Light-emitting structure and preparation method thereof

Abstract

The invention provides a light-emitting structure and a preparation method thereof. A miniature light-emitting diode chip of the light-emitting structure comprises a plurality of pixel units; the hydrophobic layer is arranged on one side of the micro light emitting diode chip, the hydrophobic layer comprises a hydrophobic area and a hydrophilic area, and the hydrophobic area and the hydrophilic area both cover at least one pixel unit; the micro lens array comprises a plurality of micro lens units arranged in one-to-one correspondence with the plurality of pixel units, and the plurality of micro lens units are formed on the surface, away from the micro light-emitting diode chip, of the hydrophobic layer. On the basis, the invention provides a scheme for forming different patterns by the micro lens array, so that the micro light-emitting diode chip has richer display performance.

Description

Technical Field

[0001] This application relates to the field of semiconductor light-emitting technology, specifically to a light-emitting structure and its preparation method. Background Technology

[0002] Micro-LED (Micro-Light Emitting Diode) display technology miniaturizes and arrays the traditional LED (Light Emitting Diode) structure, and uses CMOS (Complementary Metal Oxide Semiconductor) or TFT (Thin Film Transistor) to create the driving circuit, thereby achieving addressing control and individual driving of each pixel structure.

[0003] Because red and green quantum dots have different light-emitting characteristics than blue pixels, full-color Micro-LED display modules suffer from color bias at large viewing angles, resulting in poor display quality and room for improvement. Summary of the Invention

[0004] The purpose of this application is to provide a light-emitting structure and a method for preparing the same.

[0005] To address the aforementioned problems, firstly, this application provides a light-emitting structure, comprising:

[0006] A miniature light-emitting diode chip, comprising multiple pixel units;

[0007] A hydrophobic layer is disposed on the light-emitting side of the micro LED chip. The hydrophobic layer includes a hydrophobic region and a hydrophilic region, and both the hydrophobic region and the hydrophilic region cover at least one pixel unit.

[0008] The microlens array includes multiple microlens units that are arranged one-to-one with the multiple pixel units, and the multiple microlens units are formed on the side of the hydrophobic layer facing away from the micro light-emitting diode chip.

[0009] Optionally, the microlens array includes a first microlens unit corresponding to the hydrophobic region and a second microlens unit corresponding to the hydrophilic region, wherein the height of the second microlens unit is less than the height of the first microlens unit, and the width of the second microlens unit is greater than or equal to the width of the first microlens unit.

[0010] Optionally, the microlens array includes a first microlens unit corresponding to the hydrophobic region and a second microlens unit corresponding to the hydrophilic region, wherein the radius of curvature of the first microlens unit is less than or equal to the radius of curvature of the second microlens unit.

[0011] Optionally, the light-emitting structure further includes:

[0012] A color conversion layer is disposed between the micro LED chip and the hydrophobic layer. The color conversion layer includes a color conversion region and a light-transmitting region. The hydrophobic region covers the color conversion region, and the hydrophilic region covers the light-transmitting region. The color conversion region is used to convert the emission color of the pixel unit it covers, and the light-transmitting region is used to transmit the emission color of the pixel unit it covers.

[0013] Optionally, each of the plurality of pixel units is used to emit light of a first color, and the color conversion region is provided with a first quantum dot structure and a second quantum dot structure. The first quantum dot structure is used to convert the pixel units it covers into light of a second color, and the second quantum dot structure is used to convert the pixel units it covers into light of a third color. The first color, the second color, and the third color are all different.

[0014] Secondly, this application also provides a method for preparing a light-emitting structure, comprising:

[0015] A hydrophobic layer is formed on the light-emitting side of a micro LED chip, the hydrophobic layer comprising a hydrophobic region and a hydrophilic region; the micro LED chip comprises multiple pixel units, and both the hydrophobic region and the hydrophilic region cover at least one pixel unit;

[0016] Multiple microlens units are formed on the side of the hydrophobic layer facing away from the micro LED chip, and the multiple microlens units are arranged in a one-to-one correspondence with the multiple pixel units to form a light-emitting structure.

[0017] Optionally, a hydrophobic layer is formed on the light-emitting side of the micro-LED chip, the hydrophobic layer comprising hydrophobic regions and hydrophilic regions, including:

[0018] A hydrophobic structure and a hydrophobic layer are formed on the light-emitting side of the micro LED chip;

[0019] A photoresist layer is formed on the side of the hydrophobic structure facing away from the micro LED chip;

[0020] An opening region communicating with the hydrophobic layer is formed in the region of the photoresist layer corresponding to at least one pixel unit;

[0021] A localized oxygen plasma modification process is performed in the opening region to form a hydrophilic region on the hydrophobic layer;

[0022] Remove the photoresist layer from other areas and form a hydrophobic region on the hydrophobic layer.

[0023] Optionally, the step of performing local oxygen plasma modification in the opening region and forming a hydrophilic region on the hydrophobic layer includes:

[0024] A reactive ion etching process or an inductively coupled plasma process is performed in the opening region to form a hydrophilic region on the hydrophobic layer.

[0025] Optionally, the formation of multiple microlens units on the side of the hydrophobic layer opposite to the micro-LED chip includes:

[0026] Photolithography and thermal reflow processes are performed on the side of the hydrophobic layer opposite to the micro LED chip to form multiple microlens units.

[0027] Optionally, forming a hydrophobic layer on the light-emitting side of the micro-LED chip includes:

[0028] A hydrophobic layer is formed on the side of the color conversion layer facing away from the micro LED chip. The color conversion layer includes a color conversion region and a light-transmitting region. The hydrophobic region covers the color conversion region, and the hydrophilic region covers the light-transmitting region. The color conversion region is used to convert the emission color of the pixel unit it covers, and the light-transmitting region is used to transmit the emission of the pixel unit it covers.

