Preparation method of controllable large-area three-color quantum dot micro-nano array

Abstract

The application provides a controllable large-area three-color quantum dot micro-nano array preparation method, which comprises the following steps: regularly jetting different color quantum dot arrays on the surface of a target substrate, using a printing template with an asymmetric wetting micro-column array, and combining with a liquid bridge dewetting growth technology to prepare a large-area micro-nano array with red, green and blue colors arranged alternately. The application can improve the preparation efficiency and product quality; no additive needs to be added in the preparation process, thereby reducing the influence on the later-stage electric injection device; the device preparation process has high repeatability, the template does not need to be repeatedly prepared, and the cost is saved; the application has strong universality, different shape templates can be prepared to obtain different patterned micro-nano structures, and the application is suitable for different solutions; the application can be prepared on a large scale, thereby solving the problem that the traditional technology cannot be prepared on a large scale. The application realizes the preparation of the three primary color quantum dot arrays arranged alternately on different substries in a controllable manner, is expected to realize large-scale industrial production, and provides a new solution for the design and manufacture of display devices on a large scale.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of basic electrical elements, in particular to a controllable large-area three-color quantum dot micro-nano array preparation method. BACKGROUND

[0002] With the rapid development of the display industry, colloidal quantum dots have been widely concerned due to their good tunability, narrow band gap, high luminescent efficiency and other advantages. Common displays are mainly composed of a plurality of pixel arrays, and each unit pixel is composed of sub-pixels including red, green and blue three primary colors. At present, different methods can be used to manufacture three primary color pixel arrays, such as photolithography, inkjet printing, transfer printing, etc. However, three primary color photoluminescence devices based on quantum dots cannot be precisely prepared in large area, and cross contamination between quantum dots is also the main reason limiting their development.

[0003] The traditional preparation method of photolithography has a relatively complex processing process, or the prepared device mostly contains organic additives, which can reduce the charge injection efficiency of quantum dots and is not conducive to the integration of the device in the later stage. Therefore, there is an urgent need for a simple, low-cost and large-scale method for preparing high-quality three primary color quantum dot arrays. SUMMARY

[0004] The present application is to solve the problem of preparing high-purity three primary color quantum dot arrays, and provides a controllable large-area three-color quantum dot micro-nano array preparation method. By regularly inkjet printing different color quantum dot arrays on the surface of the target substrate, using a printing template with an asymmetric wetting micro-pillar array, and combining the existing liquid bridge dewetting growth technology, a large-area red-green-blue alternating micro-nano array on the target substrate can be prepared.

[0005] The present application provides a controllable large-area three-color quantum dot micro-nano array preparation method, comprising the following steps:

[0006] S1, inkjet printing: injecting a printing solution into an inkjet printer, and performing inkjet printing on a substrate to obtain a quantum dot droplet array, the number of rows of the quantum dot droplet array being L;

[0007] S2, liquid bridge dewetting: moving the printing template and / or the substrate so that the surface of the micro-pillar of the printing template stays above the lth row of the quantum dot droplet array to obtain a sandwich-like structure, l initially being 1, the surface of the micro-pillar being hydrophilic and the sidewall being hydrophobic, the sandwich-like structure allowing liquid bridge dewetting, after staying for t 停 time, obtaining the lth row of quantum dot micro-nano array;

[0008] S3, continue liquid bridge dewetting: l=l+1, return to step S2, until l=L, and the quantum dot micro-nano array preparation is completed.

[0009] The preparation method of the controllable large-area three-color quantum dot micro-nano array, as a preferred mode, controls the time t0 of printing a row of quantum dot droplet arrays by the inkjet printer, the moving time t 转 and the staying time t 停 The quantum dot micro-nano array preparation process is continuous.

