POSS (Polyhedral Oligomeric Silsesquioxane) connection-based quantum dot photoresist composite material and preparation method and application thereof

Abstract

The invention discloses a quantum dot photoresist composite material based on POSS (Polyhedral Oligomeric Silsesquioxane) connection as well as a preparation method and application of the quantum dot photoresist composite material. The quantum dot photoresist composite material comprises a plurality of POSS (Polyhedral Oligomeric Silsesquioxane)-quantum dot complexes, the POSS-quantum dot complex comprises a bridging structure formed by connecting a POSS structural monomer and quantum dots through covalent bonds or coordinate bonds, wherein the quantum dots are uniformly embedded into a framework of the POSS structural monomer; the composite main body network framework is formed by combining a POSS structural monomer and a resin monomer, or the composite main body network framework is formed by combining the POSS structural monomer and the resin monomer, the quantum dots are uniformly embedded in the composite main body network framework, and the three parts form a ternary hybrid network, or the quantum dots are directly mixed in the composite main body network framework in a dispersed form. According to the quantum dot photoresist composite material, migration, agglomeration and phase separation of quantum dots can be reduced, and the edge resolution and resolution of patterns are improved, so that micron and even submicron three-color pixel-level patterning is realized.

Description

TECHNICAL FIELD

[0001] The application relates to a quantum dot photoresist composite material, in particular to a quantum dot photoresist composite material based on POSS connection and a preparation method thereof, and application in Micro-LED micro display, and belongs to the technical field of optoelectronic display materials. BACKGROUND

[0002] Micro-LED is a new generation of display technology, and has the advantages of high brightness, high contrast and high response speed, and is an ideal solution for AR / VR and high-end display. However, to realize the monolithic integration full-color display of Micro-LED, one of the keys is to accurately pattern the red, green and blue quantum dots to the micro-pixel area to form a high-resolution light-emitting pattern.

[0003] At present, the commonly used quantum dot photoresist (QD-PR) usually adopts the way of physically dispersing quantum dots in photoresist resin, but this way has the following problems: 1. Lack of chemical fixation of quantum dots, resulting in poor thermal stability; 2. The resolution of the photoresist pattern is limited by factors such as quantum dot agglomeration and refractive index mismatch.

[0004] Therefore, it is urgent to develop a new composite material system that can simultaneously enhance the binding ability between quantum dots and photoresist networks, improve stability and pattern shape retention. SUMMARY

[0005] The main purpose of the present application is to provide a quantum dot photoresist composite material connected by functionalized POSS structural units and a preparation method thereof to overcome the shortcomings of the prior art.

[0006] Another purpose of the present application is to provide the application of the quantum dot photoresist composite material based on POSS connection.

[0007] To achieve the above purposes, the application adopts the following technical solutions: The first aspect of the embodiment of the present application provides a quantum dot photoresist composite material based on POSS connection, which comprises a plurality of POSS-quantum dot composite bodies; the POSS-quantum dot composite body comprises a bridged structure formed by covalent bond or coordination bond between a POSS structural monomer and a quantum dot, the quantum dots are uniformly embedded in the backbone of the POSS structural monomer and form a three-dimensional network structure, and a dense coating layer is formed on the surface of the quantum dots.

[0008] The second aspect of the embodiment of the present application further provides a preparation method of the quantum dot photoresist composite material based on POSS connection, which comprises: The quantum dots are connected with the POSS structure monomer through a covalent bond or a coordination bond to form a POSS-quantum dot complex; The POSS-quantum dot complex is mixed, or the POSS-quantum dot complex is mixed with a photoresist system to obtain a POSS connection-based quantum dot photoresist composite material.

[0009] The third aspect of the embodiment of the present application further provides another POSS connection-based quantum dot photoresist composite material, which comprises a composite host network framework formed by combining a POSS structure monomer with a resin monomer, and quantum dots, the quantum dots are uniformly embedded inside the composite host network framework to form a ternary hybrid network, wherein the POSS structure monomer is connected with the quantum dots through a covalent bond or a coordination bond, and a dense coating layer is formed on the surface of the quantum dots.

[0010] The fourth aspect of the embodiment of the present application further provides a preparation method of the POSS connection-based quantum dot photoresist composite material, which comprises uniformly mixing a POSS structure monomer, quantum dots, a resin monomer, a photoinitiator and a solvent to obtain the POSS connection-based quantum dot photoresist composite material. The fifth aspect of the embodiment of the present application further provides another POSS connection-based quantum dot photoresist composite material, which comprises a composite host network framework formed by combining a POSS structure monomer with a resin monomer, and quantum dots, the quantum dots are directly mixed in a dispersed form between the composite host network framework.

[0011] The sixth aspect of the embodiment of the present application further provides a preparation method of the POSS connection-based quantum dot photoresist composite material, which comprises first combining a POSS structure monomer with a resin monomer to form a composite host network framework, and then directly mixing quantum dots in a dispersed form between the composite host network framework to obtain the POSS connection-based quantum dot photoresist composite material.

[0012] The seventh aspect of the embodiment of the present application further provides an application of the POSS connection-based quantum dot photoresist composite material in Micro-LED full-color display.

[0013] Correspondingly, the eighth aspect of the embodiment of the present application further provides a quantum dot patterning method, which comprises: The POSS connection-based quantum dot photoresist composite material is applied to the surface of a Micro-LED chip; The patterning exposure is performed in a manner of mask exposure, laser scanning or TPP; After development, a patterned quantum dot pattern of a corresponding color is obtained.

[0014] Compared with the prior art, the present application has the following beneficial effects: 1) The quantum dot photoresist composite material based on POSS connection provided by the application forms covalent or coordination connection between quantum dots and functionalized POSS structure monomers, the cage-shaped inorganic framework of POSS has high thermal stability and steric hindrance effect, and can form stable three-dimensional microstructure in the polymer network after the glue is cured, so that the quantum dots are uniformly fixed in the crosslinked matrix, the migration, agglomeration and phase separation of the quantum dots are reduced, the edge resolution and resolution of the pattern are improved, so that micron or even sub-micron three-color pixel-level patterning is realized, and the structural stability under the aging condition during the patterning process is improved; 2) Since the surface of the quantum dots is constructed with a surface coating layer, the coating layer can effectively inhibit the ligand desorption of the quantum dots under heating, light and chemical environment (solvent), reduce the generation of surface defects, thereby improving the light-emitting efficiency of the quantum dots and maintaining the long-term light stability, including the anti-blue light bleaching ability and high heat resistance; 3) In the quantum dot photoresist composite material based on POSS connection provided by the application, the functionalized POSS structure monomer is used as a chemical bridge to fix the quantum dots, and is used to form a covalent network with the resin monomer to enhance the mechanical stability of the whole, and the double anchoring effect makes the quantum dots uniformly distributed in the composite main network framework, thereby improving the micron / sub-micron patterning precision; 4) In the quantum dot photoresist composite material based on POSS connection provided by the application, the quantum dots are more uniformly distributed, the patterned light-emitting is more stable, the color saturation and uniformity are better than those of the prior art, the photoetching can be accurately patterned, by adjusting different POSS-quantum dot composites, high-resolution full-color patterning of independent three-color channels can be realized on a Micro-LED single chip, which is suitable for Micro-LED pixel-level full-color integration, and has higher functionality and applicability in actual application; 5) The quantum dot photoresist composite material based on POSS connection provided by the application is resistant to high temperature and aging, and is suitable for Micro-LED packaging and working environment. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0016] Figure 1 is the photoetching result diagram of the photoresist material in Comparative Example 1; Figure 2 is the photoetching result diagram of the quantum dot photoresist composite material based on POSS connection prepared in Example 1; Figure 3 is a photolithography result map of the POSS-linking based quantum dot photoresist composite material prepared in Example 10; Figure 4 is a photolithography result map of the POSS-linking based quantum dot photoresist composite material prepared in Example 21; Figure 5 is a photolithography result map of the QDs dissolution scheme in Example 26. DETAILED DESCRIPTION

[0017] In view of the deficiencies of the prior art, the present inventors have long studied and practiced and finally proposed the technical solution of the present application, which mainly provides a composite material of quantum dots and photoresist resin connected by functionalized POSS structural units, which is suitable for monolithic integrated full-color patterning of Micro-LED micro display.

[0018] The technical solution, its implementation process and principles will be further explained as follows. However, it should be understood that the above technical features of the present application and the technical features specifically described in the following (Examples) can be combined with each other to form new or preferred technical solutions within the scope of the present application. Due to the limited space, they will not be listed one by one here.

[0019] As an aspect of the technical solution of the present application, a POSS-linking based quantum dot photoresist composite material includes a plurality of POSS-quantum dot composite bodies; the POSS-quantum dot composite body includes a bridging structure formed by covalent bond or coordination bond between a POSS structural monomer and a quantum dot, the quantum dots are uniformly embedded in the backbone of the POSS structural monomer and form a three-dimensional network structure, and a dense coating layer is formed on the surface of the quantum dots.

[0020] In some embodiments, the POSS-linking based quantum dot photoresist composite material includes a plurality of the POSS-quantum dot composite bodies cross-linked with each other.

[0021] In other embodiments, the POSS-linking based quantum dot photoresist composite material further includes a photoresist matrix, and the plurality of POSS-quantum dot composite bodies are uniformly dispersed in the photoresist matrix.

[0022] In some embodiments, the POSS-quantum dot complex is formed by a functionalized POSS building block with at least one end having a first functional group as a ligand group for bonding to the surface of a quantum dot, and a quantum dot surface metal ion or group substitution by coordination bonding. The first functional group can include one or more of a combination of a thiol group, a carboxyl group, an amino group, a phosphonic acid group, a phosphine oxide group, a selenol group, an acrylate group, an epoxy group, and the like, but not limited thereto. As long as the above functional groups are introduced to the POSS building block, bonding to the surface of the quantum dot can be achieved.

[0023] In some more specific embodiments, taking the case of a carboxyl group as the first functional group, the functionalized POSS building block is obtained by carboxyl (-COOH) modification. The specific modification method can be: an amide / salt reaction between an aminopropyl-POSS (POSS-NH2) and a tricarboxylic acid substance (such as 3-aminopropane-1,1,3-tricarboxylic acid), or acylation or esterification of the end group of the POSS by acryloyl chloride, succinic anhydride, etc. The mechanism of action of the carboxyl-modified POSS building block is as follows: first, the oxygen atom in the carboxyl group has a lone pair of electrons, which can form a coordination bond with the Cd 2+ , Zn 2+ , In 3+ on the surface of the quantum dot. Specifically, the carboxyl group is bonded to the metal site on the surface of the quantum dot by bidentate or monodentate coordination; second, the carboxyl group can replace the thiol / amine ligand, reducing defects and improving the fluorescence quantum yield; third, the polarity of the carboxyl group increases the solvent dispersibility and resin compatibility of the POSS building block. The advantages are: not only has strong coordination force, but also can repair surface vacancy defects of the quantum dot, can form a multi-point adsorption and coating layer, and can enhance the chemical stability of the quantum dot.

