Micro-led display chip and manufacturing method therefor

Abstract

The present application discloses a Micro-LED display chip and a manufacturing method therefor. The Micro-LED display chip comprises a driving panel, and a plurality of Micro-LED elements and a plurality of filter elements located on one side of the driving panel. Each Micro-LED element comprises at least two light emitting structure layers; the at least two light emitting structure layers are stacked in a direction perpendicular to the driving panel; and the at least two light emitting structure layers are connected in series, so that when the driving panel independently drives a Micro-LED element, the at least two light emitting structure layers in the Micro-LED element synchronously emit light. The plurality of filter elements and the plurality of Micro-LED elements are correspondingly arranged, and the filter elements are at least arranged above the light emitting surfaces of the corresponding Micro-LED elements. The technical solution of the present application can achieve color display without the need of using a wavelength conversion element to perform wavelength conversion, thereby improving the light emitting efficiency, light emitting brightness and life of the Micro-LED display chip.

Description

A Micro-LED display chip and its preparation method Technical Field

[0001] The present application relates to the field of micro-display technology, and in particular to a Micro-LED display chip and a method for preparing the same.

[0002] Background of the Invention

[0003] Micro-LED (Micro Light Emitting Diode) display chips are two-dimensional array display devices that integrate a high-density array of pixel light-emitting units on a single chip. Due to their advantages such as small size, long lifespan, fast response speed, and low power consumption, Micro-LED display chips are widely used in fields such as augmented reality (AR), near-eye display (NED), and wearable displays.

[0004] Although it is currently possible to achieve color display of Micro-LED display chips by using wavelength conversion elements to convert the excitation light emitted by Micro-LED elements into excited light of different wavelengths, the conversion efficiency and lifespan of the wavelength conversion elements will limit the luminous efficiency and lifespan of the Micro-LED display chips, resulting in the luminous efficiency and lifespan of the Micro-LED display chips being unable to be further improved. Summary of the Invention

[0005] This application discloses a Micro-LED display chip and a preparation method thereof, so as to improve the luminous efficiency and lifespan of the Micro-LED display chip.

[0006] In a first aspect, the present application discloses a Micro-LED display chip, comprising a driving panel and a plurality of Micro-LED elements and a plurality of filter elements located on one side of the driving panel; the plurality of Micro-LED elements are arranged at intervals, and each of the plurality of Micro-LED elements includes at least two light-emitting structure layers, the at least two light-emitting structure layers including a first light-emitting structure layer for emitting a first color light and a second light-emitting structure layer for emitting a second color light, the at least two light-emitting structure layers are stacked in a direction perpendicular to the driving panel, and the at least two light-emitting structure layers are connected in series so that when the driving panel drives the Micro-LED element alone, the at least two light-emitting structure layers in the Micro-LED element emit light synchronously; the plurality of filter elements are respectively arranged corresponding to the plurality of Micro-LED elements, and each of the plurality of filter elements is arranged at least above the light-emitting surface of the corresponding Micro-LED element, the plurality of filter elements include at least a first filter element and a second filter element, the first filter element is used to transmit the first color light and filter other color light except the first color light, and the second filter element is used to transmit the second color light and filter other color light except the second color light.

[0007] In some optional examples, the driving panel includes multiple first contacts and multiple second contacts, the multiple first contacts are respectively located between two adjacent Micro-LED elements among the multiple Micro-LED elements, and the multiple second contacts are respectively located under the multiple Micro-LED elements; in the Micro-LED element, any two adjacent light-emitting structure layers among at least two light-emitting structure layers are electrically connected; in the Micro-LED element, the light-emitting structure layer farthest from the driving panel is electrically connected to the corresponding first contact; in the Micro-LED element, the light-emitting structure layer closest to the driving panel is electrically connected to the corresponding second contact.

[0008] In some optional examples, each of the at least two light-emitting structure layers includes a first doped semiconductor layer, a light-emitting layer, and a second doped semiconductor layer that are stacked; in a Micro-LED element, in any two adjacent light-emitting structure layers of the at least two light-emitting structure layers, the first doped semiconductor layer of one light-emitting structure layer is electrically connected to the second doped semiconductor layer of another adjacent light-emitting structure layer to achieve series connection of the two adjacent light-emitting structure layers; in a Micro-LED element, the first doped semiconductor layer of the light-emitting structure layer farthest from the driving panel is electrically connected to the corresponding first contact, and the second doped semiconductor layer of the light-emitting structure layer closest to the driving panel is electrically connected to the corresponding second contact.

