Miniature light emitting diode display chip, preparation method and display device

Abstract

The invention discloses a micro light-emitting diode display chip, a preparation method and a display device. Comprising a driving substrate including a plurality of contacts; the first light-emitting module is arranged on the driving substrate, and the first light-emitting module comprises a plurality of first LED units which are arranged in an array; the second light-emitting module is arranged on the driving substrate, and the second light-emitting module and the first light-emitting module are arranged at an interval; the second light-emitting module and the first light-emitting module are located on the same plane. The second light-emitting module comprises a plurality of second LED units which are arranged in an array; the second LED units are individually driven through the corresponding contacts. According to the display chip, the first light-emitting module and the second light-emitting module which are located on the same plane are arranged on the driving substrate, and the colors of light emitted by the light-emitting modules are different, so that full-color display is easier to realize, and the preparation difficulty of the miniature light-emitting display device is reduced.

Description

Technical Field

[0001] The present application belongs to the field of micro-display technology, and specifically relates to a micro light emitting diode display chip, a preparation method, and a display device. Background Art

[0002] In order to achieve color projection, the three-color light combination technology that uses red, green and blue light sources to synthesize color images has emerged. This technology allows the use of three independent light sources to control the color and brightness of each pixel, so it has the advantages of high resolution and high brightness. Micro-light emitting diode display chips not only have the characteristics of small size, but also have the advantages of high brightness, low power consumption, fast response, long life, and high light efficiency. They can be used as light sources for color projection, but in the light combination process, each independent light source is required to be precisely aligned in time and space so that they can be combined into a seamless color image. However, there is an alignment deviation of the independent light sources, which may cause problems such as color misalignment, blur or artifacts in the image. Summary of the invention

[0003] Purpose of the invention: The purpose of this application is to provide.

[0004] Technical solution: To achieve the above-mentioned invention object, the present application provides a micro light emitting diode display chip, comprising:

[0005] A driving substrate, wherein the driving substrate comprises a plurality of contacts;

[0006] A first light-emitting module is provided on the driving substrate, wherein the first light-emitting module comprises a plurality of first LED units arranged in an array; the first LED units are driven individually through the corresponding contacts;

[0007] A second light-emitting module is disposed on the driving substrate and spaced apart from the first light-emitting module; the second light-emitting module and the first light-emitting module are located in the same plane; the second light-emitting module includes a plurality of second LED units arranged in an array; the second LED units are driven individually through the corresponding contacts;

[0008] All the first LED units in the first light-emitting module emit light of the same color, all the second LED units in the second light-emitting module emit light of the same color, and the color of the light emitted by the first LED unit is different from the color of the light emitted by the second LED unit.

[0009] In some embodiments, it also includes:

[0010] A third light-emitting module is disposed on the driving substrate and is spaced apart from the second light-emitting module on a side away from the first light-emitting module; the third light-emitting module, the second light-emitting module and the first light-emitting module are all located in the same plane; the third light-emitting module includes a plurality of third LED units arranged in an array; the third LED unit is driven individually through the corresponding contact points;

[0011] All third LED units in the third light-emitting module emit light of the same color, and the color of the light emitted by the third LED unit is different from the color of the light emitted by at least one of the first LED unit and the second LED unit.

[0012] In some embodiments, it also includes:

[0013] A bonding layer is provided on the driving substrate; any one of the first LED unit, the second LED unit, and the third LED unit is electrically connected to the bonding layer.

[0014] In some embodiments, the first light emitting module further includes:

[0015] A first passivation layer, wherein the first passivation layer covers a side surface of the bonding layer and a side surface of the first LED unit;

[0016] a first electrode layer, wherein the first electrode layer covers a side of the first passivation layer away from the first LED unit, and the first passivation layer electrically isolates the first electrode layer from any one of the first LED unit and the bonding layer; the first electrode layer is electrically connected to the corresponding contacts and a portion of the top surface of the first LED unit respectively;

[0017] The second light emitting module further includes:

[0018] a second passivation layer, wherein the second passivation layer covers a side surface of the bonding layer and a side surface of the second LED unit;

[0019] a second electrode layer, wherein the second electrode layer covers a side of the second passivation layer away from the second LED unit, and the second passivation layer electrically isolates the second electrode layer from any one of the second LED unit and the bonding layer; the second electrode layer is electrically connected to the corresponding contacts and a portion of the top surface of the second LED unit respectively;

[0020] The third light emitting module further includes:

[0021] a third passivation layer, the third passivation layer covering a side surface of the bonding layer and a side surface of the third LED unit;

[0022] A third electrode layer, wherein the third electrode layer covers a side of the third passivation layer away from the third LED unit, and the third passivation layer electrically isolates the third electrode layer from the third LED unit and any one of the bonding layers; the third electrode layer is electrically connected to the corresponding contacts and a portion of the top surface of the third LED unit, respectively.

[0023] In some embodiments, the driving substrate has a length direction; the first light-emitting module, the second light-emitting module, and the third light-emitting module are sequentially arranged at intervals along the length direction;

[0024] There is a minimum distance A between the first light-emitting module and the second light-emitting module along the length direction, and there is a minimum distance B between the second light-emitting module and the third light-emitting module along the length direction, satisfying: 0.1 micron ≤ A ≤ 10000 micron, and 0.1 micron ≤ B ≤ 10000 micron.

[0025] In some embodiments, the driving substrate further has a width direction perpendicular to the length direction;

[0026] In the first light-emitting module, a plurality of the first LED units are arranged at intervals along the length direction and the width direction, respectively, and a minimum distance a1 is provided between adjacent first LED units along the length direction, and a minimum distance a2 is provided between adjacent first LED units along the width direction;

[0027] In the second light-emitting module, a plurality of the second LED units are arranged at intervals along the length direction and the width direction, respectively, and a minimum distance b1 is provided between adjacent second LED units along the length direction, and a minimum distance b2 is provided between adjacent second LED units along the width direction;

[0028] In the third light-emitting module, a plurality of the third LED units are arranged at intervals along the length direction and the width direction, respectively, and a minimum distance c1 is provided between adjacent third LED units along the length direction, and a minimum distance c2 is provided between adjacent third LED units along the width direction;

[0029] The micro light emitting diode display chip further satisfies at least one of the following characteristics:

[0030] a) 0.1 micron ≤ a1 ≤ 100 microns;

[0031] b) 0.1 micron ≤ a2 ≤ 100 microns;

[0032] c) 0.1 micron ≤ b1 ≤ 100 microns;

[0033] d) 0.1 micron ≤ b2 ≤ 100 microns;

[0034] e) 0.1 micron ≤ c1 ≤ 100 microns;

[0035] f)0.1 micron ≤ c2 ≤ 100 microns.

[0036] In some embodiments, at least one of the first LED unit, the second LED unit, and the third LED unit is a step structure, and the step structure includes a first doped semiconductor layer, a second doped semiconductor layer, and an active layer located therebetween; the step structure disconnects and electrically isolates the adjacent second doped semiconductor layer, the active layer, and the first doped semiconductor layer from each other; and the contact is electrically connected to the corresponding first doped semiconductor layer.

[0037] In some embodiments, the size of any one of the first LED unit, the second LED unit, and the third LED unit is 1-10 μm; or

[0038] The driving substrate is a silicon-based CMOS driving board or a thin film field effect transistor driving board.

[0039] In some embodiments, the present application also provides a method for preparing a micro light emitting diode display chip, comprising:

[0040] Providing a driving substrate, and dividing the driving substrate into at least a first light-emitting area and a second light-emitting area, wherein the driving substrate includes a plurality of contacts;

[0041] forming a first epitaxial layer on the first light emitting region;

[0042] forming a second epitaxial layer on the second light emitting region;

[0043] Processing the first epitaxial layer located in the first light-emitting area to form a first light-emitting module, wherein the first light-emitting module includes a plurality of first LED units arranged in an array, and the first LED units are driven individually through the corresponding contacts;

[0044] Processing the second epitaxial layer located in the second light-emitting area to form a second light-emitting module, the second light-emitting module and the first light-emitting module are located in the same plane and are spaced apart; the second light-emitting module includes a plurality of second LED units arranged in an array, and the second LED units are driven individually through the corresponding contacts;

[0045] All the first LED units in the first light-emitting module emit light of the same color, all the second LED units in the second light-emitting module emit light of the same color, and the color of the light emitted by the first LED unit is different from the color of the light emitted by the second LED unit.

