Micro-LED display device and display panel

Abstract

The invention discloses a Micro-LED display device and a display panel. The Micro-LED display device comprises a substrate, an integrated circuit layer, an LED light-emitting layer and a biconvex lens device. The integrated circuit layer is arranged on one side of the substrate. The LED light-emitting layer is arranged on one side of the integrated circuit layer and electrically connected to the integrated circuit layer. The biconvex lens device is arranged on the side, away from the integrated circuit, of the LED light-emitting layer, the biconvex lens device is used for converting light rays emitted by the LED light-emitting layer into collimated light rays to be emitted out, an optical device does not need to be additionally arranged outside the Micro-LED display device to shape the light rays, and therefore loss of the light rays in the optical device is avoided, and the light emitting efficiency is improved. The light conversion efficiency of the whole optical system is improved, the weight of the module is reduced, and the module is light and thin.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a Micro-LED display device and a display panel. Background Art

[0002] At present, micro-LED (Micro-Light Emitting Diode) display is a micron-pitch LED array formed by miniaturizing traditional LED to achieve ultra-high density pixel resolution. Micro-LED display has the characteristics of self-luminescence, easier and more accurate adjustment of display color, longer luminous life and higher brightness, and is more lightweight and power-saving. Due to its high-density, small-size and ultra-multi-pixel characteristics, Micro-LED display will become the leader of the third-generation display technology with high realism, interactive and personalized display as its main features.

[0003] Virtual reality (VR) and augmented reality (AR) are important areas of Micro-LED application, and Micro-LED is considered to be the most promising candidate for the next generation of augmented / virtual reality display devices. In order to make AR glasses smaller, thinner, and reach the technical level of consumer level, the industry currently tends to use optical waveguide solutions, but the efficiency of optical waveguides is currently low, and optical devices are required to shape and combine the light before entering the optical waveguide structure, so that the light originally emitted in a Lambert body is collimated and emitted in parallel, but the optical device has serious light loss, and the efficiency of beam shaping is usually only about 10-50%, resulting in low light conversion efficiency. Summary of the invention

[0004] Embodiments of the present invention provide a Micro-LED display device and a display panel, which can solve the technical problem of low light conversion efficiency of existing Micro-LED display devices and display panels.

[0005] The present invention provides a Micro-LED display device, comprising:

[0006] substrate;

[0007] An integrated circuit layer is disposed on one side of the substrate;

[0008] an LED light-emitting layer, disposed on a side of the integrated circuit layer away from the substrate and electrically connected to the integrated circuit layer; and

[0009] The double convex lens device is arranged on a side of the LED light emitting layer away from the substrate, and the double convex lens device is used to convert the light emitted by the LED light emitting layer into collimated light for outgoing emission.

[0010] According to the Micro-LED display device provided by the present invention, the LED light-emitting layer includes an epitaxial stacked structure, and the epitaxial stacked structure includes:

[0011] A first epitaxial layer, disposed on one side of the integrated circuit layer, for emitting light of a first color;

[0012] a second epitaxial layer, disposed on a side of the first epitaxial layer away from the substrate and bonded to the first epitaxial layer, the second epitaxial layer being used to emit a second color light; and

[0013] A third epitaxial layer, disposed on a side of the second epitaxial layer away from the substrate and bonded to the second epitaxial layer, the third epitaxial layer being used to emit a third color light;

[0014] The double convex lens device is arranged on a side of the third epitaxial layer away from the substrate, and is used for converting the first color light, the second color light and the third color light into collimated light for emission.

[0015] According to the Micro-LED display device provided by the present invention, the double convex lens device includes a first lens and a second lens, and the distance from the surface of one side of the first lens close to the substrate to the third epitaxial layer is smaller than the distance from the surface of one side of the second lens close to the substrate to the third epitaxial layer;

[0016] Wherein, the refractive index of the first lens is greater than the refractive index of the second lens.

[0017] According to the Micro-LED display device provided by the present invention, the second lens is arranged on a side of the first lens away from the substrate.

[0018] According to the Micro-LED display device provided by the present invention, the second lens is arranged inside the first lens, and the first lens and the second lens form a core-shell structure.

[0019] According to the Micro-LED display device provided by the present invention, the refractive index of the first lens is in the range of 1.4-1.5, and the refractive index of the second lens is in the range of 1.7-2.0.

