from that of the first light-emitting material. The light-emitting device prepared by means of the preparation method has excellent light-emitting performance.

Description

Light-emitting device, preparation method and electronic device Technical Field

[0001] The present application relates to the field of optoelectronic devices, and in particular to a light-emitting device, a preparation method and an electronic device. Background Art

[0002] Light-emitting devices, such as light-emitting diodes (LEDs), are widely used in the display field. In display devices, the light-emitting layer prepared by photolithography is fully eluted during the development process to reduce color mixing. However, the degree of elution can affect device performance. Technical issues

[0003] The purpose of this application is to provide a light-emitting device, a preparation method and an electronic device, which can solve the technical problem of poor performance of existing light-emitting devices. Technical Solutions

[0004] According to the first embodiment of the present application, the method for preparing the light-emitting device includes:

[0005] providing a substrate provided with a first electrode;

[0006] forming a light-emitting layer on a side of the first electrode facing away from the substrate;

[0007] The preparation of the light-emitting layer includes:

[0008] forming a first material layer including a first light-emitting material on the first electrode, forming an exposed area and a non-exposed area in the first material layer, and removing at least a portion of the exposed area or at least a portion of the first material layer in the non-exposed area using a first solvent to obtain a first light-emitting unit;

[0009] forming a second material layer including a second light-emitting material on the first electrode, forming an exposed area and a non-exposed area in the second material layer, and removing at least a portion of the exposed area or at least a portion of the second material layer in the non-exposed area by a second solvent to obtain a second light-emitting unit;

[0010] forming a second electrode on the light-emitting layer;

[0011] The first light-emitting unit and the second light-emitting unit are arranged along the first direction of the substrate, the first light-emitting unit is used to emit light in a first wavelength range, and the second light-emitting unit is used to emit light in a second wavelength range, the first wavelength range is different from the second wavelength range, and the polarity of the second solvent is different from the polarity of the first light-emitting material.

[0012] Optionally, the preparation of the light-emitting layer further comprises:

[0013] A third material layer including a third light emitting material is formed on the first electrode.

[0014] In some embodiments, an exposed area and a non-exposed area are formed in the third material layer, and at least a portion of the exposed area or at least a portion of the non-exposed area of ​​the third material layer is removed by a third solvent to obtain a third light-emitting unit;

[0015] The third light emitting unit is configured to emit light in a third wavelength range, where the third wavelength range is different from the first wavelength range and the second wavelength range;

[0016] The polarity of the third solvent is different from the polarity of the first luminescent material or the polarity of the second luminescent material.

[0017] In some embodiments, the first luminescent material, the second luminescent material, or the third luminescent material comprises a quantum dot material.

[0018] Optionally, the quantum dot material includes at least one of CdSe / ZnSe, CdSe / ZnS, CdSe / ZnSe / ZnS, CdS / ZnSe, CdS / ZnS, ZnSe / ZnS, ZnTeSe / ZnS, InP / ZnSe / ZnS and InP / ZnS.

[0019] Optionally, the ligand of the quantum dot material includes at least one of alkyl carboxylic acid, alkyl phosphonic acid, alkyl phosphinic acid, alkyl thiol, alkyl amine, acrylate-substituted acid, halogen, mercapto alcohol, carboxyl alcohol and amino alcohol.

[0020] Optionally, the first solvent, the second solvent or the third solvent includes at least one of hydrocarbon solvents, alkyl alcohol solvents, ether and acetal solvents, halogenated hydrocarbon solvents, ester solvents and nitrogen-containing compound solvents.

[0021] Optionally, the first luminescent material has a different polarity from the second solvent and the third solvent.

[0022] Optionally, the first material layer, the second material layer or the third material layer contains a photosensitive crosslinking agent.

[0023] Optionally, the photosensitive crosslinker includes at least one of an azide compound and a free radical photoinitiator.

[0024] Optionally, the substrate has a plurality of isolation structures, and the light-emitting layer is divided into a plurality of light-emitting units by the isolation structures.

[0025] Optionally, the isolation structure has a first surface, and the material of the first surface is amphiphilic.

[0026] Optionally, a first functional layer is formed between the first electrode and the light-emitting layer, and the first functional layer includes at least one of a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, an electron transport layer, an electron blocking layer and a buffer layer.

[0027] Optionally, a second functional layer is formed between the light-emitting layer and the second electrode, and the second functional layer includes at least one of a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, an electron transport layer, an electron blocking layer and a buffer layer.

[0028] Optionally, the mass percentage concentration of the quantum dot material is 1 to 50 wt%.

[0029] According to the light-emitting device in the second embodiment of the present application, the light-emitting device is prepared by the above-mentioned preparation method.

[0030] An electronic device according to a third embodiment of the present application includes the above-mentioned light-emitting device. Beneficial effects

[0031] The method for preparing a light-emitting device according to the embodiment of the present application has at least the following technical effects:

[0032] The present application adopts luminescent materials and elution solvents of different polarities when preparing different luminescent units, thereby reducing the performance loss of the luminescent material during the elution process, improving the external quantum efficiency of the luminescent device, and enhancing the luminescent performance of the luminescent device. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0034] FIG1 is a flow chart of the preparation of a light-emitting device in some embodiments of the present application;

[0035] FIG2 is a flow chart of the preparation of a light-emitting device in some embodiments of the present application;

[0036] FIG3 is a flow chart of the preparation of a light-emitting device in some embodiments of the present application;

[0037] FIG4 is a flow chart of preparing a light-emitting device in some embodiments of the present application;

[0038] FIG5 is a flowchart of preparing a light-emitting device in some embodiments of the present application;

[0039] FIG6 is a flowchart of preparing a light-emitting device in some embodiments of the present application;

[0040] FIG7 is a flowchart of preparing a light-emitting device in some embodiments of the present application;

[0041] FIG8 is a schematic structural diagram of a light-emitting device in some embodiments of the present application;

[0042] FIG9 is a flowchart of manufacturing light-emitting devices in other embodiments of the present application;

[0043] FIG10 is a schematic structural diagram of a light-emitting device in some other embodiments of the present application;

[0044] FIG11 is a schematic structural diagram of a light-emitting device in some other embodiments of the present application;

[0045] In the figure, 100-substrate, 101-isolation structure, 110-first surface, 200-first electrode, 300-light-emitting layer, 301-first light-emitting unit, 302-second light-emitting unit, 303-third light-emitting unit, 400-second electrode, 500-first functional layer, 501-hole injection layer, 502-hole transport layer, 600-second functional layer. Modes for Carrying Out the Invention

[0046] The following, in conjunction with the accompanying drawings, provides a clear and complete description of the technical solutions in the embodiments of the present application. It should be noted that the described embodiments are only a portion of the embodiments of the present application, and not all of the embodiments. All other embodiments derived by persons skilled in the art based on the embodiments of the present application without inventive effort are within the scope of protection of the present application. Furthermore, in the description of the present application, the term "including" means "including but not limited to." The terms "first," "second," and "third," etc., are used merely as designations and do not impose numerical requirements or establish a sequence. Various embodiments of the present application may be presented in the form of a range. It should be understood that describing in a range format is merely for convenience and brevity and should not be construed as a rigid limitation on the scope of the present application. Therefore, the range description should be considered to specifically disclose all possible subranges and individual numerical values ​​within the range. For example, a range description of 1 to 6 should be considered to specifically disclose subranges, such as 1 to 3, 1 to 4, 1 to 5, 2 to 4, 2 to 6, 3 to 6, etc., as well as individual numerical values ​​within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Additionally, whenever a numerical range is indicated herein, it is meant to include any cited numeral (fractional or integral) within the indicated range.

