Processing method for direct photoetching of quantum dots and application thereof

Abstract

The invention discloses a quantum dot direct photoetching processing method and application thereof. The processing method comprises the following steps: providing a quantum dot mother solution, and coating and volatilizing a solvent to form a photoetching quantum dot wet film; carrying out patterning illumination to obtain a photoetching film; cleaning and developing by using a developing solution to obtain a patterned quantum dot layer; wherein the quantum dot mother liquor contains quantum dots and a cross-linking agent, and the molecular structure of the cross-linking agent contains a plurality of acetophenone derivative photosensitive groups. According to the invention, a novel cross-linking agent is adopted, the quantum dots are cross-linked and the solubility is changed by utilizing an insertion reaction with surface ligands of the quantum dots, and direct patterning photoetching is realized by matching with a dissolution effect of a developing solution on non-cross-linked parts, so that a better resolution ratio can be obtained, and meanwhile, the negative influence on the characteristics of the quantum dots is extremely small; even some characteristics can generate positive influence, the optical performance of the quantum dots is well maintained or improved, and the electroluminescent performance of the quantum dot device is also remarkably improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display materials and devices, and particularly relates to a quantum dot direct lithography processing method and application thereof. BACKGROUND

[0002] Quantum dots, also known as semiconductor nanocrystals, are quasi-zero-dimensional nanomaterials with a particle size less than or close to the exciton Bohr radius. Due to the significant quantum confinement effect in three spatial dimensions, they exhibit many unique physical and chemical properties such as high luminescent efficiency, dynamic tunable luminescent wavelength, and narrow luminescent half-peak width.

[0003] Thanks to the excellent photoelectric properties of quantum dots and the low-cost characteristics of solution-based preparation and processing, display devices using quantum dots as luminescent units are considered as one of the core candidates for the next generation of display technology. The mainstream quantum dot optoelectronic display devices include two types: (1) display devices that achieve high-efficiency electroluminescence by injecting and recombining electrons and holes in quantum dot luminescent materials - quantum dot light-emitting diodes (QLED); (2) display devices that use quantum dots as light conversion materials based on their photoluminescent properties - QD-OLED or Micro LED.

[0004] The preparation of high-resolution and high-performance quantum dot pixels is the key to promoting the development of quantum dot display technology. However, although the traditional photolithography method based on photoresist can achieve excellent resolution, the performance of the prepared quantum dot pixels and display devices is severely compromised due to the etching of photoresist on quantum dots and the residual photoresist in the processing process. The methods for preparing quantum dot pixels based on inkjet printing or transfer printing also have low resolution and image distortion due to the coffee ring effect or uneven transfer pressure, respectively.

[0005] To solve the problems of traditional photolithography based on photoresist, direct photolithography has emerged. Quantum dot direct photolithography can change the solubility of quantum dots through photochemical reactions of photosensitive ligands or additives, thereby achieving photolithographic patterning; it has the advantages of simple process, high resolution, high throughput, etc. Based on this concept, the field has reported in-situ ligand exchange, ligand decomposition, ligand crosslinking, and double ligand crosslinking quantum dot direct photolithography schemes, but there are still problems such as high ultraviolet radiation dose, byproduct generation, and quantum dot performance loss. Therefore, developing new and efficient quantum dot direct photolithography systems that take into account the requirements of high resolution and high performance is an important scientific bottleneck that needs to be solved in the field.

[0006] Specifically, for example, the scientific literature

Adv. Mater. 2020, 32, 2003805

[0007] The literature

Nat. Nanotechnol. 2022, 17, 952-958

[0008] The literature

Nat. Commun. 2020, 11, 2874

[0009] Therefore, it is very urgent to develop an efficient and low-cost direct lithography processing method which does not cause obvious negative effects on the performance of the quantum dot. SUMMARY

[0010] In view of the deficiencies of the prior art, the purpose of the present application is to provide a quantum dot direct lithography processing method and its application.