[0024] By introducing a plurality of carboxyl active groups into the cage-like silsesquioxane (POSS) structure, the modified POSS building block obtained can form stable coordination bonds or chemical bonds with the metal atoms on the surface of the quantum dot, and a dense surface coating layer is constructed. The coating layer can effectively inhibit the desorption of ligands from the quantum dot under the conditions of solvent, heating and light, reduce the generation of surface defects, thereby improving the luminescence efficiency of the quantum dot and maintaining its long-term light stability.

[0025] Moreover, the carboxyl group contained in the modified POSS building block has a certain polarity, which can improve the dispersibility of the quantum dot in the organic phase, significantly reduce the risk of agglomeration and sedimentation, and improve the uniformity and storage stability of the glue system. The coordination of the carboxyl group with the surface of the quantum dot can reduce the non-radiative recombination path, which is conducive to maintaining a high quantum yield.

[0026] In addition, the cage-like inorganic framework of the POSS structure monomer has high thermal stability and steric hindrance effect, and can form a stable three-dimensional microstructure in the polymer network after the glue is cured, so that the quantum dots are uniformly fixed in the cross-linked matrix, migration, aggregation and phase separation are inhibited, and the structural stability in the patterning process and under aging conditions is improved. The present application thus realizes the comprehensive improvement of the dispersion, heat resistance and photolithographic patterning performance of quantum dots.

[0027] In some more specific embodiments, taking the scheme of the first functional group being a mercapto group as an example, the functionalized POSS structure monomer is obtained by mercapto (-SH) modification, and the specific modification method can be: grafting mercapto silane (such as MPTMS) to the end of POSS, or introducing mercapto after ring opening of POSS crotonate. The mechanism of mercapto-modified POSS structure monomer is that -SH forms S-M covalent coordination with the metal oxide ions (such as Cd 2+ , Zn 2+ , In 3+ ) on the surface of the quantum dots, has high bond energy (stronger than -COOH coordination), forms a POSS-S-metal coordination structure, can replace the traditional small molecule mercapto ligand, forms a more stable "multi-point anchoring" structure and a strong bonding shell, and improves the thermal stability.

[0028] In some more specific embodiments, taking the scheme of the first functional group being an amino group as an example, the functionalized POSS structure monomer is obtained by amino (-NH2) modification, and the specific modification method can be: introducing a polyamine structure (such as ethylenediamine, triethylenetetramine) by aminolysis reaction, or directly using a commercial amino-POSS structure monomer. The mechanism of amino-modified POSS structure monomer is that amino forms coordination with Zn 2+ , Cd 2+ on the surface of the quantum dots, and can further undergo ring opening reaction (such as with epoxy monomer) with the photoresist resin, providing double reactive activity.

[0029] In some more specific embodiments, taking the scheme of the first functional group being a phosphonic acid group as an example, it is suitable for the shell of CdSe / ZnS and InP / ZnS, and the coordination mechanism is to form bidentate coordination, which has strong surface passivation effect and can inhibit non-radiative recombination.

[0030] In other embodiments, the POSS-quantum dot complex is formed by connecting the functionalized POSS structure monomer and the quantum dots with the first pre-modified ligand through coordination bond, and the first pre-modified ligand can contain one or a combination of phosphonic acid group, mercapto group, selenol group, carboxyl group, acrylate group, epoxy group, but is not limited thereto. These ligands can be matched with the functionalized POSS structure monomer to realize precise regulation of the length of the bridging chain.

[0031] In other more preferred embodiments, in order to better adapt the quantum dots to the photoresist system, the surface of the quantum dots can also have a second pre-modified ligand as an active end group, for example, the second pre-modified ligand can include one or more of a combination of acrylic ligands, methacrylic ligands (UV-curable), epoxy ligands (reactable with epoxy resin), isocyanate ligands, thiol ligands, amino ligands (usable for grafting), etc., but not limited to this.

[0032] Further, at least one end of the functionalized POSS structure monomer also has a second functional group matching the second pre-modified ligand, which can include one or more of a combination of acrylate groups, methacrylic ester groups, epoxy groups, amino groups, thiol groups, etc., but not limited to this. Among them, the acrylate groups, methacrylic ester groups, etc. can participate in free radical polymerization together with the ligands with C=C on the surface of the quantum dots to form a copolymer network, and the quantum dots are uniformly locked in the skeleton. The epoxy group can undergo ring-opening addition with the carboxyl or hydroxyl ligand on the surface of the quantum dots. The amino, thiol, etc. can undergo nucleophilic attack with the epoxy, isocyanate, etc. groups on the surface of the quantum dots to form a covalent bridge.

[0033] In some embodiments, at least one end of the functionalized POSS structure monomer also has a third functional group as a photopolymerization active group capable of participating in photopolymerization, which can improve the resin binding ability and enhance the network crosslinking. Specifically, the third functional group is a functional group capable of absorbing light energy and producing active species or undergoing structural changes under light conditions, which can include one or more of a combination of α-carbonyl groups, acyl phosphine oxide groups, photo-acid generating groups, aromatic sulfonium or iodonium salt groups, cinnamate groups, chalcone groups, azo groups, aromatic conjugated light absorbing groups, ultraviolet absorber type groups, etc., but not limited to this. More specifically, the third functional group can include one or more of a combination of acrylate groups, methacrylic ester groups, epoxy groups, vinyl groups, alkoxy silane groups, etc., but not limited to this. Among them, the mechanism of introducing acrylate / methacrylic ester groups is that they can be co-photopolymerized with resin monomers under the action of a photoinitiator to construct a high-crosslinking, rigid-enhanced network structure, thereby improving the heat resistance, creep resistance and anti-crawling ability, and can directly participate in photoresist curing. The mechanism of introducing epoxy groups is that the epoxy groups can participate in ring-opening polymerization with amino groups, carboxyl groups in the resin system to strengthen the network and improve the thermal stability. The mechanism of introducing alkoxy silane (-SiOR) is that it can hydrolyze / condense during curing to form a siloxane covalent network with the resin, and also enhance the compatibility and integrity of the network structure.

[0034] In some embodiments, at least one end of the functionalized POSS structure monomer further has a fourth functional group, which can be a hydrophilic group or a hydrophobic group, wherein the hydrophilic group includes, but is not limited to, a combination of one or more of carboxyl, hydroxyl, amino, sulfonic acid, phosphonic acid, polyether chain segment; the hydrophobic group can be a combination of one or more of alkyl, aromatic group, fluorine-containing alkyl, siloxane chain segment, etc., to adjust resin compatibility and flexibility. At this time, the same functionalized POSS structure monomer simultaneously undertakes quantum dot fixation, resin crosslinking and compatibility regulation, forming a covalent / coordination ternary composite structure of POSS-quantum dot-resin, significantly enhancing the patterning accuracy, aging resistance and thermal stability.

[0035] Further, in order to enhance the crosslinking stability, the group introduced by the functionalized POSS structure monomer can be an imidazole group, a triazine group, a maleimide group, a silane coupling group, etc.

[0036] In some embodiments, the POSS structure monomer can include a combination of one or more of a closed cage silsesquioxane, a partially open cage silsesquioxane or a ladder silsesquioxane, etc., preferably a closed cage silsesquioxane.

[0037] In some preferred embodiments, the POSS structure monomer is a polyhedral or quasi-polyhedral structure with a Si-O-Si inorganic skeleton, the basic structural unit of which can be represented as (RSiO 1.5 ) n , wherein n is 6-20.

[0038] In some preferred embodiments, the POSS structure monomer can be a combination of one or more of a T8 type closed cage silsesquioxane, a T 10 type polyhedral silsesquioxane, a T 12 type polyhedral silsesquioxane, etc., and is particularly preferably a T8 type closed cage silsesquioxane, which has uniform end functional group distribution, high structural stability, is suitable for multifunctional modification and forms stable combination with quantum dots and resin systems.

[0039] In some more preferred embodiments, the POSS structure monomer is at least selected from one of the following structures: (1) a T8 type closed cage silsesquioxane; (2) a T 10 type polyhedral silsesquioxane or a T 12 type polyhedral silsesquioxane; (3) a partially open cage silsesquioxane, which has at least one un-closed Si-OH or Si-OR site on the cage body; (4) a ladder silsesquioxane, which has a double-chain ladder structure of Si-O-Si main chain.

[0040] The different structural POSS monomers described above are all realized by introducing carboxyl, mercapto, amino, phosphonic acid, acrylate, epoxy or a combination thereof at the end of the silicon atom, to realize chemical combination or coordination with the surface of quantum dots and the resin matrix.

[0041] In some preferred embodiments, each of the T8 type closed cage silsesquioxane contains 2-8 functional groups (coordination sites), which are a combination of the first functional group, the second functional group, the third functional group, and the fourth functional group, much larger than traditional small molecule ligands.

[0042] In some more preferred embodiments, the number ratio of the first functional group, the third functional group, and the fourth functional group is 1:1:0-4:2:2.

[0043] The functional group ratio of the functionalized POSS monomer of the present application can be accurately regulated according to the number of corners (8 or 12), the bonding density of quantum dots can be controlled, excessive ligand exchange leading to fluorescence quenching can be prevented, and the participation of the resin can also be controlled to achieve controllable network density after patterning.

[0044] In some more specific embodiments, the functionalized POSS monomer has a structure represented by formula (I): Formula (I) Wherein, R1 is the first functional group described above, R2 is the third functional group described above, R includes R1 or R2, etc., or other groups, such as other optional corners for solubility adjustment or steric hindrance regulation.

[0045] The present application designs at least one corner connected ligand group (mercapto, carboxyl, phosphate group, etc.) that can be bonded to the surface of quantum dots, so that quantum dots can be directly combined with functionalized POSS monomers through coordination or covalent bond to form a POSS-quantum dot (QDs) complex. When the POSS-quantum dot complex is added with a photoresist component, the quantum dots are no longer independent particles, but have been embedded in the backbone of the functionalized POSS monomer to form a quantum dot-POSS-photoresist overall network structure, which not only limits the domain, but also improves the thermal, optical and chemical stability and the ability to resist blue light and light bleaching performance. The shell on the surface of the quantum dot can also increase the mechanical rigidity and thermal stability layer, effectively reducing the ligand shedding during exposure / baking.

[0046] Moreover, the quantum dots of the present application are pre-fixed in the colloid, which can reduce QDs migration and agglomeration, improve the resolution of the pattern edge, and realize high-resolution patterning.

[0047] Specifically, the functionalized POSS monomer can be designed as a variety of groups to adapt to different monomer resin systems, thereby having high compatibility.