[0046] In some embodiments, the driving substrate is further separated into a third light emitting area, and after the second epitaxial layer is formed on the second light emitting area, the driving substrate further includes:

[0047] forming a third epitaxial layer on the third light emitting region;

[0048] Processing the third epitaxial layer located in the third light-emitting area to form a third light-emitting module, the third light-emitting module is spaced apart from the side of the second light-emitting module away from the first light-emitting module, and is located in the same plane as the second light-emitting module and the first light-emitting module; the third light-emitting module includes a plurality of third LED units arranged in an array, and the third LED units are driven individually through the corresponding contacts;

[0049] All third LED units in the third light-emitting module emit light of the same color, and the color of the light emitted by the third LED unit is different from the color of the light emitted by at least one of the first LED unit and the second LED unit.

[0050] In some embodiments, the step of forming the first epitaxial layer on the first light emitting region further comprises:

[0051] Providing a first substrate, and forming a first epitaxial layer on the first substrate;

[0052] forming a bonding layer on the driving substrate and / or the first epitaxial layer, bonding the driving substrate and the first epitaxial layer through the bonding layer to form a first epitaxial layer on the driving substrate, and removing the first substrate;

[0053] Etching the first epitaxial layer to remove the first epitaxial layer located in the second light emitting region and the third light emitting region, so as to retain the first epitaxial layer located on the first light emitting region;

[0054] The step of forming the second epitaxial layer on the second light emitting region further comprises:

[0055] Providing a second substrate, and forming a second epitaxial layer on the second substrate;

[0056] Etching the second epitaxial layer to remove the second epitaxial layer corresponding to the first light emitting area and the second epitaxial layer corresponding to the third light emitting area, and retaining the second epitaxial layer corresponding to the second light emitting area;

[0057] Bonding the driving substrate and the second epitaxial layer through the bonding layer to form a second epitaxial layer on the second light emitting region of the driving substrate, and removing the second substrate;

[0058] The step of forming the third epitaxial layer on the third light emitting region further comprises:

[0059] Providing a third substrate, and forming a third epitaxial layer on the third substrate;

[0060] forming a bonding layer on the third epitaxial layer;

[0061] Etching the third epitaxial layer to remove the third epitaxial layer corresponding to the first light emitting region and the third epitaxial layer corresponding to the second light emitting region, and retaining the third epitaxial layer corresponding to the third light emitting region;

[0062] The driving substrate and the third epitaxial layer are bonded via the bonding layer to form a third epitaxial layer on the third light emitting region of the driving substrate, and the third substrate is removed.

[0063] In some embodiments, the step of processing the first epitaxial layer located in the first light emitting region to form the first light emitting module further includes:

[0064] Etching the first epitaxial layer to form a plurality of the first LED units, wherein the first LED unit array is arranged on the bonding layer;

[0065] forming a first passivation layer on a side surface of the first LED unit and a side surface of the bonding layer;

[0066] A first electrode layer is formed on a side of the first passivation layer away from the first LED unit, the first electrode layer is electrically connected to the corresponding contacts and a portion of the top surface of the first LED unit, and the first passivation layer electrically isolates the first electrode layer from the first LED unit and any one of the bonding layers.

[0067] In some embodiments, the step of processing the second epitaxial layer located in the second light emitting region to form a second light emitting module further includes:

[0068] Etching the second epitaxial layer to form a plurality of second LED units, wherein the second LED unit array is arranged on the bonding layer;

[0069] forming a second passivation layer on a side surface of the second LED unit and a side surface of the bonding layer;

[0070] A second electrode layer is formed on a side of the second passivation layer away from the second LED unit, and the second electrode layer is electrically connected to the corresponding contacts and a portion of the top surface of the second LED unit, respectively. The second passivation layer electrically isolates the second electrode layer from the second LED unit and any one of the bonding layer.

[0071] In some embodiments, the step of processing the third epitaxial layer located in the third light emitting region to form a third light emitting module further includes:

[0072] Etching the third epitaxial layer to form a plurality of the third LED units, wherein the third LED unit array is arranged on the bonding layer;

[0073] forming a third passivation layer on a side surface of the third LED unit and a side surface of the bonding layer;

[0074] A third electrode layer is formed on a side of the third passivation layer away from the third LED unit, and the third electrode layer is electrically connected to the corresponding contacts and a portion of the top surface of the third LED unit, respectively. The third passivation layer electrically isolates the third electrode layer from the third LED unit and any one of the bonding layers.

[0075] In some embodiments, the present application also provides a display device, including the micro-light emitting diode display chip; or, including the micro-light emitting diode display chip prepared by the method described.

[0076] In some embodiments, the light emitting direction of the first light emitting module and / or the second light emitting module is a first direction, the direction in which the first light emitting module and the second light emitting module are spaced apart is a second direction, and the first direction intersects the second direction; the display device further includes:

[0077] A first light combining module, wherein the first light combining module and the first light emitting module are arranged correspondingly in the first direction, and the first light combining module is used for converting the light emitted by the first light emitting module from the first direction to be emitted in the second direction;

[0078] A second light combining module, wherein the second light combining module and the first light combining module are spaced apart in the second direction and are located in the same plane; the second light combining module and the second light emitting module are correspondingly arranged in the first direction, and the second light combining module is used for converting the light emitted by the second light emitting module from the first direction to the second direction, and allowing the light emitted by the first light emitting module to pass through.

[0079] In some embodiments, the display device further comprises:

[0080] A third light combining module, the third light combining module is spaced along the second direction at a side of the second light combining module away from the first light combining module, the third light combining module, the first light combining module and the second light combining module are located in the same plane; the third light combining module and the third light emitting module are correspondingly arranged in the first direction, the third light combining module is used for converting the light emitted by the third light emitting module from the first direction to the second direction, and allowing the light emitted by the first light emitting module and the second light emitting module to pass through.

[0081] In some embodiments, the first light combining module has a first optical film facing the first light emitting module; the orthographic projection of the first optical film on the driving substrate along the first direction covers the first light emitting module;

[0082] The second light combining module has a second optical film facing the second light emitting module; the orthographic projection of the second optical film on the driving substrate along the first direction covers the second light emitting module;

[0083] The third light combining module has a third optical film facing the third light emitting module; the orthographic projection of the third optical film on the driving substrate along the first direction covers the third light emitting module.

[0084] In some embodiments, the first optical film is inclined relative to the surface of the first light-emitting module;

[0085] The second optical film is inclined relative to the surface of the second light-emitting module;

[0086] The third optical film is inclined relative to the surface of the third light-emitting module;

[0087] Wherein, the first light emitting surface, the second optical film, and the third optical film are arranged parallel to each other.

[0088] In some embodiments, the first doped semiconductor layer is a p-type semiconductor layer, and the second doped semiconductor layer is an n-type semiconductor layer.

[0089] In some embodiments, an active layer is further provided between the first doped semiconductor layer and the second doped semiconductor layer. The active layer may specifically be a multi-quantum well structure for confining electron and hole carriers to the quantum well region. When electrons and holes recombine, the carriers undergo radiative recombination and emit photons, thereby converting electrical energy into light energy.

[0090] Beneficial effects: Compared with the prior art, the micro-light emitting diode display chip of the present application comprises: a driving substrate, the driving substrate comprises a plurality of contacts; a first light-emitting module, arranged on the driving substrate, the first light-emitting module comprises a plurality of first LED units arranged in an array; the first LED unit is driven individually through corresponding contacts; a second light-emitting module, arranged on the driving substrate and spaced apart from the first light-emitting module; the second light-emitting module and the first light-emitting module are located in the same plane; the second light-emitting module comprises a plurality of second LED units arranged in an array; the second LED unit is driven individually through corresponding contacts; wherein all the first LED units in the first light-emitting module emit light of the same color, all the second LED units in the second light-emitting module emit light of the same color, and the color of the light emitted by the first LED unit is different from the color of the light emitted by the second LED unit. In the display chip of the present application, the first light-emitting module and the second light-emitting module located in the same plane are arranged on the driving substrate, and the color of the light emitted by each light-emitting module is different, so that full-color display is easier to achieve, and the difficulty of preparing micro-light emitting display devices is reduced.