[0011] To achieve the foregoing purposes of the application, the technical solutions adopted by the present application include:

[0012] In a first aspect, the present application provides a quantum dot direct lithography processing method, comprising:

[0013] providing a quantum dot mother liquor, and coating and volatilizing the solvent of the quantum dot mother liquor to form a lithography quantum dot wet film;

[0014] patterned light irradiation is performed on the lithography quantum dot wet film to cause crosslinking reaction in the irradiated part, thereby obtaining a lithography film.

[0015] washing and developing the photoresist film with a developing solution to obtain the patterned quantum dot layer;

[0016] The quantum dot mother liquor contains quantum dots and a cross-linking agent, the quantum dots have surface ligands, and the surface ligands have alkyl carbon chains, and the molecular structure of the cross-linking agent contains a plurality of phenylethanone derivative photosensitive groups.

[0017] In a second aspect, the application also provides a patterned quantum dot layer prepared by the above processing method, which contains quantum dots and a cross-linking agent, the quantum dots have surface ligands, and the surface ligands are connected to the cross-linking agent by covalent bonds generated by an insertion reaction of phenylethanone derivative photosensitive groups.

[0018] In a third aspect, the application also provides an optoelectronic device, which comprises a first electrode, a first semiconductor layer, a quantum dot functional layer, a second semiconductor layer and a second electrode arranged in sequence, wherein the first semiconductor layer and the second semiconductor layer have opposite conductive properties, and the quantum dot functional layer is the above patterned quantum dot layer.

[0019] Based on the above technical solution, compared with the prior art, the application has at least the following beneficial effects:

[0020] The processing method provided by the application uses a novel cross-linking agent, and the cross-linking agent and the surface ligands of the quantum dots are used to realize the cross-linking of the quantum dots by an insertion reaction, so that the solubility is changed, the direct patterning photoetching is realized by the dissolution of the developing solution to the uncross-linked part, a better resolution can be obtained, the negative influence on the characteristics of the quantum dots is very small, and even some characteristics are positively affected, the optical performance of the quantum dots is well maintained or improved, and the electroluminescent performance of the quantum dot device is also significantly improved.

[0021] The above description is only a summary of the technical solutions of the application, in order to enable those skilled in the art to more clearly understand the technical means of the present application, and to implement the content of the description, the following is a preferred embodiment of the application, and the detailed description is as follows. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a process schematic diagram of direct photoetching of quantum dots provided by a typical embodiment of the application;

[0023] Figure 2 is a molecular structure diagram of a cross-linking agent provided by a typical embodiment of the application;

[0024] Figure 3 is a fluorescence microscopic image of a direct photoetched quantum dot pattern provided by a typical embodiment of the application;

[0025] Figure 4a is the XPS analysis chart of quantum dot core elements before and after direct lithography of quantum dots provided by a typical embodiment of the present application;

[0026] 4b is the surface morphology image of quantum dot film before and after direct lithography of quantum dots provided by a typical embodiment of the present application;

[0027] 4c is the fluorescence emission spectrum test chart of quantum dots before and after direct lithography of quantum dots provided by a typical embodiment of the present application;

[0028] 4d is the fluorescence quantum yield comparison test chart of quantum dots before and after direct lithography of quantum dots provided by a typical embodiment of the present application;

[0029] Figure 5 is the molecular structure chart of a plurality of synthesized cross-linking agents that can be used for direct lithography of quantum dots provided by another typical embodiment of the present application;

[0030] Figure 6 is the image of red-green-blue quantum dots directly lithographed provided by a typical embodiment of the present application;

[0031] Figure 7 is the schematic diagram of the structure of an optoelectronic device based on directly lithographed quantum dots provided by a typical embodiment of the present application;

[0032] Figure 8 is the test chart of external quantum efficiency of the optoelectronic device under different current densities provided by a typical embodiment of the present application;

[0033] Figure 9 is the microscopic image of high-resolution quantum dot light-emitting devices of different colors provided by a typical embodiment of the present application;

[0034] Figure 10 is the fluorescence microscopic image of lithography patterns under the same conditions of the typical embodiment and the comparative example of the present application. DETAILED DESCRIPTION

[0035] In view of the deficiencies in the prior art, the present inventors have long studied and practiced to come up with the technical solution of the present application. The technical solution, its implementation process and principles will be further explained as follows.