[0020] According to the Micro-LED display device provided by the present invention, the first color light is red light, the second color light is green light, and the third color light is blue light.

[0021] According to the Micro-LED display device provided by the present invention, the orthographic projection of the second epitaxial layer on the substrate is located within the orthographic projection of the first epitaxial layer on the substrate, and the orthographic projection of the third epitaxial layer on the substrate is located within the orthographic projection of the second epitaxial layer on the substrate.

[0022] According to the Micro-LED display device provided by the present invention, the Micro-LED display device further includes:

[0023] A first flat layer covering a side of the LED light-emitting layer away from the substrate, wherein a groove is provided on a surface of the first flat layer away from the substrate, and at least a portion of the double convex lens device is located in the groove; and

[0024] A second flat layer covers the first flat layer and a side of the double convex lens device away from the substrate.

[0025] The present invention provides a display panel, comprising a plurality of the above-mentioned Micro-LED display devices distributed in an array.

[0026] Beneficial effect: In the Micro-LED display device and display panel provided by the present invention, a double convex lens structure is arranged on the side of the LED light-emitting layer away from the integrated circuit, and the collimation characteristics of the double convex lens device on the light beam are utilized, so that the light emitted by the LED light-emitting layer can be converted into collimated light for emission. There is no need to set up an additional optical device outside the Micro-LED display device to shape the light, thereby avoiding the loss of light in the optical device, improving the light conversion efficiency of the entire optical system, reducing the weight of the module, and facilitating the realization of a lightweight module. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 A schematic diagram of a first cross-sectional structure of a Micro-LED display device provided in an embodiment of the present invention;

[0029] Figure 2 A schematic diagram of a second cross-sectional structure of a Micro-LED display device provided in an embodiment of the present invention;

[0030] Figure 3 for Figure 2 Schematic diagram of part of the optical path of the Micro-LED display device;

[0031] Figure 4 A schematic diagram of a third cross-sectional structure of a Micro-LED display device provided in an embodiment of the present invention;

[0032] Figure 5 for Figure 4 Schematic diagram of part of the optical path of the Micro-LED display device;

[0033] Fig. 6A A schematic diagram of a first cross-sectional structure of a biconvex lens device provided in an embodiment of the present invention;

[0034] Figure 6B A schematic diagram of a second cross-sectional structure of a biconvex lens device provided in an embodiment of the present invention;

[0035] Figure 6C A schematic diagram of a third cross-sectional structure of a double convex lens device provided in an embodiment of the present invention;

[0036] Fig.6D A schematic diagram of a fourth cross-sectional structure of a double convex lens device provided in an embodiment of the present invention;

[0037] Figure 7 A schematic diagram of a fourth cross-sectional structure of a Micro-LED display device provided in an embodiment of the present invention;

[0038] Figure 8 A flowchart of a method for preparing a Micro-LED display device provided by an embodiment of the present invention;

[0039] Figure 9A-9I A schematic diagram of the process structure of a method for preparing a Micro-LED display device provided in an embodiment of the present invention;

[0040] Fig.10 A schematic diagram of a planar structure of a display panel provided by an embodiment of the present invention.

[0041] Description of reference numerals:

[0042] 100. Micro-LED display device; 200. Display panel;

[0043] 10. substrate; 20. integrated circuit layer; 30. LED light-emitting layer; 31. first epitaxial layer; 32. second epitaxial layer; 33. third epitaxial layer; 34. first bonding layer; 35. second bonding layer; 36. third bonding layer; 37. first N-type electrode; 38. second N-type electrode; 39. third N-type electrode; 301. first substrate; 302. second substrate; 303. third substrate; 304. insulating layer; 305. common electrode; 40. double convex lens device; 41. first lens; 42. second lens; 50. first flat layer; 51. groove; 60. second flat layer; 70. first filling layer; 80. second filling layer. DETAILED DESCRIPTION

[0044] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0045] In the description of the present invention, it should be understood that the terms "length", "width", "thickness", "upper", "lower" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0046] In the present invention, unless otherwise clearly stipulated and limited, a first feature being “on” or “under” a second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them.

[0047] The embodiments of the present invention provide a Micro-LED display device and a display panel. The following are detailed descriptions of each of them. It should be noted that the description order of the following embodiments is not intended to limit the preferred order of the embodiments.