[0091] The preparation method of the micro light emitting diode display chip of the present application includes: providing a driving substrate, and separating the driving substrate into at least a first light emitting area and a second light emitting area, the driving substrate includes a plurality of contacts; forming a first epitaxial layer on the first light emitting area; forming a second epitaxial layer on the second light emitting area; processing the first epitaxial layer located in the first light emitting area to form a first light emitting module, the first light emitting module includes a plurality of first LED units arranged in an array, and the first LED unit is driven individually through corresponding contacts; processing the second epitaxial layer located in the second light emitting area to form a second light emitting module, the second light emitting module and the first light emitting module are located in the same plane and arranged at intervals; the second light emitting module includes a plurality of second LED units arranged in an array, and the second LED unit is driven individually through corresponding contacts; wherein all the first LED units in the first light emitting module emit light of the same color, and all the second LED units in the second light emitting module emit light of the same color, and the color of the light emitted by the first LED unit is different from the color of the light emitted by the second LED unit. The preparation method of the present application sets a light emitting module capable of emitting different light colors on the same plane of the driving substrate, realizes the multi-color display of the chip, and can improve the compactness and space utilization of the chip.

[0092] A display device of the present application includes a micro light-emitting diode display chip, a first light-combining module and a second light-combining module; wherein, the light-emitting direction of the first light-emitting module and / or the second light-emitting module is a first direction, the direction in which the first light-emitting module and the second light-emitting module are spaced apart is a second direction, and the first direction intersects with the second direction; the first light-combining module and the first light-emitting module are arranged correspondingly in the first direction, and the first light-combining module is used to convert the light emitted by the first light-emitting module from the first direction to the second direction; the second light-combining module and the first light-combining module are spaced apart in the second direction and are located in the same plane; the second light-combining module and the second light-emitting module are arranged correspondingly in the first direction, and the second light-combining module is used to convert the light emitted by the second light-emitting module from the first direction to the second direction, and allow the light emitted by the first light-emitting module to pass through. The display device of the present application arranges light-emitting modules that emit light of different colors on the same driving substrate, so that the light output of the light-emitting modules is aligned on the surface along the second direction. It is only necessary to adjust the angle and the front-to-back distance of the first light-combining module and the second light-combining module to complete the light combination of multiple colors. Compared with the light-combining structure of multiple independent display chips through a prism, the alignment difficulty of the present application is greatly improved, and the structure of the light-combining module is simpler, and it has a wide range of application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0093] The technical solutions and other beneficial effects of the present invention will be made apparent by describing in detail the specific embodiments of the present invention in conjunction with the accompanying drawings.

[0094] Figure 1 A top view of a micro light emitting diode display chip provided in an embodiment of the present application is shown;

[0095] Figure 2 A cross-sectional schematic diagram of a micro light emitting diode display chip provided in an embodiment of the present application is shown;

[0096] Figure 3 A schematic cross-sectional view of a driving substrate provided in an embodiment of the present application is shown;

[0097] Figure 4 A cross-sectional schematic diagram of a first substrate provided in an embodiment of the present application is shown;

[0098] Figure 5 A schematic diagram showing bonding of the first substrate to the driving substrate is shown;

[0099] Figure 6 A schematic structural diagram showing the removal of the first substrate after the first substrate is bonded to the drive substrate;

[0100] Figure 7 A schematic diagram showing etching and removing the first epitaxial layer located in the second light emitting region and the third light emitting region;

[0101] Figure 8 A schematic structural diagram of forming a first epitaxial layer on a first light emitting region is shown;

[0102] Fig. 9 A cross-sectional schematic diagram of a second substrate provided in an embodiment of the present application is shown;

[0103] Fig.10 A schematic diagram showing etching and removing the second epitaxial layer corresponding to the first light emitting region and the second epitaxial layer corresponding to the third light emitting region;

[0104] Fig.11 A schematic diagram showing bonding of the second substrate to the driving substrate is shown;

[0105] Fig.12 A schematic structural diagram of forming a second epitaxial layer on the second light emitting region is shown;

[0106] Fig.13 A schematic cross-sectional view of a third substrate provided in an embodiment of the present application is shown;

[0107] Fig.14 A schematic diagram showing etching and removing the third epitaxial layer corresponding to the first light emitting region and the third epitaxial layer corresponding to the second light emitting region;

[0108] Fig.15 A schematic diagram showing bonding of the third substrate to the driving substrate is shown;

[0109] Fig.16 A schematic structural diagram showing a third epitaxial layer formed on a third light emitting region;

[0110] Fig.17 It shows a schematic diagram of the structure of processing to form a first LED unit, a second LED unit and a third LED unit;

[0111] Fig.18 A schematic diagram of the structure of a display device provided in an embodiment of the present application is shown;

[0112] Fig.19 A schematic diagram of the light combining principle of a display device is shown;

[0113] Figure numerals: 1-driving substrate, 100-common contact, 101-contact, 102-first doped semiconductor layer, 103-second doped semiconductor layer, 104-active layer, 2-first light-emitting module, 21-first LED unit, 22-first passivation layer, 23-first electrode layer, 3-second light-emitting module, 31-second LED unit, 32-second passivation layer, 33-second electrode layer, 4-third light-emitting module, 41-third LED unit, 42-third Passivation layer, 43-third electrode layer, 5-bonding layer, 6-first substrate, 61-first epitaxial layer, 7-second substrate, 71-second epitaxial layer, 8-third substrate, 81-third epitaxial layer, 9-mask layer, 200-first light-emitting area, 300-second light-emitting area, 400-third light-emitting area, 20-first light-combining module, 30-second light-combining module, 40-third light-combining module, 201-first optical film, 301-second optical film, 401-third optical film. DETAILED DESCRIPTION

[0114] 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.

[0115] The disclosure of the present invention provides many different embodiments or examples to realize different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described in the present invention. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplicity and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides various specific examples of processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0116] Generally, the terms may be understood at least in part based on the usage of the above invention. For example, the term "one or more" used in the present invention may be used to describe any component, structure or feature in the singular form, or may be used to describe a combination of components, structures or features in the plural form, depending at least in part on the above invention. Similarly, terms such as "one", "an" or "the" may also be understood at least in part to convey singular usage or to convey plural usage depending at least in part on the above invention. In addition, the term "based on..." may be understood to not necessarily be intended to convey a set of exclusive factors, but may instead allow for the presence of additional factors that do not necessarily have to be explicitly described, depending at least in part on the above invention.

[0117] It should be easily understood that the meanings of “on,” “over,” and “on…” in the present invention should be interpreted in the broadest manner, so that “on…” means not only “directly on something,” but also means “on something” including the presence of intermediate components or layers therebetween, and “on something” or “on something” means not only “on something” or “on something,” but also includes the meaning of “on something” or “on something” without any intermediate components or layers therebetween.

[0118] Additionally, for ease of description, spatially relative terms such as "below," "beneath," "lower," "above," "upper," etc. may be used herein to describe the relationship of one element or component to another element or component as shown in the drawings. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the drawings. The device may be otherwise oriented, rotated 90 degrees or at other orientations, and the spatially relative descriptors used herein may likewise be interpreted accordingly.

[0119] The term "layer" used in the present invention refers to a material portion including an area with a certain thickness. The layer can extend over the entire lower or upper structure, or can have a degree less than the scope of the lower or upper structure. In addition, the layer can be a region of a homogeneous or inhomogeneous continuous structure, and its thickness is less than the thickness of the continuous structure. For example, the layer can be located between the top surface and the bottom surface of the continuous structure or between any pair of horizontal planes therebetween. The layer can extend horizontally, vertically and / or along a tapered surface. The substrate can be a layer, one or more layers can be included therein, and / or one or more layers can be provided thereon, above and / or below. A layer can include multiple layers. For example, the semiconductor layer can include one or more doped or undoped semiconductor layers, and can have the same or different materials.

[0120] See also Figure 1 and Figure 2The present embodiment provides a micro light emitting diode display chip, comprising: a driving substrate 1, the driving substrate 1 comprising a plurality of contacts 101; a first light emitting module 2, arranged on the driving substrate 1, the first light emitting module 2 comprising a plurality of first LED units 21 arranged in an array; the first LED unit 21 is driven individually through corresponding contacts; a second light emitting module 3, arranged on the driving substrate 1 and spaced apart from the first light emitting module 2; the second light emitting module 3 and the first light emitting module 2 are located in the same plane; the second light emitting module 3 comprises a plurality of second LED units 31 arranged in an array; the second LED unit 31 is driven individually through corresponding contacts 101; wherein, all the first LED units 21 in the first light emitting module 2 emit light of the same color, all the second LED units 31 in the second light emitting module 3 emit light of the same color, and the color of the light emitted by the first LED unit 21 is different from the color of the light emitted by the second LED unit 31.