[0048] In some embodiments, the quantum dots can include a combination of one or more of Group IV quantum dots, Group II-VI quantum dots, Group IV-VI quantum dots, Group III-V quantum dots, etc., but not limited thereto.

[0049] In some more preferred embodiments, the quantum dots can include a combination of one or more of CdSe / ZnS, CdS / ZnS, CdZnSe / ZnS, CdZnSeS / ZnS, CdSe / CdS, InP / ZnS, AgInGaS / ZnS, etc., but not limited thereto.

[0050] In some embodiments, the content of quantum dots in the POSS-quantum dot complex is 5-50 wt%, preferably 5-40 wt%, and more preferably 5-30 wt%.

[0051] In some embodiments, when a photoresist base is included, the content of POSS-quantum dot complex in the POSS-linkage-based quantum dot photoresist composite material is 1-40 wt%, preferably 1-30 wt%, and more preferably 5-20 wt%, and the rest is the photoresist base. Further, various functionalized POSS structure monomers (long chain, short chain, flexible, rigid) can be present in the quantum dot photoresist composite material of the present application, and the density of the network structure can be adjusted by the ratio of the functionalized POSS structure monomers, so as to improve the quantum dot light emission retention rate, improve the array uniformity, and the pattern resolution is not affected by the quantum dot agglomeration.

[0052] As another aspect of the technical solution of the present application, the preparation method of the above-mentioned POSS-linkage-based quantum dot photoresist composite material includes: connecting the quantum dots and the POSS structure monomer through covalent bond or coordination bond to form a POSS-quantum dot complex; mixing the POSS-quantum dot complex, or mixing the POSS-quantum dot complex and a photoresist system to obtain a POSS-linkage-based quantum dot photoresist composite material.

[0053] In some preferred embodiments, the mass ratio of the quantum dots to the POSS structure monomer is 1:1-1:9, preferably 1:2-1:4.

[0054] The photoresist system includes resin monomers, photoinitiators, solvents, etc.

[0055] In some embodiments, the resin monomer can include a combination of one or more of MMA (methyl methacrylate), MA (methyl acrylate), HEMA (2-hydroxyethyl methacrylate), BA (n-butyl acrylate), IBOA (isobornyl methacrylate, which can improve heat resistance and etching resistance), TMPTA (trimethylolpropane triacrylate), PETA (pentaerythritol tetraacrylate), N-acryloylmorpholine (ACMO) and its derivatives (which can improve high hardness and high heat resistance), and the like, but is not limited thereto.

[0056] In some preferred embodiments, the photoinitiator can include a combination of one or more of TPO (2,4,6-tris(methylphenyl)phenyl phosphine ketone (phenyl phosphine ketone photoinitiator)), Irgacure 819 (bis(2,4,6-trimethylphenyl) phosphine oxyl phenyl ketone), BAPO type photoinitiator (bis(2,4,6-trimethylphenyl) phosphine oxyl benzophenone), cationic photoinitiator (such as triaryl iodonium salt), and the like, but is not limited thereto.

[0057] In some preferred embodiments, the solvent can include one or a combination of PGMEA (propylene glycol methyl ether acetate), GBL (γ-butyrolactone), and the like, but is not limited thereto.

[0058] As another aspect of the technical solution of the present application, another POSS-linked quantum dot photoresist composite material is involved, which includes: a composite host network framework formed by combining a POSS structure monomer with a resin monomer, and quantum dots uniformly embedded inside the composite host network framework to form a ternary hybrid network, wherein the POSS structure monomer and the quantum dots are connected by a covalent bond or a coordination bond, and a dense coating layer is formed on the surface of the quantum dots.

[0059] In the quantum dot photoresist composite material, the POSS structure monomer and the resin monomer combine to form a composite host network framework, and the quantum dots are embedded inside the composite host network framework instead of being simply dispersed, and are more resistant to migration, swelling and exposure damage.

[0060] In the quantum dot photoresist composite material, the quantum dots, the POSS structure monomer and the resin form a ternary hybrid network, in which the quantum dots are bonded to the POSS structure monomer, the POSS structure monomer is bonded to the resin, and the resin is crosslinked with the resin.

[0061] In some preferred embodiments, the types of functionalized POSS structure monomers, quantum dots and resin monomers are as previously described, and will not be repeated here.

[0062] The mechanism of the functionalized POSS structure monomer combined with the resin monomer includes a chemical combination mechanism, a physical / non-covalent interaction mechanism, and a network structure effect.

[0063] Further, the chemical combination mechanism includes: 1. Covalent crosslinking of carboxyl / amino with photopolymerization monomers (i.e., resin monomers) The functionalized POSS structure monomer introduces carboxyl (-COOH), amino (-NH2), and the like functional groups at the end, which can chemically react with active groups in the photopolymerization monomers (such as acrylate, epoxy, or acrylamide), for example: the carboxyl can form a covalent bond with the allyl group of the acrylate monomer through esterification; the amino group can undergo ring-opening reaction with the epoxy group to form a covalent connection; the functionalized POSS structure monomer skeleton is directly crosslinked with the photoresist monomer segment, forming a chemically stable network structure; 2. Coordination with quantum dot surface The lone pair of electrons in the carboxyl or amino group at the end of the functionalized POSS structure monomer can form a coordination bond with the metal ions (such as Cd 2+ , Zn 2+ , In 3+ ) on the surface of the quantum dot, forming a stable POSS-QD complex; when the functionalized POSS structure monomer and the resin monomer coexist, the functionalized POSS structure monomer not only serves as a chemical bridge to fix the quantum dot, but also enhances the mechanical stability of the overall network through covalent bonds with the resin monomer.

[0064] Further, the physical / non-covalent interaction mechanism includes: 1. Hydrogen bond network formation The carboxyl or amino group at the end of the functionalized POSS structure monomer can form a hydrogen bond with the hydroxyl, ether bond, or ester group in the resin monomer, which enhances the compatibility between the functionalized POSS structure monomer and the resin, allowing the functionalized POSS structure monomer to uniformly disperse in the photoresist, preventing agglomeration or precipitation; 2. Van der Waals force and steric hindrance The cage-like rigid skeleton of the functionalized POSS structure monomer provides steric hindrance at the molecular scale, avoiding aggregation, while allowing the resin segments to form a uniform network structure during the curing process. This three-dimensional spatial structure can increase the crosslinking density, improving the mechanical properties and thermal stability of the resin.

[0065] Further, the network structure effect includes: 1. Dual anchoring effect Chemical bonding: functionalized POSS structure monomer forms covalent network with resin monomer, enhancing the overall colloid strength; coordination / hydrogen bond fixation: functionalized POSS structure monomer fixes quantum dots, improving dispersibility and fluorescence stability; dual action makes quantum dots uniformly distributed in the crosslinked network, improving micro / sub-micro patterning accuracy; 2. Crosslinking density adjustability By controlling the ratio of carboxyl / amino on the end of functionalized POSS structure monomer to photopolymerization monomer, the crosslinking density and rigidity of the network structure can be adjusted, thereby optimizing the viscosity, patternability and high-temperature resistance of the photoresist; 3. Interface chemistry regulation The organic end group (i.e. the fourth functional group) of the functionalized POSS structure monomer skeleton can adjust the hydrophobicity / hydrophilicity, improve the compatibility of the functionalized POSS structure monomer with the resin, and prevent quantum dot migration or phase separation; at the same time, the carboxyl and amino groups can also form chemical anchor points with the resin crosslinked network, further improving the heat resistance, light resistance and chemical aging resistance of the photoresist composite material.

[0066] In some preferred embodiments, the content of quantum dots in the POSS connection-based quantum dot photoresist composite material is 0.1-50 wt%, and the content of functionalized POSS structure monomer is 1-30 wt%.

[0067] As another aspect of the technical solution of the present application, the preparation method of the above-mentioned POSS connection-based quantum dot photoresist composite material comprises: uniformly mixing POSS structure monomer, quantum dots, resin monomer, photoinitiator and solvent to prepare a POSS connection-based quantum dot photoresist composite material.

[0068] In some embodiments, the preparation method comprises: mixing functionalized POSS structure monomer, quantum dots, resin monomer, photoinitiator and solvent to form a mixed solution, and magnetically stirring for 30-180 min to prepare a POSS connection-based quantum dot photoresist composite material.

[0069] In the mixed solution, the content of functionalized POSS structure monomer is 1-20 wt%, the content of quantum dots is 0.1-50 wt%, preferably 0.5-10 wt%, the content of resin monomer is 50-90 wt%, preferably 50-85 wt%, the content of photoinitiator is 0.1-5 wt%, preferably 1-5 wt%, and the balance is solvent. The types of resin monomer, photoinitiator and solvent are as described above.

[0070] In some preferred embodiments, the mixed solution can further include an auxiliary agent, which can be one or a combination of diluent, surface agent, etc., and the mass of the auxiliary agent accounts for 0-5 wt% of the total mass.

[0071] As another aspect of the present application, it relates to another POSS-linked quantum dot photoresist composite material, which comprises: a composite host network framework formed by combining POSS structure monomers with resin monomers, and quantum dots, which are directly mixed in a dispersed form between the composite host network framework.

[0072] Further, the types of the functionalized POSS structure monomers and the quantum dots are as previously described, which will not be repeated here.

[0073] Correspondingly, the preparation method of the POSS-linked quantum dot photoresist composite material comprises: first, combining POSS structure monomers with resin monomers to form a composite host network framework, and then directly mixing quantum dots in a dispersed form between the composite host network framework.

[0074] In some embodiments, the POSS-linked quantum dot photoresist composite material is suitable for two-photon polymerization (TPP) or ultraviolet lithography (UV) processes, preferably can be precisely patterned by photolithography, and has the characteristics of friendly pattern processing.

[0075] Further, the POSS-linked quantum dot photoresist composite material of the present application can be used as a single-component quantum dot photoresist (QDPR) or a dispersed quantum dot photoresist (QDPR). The dispersed quantum dot photoresist can be added to a common resin system as a nano-concentrated paste.

[0076] As another aspect of the present application, it also relates to the application of the POSS-linked quantum dot photoresist composite material in Micro-LED full-color display.

[0077] Correspondingly, another aspect of the present application also relates to a quantum dot patterning method, which comprises the following steps: Applying (such as spin coating or drop coating) the POSS-linked quantum dot photoresist composite material to the surface of a Micro-LED chip; Performing patterned exposure by mask exposure, laser scanning or TPP; After development, obtaining a patterned quantum dot pattern of the corresponding color (red, green, blue).

[0078] Further, the application thickness of the POSS-linked quantum dot photoresist composite material on the surface of the Micro-LED chip is generally 1-10 µm.

[0079] The application coats the above POSS connection-based quantum dot photoresist composite material on a Micro-LED chip array, and can realize selective patterning of red and green wavelength QD-POSS materials; after development, a fluorescent pattern of a corresponding color is formed between Micro-LED pixels; a submicron-level high-resolution pattern meets the needs of Micro-LED monolithic full-color.