[0048] The present invention provides a Micro-LED display device and a display panel, wherein the Micro-LED display device includes a substrate, an integrated circuit layer, an LED light-emitting layer, and a double convex lens device. The integrated circuit layer is arranged on one side of the substrate. The LED light-emitting layer is arranged on one side of the integrated circuit layer and is electrically connected to the integrated circuit layer. The double convex lens device is arranged on the side of the LED light-emitting layer away from the integrated circuit, and the double convex lens device is used to convert the light emitted by the LED light-emitting layer into collimated light for emission. The present invention arranges a double convex lens structure on the side of the LED light-emitting layer away from the integrated circuit, and utilizes the collimation characteristics of the double convex lens device for the light beam, so that the light emitted by the LED light-emitting layer can be converted into collimated light for emission, and there is no need to arrange an optical device outside the Micro-LED display device to shape the light, thereby avoiding the loss of light in the optical device, improving the light conversion efficiency of the entire optical system, reducing the weight of the module, and facilitating the realization of a thin and light module.

[0049] For details, please refer to Figure 1 The Micro-LED display device 100 provided in the embodiment of the present invention includes a substrate 10, an integrated circuit layer 20, an LED light-emitting layer 30 and a double convex lens device 40. The integrated circuit layer 20 is arranged on one side of the substrate 10. The LED light-emitting layer 30 is arranged on one side of the integrated circuit layer 20 and is electrically connected to the integrated circuit layer 20. The double convex lens device 40 is arranged on the side of the LED light-emitting layer 30 away from the integrated circuit. The double convex lens device 40 is used to convert the light emitted by the LED light-emitting layer 30 into collimated light for emission. There is no need to set up an optical device outside the Micro-LED display device 100 to shape the light, thereby avoiding the loss of light in the optical device, improving the light conversion efficiency of the entire optical system, reducing the weight of the module, and facilitating the realization of a thin and light module.

[0050] Specifically, the combination of the integrated circuit layer 20 and the substrate 10 can be called an integrated circuit wafer, and the integrated circuit layer 20 includes a driver circuit system, and the driver circuit system includes a pixel driver array, and the pixel driver array includes a driving circuit for driving the LED light-emitting layer 30 to emit light.

[0051] It is understandable that the LED light emitting layer 30 emits a variety of light, including divergent light, also known as Lambert light. This type of light will narrow the light output angle after passing through the double convex lens device 40, and become collimated light and emit in parallel. In addition, the LED light emitting layer 30 also emits parallel light, and the parallel light will converge after passing through the double convex lens device 40. The most important thing is that the main purpose of setting the double convex lens device 40 in the present invention is to narrow the angle of the divergent light to form collimated light, so that the light can easily enter the optical waveguide device through a smaller light inlet, so as to smoothly carry out the subsequent optical waveguide processing, which is conducive to improving the light conversion efficiency.

[0052] In one embodiment, the LED light emitting layer 30 is a single LED wafer for emitting light of one color. Accordingly, the dual lens device collimates the light emitted by the single LED wafer. Specifically, for the entire display panel 200, multiple LED wafers are arranged at intervals on the same horizontal plane, and each pixel unit of the display panel 200 includes multiple LED wafers arranged at intervals.

[0053] For further information, see Figure 2 In another embodiment, the LED light-emitting layer 30 is a plurality of LED wafers stacked to form a full-color vertical stacking structure. The LED light-emitting layer 30 can emit light of multiple colors. Compared with the aforementioned embodiment in which the LED light-emitting layer 30 is a single LED wafer, since the plurality of LED wafers can be stacked and arranged on a vertical plane, the size of a single pixel unit of the display panel 200 can be reduced, thereby facilitating improving pixel density and resolution, which is particularly applicable to augmented / virtual reality display devices requiring high resolution.

[0054] Specifically, the LED light-emitting layer 30 includes an epitaxial stacked structure, which includes a first epitaxial layer 31, a second epitaxial layer 32, and a third epitaxial layer 33. The first epitaxial layer 31 is disposed on one side of the integrated circuit layer 20, and is used to emit a first color light; the second epitaxial layer 32 is disposed on a side of the first epitaxial layer 31 away from the substrate 10 and is bonded to the first epitaxial layer 31, and the second epitaxial layer 32 is used to emit a second color light; the third epitaxial layer 33 is disposed on a side of the second epitaxial layer 32 away from the substrate 10 and is bonded to the second epitaxial layer 32, and the third epitaxial layer 33 is used to emit a third color light.