[0121] It is understandable that in the display chip of the present application, the first light-emitting module 2 and the second light-emitting module 3 located on the same plane are arranged on the driving substrate 1, making the entire display system more compact and simplified; since the colors of light emitted by each light-emitting module are different, full-color display is easier to achieve, reducing the difficulty of preparing micro-light-emitting display devices. The first LED unit 21 and the second LED unit 31 are driven separately through the corresponding contacts 101. This independent drive design can reduce mutual interference and influence, and improve the accuracy and stability of bonding.

[0122] In some embodiments, see further Figure 1 and Figure 2 The micro light emitting diode display chip also includes: a third light emitting module 4, which is arranged on the driving substrate 1 and is spaced apart from the second light emitting module 3 on a side away from the first light emitting module 2; the third light emitting module 4 and the second light emitting module 3 and the first light emitting module 2 are all located in the same plane; the third light emitting module 4 includes a plurality of third LED units 41 arranged in an array; the third LED units 41 are driven individually through corresponding contacts 101; wherein, all third LED units 41 in the third light emitting module 4 emit light of the same color, and the color of the light emitted by the third LED unit 41 is different from the color of the light emitted by at least one of the first LED unit 21 and the second LED unit 31.

[0123] It is understandable that the light-emitting types of the display chip can be further expanded to achieve full-color display by setting the third light-emitting module 4. The third light-emitting module 4, the second light-emitting module 3 and the first light-emitting module 2 are all located on the same plane, which can further reduce the connection and wiring between components and optimize the compactness of the structure.

[0124] In some embodiments, the “~” symbol in the drawings represents multiple omitted repeating structures, and multiple specifically refers to a number greater than or equal to 2.

[0125] In some embodiments, see further Figure 2 , further comprising: a bonding layer 5, which is disposed on the driving substrate 1; any one of the first LED unit 21, the second LED unit 31, and the third LED unit 41 is electrically connected to the bonding layer 5. The bonding layer 5 is an adhesive material layer, and can also be electrically connected to the first LED unit 21, the second LED unit 31, and the third LED unit 41 to play a role of electrical conduction. The material of the bonding layer 5 is metal or metal alloy. In some embodiments, the bonding layer 5 may include Au, Ag, Cu, Al, and alloys thereof, but is not limited thereto.

[0126] In some embodiments, see further Figure 2 The first light-emitting module 2 also includes: a first passivation layer 22, the first passivation layer 22 covers the side of the bonding layer 5 and the side of the first LED unit 21; a first electrode layer 23, the first electrode layer 23 covers the side of the first passivation layer 22 away from the first LED unit 21, and the first passivation layer 22 electrically isolates the first electrode layer 23 from any one of the first LED unit 21 and the bonding layer 5; the first electrode layer 23 is electrically connected to the corresponding contacts 101 and a portion of the top surface of the first LED unit 21, respectively.

[0127] In some embodiments, see further Figure 2 The second light-emitting module 3 also includes: a second passivation layer 32, the second passivation layer 32 covers the side of the bonding layer 5 and the side of the second LED unit 31; a second electrode layer 33, the second electrode layer 33 covers the side of the second passivation layer 32 away from the second LED unit 31, and the second passivation layer 32 electrically isolates the second electrode layer 33 from any one of the second LED unit 31 and the bonding layer 5; the second electrode layer 33 is electrically connected to the corresponding contacts 101 and a portion of the top surface of the second LED unit 31, respectively.

[0128] In some embodiments, see further Figure 2 The third light-emitting module 4 also includes: a third passivation layer 42, the third passivation layer 42 covers the side of the bonding layer 5 and the side of the third LED unit 41; a third electrode layer 43, the third electrode layer 43 covers the side of the third passivation layer 42 away from the third LED unit 41, and the third passivation layer 42 electrically isolates the third electrode layer 43 from any one of the third LED unit 41 and the bonding layer 5; the third electrode layer 43 is electrically connected to the corresponding contacts 101 and a portion of the top surface of the third LED unit 41, respectively.

[0129] In some embodiments, the materials of the first passivation layer 22, the second passivation layer 32 and the third passivation layer 42 are selected from inorganic materials or organic materials to isolate and protect the corresponding LED units. The inorganic materials include any one or a combination of SiO2, Al2O3, ZrO2, TiO2, Si3N4, HfO2; the organic materials include any one or a combination of black matrix photoresist, color filter photoresist, polyimide, barrier glue (BANK), overcoat glue, near-ultraviolet negative photoresist, and styrene.

[0130] In some embodiments, the material of the first electrode layer 23 , the second electrode layer 33 , and the third electrode layer 43 is at least one of indium tin oxide, Cr, Ti, Pt, Au, Al, Cu, Ge, or Ni.

[0131] In some embodiments, see further Figure 1 , the driving substrate 1 has a length direction X; the first light-emitting module 2, the second light-emitting module 3, and the third light-emitting module 4 are sequentially arranged at intervals along the length direction X;

[0132] There is a minimum distance A between the first light-emitting module 2 and the second light-emitting module 3 along the length direction X, and there is a minimum distance B between the second light-emitting module 3 and the third light-emitting module 4 along the length direction X, satisfying: 10 -6 ≤A / B≤10 6 .

[0133] In some embodiments, the range of A / B can be 10 -6 , 10 -5 , 10 -4 , 10 -3 , 10 -2 , 10 -1 , 1, 10, 100, 1000, 10 4 , 10 5 , 10 6 Any value or range between any two values ​​in . It can be understood that when 10 is satisfied -6 ≤A / B≤10 6 When the range is within the range of , it can be ensured that the first light-emitting module 2, the second light-emitting module 3 and the third light-emitting module 4 realize independent light emission and the emitted lights will not interfere with each other to affect the light extraction efficiency.

[0134] In some embodiments, the minimum distance A between the first light-emitting module 2 and the second light-emitting module 3 along the length direction X further satisfies: 0.1 micron ≤ A ≤ 10000 microns. In some other embodiments, A further satisfies: 1 micron ≤ A ≤ 1000 microns. In some other embodiments, A further satisfies: 10 microns ≤ A ≤ 100 microns.

[0135] In some embodiments, the minimum distance B between the second light-emitting module 3 and the third light-emitting module 4 along the length direction X further satisfies: 0.1 micron ≤ B ≤ 10000 microns. In some other embodiments, B further satisfies: 1 micron ≤ B ≤ 1000 microns. In some other embodiments, B further satisfies: 10 microns ≤ B ≤ 100 microns.

[0136] In some embodiments, see further Figure 1 , the driving substrate 1 also has a width direction Y perpendicular to the length direction X; in the first light-emitting module 2, a plurality of first LED 21 units are arranged at intervals along the length direction X and the width direction Y, respectively, and adjacent first LED units 21 have a minimum distance a1 along the length direction X, and adjacent first LED units 21 have a minimum distance a2 along the width direction Y, satisfying: 0.1 micron ≤ a1 ≤ 100 microns, and 0.1 micron ≤ a2 ≤ 100 microns. It can be understood that when the above range is met, the first LED units 21 can be ensured to be compactly arranged without affecting each other's light-emitting effects, thereby avoiding light crosstalk. In some other embodiments, it further satisfies: 1 micron ≤ a1 ≤ 10 microns, and 1 micron ≤ a2 ≤ 10 microns.

[0137] In some embodiments, see further Figure 1 In the second light-emitting module 3, a plurality of second LED units 31 are arranged at intervals along the length direction X and the width direction Y, respectively. Adjacent second LED units 31 have a minimum distance b1 along the length direction X, and adjacent second LED units 31 have a minimum distance b2 along the width direction Y, satisfying: 0.1 micron ≤ b1 ≤ 100 microns, and 0.1 micron ≤ b2 ≤ 100 microns. It can be understood that when the above range is met, the second LED units 31 can be arranged compactly without affecting each other's light-emitting effects, avoiding light crosstalk. In some other embodiments, it further satisfies: 1 micron ≤ b1 ≤ 10 microns, and 1 micron ≤ b2 ≤ 10 microns.

[0138] In some embodiments, see further Figure 1 In the third light-emitting module 4, a plurality of third LED units 41 are arranged at intervals along the length direction X and the width direction Y, respectively. Adjacent third LED units 41 have a minimum distance c1 along the length direction X, and adjacent third LED units 42 have a minimum distance c2 along the width direction Y, satisfying: 0.1 micron ≤ c1 ≤ 100 microns, and 0.1 micron ≤ c2 ≤ 100 microns. It can be understood that when the above range is met, the third LED units 42 can be arranged compactly without affecting each other's light-emitting effects, thereby avoiding light crosstalk. In some other embodiments, it further satisfies: 1 micron ≤ c1 ≤ 10 microns, and 1 micron ≤ c2 ≤ 10 microns.