[0010] The preparation method of the controllable large-area three-color quantum dot micro-nano array, as a preferred mode, in step S1, the printing solution includes a red droplet printing solution, a green droplet printing solution and a blue droplet printing solution, the print head of the inkjet printer includes a red print head, a green print head and a blue print head, the red droplet printing solution is injected into the red print head, the green droplet printing solution is injected into the green print head, and the blue droplet printing solution is injected into the blue print head, the red print head, the green print head and the blue print head are arranged in three rows and simultaneously perform inkjet printing on the substrate to obtain a column of three-color quantum dot droplet arrays.

[0011] The quantum dot spectrum of the red droplet printing solution is 610nm-640nm, the quantum dot spectrum of the green droplet printing solution is 201nm-540nm, the quantum dot spectrum of the blue droplet printing solution is 455nm-490nm, and the solvent of the printing solution is any one of the following: perovskite, quantum dot, organic small molecule and polymer.

[0012] The preparation method of the controllable large-area three-color quantum dot micro-nano array, as a preferred mode, in step S1, the solvent of the printing solution is a n-hexane dispersion solution of 5-30mg / ml CdSe / ZnS quantum dots.

[0013] The preparation method of the controllable large-area three-color quantum dot micro-nano array, as a preferred mode, in step S2, the printing template is a cylinder with K rows of micro columns arranged on the surface, the printing template can rotate along the central axis of the cylinder, K is a multiple of 3, the number of micro columns in each row is the same as the number of quantum dot droplet arrays in each row, and the rotatable printing template is arranged above the substrate.

[0014] The substrate and / or the inkjet printer can be freely moved.

[0015] The preparation method of the controllable large-area three-color quantum dot micro-nano array, as a preferred mode, in step S1, the time of the inkjet printer printing a column of three-color quantum dot droplet arrays is t0.

[0016] In step S2, the printing template is moved so that the micro column surface of the printing template stays above the red quantum dot droplet array of the 11th row of three-color quantum dot droplet arrays to obtain a sandwich-like structure, and 11 is initially 1, and when t Rn0=t0+t 转 At that time, the red quantum dot droplet array began to enter the liquid bridge dewetting process, t Rn0 t is the moment when the red quantum dot droplet begins to dewetting. 转 t represents the time it takes for the micropillar to rotate to the next row of quantum dot droplet array. 转 Including the rotation time of the micropillar and the movement time of the substrate, after t 停 After time, i.e., t Rn At time 2t0, the red quantum dot micro-nano array of the l1th tricolor quantum dot droplet array is obtained;

[0017] When t Gn0 =2t0+t 转 At that time, the green quantum dot droplet array of the 11th tricolor quantum dot droplet array began to enter the dewetting process. Gn0 The moment when the green quantum dot droplets begin to dewetting, after t 停 After time, i.e., t Gn When =3t0, a green quantum dot micro / nano array of the l1st tricolor quantum dot droplet array is obtained;

[0018] When t Bn0 =3t0+t 转 At that time, the blue quantum dot droplet array of the l1st tricolor quantum dot droplet array began to enter the dewetting process. Bn0 The moment when the blue quantum dot droplets begin to dewetting, after t 停 After time, i.e., t Bn =t Gn At +t0, the blue quantum dot micro-nano array of the l1st tricolor quantum dot droplet array is obtained;

[0019] In step S3, l1 = l1 + 1, the inkjet printer continues printing to obtain the l1th column of the three-color quantum dot droplet array, and returns to step S2 until l1 = L / 3, and the preparation of the three-color quantum dot micro-nano array is completed.

[0020] In the controllable large-area three-color quantum dot micro / nano array fabrication method of the present invention, as a preferred embodiment, in steps S2 and S3, the dewetting temperature of the red quantum dot droplet array, the green quantum dot droplet array, and the blue quantum dot droplet array is 20-25°C.

[0021] In the controllable large-area three-color quantum dot micro / nano array fabrication method of the present invention, as a preferred embodiment, in step S1, the solvent of the printing solution is any one of the following: perovskite, quantum dots, small organic molecules, and polymers;

[0022] In steps S2 and S3, the dewetting temperature is adjusted according to the type of solvent.