[0055] In this embodiment, the double convex lens device 40 is disposed on a side of the third epitaxial layer 33 away from the substrate 10 , and is used to convert the first color light, the second color light and the third color light into collimated light for emission.

[0056] Please note that Figure 3 , using this full-color vertical stacking structure, the double convex lens device 40 can convert the divergent light beam emitted from the LED light emitting layer 30 into a collimated light beam for emission. However, for the parallel light beam emitted from the LED light emitting layer 30, since the parallel light beam in the same direction contains three colors, and the same material has different refractive indices for light of different wavelengths, the propagation directions of the multi-wavelength light beams will be separated after passing through the double convex lens device 40, which is the dispersion phenomenon. This will cause color aberration in the display and seriously affect the imaging quality.

[0057] In view of this, please refer to Figure 4 and Figure 5 The embodiment of the present invention overcomes the above-mentioned defects by using two materials to manufacture the biconvex lens device 40. Specifically, the biconvex lens device 40 includes a first lens 41 and a second lens 42, and the distance from the side surface of the first lens 41 close to the substrate 10 to the third epitaxial layer 33 is smaller than the distance from the side surface of the second lens 42 close to the substrate 10 to the third epitaxial layer 33. The refractive index of the first lens 41 is greater than the refractive index of the second lens 42.

[0058] It can be understood that the first lens 41 is a positive lens and the second lens 42 is a negative lens. When the light emitted by the LED light-emitting layer 30 enters the double convex lens device 40, it will first pass through the first lens 41 and then pass through the second lens 42. Since the refractive index of the first lens 41 is relatively high, the light will be focused. On the contrary, the refractive index of the second lens 42 is relatively low, which will cause the light to disperse, thereby generating a reverse dispersion effect inside the double convex lens device 40. This reverse dispersion can offset and overcome the chromatic aberration caused by the propagation of light in different media, thereby being able to produce a more realistic and detailed image, which is beneficial to improving the imaging quality. In short, the embodiment of the present invention uses a combination of the first lens 41 made of a strong dispersion material and the second lens 42 made of a weak dispersion material, so that the dispersions compensate each other, thereby achieving the purpose of eliminating chromatic aberration.

[0059] It should be noted that the present invention adopts two materials with different refractive indices as the materials of the biconvex lens. The refractive index selection of the first lens 41 and the second lens 42 is described as follows:

[0060] In the field of optics, Abbe number is usually used to indicate the dispersion strength of a material. It is called Abber in English and represented by the letter V. The reference base number generally used is the middle dispersion, which is the difference in the refractive index between cyan and red light. Abbe number Vd = (nd-1) / (nF-nC), where nd, nF and nC are the refractive indices of d-light, F-light and C-light respectively.

[0061] Among them, d light - yellow light, with a wavelength of 587.6 nanometers, is the d line in the sodium spectrum;

[0062] F light - cyan light, with a wavelength of 486.1 nanometers, is the F line in the hydrogen spectrum;

[0063] C light - red light, with a wavelength of 656.3 nanometers, is the C line in the hydrogen spectrum.

[0064] It can be seen that materials with different refractive indices have different Abbe numbers, which usually have the following corresponding relationships, as shown in Table 1:

[0065] Refractive Index Abbe number 1.56 35.5、41、43 1.6 33、40 1.67 32 1.71 37 1.74 33

[0066] Table 1

[0067] Based on this, in the embodiment of the present invention, the refractive index of the first lens 41 is in the range of 1.4-1.5, and the refractive index of the second lens 42 is in the range of 1.7-2.0. Optionally, the refractive index of the first lens 41 may be one of 1.40, 1.41, 1.42, 1.43, 1.44, 1.45, 1.46, 1.47, 1.48, 1.49 and 1.50, and the refractive index of the second lens 42 may be one of 1.70, 1.75, 1.80, 1.85, 1.90, 1.95 and 1.20.

[0068] Specifically, the material of the first lens 41 may include aluminum oxide, titanium dioxide or other organic materials with a high refractive index, and the material of the second lens 42 may include a combination of one or more of aluminum oxide, titanium dioxide, silicon dioxide and silicon nitride.