[0029] Based on the above technical solution, the microlens array of the light-emitting structure provided in this application has multiple microlens units formed on the side of the hydrophobic layer facing away from the micro-light-emitting diode chip. Since the hydrophobic layer includes hydrophobic and hydrophilic regions, the microlens units formed in the hydrophobic region and the microlens units formed in the hydrophilic region can form microlens structures of different shapes. Compared with the solution of microlens arrays in related technologies where the microlens units have a uniform structure, this application provides a solution for forming microlens arrays with different patterns. Furthermore, microlens structures of different shapes have different optical effects. Microlens units with different optical effects can produce different optical effects on pixel units. This can both enable pixel units with the same optical performance to produce different optical effects, thus enriching the display effect of the micro-light-emitting diode chip, and adjust the optical effects of pixel units with different optical performances so that pixel units with different optical performances ultimately produce the same display effect, thereby improving the display consistency of the micro-light-emitting diode chip. Based on this, the micro-light-emitting diode chip of this application has richer display performance under the action of the microlens array, and the display of the light-emitting structure of this application is more flexible. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of this application. Those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0031] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0032] Figure 1 A schematic diagram of a light-emitting structure provided in an embodiment of this application;

[0033] Figure 2 This is a schematic diagram of the structure of the microlens array provided in the embodiments of this application;

[0034] Figure 3 This is a schematic diagram of the structure of the miniature light-emitting diode chip provided in the embodiments of this application;

[0035] Figure 4 A schematic diagram showing the connection between the miniature light-emitting diode chip and the driver chip provided in an embodiment of this application;

[0036] Figure 5 A schematic flowchart of a method for preparing a light-emitting structure provided in an embodiment of this application;

[0037] Figure 6 A schematic diagram illustrating the formation of a hydrophobic layer and a hydrophilic region in an embodiment of this application;

[0038] Figure 7 A schematic diagram illustrating the formation of a first microlens unit and a second microlens unit using a microlens array provided in an embodiment of this application;

[0039] Figure 8 This is another schematic flowchart illustrating the method for preparing the light-emitting structure provided in the embodiments of this application;

[0040] Figure 9 This is a schematic diagram of a display device provided in an embodiment of this application.

[0041] The reference numerals in the attached figures are as follows:

[0042] 10. Light-emitting structure; 20. Display device; 100. Micro-LED chip; 200. Microlens array; 300. Color conversion layer; 400. Hydrophobic layer; 500. Driver chip; 110. First pixel unit; 120. Second pixel unit; 111. First sub-pixel unit; 112. Second sub-pixel unit; 210. First microlens unit; 220. Second microlens unit; 230. Cylindrical photoresist pillar; 310. Color conversion area; 320. Light-transmitting area; 330. Black matrix structure; 311. Red quantum dot structure; 312. Green quantum dot structure; 41 0. Hydrophobic region; 420. Hydrophilic region; 430. Hydrophobic structure; 440. Photoresist layer; 450. Opening region; 101. First substrate; 102. Buffer layer; 103. First semiconductor layer; 104. Light-emitting layer; 105. Second semiconductor layer; 106. Current diffusion layer; 107. First electrode layer; 108. Second electrode layer; 109. Solder joint structure; 501. Second substrate; 502. Driving circuit; 503. Driving pad; H1. First direction; H2. Second direction; L1. First dimension; L2. Second dimension; L3. Third dimension; L4. Fourth dimension. Detailed Implementation

[0043] The following will refer to the appendices in this application. Figure 1 To be continued Figure 9 The technical solutions in this application are clearly and completely described in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0044] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0045] In near-eye display technology, Micro-LED display modules are considered a very promising technology due to their excellent optical performance, compact size, and low power consumption. Quantum dot color conversion structures offer advantages such as easy integration, high color gamut, and high efficiency, making them a crucial technological route for achieving high-resolution full-color Micro-LEDs. Full-color display is achieved by exciting red and green quantum dots with blue Micro-LED pixels. However, the light-emitting characteristics of red and green quantum dots differ from those of Micro-LED blue pixels, leading to color shift at wide viewing angles. Specifically, while Micro-LED blue pixels have wide viewing angles, the filter layer and black matrix layer integrated on top of them cause absorption of blue light at wide viewing angles, resulting in a low proportion of blue light pixels at wide viewing angles in the Micro-LED display module. Quantum dots, on the other hand, have wide viewing angles, so the proportion of red and green sub-pixels is higher at wide viewing angles compared to normal viewing angles, causing a yellowish tint and image quality degradation in full-color Micro-LEDs at wide viewing angles.

[0046] To address the aforementioned issues, a common solution in related technologies is to fill the blue sub-pixels with nanoscale scattering particles to improve the viewing angle of blue Micro-LEDs. However, in applications such as near-eye displays, to improve the coupling efficiency of the Micro-LED light engine, the emitted light beam needs to be collimated. This requires collimation through optical design and other methods. Therefore, the nanoscale scattering particle filling solution is not suitable for near-eye display devices. Another common method in related technologies is to control the emitted light beam of Micro-LED pixels using microlens structures. To obtain red, green, and blue sub-pixels with consistent emission characteristics after collimation, the microlens structure needs to be adapted to the original emission characteristics of the Micro-LED pixels. For example, the microlens structure corresponding to the red and green pixels may differ from the microlens structure corresponding to the blue pixels in height, curvature, or material properties. Microlens manufacturing methods include photolithography, thermal reflow, inkjet printing, and imprinting. These methods typically produce microlenses with uniform materials and structures, making patterning difficult and hindering the differentiation between the microlens structure corresponding to the red and green pixels and the microlens structure corresponding to the blue pixels.

[0047] To address the aforementioned technical problems, this application provides a microlens patterning scheme that distinguishes the microlens structure corresponding to red and green pixels from that corresponding to blue pixels, thereby solving the color shift problem in quantum dot color conversion Micro-LED display modules. The solution of this application is described in detail below.

[0048] Please refer to Figure 1 , Figure 1This is a schematic diagram of a light-emitting structure 10 provided in an embodiment of this application. The light-emitting structure 10 includes a micro light-emitting diode chip 100, a microlens array 200, and a hydrophobic layer 400.

[0049] The micro-LED chip 100 includes multiple pixel units, each pixel unit emitting light of the same color or different colors. A hydrophobic layer 400 is disposed on the light-emitting side of the micro-LED chip 100, and the hydrophobic layer 400 includes a hydrophobic region 410 and a hydrophilic region 420, both of which cover at least one pixel unit. The microlens array 200 includes multiple microlens units, each corresponding to one pixel unit. Light emitted from each pixel is emitted to the outside of the light-emitting structure 10 via the corresponding microlens unit.

[0050] It is understood that both the hydrophobic layer 400 and the microlens array 200 are light-transmitting structures. The microlens array 200, the hydrophobic layer 400, and the micro-LED chip 100 are stacked along a first direction H1, which is the thickness or height direction of the light-emitting structure 10. Multiple pixel units on the micro-LED chip 100 are spaced apart along a second direction H2, which can be the length or width direction of the light-emitting structure 10. At this time, the multiple microlens units of the microlens array 200 are also spaced apart along the second direction H2.