[0139] In some embodiments, see Fig.16 At least one of the first LED unit 21, the second LED unit 31, and the third LED unit 41 is a step structure, and the step structure includes a first doped semiconductor layer 102, a second doped semiconductor layer 103, and an active layer 104 located therebetween; the step structure disconnects and electrically isolates the adjacent second doped semiconductor layer 103, the active layer 104, and the first doped semiconductor layer 102; and the contact 101 is electrically connected to the corresponding first doped semiconductor layer 102. It can be understood that the step structure can prevent the currents between adjacent LED units from interfering with each other, thereby improving the independence and stability of the LED units.

[0140] In some embodiments, at least one of the first LED unit 21, the second LED unit 31, and the third LED unit 41 may be in a trapezoidal structure. That is, the side wall of at least one of the first LED unit 21, the second LED unit 31, and the third LED unit 41 may be an inclined surface, and the angle between the side wall and the top surface may be an obtuse angle, thereby improving the focusing effect of the LED unit. It should be understood that at least one of the first LED unit 21, the second LED unit 31, and the third LED unit 41 may also be in a columnar structure, in which case the angle between the side wall and the top surface of the LED unit is a right angle.

[0141] In some embodiments, the first doped semiconductor layer 102 and the second doped semiconductor layer 104 may include one or more layers based on IIVI materials (such as ZnSe or ZnO) or IIIV nitride materials (such as GaN, AlN, InN, InGaN, GaP, AlInGaP, AlGaAs and alloys thereof).

[0142] In some embodiments, the first doped semiconductor layer 102 may be p-type GaN. In some embodiments, the first doped semiconductor layer 102 may be p-type InGaN. In some embodiments, the first doped semiconductor layer 102 may be p-type AlInGaP.

[0143] In some embodiments, the second doped semiconductor layer 104 may be n-type GaN. In some embodiments, the second doped semiconductor layer 104 may be n-type InGaN. In some embodiments, the second doped semiconductor layer 104 may be n-type AlInGaP.

[0144] In some embodiments, the active layer 103 is an active region of the LED unit. The active layer 103 is arranged between the first doped semiconductor layer 102 and the second doped semiconductor layer 104 and provides light. The active layer 103 is a layer that recombine holes and electrons provided from the first doped semiconductor 102 and the second doped semiconductor layer 104, respectively, and outputs light of a specific wavelength, and the active layer 103 may have a single quantum well structure or a multiple quantum well (MQW) structure and a well layer and a barrier layer alternately stacked.

[0145] In some embodiments, the size of any one of the first LED unit 21, the second LED unit 31, and the third LED unit 41 is 1 to 10 μm; for example, the size is any value of 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, or a range between any two values.

[0146] In some embodiments, the driving substrate 1 is a silicon-based CMOS driving board or a thin film field effect transistor driving board.

[0147] In some embodiments, any one of the first LED unit 21 , the second LED unit 31 , and the third LED unit 41 can emit any one of red light, green light, blue light, yellow light, or ultraviolet light.

[0148] In some embodiments, see Figure 3 The driving substrate 1 further includes a common contact 100, wherein the common contact 100 may be a cathode metal contact, and the contact 101 may be an anode metal contact. The contact 101 is independently connected to each LED unit, applies an anode voltage, and provides a separate driving signal, so as to achieve the purpose of individually controlling the light emission of each LED unit.

[0149] In some embodiments, a method for preparing a micro light emitting diode display chip is provided, comprising:

[0150] Providing a driving substrate 1, and dividing the driving substrate 1 into at least a first light emitting area 200 and a second light emitting area 300, wherein the driving substrate 1 includes a plurality of contacts 101;

[0151] forming a first epitaxial layer 61 on the first light emitting region 200;

[0152] forming a second epitaxial layer 71 on the second light emitting region 300;

[0153] The first epitaxial layer 61 located in the first light-emitting region 200 is processed to form a first light-emitting module 2, wherein the first light-emitting module 2 includes a plurality of first LED units 21 arranged in an array, and the first LED units 21 are driven individually through corresponding contacts 101;

[0154] The second epitaxial layer 71 located in the second light-emitting region 300 is processed to form a second light-emitting module 3, which is located in the same plane as the first light-emitting module 2 and is spaced apart; the second light-emitting module 3 includes a plurality of second LED units 31 arranged in an array, and the second LED units 31 are driven individually through corresponding contacts 101;

[0155] All first LED units 21 in the first light-emitting module 2 emit light of the same color, all second LED units 31 in the second light-emitting module 3 emit light of the same color, and the color of the light emitted by the first LED unit 21 is different from the color of the light emitted by the second LED unit 31.

[0156] It can be understood that the preparation method of the present application sets a light-emitting module capable of emitting different light colors on the same plane of the driving substrate 1, thereby realizing a multi-color display of the chip and improving the compactness and space utilization of the chip.

[0157] In some embodiments, the driving substrate 1 is further separated into a third light emitting region 400, and after the second epitaxial layer 71 is formed on the second light emitting region 300, the driving substrate 1 further includes:

[0158] forming a third epitaxial layer 81 on the third light emitting region 400;

[0159] The third epitaxial layer 81 located in the third light-emitting region 400 is processed to form a third light-emitting module 4, which is spaced apart from the second light-emitting module 3 on a side away from the first light-emitting module 2, and is located in the same plane as the second light-emitting module 3 and the first light-emitting module 2; the third light-emitting module 4 includes a plurality of third LED units 41 arranged in an array, and the third LED units 41 are driven individually through corresponding contacts 101;

[0160] All the third LED units 41 in the third light-emitting module 4 emit light of the same color, and the color of the light emitted by the third LED unit 41 is different from the color of the light emitted by at least one of the first LED unit 21 and the second LED unit 31 .

[0161] In some embodiments, the step of forming the first epitaxial layer 61 on the first light emitting region 200 further includes:

[0162] See also Figure 4, providing a first substrate 6, and forming a first epitaxial layer 61 on the first substrate 6; the first substrate 6 may be a silicon substrate or a sapphire substrate, and the specific process of forming the first epitaxial layer 61 on the first substrate 6 is: depositing an n-type layer, an activation layer, and a p-type layer on the first substrate 6 respectively. These layers may be grown using methods such as metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy, and precise deposition and film thickness control may be achieved by controlling parameters such as temperature, flow rate, and reaction time.

[0163] See also Figure 3 , Figure 5 and Figure 6 The driving substrate 1 is a complementary metal oxide semiconductor CMOS device, and the CMOS device can form a driving circuit in the driving substrate 1. A bonding layer 5 is formed on the driving substrate 1 and the first epitaxial layer 61, and the driving substrate 1 and the first epitaxial layer 61 are bonded through the bonding layer 5 to form the first epitaxial layer 61 on the first light-emitting region 200 of the driving substrate 1, and the first substrate 6 is removed; through the fusion of the bonding layer 5, the first epitaxial layer 61 can be bonded to the driving substrate 1, and then the driving substrate 1 is peeled off to achieve the bonding of the driving substrate 1 and the driving substrate 1 through the bonding layer 5. The peeling method includes but is not limited to laser peeling, dry etching, wet etching, mechanical polishing, etc. The bonding layer 5 can be prepared by atomic layer deposition (ALD), chemical vapor deposition (CVD), evaporation, sputtering, etc. In some embodiments, it is also necessary to perform a thinning operation on the flipped first epitaxial layer 61, and the thinning operation includes dry etching, wet etching or mechanical polishing.

[0164] See also Figure 7 and Figure 8 , the first epitaxial layer 61 located in the second light emitting region 300 and the third light emitting region 400 is etched away, and the first epitaxial layer 61 located on the first light emitting region 200 is retained. The etching is a dry etching, wherein a mask layer 9 is provided on the first epitaxial layer 61 located on the first light emitting region 200, and then the first epitaxial layer 61 of the second light emitting region 300 and the third light emitting region 400 is removed by dry etching.

[0165] See also Fig. 9, providing a second substrate 7, and forming a second epitaxial layer 71 on the second substrate 7; the second substrate 7 may be a silicon substrate or a sapphire substrate, and the specific process of forming the second epitaxial layer 71 on the second substrate 7 is: depositing an n-type layer, an activation layer, and a p-type layer on the second substrate 7 respectively. These layers may be grown using methods such as metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy, and precise deposition and film thickness control may be achieved by controlling parameters such as temperature, flow rate, and reaction time.