[0023] As a preferred mode, in step S2, the printing template is prepared by a photolithography method, the micro column is a cylindrical structure, the printing template is modified by a modification liquid to make the top of the micro column hydrophilic and the sidewall hydrophobic, the modification liquid is any one of fluorosilane, octadecyltrichlorosilane and perfluorodecyltrichlorosiloxane, and the carbon chain length and halogen atom of the modification liquid are adjustable.

[0024] The micro column can be arranged in the following pattern arrays: straight line array, curved line array, circular array, square array and triangular array.

[0025] The substrate and / or inkjet printer can move back and forth.

[0026] As a preferred mode, the height of the micro column is 20 mu m, and the number of micro columns in each row is the same as the number of quantum dot droplet arrays in each row.

[0027] The application provides a controllable large-area three-color quantum dot micro-nano array preparation method, which combines inkjet printing technology and liquid bridge growth technology, obtains a sandwich-like structure, and is treated at different temperatures to obtain a three-color pixel array; the method for preparing a patterned printing template is as follows: a photolithography technology is used to obtain a printing template with a micro-nano structure; and the method for asymmetric wettability treatment is as follows: fluorosilane is used to prepare a micro column array template with a hydrophilic top and a hydrophobic sidewall.

[0028] The method combines the advantages of liquid bridge growth and inkjet printing, can accurately control the array color and pattern, can prepare a three-primary-color long-range ordered semiconductor array by designing a one-dimensional linear template, can obtain high-quality single-oriented micro-nano crystals and densely packed quantum dot structures through wettability induction, uses pure quantum dot solution in the preparation process, is not affected by organic additives, and can accurately prepare a target number of micro-nano arrays by accurately controlling the rotation speed, substrate speed and inkjet printing speed.

[0029] The technical solution is suitable for most soluble materials, has good universality, can effectively dissolve materials meeting the conditions using different solvents, can freely design patterns and sizes to obtain different types of patterned arrays, has the potential for large-scale integrated production, breaks through the area size limitation of the original liquid phase method, can prepare larger-area micro-nano arrays using the same template, is not limited to preparing different color arrays, and can effectively expand the array area and quality for the same material.

[0030] The technical solution of the application is as follows:

[0031] 1) Preparation of micro-pillar printing template with specific shape: using photolithography technique, a printing template with micro-pillar structure is obtained, and in this technical solution, each column has 9 columns of micro-pillars, and each column includes 5 micro-pillar models as an example.

[0032] 2) Asymmetric wetting treatment: using fluorosilane modification method, a micro-pillar surface with asymmetric wetting is prepared, the top of the silicon column has hydrophilicity, and the sidewall of the micro-pillar has hydrophobicity.

[0033] Assuming that the initial droplet position is different from the de-wetting starting position by ma0(a0 is the sum of the diameter of the silicon column and the array pitch; t 转 is the template rotation and substrate movement time, t 停 is the de-wetting time) When m=2, the red droplet reaches the de-wetting starting position after (t0+t 转 ) time.

[0034] 3) Three-color droplet printing: starting from t=0, when t=3lt0, a three-primary-color quantum dot droplet array is obtained by using inkjet printing method until the required array number is completed (l=0, 1, 2, 3…);

[0035] When the n=1th cycle (n=1, 2, 3…)

[0036] 4) Red droplet de-wetting: when t Rn0 =t0+t 转 , the red droplet enters the de-wetting process, and due to the asymmetric modification of the silicon column surface, the quantum dot solution preferentially de-wets at the top of the silicon column, and after t 停 time, i.e. t Rn =2t0, the red quantum dot array completes the de-wetting process.

[0037] 5) Green droplet de-wetting: when t Gn0 =2t0+t 转 , the green droplet enters the de-wetting process, and due to the asymmetric modification of the silicon column surface, the quantum dot solution preferentially de-wets at the top of the silicon column, and after t 停 time, i.e. t Gn =3t0, the green quantum dot array completes the de-wetting process.