[0080] Further, by adjusting different ligand groups of the POSS-quantum dot composite, the application can realize independent patterning of RGB channels and adapt to Micro-LED pixel-level full-color integration.

[0081] The quantum dots in the quantum dot photoresist composite material of the application are more uniformly distributed (have high dispersity), patterned light emission is more stable, and color saturation and uniformity are better than those of the prior art. Moreover, the application can realize high-resolution full-color patterning of independent three-color channels on a Micro-LED monolithic substrate, and has higher functionality and applicability in actual application.

[0082] The specific embodiments of the application will be described in more detail below with reference to the embodiments, but the embodiments do not constitute a limitation on the application. All variations that are conceived or derived from the disclosure of the application are considered to be within the protection scope of the application.

[0083] The raw materials used in the embodiments of the application are all commercially available.

[0084] The instruments and equipment used in the following embodiments are all conventional equipment in the relevant field, and the performance tests are all in accordance with the requirements of conventional standards.

[0085] The method of thiol exchange used in the following embodiments can be using anhydrous organic solvents such as chloroform (CHCl3), toluene or dichloromethane (DCM); mixing the quantum dot solution with the functionalized POSS monomer at a ratio of 1:3~1:10 of the molar amount of the quantum dot surface ligand (POSS is excessive to ensure complete exchange); stirring magnetically at room temperature or with slight heating (25~50 ℃) to avoid degradation of the quantum dots for 2~12 hours, which can be appropriately adjusted according to the concentration of the quantum dots and the POSS. After the exchange is completed, free POSS and residual original ligands are removed by ethanol or acetone precipitation and centrifugation, and are redispersed in the target solvent (such as toluene or photoresist resin solvent).

[0086] Example 1 Preparation of a POSS connection-based CdSe / ZnS quantum dot photoresist composite material 1. Provide a functionalized POSS structure monomer (POSS-(-CH2=CHCOO-)6-(SH)2), the structure is shown in formula (II): Formula (II) wherein R1 is -SH and R2 is an acrylate group.

[0087] 2. Quantum dot modification CdSe / ZnS quantum dots with surface coated by tri-n-octylphosphine (TOP) / trioctylphosphine oxide (TOPO) were used to form POSS-QDs complex by replacing part of surface ligands with thiol sites in POSS-(-CH2=CHCOO-)6-(SH)2 through thiol exchange. The thiol exchange was carried out in organic solvent at room temperature to 50 ℃, and the exchange time was 2-12 h. The POSS structure monomer was added in excess to achieve partial or complete ligand replacement.

[0088] 3. Preparation of photoresist composite material POSS-QDs complex prepared in step 2 was dispersed in the following mixture: tri-functional monomer of acrylic acid (TMPTA) 50 wt%, photoinitiator (TPO) 2 wt%, PGMEA solvent 30 wt%, and POSS-QDs complex 18 wt%, wherein the content of QDs was 15 wt%. After magnetic stirring for 30 minutes and ultrasonic defoaming treatment for 1-20 min, a transparent and stable quantum dot photoresist composite material was obtained by filtration.

[0089] 4. Patterning process The quantum dot photoresist composite material prepared in step 3 was spin-coated on a Micro LED substrate, and then subjected to ultraviolet mask exposure, 60 s curing, and development to form a red pattern with a resolution of 10 μm.

[0090] The quantum dot photoresist composite material of the present embodiment has direct connection of quantum dots, uniform distribution, high stability, and good pattern conformality.

[0091] Example 2 Preparation of CdSe / CdS quantum dot photoresist composite material based on carboxyl functionalized POSS connection 1. Provide functionalized POSS structure monomer A carboxyl functionalized POSS structure monomer was provided, and its structure is represented as: POSS-(COOH)2-(CH2=CHCOO-)6, wherein the carboxyl group serves as a quantum dot coordination group, and the acrylate group serves as a photopolymerization active group.

[0092] 2. Quantum dot modification CdSe / CdS core-shell structure quantum dots coated with oleic acid / oleylamine ligand on the surface were used to form POSS-QDs complex by carboxyl coordination exchange, which makes part of the quantum dot surface ligand be replaced by the carboxyl group in the POSS monomer. The coordination exchange is carried out in organic solvent at room temperature to 60 ℃, and the reaction time is 4-12 h, and the POSS monomer is added in excess relative to the quantum dot surface ligand.

[0093] 3. Preparation of photoresist composite material The POSS-QDs complex obtained in step 2 is dispersed in the following mixed system: acrylic trifunctional monomer (TMPTA) 50 wt%, photoinitiator (TPO) 2 wt%, PGMEA solvent 30 wt%, and POSS-QDs complex 18 wt%, wherein the quantum dot content is 15 wt%.

[0094] After magnetic stirring for 30-60 min and ultrasonic debubbling for 1-20 min, filtration is performed to obtain transparent and stable quantum dot photoresist composite material.

[0095] 4. Patterning process The above quantum dot photoresist composite material is spin-coated on the surface of a Micro-LED substrate, and is cured by ultraviolet mask exposure for 60 s to form a red light-emitting pattern with a resolution of about 2 μm after development.

[0096] Example 3 Preparation of InP / ZnS quantum dot photoresist composite material based on amino-functionalized POSS connection 1. Provide functionalized POSS monomer A kind of amino-functionalized POSS monomer is provided, and its structure is represented as: POSS-(NH2)2-(CH2=CHCOO-)6, wherein the amino group is used as a quantum dot surface coordination and reaction group.

[0097] 2. Quantum dot modification InP / ZnS core-shell quantum dots coated with fatty amine ligand on the surface are used to form POSS-QDs complex by the coordination of amino group and quantum dot surface Zn 2+ , wherein the reaction is carried out in an inert atmosphere at 30-70 ℃, and the reaction time is 2-8 h.

[0098] 3. Preparation of photoresist composite material The obtained POSS-QDs complex is added to the following photoresist system: IBOA / ACMO mixed monomer 48 wt%, TMPTA 10 wt%, photoinitiator (TPO or Irgacure 819) 2 wt%, PGMEA 22 wt%, POSS-QDs complex 18 wt%, wherein the content of quantum dots is 10 wt%; After mixing uniformly, degassing and filtering, a quantum dot photoresist composite material suitable for a photoetching process is obtained.

[0099] 4. Patterning process The patterning process is performed by using ultraviolet exposure, and a green light-emitting micro-pattern with high uniformity can be obtained.

[0100] Example 4 Preparation of AgInGaS / ZnS quantum dot photoresist composite material based on phosphonic acid functionalized POSS connection 1. Provide functionalized POSS monomer A phosphonic acid functionalized POSS monomer is provided, and its structure is represented as: POSS-(PO3H2)2-(CH2=CHCOO-)6. The phosphonic acid group is used to form a strong coordination bond with the surface of the quantum dot shell.

[0101] 2. Quantum dot modification AgInGaS / ZnS quantum dots with a thiol or amine ligand coated surface are used. Through the multi-dentate coordination of the phosphonic acid group with the surface of the ZnS shell, the POSS monomer is fixed on the surface of the quantum dots to form a stable POSS-QDs complex. The reaction is carried out at 40-80 °C, and the reaction time is 4-10 h.

[0102] 3. Preparation of photoresist composite material The POSS-QDs complex is mixed with the following components: TMPTA 45 wt%, PETA 10 wt%, photoinitiator (BAPO) 2 wt%, GBL / PGMEA mixed solvent 25 wt%, and POSS-QDs complex 18 wt%, wherein the content of quantum dots is 30 wt%.

[0103] After thorough mixing and degassing, a quantum dot photoresist composite material is obtained.

[0104] 4. Patterning process Curing and developing are performed by using a mask exposure method, and a stable green light-emitting pattern can be formed.

[0105] Example 5 Quantum dot photoresist composite material based on phosphine oxide or selenol functionalized POSS connection The steps of the present embodiment are basically the same as those of Embodiments 2-4, except that the functionalized POSS structure monomer end position introduces phosphine oxide (P=O) or selenol group (–SeH), and the phosphine oxide is combined with the metal ions on the surface of the quantum dots through strong polar coordination; the selenol group forms M–Se bond with the metal on the surface of the quantum dots, which has higher thermal stability than M–S bond.

[0106] The obtained quantum dot photoresist composite material still maintains high luminous intensity and pattern integrity under high-temperature exposure and long-time aging conditions.

[0107] Embodiment 6 Preparation of CdSe / ZnS quantum dot photoresist composite material based on combination of quantum dots with unmodified POSS after ligand exchange 1. Quantum dot ligand exchange CdSe / ZnS core-shell quantum dots with a surface coated with tri-n-octylphosphine (TOP) / trioctylphosphine oxide (TOPO) are provided.

[0108] The CdSe / ZnS core-shell quantum dots are mixed with a low-molecular ligand containing a mercapto group (such as mercaptoacetic acid, mercaptoacrylic acid, or a dimercapto compound) in an organic solvent, and through mercapto exchange, part of the ligands on the surface of the quantum dots are replaced by mercapto ligands, to obtain quantum dots carrying mercapto active sites on the surface. The ligand exchange reaction is carried out at 25-60 ℃, and the reaction time is 2-10 h. The mercapto ligand is added in excess relative to the surface ligands of the quantum dots.

[0109] 2. Combination of quantum dots with POSS The surface-modified quantum dots obtained in step 1 are mixed with POSS molecules (such as octaisobutyl POSS or octaphenyl POSS) that have not been end-functionalized, and under stirring conditions, the mercapto groups on the surface of the quantum dots are combined with the Si–O skeleton or the surface organic groups of the POSS through coordination, hydrogen bonding, or van der Waals interaction, to obtain a POSS-QDs composite.

[0110] 3. Preparation of photoresist composite material The above POSS-QDs composite is added to the following photoresist system: 50 wt% of tri-functional acrylate monomer (TMPTA), 2 wt% of photoinitiator (TPO), 30 wt% of PGMEA solvent, and 18 wt% of POSS-QDs composite, wherein the content of quantum dots is 20 wt%. After magnetic stirring for 30 min and defoaming treatment, the transparent and stable quantum dot photoresist composite material is obtained by filtration.

[0111] 4. Pattern processing The quantum dot photoresist composite material is spin-coated on the surface of a substrate, is cured and developed by ultraviolet exposure to form a high-resolution luminescent pattern.

[0112] Example 7 Preparation of InP / ZnS quantum dot photoresist composite material based on carboxyl ligand modified quantum dots and unmodified POSS 1. Quantum dot ligand exchange An InP / ZnS core-shell quantum dot with a surface coated by a fatty amine ligand is provided, and a carboxyl ligand (such as acrylic acid, methacrylic acid or a polycarboxyl molecule) is used to exchange the ligand of the quantum dot, so that the quantum dot surface carries a carboxyl functional group.