[0166] See also Fig. 9 , a bonding layer 5 is formed on the second epitaxial layer 71. The bonding layer 5 can be prepared by atomic layer deposition (ALD), chemical vapor deposition (CVD), evaporation, sputtering, etc.

[0167] See also Fig.10 , the second epitaxial layer 71 corresponding to the first light emitting region 200 and the third light emitting region 400 is removed by etching, and the second epitaxial layer 71 corresponding to the second light emitting region 300 is retained. The etching method can be dry etching or wet etching.

[0168] See also Fig.11 and Fig.12 The driving substrate 1 and the second epitaxial layer 71 are bonded via the bonding layer 5 to form the second epitaxial layer 71 on the second light emitting region 300 of the driving substrate 1, and the second substrate 7 is removed. The bonding is formed in the same manner as the first epitaxial layer 61.

[0169] See also Fig.13 , providing a third substrate 8, and forming a third epitaxial layer 81 on the third substrate 8; the third substrate 8 may be a silicon substrate or a sapphire substrate, and the specific process of forming the third epitaxial layer 81 on the third substrate 8 is: depositing an n-type layer, an activation layer, and a p-type layer on the third substrate 8 respectively. These layers may be grown using methods such as metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy, and precise deposition and film thickness control may be achieved by controlling parameters such as temperature, flow rate, and reaction time.

[0170] See also Fig.13, a bonding layer 5 is formed on the third epitaxial layer 81; the bonding layer 5 can be prepared by atomic layer deposition (ALD), chemical vapor deposition (CVD), evaporation, sputtering, etc.

[0171] See also Fig.14 , the third epitaxial layer 81 corresponding to the first light emitting region 200 and the second light emitting region 300 is removed by etching, and the third epitaxial layer 81 corresponding to the third light emitting region 400 is retained.

[0172] See also Fig.15 and Fig.16 The driving substrate 1 and the third epitaxial layer 81 are bonded via the bonding layer 5 to form the third epitaxial layer 81 on the third light emitting region 400 of the driving substrate 1, and the third substrate 8 is removed. The bonding is formed in the same manner as the first epitaxial layer 61.

[0173] In some embodiments, the step of processing the first epitaxial layer 61 located in the first light emitting region 200 to form the first light emitting module 2 further includes:

[0174] See also Fig.17 and Figure 2 , the first epitaxial layer 61 is etched to form a plurality of first LED units 21, and the first LED units 21 are arranged in an array on the bonding layer 5; a first passivation layer 22 is formed on the side surfaces of the first LED units 21 and the bonding layer 5; a first electrode layer 23 is formed on a side of the first passivation layer 22 away from the first LED units 21, and the first electrode layer 23 is electrically connected to the corresponding contacts 101 and a portion of the top surface of the first LED units 22, respectively, and the first passivation layer 22 electrically isolates the first electrode layer 23 from any one of the first LED units 21 and the bonding layer 5.

[0175] In some embodiments, the step of processing the second epitaxial layer 71 located in the second light emitting region 300 to form the second light emitting module 3 further includes:

[0176] See also Fig.17 and Figure 2 , the second epitaxial layer 71 is etched to form a plurality of second LED units 31, and the second LED units 31 are arranged in an array on the bonding layer 5; a second passivation layer 32 is formed on the side of the second LED unit 31 and the side of the bonding layer 5; a second electrode layer 33 is formed on the side of the second passivation layer 32 away from the second LED unit 31, and the second electrode layer 33 is electrically connected to the corresponding contacts 101 and a portion of the top surface of the second LED unit 31, respectively, and the second passivation layer 32 electrically isolates the second electrode layer 33 from any one of the second LED unit 31 and the bonding layer 5.

[0177] In some embodiments, the step of processing the third epitaxial layer 81 located in the third light emitting region 400 to form the third light emitting module 3 further includes:

[0178] See also Fig.17 and Figure 2 , the third epitaxial layer 81 is etched to form a plurality of third LED units 41, and the third LED units 41 are arranged in an array on the bonding layer 5; a third passivation layer 42 is formed on the side of the third LED unit 41 and the side of the bonding layer 5; a third electrode layer 43 is formed on the side of the third passivation layer 42 away from the third LED unit 41, and the third electrode layer 43 is electrically connected to the corresponding contact 101 and a portion of the top surface of the third LED unit 41, respectively, and the third passivation layer 42 electrically isolates the third electrode layer 43 from any one of the third LED unit 41 and the bonding layer 5.

[0179] In some embodiments, a MESA pattern can be designed according to a patterned mask, and the first epitaxial layer 61, the second epitaxial layer 71 and the third epitaxial layer 81 can be etched to form a first LED unit 21, a second LED unit 31 and a third LED unit 41 with multiple step structures; the first passivation layer 22, the second passivation layer 32, and the third passivation layer 42 can be formed by deposition, sputtering, etc., and the passivation layer can be used to form a protective structure on the surface of the LED unit to prevent etched contaminants from being sputtered onto the surface of the LED unit during subsequent etching.

[0180] It should be noted that the embodiment of the present application does not specifically limit the sequence of steps in the method for preparing the micro light emitting diode display chip.

[0181] In the embodiments of the manufacturing method in the present application, only the manufacturing process or steps are described. The device structure, shape, material, etc. not described can refer to the above-mentioned embodiments of the micro light emitting diode display chip and will not be repeated here.

[0182] See also Fig.18 and Fig.19 A display device comprises the above-mentioned micro light emitting diode display chip; wherein, the light emitting direction of the first light emitting module 2 and the second light emitting module 3 is a first direction U, the direction in which the first light emitting module 2 and the second light emitting module 3 are spaced apart is a second direction V, and the first direction U intersects with the second direction V.

[0183] In some embodiments, the display device also includes: a first light combining module 20, the first light combining module 20 and the first light emitting module 2 are correspondingly arranged in the first direction U, and the first light combining module 20 is used to convert the light emitted by the first light emitting module 2 from the first direction U to the second direction V for emission; a second light combining module 30, the second light combining module 30 and the first light combining module 20 are spaced apart and located in the same plane in the second direction V; the second light combining module 30 and the second light emitting module 3 are correspondingly arranged in the first direction U, and the second light combining module 30 is used to convert the light emitted by the second light emitting module 3 from the first direction U to the second direction V for emission, and to allow the light emitted by the first light emitting module 2 to pass through.

[0184] In some embodiments, the display device also includes: a third light combining module 40, the third light combining module 40 is arranged at a distance along the second direction V on the side of the second light combining module 30 away from the first light combining module 20, and the third light combining module 40 is located in the same plane as the first light combining module 20 and the second light combining module 30; the third light combining module 40 and the third light emitting module 4 are arranged correspondingly in the first direction U, and the third light combining module 40 is used to convert the light emitted by the third light emitting module 4 from the first direction U to the second direction V, and to allow the light emitted by the first light emitting module 2 and the second light emitting module 3 to pass through.

[0185] It can be understood that the display device of this embodiment arranges light-emitting modules emitting light of different colors on the same driving substrate 1, so that the light output of the light-emitting modules is already aligned on the surface along the second direction V. It is only necessary to adjust the angle and the front-to-back distance of the first light-combining module 20 and the second light-combining module 30 to complete the light combination of multiple colors. Compared with the light-combining structure of multiple independent display chips through a prism, the alignment difficulty of this embodiment is greatly improved, and the structure of the light-combining module is simpler, and it has a wide range of application scenarios.

[0186] by Fig.18 For example, the display device is not only used for three-color light combination, the driving substrate 1 is not limited to three colors, and is not limited to three light-emitting modules.

[0187] Specifically, the combination of colors on the driving substrate 1 can be: the first light-emitting module 1, the second light-emitting module 2 and the third light-emitting module 3 all emit light of one color, such as red light, green light or blue light, to achieve brightening of monochromatic light; or the first light-emitting module 1 emits red light, the second light-emitting module 2 emits green light, and the third light-emitting module 3 emits blue light, to achieve a three-color full-color display; or, the number of light-emitting modules is greater than three, and three of the light-emitting modules emit red, green and blue light respectively, and one light-emitting module emits white light, to enhance the brightness of the three-color combined light by white light; or, the number of light-emitting modules is greater than three, and two of the light-emitting modules emit red light, one light-emitting module emits green light, and one light-emitting module emits blue light, and an additional light-emitting module that emits red light can make up for the problem of weak red light.