[0047] References to "left," "right," "front," "back," "top," "bottom," "up," "down," "high," "low," and the like in this application, if any, are for descriptive purposes and are not necessarily intended to describe fixed relative positions. It should be understood that the terms used in this manner are interchangeable where appropriate, such that the embodiments disclosed herein described herein, for example, can operate in orientations other than those shown or otherwise described herein. For example, when the device in the accompanying drawings is inverted, a feature previously described as being "above" another feature may now be described as being "below" the other feature. The device may also be oriented in other ways (rotated 90 degrees or in other orientations), in which case relative spatial relationships will be interpreted accordingly. References to an element being "above" another element in this application may be directly above the other element, or one or more intervening elements may be present. In addition, the drawings in this application only illustrate cross-sectional views of a portion of a light-emitting device. The first direction X in this application is transverse, the second direction Y is longitudinal, and the second direction Y is also the thickness direction of each structure. The first direction X and the second direction Y intersect, or the first direction X and the second direction Y are perpendicular or relatively perpendicular.

[0048] The light-emitting device is a structure in which various functional layers are stacked on a substrate 100 formed with a TFT (Thin Film Transistor). The area surrounded by the isolation structure 101 provided on the substrate 100 is a pixel area of ​​various colors. The pixel area can be of various shapes, and multiple pixel areas can form a matrix. Taking a light-emitting device having RGB pixel areas as an example, the substrate 100 is divided into a red pixel area RP, a green pixel area GP, and a blue pixel area BP by the isolation structure 101. During the preparation process, if the different pixel areas are to be washed more thoroughly to reduce the occurrence of color mixing, the performance loss of the light-emitting device will be relatively large. To address the above-mentioned problems, embodiments of the present application provide a method for preparing a light-emitting device, comprising: providing a substrate 100 provided with a first electrode 200; forming a light-emitting layer 300 on a side of the first electrode 200 facing away from the substrate 100; preparing the light-emitting layer 300 comprising: forming a first material layer comprising a first light-emitting material on the first electrode 200, forming an exposed region and a non-exposed region in the first material layer, and removing at least a portion of the exposed region or at least a portion of the first material layer in the non-exposed region using a first solvent to obtain a first light-emitting unit 301; forming a second material layer comprising a second light-emitting material on the first electrode 200, forming an exposed region and a non-exposed region in the second material layer, and removing at least a portion of the exposed region or at least a portion of the second material layer in the non-exposed region using a second solvent to obtain a second light-emitting unit 302; and forming a second electrode 400 on the light-emitting layer 300;

[0049] The first light-emitting unit 301 and the second light-emitting unit 302 are arranged along the first direction X of the substrate 100. The first light-emitting unit 301 is used to emit light in a first wavelength range, and the second light-emitting unit 302 is used to emit light in a second wavelength range. The first wavelength range is different from the second wavelength range, and the polarity of the second solvent is different from the polarity of the first light-emitting material.

[0050] In some embodiments, the light-emitting device of the present application comprises a structure in which various layers are stacked on a substrate 100 having a thin film transistor (TFT). The first electrode 200 is electrically connected to the TFT, and the substrate 100 is a patterned array substrate. In some embodiments, the first electrode 200 is a light-transmitting anode and may comprise a transparent oxide such as ITO, IZO, or AZO. Furthermore, the first electrode 200 may comprise one or more conductive layers.

[0051] In this application, the polarity of the second solvent described is different from the polarity of the first luminescent material. Alternatively, the second solvent may be a non-polar solvent and the first material may be a polar material; or the second solvent may be a polar solvent and the first material may be a non-polar material. The light-emitting device of this application uses light-emitting materials and elution solvents of different polarities when preparing different light-emitting units, thereby reducing the performance loss of the light-emitting material during the elution process, improving the external quantum efficiency of the light-emitting device, and enhancing the luminescence performance of the light-emitting device.

[0052] In some embodiments, the preparation of the light-emitting layer 300 further includes: forming a third material layer including a third light-emitting material on the first electrode 200 .

[0053] In some embodiments, the third material layer is subjected to the following steps: forming an exposed region and a non-exposed region in the third material layer; removing at least a portion of the exposed region or at least a portion of the non-exposed region of the third material layer using a third solvent to obtain a third light-emitting unit 303; the third light-emitting unit 303 is configured to emit light in a third wavelength range, the third wavelength range being different from the first wavelength range and the second wavelength range; and the polarity of the third solvent being different from the polarity of the first light-emitting material or the polarity of the second light-emitting material. When preparing different light-emitting units, the present application reduces performance loss of the light-emitting units during the elution process by using light-emitting materials and elution solvents of different polarities.

[0054] In some embodiments, after forming the exposure area and the non-exposure area, the first material layer, the second material layer or the third material layer is dried or baked to remove the solvent in the first material layer, the second material layer or the third material layer, where the solvent is used to disperse or dissolve the luminescent material in the material layer.

[0055] In some embodiments, the light emitting layer 300 includes a first light emitting unit 301 , a second light emitting unit 302 , and a third light emitting unit 303 , and the first light emitting unit 301 , the second light emitting unit 302 , and the third light emitting unit 303 are arranged along the first direction X.

[0056] In some embodiments, the first light-emitting unit 301 is configured to emit light within a first wavelength range, the second light-emitting unit 302 is configured to emit light within a second wavelength range, and the third light-emitting unit 303 is configured to emit light within a third wavelength range. In some specific implementations, the first wavelength range is 600-780 nm, the first light-emitting unit is configured to emit red light, the second wavelength range is 500-600 nm, the second light-emitting unit 302 is configured to emit green light, the third wavelength range is 400-500 nm, and the third light-emitting unit 303 is configured to emit blue light.