[0113] 2. Quantum dots and POSS The quantum dots with carboxyl groups on the surface are mixed with unmodified POSS molecules, and the carboxyl groups and the silicon-oxygen skeleton or organic substituents of the POSS form a composite structure through multi-point weak coordination and intermolecular interaction to obtain a POSS-QDs composite.

[0114] 3. Preparation of photoresist composite material The POSS-QDs composite is dispersed in the following system: IBOA / ACMO mixed monomers 45 wt%, TMPTA 10 wt%, photoinitiator (Irgacure 819) 2 wt%, PGMEA 25 wt%, and POSS-QDs composite 18 wt%, wherein the content of quantum dots is 25 wt%. After sufficient mixing, a quantum dot photoresist composite material is obtained.

[0115] 4. Patterning process A uniform and stable green luminescent pattern is obtained by using ultraviolet mask exposure for patterning.

[0116] Example 8 Preparation of AgInGaS / ZnS quantum dot photoresist composite material based on phosphonic acid ligand modified quantum dots and unmodified POSS 1. Quantum dot ligand exchange An AgInGaS / ZnS core-shell quantum dot is provided, and a ligand containing a phosphonic acid group (such as an alkyl phosphonic acid or a polyphosphonic acid ligand) is used to exchange the surface ligand of the quantum dot, so that the quantum dot surface carries a phosphonic acid group.

[0117] 2. Quantum dots and POSS The phosphonic acid modified quantum dots are mixed with unfunctionalized POSS molecules, and the phosphonic acid group forms a strong coordination with the metal ions of the quantum dot shell, and at the same time, the POSS is coated around the quantum dots through multi-point adsorption to form a POSS-QDs composite.

[0118] 3. Preparation of photoresist composite material The POSS-QDs composite is mixed with the following components: TMPTA 45 wt%, PETA 10 wt%, photoinitiator (BAPO) 2 wt%, GBL / PGMEA mixed solvent 25 wt%, and POSS-QDs composite 18 wt%, wherein the content of quantum dots is 40 wt%. After sufficient mixing, a quantum dot photoresist composite material is prepared.

[0119] 4. Patterning process Through the exposure and development process, a high-stability red-orange light-emitting micro-pattern can be obtained.

[0120] Example 9 On the basis of Examples 6-8, the quantum dot ligand is replaced by one or more of amino, phosphine oxide, and selenol groups.

[0121] The POSS structure monomer is a cage-like siloxane molecule without introducing a photopolymerization active group.

[0122] The quantum dots form a composite structure through multi-point interaction between the surface functional ligand and the POSS, and then are mixed with a photoresist resin system to prepare a quantum dot photoresist composite material.

[0123] Example 10 Preparation of CdSe / ZnS quantum dot photoresist composite material based on functionalized POSS introducing methacrylate photopolymerization active groups 1. Provision of functionalized POSS structure monomer A functionalized POSS structure monomer introducing methacrylate photopolymerization active groups is provided, and its structure is represented as: POSS-( -O-CO-C(CH3)=CH2)6-(SH)2, wherein the POSS is a cage-like silsesquioxane structure, part of the terminal groups introduces a methacrylate group as a photopolymerization active site, and part of the terminal groups introduces a mercapto group as a quantum dot binding site.

[0124] 2. Quantum dot modification and binding CdSe / ZnS core-shell quantum dots with a surface coated by tri-n-octylphosphine (TOP) / trioctylphosphine oxide (TOPO) are provided.

[0125] The quantum dots are mixed with the functionalized POSS monomer in step 1 in anhydrous organic solvent, and through the coordination of mercapto groups with quantum dot surface metal ions, partial replacement of the quantum dot surface ligand is achieved, forming a POSS-QDs composite.

[0126] 3. Preparation of photoresist composite material The above-mentioned POSS-QDs complex was added to the following system: 45 wt% trimethylolpropane methacrylate (TMPTMA), 20 wt% functionalized POSS-QDs complex (including 45 wt% quantum dots), 2 wt% photoinitiator (TPO), and 33 wt% PGMEA solvent; After magnetic stirring for 30 minutes, degassing, and filtration, a uniform and transparent quantum dot photoresist composite material was obtained.

[0127] 4. Graphical processing Quantum dot photoresist is spin-coated onto the substrate surface, cured and developed after 60 seconds of UV exposure, which can form a red luminescent pattern with a resolution better than 2 μm.

[0128] Example 11 Preparation of InP / ZnS quantum dot photoresist composite material based on methacrylate-functionalized POSS 1. Provision of Functional POS Systems A class of POSS monomers with methacrylate groups at the terminal positions are provided, wherein the number of methacrylate groups introduced in the structure is 2 to 8, for participation in photoinitiated free radical polymerization reactions.

[0129] 2. Quantum dot bonding InP / ZnS quantum dots with surface modified by carboxyl or amino ligands are mixed with the functionalized POSS to form a stable POSS-QDs complex through coordination and intermolecular forces.

[0130] 3. Construction of photoresist system The POSS-QDs complex was added to the following mixture: IBOA 30 wt%, ACMO 15 wt%, TMPTMA 10 wt%, photoinitiator (Irgacure 819) 2 wt%, solvent (PGMEA): 43 wt%; wherein, the quantum dot content in the POSS-QDs complex was 26 wt%.

[0131] 4. Graphical applications After ultraviolet exposure and development, a uniform and stable green luminescent pattern is obtained.

[0132] Example 12 In the above embodiments 10 and 11, the photopolymerization active group is a methacrylate group, which can directly participate in the UV-initiated free radical polymerization reaction, so that the functionalized POSS is embedded in the photoresist resin network as a crosslinking node; the quantum dots are fixed in the crosslinking network through the multi-point anchoring effect of POSS, thereby significantly improving the dispersion stability, heat resistance and pattern conformation ability of quantum dots in photoresist.

[0133] Example 13 Preparation of functionalized POSS connected CdSe / CdS quantum dots photoresist composite based on introducing epoxy photopolymerization active group 1. Providing functionalized POSS monomer Provided is a functionalized POSS monomer with terminal introduction of epoxy groups, the structure of which is represented as: POSS-( -CH2-CHO-CH2)6-(SH)2, wherein POSS is a cage-like silsesquioxane structure, part of which is introduced with epoxy groups as a photopolymerization active site, and part of which is introduced with mercapto groups for coordination and binding of quantum dots.

[0134] 2. Quantum dot binding Provided are CdSe / CdS quantum dots with a TOP / TOPO coated surface.

[0135] The quantum dots are mixed with the functionalized POSS monomer in step 1 in anhydrous solvent, and through coordination of mercapto groups with metal ions on the surface of the quantum dots, part of the surface ligands are replaced, forming a stable POSS-QDs composite.

[0136] 3. Preparation of photoresist composite The above POSS-QDs composite is added to the following system: 40 wt% of epoxy resin monomer (such as bisphenol A type epoxy resin), 15 wt% of active diluent (such as 1,4-butanediol diglycidyl ether), 20 wt% of POSS-QDs composite, wherein the content of quantum dots is 20 wt%, 2 wt% of cationic photoinitiator (such as triaryl iodonium salt), and 23 wt% of PGMEA solvent.

[0137] After stirring and defoaming treatment, a uniform and stable quantum dot photoresist composite is obtained.

[0138] 4. Pattern processing The photoresist is spin-coated on the surface of the substrate, and after UV exposure for 60 s, cationic ring-opening polymerization of the epoxy groups occurs, and after development, a red luminescent pattern is obtained.

[0139] Example 14 Preparation of functionalized POSS connected AgInGaS / ZnS quantum dots photoresist composite based on introducing vinyl photopolymerization active group 1. Providing functionalized POSS monomer Provided is a functionalized POSS monomer with terminal introduction of vinyl groups, the structure of which is represented as: POSS-( -CH=CH2)6-(COOH)2, wherein the vinyl group is used to participate in free radical polymerization, and the carboxyl group is used to form a coordination bond with metal ions on the surface of the quantum dots.

[0140] 2、Quantum dot modification and combination A AgInGaS / ZnS quantum dot with a carboxyl ligand pre-modified surface is provided, which is mixed with the functionalized POSS monomer to form a POSS-QDs complex through multi-point coordination.

[0141] 3、Photoresist system construction The POSS-QDs complex is added to the following mixed system: acrylate monomer (IBOA) 35 wt%, vinyl monomer (styrene or vinyl ether) 15 wt%, POSS-QDs complex 18 wt%, wherein the quantum dot content is 5.6 wt%; photoinitiator (BAPO) 2 wt%, solvent (GBL) 30 wt%;

[0142] After sufficient mixing, a quantum dot photoresist composite material is prepared.

[0143] 4、Patterning process A stable luminescent pattern is formed by developing after inducing radical polymerization of the vinyl group using ultraviolet exposure.

[0144] Example 15 Preparation of a POSS-quantum dot photoresist composite material with high quantum dot anchoring density 1、Functionalized POSS monomer A functionalized POSS monomer is provided, which is represented by the structure: POSS-(SH)4-(MA)2-(R)2, wherein -SH is a quantum dot bonding group; MA is a methacrylate group; -R is an inert short-chain alkyl group (such as methyl or ethyl), wherein the number ratio of -SH, MA and inert short-chain alkyl group is 4:2:2.

[0145] 2、Quantum dot combination CdSe / ZnS quantum dots with TOP / TOPO ligands on the surface are mixed with the functionalized POSS monomer described above to achieve high-density surface anchoring through multi-site thiol coordination, forming a POSS-QDs complex.

[0146] 3、Photoresist preparation and patterning The photoresist is prepared according to the same acrylate system as in Example 1 and exposed and developed.

[0147] Test results show that the quantum dot photoresist composite material of this embodiment has quantum dots that are strongly anchored, making it suitable for high-brightness, long-life applications.

[0148] Example 16 POSS-quantum dot photoresist composite material considering quantum dot stability and patterning accuracy 1. Functionalized POSS structure monomer A functionalized POSS structure monomer is provided, the structure of which is represented as: POSS-(COOH)2-(MA)4-(C8H 17 )2, wherein the number ratio of -COOH, MA and -C8H 17 is 2:4:2.

[0149] 2. Quantum dot combination InP / ZnS quantum dots are combined with the functionalized POSS structure monomer described above through carboxyl coordination to form a stable POSS-QDs complex.

[0150] 3. Photoresist preparation The POSS-QDs complex described above is added to the following system: TMPTA 50 wt%, IBOA 20 wt%, POSS-QDs complex 10 wt%, BAPO type photoinitiator 2 wt%, PGMEA solvent 18 wt%;

[0151] After stirring and defoaming treatment, a uniform and stable quantum dot photoresist composite material is obtained.

[0152] After UV exposure and development treatment, it can be concluded that this embodiment achieves a good balance between dispersibility, crosslinking density and pattern boundary definition, and is suitable for Micro-LED fine patterning.