[0188] In some embodiments, see further Fig.18 and Fig.19 The first light-combining module 20 has a first optical film 201 facing the first light-emitting module 2; the orthographic projection of the first optical film 201 on the driving substrate 1 along the first direction U covers the first light-emitting module 2; the second light-combining module 30 has a second optical film 301 facing the second light-emitting module 3; the orthographic projection of the second optical film 301 on the driving substrate 1 along the first direction U covers the second light-emitting module 3; the third light-combining module 40 has a third optical film 401 facing the third light-emitting module 4; the orthographic projection of the third optical film 401 on the driving substrate 1 along the first direction U covers the third light-emitting module 4.

[0189] In some embodiments, the first optical film 201, the second optical film 301, and the third optical film 401 may be polarized beam splitting films, which are composite films of multilayer metal or semiconductor materials, and achieve polarization and spectral separation of light by utilizing the interference effect of the multilayer films.

[0190] In some embodiments, the first optical film 201 is inclined relative to the surface of the first light-emitting module 2; the second optical film 301 is inclined relative to the surface of the second light-emitting module 3; the third optical film 401 is inclined relative to the surface of the third light-emitting module 4; wherein the first light-emitting surface 201, the second optical film 301, and the third optical film 401 are arranged parallel to each other.

[0191] In some embodiments, the surfaces of the first light combining module 20, the second light combining module 30, and the third light combining module 40 may also be made of single-sided highly reflective transparent material, and the second light combining module 30 and the third light combining module 40 also need to be made of materials with high transmittance to facilitate the transmission of the first color light and the second color light. Specifically, the high transmittance material may include transparent glass, silicon nitride, etc.

[0192] 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.

[0193] The present invention has been introduced in detail above. Specific examples have been applied in the present invention 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 light emitting diode display chip, characterized in that: include: A driving substrate (1), the driving substrate (1) comprising a plurality of contacts (101); A first light-emitting module (2) is arranged on the driving substrate (1), the first light-emitting module (2) comprising a plurality of first LED units (21) arranged in an array; the first LED units (21) are driven individually via corresponding contacts; a second light-emitting module (3) disposed on the driving substrate (1) and spaced apart from the first light-emitting module (2); the second light-emitting module (3) and the first light-emitting module (2) are located on the same plane; the second light-emitting module (3) comprises a plurality of second LED units (31) arranged in an array; the second LED units (31) are driven individually via the corresponding contacts (101); All the first LED units (21) in the first light-emitting module (2) emit light of the same color, all the second LED units (31) in the second light-emitting module (3) emit light of the same color, and the color of the light emitted by the first LED unit (21) is different from the color of the light emitted by the second LED unit (31).

2. The micro light emitting diode display chip according to claim 1, characterized in that: Also includes: A third light-emitting module (4) is disposed on the driving substrate (1) and is spaced apart from the second light-emitting module (3) on a side away from the first light-emitting module (2); The third light-emitting module (4) and the second light-emitting module (3) and the first light-emitting module (2) are all located in the same plane; the third light-emitting module (4) comprises a plurality of third LED units (41) arranged in an array; the third LED units (41) are driven individually via the corresponding contacts (101); All third LED units (41) in the third light-emitting module (4) emit light of the same color, and the color of the light emitted by the third LED unit (41) is different from the color of the light emitted by at least one of the first LED unit (21) and the second LED unit (31).

3. The micro light emitting diode display chip according to claim 2, characterized in that: Also includes: A bonding layer (5) is provided on the driving substrate (1); any one of the first LED unit (21), the second LED unit (31), and the third LED unit (41) is electrically connected to the bonding layer (5).

4. The micro light emitting diode display chip according to claim 3, characterized in that: The first light-emitting module (2) further comprises: A first passivation layer (22), the first passivation layer (22) covering a side surface of the bonding layer (5) and a side surface of the first LED unit (21); a first electrode layer (23), the first electrode layer (23) covering a side of the first passivation layer (22) away from the first LED unit (21), and the first passivation layer (22) electrically isolating the first electrode layer (23) from any one of the first LED unit (21) and the bonding layer (5); the first electrode layer (23) is electrically connected to the corresponding contact point (101) and a portion of the top surface of the first LED unit (21); The second light-emitting module (3) further comprises: A second passivation layer (32), the second passivation layer (32) covering a side surface of the bonding layer (5) and a side surface of the second LED unit (31); a second electrode layer (33), the second electrode layer (33) covering a side of the second passivation layer (32) away from the second LED unit (31), and the second passivation layer (32) electrically isolates the second electrode layer (33) from any one of the second LED unit (31) and the bonding layer (5); the second electrode layer (33) is electrically connected to the corresponding contact point (101) and a portion of the top surface of the second LED unit (31); The third light-emitting module (4) further comprises: A third passivation layer (42), the third passivation layer (42) covering a side surface of the bonding layer (5) and a side surface of the third LED unit (41); A third electrode layer (43), the third electrode layer (43) covers a side of the third passivation layer (42) away from the third LED unit (41), and the third passivation layer (42) electrically isolates the third electrode layer (43) from any one of the third LED unit (41) and the bonding layer (5); the third electrode layer (43) is electrically connected to the corresponding contact (101) and a portion of the top surface of the third LED unit (41), respectively.

5. The micro light emitting diode display chip according to claim 2, characterized in that: The driving substrate (1) has a length direction (X); the first light-emitting module (2), the second light-emitting module (3), and the third light-emitting module (4) are arranged in sequence and spaced apart along the length direction (X); There is a minimum distance A between the first light-emitting module (2) and the second light-emitting module (3) along the length direction (X), and there is a minimum distance B between the second light-emitting module (3) and the third light-emitting module (4) along the length direction (X), satisfying: 0.1 micron ≤ A ≤ 10000 microns, and 0.1 micron ≤ B ≤ 10000 microns.

6. The micro light emitting diode display chip according to claim 5, characterized in that: The driving substrate (1) also has a width direction (Y) perpendicular to the length direction (X); In the first light-emitting module (2), a plurality of the first LED (21) units are arranged at intervals along the length direction (X) and the width direction (Y), adjacent first LED units (21) have a minimum distance a1 along the length direction (X), and adjacent first LED units (21) have a minimum distance a2 along the width direction (Y); In the second light-emitting module (3), a plurality of second LED units (31) are arranged at intervals along the length direction (X) and the width direction (Y), adjacent second LED units (31) have a minimum distance b1 along the length direction (X), and adjacent second LED units (31) have a minimum distance b2 along the width direction (Y); In the third light-emitting module (4), a plurality of the third LED units (41) are arranged at intervals along the length direction (X) and the width direction (Y), adjacent third LED units (41) have a minimum distance c1 along the length direction (X), and adjacent third LED units (42) have a minimum distance c2 along the width direction (Y); The micro light emitting diode display chip further satisfies at least one of the following characteristics: a) 0.1 micron ≤ a1 ≤ 100 microns; b) 0.1 micron ≤ a2 ≤ 100 microns; c) 0.1 micron ≤ b1 ≤ 100 microns; d) 0.1 micron ≤ b2 ≤ 100 microns; e) 0.1 micron ≤ c1 ≤ 100 microns; f)0.1 micron ≤ c2 ≤ 100 microns.

7. The micro light emitting diode display chip according to claim 3, characterized in that: At least one of the first LED unit (21), the second LED unit (31), and the third LED unit (41) is a step structure, wherein the step structure comprises a first doped semiconductor layer (102), a second doped semiconductor layer (103), and an active layer (104) located therebetween; the step structure disconnects and electrically isolates the adjacent second doped semiconductor layer (103), the active layer (104), and the first doped semiconductor layer (102); and the contact (101) is electrically connected to the corresponding first doped semiconductor layer (102).

8. The micro light emitting diode display chip according to claim 2, characterized in that: The size of any one of the first LED unit (21), the second LED unit (31), and the third LED unit (41) is 1 to 10 μm; or The driving substrate (1) is a silicon-based CMOS driving board or a thin film field effect transistor driving board.

9. A method for preparing a micro light emitting diode display chip, characterized in that: include: Providing a driving substrate (1), and dividing the driving substrate (1) into at least a first light-emitting area (200) and a second light-emitting area (300), wherein the driving substrate (1) comprises a plurality of contacts (101); forming a first epitaxial layer (61) on the first light emitting region (200); forming a second epitaxial layer (71) on the second light emitting region (300); Processing a first epitaxial layer (61) located in a first light-emitting region (200) to form a first light-emitting module (2), the first light-emitting module (2) comprising a plurality of first LED units (21) arranged in an array, the first LED units (21) being driven individually via corresponding contacts (101); The second epitaxial layer (71) located in the second light-emitting area (300) is processed to form a second light-emitting module (3), the second light-emitting module (3) and the first light-emitting module (2) being located in the same plane and spaced apart; the second light-emitting module (3) comprises a plurality of second LED units (31) arranged in an array, the second LED units (31) being driven individually via the corresponding contacts (101); All the first LED units (21) in the first light-emitting module (2) emit light of the same color, all the second LED units (31) in the second light-emitting module (3) emit light of the same color, and the color of the light emitted by the first LED unit (21) is different from the color of the light emitted by the second LED unit (31).