[0051] It is understood that the micro-LED chip 100 includes a plurality of first pixel units 110 and a plurality of second pixel units 120. Correspondingly, the microlens array 200 includes a plurality of first microlens units 210 and a plurality of second microlens units 220. The plurality of first microlens units 210 are configured in a one-to-one correspondence with the plurality of first pixel units 110, such that at least a portion of the projection of each first microlens unit 210 along the first direction H1 overlaps with the corresponding first pixel unit 110. The plurality of second microlens units 220 are configured in a one-to-one correspondence with the plurality of second pixel units 120, such that at least a portion of the projection of each second microlens unit 220 along the first direction H1 overlaps with the corresponding second pixel unit 120.

[0052] It is understood that the hydrophobic region 410 and the hydrophilic region 420 on the hydrophobic layer 400 are disposed on the same layer, adjacent to each other and connected. The hydrophobic region 410 can cover all the first pixel units 110, and the hydrophilic region 420 can cover all the second pixel units 120. Among them, the pixel unit corresponding to the hydrophobic region 410 is the first pixel unit 110, and the microlens unit corresponding to the hydrophobic region 410 is the first microlens unit 210. The pixel unit corresponding to the hydrophilic region 420 is the second pixel unit 120, and the microlens unit corresponding to the hydrophilic region 420 is the second microlens unit 220.

[0053] Understandably, the hydrophilic region 420 refers to the area in a molecule that can easily dissolve in water by forming hydrogen bonds or through other interactions with water molecules. These regions typically contain polar groups, such as -OH (hydroxyl), -COOH (carboxyl), and -NH2 (amino). The hydrophilic region 420 gives the molecule good water solubility, and through interactions such as hydrogen bonds, it can tightly bind with other molecules or water molecules containing the hydrophilic region 420. Conversely, the hydrophobic region 410 refers to the area in a molecule that does not easily interact with water and tends to avoid it. These regions are typically nonpolar groups, such as hydrocarbon groups (e.g., -CH3, -C6H5). The hydrophobic region 410 reduces the molecule's solubility in water. Molecules with the hydrophobic region 410 tend to aggregate in water to reduce their contact area with water.

[0054] It is understandable that when the first microlens unit 210 and the second microlens unit 220 are formed on the hydrophobic layer 400, and the first microlens unit 210 is formed in the hydrophobic region 410 and the second microlens unit 220 is formed in the hydrophilic region 420, the hydrophobic region 410 causes the molecular structure of the first microlens unit 210 to aggregate together, thereby reducing the contact area with the hydrophobic region 410. The first microlens unit 210 can form a structure with a small contact area with the hydrophobic region 410. Conversely, the hydrophilic region 420 causes the molecular structure of the second microlens unit 220 to be tightly packed with the hydrophilic region 420, increasing the contact area with the hydrophilic region 420. The second microlens unit 220 can form a structure with a large contact area with the hydrophilic region 420. Therefore, under the influence of the hydrophilic region 420 and the hydrophobic region 410, the first microlens unit 210 and the second microlens unit 220 of this application can form microlens structures with different shapes.

[0055] In the light-emitting structure 10 of this application embodiment, a plurality of microlens units of the microlens array 200 are formed on the side of the hydrophobic layer 400 facing away from the micro-light-emitting diode chip 100. Since the hydrophobic layer 400 includes a hydrophobic region 410 and a hydrophilic region 420, the microlens units formed in the hydrophobic region 410 and the microlens units formed in the hydrophilic region 420 can form microlens structures with different shapes. Compared with the solution of the microlens array 200 of the related art where the microlens units have a uniform structure, this application provides a solution for the microlens array 200 to form different patterns. Furthermore, microlens structures of different shapes possess different optical effects. The first microlens unit 210 and the second microlens unit 220, with their different optical effects, can produce different optical effects on the first pixel unit 110 and the second pixel unit 120. This not only allows pixel units with the same optical performance to produce different optical effects, enriching the display effect of the micro-LED chip 100, but also allows the optical effects of pixel units with different optical performances to be adjusted so that they ultimately produce the same display effect, thus improving the display consistency of the micro-LED chip 100. Based on this, the micro-LED chip 100 of this application possesses richer display performance under the action of the microlens array 200.

[0056] Please continue to refer to the following: Figure 1 The light-emitting structure 10 in this embodiment further includes a color conversion layer 300. The color conversion layer 300 is disposed along the first direction H1 between the micro light-emitting diode chip 100 and the hydrophobic layer 400. The color conversion layer 300 includes a color conversion region 310 and a light-transmitting region 320. The hydrophobic region 410 covers the color conversion region 310, and the hydrophilic region 420 covers the light-transmitting region 320. The color conversion region 310 is used to convert the light emission color of the pixel unit it covers, and the light-transmitting region 320 is used to transmit the light emission of the pixel unit it covers.

[0057] Understandably, at least a portion of the projection of the color conversion region 310 along the first direction H1 overlaps with the first pixel unit 110. The color conversion region 310 is configured corresponding to the first pixel unit 110 and is used to convert the emitted color of the first pixel unit 110. At least a portion of the projection of the light-transmitting region 320 along the first direction H1 overlaps with the second pixel unit 120. The light-transmitting region 320 is configured corresponding to the second pixel unit 120 and is used to transmit the emitted light of the second pixel unit 120. The color conversion region 310 may contain, but is not limited to, color conversion structures such as quantum dot structures, phosphorescent structures, fluorescent structures, and thermochromic structures to convert the emitted color of the pixel unit. Quantum dot structures are a type of nanoconductor material with unique photoelectric properties; when excited by external energy (such as light or electricity), they emit light of a specific frequency. The light-transmitting region 320 does not contain color conversion structures such as quantum dot structures; the light-transmitting region 320 allows light to maintain its original color and pass through.

[0058] Understandably, in some examples, the first pixel unit 110 and the second pixel unit 120 of the micro LED chip 100 emit light of the same color. Under the action of the color conversion layer 300, the light emitted by the first pixel unit 110 is converted into light of a different color by the color conversion structure, such as a quantum dot structure, within the color conversion region 310, while the light emitted by the second pixel unit 120 directly passes through the light-transmitting region 320 and retains its original color. Thus, under the action of the color conversion layer 300, the first pixel unit 110 and the second pixel unit 120 can emit light of different colors, and the light-emitting structure 10 of this application can achieve color display. Of course, in other examples, the first pixel unit 110 and the second pixel unit 120 can also emit light of different colors and achieve monochrome or color display under the action of the color conversion layer 300.

[0059] It is understandable that, such as Figure 1 As shown, the color conversion layer 300 also includes a black matrix structure 330, which is disposed between adjacent color conversion structures such as quantum dot structures and between the color conversion structures such as quantum dot structures and the light-transmitting area 320. The black matrix structure 330 can prevent light passing through the quantum dot structure and the light-transmitting area 320 from interfering with each other and can absorb stray light.