[0009] In some optional examples, the Micro-LED element further includes a bonding layer, and the bonding layer includes at least one first bonding layer and a second bonding layer; the first bonding layer is located between any two adjacent light-emitting structure layers among the at least two light-emitting structure layers, and the first bonding layer is used to bond and electrically connect the two adjacent light-emitting structure layers; the second bonding layer is located between the light-emitting structure layer closest to the driving panel and the driving panel, and the second bonding layer is used to bond the light-emitting structure layer closest to the driving panel to the driving panel and electrically connect to the second contact of the driving panel.

[0010] In some optional examples, the material of the first bonding layer includes a transparent conductive material to allow light emitted by at least two light-emitting structure layers to pass through, and the material of the second bonding layer includes a reflective conductive material to reflect light emitted by at least two light-emitting structure layers.

[0011] In some optional examples, the Micro-LED display chip further includes a passivation layer, which covers the light-emitting surface and side surfaces of the Micro-LED element; the passivation layer includes a plurality of first openings and a plurality of second openings; the plurality of first openings are used to respectively expose the first connection parts of the plurality of Micro-LED elements, and the first connection parts are the light-emitting structure layer in the Micro-LED element that is farthest from the driving panel; the plurality of second openings are used to respectively expose the plurality of first contacts of the driving panel.

[0012] In some optional examples, the Micro-LED display chip further includes a plurality of first electrodes; the plurality of first electrodes are respectively arranged corresponding to the plurality of Micro-LED elements, and each of the plurality of first electrodes electrically connects the first connection portion of the corresponding Micro-LED element to the corresponding first contact through the first opening and the second opening of the corresponding Micro-LED element.

[0013] In some optional examples, the Micro-LED display chip further includes an etch stop layer, which is located on the side of the passivation layer or the first electrode facing away from the driving panel, and covers the light emitting surface and side surfaces of the Micro-LED element.

[0014] In some optional examples, the Micro-LED display chip further includes a light-blocking wall, which is located between two adjacent Micro-LED elements among the multiple Micro-LED elements; the sidewall of the light-blocking wall has a reflective layer, which is used to reflect the output light of the Micro-LED element.

[0015] In some optional examples, a planarization layer is further provided between the filter element and the corresponding Micro-LED element, and the planarization layer allows light emitted by the Micro-LED element to pass through.

[0016] In some optional examples, the at least two light-emitting structure layers further include a third light-emitting structure layer that can emit a third color light, and the multiple filter elements further include a third filter element, which is used to transmit the third color light and filter other color lights except the third color light.

[0017] In some optional examples, the Micro-LED display chip further includes a plurality of microlenses, wherein the plurality of microlenses are respectively arranged corresponding to the plurality of Micro-LED elements, and each of the plurality of microlenses is used to gather and / or collimate the light emitted by the corresponding Micro-LED element.

[0018] In a second aspect, the present application discloses a method for preparing a Micro-LED display chip, comprising: forming at least two light-emitting structure layers stacked in a direction perpendicular to the driving panel on one side of a driving panel, and connecting the at least two light-emitting structure layers in series, the at least two light-emitting structure layers including a first light-emitting structure layer for emitting a first color light and a second light-emitting structure layer for emitting a second color light; etching the at least two light-emitting structure layers so that the at least two light-emitting structure layers form a plurality of Micro-LED elements arranged at intervals, and when the driving panel drives each of the plurality of Micro-LED elements individually, the at least two light-emitting structure layers in the Micro-LED elements emit light synchronously; forming a plurality of filter elements on one side of the driving panel, and arranging the plurality of filter elements to correspond to the plurality of Micro-LED elements respectively, and arranging each of the plurality of filter elements to be at least above the corresponding Micro-LED element, the plurality of filter elements including at least a first filter element and a second filter element, the first filter element being configured to transmit the first color light and filter light of other colors except the first color light, and the second filter element being configured to transmit the second color light and filter light of other colors except the second color light.