10. The method for preparing a micro light emitting diode display chip according to claim 9, characterized in that: The driving substrate (1) is further divided into a third light-emitting region (400), and after the second epitaxial layer (71) is formed on the second light-emitting region (300), it further comprises: forming a third epitaxial layer (81) on the third light emitting region (400); The third epitaxial layer (81) located in the third light-emitting region (400) is processed to form a third light-emitting module (4), the third light-emitting module (4) being spaced apart from the second light-emitting module (3) on a side away from the first light-emitting module (2), and being located in the same plane as the second light-emitting module (3) and the first light-emitting module (2); the third light-emitting module (4) comprising a plurality of third LED units (41) arranged in an array, the third LED units (41) being driven individually via the corresponding contacts (101); All third LED units (41) in the third light-emitting module (4) emit light of the same color, and the color of the light emitted by the third LED unit (41) is different from the color of the light emitted by at least one of the first LED unit (21) and the second LED unit (31).

11. The method for preparing a micro light emitting diode display chip according to claim 10, characterized in that: The step of forming the first epitaxial layer (61) on the first light emitting region (200) further comprises: Providing a first substrate (6), and forming a first epitaxial layer (61) on the first substrate (6); forming a bonding layer (5) on the driving substrate (1) and / or the first epitaxial layer (61), bonding the driving substrate (1) and the first epitaxial layer (61) via the bonding layer (5) to form a first epitaxial layer (61) on the first light-emitting region (200) of the driving substrate (1), and removing the first substrate (6); Etching and removing the first epitaxial layer (61) located in the second light-emitting region (300) and the third light-emitting region (400), and retaining the first epitaxial layer (61) located on the first light-emitting region (200); The step of forming the second epitaxial layer (71) on the second light emitting region (300) further comprises: Providing a second substrate (7), and forming a second epitaxial layer (71) on the second substrate (7); forming a bonding layer (5) on the second epitaxial layer (71); Etching and removing the second epitaxial layer (71) corresponding to the first light-emitting region (200) and the second epitaxial layer (71) corresponding to the third light-emitting region (400), and retaining the second epitaxial layer (71) corresponding to the second light-emitting region (300); Bonding the driving substrate (1) and the second epitaxial layer (71) via the bonding layer (5) to form a second epitaxial layer (71) on the second light-emitting region (300) of the driving substrate (1), and removing the second substrate (7); The step of forming the third epitaxial layer (81) on the third light emitting region (400) further comprises: Providing a third substrate (8), and forming a third epitaxial layer (81) on the third substrate (8); forming a bonding layer (5) on the third epitaxial layer (81); Etching and removing the third epitaxial layer (81) corresponding to the first light-emitting region (200) and the second light-emitting region (300), and retaining the third epitaxial layer (81) corresponding to the third light-emitting region (400); The driving substrate (1) and the third epitaxial layer (81) are bonded via the bonding layer (5) to form a third epitaxial layer (81) on the third light emitting region (400) of the driving substrate (1), and the third substrate (8) is removed.

12. The method for preparing a micro light emitting diode display chip according to claim 11, characterized in that: The step of processing the first epitaxial layer (61) located in the first light-emitting region (200) to form a first light-emitting module (2) further comprises: Etching the first epitaxial layer (61) to form a plurality of the first LED units (21), wherein the first LED units (21) are arranged in an array on the bonding layer (5); forming a first passivation layer (22) on the side surface of the first LED unit (21) and the side surface of the bonding layer (5); A first electrode layer (23) is formed on a side of the first passivation layer (22) away from the first LED unit (21); the first electrode layer (23) is electrically connected to the corresponding contact points (101) and a portion of the top surface of the first LED unit (22), respectively; the first passivation layer (22) electrically isolates the first electrode layer (23) from the first LED unit (21) and the bonding layer (5).

13. The method for preparing a micro light emitting diode display chip according to claim 11, characterized in that: The step of processing the second epitaxial layer (71) located in the second light-emitting region (300) to form a second light-emitting module (3) further comprises: Etching the second epitaxial layer (71) to form a plurality of second LED units (31), wherein the second LED units (31) are arranged in an array on the bonding layer (5); forming a second passivation layer (32) on the side surface of the second LED unit (31) and the side surface of the bonding layer (5); A second electrode layer (33) is formed on a side of the second passivation layer (32) away from the second LED unit (31); the second electrode layer (33) is electrically connected to the corresponding contact points (101) and a portion of the top surface of the second LED unit (31), respectively; the second passivation layer (32) electrically isolates the second electrode layer (33) from the second LED unit (31) and any one of the bonding layer (5).

14. The method for preparing a micro light emitting diode display chip according to claim 11, characterized in that: The step of processing the third epitaxial layer (81) located in the third light-emitting region (400) to form a third light-emitting module (3) further comprises: Etching the third epitaxial layer (81) to form a plurality of third LED units (41), wherein the third LED units (41) are arranged in an array on the bonding layer (5); forming a third passivation layer (42) on the side surface of the third LED unit (41) and the side surface of the bonding layer (5); A third electrode layer (43) is formed on a side of the third passivation layer (42) away from the third LED unit (41); the third electrode layer (43) is electrically connected to the corresponding contact points (101) and a portion of the top surface of the third LED unit (41), respectively; and the third passivation layer (42) electrically isolates the third electrode layer (43) from any one of the third LED unit (41) and the bonding layer (5).

15. A display device, characterized in that: A micro light emitting diode display chip comprising any one of claims 1-8; or a micro light emitting diode display chip prepared by the preparation method of any one of claims 11-14.

16. The display device according to claim 15, characterized in that: The light emitting direction of the first light emitting module (2) and / or the second light emitting module (3) is a first direction (U), the direction in which the first light emitting module (2) and the second light emitting module (3) are arranged at intervals is a second direction (V), and the first direction (U) intersects with the second direction (V); The display device further includes: a first light combining module (20), the first light combining module (20) being arranged corresponding to the first light emitting module (2) in the first direction (U), the first light combining module (20) being used for converting light emitted by the first light emitting module (2) from the first direction (U) to be emitted in a second direction (V); A second light combining module (30), wherein the second light combining module (30) and the first light combining module (20) are arranged at intervals in the second direction (V) and are located in the same plane; the second light combining module (30) and the second light emitting module (3) are arranged correspondingly in the first direction (U), and the second light combining module (30) is used to convert the light emitted by the second light emitting module (3) from the first direction (U) to the second direction (V), and to allow the light emitted by the first light emitting module (2) to pass through.

17. The display device according to claim 16, characterized in that: The display device further includes: A third light combining module (40), the third light combining module (40) being arranged at intervals along the second direction (V) on a side of the second light combining module (30) away from the first light combining module (20), the third light combining module (40) being located on the same plane as the first light combining module (20) and the second light combining module (30); the third light combining module (40) and the third light emitting module (4) being arranged correspondingly in the first direction (U), the third light combining module (40) being used for converting light emitted by the third light emitting module (4) from the first direction (U) to be emitted in the second direction (V), and allowing light emitted by the first light emitting module (2) and the second light emitting module (3) to be transmitted.

18. The display device according to claim 17, characterized in that: The first light combining module (20) has a first optical film (201) facing the first light emitting module (2); the orthographic projection of the first optical film (201) on the driving substrate (1) along the first direction (U) covers the first light emitting module (2); The second light combining module (30) has a second optical film (301) facing the second light emitting module (3); the orthographic projection of the second optical film (301) on the driving substrate (1) along the first direction (U) covers the second light emitting module (3); The third light combining module (40) has a third optical film (401) facing the third light emitting module (4); the orthographic projection of the third optical film (401) on the driving substrate (1) along the first direction (U) covers the third light emitting module (4).

19. The display device according to claim 18, characterized in that The first optical film (201) is inclined relative to the surface of the first light-emitting module (2); The second optical film (301) is inclined relative to the surface of the second light-emitting module (3); The third optical film (401) is inclined relative to the surface of the third light-emitting module (4); Wherein, the first light emitting surface (201), the second optical film (301), and the third optical film (401) are arranged parallel to each other.

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