[0069] In one embodiment, see Figure 6A-6B , the second lens 42 is disposed on a side of the first lens 41 away from the substrate 10. Specifically, Fig. 6A As shown, the side surface of the second lens 42 close to the substrate 10 is attached to the side surface of the first lens 41 away from the substrate 10, and the side surface of the first lens 41 away from the substrate 10 and the side surface of the second lens 42 close to the substrate 10 together form an elliptical structure. Figure 6B As shown, a surface of the second lens 42 close to the substrate 10 is bonded to a surface of the first lens 41 away from the substrate 10 . The first lens 41 is an elliptical structure, and the second lens 42 is an arc structure.

[0070] In another embodiment, see Figure 6C-6D, the second lens 42 is disposed inside the first lens 41, and the first lens 41 and the second lens 42 form a core-shell structure. Figure 6C As shown, the second lens 42 half covers the first lens 41, and the first lens 41 and the second lens 42 together form a semi-elliptical structure. Fig.6D As shown, the second lens 42 completely covers the first lens 41 , and both the first lens 41 and the second lens 42 are elliptical structures.

[0071] It should be noted that, considering that the luminous efficiency of the red LED wafer is lower than that of the green LED wafer and the blue LED wafer, it is easy to cause color deviation. Therefore, in the embodiment of the present invention, in the LED light-emitting layer 30 adopting the full-color vertical stacking structure, the red epitaxial layer is set at the bottom. Specifically, the first color light is red light, the second color light is green light, and the third color light is blue light, that is, the first epitaxial layer 31 is a red epitaxial layer, the second epitaxial layer 32 is a green epitaxial layer, and the third epitaxial layer 33 is a blue epitaxial layer.

[0072] Thus, in the actual preparation process, due to process reasons, the red epitaxial layer can have a larger area, thereby avoiding crosstalk caused by light excitation during upward emission, which is beneficial to avoiding color deviation.

[0073] See also Figure 7 In the embodiment of the present invention, the orthographic projection of the second epitaxial layer 32 on the substrate 10 is located within the orthographic projection of the first epitaxial layer 31 on the substrate 10 , and the orthographic projection of the third epitaxial layer 33 on the substrate 10 is located within the orthographic projection of the second epitaxial layer 32 on the substrate 10 .

[0074] Furthermore, the Micro-LED display device 100 further includes a first flat layer 50 and a second flat layer 60. The first flat layer 50 covers the side of the third epitaxial layer 33 away from the substrate 10, and is used to flatten the surface of the integrated circuit layer 20. A groove 51 is provided on the surface of the first flat layer 50 away from the substrate 10, and at least a portion of the double convex lens device 40 is located in the groove 51. The second flat layer 60 covers the first flat layer 50 and the side of the double convex lens device 40 away from the substrate 10, and is used to flatten the surface of the double convex lens device 40 away from the substrate 10.

[0075] Specifically, the cross-sectional shape of the groove 51 may be an arc shape to match the outer surface of the double convex lens device 40. In the embodiment of the present invention, the maximum depth of the groove 51 is 2 micrometers to 3 micrometers.

[0076] Furthermore, the LED light-emitting layer 30 also includes a first bonding layer 34, a second bonding layer 35 and a third bonding layer 36. The first bonding layer 34 is disposed between the first epitaxial layer 31 and the integrated circuit layer 20, and is used for bonding the first epitaxial layer 31 and the integrated circuit layer 20. The second bonding layer 35 is disposed between the second epitaxial layer 32 and the first epitaxial layer 31, and is used for bonding the second epitaxial layer 32 and the first epitaxial layer 31. The third bonding layer 36 is disposed between the third epitaxial layer 33 and the second epitaxial layer 32, and is used for bonding the third epitaxial layer 33 and the second epitaxial layer 32. In this way, the first bonding layer 34, the second bonding layer 35 and the third bonding layer 36 realize the electrical connection between the pixel circuit layer and the first epitaxial layer 31, the second epitaxial layer 32 and the third epitaxial layer 33, thereby driving each epitaxial layer to emit light.