[0036] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, however, the present application can also be implemented in other ways different from those described herein, therefore, the protection scope of the present application is not limited by the specific embodiments disclosed below.

[0037] Moreover, the terms such as "first" and "second" and the like are merely used to distinguish one component or method step from another component or method step having the same name, and do not necessarily require or imply any such actual relationship or order between such components or method steps.

[0038] As described above, although the photoresist-based quantum dot pixelization method can achieve excellent resolution, the prepared quantum dot pixels and display devices have serious performance loss due to the etching of photoresist to quantum dots and photoresist residues in the processing process. The methods for preparing quantum dot pixels based on inkjet printing or transfer printing respectively have problems such as low resolution and image distortion due to coffee ring effect or uneven transfer pressure.

[0039] The existing quantum dot direct lithography strategies, such as in-situ ligand exchange, ligand decomposition, ligand cross-linking, double ligand cross-linking, etc., still generally have problems such as high ultraviolet radiation dose, by-product generation, and quantum dot performance loss.

[0040] Therefore, the purpose of the present application and the primary technical problem to be solved are to develop a new type of efficient cross-linking agent, taking into account the high resolution and high performance requirements of quantum dot patterning, and to promote its application in the field of high-resolution display.

[0041] In view of the deficiencies of the prior art, referring to Figure 1 The present application develops a new strategy for quantum dot direct lithography: the present application introduces a highly photosensitive active group of phenylethanone derivative as a photosensitive group, and designs and synthesizes a corresponding high-performance cross-linking agent. The cross-linking agent can undergo an insertion reaction with the surface ligand of the quantum dots under ultraviolet exposure conditions, causing the quantum dots to cross-link, thereby reducing the solubility of the quantum dots. Based on this, high-resolution quantum dot patterns can be prepared by means of regional exposure. Further, corresponding optoelectronic display devices can be prepared.

[0042] Based on the above purpose, the embodiment of the present application provides a processing method for quantum dot direct lithography, which comprises:

[0043] A quantum dot mother liquor is provided, and the quantum dot mother liquor is coated and the solvent is volatilized to form a lithographic quantum dot wet film;

[0044] The lithographic quantum dot wet film is subjected to patterned irradiation to cause cross-linking reaction in the irradiated part, and a lithographic thin film is obtained;

[0045] The lithographic thin film is cleaned and developed with a developing solution to obtain a patterned quantum dot layer;

[0046] The quantum dot mother liquor contains quantum dots and a crosslinking agent, the surface of the quantum dots has a surface ligand, the surface ligand has an alkyl carbon chain, and the molecular structure of the crosslinking agent contains a plurality of phenylethanone derivative photosensitive groups.

[0047] In some embodiments, the molecular structure of the crosslinking agent includes a first phenylethanone derivative group, an intermediate group, and a second phenylethanone derivative group, and the first and second phenylethanone derivative groups are respectively connected to the intermediate group by a covalent bond.

[0048] In addition, regarding the surface ligand, it can be any one of oleic acid, thiol, oleylamine molecules, but is not limited thereto, and the surface ligand allows other functional groups (such as sulfonic acid groups, phosphine oxide groups, phosphine groups, etc.), but in order to be able to undergo an insertion reaction, the surface ligand needs to contain an alkyl chain.

[0049] The phenylethanone derivative group can undergo an insertion reaction with the alkyl chain in the organic ligand on the surface of the quantum dot under ultraviolet exposure at a suitable wavelength, thereby achieving crosslinking of the quantum dots.

[0050] In some embodiments, the crosslinking agent includes:

[0051]

[0052] any one or a combination of two or more thereof;

[0053] wherein R1, R2, R3, R4 groups are independently selected from any one of H or C1-C6 alkyl (i.e., in a certain molecular structure, R1, R2, R3, R4 can be the same or different); R5, R6 groups are independently selected from any one of C1-C24 saturated alkyl, C1-C24 unsaturated alkyl containing C=C double bond, C6-C24 aryl, C7-C24 hydrocarbon group containing both aromatic ring and alkane.