[0153] Example 17 Highly crosslinked and highly moisture and heat resistant POSS-quantum dot photoresist composite material 1. Functionalized POSS structure monomer A functionalized POSS structure monomer is provided, the structure of which is represented as: POSS-(PO3H2)1-(Epoxy)5-(C 12 H 25 )2, wherein the number ratio of -PO3H2, Epoxy and -C 12 H 25 is 1:5:2.

[0154] 2. Quantum dot combination AgInGaS / ZnS quantum dots are used, which are connected to the functionalized POSS structure monomer described above through monodentate coordination of phosphonic acid groups to form a stable POSS-QDs complex.

[0155] 3. Photoresist preparation and curing The photoresist is prepared and exposed and developed according to the same epoxy cationic photoinitiating system as in Example 12. It can be concluded that the functionalized POSS structure monomer in this embodiment participates deeply in network crosslinking, and quantum dot migration is inhibited by the network structure, and the material exhibits excellent moisture and heat resistance and aging resistance.

[0156] Example 18 POSS-quantum dots photoresist composite based on methacrylate resin monomer 1. Resin monomer includes: methyl methacrylate (MMA), isobornyl methacrylate (IBOMA); 2. Composite system includes: MMA / IBOMA 45 wt%, the same functionalized POSS-QDs complex as in Example 2 20 wt%, photoinitiator (TPO) 2 wt%, PGMEA 33 wt%; After stirring and defoaming treatment, a uniform and stable quantum dot photoresist composite material is obtained.

[0157] 3. After ultraviolet exposure and development treatment, it can be concluded that the exposure shrinkage of this system is small, the pattern edge is stable, and it is suitable for high-resolution Micro-LED patterning.

[0158] Example 19 POSS-quantum dots photoresist composite based on multi-functional acrylate crosslinking resin 1. Resin monomer includes: trimethylolpropane triacrylate (TMPTA), pentaerythritol tetraacrylate (PETA); 2. Composite system includes: TMPTA / PETA 50 wt%, the same functionalized POSS-QDs complex as in Example 2 18 wt%, photoinitiator (BAPO) 2 wt%, solvent (GBL) 30 wt%; After stirring and defoaming treatment, a uniform and stable quantum dot photoresist composite material is obtained.

[0159] 3. After ultraviolet exposure and development treatment, it can be concluded that the crosslinking density of this system is high, the POSS structure monomer participates in network construction, and the heat resistance and aging resistance performance are significantly improved.

[0160] Example 20 POSS-quantum dots photoresist composite based on epoxy resin monomer 1. Resin monomer includes: bisphenol A type epoxy resin, 1,4-butanediol diglycidyl ether (active diluent); 2. Composite system includes: epoxy resin system 40 wt%, the same functionalized POSS-QDs complex as in Example 12 20 wt%, cationic photoinitiator (iodonium salt) 2 wt%, PGMEA 38 wt%;

[0161] After stirring and defoaming treatment, a uniform and stable quantum dot photoresist composite material is obtained.

[0162] 3. After UV exposure and development, it can be concluded that the system is not affected by oxygen inhibition during exposure, and is suitable for thick film and high depth of pattern.

[0163] Example 21 POSS-quantum dot photoresist composite based on vinyl / styrene resin monomer 1. Resin monomer, including: styrene, vinyl ether monomer; 2. Composite system including: vinyl resin system 35 wt%, the same as in example 13 POSS-QDs composite 22 wt%, photoinitiator (BAPO) 2 wt%, solvent (GBL) 41 wt%;

[0164] After stirring and defoaming treatment, a uniform and stable quantum dot photoresist composite material is obtained.

[0165] 3. After UV exposure and development, it can be concluded that the hydrophobic network and the POSS cage structure cooperate to significantly inhibit the fluorescence decay caused by water vapor intrusion.

[0166] Example 22 POSS-quantum dot photoresist composite based on hydroxyl-containing functional monomer 1. Resin monomer, including: 2-hydroxyethyl methacrylate (HEMA), ACMO or its derivatives; 2. Composite system including: HEMA / ACMO 40 wt%, the same as in example 7 POSS-QDs composite 20 wt%, photoinitiator (Irgacure 819) 2 wt%, PGMEA 38 wt%;

[0167] After stirring and defoaming treatment, a uniform and stable quantum dot photoresist composite material is obtained.

[0168] 3. After UV exposure and development, it can be concluded that the hydroxyl group forms a hydrogen bond with the surface of POSS / QDs, improving dispersion stability and pattern uniformity.

[0169] Example 23 POSS-quantum dot photoresist composite based on photopolymerization functionalized POSS 1. Functionalized POSS monomer structure A functionalized POSS monomer containing a photopolymerization active group is provided, and its structure is represented as: POSS-(methacrylate)6-(mercapto)2, wherein the mercapto group is used for coordination with the surface of quantum dots, and the methacrylate group is used for photopolymerization crosslinking; 2. Quantum dot modification The surface of TOP / TOPO coated CdSe / ZnS quantum dots is mixed with the functionalized POSS monomer above under inert atmosphere, and ligand exchange is performed by thiol-metal coordination to form a POSS-QDs composite.

[0170] 3. Preparation of resin-free photoresist The POSS-QDs composite above is directly added to the following system: POSS-QDs composite 98 wt%, photoinitiator (TPO) 2 wt%; After mixing evenly, a quantum dot photoresist composite material without resin monomers is obtained.

[0171] 4. Patterning process The obtained material is spin-coated on the surface of a Micro-LED substrate, after ultraviolet exposure, the POSS end methacrylate group is crosslinked and cured, and after development, a stable red quantum dot pattern is formed.

[0172] Example 24 Epoxy-functionalized POSS-quantum dot photoresist composite material 1. Functionalized POSS monomer An epoxy-functionalized POSS monomer is provided, and its structure is represented as: POSS-(epoxy)6-(phosphonic acid)2.

[0173] 2. Quantum dot modification InP / ZnS quantum dots pre-modified with phosphonic acid ligands on the surface are mixed with the functionalized POSS monomer, and a POSS-QDs composite is formed by phosphonic acid-metal coordination.

[0174] 3. Preparation of resin-free composite material The obtained POSS-QDs composite is added to the following system: POSS-QDs composite 97 wt%, cationic photoinitiator (iodonium salt) 3 wt%;

[0175] After mixing evenly, a quantum dot photoresist composite material without resin monomers is obtained.

[0176] 4. Patterning process Under ultraviolet exposure, the POSS end epoxy group undergoes ring-opening polymerization to form a three-dimensional crosslinked network by itself, achieving pattern curing.

[0177] Example 25 Sol-gel type POSS-quantum dot photoresist composite material 1. Functionalized POSS monomer A POSS monomer containing hydrolyzable silane groups is provided, and its structure is represented as: POSS-(Si-OR)6-(thiol)2. 2. Quantum dot modification CdSe / CdS quantum dots are exchanged with the functionalized POSS monomer through mercapto groups to form a POSS-QDs complex.

[0178] 3. Preparation of resin-free film-forming system The POSS-QDs complex is dissolved in an alcohol solvent, trace amounts of water and an acidic catalyst are added to initiate the hydrolysis and condensation of Si-OR to form a silicon-oxygen network.

[0179] 4. Patterning process The gelation area is controlled by mask exposure or local heating to achieve patterned film formation.

[0180] Example 26 Quantum dot photoresist composite material based on POSS-resin network and physical embedding of quantum dots 1. Construction of POSS-resin composite main network A functionalized POSS monomer, POSS-(methacrylate) 8, is mixed with an acrylic resin monomer (TMPTA) at a mass ratio of 1:4, and a photoinitiator (TPO) is added to form a three-dimensionally cross-linked POSS-resin composite main network framework under ultraviolet exposure. The POSS monomer participates in free radical polymerization through the terminal methacrylate group and is embedded in the resin network as a multifunctional cross-linking node to improve the rigidity and thermal stability of the network.

[0181] 2. Physical embedding of quantum dots CdSe / ZnS quantum dots with a TOP / TOPO coating on the surface are directly added to the above-mentioned POSS-resin prepolymer solution, and magnetic stirring is performed for 30 min to uniformly disperse the quantum dots in the system.

[0182] The quantum dots are not covalently or coordinately bonded to the POSS monomer or the resin monomer, but only exist in the form of physical dispersion in the mixed system before the formation of the POSS-resin cross-linked network.

[0183] 3. Preparation of photoresist composite material The above-mentioned mixed system is spin-coated on the surface of a substrate, and after ultraviolet exposure, the POSS and the resin monomer are cross-linked and cured to form a continuous three-dimensional network structure; the quantum dots are confined in the grid pores of the network structure to obtain a quantum dot photoresist composite material based on a POSS-resin network.

[0184] 4. Patterning process The obtained quantum dot photoresist composite material is applied to the surface of a Micro-LED chip, and through ultraviolet mask exposure and development processes, a patterned quantum dot light-emitting region is obtained.

[0185] Example 27 Quantum dot confined photoresist composite based on high crosslinking density POSS-resin network 1. Composite host network construction Mix functionalized POSS structure monomer POSS-(methacrylate)6-(hydrophobic alkyl)2 with multifunctional acrylate monomer TMPTA, PETA in proportion to form a high crosslinking density prepolymer system.

[0186] 2. Quantum dot addition method Directly disperse AgInS2 / ZnS quantum dots in the above prepolymer system, the quantum dots do not carry a reactive ligand and do not chemically bond with POSS or resin, but only exist in a physical dispersion state.

[0187] 3. Curing and confinement After ultraviolet exposure, the POSS and resin monomers rapidly crosslink to form a dense network, and the quantum dots are confined in the nanoscale pores of the crosslinked network.

[0188] Example 28 Preparation of quantum dot photoresist composite based on POSS-resin-quantum dot ternary hybrid network 1. Pre-mixing of functionalized POSS structure monomer and resin monomer Provide a functionalized POSS structure monomer, which is a T8 type closed cage silsesquioxane, which introduces two types of functional groups on the outside of the cage: one type is a thiol functional group that can coordinate or covalently connect with the surface of the quantum dot; the other type is an acrylate functional group that can participate in photopolymerization;

[0189] Mix the functionalized POSS structure monomer with resin monomer, wherein the resin monomer is trimethylolpropane triacrylate (TMPTA), the mass ratio of functionalized POSS structure monomer to resin monomer is 10:90, add a photoinitiator diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO) in an amount of 2 wt% of the total mass of the system, and add propylene glycol methyl ether acetate (PGMEA) as a solvent, which accounts for 30 wt% of the total mass of the system, and magnetically stir to form a uniform transparent precursor mixture.

[0190] 2. Introduction of quantum dots and construction of ternary hybrid network Provide CdSe / ZnS core-shell structure quantum dots coated with tri-n-octylphosphine (TOP) / trioctylphosphine oxide (TOPO) on the surface, and add them to the precursor mixture obtained in step 1.