[0057] In some embodiments, the first light-emitting unit 301, the second light-emitting unit 302, or the third light-emitting unit 303 in the present application is formed by positive photolithography. Taking the first light-emitting unit 301 as an example, the first light-emitting unit 301 is prepared by the following method: a first material layer including a first light-emitting material is formed on the first electrode 200, a patterned mask is set above the first material layer, and exposure is performed to form exposed areas and non-exposed areas in the first material layer. The exposed areas are removed by a first solvent, and the unexposed first material layer is retained under the opaque mask. The retained first material layer forms the first light-emitting unit 301. The second light-emitting unit 302 or the third light-emitting unit 303 can be prepared using the same preparation method as the first light-emitting unit 301, or the second light-emitting unit 302 or the third light-emitting unit 303 can be prepared using a preparation method different from that of the first light-emitting unit 301.

[0058] In some embodiments, the first light-emitting unit 301, the second light-emitting unit 302, or the third light-emitting unit 303 in the present application is formed by negative photolithography. Taking the first light-emitting unit 301 as an example, the first light-emitting unit 301 is prepared by the following method: a first material layer including a first light-emitting material is formed on the first electrode 200, a patterned mask is set above the first material layer, and exposure is performed to form exposed areas and non-exposed areas in the first material layer. The exposed areas are cross-linked and cured due to the exposure, and the non-exposed areas are removed by a first solvent. The first material layer in the exposed areas forms the first light-emitting unit 301. The second light-emitting unit 302 or the third light-emitting unit 303 can be prepared using the same preparation method as the first light-emitting unit 301, or the second light-emitting unit 302 or the third light-emitting unit 303 can be prepared using a preparation method different from that of the first light-emitting unit 301.

[0059] In some embodiments, the first light-emitting material, the second light-emitting material or the third light-emitting material includes a quantum dot material. In some specific embodiments, the quantum dot material includes RQD (red quantum dot material), GQD (green quantum dot material) and BQD (blue quantum dot material). The fluorescence bands emitted by RQD, GQD and BQD are different, and they emit red, green and blue as fluorescence, respectively. In addition to quantum dots RQD, GQD and BQD, the light-emitting layer may also include, for example, quantum dots that emit yellow as fluorescence. The quantum dot material may include a II-VI semiconductor compound, a III-V semiconductor compound, a III-VI semiconductor compound, a I-III-VI semiconductor compound, a IV-VI semiconductor compound, a Group IV element or compound; or any combination thereof. In other specific embodiments, the quantum dots RQD, GQD and BQD have a core-shell structure and may include at least one of materials such as CdSe / ZnSe, CdSe / ZnS, CdSe / ZnSe / ZnS, CdS / ZnSe, CdS / ZnS, ZnTeSe / ZnS, InP / ZnSe / ZnS and InP / ZnS.

[0060] In some embodiments, the first luminescent material is a non-polar quantum dot material, the first solvent is a non-polar solvent, the second luminescent material is a polar quantum dot material, the second solvent is a polar solvent, the third luminescent material is a polar quantum dot luminescent material, and the third solvent is a polar solvent; or, the first luminescent material is a polar quantum dot material, the first solvent is a polar solvent, the second luminescent material is a non-polar quantum dot material, the second solvent is a non-polar solvent, the third luminescent material is a non-polar quantum dot material, and the third solvent is a non-polar solvent; or, the first luminescent material is a polar quantum dot material, the first solvent is a polar solvent, the second luminescent material is a non-polar quantum dot material, the second solvent is a non-polar solvent, the third luminescent material is a polar quantum dot luminescent material, and the third solvent is a polar solvent; or, the first luminescent material is a polar quantum dot material material, the first solvent is a polar solvent, the second luminescent material is a polar quantum dot material, the second solvent is a polar solvent, the third luminescent material is a non-polar quantum dot luminescent material, and the third solvent is a non-polar solvent; or, the first luminescent material is a non-polar quantum dot material, the first solvent is a non-polar solvent, the second luminescent material is a non-polar quantum dot material, the second solvent is a non-polar solvent, the third luminescent material is a polar quantum dot material, and the third solvent is a polar solvent; or, the first luminescent material is a non-polar quantum dot material, the first solvent is a non-polar solvent, the second luminescent material is a polar quantum dot material, the second solvent is a polar solvent, the third luminescent material is a non-polar quantum dot luminescent material, and the third solvent is a non-polar solvent.

[0061] In this application, the polarity of a substance can be characterized by its dielectric constant. When the dielectric constant ε of a substance satisfies: 0 < ε ≤ 5, the substance is a non-polar substance. When the dielectric constant ε of a substance satisfies: 5 < ε ≤ 100, the substance is a polar substance.

[0062] In some embodiments, the ligands of the quantum dot material include at least one of a non-polar ligand and a polar ligand. In some embodiments, the solvent solubility characteristics of the quantum dot material are primarily determined by its surface ligands. For example, in other embodiments, the polarity of the luminescent material refers to whether the ligands on the quantum dot surface are polar or non-polar ligands.

[0063] The non-polar ligand includes an alkyl carboxylic acid, an alkyl phosphonic acid, an alkyl phosphinic acid, an alkyl thiol or an alkyl amine. The alkyl group in this application includes a saturated branched alkyl group, a branched alkyl group, and an unsaturated alkyl group. In some embodiments, the alkyl group in this paragraph has 1 to 18 carbon atoms.

[0064] In certain embodiments, alkyl carboxylic acids include saturated alkyl carboxylic acids, branched alkyl carboxylic acids, and unsaturated alkyl carboxylic acids, such as oleic acid. Alkyl phosphonic acids include saturated alkyl phosphonic acids, branched alkyl phosphonic acids, and unsaturated alkyl phosphonic acids, such as octylphosphonic acid, etc. Alkyl phosphinic acids include saturated alkyl phosphinic acids, branched alkyl phosphinic acids, and unsaturated alkyl phosphinic acids, such as hexyl hypophosphorous acid, octyl hypophosphorous acid, and dodecyl hypophosphorous acid, etc. Alkyl mercaptan includes saturated alkyl mercaptan and branched alkyl mercaptan, such as 2-ethylhexyl mercaptan, octyl mercaptan, nonyl mercaptan, decyl mercaptan, undecyl mercaptan, dodecyl mercaptan, tridecyl mercaptan, tetradecyl mercaptan, hexadecyl mercaptan, or octadecyl mercaptan, etc. Alkylamines include saturated alkylamines, branched alkylamines, and unsaturated alkylamines, such as oleylamine, etc.