[0060] Understandably, the light-emitting characteristics of color conversion structures, such as quantum dot structures, differ from those of the pixel units of the micro-LED chip 100. For example, the pixel units of the micro-LED chip 100 have wide viewing angle light emission characteristics, but due to the influence of structures such as the filter layer and color conversion layer 300 integrated above the micro-LED chip 100, the light from the pixel units at a wide viewing angle is absorbed. In contrast, color conversion structures, such as quantum dot structures, have wide viewing angle light emission characteristics, and the proportion of light emitted by the quantum dot structure at a wide viewing angle is relatively higher than at a normal viewing angle. Therefore, after the light emitted by the micro-LED chip 100 passes through the color conversion layer 300, the wide viewing angle ratio of the light in the region corresponding to the first pixel unit 110 is higher than that of the light in the region corresponding to the second pixel unit 120, resulting in a color shift problem in the light-emitting structure 10.

[0061] In the light-emitting structure 10 of this application embodiment, under the action of the hydrophobic region 410 and the hydrophilic region 420 of the hydrophobic layer 400, the first microlens unit 210 and the second microlens unit 220 form two microlens structures with different shapes and different optical properties. The two microlens structures can adaptively adjust the ratio of the light emitted by the first pixel unit 110 and the second pixel unit 120 under the wide viewing angle and the normal viewing angle, thereby solving the color shift problem of the light-emitting structure 10 and making the light-emitting structure 10 have better display consistency performance.

[0062] In some examples, multiple pixel units of the micro LED chip 100 are used to emit light of a first color. The color conversion region 310 is provided with a first quantum dot structure and a second quantum dot structure. The first quantum dot structure is used to convert the pixel units it covers into light of a second color, and the second quantum dot structure is used to convert the pixel units it covers into light of a third color. The first color, the second color, and the third color are all different, so that the light-emitting structure 10 of this embodiment can realize color display.

[0063] For example, the first pixel unit 110 and the second pixel unit 120 of the micro LED chip 100 are both used to emit blue light. The first pixel unit 110 includes a first sub-pixel unit 111 and a second sub-pixel unit 112. The color conversion region 310 is provided with a red quantum dot structure 311 and a green quantum dot structure 312. The red quantum dot structure 311 is set corresponding to the first sub-pixel unit 111, and the red quantum dot structure 311 can convert the blue light emitted by the first sub-pixel unit 111 into red light after passing through the red quantum dot structure 311. The green quantum dot structure 312 is set corresponding to the second sub-pixel unit 112. The green quantum dot structure 312 can convert the blue light emitted by the second sub-pixel unit 112 into green light after passing through the green quantum dot structure 312. Thus, under the action of the color conversion layer 300, the light-emitting structure 10 can generate red, green, and blue light to achieve full-color display.

[0064] It is understandable that red and green light are generated by the quantum dot structure within the color conversion region 310, and their emission characteristics differ from the blue light emitted by the second pixel unit 120. The blue light generated by the second pixel unit 120 has a wide viewing angle emission characteristic, which is absorbed by the upper filter and black matrix. The quantum dot structure has a wide viewing angle emission characteristic, and the proportion of red and green light is higher at a wide viewing angle than at a normal viewing angle, resulting in a yellowish color deviation in the full-color display of the light-emitting structure 10 at wide viewing angles. However, the microlens array 200 of this application is adapted to the emission characteristics of the first pixel unit 110 and the second pixel unit 120, so that the first microlens structure corresponding to the first pixel unit 110 has different characteristics in height, curvature, etc. than the second microlens structure corresponding to the second pixel unit 120, thereby solving the color shift problem of the light-emitting structure 10 and giving the light-emitting structure 10 better display consistency performance.

[0065] In this regard, please combine Figure 1 Please refer to Figure 2 , Figure 2This is a schematic diagram of the structure of the microlens array 200 provided in an embodiment of this application. In some examples, the height of the second microlens unit 220 is less than the height of the first microlens unit 210, and the width of the second microlens unit 220 is greater than or equal to the width of the first microlens unit 210. Alternatively, the first dimension L1 of the second microlens unit 220 along the first direction H1 is less than the second dimension L2 of the first microlens unit 210 along the first direction H1, and the third dimension L3 of the second microlens unit 220 along the second direction H2 is greater than or equal to the fourth dimension L4 of the first microlens unit 210 along the second direction H2. These first dimensions L1 to fourth dimensions L4 are all the maximum dimensions in their respective directions.

[0066] It is understandable that, in the second direction H2, the distance between two adjacent first microlens units 210 is greater than the distance between two adjacent second microlens units 220, and also greater than the distance between adjacent first microlens units 210 and second microlens units 220.

[0067] Understandably, compared to the first microlens unit 210, the second microlens unit 220 is shorter and wider, exhibiting a "short and wide" shape, while the first microlens unit 210 is "tall and narrow." The "short and wide" shape of the second microlens unit 220 allows for a larger light-gathering angle, enabling it to accept a wider range of incident light and effectively collect light from different directions, resulting in a larger field of view. The "tall and narrow" shape of the first microlens unit 210 has a stronger light-gathering ability, allowing light to converge at a smaller angle, thus achieving precise light focusing.

[0068] In this embodiment, when the light emitted from the second pixel unit 120 passes through the light-transmitting area 320 and then through the second microlens unit 220, the "short and wide" shape of the second microlens unit 220 increases the convergence angle of the light, thus increasing the proportion of light, such as blue light, passing through the second microlens unit 220 at a wide viewing angle. However, when the light emitted from the first pixel unit 110 passes through the color conversion area 310 and then through the first microlens unit 210, the "tall and narrow" shape of the first microlens unit 210 has a relatively smaller convergence angle than the second microlens unit 220, resulting in a decrease in the proportion of light, such as red and green light, passing through the first microlens unit 210 at a wide viewing angle. Therefore, the proportion of light emitted by the first pixel unit 110 (e.g., red and green light), which originally had a larger proportion at a wide viewing angle, decreases after passing through the first microlens unit 210; while the proportion of light emitted by the second pixel unit 120 (e.g., blue light), which originally had a smaller proportion at a wide viewing angle, increases after passing through the second microlens unit 220. Furthermore, the full-color light converted by the color conversion layer 300 can achieve a relatively uniform proportion of full-color light under the action of the microlens array 200 at a wide viewing angle. The solution of this application can solve the color deviation problem of quantum dot color conversion full-color Micro-LED. The light-emitting structure 10 of this application has better display consistency performance.