[0191] Under stirring, the metal ions on the surface of the quantum dots are coordinated to the thiol functional groups on the functionalized POSS monomer, and at the same time, the acrylate functional groups on the functionalized POSS monomer participate in the subsequent photopolymerization reaction together with the resin monomer.

[0192] In the above manner, the quantum dots are anchored in the three-dimensional network framework constructed by the POSS monomer and the resin monomer during the reaction, and the quantum dots are uniformly embedded in the composite host network framework to form a POSS-resin-quantum dot ternary hybrid network structure, in which the quantum dots act as nodes or crosslinking points in the network.

[0193] 3. Preparation of quantum dot photoresist composite material The above mixed system is continuously magnetically stirred for 30 min to allow the quantum dots, the functionalized POSS monomer and the resin monomer to fully react and uniformly distribute, and then is subjected to ultrasonic defoaming treatment for 5 min and filtered through a 0.45 μm filter membrane to obtain a stable transparent quantum dot photoresist composite material based on a ternary hybrid network structure. The content of the quantum dots in the composite material is 35 wt%.

[0194] 4. Patterning The quantum dot photoresist composite material prepared in step 3 is spin-coated on the surface of a Micro-LED chip, pre-baked, and subjected to patterned curing by ultraviolet mask exposure, with an exposure time of 60 s. After development, a patterned red quantum dot light-emitting pattern is obtained, with a minimum resolution of 10 μm.

[0195] In this embodiment, the quantum dots are coordinated to the functionalized POSS monomer and further participate in the photopolymerization network construction of POSS-resin, so that the quantum dots are uniformly embedded in the composite host network framework to form a stable ternary hybrid network structure. This structure can effectively limit the migration and aggregation of the quantum dots in the photoresist system, improve the stability of the quantum dots in light, heat and humid heat environments, and at the same time ensure good pattern resolution and pattern shape retention.

[0196] Test Example Full-color patterning Red light (CdSe) and green light (InP) POSS-QDs photoresist composite materials are prepared according to the method of Example 1.

[0197] Three color regions are patterned on a Micro LED chip using three mask alignment exposure steps to realize a single-chip full-color display function.

[0198] Each pattern has a size of 3 μm × 3 μm and a spacing of 2 μm, and no color crosstalk is observed, and the heat resistance is better than that of conventional QD doped photoresist.

[0199] Comparative Example 1 Comparative Example 1 is similar to Example 1, using the same photoresist system and quantum dots, but differs in that the POSS structure monomer does not contain a ligand group (only end group acrylate).

[0200] The quantum dot photoresist composite material prepared in Comparative Example 1 was spin-coated on a Micro LED substrate, subjected to ultraviolet mask exposure, cured for 60 s, developed, and the quantum dot distribution and pattern formation were observed.

[0201] The observation results are as follows: 1) The quantum dots do not form covalent / coordination connections with the POSS structure monomer, and can only rely on network confinement or dispersants for maintenance; 2) The quantum dots are freely dispersed, and self-absorption is severe after curing, reducing resolution; 3) The thermal, light, and humidity stabilities are lower than Example 1.

[0202] The test data corresponding to the blue light aging and humidity aging of the materials of Examples 1-28 and Comparative Example 1 are shown in Table 1: Table 1 Test data of the materials of Examples 1-28 and Comparative Example 1 Examples Material Type Blue light aging retention / 1000h (%) Hygrothermal aging retention 85°C / 85%RH 1000h (%) Example 1 POSS-CdSe / ZnS thiol bonding 91 90 Example 2 POSS-CdSe / ZnS carboxyl bonding 90 90 Example 3 POSS-InP / ZnS amino bonding 92 91 Example 4 POSS-AgInGaS / ZnS phosphonic acid bonding 93 92 Example 5 POSS-CdSe / ZnS phosphine oxide bonding 90 89 Example 6 POSS-CdSe / ZnS thiol bonding 95 94 Example 7 POSS-InP / ZnS carboxyl bonding 88 87 Example 8 POSS-AgInGaS / ZnS phosphonic acid bonding 89 88 Example 9 POSS-InP / ZnS phosphine oxide bonding 90 89 Example 10 Functionalized POSS-CdSe / ZnS-thiol bonding with methacrylate photopolymerizable active groups 88 87 Example 11 Functionalized POSS-InP / ZnS with methacrylate groups 90 89 Example 12 POSS-CdSe / ZnS carboxyl bonding with methacrylate photopolymerizable active groups 70 70 Example 13 POSS-CdSe / CdS thiol bonding with epoxy photopolymerizable active groups 71 70 Example 14 POSS-AgInGaS / ZnS carboxyl bonding with vinyl photopolymerizable active groups 70 70 Example 15 POSS-CdSe / ZnS thiol bonding 69 70 Example 16 POSS-InP / ZnS carboxyl bonding 70 70 Example 17 POSS-AgInGaS / ZnS phosphonic acid bonding 92 91 Example 18 Based on methacrylate resin monomers 90 89 Example 19 Based on multifunctional acrylate crosslinking resins 91 90 Example 20 Based on epoxy resin monomers 90 89 Example 21 Based on vinyl / styrene resin monomers 93 92 Example 22 Based on hydroxyl containing functional monomers 91 90 Example 23 No resin monomer added - POSS-CdSe / ZnS thiol bonding 68 67 Example 24 No resin monomer added - POSS-CdSe / ZnS phosphonic acid bonding 71 70 Example 25 No resin monomer added - POSS-CdSe / ZnS thiol bonding 72 71 Example 26 QDs physically dispersed in POSS-resin network 65 64 Example 27 High crosslinking density POSS-resin network + QDs physically dispersed 66 65 Example 28 POSS-resin-quantum dot ternary hybrid network structure 92 95 Comparative Example 1 QDs physically dispersed only, no POSS modification 45 42

[0203] Figure 1 is the photoetching result of the photoresist material in Comparative Example 1; Figure 2 is the photoetching result of the POSS connection-based quantum dot photoresist composite material prepared in Example 1; Figure 3 is the photoetching result of the POSS connection-based quantum dot photoresist composite material prepared in Example 10; Figure 4 is the photoetching result of the POSS connection-based quantum dot photoresist composite material prepared in Example 21; Figure 5 Examples Material Type Blue light aging retention / 1000h (%) Hygrothermal aging retention 85°C / 85%RH 1000h (%) Example 1 POSS-CdSe / ZnS thiol bonding Example 2 POSS-CdSe / ZnS carboxyl bonding Example 3 POSS-InP / ZnS amino bonding Example 4 POSS-AgInGaS / ZnS phosphonic acid bonding Example 5 POSS-CdSe / ZnS phosphine oxide bonding Example 6 POSS-CdSe / ZnS thiol bonding Example 7 POSS-InP / ZnS carboxyl bonding Example 8 POSS-AgInGaS / ZnS phosphonic acid bonding Example 9 POSS-InP / ZnS phosphine oxide bonding Example 10 Functionalized POSS-CdSe / ZnS-thiol bonding with methacrylate photopolymerizable active groups Example 11 Functionalized POSS-InP / ZnS with methacrylate groups Example 12 POSS-CdSe / ZnS carboxyl bonding with methacrylate photopolymerizable active groups Example 13 POSS-CdSe / CdS thiol bonding with epoxy photopolymerizable active groups Example 14 POSS-AgInGaS / ZnS carboxyl bonding with vinyl photopolymerizable active groups Example 15 POSS-CdSe / ZnS thiol bonding Example 16 POSS-InP / ZnS carboxyl bonding Example 17 POSS-AgInGaS / ZnS phosphonic acid bonding Example 18 Based on methacrylate resin monomers Example 19 Based on multifunctional acrylate crosslinking resins Example 20 Based on epoxy resin monomers Example 21 Based on vinyl / styrene resin monomers Example 22 Based on hydroxyl containing functional monomers Example 23 No resin monomer added - POSS-CdSe / ZnS thiol bonding Example 24 No resin monomer added - POSS-CdSe / ZnS phosphonic acid bonding Example 25 No resin monomer added - POSS-CdSe / ZnS thiol bonding Example 26 QDs physically dispersed in POSS-resin network Example 27 High crosslinking density POSS-resin network + QDs physically dispersed Example 28 POSS-resin-quantum dot ternary hybrid network structure Comparative Example 1 QDs physically dispersed only, no POSS modification Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Examples Material Type Blue light aging retention / 1000h (%) Hygrothermal aging retention 85°C / 85%RH 1000h (%) is the photoetching result of the QDs dissolution scheme in Example 26.

[0204] Comparing the results of the above examples and Comparative Example 1, it can be concluded that the quantum dots in the POSS connection-based quantum dot photoresist composite material of the present application are uniformly dispersed in the photoresist, can maintain the original distribution after curing, the pattern edges are clear, the cross-contamination between pixels is significantly reduced, and high-resolution micron-level or even sub-micron-level three-color pixel patterning is achieved. The quantum dots are stably distributed in the cured network and exhibit excellent durability and resistance to blue light bleaching in thermal, light, and humidity environments. In contrast, the quantum dots in Comparative Example 1 rely only on physical dispersion or network confinement, and after curing, agglomeration, migration, or edge blurring phenomena easily occur, the three-color patterning effect is unstable, and the thermal and light stabilities are significantly lower than those of the above examples.

[0205] Therefore, the POSS connecting-based quantum dot photoresist composite material of the present application achieves unexpected technical effects in quantum dot uniformity, pattern shape retention, stability and pixel-level full-color integration.

[0206] In addition, the present inventors have also carried out tests with other raw materials, process operations and process conditions described in the present specification with reference to the foregoing examples, and all obtained relatively ideal results.

[0207] The technical features of the foregoing examples can be combined in any manner, and in order to make the description brief, all possible combinations of the technical features in the foregoing examples have not been described, however, as long as the combinations of the technical features do not exist in contradiction, they shall be considered as falling within the scope of the present specification.

[0208] Although the present application has been described with reference to the illustrative embodiments, it will be understood by those skilled in the art that various other changes in form and details can be made therein without departing from the spirit and scope of the application. In addition, many modifications can be made to adapt a particular situation or material to the teachings of the application without departing from the scope thereof. Therefore, it is intended that the present application not be limited to the disclosed embodiments, but will include all embodiments falling within the scope of the appended claims.

Claims

1. A POSS-linked quantum dot photoresist composite material, characterized in that, The POSS-quantum dot complex includes a plurality of POSS-quantum dot complexes; the POSS-quantum dot complex includes a bridged structure formed by covalent bonding or coordination bonding between a POSS structural monomer and a quantum dot, the quantum dots are uniformly embedded in the skeleton of the POSS structural monomer and form a three-dimensional network structure, and a dense coating layer is formed on the surface of the quantum dots.