[0065] Polar ligands include acrylate-substituted acids, halogens, mercapto alcohols, carboxyl alcohols, or amino alcohols. Acrylate-substituted acids include acrylic acid, 2-(2-methyl-acryloyl)oxyethyl succinate, and 2-(2-acryloyloxy)hydroxyethanol succinate. Halogens include fluorine, chlorine, bromine, and iodine. Mercapto alcohols include 2-mercaptoethanol, 3-mercapto-1-propanol, 4-mercapto-1-butanol, 5-mercapto-1-pentanol, 6-mercapto-1-hexanol, and 8-mercapto-1-octanol. Carboxyl alcohols include glycolic acid, hydroxypropionic acid, hydroxybutyric acid, hydroxyvaleric acid, hydroxycaproic acid, hydroxyoctanoic acid, hydroxyheptanoic acid, hydroxybenzoic acid, hydroxyphenylacetic acid, hydroxyphenylpropionic acid, hydroxyphenylbutyric acid, hydroxyphenyl acid, hydroxyphenylcaproic acid, or hydroxyphenylalanine. Amino alcohols include ethanolamine.

[0066] In some embodiments, the ligand of the quantum dot material includes a ligand for cross-linking between quantum dot materials under light irradiation, such as mono-2-(2-methyl-acryloyl)oxyethyl succinate.

[0067] In some embodiments, the first solvent, the second solvent, or the third solvent as the developing solvent includes at least one of a polar solvent or a non-polar solvent.

[0068] The non-polar solvent includes a hydrocarbon solvent, for example, an alkane, an alkene or an alkyne, preferably a hydrocarbon solvent having 6 to 40 carbon atoms. The alkane is a straight-chain alkane, a branched-chain alkane, a cycloalkane or an alkylbenzene, and at least one of octane, cyclohexane, tetradecane, toluene, octylbenzene and mixtures thereof can be cited.

[0069] In some embodiments, the polar solvent includes at least one of an alkyl alcohol solvent, an ether and acetal solvent, a halogenated hydrocarbon solvent, an ester solvent, and a nitrogen-containing compound solvent.

[0070] Alkyl alcohol solvents include straight-chain alkyl alcohols or branched-chain alkyl alcohols, and polyols such as methanol, ethanol, propylene glycol, and glycerol can be listed; ether and acetal solvents include alcohol ethers, such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, glycerol ether, etc.; halogenated hydrocarbon solvents include chloroform, dichloromethane, etc.; ester solvents include propylene glycol monomethyl ester, propylene glycol methyl ether acetate, ethyl acetate, ethyl benzoate, etc.; nitrogen-containing compound solvents include acetonitrile.

[0071] In some embodiments, the first material layer, the second material layer, or the third material layer of the present application contains a photosensitive material, and the photosensitive material includes at least one of a photosensitive crosslinker, a photopolymerization initiator, and a photoacid generator. In some embodiments, at least one of the first material layer, the second material layer, or the third material layer of the present application does not include a photosensitive material; or the first light-emitting unit, the second light-emitting unit, or the third light-emitting unit is not formed by exposure (photolithography). It should be understood that the expression "does not include a photosensitive material" in the present application means that the first material layer, the second material layer, or the third material layer absolutely does not contain a photosensitive material or relatively does not contain a photosensitive material. Relatively not containing a photosensitive material means that the photosensitive material in the first material layer, the second material layer, or the third material layer does not perform its photosensitivity function.

[0072] In some embodiments, the photosensitive crosslinker includes at least one of an azide compound and a free radical photoinitiator.

[0073] In some embodiments, the photosensitive crosslinker includes an azide compound, such as a phenyl azide compound, such as (1E,4E)-1,5-bis(4-azido-2,3,5,6-tetrafluorophenyl)penta-1,4-dien-3-one.

[0074] In some embodiments, the photosensitive crosslinker includes a free radical photoinitiator, such as ethyl 2,4,6-trimethylbenzoylphenylphosphonate.

[0075] In some embodiments, the first material layer, the second material layer, or the third material layer contains a solvent that dissolves the corresponding luminescent material, and the solvent is removed after the exposure process, such as by heating and volatilization. The solvent that dissolves the luminescent material has the same polarity as the corresponding luminescent material.

[0076] In some embodiments, the mass percentage concentration of the quantum dot material is 1 to 50 wt % based on the total mass of the material layer (including the solvent). For example, the mass percentage concentration of the quantum dot material is 20 to 30 wt %. For example, the mass percentage concentration of the quantum dot material can be any value of 1 wt %, 5 wt %, 10 wt %, 15 wt %, 20 wt %, 25 wt %, 30 wt %, 35 wt %, 40 wt %, 45 wt %, or 50 wt %, or a range consisting of any two values. In some embodiments, the mass fraction of the quantum dot material is 50 to 100 % based on the total mass of the light-emitting unit.

[0077] In some embodiments, the mass percentage concentration of the photosensitive material is 0.01 to 2 wt% based on the total mass of the material layer (including solvent). For example, the mass percentage concentration of the photosensitive material can be any value among 0.02 wt%, 0.05 wt%, 0.06 wt%, 0.08 wt%, 1 wt%, 1.2 wt%, 1.5 wt%, 1.8 wt%, or a range consisting of any two values.

[0078] In some embodiments, the substrate 100 of the present application has a plurality of isolation structures 101, and the light-emitting layer 300 is divided into a plurality of light-emitting units by the isolation structures 101. In other embodiments, the isolation structure has a first surface 110, and the material of the first surface 110 is amphiphilic. The use of amphiphilic materials on the surface of the isolation structure of the present application can increase the compatibility between the isolation structure 101 and the light-emitting material, thereby improving the overall performance of the light-emitting device. In addition, the height of the isolation structure 101 can be designed according to actual needs. In some embodiments, the height of the isolation structure 101 can be lower than that of the light-emitting layer 300. In some embodiments, the amphiphilic material can be listed as an amphiphilic polyurethane material.

[0079] In some embodiments, a first functional layer 500 is provided between the first electrode 200 and the light-emitting layer 300. The first functional layer 500 includes at least one of a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, an electron transport layer, an electron blocking layer, and a buffer layer. A second functional layer 600 is provided between the light-emitting layer 300 and the second electrode 400. The second functional layer 600 includes at least one of a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, an electron transport layer, an electron blocking layer, and a buffer layer. In some light-emitting device structures, the first functional layer 500 includes a hole injection layer 501 and a hole transport layer 502, and the second functional layer 600 includes an electron transport layer.

[0080] Taking the first electrode 200 as an anode as an example, the first functional layer 500 is disposed on the first electrode 200, the hole injection layer 501 may include (3,4-ethylenedioxythiophene) / polystyrene parasulfonate (PEDOT / PSS), and the hole transport layer 502 may include N-vinylcarbazole (PVK), poly (N, N'-bis (4-butylphenyl) -N, N'-bis (phenyl) benzidine) (poly-TPD), 4,4'-N, N'-dicarbazolyl-biphenyl (CBP), 4,4-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD) or poly (9,9'-dioctylfluorene-co-N- (4-butylphenyl) diphenylamine (TFB) and other organic materials, or a hole. The hole transport layer 502 may include inorganic materials such as NiO or MoO3. Those skilled in the art will appreciate that a variety of methods can be used to prepare the first functional layer 500. The thickness of the hole injection layer 501 may range from tens to hundreds of nanometers, for example, 20-300 nanometers, preferably 30-150 nanometers; the thickness of the hole transport layer 502 may range from tens to hundreds of nanometers, for example, 10-200 nanometers, preferably 15-100 nanometers. The hole transport layer may have i) a single-layer structure consisting of a single layer composed of a single substance, ii) a single-layer structure consisting of a single layer comprising multiple different substances, or iii) a multi-layer structure comprising multiple layers comprising multiple different substances.