[0019] In some optional examples, forming at least two light-emitting structure layers stacked in a direction perpendicular to the driving panel on one side of the driving panel, and connecting the at least two light-emitting structure layers in series includes: setting a first light-emitting structure layer on a first substrate, the first light-emitting structure layer including a first doped semiconductor layer, a light-emitting layer, and a second doped semiconductor layer arranged in a stacked manner; setting a second light-emitting structure layer on a second substrate, the second light-emitting structure layer including a first doped semiconductor layer, a light-emitting layer, and a second doped semiconductor layer arranged in a stacked manner; bonding the first light-emitting structure layer to the driving panel through a second bonding layer, and electrically connecting the second doped semiconductor layer of the first light-emitting structure layer to the second contact corresponding to the driving panel; removing the first substrate and exposing the first doped semiconductor layer of the first light-emitting structure layer; bonding the first light-emitting structure layer to the second light-emitting structure layer through the first bonding layer, so that the first doped semiconductor layer of the first light-emitting structure layer is electrically connected to the second doped semiconductor layer of the second light-emitting structure layer, so as to realize the series connection of two adjacent light-emitting structure layers of at least two light-emitting structure layers; removing the second substrate and exposing the first doped semiconductor layer of the second light-emitting structure layer.

[0020] In some optional examples, the preparation method also includes: arranging a third light-emitting structure layer for emitting a third color of light on a third substrate, the third light-emitting structure layer including a first doped semiconductor layer, a light-emitting layer, and a second doped semiconductor layer arranged in a stacked manner; bonding the third light-emitting structure layer to the second light-emitting structure layer through a first bonding layer, and electrically connecting the first doped semiconductor layer of the second light-emitting structure layer to the second doped semiconductor layer of the third light-emitting structure layer to achieve series connection of two adjacent light-emitting structure layers of at least two light-emitting structure layers; removing the third substrate and exposing the first doped semiconductor layer of the third light-emitting structure layer; wherein the plurality of filter elements also include a third filter element, and the third filter element is used to transmit the third color of light and filter other color lights except the third color of light.

[0021] In some optional examples, after etching the at least two light-emitting structure layers so that the at least two light-emitting structure layers form a plurality of Micro-LED elements arranged at intervals, the preparation method further includes: forming a passivation layer covering the light-emitting surface and side surfaces of the Micro-LED element on one side of the driving panel, and providing the passivation layer with a plurality of first openings and a plurality of second openings; the plurality of first openings are used to respectively expose the first connection parts of the plurality of Micro-LED elements, and the first connection parts are the light-emitting structure layers in the Micro-LED element farthest from the driving panel; the plurality of second openings are used to respectively expose the plurality of first contacts of the driving panel; forming a plurality of first electrodes on one side of the driving panel, and providing the plurality of first electrodes corresponding to the plurality of Micro-LED elements, so that each of the plurality of first electrodes passes through the first opening and the second opening of the corresponding Micro-LED element, so that the first connection part of the corresponding Micro-LED element is electrically connected to the corresponding first contact.

[0022] In some optional examples, the preparation method further includes: forming an etch stop layer on one side of the driving panel, so that the etch stop layer is located on the side of the passivation layer or the first electrode away from the driving panel, and the etch stop layer covers the light emitting surface and side surfaces of the Micro-LED element.

[0023] In some optional examples, before forming a plurality of filter elements on one side of the driving panel, the preparation method further includes: forming a light-blocking wall on one side of the driving panel, and positioning the light-blocking wall between two adjacent Micro-LED elements among the plurality of Micro-LED elements; and forming a reflective layer on a side of the light-blocking wall facing the Micro-LED element, wherein the reflective layer is used to reflect the outgoing light of the Micro-LED element.

[0024] In some optional examples, the preparation method further includes: forming a planarization layer on one side of the driving panel, so that the planarization layer covers the Micro-LED element and fills the groove surrounded by the light-blocking wall, and the planarization layer allows light emitted by the Micro-LED element to pass through.

[0025] In some optional examples, the preparation method also includes: forming a plurality of microlenses on one side of the driving panel, the plurality of microlenses being respectively arranged corresponding to the plurality of Micro-LED elements, and each of the plurality of microlenses being used to gather and / or collimate the light emitted by the corresponding Micro-LED element.