[0038] 6) Blue droplet de-wetting: when t Bn0 =3t0+t 转 , the blue droplet enters the de-wetting process, and due to the asymmetric modification of the silicon column surface, the quantum dot solution preferentially de-wets at the top of the silicon column, and after t 停 time, i.e. t Bn =t Gn +t0, the blue quantum dot array completes the de-wetting process.

[0039] 7) Repeat steps 4)-6) until the desired number of arrays is completed.

[0040] Wherein, the microcolumn depth obtained by the photolithography template in step 1) is 20 μm.

[0041] Wherein, the microstructure template pattern of the photolithography in step 1) is adjustable.

[0042] Wherein, the number of microcolumn structure templates of the photolithography in step 1) is adjustable.

[0043] Wherein, the structure template of the photolithography in step 1) can be set as one-dimensional linear.

[0044] Wherein, the fluoroalkylsilane in step 2) is perfluorodecyltriethoxysilane, modified in a vacuum dryer at 90℃, and the reaction time is 2 h.

[0045] Wherein, the solution used in step 3) is a 10 mg / ml CdSe / ZnS quantum dot dispersion solution in n-hexane.

[0046] Wherein, the spectrum of the CdSe / ZnS quantum dots used in step 3) is 460 nm 540 nm 620 nm.

[0047] Wherein, the material used in step 3) is not limited to CdSe / ZnS n-hexane solution, and is suitable for most solution-processed materials, including but not limited to perovskite, quantum dots, organic small molecules, polymers, etc.

[0048] Wherein, if the solution used in step 3) is the same material, steps 4)-6) are the same process, and the obtained array is a large-area array of the same material.

[0049] Wherein, the solution immersion process temperature in steps 4)-6) should be room temperature 20-25℃, and should not exceed 30℃, to avoid defects on the surface of the micro-nano array due to too fast immersion process.

[0050] Wherein, the solution immersion process temperature in steps 4)-6) can be adjusted according to the different solutions used, and the same effect can be achieved.

[0051] The printing solution can be an RGB three-color solution, or other three different color solutions, including but not limited to small molecule crystal solution, organic solution, polymer solution, etc.; the color type can exceed three, and theoretically any number of color uniform arrays can be obtained; for the same material, the array area and quality can be effectively expanded.

[0052] The present application has the following advantages:

[0053] The present application combines the existing liquid bridge processing technology and inkjet printing technology to improve the preparation efficiency and product quality; no additive is added in the preparation process, which reduces the influence on the later-stage electric injection device; the device preparation process has high repeatability, does not need to repeatedly prepare a template, and saves cost; it has strong universality, can prepare different shape templates to obtain different patterned micro-nano structures, and is suitable for different solutions. It can be prepared on a large scale, solving the problem that traditional technology cannot be prepared on a large scale. The present application realizes the accurate preparation of three-primary-color alternating quantum dot arrays on different substrates, and is expected to realize large-scale industrial production, providing a new solution for designing and manufacturing display devices on a large scale. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 A controllable large-area three-color quantum dot micro-nano array preparation method flow chart;

[0055] Figure 2 A controllable large-area three-color quantum dot micro-nano array preparation method equipment structure schematic diagram;

[0056] Figure 3 A controllable large-area three-color quantum dot micro-nano array preparation method step S1 droplet printing process schematic diagram;

[0057] Figure 4 A controllable large-area three-color quantum dot micro-nano array preparation method step S2 red array preparation process schematic diagram;

[0058] Figure 5 A controllable large-area three-color quantum dot micro-nano array preparation method step S2 green array preparation process schematic diagram;

[0059] Figure 6 A controllable large-area three-color quantum dot micro-nano array preparation method step S2 blue array preparation process schematic diagram;

[0060] Figure 7 A controllable large-area three-color quantum dot micro-nano array preparation method preparation completion schematic diagram;

[0061] Figure 8 A controllable large-area three-color quantum dot micro-nano array preparation method three-primary-color quantum dot micro-nano array model diagram.