[0081] The second functional layer 600 includes an electron transport layer, which may include 1,4,5,8-naphthalene-tetracarboxylic dianhydride (NTCDA), bathocuproine (BCP), tris[3-(3-pyridyl)-yl]borane (3TPYMB), LiF, tris(8-hydroxyquinoline)aluminum (Alq3), tris(8-hydroxyquinoline)gallium (Gaq3), tris(8-hydroxyquinoline)indium (Inq3), di(8-hydroxyquinoline)zinc (Z nq2), bis(2-(2-hydroxyphenyl)benzothiazole)zinc (Zn(BTZ)2), bis(10-hydroxybenzo[h]quinolinolato)beryllium (BeBq2), 8-(4-(4,6-di(naphthalene-2-yl)-1,3,5-triazin-2-yl)phenyl)quinolone (ET204), 8-hydroxyquinoline lithium (Liq), n-type metal oxides (e.g., ZnO, HfO2, etc.), or combinations thereof, but are not limited thereto. The electron transport layer may include metal oxide nanoparticles, such as zinc oxide, zinc magnesium oxide, or combinations thereof. The metal oxide nanoparticles may include Zn 1-x M x O (wherein M is Mg, Ca, Zr, W, Li, Ti, Y, Al, or a combination thereof, and 0≤x≤0.5). In the chemical formula, x may be greater than or equal to about 0.01 and less than or equal to about 0.3, for example, less than or equal to about 0.25, less than or equal to about 0.2, or less than or equal to about 0.15. The thickness of the electron transport layer may be in the range of tens to hundreds of nanometers, for example, 10-400 nanometers, preferably 20-100 nanometers. The electron transport layer may have i) a single-layer structure consisting of a single layer composed of a single substance, ii) a single-layer structure consisting of a single layer including a plurality of substances different from each other, or iii) a multilayer structure including a plurality of layers including a plurality of substances different from each other. A second electrode 400 is arranged on the second functional layer 600. The second electrode 400 is a cathode. The second electrode 400 may include Mg, Ca, Na, Ti, In, Ir, Li, Al, Ag, Zn, Pb, Ce, Ba, LiF / Al, LiO2 / Al, LiF / Ca or BaF2 / Ca, etc. In addition, an electron injection layer may also be formed between the electron transport layer and the second electrode 400.

[0082] In some embodiments, each functional layer of the light-emitting device of the present application can be prepared by the following methods: for example, spin coating, spray coating, casting, inkjet printing or LB (Langmuir-Blodgett) method and other well-known methods.

[0083] In some specific embodiments, the light-emitting layer 300 of the present application is prepared from a material dispersed with quantum dots. Specific preparation methods include photolithography, and the coating method includes spin coating or full-surface coating.

[0084] Taking a light-emitting device having RGB pixel areas as an example, as shown in FIG1 to FIG7 , the steps for preparing the light-emitting device of the present application include:

[0085] A patterned mask is placed above a first material layer including a photosensitive material (photosensitive crosslinker), and light is irradiated from above the patterned mask to expose the photosensitive material. That is, in the photosensitive material, an exposure area is formed at a position where there is no patterned mask above, and a non-exposure area is formed at a position where there is a patterned mask above. For example, the light during exposure can be i-line (wavelength 365nm), but it can also be appropriately selected according to the material. In addition, from the viewpoint of improving pattern accuracy and reducing film loss, the exposure amount is preferably 20mJ / cm 2 Furthermore, from the viewpoint of suppressing the increase in takt time and reducing damage to other components, the exposure dose is preferably 1000 mJ / cm 2 the following.

[0086] At this point, a patterned mask is placed above the green pixel region GP and the blue pixel region BP. Therefore, light irradiating the green pixel region GP and the blue pixel region BP is blocked by the patterned mask, forming non-exposed areas. Consequently, only the photosensitive material formed on the hole transport layer in the red pixel region RP is exposed, forming exposed areas. The photosensitive material in the exposed areas cross-links to form light-emitting units. Optionally, a drying process can be performed after exposure to remove the solvent that dissolved the quantum dot material.

[0087] Next, the first material layer is washed with a first solvent as a developer, and the developer is, for example, toluene or PGME, and the polarity of the first solvent is the same as that of the first luminescent material. The photosensitive material is a negative photosensitive material that is poorly soluble in the developer by exposure. Therefore, the light-emitting layer that is only the exposed photosensitive material does not dissolve in the developer, but remains on the hole transport layer. Therefore, the light-emitting layer having red quantum dots RQD is only formed on the red pixel area RP, forming a first light-emitting unit 301. Optionally, after development, a drying process can be performed again. Repeat the above steps to form a second light-emitting unit 302 having green quantum dots GQD in the green pixel area GP, and a third light-emitting unit 303 having blue quantum dots BQD in the blue pixel area BP. Thus, the structure shown in Figure 7 below is obtained. The RGB three-color pattern is only an example, and a combination of other colors can also be used.

[0088] In some embodiments, taking the example of the first light-emitting unit 301 using non-polar quantum dot material, the second light-emitting unit 302 using polar quantum dot material, and the third light-emitting unit 303 using polar quantum dot material, a first light-emitting unit 301 including non-polar quantum dot material is prepared, the first light-emitting unit 301 is located in the first pixel area, the second pixel area and the third pixel area, a coating containing polar quantum dot material is prepared on the first light-emitting unit, and a polar solvent is used for development to obtain the second light-emitting unit 302. At this time, since the first light-emitting unit 301 has been solidified, the polar solvent developer cannot dissolve the non-polar quantum dots of the first light-emitting unit 301. Subsequently, a coating containing polar quantum dot material is prepared, and a polar solvent is used for development to obtain the third light-emitting unit 303. Since the first light-emitting unit 301 and the second light-emitting unit 302 have been solidified, the polar quantum dots in the second light-emitting unit 302 are still protected.