[0026] The Micro-LED display chip and its preparation method disclosed in the present application include a driving panel and multiple Micro-LED elements and multiple filter elements located on one side of the driving panel. The multiple Micro-LED elements are arranged at intervals, and each Micro-LED element includes at least two light-emitting structure layers. The at least two light-emitting structure layers are stacked in a direction perpendicular to the driving panel, and the at least two light-emitting structure layers are connected in series so that when the driving panel drives the Micro-LED element alone, the at least two light-emitting structure layers in the Micro-LED element emit light synchronously. The multiple filter elements are respectively arranged corresponding to the multiple Micro-LED elements, and the filter elements are at least arranged above the light-emitting surface of the corresponding Micro-LED elements. The at least two light-emitting structure layers include at least a first light-emitting structure layer that can emit a first color of light and a second light-emitting structure layer that can emit a second color of light. The multiple filter elements include at least a first filter element and a second filter element. The first filter element is used to transmit the first color of light and filter other colors of light, and the second filter element is used to transmit the second color of light and filter other colors of light. Based on this, at least the first light-emitting structure layer and the second light-emitting structure layer connected in series can be used to emit the first color light and the second color light respectively, and at least the first filter element and the second filter element can be used to transmit the first color light and the second color light respectively for color display, so there is no need to use a wavelength conversion element for wavelength conversion, thereby improving the luminous efficiency, luminous brightness and lifespan of the Micro-LED display chip.

[0027] BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0029] FIG1 is a schematic diagram of the cross-sectional structure of a current Micro-LED display chip.

[0030] FIG2 is a schematic diagram of the cross-sectional structure of a Micro-LED display chip disclosed in an embodiment of the present application.

[0031] FIG3 is a schematic diagram of the cross-sectional structure of a Micro-LED element disclosed in an embodiment of the present application.

[0032] FIG4 is a schematic diagram of the cross-sectional structure of another Micro-LED element disclosed in an embodiment of the present application.

[0033] FIG5 is a schematic diagram of a cross-sectional structure of a portion of a Micro-LED element in the Micro-LED display chip shown in FIG2 .

[0034] FIG6 is a schematic diagram of another partial cross-sectional structure of the Micro-LED element in the Micro-LED display chip shown in FIG2 .

[0035] FIG7 is a schematic diagram of the cross-sectional structure of another Micro-LED element disclosed in an embodiment of the present application.

[0036] FIG8 is a schematic flow chart of a method for preparing a Micro-LED display chip disclosed in an embodiment of the present application.

[0037] 9 to 23 are schematic cross-sectional views of various steps in a method for manufacturing a Micro-LED display chip disclosed in an embodiment of the present application.

[0038] Modes for Carrying Out the Invention

[0039] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0040] A micro-LED display chip includes a micro-LED array, which is a high-density integrated array of LEDs with a pitch of microns. Each micro-LED element in the micro-LED array acts as a pixel and can be independently addressed and illuminated to display the corresponding image.

[0041] However, most current Micro-LED display chips use wavelength conversion elements to convert the excitation light emitted by the Micro-LED components into different wavelengths to achieve color display. As shown in Figure 1, the blue light emitted by Micro-LED component 01 excites the red wavelength conversion element 02 to produce red light, and the green wavelength conversion element 02 to produce green light. This mixed light of red, green, and blue light is then used to create a color display. However, due to the low conversion efficiency and lifespan of wavelength conversion element 02, the luminous efficiency and lifespan of the Micro-LED display chip are also reduced.

[0042] Based on this, the present application provides a display solution, which forms at least two light-emitting structure layers stacked and connected in series in a Micro-LED element, so that the at least two light-emitting structure layers respectively emit at least two colors of light, and transmit at least two colors of light respectively through at least two filter elements to perform color display, thereby improving the luminous efficiency and lifespan of the Micro-LED display chip.

[0043] As an optional implementation of the contents disclosed in this application, an embodiment of this application discloses a Micro-LED display chip. As shown in FIG2 , the Micro-LED display chip includes a driving panel 10 and a plurality of Micro-LED elements 11 and a plurality of filter elements 12 located on one side of the driving panel 10 .

[0044] In particular, multiple Micro-LED elements 11 are spaced apart, and each Micro-LED element 11 includes at least two light-emitting structure layers, each of which can emit at least two colors of light. In some embodiments of the present application, as shown in FIG2 , the Micro-LED element 11 includes a first light-emitting structure layer 111, a second light-emitting structure layer 112, and a third light-emitting structure layer 113. The first light-emitting structure layer 111 can emit a first color of light, the second light-emitting structure layer 112 can emit a second color of light, and the third light-emitting structure layer 113 can emit a third color of light. The first color of light, the second color of light, and the third color of light are green, red, and blue, respectively.