[0062] REFERENCE NUMERALS:

[0063] 1, inkjet printer; 2, substrate; 3, printing template. DETAILED DESCRIPTION

[0064] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0065] Example 1

[0066] like Figures 1-2 As shown, a method for fabricating a controllable large-area three-color quantum dot micro / nano array includes the following steps:

[0067] S1. Inkjet printing: A printing solution is injected into inkjet printer 1, and inkjet printer 1 performs inkjet printing on substrate 2 to obtain a quantum dot droplet array. The number of rows in the quantum dot droplet array is L.

[0068] The printing solution includes a red droplet printing solution, a green droplet printing solution, and a blue droplet printing solution. The printhead of the inkjet printer 1 includes a red printhead, a green printhead, and a blue printhead. The red droplet printing solution is injected into the red printhead, the green droplet printing solution is injected into the green printhead, and the blue droplet printing solution is injected into the blue printhead. The red printhead, the green printhead, and the blue printhead are arranged in three rows and inkjet printing is performed simultaneously on the substrate 2 to obtain a column of three-color quantum dot array.

[0069] The quantum dot spectrum of the solution used for red droplet printing is 610 nm to 640 nm, the quantum dot spectrum of the solution used for green droplet printing is 201 nm to 540 nm, and the quantum dot spectrum of the solution used for blue droplet printing is 455 nm to 490 nm. The solvent of the printing solution can be any of the following: perovskite, quantum dots, small organic molecules, and polymers.

[0070] The solvent for the printing solution is a hexane dispersion of 5–30 mg / ml CdSe / ZnS quantum dots;

[0071] The time it takes for inkjet printer 1 to print a column of three-color quantum dot droplet arrays is t0;

[0072] The solvent for the printing solution can be any of the following: perovskite, quantum dots, small organic molecules, and polymers;

[0073] S2, Liquid Bridge De-wetting: (e.g., ...) Figure 3 As shown, the printing template 3 and / or substrate 2 are moved so that the surface of the micropillars of the printing template 3 rests above the quantum dot droplet array in the l-th row, resulting in a sandwich-like structure. Initially, l is 1. The surface of the micropillars is hydrophilic, and the sidewalls are hydrophobic. The sandwich-like structure causes the liquid bridges to dewet. At rest for t... 停 After a certain period of time, the l-th row of quantum dot micro / nano arrays was obtained;

[0074] The printing template 3 is a cylinder with K rows of micropillars on its surface. The printing template 3 can rotate along the central axis of the cylinder. K is a multiple of 3. The number of micropillars in each row is the same as the number of quantum dot droplet arrays in each row. The printing template 3 is rotatably and movable above the substrate 2.

[0075] The substrate 2 and / or inkjet printer 1 can move freely;

[0076] like Figures 4-6 As shown, the printing template 3 is moved so that the surface of the micropillars of the printing template 3 rests above the red quantum dot droplet array of the three-color quantum dot droplet array in row l1, resulting in a sandwich-like structure. l1 is initially 1, and when t... Rn0 =t0+t 转 At that time, the red quantum dot droplet array began to enter the liquid bridge dewetting process, t Rn0 t is the moment when the red quantum dot droplet begins to dewetting. 转 t represents the time it takes for the micropillar to rotate to the next row of quantum dot droplet array. 转 Including the rotation time of the micropillar and the movement time of the substrate 2, after t 停 After time, i.e., t Rn At time 2t0, the red quantum dot micro-nano array of the l1th tricolor quantum dot droplet array is obtained;

[0077] When t Gn0 =2t0+t 转 At that time, the green quantum dot droplet array of the l1st tricolor quantum dot droplet array began to enter the dewetting process. Gn0 The moment when the green quantum dot droplets begin to dewetting, after t 停 After time, i.e., t Gn When =3t0, a green quantum dot micro / nano array of the l1st tricolor quantum dot droplet array is obtained;

[0078] When t Bn0 =3t0+t 转 At that time, the blue quantum dot droplet array of the l1st tricolor quantum dot droplet array began to enter the dewetting process. Bn0 The moment when the blue quantum dot droplets begin to dewetting, after t 停 After time, i.e., t Bn =t Gn At +t0, the blue quantum dot micro-nano array of the l1st tricolor quantum dot droplet array is obtained;

[0079] The printing template 3 is prepared by photolithography. The micropillar has a cylindrical structure. The printing template 3 is modified with a modification liquid to make the top of the micropillar hydrophilic and the sidewall hydrophobic. The modification liquid can be any one of the following: fluorosilane, octadecyltrichlorosilane and perfluorodecyltrichlorosiloxane. The carbon chain length and halogen atom of the modification liquid can be adjusted.