[0089] As shown in FIG9 and FIG10 , in some embodiments, the light-emitting layer 300 can be prepared by the following method:

[0090] A first functional layer 500 is prepared on a substrate 100 having a first electrode 200; the first electrode 200 is an anode, and the first functional layer 500 includes a hole injection layer 501 and a hole transport layer 502; a first material layer containing polar red quantum dots is coated on the first functional layer 500, the thickness of the first material layer is preferably greater than 10 nm, such as the thickness of the first material layer is 15 to 50 nm, and the thickness of the first material layer is more preferably greater than 20 nm, the first material layer contains a photosensitive material, or the first material layer contains red quantum dots as a photosensitive material, and no additional photosensitive material is required; exposure is performed to form an exposed area and a non-exposed area at the location of the first material layer, a polar solvent is used as the first solvent, and the first material layer in the non-exposed area is removed to form a first light-emitting unit 301;

[0091] The same preparation method is used to prepare a second light-emitting unit 302, wherein the second light-emitting material is a non-polar quantum dot material. The second light-emitting material layer is washed with a non-polar second solvent as a developer to remove the second material layer in the non-exposed area and retain the second material layer in the exposed area, thereby forming the second light-emitting unit 302.

[0092] Repeating the above steps, a third material layer containing blue quantum dots is further coated on the substrate 100 formed with the first light-emitting unit 301 and the second light-emitting unit 302. The third material layer does not contain a photosensitive material. After coating, no exposure is performed, and the third light-emitting unit 303 is directly formed, as shown in FIG9 . Subsequently, a second functional layer 600 and a second electrode 400 are sequentially formed from bottom to top on the light-emitting layer 300. The second functional layer 600 serves as an electron transport layer, and the second electrode 400 serves as a cathode, thereby obtaining the structure shown in FIG10 . In this structure, the third light-emitting unit 303 overlaps with the orthographic projections of the first light-emitting unit 301 and the second light-emitting unit 302 on the substrate 100. The third light-emitting unit 303 located in the blue pixel region (BP) emits blue light, eliminating the need for exposure and development, thereby reducing performance loss of the blue light-emitting layer and also reducing the impact of development and elution on the luminous efficiency of the already formed first light-emitting unit 301 and the second light-emitting unit 302.

[0093] As shown in Figure 11, in some embodiments, a first functional layer 500 is prepared on a substrate 100 having a first electrode 200; the first electrode 200 is a cathode, and the first functional layer 500 is an electron transport layer; a third material layer containing polar blue quantum dots is coated on the first functional layer 500, and the thickness of the third material layer is preferably greater than 10 nm, such as the thickness of the third material layer is 15 to 50 nm, and the thickness of the third material layer is more preferably greater than 20 nm, and the third material layer does not contain a photosensitive material; the formed third material layer is not exposed to form a third light-emitting unit 303.

[0094] A first light-emitting unit 301 is prepared on the formed third material layer, where the first light-emitting material in the first material layer is a non-polar red quantum dot material. The first material layer contains a photosensitive material, or the first material layer uses red quantum dots as a photosensitive material, and no additional photosensitive material is needed. Exposure is performed to form an exposed area and a non-exposed area at the location of the first material layer, and a non-polar solvent is used as the first solvent. The first material layer in the non-exposed area is removed to form the first light-emitting unit 301.

[0095] Repeat the above steps for preparing the first light-emitting unit 301 to prepare the second light-emitting unit 302 on the substrate 100 formed with the third light-emitting unit 303 and the first light-emitting unit 301, as shown in Figure 11. Subsequently, a second functional layer 600 and a second electrode 400 are sequentially formed on the light-emitting layer 300. The second functional layer 600 includes a hole transport layer and a hole injection layer, and the second electrode 400 serves as an anode. As a result, the structure shown in Figure 11 is obtained. The third light-emitting unit 303 overlaps with the orthographic projections of the first light-emitting unit 301 and the second light-emitting unit 302 on the substrate 100. The first light-emitting unit 301 and the second light-emitting unit 302 are arranged on the upper layer of the third light-emitting unit 303. The third light-emitting unit 303 located in the blue pixel area (BP) emits blue light.

[0096] In addition, in the embodiments of the present application, the RGB three-color pattern and the production sequence are only examples, and other color combinations are also possible.

[0097] The embodiments of the present application provide an electronic device, the above-mentioned light-emitting device, or a light-emitting device obtained by the above-mentioned method for preparing the light-emitting device.

[0098] In some embodiments, the electronic device is prepared by the following method: a covering layer capable of transmitting light can be formed on the second electrode 400. Optionally, an additional substrate can be provided on top of the light-emitting device to be opposite to the substrate 100 and encapsulated. By applying the above-mentioned light-emitting device to an electronic device, an electronic device with excellent light-emitting performance can be obtained. The electronic device can be a large electronic device, such as a television, a monitor and / or an outdoor billboard. In other embodiments, the electronic device can be a small or medium-sized electronic device, such as a personal computer, a laptop computer, a personal digital terminal, a car navigation system, a game console, a smart phone, a tablet computer and / or a camera.

[0099] In order to further reduce the impact of the development process on device performance, the embodiments of the present application provide light-emitting layer materials with quantum dots of different polarities, for example, the non-polar quantum dot layer is prepared by the following method:

[0100] Red quantum dot layer: Set the parameters of 2000 rpm and 45 s to spin-coat the quantum dot solution on the hole transport layer. The red quantum dots are CdSe / ZnS quantum dots, the ligand is oleic acid, and the photosensitive crosslinker is (1E,4E)-1,5-bis(4-azido-2,3,5,6-tetrafluorophenyl)penta-1,4-dien-3-one. The quantum dots have a mass concentration of 15 mg / mL and are dissolved in toluene solution. UV exposure is 300 mj / cm 2After exposure, the film layer was developed with toluene, and after development, it was annealed at 120°C for 20 minutes to form a patterned red light quantum dot luminescent layer.

[0101] Green quantum dot layer: Set the parameters of 2000 rpm and 45 s to spin-coat the quantum dot solution on the hole transport layer. The green quantum dots are CdSe / ZnS quantum dots, the ligand is oleic acid, and the photosensitive crosslinker is (1E,4E)-1,5-bis(4-azido-2,3,5,6-tetrafluorophenyl)penta-1,4-dien-3-one. The quantum dots have a mass concentration of 15 mg / mL and are dissolved in toluene solution. The UV exposure is 300 mj / cm 2 After exposure, the film layer is developed with toluene, and after development, it is annealed at 120°C for 20 minutes to form a patterned green quantum dot light-emitting layer.

[0102] Blue quantum dot layer: Set the parameters of 2000 rpm and 45 s to spin-coat the quantum dot solution on the hole transport layer. The blue quantum dots are CdSe / ZnS structured quantum dots, the ligand is oleic acid, and the photosensitive crosslinker is (1E,4E)-1,5-bis(4-azido-2,3,5,6-tetrafluorophenyl)penta-1,4-dien-3-one. The quantum dot mass concentration is 15 mg / mL. The solution is dissolved in toluene solution and exposed to UV at 300 mj / cm 2 After exposure, the film layer is developed with toluene, and after development, it is annealed at 120 degrees for 20 minutes to form a patterned blue light quantum dot light-emitting layer.