[0077] Specifically, the first bonding layer 34 is a metal bonding layer, which can be used as a reflector to reflect the light emitted by the LED light-emitting layer 30, which is beneficial to improve the light extraction efficiency. Optionally, the first bonding layer 34 includes one or more of Au-Au bonding, Au-Sn bonding, Au-In bonding, Ti-Ti bonding and Cu-Cu bonding. The thickness of the first bonding layer 34 ranges from 0.1 microns to 3 microns.

[0078] Specifically, the second bonding layer 35 and the third bonding layer 36 are transparent bonding layers, so that the light emitted by the first epitaxial layer 31 and the second epitaxial layer 32 can pass through, which is conducive to further improving the light extraction efficiency. Optionally, the second bonding layer 35 and the third bonding layer 36 include one or more of silicon dioxide, indium tin oxide and organic glue. The thickness of the second bonding layer 35 ranges from 0.1 microns to 3 microns, and the thickness of the third bonding layer 36 ranges from 0.1 microns to 3 microns.

[0079] The LED light-emitting layer 30 also includes an insulating layer 304, which covers one side of the integrated circuit layer 20, the side wall of the first bonding layer 34, the side wall of the first epitaxial layer 31, the side wall of the second bonding layer 35, the side wall of the second epitaxial layer 32, the side wall of the third bonding layer 36, the side wall of the third epitaxial layer 33 and a surface on one side away from the substrate 10.

[0080] The LED light-emitting layer 30 further includes a first N-type electrode 37, a second N-type electrode 38, and a third N-type electrode 39. One end of the first N-type electrode 37 overlaps with a side of the first epitaxial layer 31 away from the substrate 10, and the other end is electrically connected to the integrated circuit layer 20. One end of the second N-type electrode 38 overlaps with a side of the second epitaxial layer 32 away from the substrate 10. One end of the third N-type electrode 39 overlaps with a side of the third epitaxial layer 33 on the integrated circuit layer 20.

[0081] The LED light-emitting layer 30 further includes a common electrode 305 , which is located on the insulating layer 304 and connected to the first epitaxial layer 31 , the second epitaxial layer 32 and the third epitaxial layer 33 , respectively. One end of the common electrode 305 is electrically connected to the integrated circuit layer 20 .

[0082] See also Figure 8 as well as Figure 9A-9I The present invention also provides a method for preparing a Micro-LED display device 100, comprising the following steps:

[0083] Step S1, providing a substrate 10;

[0084] Step S2, forming an integrated circuit layer 20 on one side of the substrate 10;

[0085] Step S3, forming an LED light-emitting layer 30 on a side of the integrated circuit layer 20 away from the substrate 10, wherein the LED light-emitting layer 30 is electrically connected to the integrated circuit layer 20; and

[0086] Step S4, forming a double convex lens device 40 on a side of the LED light emitting layer 30 away from the substrate 10, wherein the double convex lens device 40 is used to convert the light emitted by the LED light emitting layer 30 into collimated light for outgoing emission.

[0087] It should be noted that the embodiment of the present invention is described by taking the LED light emitting layer 30 as an example in which a plurality of LED wafers are stacked to form a full-color vertical stacking structure.

[0088] For details, please refer to steps S1 and S2. Fig. 9A After step S2, the following steps are also included:

[0089] S11, preparing three types of LED wafers emitting first color light, second color light, and third color light;

[0090] S12 , stacking and bonding three types of LED wafers in sequence on a side of the integrated circuit layer 20 away from the substrate 10 .

[0091] It should be noted that the embodiment of the present invention is explained by taking the first color light being red light, the second color light being green light, and the third color light being blue light, that is, the three types of LED wafers are red LED wafers, green LED wafers, and blue LED wafers as examples.

[0092] The following specifically describes the preparation processes of the red LED wafer, the green LED wafer and the blue LED wafer in the above step S21 .

[0093] The red LED wafer includes a first substrate 301 and a first epitaxial layer 31 formed on the first substrate 301. The material of the first substrate 301 includes GaAs, and the material of the first epitaxial layer 31 includes AlGaInP / GaInP quantum well material. The red LED wafer also includes an N-type doped semiconductor layer and a P-type doped semiconductor layer, the N-type doped semiconductor layer includes GaAs, and the P-type doped semiconductor layer includes GaP material. In some embodiments, a periodic stress adjustment layer and a current diffusion layer are further grown between the N-type doped semiconductor layer and the first epitaxial layer 31, and a periodic stress adjustment layer, a current diffusion layer and a Bragg reflector (DBR) are further grown between the P-type doped semiconductor layer and the first epitaxial layer 31. Optionally, the Bragg reflector DBR can be made of multiple layers of silicon dioxide and titanium pentoxide, and by changing the thickness and number of each layer, selective reflection or transmission of light of different wavelengths can be formed.