2. The POSS-linked quantum dot photoresist composite of claim 1, wherein: The POSS-quantum dot complex is formed by coordination bonding or group substitution between the functionalized POSS structural monomer and the surface metal ions of the quantum dot, at least one end of the functionalized POSS structural monomer has a first functional group as a ligand group for connecting with the surface of the quantum dot, and the first functional group includes one or more combinations of mercapto, carboxyl, amino, phosphonic acid, phosphine oxide, selenol, acrylate, and epoxy groups.

3. The POSS-linkage based quantum dot photoresist composite of claim 2, wherein: The POSS-quantum dot complex is formed by coordination bonding or group substitution between the functionalized POSS structural monomer and the quantum dot with a first pre-modified ligand, and the first pre-modified ligand contains one or more combinations of phosphonic acid, mercapto, selenol, carboxyl, acrylate, and epoxy groups.

4. The POSS-linkage based quantum dot photoresist composite of claim 3, wherein: The surface of the quantum dot also has a second pre-modified ligand as an active end group, the second pre-modified ligand includes one or more combinations of acrylic acid ligand, methacrylic acid ligand, epoxy ligand, isocyanate ligand, mercapto ligand, and amino ligand; at least one end of the functionalized POSS structural monomer also has a second functional group matching the second pre-modified ligand, and the second functional group includes one or more combinations of acrylate group, methacrylate group, epoxy group, amino group, and mercapto group.

5. The POSS-linkage based quantum dot photoresist composite of claim 2, wherein: At least one end of the functionalized POSS structural monomer also has a third functional group as a photopolymerization active group capable of participating in photopolymerization reaction; the third functional group is a functional group capable of absorbing light energy and producing active species or undergoing structural changes under light conditions, including one or more combinations of α-carbonyl group, acyl phosphine oxide group, photo-acid generating group, aromatic sulfonium salt or iodonium salt group, cinnamate group, chalcone group, azo group, aromatic conjugated light absorption group, and ultraviolet absorber type group; And / or, at least one end of the functionalized POSS structural monomer also has a fourth functional group, and the fourth functional group includes a hydrophilic group or a hydrophobic group, wherein the hydrophilic group includes one or more combinations of carboxyl, hydroxyl, amino, sulfonic acid, phosphonic acid, and polyether chain segment; and the hydrophobic group includes one or more combinations of alkyl, aromatic group, fluorine-containing alkyl, and siloxane chain segment.

6. The POSS-linkage based quantum dot photoresist composite of claim 1, wherein: The POSS structural monomer includes one or more combinations of a closed cage silsesquioxane, a partially open cage silsesquioxane, or a ladder silsesquioxane.

7. The POSS-linkage based quantum dot photoresist composite of claim 6, wherein: The POSS structural monomer is a polyhedral or quasi-polyhedral structure with a Si–O–Si inorganic skeleton.

8. The POSS-linkage based quantum dot photoresist composite of claim 7, wherein: The POSS structure monomers include one or more of a T8 type closed cage silsesquioxane, a T 10 type polyhedral silsesquioxane, a T 12 type polyhedral silsesquioxane, or a combination thereof.

9. The POSS-linkage based quantum dot photoresist composite of claim 8, wherein: The POSS structure monomer is a T8 type closed cage silsesquioxane containing 2-8 functional groups, and the functional groups are a combination of first, second, third and fourth functional groups, and the number ratio of the first, third and fourth functional groups is 1:1:0-4:2:

2.

10. The POSS-linked quantum dot photoresist composite of claim 1, wherein: A plurality of the POSS-quantum dot composite bodies are cross-linked with each other. Alternatively, the POSS connection-based quantum dot photoresist composite material further comprises a photoresist matrix, the POSS-quantum dot composite bodies are uniformly dispersed in the photoresist matrix, and the content of the POSS-quantum dot composite bodies in the POSS connection-based quantum dot photoresist composite material is 1-40 wt%, and the balance is the photoresist matrix.

11. The POSS-linked quantum dot photoresist composite of claim 1, wherein: The quantum dots include one or a combination of IV group quantum dots, II-VI group quantum dots, IV-VI group quantum dots and III-V group quantum dots. And / or, the content of the quantum dots in the POSS-quantum dot composite body is 5-50 wt%.

12. The method for preparing the quantum dot photoresist composite material based on POSS interconnection as described in any one of claims 1 to 11, characterized in that, It comprises: The quantum dots are connected to the POSS structure monomers by covalent bonds or coordination bonds to form POSS-quantum dot composite bodies; The POSS-quantum dot composite bodies are mixed, or the POSS-quantum dot composite bodies are mixed with a photoresist system to obtain a POSS connection-based quantum dot photoresist composite material.

13. A POSS-linked quantum dot photoresist composite material, characterized in that, It comprises: A composite host network framework formed by the combination of the POSS structure monomers and resin monomers, and quantum dots, wherein the quantum dots are uniformly embedded inside the composite host network framework to form a ternary hybrid network, the POSS structure monomers and the quantum dots are connected by covalent bonds or coordination bonds, and a dense coating layer is formed on the surface of the quantum dots; Alternatively, the quantum dots are directly mixed in a dispersed form between the composite host network frameworks.

14. The POSS-linker based quantum dot photoresist composite of claim 13, wherein: The resin monomers include one or a combination of methyl methacrylate, methyl acrylate, 2-hydroxyethyl methacrylate, n-butyl acrylate, isobornyl methacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, N-acryloyl morpholine and N-acryloyl morpholine derivatives.

15. The POSS-linker based quantum dot photoresist composite of claim 13, wherein: The POSS structure monomer is a functionalized POSS structure monomer connected to the surface metal ions of the quantum dots by coordination bonds or group substitution, at least one end of the functionalized POSS structure monomer has a first functional group as a ligand group for connection with the surface of the quantum dots, and the first functional group includes one or a combination of mercapto, carboxyl, amino, phosphonic acid, phosphine oxide, selenol, acrylate and epoxy groups.

16. The POSS-linker based quantum dot photoresist composite of claim 15, wherein: The functionalized POSS structure monomer is connected to the quantum dots with a first pre-modified ligand by coordination bonds or group substitution, and the first pre-modified ligand contains one or a combination of phosphonic acid, mercapto, selenol, carboxyl, acrylate and epoxy groups.

17. The POSS-linkage based quantum dot photoresist composite of claim 16, wherein: The quantum dot surface also has a second pre-modification ligand as an active end group, the second pre-modification ligand includes a combination of one or more of acrylic acid ligand, methacrylic acid ligand, epoxy ligand, isocyanate ligand, thiol ligand, amino ligand; at least one end of the functionalized POSS structure monomer also has a second functional group matched with the second pre-modification ligand, the second functional group includes a combination of one or more of acrylate group, methacrylate group, epoxy group, amino group, thiol group.

18. The POSS-linker based quantum dot photoresist composite of claim 15, wherein: At least one end of the functionalized POSS structure monomer also has a third functional group as a photopolymerization active group capable of participating in photopolymerization reaction; the third functional group is a functional group capable of absorbing light energy and generating active species or structural changes under light conditions, including a combination of one or more of α-carbonyl group, acyl phosphine oxide group, photo-acid generating group, aromatic sulfonium salt or iodonium salt group, cinnamate group, chalcone group, azo group, aromatic conjugated light absorption group, ultraviolet absorber type group; And / or, at least one end of the functionalized POSS structure monomer also has a fourth functional group, the fourth functional group includes a hydrophilic group or a hydrophobic group, wherein the hydrophilic group includes a combination of one or more of carboxyl group, hydroxyl group, amino group, sulfonic acid group, phosphonic acid group, polyether chain segment; the hydrophobic group includes a combination of one or more of alkyl group, aromatic group, fluorine-containing alkyl group, siloxane chain segment.

19. The POSS-linked quantum dot photoresist composite of claim 13, wherein: The POSS structure monomer includes a combination of one or more of closed cage silsesquioxane, partially open cage silsesquioxane or ladder silsesquioxane.

20. The POSS-linked quantum dot photoresist composite of claim 19, wherein: The POSS structure monomer is a polyhedral or quasi-polyhedral structure with a Si-O-Si inorganic skeleton.

21. The POSS-linked quantum dot photoresist composite of claim 20, wherein: The POSS structure monomers include one or more of a T8 type closed cage silsesquioxane, a T 10 type polyhedral silsesquioxane, a T 12 type polyhedral silsesquioxane, or a combination thereof.

22. The POSS-linked quantum dot photoresist composite of claim 21, wherein: The POSS structure monomer is a T8 type closed cage silsesquioxane containing 2-8 functional groups, the functional groups are a combination of the first functional group, the second functional group, the third functional group and the fourth functional group, and the number ratio of the first functional group, the third functional group and the fourth functional group is 1:1:0-4:2:

2.

23. The POSS-linker based quantum dot photoresist composite of claim 13, wherein: The quantum dot includes a combination of one or more of group IV quantum dots, group II-VI quantum dots, group IV-VI quantum dots, group III-V quantum dots; and / or, the content of quantum dots in the POSS connection-based quantum dot photoresist composite material is 0.1-50wt%, and the content of functionalized POSS structure monomer is 1-30wt%.

24. The method for preparing a quantum dot photoresist composite material based on POSS interconnection as described in any one of claims 13 to 23, characterized in that, It includes: Mixing the POSS structure monomer, the quantum dot, the resin monomer, the photoinitiator and the solvent uniformly to prepare the POSS connection-based quantum dot photoresist composite material; Or, first, the POSS structure monomer is compounded with the resin monomer to form a composite main network framework, and then the quantum dots are mixed in a dispersed form between the composite main network framework to prepare the POSS connection-based quantum dot photoresist composite material.

25. The method of claim 24, wherein: The photoinitiator includes a combination of one or more of TPO, Irgacure819 and BAPO; and / or, the solvent includes a combination of one or both of PGMEA and GBL.

26. The method of claim 24, wherein, It includes: The functionalized POSS structure monomer, quantum dots, resin monomer, photoinitiator and solvent are mixed to form a mixed solution, and the mixed solution is magnetically stirred for 30-180 min to prepare a quantum dot photoresist composite material based on POSS connection. In the mixed solution, the content of the functionalized POSS structure monomer is 1-20 wt%, the content of the quantum dots is 0.1-50 wt%, the content of the resin monomer is 50-90 wt%, the content of the photoinitiator is 0.1-5 wt%, and the balance is the solvent. And / or, the mixed solution further comprises an auxiliary agent, and the auxiliary agent comprises a combination of one or both of a diluent and a surface agent.

27. A method of patterning quantum dots, the method comprising: It comprises: The quantum dot photoresist composite material based on POSS connection according to any one of claims 1-11 and 13-23 is applied to the surface of a Micro-LED chip; Patterned exposure is performed by mask exposure, laser scanning or TPP; After development, a patterned quantum dot pattern of the corresponding color is obtained.

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