[0069] In this regard, please combine Figure 1 and Figure 2 In some examples, the radius of curvature of the first microlens unit 210 is less than or equal to the radius of curvature of the second microlens unit 220. Since a smaller curvature and a larger radius of curvature result in a more gradual shape for the microlens structure, the surface curvature of the microlens structure is reduced, and the bulge of the central portion relative to the edge portion of the microlens structure is decreased. Furthermore, the height of the second microlens unit 220 with a larger radius of curvature is less than the height of the first microlens unit 210 with a smaller radius of curvature, and the width of the second microlens unit 220 with a larger radius of curvature can be greater than or equal to the width of the first microlens unit 210 with a smaller radius of curvature. The second microlens unit 220 has a "short and wide" shape, while the first microlens unit 210 has a "tall and narrow" shape. At this time, under the action of the microlens array 200, the light-emitting structure 10 of this application embodiment can make the full-color light converted by the color conversion layer 300 achieve a relatively uniform proportion of full-color light under the action of the microlens array 200 at a large viewing angle. The solution of this application can solve the color deviation problem of quantum dot color conversion full-color Micro-LED, and the light-emitting structure 10 has better display consistency performance.

[0070] In some examples, the first microlens unit 210 and the second microlens unit 220 are formed on the hydrophobic layer 400 using the same process. For example, the first microlens unit 210 is formed in the hydrophobic region 410 using photolithography and thermal reflow processes, and the second microlens unit 220 is formed in the hydrophilic region 420 using the same photolithography and thermal reflow processes. The photolithography process forms the microlens array 200 by combining the photochemical reaction of photoresist and development processes with mask pattern transfer. For example, photoresist is first spin-coated onto a substrate, such as the hydrophobic layer 400, and then exposed to ultraviolet light through a mask, followed by development to form the microlens array 200. The thermal reflow process utilizes the surface tension self-forming properties of thermoplastic materials (such as photoresist and polymers) when heated and melted to form a smooth lens surface. For example, heating a substrate, such as a hydrophobic layer 400, melts the photoresist on it, forming a hemispherical lens under surface tension. Finally, the lens is cured by ultraviolet light or used as a mold to replicate other materials (such as PDMS), achieving a lens size of submicron (<1μm).

[0071] It is understood that, in this embodiment, since the first microlens unit 210 is formed in the hydrophobic region 410 and the second microlens unit 220 is formed in the hydrophilic region 420, during the thermal reflow process, the photoresist corresponding to the second microlens unit has a larger contact area with the hydrophilic region 420 due to surface tension and the hydrophilic properties of the hydrophilic region 420, thus forming a "short and wide" shape. The photoresist corresponding to the first microlens unit 210 has a relatively smaller contact area with the hydrophobic region 410 due to surface tension and the hydrophobic properties of the hydrophobic region 410, thus forming a "tall and narrow" shape. Therefore, under the influence of the hydrophobic region 410 and the hydrophilic region 420 of the hydrophobic layer 400, the first microlens unit 210 and the second microlens unit 220 in this embodiment can form microlens structures of different shapes through photolithography and thermal reflow processes, thereby realizing the patterned design of the microlens array 200.

[0072] In some examples, the hydrophobic layer 400 is used to form the hydrophobic region 410 and the hydrophilic region 420 through a hydrophobic structure deposition process, a photolithography process, and an oxygen plasma local modification process. For example, a hydrophobic layer 400 (e.g., fluorosilane) is deposited on the side of the color conversion layer 300 opposite to the micro LED chip 100, and then the hydrophilic region 420 is formed by an oxygen plasma local modification process on the upper opening of the second pixel unit 120 through a photolithography process, followed by the removal of other photoresist to form the hydrophobic region 410.

[0073] In this embodiment, the first microlens unit 210 and the second microlens unit 220 are formed by photolithography and thermal reflow processes. Compared with other processes for forming microlens structures, photolithography and thermal reflow processes are compatible with a variety of substrate materials, such as silicon wafers, glass, and polymers, enabling the microlens array 200 to be integrated into different optical devices. At the same time, photolithography and thermal reflow processes are relatively simple, do not require complex equipment and masks, have low production costs, and are suitable for large-scale production.

[0074] Please refer to the following: Figure 3 , Figure 3 This is a schematic diagram of the structure of a micro LED chip 100 provided in an embodiment of this application. The micro LED chip 100 in this embodiment includes a first substrate 101, and a buffer layer 102, a first semiconductor layer 103, a light-emitting layer 104, a second semiconductor layer 105, a current diffusion layer 106, a first electrode layer 107, a second electrode layer 108, and a solder joint structure 109 formed on the first substrate 101. The first semiconductor layer 103, the light-emitting layer 104, the second semiconductor layer 105, the current diffusion layer 106, the first electrode layer 107, and the solder joint structure 109 connected thereto can form multiple spaced pixel structures. Each pixel structure includes a first pixel unit 110 and a second pixel unit 120. A color conversion layer 300 and a microlens array 200 are disposed on the light-emitting side of the pixel structure.

[0075] Please refer to the following: Figure 4 , Figure 4 This is a schematic diagram showing the connection between the micro LED chip 100 and the driver chip 500 provided in an embodiment of this application. The light-emitting structure 10 may further include the driver chip 500. The driver chip 500 includes a second substrate 501, a driving circuit 502 formed on the second substrate 501, and one or more driving pads 503. The one or more driving pads 503 are configured and bonded one-to-one with one or more solder joint structures 109 of the micro LED chip 100. The driver chip 500 and the micro LED chip 100 are bonded together to form an integral unit. In this integral unit, the first substrate 101 of the micro LED chip 100 can be peeled off. The color conversion layer 300 and the microlens array 200 are disposed on the light-emitting side of the integral unit, for example, on the side of the buffer layer 102 of the micro LED chip 100 facing away from the driver chip 500.

[0076] In addition to the above-mentioned light-emitting structure 10, this application embodiment also provides a method for preparing the light-emitting structure 10, please refer to... Figure 5 , Figure 5 This is a schematic flowchart of a method for preparing the light-emitting structure 10 provided in an embodiment of this application. The preparation method includes:

[0077] In S11, a hydrophobic layer 400 is formed on the light-emitting side of the micro LED chip 100. The hydrophobic layer 400 includes a hydrophobic region 410 and a hydrophilic region 420. The micro LED chip 100 includes multiple pixel units, and both the hydrophobic region 410 and the hydrophilic region 420 cover at least one pixel unit.