[0103] The polar quantum dot layer was prepared by the following method:

[0104] Red quantum dot layer: Set the parameters of 2000 rpm and 45 s to spin-coat the quantum dot solution on the hole transport layer. The red quantum dots are CdSe / ZnS quantum dots, the ligand is succinic acid mono-2-(2-methyl-acryloyl)oxyethyl ester, the quantum dot mass concentration is 15 mg / mL, and the photosensitizer is ethyl 2,4,6-trimethylbenzoylphenylphosphonate, dissolved in propylene glycol monomethyl ether (PGME) solution. UV exposure is 300 mj / cm 2 After exposure, the film layer was developed using PGME, and after development, it was annealed at 120°C for 20 minutes to form a patterned red light quantum dot luminescent layer.

[0105] Green quantum dot layer: Set the parameters of 2000 rpm and 45 s to spin-coat the quantum dot solution on the hole transport layer. The green quantum dots are CdSe / ZnS quantum dots, the ligand is succinic acid mono-2-(2-methyl-acryloyl)oxyethyl ester, the quantum dot mass concentration is 15 mg / mL, and the photosensitizer is 2,4,6-trimethylbenzoylphenylphosphonic acid ethyl ester, dissolved in PGME solution. UV exposure is 300 mj / cm 2 After exposure, the film layer was developed using PGME, and after development, it was annealed at 120°C for 20 minutes to form a patterned green quantum dot light-emitting layer.

[0106] Blue quantum dot layer: Set the parameters of 2000 rpm and 45 s to spin-coat the quantum dot solution on the hole transport layer. The blue quantum dots are CdSe / ZnS quantum dots, the ligand is succinic acid mono-2-(2-methyl-acryloyl)oxyethyl ester, the quantum dot mass concentration is 15 mg / mL, and the photosensitizer is 2,4,6-trimethylbenzoylphenylphosphonic acid ethyl ester, dissolved in PGME solution. UV exposure is 300 mj / cm 2 After exposure, the film layer was developed using PGME, and after development, it was annealed at 120°C for 20 minutes to form a patterned blue light quantum dot luminescent layer.

[0107] Other functional layers can be prepared by the following methods:

[0108] Hole injection layer: The cleaned ITO glass sheets were spin-coated with PEDOT:PSS in air at a speed of 3500 r / min for 45 seconds. After spin coating, the sheets were annealed in air at a temperature of 150°C for 30 minutes. After annealing, the sheets were quickly transferred to a glove box with a nitrogen atmosphere.

[0109] Hole transport layer: A hole transport layer of 8 mg / mL TFB was spin-coated on the hole injection layer at a speed of 3000 r / min for 45 seconds. After spin coating, the layer was annealed in a glove box at a temperature of 150°C for 20 minutes.

[0110] Zinc oxide electron transport layer: spin-coat a solution of zinc oxide nanocrystals (30 mg / mL, ethanol) on the quantum dot layer at 3000 rpm for 30 s.

[0111] The other electrode can be fabricated as follows: The prepared sample wafer is placed in a vacuum chamber and the top electrode is evaporated. The deposition rate is controlled within the range of 0.2-0.4 Å / s for the first 10 nm, increasing to approximately 1.0-2.0 Å / s after 10 nm. The thickness of the prepared silver electrode is 100 nm.

[0112] The production order of the following Examples 1-2 and Comparative Example 1 is RGB. A cleaned ITO TFT substrate glass is prepared, and a light-emitting device with an ITO electrode / hole injection layer PEDOT:PSS / hole transport layer TFB / quantum dot layer / zinc oxide electron transport layer / Ag electrode structure is prepared according to the above-mentioned method.

[0113] The production order of Examples 1-2 and Comparative Example 1 is RGB:

[0114] Example 1: The following materials are selected in the process of forming the light-emitting unit: polar red quantum dot layer, PGME (quantum dot solvent, developer solvent), non-polar green quantum dot layer, toluene (quantum dot solvent, developer solvent); non-polar blue quantum dot layer, toluene (quantum dot solvent, developer solvent).

[0115] Example 2: The following materials are selected in the process of forming the light-emitting unit: polar red quantum dot layer, PGME (quantum dot solvent, developer solvent); polar green quantum dot layer, PGME (quantum dot solvent, developer solvent); non-polar blue quantum dot layer, toluene (quantum dot solvent, developer solvent).

[0116] Comparative Example 1: The following materials are selected in the process of forming the light-emitting unit: non-polar red quantum dot layer, toluene (quantum dot solvent, developer solvent); non-polar green quantum dot layer, toluene (quantum dot solvent, developer solvent); non-polar blue quantum dot layer, toluene (quantum dot solvent, developer solvent).

[0117] Table 1 shows the external quantum efficiency (EQE) performance test results for the light-emitting devices (QLEDs) of Examples 1-2 and Comparative Example 1. External quantum efficiency (EQE): A Keithley 2400 power supply was used to provide voltage input to the light-emitting element and generate a corresponding current output. The brightness of the QLEDs was measured using an integrating sphere (FOIS-1) combined with an Ocean Optics spectrometer (QE-pro). The external quantum efficiency of the light-emitting device was calculated based on the measured current density, brightness, and other parameters. A higher external quantum efficiency indicates better luminescence performance.

[0118] Table 1

[0119] From the results in Table 1, it can be seen that for the quantum dot material in the first material layer, the development process will damage the EQE, and the damage caused by the development with the same polarity solvent is greater. When the preparation process uses orthogonal solvents with different polarities, the development damage to the light-emitting unit is small. The red quantum dot material in the first material layer will undergo three solvent developments. The first development uses the corresponding solvents. The efficiency drop of Examples 1 to 2 and Comparative Example 1 is basically the same, and Comparative Example 1 is developed with three corresponding polarity solvents, and the loss is relatively large each time. From the above data, it can be seen that Example 1 is developed with the corresponding solvent for the first time and the orthogonal solvent is used for the second development. Example 2 is developed with two corresponding solvents and one orthogonal solvent. The external quantum efficiency of the red light-emitting layer of Example 1 is better.

[0120] The production sequence of Examples 3-4 and Comparative Example 2 is GRB:

[0121] Example 3: The following materials are selected in the process of forming the light-emitting unit: polar green quantum dot layer, PGME (quantum dot solvent, developer solvent), non-polar red quantum dot layer, toluene (quantum dot solvent, developer solvent); non-polar blue quantum dot layer, toluene (quantum dot solvent, developer solvent).

[0122] Example 4: The following materials are selected in the process of forming the light-emitting unit: polar green quantum dot layer, PGME (quantum dot solvent, developer solvent); polar red quantum dot layer, PGME (quantum dot solvent, developer solvent); non-polar blue quantum dot layer, toluene (quantum dot solvent, developer solvent).