[0045] At least two light-emitting structure layers are stacked in a direction perpendicular to the driving panel 10 so that at least two colors of light are synthesized into mixed light and emitted. In some embodiments of the present application, as shown in FIG2 , the first light-emitting structure layer 111 , the second light-emitting structure layer 112 , and the third light-emitting structure layer 113 are stacked in a direction perpendicular to the driving panel 10 so that the green light, red light, and blue light emitted by them are synthesized into mixed light and emitted.

[0046] At least two light-emitting structure layers are connected in series so that when the driving panel 10 drives the Micro-LED element 11 alone, the at least two light-emitting structure layers within the Micro-LED element 11 emit light synchronously. In some embodiments of the present application, as shown in FIG2 , the first light-emitting structure layer 111, the second light-emitting structure layer 112, and the third light-emitting structure layer 113 are sequentially connected in series so that when the driving panel 10 drives the Micro-LED element 11 alone, the first light-emitting structure layer 111, the second light-emitting structure layer 112, and the third light-emitting structure layer 113 within the Micro-LED element 11 emit light synchronously.

[0047] Multiple filter elements 12 are respectively arranged corresponding to the multiple Micro-LED elements 11, and the filter elements 12 are at least arranged above the light-emitting surface of the corresponding Micro-LED element 11. The light-emitting surface of the Micro-LED element 11 is the surface of the side of the Micro-LED element 11 facing away from the driving panel 10. The multiple filter elements 12 include at least two filter elements, each filter element 12 can transmit one color of the mixed light emitted by the corresponding Micro-LED element 11 and filter other colors of light. At least two filter elements can respectively transmit at least two colors of light and filter other colors of light. The material of the filter element 12 includes an organic filter material, or the filter element 12 includes an inorganic Bragg reflector, etc.

[0048] In some embodiments of the present application, as shown in FIG2 , the filter element 12 includes a first filter element 121, a second filter element 122, and a third filter element 123. The first filter element 121 can transmit a first color of mixed light emitted by the corresponding Micro-LED element 11 and filter out other colors of light. The second filter element 122 can transmit a second color of mixed light emitted by the corresponding Micro-LED element 11 and filter out other colors of light. The third filter element 123 can transmit a third color of mixed light emitted by the corresponding Micro-LED element 11 and filter out other colors of light. The first, second, and third colors of light transmitted by the filter element 12 are green, red, and blue, respectively, so that the green, red, and blue lights transmitted by the filter element 12 can be displayed in full color.

[0049] In some embodiments of the present application, the examples in which the Micro-LED element 11 includes three light-emitting structure layers and the filter element 12 includes three color filter elements are used for illustration. However, the present invention is not limited to this example. In other embodiments, the Micro-LED element 11 may include two, four, or even more light-emitting structure layers. For example, the Micro-LED element 11 may include a first light-emitting structure layer that emits a first color of light and a second light-emitting structure layer that emits a second color of light. In other embodiments, the filter element 12 may include two, four, or even more color filter elements. For example, the filter element 12 may include a first filter element that transmits the first color of light and filters other colors of light, and a second filter element that transmits the second color of light and filters other colors of light. These details are not further described here.

[0050] Because the Micro-LED element 11 includes at least two light-emitting structural layers, the at least two colors of light emitted by the at least two light-emitting structural layers can be synthesized into a mixed light. Furthermore, the at least two light filters 12 can transmit at least two colors of the mixed light emitted by the corresponding Micro-LED element 11 and filter out the other colors. Therefore, the at least two colors of light transmitted by the at least two light filters 12 can be used for color display, eliminating the need for wavelength conversion elements. This can improve the luminous efficiency, brightness, and lifespan of the Micro-LED display chip. Furthermore, because the at least two light-emitting structural layers are stacked and connected in series, the driver design and manufacturing process of the Micro-LED element 11 can be simplified.

[0051] In some embodiments of the present application, to improve the light extraction efficiency of the Micro-LED element 11, the arrangement order of the at least two light-emitting structure layers within the same Micro-LED element 11 is restricted. For example, the at least two light-emitting structure layers are arranged from bottom to top in descending order of transmittance of the emitted color light. In some embodiments, the first light-emitting structure layer 111 emits red light as a first color, the second light-emitting structure layer 112 emits green light as a second color, and the third light-emitting structure layer 113 emits blue light as a third color.