[0078] The hydrophobic layer 400 is a transparent structure, allowing light generated by the pixel units of the micro-LED chip 100 to propagate outwards through it. The hydrophobic layer 400 can be formed with hydrophobic regions 410 and hydrophilic regions 420 through processes such as hydrophobic deposition, photolithography, and oxygen plasma local modification. The micro-LED chip 100 includes a first pixel unit 110 corresponding to the hydrophobic region 410 and a second pixel unit 120 corresponding to the hydrophilic region 420. The hydrophobic region 410 covers all the first pixel units 110, and the hydrophilic region 420 covers all the second pixel units 120.

[0079] In S12, multiple microlens units are formed on the side of the hydrophobic layer 400 facing away from the micro LED chip 100, and the multiple microlens units are arranged in a one-to-one correspondence with multiple pixel units to form a light-emitting structure 10.

[0080] This step involves forming a first microlens unit 210 corresponding to the first pixel unit 110 in the hydrophobic region 410 and a second microlens unit 220 corresponding to the second pixel unit 120 in the hydrophilic region 420, thus forming a light-emitting structure 10. The first microlens unit 210 and the second microlens unit 220 are formed on the hydrophobic layer 400 using the same process. This same process refers to the same process flow and process conditions.

[0081] It is understood that the first microlens unit 210 and the second microlens unit 220 can be formed, but are not limited to, using the same photolithography and thermal reflow processes. Since the first microlens unit 210 is formed in the hydrophobic region 410 and the second microlens unit 220 is formed in the hydrophilic region 420, the shapes of the first microlens unit 210 and the second microlens unit 220 are different. The two microlens units with different shapes have different optical properties. The two microlens units can adaptively adjust the ratio of the emitted light from the first pixel unit 110 and the second pixel unit 120 at both wide and normal viewing angles, thereby solving the color shift problem of the light-emitting structure 10 and giving the light-emitting structure 10 superior display consistency performance.

[0082] In some examples, please refer to Figure 6 , Figure 6This is a schematic diagram illustrating the formation of a hydrophobic layer 400 with a hydrophilic region 420 and a hydrophobic region 410, as provided in an embodiment of this application. A hydrophobic layer 400 is formed on the light-emitting side of a micro-light-emitting diode chip 100. The hydrophobic layer 400 includes a hydrophobic region 410 and a hydrophilic region 420, comprising: as... Figure 6 As shown, a hydrophobic structure 430 and a hydrophobic layer 400 are formed on the light-emitting side of the micro-LED chip 100. The hydrophobic structure 430 may include, but is not limited to, fluorosilane, polydimethylsiloxane, and methyl methacrylate. A photoresist layer 440 is formed on the side of the hydrophobic layer 400 facing away from the micro-LED chip 100. An opening region 450 communicating with the hydrophobic layer 400 is formed in the region of the photoresist layer 440 corresponding to at least one pixel unit (e.g., the region corresponding to the second pixel unit 120). An oxygen plasma local modification process is performed on the opening region 450, and a hydrophilic region 420 is formed on the hydrophobic layer 400. The photoresist layer 440 in other regions is removed, and a hydrophobic region 410 is formed on the hydrophobic layer 400.

[0083] This application provides a scheme to achieve patterning of the microlens array 200 by depositing a hydrophobic layer 400 on a quantum dot color conversion full-color Micro-LED structure and then performing oxygen plasma local modification on the opening corresponding to the blue sub-pixel through photolithography.

[0084] In some examples, an oxygen plasma localization process is performed in the opening region 450 to form a hydrophilic region 420 on the hydrophobic layer 400. This includes performing a reactive ion etching (RIE) or inductively coupled plasma (ICP) process in the opening region 450 to form the hydrophilic region 420 on the hydrophobic layer 400. It is understood that the RIE or ICP process can be performed at low power (50 watts to 200 watts) to form the hydrophilic region 420. Subsequently, excess photoresist layer 440 is removed using a developer to form the hydrophobic region 410.

[0085] In this embodiment, oxygen plasma is used to locally modify the opening region 450 using either RIE or ICP processes. Compared to other processes, RIE allows for precise control of the etching of the opening region 450. ICP processes can generate high-density plasma, thereby achieving a higher etching rate; meanwhile, ICP processes can maintain good etching uniformity and can be performed at lower temperatures.

[0086] It should be noted that, in addition to forming the hydrophilic region 420 through oxygen plasma local modification in the opening region 450, the embodiments of this application can also form the hydrophilic region 420 and the hydrophobic region 410 through methods such as photolithography, microcontact printing, chemical oxidation and reduction processes, and sol-gel processes. Photolithography can use two different photoresists, one for forming the hydrophilic region 420 and the other for forming the hydrophobic region 410. Microcontact printing utilizes an elastic stamp with a specific pattern to transfer functional molecules to the substrate surface. The functional molecules react chemically with the substrate to form a self-assembled monolayer, and depending on the chemical properties of the functional molecules, the hydrophilic region 420 and the hydrophobic region 410 can be formed on the substrate. Chemical oxidation and reduction processes introduce hydrophilic functional groups to the substrate surface through chemical oxidation reactions to form the hydrophilic region 420, and through chemical reduction reactions or reactions with hydrophobic reagents, introduce hydrophobic groups to the substrate surface to form the hydrophobic region 410. The sol-gel process coats a precursor solution containing hydrophilic groups onto the substrate surface to form a hydrophilic region 420; or, hydrophobic additives are added or a hydrophobic precursor is used to make the prepared film hydrophobic and form a hydrophobic region 410.

[0087] In some examples, multiple microlens units are formed on the side of the hydrophobic layer 400 facing away from the micro LED chip 100, including: performing photolithography and thermal reflow processes on the side of the hydrophobic layer 400 facing away from the micro LED chip 100 to form multiple microlens units.

[0088] This step involves performing photolithography and thermal reflow processes on the hydrophobic layer 400, forming a first microlens unit 210 corresponding to the first pixel unit 110 in the hydrophobic region 410, and forming a second microlens unit 220 corresponding to the second pixel unit 120 in the hydrophilic region 420.

[0089] It is understandable that, such as Figure 7 As shown, Figure 7This is a schematic diagram illustrating the formation of a first microlens unit 210 and a second microlens unit 220 in the microlens array 200 provided in this embodiment. The photolithography process on the hydrophobic layer 400 includes spin-coating photoresist (such as SU-8 or AZ series photoresist) onto the substrate, followed by exposure to ultraviolet light through a mask, and development to form cylindrical photoresist pillars 230. Subsequently, in a thermal reflow process, the cylindrical photoresist pillars 230 are heated above the glass transition temperature of the photoresist, causing them to soften and begin to flow. Due to surface tension, the cylindrical structure may gradually transform into a hemispherical or near-spherical shape, thus forming a microlens structure. Due to the hydrophilic region 420 and the hydrophobic region 410, the cylindrical photoresist pillars 230 formed in the hydrophobic region 410 will form a "tall and narrow" first microlens unit 210, while the cylindrical photoresist pillars 230 formed in the hydrophilic region 420 will form a "short and wide" second microlens unit 220.