[0080] Micropillars can be arranged in the following pattern arrays: linear array, curved array, circular array, square array, and triangular array;

[0081] The substrate 2 and / or inkjet printer 1 can move back and forth;

[0082] The height of the micropillars is 20 μm, and the number of micropillars in each row is the same as the number of quantum dot droplet arrays in each row.

[0083] S3. Continue liquid bridge de-wetting: l = l + 1, return to step S2, until l = L, as shown. Figures 7-8 As shown, the quantum dot micro / nano array has been successfully fabricated.

[0084] By controlling the printing time t0 of a line of quantum dot droplet array printed by inkjet printer 1 and the moving time t of printing template 3, 转 The dwell time t of printing template 3 停 This enables the continuous fabrication process of quantum dot micro / nano arrays.

[0085] l1 = l1 + 1, inkjet printer 1 continues printing to obtain the l1th column of the three-color quantum dot droplet array, return to step S2, until l1 = L / 3, the three-color quantum dot micro-nano array is prepared;

[0086] In steps S2 and S3, the dewetting temperature of the red quantum dot droplet array, the green quantum dot droplet array, and the blue quantum dot droplet array is 20–25°C.

[0087] In steps S2 and S3, the dewetting temperature is adjusted according to the type of solvent.

[0088] Example 2

[0089] like Figures 1-2 As shown, a controllable large-area three-color quantum dot micro / nano array fabrication method combines superwetting self-assembly technology with inkjet printing technology. First, a micro / nano array printing template 3 with a specific pattern is prepared. Then, superhydrophobic modification with fluorosilane is performed to obtain a micropillar surface with asymmetric wettability. By precisely controlling the rotation rate of the micro-template 3, the movement rate of the substrate 2, and the inkjet printing rate 1, the large-area precise fabrication of a three-color quantum dot micro / nano array is achieved. The specific steps are as follows:

[0090] 1) Using photolithography, a printing template 3 with a micropillar structure is obtained. This technical solution takes a cylinder with 9 columns of micropillars and each column with 5 micropillar models as an example.

[0091] 2) Place the microcolumn template 3 and 10 ml of perfluorodecyltriethoxysilane FAS in a vacuum desiccator for asymmetric modification and keep at 90℃ for 2 h.

[0092] Assume the initial droplet position differs from the dewetting initiation position by ma0 (a0 is the sum of the silicon pillar diameter and the array spacing, where a0 is 10 μm; t 转 t represents the time for template 3 to rotate and base 2 to move. 停 (For the time of immersion) When m=2, then after (t0+t) 转 (Time) When the red droplet reaches the dewetting initiation position, t0 = t 停 +t 转 .

[0093] 3) such as Figure 3 As shown, a CdSe / ZnS quantum dot solution with spectra located at 460nm, 540nm, and 620nm, at a concentration of 10mg / ml, was dispersed in n-hexane solvent and injected into an inkjet printer. Starting from t=0, when t=3lt0, a three-primary-color quantum dot droplet array was obtained by inkjet printing until the required array number (l=0,1,2,3…) was completed.

[0094] When the n=1th iteration occurs (n=1,2,3…)

[0095] 4) such as Figure 4 As shown, the red droplet dewetting occurs when t Rn0 =t0+t 转 At that time, the red droplet enters the dewetting process. Due to the asymmetric modification of the silicon pillar surface, the quantum dot solution preferentially undergoes dewetting at the top of the silicon pillar. After t 停 After time, i.e., t Rn At time 2t0, the red quantum dot array completes the dewetting process.