[0054] In some embodiments, the surface ligand includes any one or a combination of two or more of R-COOH, R-SH, R-NH2, R-SO3H, R3-P=0, R3-P; wherein the R group is any one of C1-C24 saturated alkyl, C1-C24 unsaturated alkyl containing C=C double bond, C7-C24 hydrocarbon group containing both aromatic ring and alkane.

[0055] As some typical examples of the above technical solutions, the general process of the processing method provided by the present application is as follows: the above photosensitive crosslinking agent and quantum dots are dissolved in a corresponding organic solvent to configure a quantum dot mother liquor capable of direct photolithography. Subsequently, the direct photolithography mother liquor is coated on a substrate by means of solution processing such as spin coating, blade coating, slot coating or inkjet printing, and a photolithography quantum dot wet film is formed after the solvent is volatilized. The photolithography quantum dot wet film is exposed by using a photomask plate or a laser direct writing technology. The exposed photolithography quantum dot wet film is soaked or washed by using a developing solution, and the unexposed area is washed away, so as to form a photolithography quantum dot dry film.

[0056] As to the specific processing conditions and specific details, in some embodiments, the concentration of quantum dots in the quantum dot mother liquor is 1 mg / mL-100 mg / mL.

[0057] In some embodiments, the added amount of the crosslinking agent in the quantum dot mother liquor is 0.1%-100% of the mass of the quantum dots.

[0058] In some embodiments, the thickness of the photolithography quantum dot wet film is 5 nm-2000 nm.

[0059] In some embodiments, the solvent includes any one or a mixture of multiple of petroleum ether, n-hexane, n-octane, toluene, chlorobenzene and xylene.

[0060] In some embodiments, the developing solution includes any one or a mixture of multiple of petroleum ether, n-hexane, n-octane, toluene, chlorobenzene and xylene.

[0061] In some embodiments, the quantum dots include Cd-based quantum dots and / or InP quantum dots of different colors, but are not limited thereto.

[0062] In some embodiments, the wavelength of the patterned light is 200-300 nm. Preferably, it is a common commercial ultraviolet wavelength of 254 nm.

[0063] In some embodiments, the resolution of the patterned light can reach 1.1 μm.

[0064] The present application also provides a patterned quantum dot layer prepared by the above processing method, which includes quantum dots and a crosslinking agent, the quantum dots have a surface ligand, and the surface ligand is connected to the crosslinking agent by a covalent bond generated by an insertion reaction of a phenyl ethanone derivative photosensitive group.

[0065] The embodiment of the present application also provides further application of the above technical scheme, namely, an optoelectronic device, comprising a first electrode, a first semiconductor layer, a quantum dot functional layer, a second semiconductor layer and a second electrode which are sequentially stacked, wherein the first semiconductor layer and the second semiconductor layer have opposite conductive properties, and the quantum dot functional layer is the above-mentioned patterned quantum dot layer.

[0066] In some embodiments, the substrate for making the device can include a conductive transparent glass electrode (for example, ITO glass, FTO glass, etc.), a transparent flexible conductive electrode (for example, ITO-PET), glass, a silicon wafer, a potassium bromide wafer, etc. The substrate can be pre-coated with functional materials to achieve specific functions (for example, in the process of preparing a quantum dot light emitting diode (QLED), a photolithographic quantum dot film is coated on an electrode pre-coated with a first semiconductor layer).

[0067] As a typical example, the present application provides an optoelectronic device directly photolithographic quantum dots and its high-resolution display application, which is characterized by comprising electrodes on both sides, a first semiconductor layer and a second semiconductor layer (having opposite conductive properties), and a directly photolithographic quantum dot layer existing between the first semiconductor layer and the second semiconductor layer.