[0090] In this embodiment, the first microlens unit 210 and the second microlens unit 220 are formed by photolithography and thermal reflow processes. Compared with other processes for forming microlens structures, photolithography and thermal reflow processes are compatible with a variety of substrate materials, such as silicon wafers, glass, and polymers, enabling the microlens array 200 to be integrated into different optical devices. At the same time, photolithography and thermal reflow processes are relatively simple, do not require complex equipment and masks, have low production costs, and are suitable for large-scale production.

[0091] It should be noted that, in addition to forming microlens units through photolithography and thermal reflow processes, the embodiments of this application can also form microlens units through, but are not limited to, inkjet printing and laser direct writing processes. Inkjet printing is an additive manufacturing technology that can directly form microlenses on a substrate. By controlling the droplet volume and the curing process, a microlens array 200 with a high numerical aperture can be fabricated. Laser direct writing technology fabricates the microlens array 200 by adjusting the laser pulse energy, offering high precision and flexibility.

[0092] In some examples, a hydrophobic layer 400 is formed on the light-emitting side of the micro-LED chip 100, including forming the hydrophobic layer 400 on the side of the color conversion layer 300 facing away from the micro-LED chip 100. The color conversion layer 300 includes a color conversion region 310 and a light-transmitting region 320. The color conversion region 310 is disposed corresponding to the first pixel unit 110 and is used to convert the emitted color of the first pixel unit 110. The light-transmitting region 320 is disposed corresponding to the second pixel unit 120 and is used to transmit the emitted color of the second pixel unit 120.

[0093] In this embodiment, the hydrophobic layer 400 is formed on the side of the color conversion layer 300 facing away from the micro light-emitting diode chip 100. The first microlens unit 210 and the second microlens unit 220 formed on the hydrophobic layer 400 can solve the color shift problem of the light-emitting structure 10 caused by the color conversion layer 300, and the light-emitting structure 10 has better display consistency performance.

[0094] Based on the above explanation, please refer to Figure 8 , Figure 8 This is another schematic flowchart illustrating the preparation method of the light-emitting structure 10 provided in the embodiments of this application. The preparation method includes:

[0095] In S21, a hydrophobic structure 430 and a hydrophobic layer 400 are formed on the side of the color conversion layer 300 facing away from the micro light-emitting diode chip 100.

[0096] The miniature light-emitting diode chip 100 includes a first pixel unit 110 and a second pixel unit 120. The color conversion layer 300 includes a color conversion region 310 and a light-transmitting region 320. The color conversion region 310 is disposed corresponding to the first pixel unit 110 and is used to convert the emitted color of the first pixel unit 110. The light-transmitting region 320 is disposed corresponding to the second pixel unit 120 and is used to transmit the emitted light from the second pixel unit 120. The hydrophobic structure 430 may include, but is not limited to, fluorosilane. Figure 6 As shown, the hydrophobic structure 430 covers the entire color conversion layer 300 away from the surface of the micro LED chip 100 and forms a hydrophobic layer 400.

[0097] In S22, a photoresist layer 440 is formed on the side of the hydrophobic layer 400 facing away from the micro LED chip 100.

[0098] In S23, an opening region 450 communicating with the hydrophobic layer 400 is formed in the region of the photoresist layer 440 corresponding to the second pixel unit 120.

[0099] like Figure 6 As shown, a photoresist layer 440 is deposited on and covers the entire hydrophobic layer 400. Subsequently, the photoresist corresponding to the second pixel unit 120 is removed by an etching process, and the photoresist layer 440 forms an opening region 450. The opening region 450 is connected to the hydrophobic layer 400, and the photoresist above the hydrophobic layer 400 corresponding to the opening region 450 is removed.

[0100] In S24, oxygen plasma local modification process is performed in the opening region 450, and a hydrophilic region 420 is formed on the hydrophobic layer 400.

[0101] In S25, the photoresist layer 440 in other areas is removed, and a hydrophobic region 410 is formed on the hydrophobic layer 400.

[0102] like Figure 6 As shown, in this step, reactive ion etching (RIE) or inductively coupled plasma (ICP) is performed in the opening region 450, and a hydrophilic region 420 is formed on the hydrophobic layer 400. Subsequently, the excess photoresist layer 440 is removed by developing solution, and a hydrophobic region 410 is formed.

[0103] In S26, a photolithography step and a thermal reflow step are performed on the hydrophobic layer 400, and a first microlens unit 210 corresponding to the first pixel unit 110 is formed in the hydrophobic region 410, and a second microlens unit 220 corresponding to the second pixel unit 120 is formed in the hydrophilic region 420.

[0104] like Figure 7 As shown, this step involves photolithography on the hydrophobic layer 400, including spin-coating photoresist onto the substrate, exposing it with ultraviolet light through a mask, and developing it to form cylindrical photoresist pillars 230. Subsequently, in a thermal reflow process, the cylindrical photoresist pillars 230 are heated above the glass transition temperature of the photoresist, causing them to soften and begin to flow. Due to surface tension, the cylindrical structure may gradually transform into a hemispherical or near-spherical shape, forming a microlens structure. Since the hydrophobic layer 400 includes a hydrophilic region 420 and a hydrophobic region 410, the cylindrical photoresist pillars 230 formed in the hydrophobic region 410 will form a "tall and narrow" first microlens unit 210, and the cylindrical photoresist pillars 230 formed in the hydrophilic region 420 will form a "short and wide" second microlens unit 220.

[0105] This application provides a scheme for patterning a microlens array 200 by depositing a hydrophobic layer 400 on a quantum dot color-conversion full-color Micro-LED structure and then performing oxygen plasma local modification on the opening corresponding to the blue sub-pixel using photolithography. Simultaneously, the first microlens unit 210 and the second microlens unit 220 are formed through photolithography and thermal reflow processes. These processes are relatively simple, requiring no complex equipment or masks, resulting in low production costs and suitability for mass production. Furthermore, the first microlens unit 210 and the second microlens unit 220 formed on the hydrophobic layer 400 can solve the color shift problem of the light-emitting structure 10 caused by the color conversion layer 300, giving the light-emitting structure 10 superior display consistency.

[0106] Based on the above description, this application also provides a micro light-emitting diode device, including the light-emitting structure 10 of any of the above embodiments, or the light-emitting structure 10 prepared by the method of preparing the light-emitting structure of any of the above embodiments.