[0096] 5) such as Figure 5 As shown, the green droplets dewetting occurs when t Gn0 =2t0+t 转 At that time, the green droplets enter the dewetting process. Due to the asymmetric modification of the silicon pillar surface, the quantum dot solution preferentially undergoes dewetting at the top of the silicon pillar. After t 停 After time, i.e., t Gn At time 3t0, the green quantum dot array completes the dewetting process.

[0097] 6) such as Figure 6 As shown, the blue droplet dewetting occurs when t Bn0 =3t0+t 转 At that time, the blue droplets entered the dewetting process. Due to the asymmetric modification of the silicon pillar surface, the quantum dot solution preferentially underwent dewetting at the top of the silicon pillar. After t 停 After time, i.e., t Bn =t Gn At time +t0, the blue quantum dot array completes the dewetting process.

[0098] 7) Repeat steps 4) - 6) until the desired number of arrays is complete, such as Figures 7-8 as shown,

[0099] R:start t Rn0 = (3n - 3)to + (m - 1)to + t 转 end t Rn = (3n - 2)to + (m - 1)to;

[0100] G:start t Gn0 = (3n - 2)to + (m - 1)to + t 转 end t Gn = (3n - 1)to + (m - 1)to;

[0101] B:start t Bn0 = (3n - 1)to + (m - 1)to + t 转 end t Gn = 3nto + (m - 1)to.

[0102] The quantum dot solution in the embodiment can be an RGB three-color solution, or other three different color solutions, including but not limited to small molecule crystal solution, organic solution, polymer solution, etc.; the color types can be more than three, and theoretically, a uniform array of any number of colors can be obtained; for the same material, the array area and quality can be effectively enlarged.

[0103] The above merely provides the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art, according to the technical scheme and the inventive concept of the present application, can make equivalent replacement or change within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A method for preparing a controllable large-area three-color quantum dot micro-nano array, characterized in that: The method comprises the following steps: S1, inkjet printing: injecting a printing solution into an inkjet printer (1), and performing inkjet printing on a substrate (2) to obtain a quantum dot droplet array, the number of rows of the quantum dot droplet array being L; S2, liquid bridge de-wetting: moving the printing template (3) and / or the substrate (2) so that the micro-pillar surface of the printing template (3) stays above the quantum dot droplet array of the lth row, obtaining a sandwich-like structure, l is initially 1, the surface of the micro-pillar is hydrophilic and the sidewall is hydrophobic, the sandwich-like structure causes liquid bridge de-wetting, after staying for t 停 time, obtaining a quantum dot micro-nano array of the lth row; S3, continue liquid bridge dewetting: l = l + 1, return to step S2 until l = L, and the preparation of the quantum dot micro-nano array is completed.

2. The method for fabricating a controllable large-area three-color quantum dot micro / nano array according to claim 1, characterized in that: by controlling the time t0 of printing a line of the array of quantum dot droplets by the inkjet printer (1), the time t of movement of the printing template (3) 转 and the time t of dwell of the printing template (3) 停 to make the process of preparation of quantum dot micro- and nano-arrays continuous. 3.The method of claim 1, wherein the method further comprises: controlling the quantum dot micro-nano array to emit red, green, and blue light. In step S1, the printing solution comprises a red droplet printing solution, a green droplet printing solution and a blue droplet printing solution, the print head of the inkjet printer (1) comprises a red print head, a green print head and a blue print head, the red droplet printing solution is injected into the red print head, the green droplet printing solution is injected into the green print head, and the blue droplet printing solution is injected into the blue print head, the red print head, the green print head and the blue print head are arranged in three rows to perform inkjet printing on the substrate (2) at the same time to obtain a three-color quantum dot droplet array in a row; The quantum dot spectrum of the red droplet printing solution is 610nm-640nm, the quantum dot spectrum of the green droplet printing solution is 201nm-540nm, the quantum dot spectrum of the blue droplet printing solution is 455nm-490nm, and the solvent of the printing solution is any one of the following: perovskite, quantum dot, organic small molecule and polymer.