[0068] Specifically, the material of the optional first semiconductor layer includes one or more of PEDOT:PSS, PF8Cz, TFB, PVK, Poly-TPD, tungsten oxide, molybdenum oxide, nickel oxide, etc., and is not limited thereto. The optional second semiconductor layer includes one or more of zinc oxide (ZnO), magnesium-doped zinc oxide (ZMO), and tin oxide (SnO2), and is not limited thereto; the electrodes on both sides are one of ITO glass electrodes, FTO glass electrodes or flexible ITO-PET electrodes, and one of Al, Ag, Au metal electrodes, and are also not limited thereto.

[0069] The directly photolithographic quantum dot device formed by the technical scheme provided by the present application has good maintenance in electroluminescent performance (for example, light spectrum, brightness, etc.), and even has a certain degree of positive improvement (for example, positive improvement of external quantum dot efficiency); using a patterned photomask or laser direct technology, the quantum dots are prepared into a high-precision pattern, which can realize a high-resolution display device and display high-precision information.

[0070] Based on the above quantum dot direct lithography scheme, the application realizes excellent quantum dot patterning resolution (line width: ~1.1 microns); compared with the un-lithographed quantum dot dry film, the optical performance (such as fluorescence intensity, fluorescence peak position and half-peak width, fluorescence quantum yield, fluorescence lifetime, etc.) of the quantum dot dry film subjected to direct lithography using the scheme proposed by the application is well maintained, for example, the fluorescence quantum yield maintenance rate reaches 100%; compared with the optoelectronic device prepared using the un-lithographed quantum dot dry film, the electroluminescent performance (such as luminescence spectrum, brightness, etc.) of the optoelectronic device prepared using the quantum dot dry film obtained by the direct lithography processing method of the application is well maintained, for example, the external quantum efficiency of the device reaches 20.3%, which is at the industry leading level; based on the direct lithography quantum dot dry film, high-resolution optoelectronic devices (pixel size <5 microns) are successfully realized, which shows the application potential of the application in the high-resolution display field.

[0071] The technical solutions of the application are further described in detail below through several embodiments in combination with the drawings. However, the selected embodiments are only used to illustrate the application, and do not limit the scope of the application.

[0072] Embodiment 1

[0073] This embodiment illustrates a direct lithography method of CdSe / ZnS core-shell quantum dots, as shown below.

[0074] First, a crosslinking agent (named PC-1) as shown in Figure 2 The related organic synthesis route and method can be implemented according to the existing organic synthesis design rules and technical means, and this embodiment will not be described again;

[0075] Subsequently, PC-1 is mixed with commercially available CdSe / ZnS core-shell red quantum dots (the surface ligand is one or more of oleylamine, oleic acid, dodecanethiol) and dispersed in n-octane solvent to prepare a direct lithography quantum dot mother liquor. The concentration of the quantum dots is 20 mg / mL. The addition amount of the crosslinking agent (PC-1) is 10 wt% of the quantum dots;

[0076] Then, the direct lithography quantum dot mother liquor is coated on the surface of a silicon wafer by spin coating to prepare a quantum dot wet film to be lithographed. No drying or other post-processing operation is required in this process. The prepared wet film has a thickness of 30 nm.

[0077] Local exposure is performed using 254 nm ultraviolet light combined with a patterned photomask. The energy density of the used ultraviolet light source is 10 mW / cm 2 , and the exposure time is 20 s (exposure dose is 200 mJ / cm 2), and using n-octane as a developer to wash away the unexposed quantum dots, a high-resolution quantum dot dry film or pattern can be obtained. The resolution of the pattern can reach 1.1 microns, as shown in Figure 3 .

[0078] Through testing, the structure and optical performance of the quantum dots of the quantum dot dry film obtained by direct lithography have almost no degradation compared to the quantum dot dry film without lithography. The specific test results are shown in Figures 4a-4d . Specifically, the XPS test results Figure 4a show that the valence states of the core elements of the quantum dots have no significant change. At the same time, the surface roughness of the quantum dot film is also well maintained after direct lithography Figure 4b . In terms of optical performance, the fluorescence peak position (624 nm) and half-peak width (20 nm) of the directly lithographed quantum dots are well maintained Figure 4c . In particular, the fluorescence quantum yield of the quantum dot film before and after direct lithography is 64.4%, with a maintenance rate of 100% Figure 4d . As a comparison, the fluorescence quantum yield of the quantum dot film without cross-linking agent (PC-1) is degraded to 59.6% after UV exposure. The above phenomena show that the introduction of the cross-linking agent effectively avoids the photodamage of the quantum dots under UV exposure, thereby achieving the ideal non-destructive lithography effect of the quantum dots.