[0107] Based on the above description, this application also provides a display device 20, please refer to... Figure 9 , Figure 9 This is a schematic diagram of a display device 20 provided in an embodiment of this application. The display device 20 can be applied to electronic devices to implement extended reality (XR) technologies such as augmented reality (AR), virtual reality (VR), and mixed reality (MR). In implementation, the display device 20 can be a projection component of an electronic device, such as a projector or head-up display (HUD). Alternatively, the display device 20 can also be a display component of an electronic device, such as a smartphone, smartwatch, laptop, tablet, dashcam, navigator, head-mounted device, or any device with a display screen. Furthermore, the display device 20 can also be a lighting component of an electronic device, such as a vehicle or streetlight, or any device with lighting components.

[0108] It is understood that the display device 20 of this application embodiment includes the light-emitting structure 10 of any of the above embodiments, or includes the light-emitting structure 10 prepared by the preparation method of the light-emitting structure 10 of any of the above embodiments. Therefore, this application provides a scheme that can realize the patterning of the microlens array 200, which can also solve the color shift problem of the light-emitting structure 10 caused by the color conversion layer 300.

[0109] It should be noted that the light-emitting structure 10, the method for preparing the light-emitting structure 10, the micro light-emitting diode device, and the display device 20 in the embodiments of this application are different subjects under the same inventive concept. Features not described in detail in each embodiment can be referred to in the description of other embodiments.

[0110] It should be noted that the term "multiple" in this application generally refers to two or more. Furthermore, the directional terms used in the embodiments of this application, such as "up," "down," "front," "back," "left," "right," "inner," "outer," and "side," are only for reference to the accompanying drawings. Therefore, the directional terms used are for illustrating and understanding the embodiments of this application, and not for limiting the embodiments of this application. In the various drawings, structurally similar units are represented by the same reference numerals. For clarity, the various parts in the drawings are not drawn to scale. Additionally, some related parts may not be shown in the drawings.

[0111] It should be understood that in the description of this application, terms such as "first" and "second" are used only to distinguish similar objects and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated.

[0112] It is understood that those skilled in the art, guided by the above embodiments, can combine various implementation methods in the above embodiments to obtain technical solutions with multiple implementation methods. The above descriptions are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

[0113] The luminescent structure and its preparation method provided in this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A light-emitting structure, characterized in that, include: A miniature light-emitting diode chip, comprising multiple pixel units; A hydrophobic layer is disposed on the light-emitting side of the micro LED chip. The hydrophobic layer includes a hydrophobic region and a hydrophilic region, and both the hydrophobic region and the hydrophilic region cover at least one pixel unit. The microlens array includes multiple microlens units that are arranged one-to-one with the multiple pixel units, and the multiple microlens units are formed on the side of the hydrophobic layer facing away from the micro light-emitting diode chip.

2. The light-emitting structure according to claim 1, characterized in that, The microlens array includes a first microlens unit corresponding to the hydrophobic region and a second microlens unit corresponding to the hydrophilic region. The height of the second microlens unit is less than the height of the first microlens unit, and the width of the second microlens unit is greater than or equal to the width of the first microlens unit.

3. The light-emitting structure according to claim 1, characterized in that, The microlens array includes a first microlens unit corresponding to the hydrophobic region and a second microlens unit corresponding to the hydrophilic region, wherein the radius of curvature of the first microlens unit is less than or equal to the radius of curvature of the second microlens unit.

4. The light-emitting structure according to any one of claims 1 to 3, characterized in that, The light-emitting structure further includes: A color conversion layer is disposed between the micro LED chip and the hydrophobic layer. The color conversion layer includes a color conversion region and a light-transmitting region. The hydrophobic region covers the color conversion region, and the hydrophilic region covers the light-transmitting region. The color conversion region is used to convert the emission color of the pixel unit it covers, and the light-transmitting region is used to transmit the emission color of the pixel unit it covers.

5. The light-emitting structure according to claim 4, characterized in that, The plurality of pixel units are all used to emit light of a first color. The color conversion region is provided with a first quantum dot structure and a second quantum dot structure. The first quantum dot structure is used to convert the pixel units it covers into light of a second color, and the second quantum dot structure is used to convert the pixel units it covers into light of a third color. The first color, the second color, and the third color are all different.

6. A method for preparing a light-emitting structure, characterized in that, include: A hydrophobic layer is formed on the light-emitting side of a micro LED chip, the hydrophobic layer comprising a hydrophobic region and a hydrophilic region; The micro LED chip includes multiple pixel units, and both the hydrophobic region and the hydrophilic region cover at least one pixel unit. Multiple microlens units are formed on the side of the hydrophobic layer facing away from the micro LED chip, and the multiple microlens units are arranged in a one-to-one correspondence with the multiple pixel units to form a light-emitting structure.

7. The method for preparing the light-emitting structure according to claim 6, characterized in that, A hydrophobic layer is formed on the light-emitting side of the micro-light-emitting diode chip. The hydrophobic layer includes hydrophobic regions and hydrophilic regions, including: A hydrophobic structure and a hydrophobic layer are formed on the light-emitting side of the micro LED chip; A photoresist layer is formed on the side of the hydrophobic structure facing away from the micro LED chip; An opening region communicating with the hydrophobic layer is formed in the region of the photoresist layer corresponding to at least one pixel unit; A localized oxygen plasma modification process is performed in the opening region to form a hydrophilic region on the hydrophobic layer; Remove the photoresist layer from other areas and form a hydrophobic region on the hydrophobic layer.

8. The method for preparing the light-emitting structure according to claim 7, characterized in that, The process of performing localized oxygen plasma modification in the opening region and forming a hydrophilic region on the hydrophobic layer includes: A reactive ion etching process or an inductively coupled plasma process is performed in the opening region to form a hydrophilic region on the hydrophobic layer.

9. The method for preparing the light-emitting structure according to claim 6, characterized in that, The method involves forming multiple microlens units on the side of the hydrophobic layer opposite to the micro-LED chip, including: Photolithography and thermal reflow processes are performed on the side of the hydrophobic layer opposite to the micro LED chip to form multiple microlens units.

10. The method for preparing the light-emitting structure according to any one of claims 6 to 9, characterized in that, The process of forming a hydrophobic layer on the light-emitting side of the micro LED chip includes: A hydrophobic layer is formed on the side of the color conversion layer facing away from the micro LED chip. The color conversion layer includes a color conversion region and a light-transmitting region. The hydrophobic region covers the color conversion region, and the hydrophilic region covers the light-transmitting region. The color conversion region is used to convert the emission color of the pixel unit it covers, and the light-transmitting region is used to transmit the emission of the pixel unit it covers.

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