[0094] The green LED wafer includes a second substrate 302 and a second epitaxial layer 32 formed on the second substrate 302. The second substrate 302 includes a sapphire substrate 10, and may also be a composite of one or more of GaN, AlN, Si, and SiC. The material of the second epitaxial layer 32 includes InGaN / GaN quantum well material. The green LED wafer also includes an N-type doped semiconductor layer and a P-type doped semiconductor layer, the N-type doped semiconductor layer includes GaAs, and the P-type doped semiconductor layer includes GaP material. In some embodiments, a periodic stress adjustment layer and a current diffusion layer are further grown between the N-type doped semiconductor layer and the second epitaxial layer 32, and a periodic stress adjustment layer, a current diffusion layer, and a Bragg reflection layer (DBR) are further grown between the P-type doped semiconductor layer and the second epitaxial layer 32. Optionally, the Bragg reflection layer DBR may be made of multiple layers of silicon dioxide and titanium pentoxide, and by changing the thickness and number of each layer, selective reflection or transmission of light of different wavelengths may be formed.

[0095] The blue LED wafer includes a third substrate 303 and a third epitaxial layer 33 formed on the third substrate 303. The third substrate 303 includes a sapphire substrate 10, and may also be a composite of one or more of GaN, AlN, Si, and SiC. The material of the third epitaxial layer 33 includes InGaN / GaN quantum well material. The blue LED wafer also includes an N-type doped semiconductor layer and a P-type doped semiconductor layer, the N-type doped semiconductor layer includes GaAs, and the P-type doped semiconductor layer includes GaP material. In some embodiments, a periodic stress adjustment layer and a current diffusion layer are further grown between the N-type doped semiconductor layer and the third epitaxial layer 33, and a periodic stress adjustment layer, a current diffusion layer, and a Bragg reflection layer (DBR) are further grown between the P-type doped semiconductor layer and the third epitaxial layer 33. Optionally, the Bragg reflection layer DBR may be made of multiple layers of silicon dioxide and titanium pentoxide, and by changing the thickness and number of each layer, selective reflection or transmission of light of different wavelengths may be formed.

[0096] Specifically, in the above step S22, the following steps are included:

[0097] like Fig. 9B As shown, S221, bonding the first epitaxial layer 31 of the red LED wafer to the integrated circuit, and removing the first substrate 301 of the red LED wafer.

[0098] like Fig. 9C As shown, S222, the second epitaxial layer 32 of the green LED wafer is bonded to the integrated circuit layer 20, and the second substrate 302 of the green LED wafer is removed.

[0099] like Fig.9D As shown, S223, the third epitaxial layer 33 of the blue LED wafer is bonded to the integrated circuit layer 20, and the third substrate 303 of the blue LED wafer is removed.

[0100] Optionally, in step S221 , step S222 and step S223 , the first substrate 301 , the second substrate 302 and the third substrate 303 may be removed by a laser lift-off process or wet chemical etching.

[0101] Furthermore, the above step S4 includes the following steps:

[0102] like Fig.9E As shown, S41: forming a first flat layer 50 on a side of the third epitaxial layer 33 away from the substrate 10, and providing a groove 51 on a surface of the first flat layer 50 away from the substrate 10;

[0103] like Fig.9F As shown, S42: forming a first filling layer 70 at least in the groove 51, and processing the first filling layer 70 to form a first lens 41.

[0104] like Figure 9G and Figure 9H As shown, S43: forming a second filling layer 80 on the side of the first flat layer 50 and the first lens 41 away from the substrate 10, and processing the second filling layer 80 to form a second lens 42, the first lens 41 and the second lens 42 constitute a double convex lens device 40.

[0105] like Fig.9I As shown, S44: forming a second planar layer 60 covering the first planar layer 50 and a side of the double convex lens device 40 away from the substrate 10.