[0079] Example 2

[0080] In this example, different cross-linking agents (such as many compounds shown in Figure 5 ) are used to repeat steps (2)-(4) in Example 1, and high-resolution quantum dot patterns can be obtained.

[0081] Example 3

[0082] In this example, different quantum dots (including but not limited to commercially available CdSe / ZnS core-shell green quantum dots and CdZnSe / ZnSe / ZnS core-shell blue quantum dots) are used to repeat the steps of preparation-coating-exposure-development of the quantum dot mother liquor in Example 1, and high-resolution quantum dot patterns of different colors can be obtained (specific results are shown in Figure 6 .

[0083] Example 4

[0084] This example presents the preparation process of an optoelectronic device based on directly lithographed quantum dots, as shown below:

[0085] A photoelectric device was prepared using ITO glass as the anode, spin-coated PEDOT:PSS as the hole injection layer, spin-coated TFB as the hole transport layer, the directly photolithographic CdSe / ZnS core-shell red light quantum dots provided in Example 1 as the emission layer, spin-coated ZnO nanoparticles as the electron transport layer, and evaporated Ag electrode as the cathode. The device structure is shown in FIG. Figure 6 shown.

[0086] Figure 8 The device performance test results shown in the figure show that compared with the optoelectronic devices prepared using the unlithographic quantum dot dry film, the optoelectronic performance (including luminescence spectrum, brightness, etc.) of the optoelectronic devices prepared using the directly photolithographic quantum dot dry film was well maintained. For example, the maximum external quantum efficiency of the device reached 20.3%, which is the industry-leading level. In contrast, the maximum external quantum efficiency of the optoelectronic device prepared based on the quantum dot film without crosslinking agent (PC-1) declined to 18.3% after UV exposure. The above phenomenon shows that the introduction of the crosslinker effectively avoids the photodamage of the quantum dots under UV exposure and achieves a positive improvement in the electroluminescent performance of the quantum dots.

[0087] In the exposure step, a patterned photomask is used for local exposure to achieve high-resolution display. The size of a single pixel unit can be controlled within 5 microns. In addition, in the preparation process of the optoelectronic device of this embodiment, different quantum dots used in Example 3 can be used to obtain high-resolution quantum dot light-emitting devices of different colors, as shown in FIG. Figure 9 As shown, these devices all have excellent photoelectric conversion performance.

[0088] Comparative Example 1

[0089] This comparative example is substantially the same as Example 1, the main difference being the cross-linking agent, as shown below.

[0090] Some existing technologies disclose technical solutions for direct quantum dot lithography using benzophenone derivatives, which is equivalent to the R1 and R2 groups in the present invention being benzene rings. However, due to the differences in the photosensitive groups, there are obvious differences in the photoresponsive activity and photoresponsive wavelength, which ultimately lead to different quantum dot lithography results.

[0091] This comparative example conducted a control experiment, replacing the R1 and R2 groups in the molecular structure of Example 1 with benzene rings (referred to as BP-1) by H, and performing direct photolithography under the same conditions. The test results show that due to the relatively poor compatibility of the photosensitive group of BP-1 with the quantum dot film, it is difficult for it to be evenly dispersed with the quantum dots to form a high-quality film, resulting in the crosslinking agent being difficult to fully exert its efficacy. Therefore, under the same photolithography conditions, the uniformity of the prepared quantum dot pixel array is poor, and the fluorescence intensity is lower, as shown in FIG. Figure 10 shown.