4. The method according to claim 3, wherein the method is characterized by: In step S1, the solvent of the printing solution is a n-hexane dispersion solution of 5-30mg / ml CdSe / ZnS quantum dots.

5. The method according to claim 3, wherein the method is characterized by: In step S2, the printing template (3) is a cylinder with K rows of micro columns arranged on the surface, the printing template (3) can rotate along the central axis of the cylinder, K is a multiple of 3, the number of micro columns in each row is the same as the number of quantum dot droplet arrays in each row, and the printing template (3) is arranged above the substrate (2) and can rotate and move. The substrate (2) and / or the inkjet printer (1) can move freely.

6. The method according to claim 3, wherein the method is characterized by: In step S1, the inkjet printer (1) prints a row of the three-color quantum dot droplet array in time t0. In step S2, the printing template (3) is moved so that the microcolumn surface of the printing template (3) is above the red quantum dot droplet array of the l1th row of the three-color quantum dot droplet array, to obtain the sandwich-like structure, where l1 is initially 1, and when t Rn0 =t0+t 转 , the red quantum dot droplet array starts to enter the liquid bridge de-wetting process, t Rn0 is the time when the red quantum dot droplet starts to de-wet, t 转 is the time for the microcolumn to rotate to the next row of quantum dot droplet array, t 转 includes the rotation time of the microcolumn and the moving time of the substrate (2), and after t 停 time, that is, t Rn =2t0, the red quantum dot micro-nano array of the l1th three-color quantum dot droplet array is obtained. When t Gn0 = 2t0+ t 转 , the green quantum dot droplet array of the 11th three-color quantum dot droplet array begins to enter the de-wetting process, t Gn0 is the time when the green quantum dot droplet begins to de-wet, and after t 停 time, that is, t Gn = 3t0, the green quantum dot micro-nano array of the 11th three-color quantum dot droplet array is obtained. When t Bn0 = 3t0+t 转 , the blue quantum dot droplet array of the 11th three-color quantum dot droplet array begins to enter the de-wetting process, t Bn0 is the time when the blue quantum dot droplet begins to de-wet, and after t 停 time, that is, t Bn = t Gn +t0, the blue quantum dot micro-nano array of the 11th three-color quantum dot droplet array is obtained. In step S3, l1 = l1 + 1, the inkjet printer (1) continues to print to obtain the l1th row of the three-color quantum dot droplet array, and returns to step S2 until l1 = L / 3, and the preparation of the three-color quantum dot micro-nano array is completed.

7. The method according to claim 6, wherein the method is characterized by: In steps S2 and S3, the dewetting temperature of the red quantum dot droplet array, the green quantum dot droplet array and the blue quantum dot droplet array is 20-25℃. 8.The method of claim 1, wherein the method is characterized by: In step S1, the solvent of the printing solution is any one of the following: perovskite, quantum dot, organic small molecule and polymer; In steps S2 and S3, the dewetting temperature is adjusted according to the type of the solvent.

9. The method according to claim 1, wherein the method is characterized by: In step S2, the printing template (3) is prepared by a photolithography method, the micro-column is a cylindrical structure, and the printing template (3) is modified by using a modification liquid to make the top end of the micro-column have hydrophilicity and the sidewall have hydrophobicity, the modification liquid is any one of fluorosilane, octadecyltrichlorosilane and perfluorodecyltrichlorosilane, and the carbon chain length and halogen atom of the modification liquid are adjustable. The micro-column can be arranged in a pattern array as follows: a straight line array, a curved line array, a circular array, a square array and a triangular array. The substrate (2) and / or the inkjet printer (1) can move forward and backward.

10. The method according to claim 9, wherein the method is characterized by: The height of the micro-column is 20 μm, and the number of micro-columns in each row is the same as the number of quantum dot liquid drop arrays in each row.

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