[0106] Specifically, in step S41, the first planar layer 50 can be formed by plasma enhanced chemical vapor deposition (PECVD), plasma enhanced atomic layer deposition (PEALD), pulsed laser deposition (PLD), molecular beam epitaxy (MBE), etc. The groove 51 is an arc-shaped concave structure, which can be formed by etching the first planar layer 50 through exposure and development. The first lens 41 fills the groove 51, and the surface of the first lens 41 and the second lens 42 away from the substrate 10 can be planarized by chemical mechanical polishing (CMP).

[0107] See also Fig.10 The present invention further provides a display panel 200, wherein the display panel 200 includes a plurality of Micro-LED display devices 100 distributed in an array. Specifically, a display device using the display panel 200 may include a virtual reality (VR) and augmented reality (AR) device.

[0108] Beneficial effect: In the Micro-LED display device and display panel provided by the present invention, a double convex lens structure is arranged on the side of the LED light-emitting layer away from the integrated circuit, and the collimation characteristics of the double convex lens device on the light beam are utilized, so that the light emitted by the LED light-emitting layer can be converted into collimated light for emission. There is no need to set up an additional optical device outside the Micro-LED display device to shape the light, thereby avoiding the loss of light in the optical device, improving the light conversion efficiency of the entire optical system, reducing the weight of the module, and facilitating the realization of a lightweight module.

[0109] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0110] A Micro-LED display device and a display panel provided by an embodiment of the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the technical solutions and core ideas of the present invention. Ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A Micro-LED display device, characterized in that: include: substrate; An integrated circuit layer is disposed on one side of the substrate; An LED light-emitting layer is disposed on a side of the integrated circuit layer away from the substrate and is electrically connected to the integrated circuit layer; as well as The double convex lens device is arranged on a side of the LED light emitting layer away from the substrate, and the double convex lens device is used to convert the light emitted by the LED light emitting layer into collimated light for outgoing emission.

2. The Micro-LED display device according to claim 1, characterized in that: The LED light-emitting layer includes an epitaxial stacked structure, and the epitaxial stacked structure includes: A first epitaxial layer, disposed on one side of the integrated circuit layer, for emitting light of a first color; a second epitaxial layer, disposed on a side of the first epitaxial layer away from the substrate and bonded to the first epitaxial layer, the second epitaxial layer being used to emit a second color light; and A third epitaxial layer, disposed on a side of the second epitaxial layer away from the substrate and bonded to the second epitaxial layer, the third epitaxial layer being used to emit a third color light; The double convex lens device is arranged on a side of the third epitaxial layer away from the substrate, and is used for converting the first color light, the second color light and the third color light into collimated light for emission.

3. The Micro-LED display device according to claim 2, characterized in that: The double convex lens device comprises a first lens and a second lens, wherein a distance from a surface of a side of the first lens close to the substrate to the third epitaxial layer is smaller than a distance from a surface of a side of the second lens close to the substrate to the third epitaxial layer; Wherein, the refractive index of the first lens is greater than the refractive index of the second lens.

4. The Micro-LED display device according to claim 3, characterized in that: The second lens is disposed on a side of the first lens away from the substrate.

5. The Micro-LED display device according to claim 3, characterized in that: The second lens is disposed inside the first lens, and the first lens and the second lens form a core-shell structure.

6. The Micro-LED display device according to any one of claims 3 to 5, characterized in that: The refractive index of the first lens is in the range of 1.4-1.5, and the refractive index of the second lens is in the range of 1.7-2.

0.

7. The Micro-LED display device according to claim 2, characterized in that: The first color light is red light, the second color light is green light, and the third color light is blue light.

8. The Micro-LED display device according to claim 7, characterized in that: The orthographic projection of the second epitaxial layer on the substrate is located within the orthographic projection of the first epitaxial layer on the substrate, and the orthographic projection of the third epitaxial layer on the substrate is located within the orthographic projection of the second epitaxial layer on the substrate.

9. The Micro-LED display device according to claim 1, characterized in that: The Micro-LED display device further includes: A first flat layer covering a side of the LED light-emitting layer away from the substrate, wherein a groove is provided on a surface of the first flat layer away from the substrate, and at least a portion of the double convex lens device is located in the groove; and A second flat layer covers the first flat layer and a side of the double convex lens device away from the substrate.

10. A display panel, characterized in that: It comprises a plurality of Micro-LED display devices as described in any one of claims 1 to 9 distributed in an array.

Images