[0092] Based on the above embodiments, it can be clear that the processing method provided by the embodiments of the present application adopts a novel crosslinking agent, uses the insertion reaction of the crosslinking agent with the surface ligand of the quantum dots to crosslink the quantum dots, changes the solubility, cooperates with the dissolution of the uncrosslinked part by the developing solution to realize direct patterning photolithography, can obtain better resolution, and has little negative impact on the characteristics of the quantum dots, even some characteristics have positive impact, the optical performance of the quantum dots is well maintained or improved, and the electroluminescent performance of the quantum dot device is also significantly improved.

[0093] It should be understood that the above embodiments are only for illustrating the technical concepts and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and to implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made in accordance with the spirit and essence of the present application shall be covered within the protection scope of the present application.

Claims

1. A method for processing quantum dots by direct photolithography, comprising: Providing a quantum dot mother solution, and coating the quantum dot mother solution and volatilizing the solvent to form a photolithography quantum dot wet film; performing patterned light irradiation on the photolithography quantum dot wet film so as to cause a cross-linking reaction to occur in the irradiated portion thereof, thereby obtaining a photolithography thin film; Cleaning and developing the photoresist film with a developer to obtain a patterned quantum dot layer; The invention is characterized in that the quantum dot mother solution contains quantum dots and a cross-linking agent, the surface of the quantum dots has a surface ligand, the surface ligand has an alkyl carbon chain, and the molecular structure of the cross-linking agent contains multiple acetophenone derivative photosensitive groups.

2. The processing method according to claim 1, characterized in that: The molecular structure of the cross-linking agent includes a first acetophenone derivative group, an intermediate group and a second acetophenone derivative group. The first acetophenone derivative group and the second acetophenone derivative group are respectively connected to the intermediate group through a covalent bond.

3. The processing method according to claim 2, characterized in that: The cross-linking agent includes: Any one or a combination of two or more; Among them, the R1, R2, R3, and R4 groups are independently selected from any one of H or C1-C6 alkyl groups; the R5 and R6 groups are independently selected from any one of C1-C24 saturated alkyl groups, C1-C24 unsaturated alkyl groups containing C=C double bonds, C6-C24 aromatic groups, and C7-C24 hydrocarbon groups containing both aromatic rings and alkanes.

4. The processing method according to claim 1, characterized in that: The quantum dot surface ligands include any one of R-COOH, R-SH, R-NH2, R-SO3H, R3-P=O, R3-P or a combination of two or more thereof; wherein the R group is any one of a saturated alkyl group of C1-C24, an unsaturated alkyl group containing a C=C double bond between C1-C24, and a hydrocarbon group between C7-C24 containing both aromatic rings and alkanes.

5. The processing method according to claim 1, characterized in that: The quantum dot concentration in the quantum dot mother solution is 1 mg / mL-100 mg / mL; And / or, the amount of the cross-linking agent added to the quantum dot mother solution is 0.1%-100% of the mass of the quantum dots.

6. The processing method according to claim 1, characterized in that: The thickness of the photolithography quantum dot wet film is 5nm-2000nm.

7. The processing method according to claim 1, characterized in that: The solvent includes any one or more mixtures of petroleum ether, n-hexane, n-octane, toluene, chlorobenzene, and xylene; And / or, the developer includes any one or more mixtures of petroleum ether, n-hexane, n-octane, toluene, chlorobenzene, and xylene.

8. The processing method according to claim 1, characterized in that: The wavelength of the patterned light is 200-300 nm; And / or, the resolution of the patterned illumination can reach 1.1 μm.

9. The patterned quantum dot layer obtained by the processing method according to any one of claims 1 to 8, characterized in that: The invention comprises quantum dots and a cross-linking agent. The quantum dots have surface ligands. The surface ligands are connected to the cross-linking agent through a covalent bond generated by an insertion reaction of a photosensitive group of an acetophenone derivative.

10. A photoelectric device, characterized in that: It comprises a first electrode, a first semiconductor layer, a quantum dot functional layer, a second semiconductor layer and a second electrode stacked in sequence, wherein the first semiconductor layer and the second semiconductor layer have opposite conductive properties, and the quantum dot functional layer is the patterned quantum dot layer according to claim 9.

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