[0052] In some embodiments of the present application, in order to achieve the series connection of at least two light-emitting structure layers, any two adjacent light-emitting structure layers in the same Micro-LED element 11 are electrically connected, the light-emitting structure layer farthest from the driving panel in any Micro-LED element 11 is electrically connected to the first contact 101 of the driving panel 10, and the light-emitting structure layer closest to the driving panel 10 in any Micro-LED element 11 is electrically connected to the second contact 102 of the driving panel 10.

[0053] In some embodiments, as shown in Figure 2, the first light-emitting structure layer 111 is electrically connected to the second light-emitting structure layer 112, the second light-emitting structure layer 112 is electrically connected to the third light-emitting structure layer 113, the third light-emitting structure layer 113 is electrically connected to the first contact 101 of the driving panel 10, and the first light-emitting structure layer 111 is electrically connected to the second contact 102 of the driving panel 10.

[0054] It should be noted that the driving panel 10 includes a substrate, multiple driving circuits located on one side of the substrate, and multiple first contacts 101 and multiple second contacts 102 electrically connected to the multiple driving circuits. The first contacts 101 are located between adjacent Micro-LED elements 11, and the second contacts 102 are located below the corresponding Micro-LED element 11. Each driving circuit includes a complementary metal oxide semiconductor (CMOS) device or a thin film transistor (TFT) device, and is electrically connected to a first contact 101 and a second contact 102. Each driving circuit provides a first voltage to the corresponding Micro-LED element 11 through the first contact 101 and provides a second voltage to the corresponding Micro-LED element 11 through the second contact 102, so that the Micro-LED element 11 is driven by the first voltage and the second voltage having a voltage difference.

[0055] In some embodiments, the light-emitting structure layer includes a stacked first doped semiconductor layer, a light-emitting layer, and a second doped semiconductor layer. As shown in FIG3 , the first light-emitting structure layer 111 includes a stacked first first doped semiconductor layer 111a, a first light-emitting layer 111b, and a first second doped semiconductor layer 111c. The second light-emitting structure layer 112 includes a stacked second first doped semiconductor layer 112a, a second light-emitting layer 112b, and a second second doped semiconductor layer 112c. The third light-emitting structure layer 113 includes a stacked third first doped semiconductor layer 113a, a third light-emitting layer 113b, and a third second doped semiconductor layer 113c. The light-emitting layers in the first light-emitting structure layer 111, the second light-emitting structure layer 112, and the third light-emitting structure layer 113 have different colors, so that the first light-emitting structure layer 111, the second light-emitting structure layer 112, and the third light-emitting structure layer 113 emit light of different colors.

[0056] Furthermore, in any two adjacent light-emitting structure layers within the same Micro-LED element 11, the first doped semiconductor layer of one light-emitting structure layer is adjacent to and electrically connected to the second doped semiconductor layer of the other light-emitting structure layer, so that any two adjacent light-emitting structure layers within the same Micro-LED element 11 are electrically connected. In some embodiments, the first doped semiconductor layer, the light-emitting layer, and the second doped semiconductor layer in the light-emitting structure layer can be stacked sequentially in a direction away from or close to the driving panel 10. When the first doped semiconductor layer, the light-emitting layer, and the second doped semiconductor layer are stacked sequentially in a direction close to the driving panel 10, the first doped semiconductor layer of the light-emitting structure layer farthest from the driving panel in any Micro-LED element 11 is electrically connected to the first contact 101 of the driving panel 10, so that the light-emitting structure layer farthest from the driving panel in any Micro-LED element 11 is electrically connected to the first contact 101 of the driving panel 10. The second doped semiconductor layer of the light emitting structure layer closest to the driving panel 10 in any Micro-LED element 11 is electrically connected to the second contact 102 of the driving panel 10, so that the light emitting structure layer closest to the driving panel 10 in any Micro-LED element 11 is electrically connected to the second contact 102 of the driving panel 10. The first doped semiconductor layer and the second doped semiconductor layer are oppositely doped semiconductor layers, that is, if the first doped semiconductor layer is an N-type semiconductor layer, the second doped semiconductor layer is a P-type semiconductor layer, or if the first doped semiconductor layer is a P-type semiconductor layer, the second doped semiconductor layer is an N-type semiconductor layer.