[0123] Comparative Example 2: The following materials are selected in the process of forming the light-emitting unit: non-polar green quantum dot layer, toluene (quantum dot solvent, developer solvent); non-polar red quantum dot layer, toluene; non-polar blue quantum dot layer, toluene (quantum dot solvent, developer solvent).

[0124] The external quantum efficiency (EQE) performance test results of QLEDs of Examples 3 to 4 and Comparative Example 2 are shown in Table 2.

[0125] Table 2

[0126] The production order of Examples 5-6 and Comparative Example 3 is BRG:

[0127] Example 5: The following materials are selected for the light-emitting units: polar blue quantum dot layer, PGME (quantum dot solvent, developer solvent), non-polar red quantum dot layer, toluene (quantum dot solvent, developer solvent); non-polar green quantum dot layer, toluene (quantum dot solvent, developer solvent).

[0128] Example 6: The following materials are selected for the light-emitting units: polar blue quantum dot layer, PGME (quantum dot solvent, developer solvent); polar red quantum dot layer, PGME (quantum dot solvent, developer solvent); non-polar green quantum dot layer, toluene (quantum dot solvent, developer solvent).

[0129] Comparative Example 3: The following materials are selected for the light-emitting units: non-polar blue quantum dot layer, toluene (quantum dot solvent, developer solvent); non-polar red quantum dot layer, toluene (quantum dot solvent, developer solvent); non-polar green quantum dot layer, toluene (quantum dot solvent, developer solvent).

[0130] The external quantum efficiency (EQE) performance test results of QLEDs of Examples 5 to 6 and Comparative Example 3 are shown in Table 3.

[0131] Table 3

[0132] The above is a detailed introduction to a light-emitting device, preparation method and electronic device provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for technical personnel in this field, based on the ideas of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A method for preparing a light-emitting device, characterized in that: include: Providing a substrate (100) provided with a first electrode (200); forming a light-emitting layer (300) on a side of the first electrode (200) facing away from the substrate (100); The preparation of the light-emitting layer (300) includes: forming a first material layer including a first light-emitting material on the first electrode (200), forming an exposure area and a non-exposure area in the first material layer, and removing at least a portion of the exposure area or at least a portion of the first material layer in the non-exposure area by a first solvent to obtain a first light-emitting unit (301); forming a second material layer including a second light-emitting material on the first electrode (200), forming an exposure area and a non-exposure area in the second material layer, and removing at least a portion of the exposure area or at least a portion of the second material layer in the non-exposure area by a second solvent to obtain a second light-emitting unit (302); forming a second electrode (400) on the light-emitting layer (300); The first light-emitting unit (301) and the second light-emitting unit (302) are arranged along a first direction (X) of the substrate (100), the first light-emitting unit (301) is used to emit light in a first wavelength range, and the second light-emitting unit (302) is used to emit light in a second wavelength range, the first wavelength range is different from the second wavelength range, and the polarity of the second solvent is different from the polarity of the first light-emitting material.

2. The method for preparing a light emitting device according to claim 1, characterized in that: The preparation of the light-emitting layer (300) further includes: forming a third material layer including a third light-emitting material on the first electrode (200).

3. The method for preparing a light emitting device according to claim 2, characterized in that: forming an exposed area and a non-exposed area in the third material layer, and removing at least a portion of the exposed area or at least a portion of the third material layer in the non-exposed area by a third solvent to obtain a third light-emitting unit (303); The third light emitting unit (303) is used to emit light in a third wavelength range, and the third wavelength range is different from the first wavelength range and the second wavelength range; The third solvent has a polarity different from the polarity of the first light-emitting material or the polarity of the second light-emitting material.

4. The method for preparing a light emitting device according to claim 3, characterized in that: The first light emitting unit (301), the second light emitting unit (302) and the third light emitting unit (303) are arranged along a first direction (X).

5. The method for preparing a light emitting device according to claim 3, characterized in that: The first light emitting material, the second light emitting material or the third light emitting material comprises a quantum dot material.

6. The method for preparing a light emitting device according to claim 5, characterized in that: The quantum dot material includes at least one of CdSe / ZnSe, CdSe / ZnS, CdSe / ZnSe / ZnS, CdS / ZnSe, CdS / ZnS, ZnTeSe / ZnS, InP / ZnSe / ZnS and InP / ZnS.

7. The method for preparing a light emitting device according to claim 5, characterized in that: The ligand of the quantum dot material comprises at least one of alkyl carboxylic acid, alkyl phosphonic acid, alkyl phosphinic acid, alkyl thiol, alkyl amine, acrylate substituted acid, halogen, mercapto alcohol, carboxyl alcohol and amino alcohol.

8. The method for preparing a light emitting device according to claim 3, characterized in that: The first solvent, the second solvent or the third solvent includes at least one of a hydrocarbon solvent, an alkyl alcohol solvent, an ether and acetal solvent, a halogenated hydrocarbon solvent, an ester solvent and a nitrogen-containing compound solvent.

9. The method for preparing a light emitting device according to claim 3, characterized in that: The first luminescent material has a different polarity from the second solvent and the third solvent.

10. The method for preparing a light emitting device according to claim 3, characterized in that: The first material layer, the second material layer or the third material layer contains at least one of a photosensitive crosslinking agent, a photopolymerization initiator and a photoacid generator.

11. The method for preparing a light emitting device according to claim 10, characterized in that: The photosensitive crosslinking agent includes at least one of an azide compound and a free radical type photoinitiator.

12. The method for preparing a light emitting device according to claim 1, characterized in that: The substrate (100) has a plurality of isolation structures (101), and the light-emitting layer (300) is divided into a plurality of light-emitting units by the isolation structures (101).

13. The method for preparing a light emitting device according to claim 12, characterized in that: The isolation structure (101) has a first surface (110), and the material of the first surface (110) is amphiphilic.

14. The method for preparing a light emitting device according to claim 1, characterized in that: A first functional layer (500) is formed between the first electrode (200) and the light-emitting layer (300), and the first functional layer (500) includes at least one of a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, an electron transport layer, an electron blocking layer and a buffer layer.

15. The method for preparing a light emitting device according to claim 1, characterized in that: A second functional layer (600) is formed between the light-emitting layer (300) and the second electrode (400), and the second functional layer (600) includes at least one of a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, an electron transport layer, an electron blocking layer and a buffer layer.

16. The method for preparing a light emitting device according to claim 5, characterized in that: The mass percentage concentration of the quantum dot material is 1-50wt%.

17. A light emitting device, characterized in that: The light-emitting device is prepared by the preparation method according to any one of claims 1 to 16.

18. An electronic device, characterized in that: Comprising the light emitting device as claimed in claim 17.

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