[0057] Optionally, in some embodiments, as shown in Figure 3, when the first doped semiconductor layer, the light-emitting layer and the second doped semiconductor layer are stacked in sequence along a direction away from the driving panel 10, the first second doped semiconductor layer 111c of the first light-emitting structure layer 111 is adjacent to and electrically connected to the second first doped semiconductor layer 112a of the second light-emitting structure layer 112, the second second doped semiconductor layer 112c of the second light-emitting structure layer 112 is electrically connected to the third first doped semiconductor layer 113a of the third light-emitting structure layer 113, the third second doped semiconductor layer 113c of the third light-emitting structure layer 113 is electrically connected to the first contact 101 of the driving panel 10, and the first first doped semiconductor layer 111a of the first light-emitting structure layer 111 is electrically connected to the second contact 102 of the driving panel 10.

[0058] Of course, the present application is not limited to this. In other embodiments, the light-emitting structure layer includes a stacked first electrode layer, a first doped semiconductor layer, a light-emitting layer, a second doped semiconductor layer, and a second electrode layer. As shown in FIG4 , the first light-emitting structure layer 111 includes a stacked first electrode layer 111d, a first first doped semiconductor layer 111a, a first light-emitting layer 111b, a first second doped semiconductor layer 111c, and a first second electrode layer 111e. The second light-emitting structure layer 112 includes a stacked second first electrode layer 112d, a second first doped semiconductor layer 112a, a second light-emitting layer 112b, a second second doped semiconductor layer 112c, and a second second electrode layer 112e. The third light-emitting structure layer 113 includes a stacked third first electrode layer 113d, a third first doped semiconductor layer 113a, a third light-emitting layer 113b, a third second doped semiconductor layer 113c, and a third second electrode layer 113e.

[0059] In any two adjacent light-emitting structure layers within the same Micro-LED element 11, the first electrode layer of one light-emitting structure layer is adjacent to and electrically connected to the second electrode layer of the other light-emitting structure layer, so that any two adjacent light-emitting structure layers within the same Micro-LED element 11 are electrically connected. In some embodiments, the first electrode layer, the first doped semiconductor layer, the light-emitting layer, the second doped semiconductor layer, and the second electrode layer in the light-emitting structure layer can be stacked sequentially in a direction away from or close to the driving panel 10. When the first electrode layer, the first doped semiconductor layer, the light-emitting layer, the second doped semiconductor layer, and the second electrode layer are stacked sequentially in a direction close to the driving panel 10, the first electrode layer of the light-emitting structure layer farthest from the driving panel 10 in any Micro-LED element 11 is electrically connected to the first contact 101 of the driving panel 10, so that the light-emitting structure layer farthest from the driving panel in any Micro-LED element 11 is electrically connected to the first contact 101 of the driving panel 10. The second electrode layer of the light-emitting structure layer closest to the driving panel 10 in any Micro-LED element 11 is electrically connected to the second contact 102 of the driving panel 10, so that the light-emitting structure layer closest to the driving panel 10 in any Micro-LED element 11 is electrically connected to the second contact 102 of the driving panel 10.

[0060] Optionally, in some embodiments, as shown in Figure 4, when the first electrode layer, the first doped semiconductor layer, the light-emitting layer, the second doped semiconductor layer and the second electrode layer are stacked in sequence in a direction away from the driving panel 10, the first second electrode layer 111e of the first light-emitting structure layer 111 is adjacent to and electrically connected to the second first electrode layer 112d of the second light-emitting structure layer 112, the second second electrode layer 112e of the second light-emitting structure layer 112 is electrically connected to the third first electrode layer 113d of the third light-emitting structure layer 113, the third second electrode layer 113e of the third light-emitting structure layer 113 is electrically connected to the first contact 101 of the driving panel 10, and the first first electrode layer 111d of the first light-emitting structure layer 111 is electrically connected to the second contact 102 of the driving panel 10.

[0061] In some embodiments of the present application, as shown in Figures 2 and 3, the Micro-LED element 11 further includes a bonding layer, which includes at least one first bonding layer 114 and a second bonding layer 115. The first bonding layer 114 is located between any two adjacent light-emitting structure layers, and the first bonding layer 114 can bond and electrically connect the adjacent light-emitting structure layers. The second bonding layer 115 is located between the light-emitting structure layer closest to the driving panel 10 and the driving panel 10, and the second bonding layer 115 can bond the light-emitting structure layer closest to the driving panel 10 to the driving panel 10 and electrically connect to the second contact 102 of the driving panel 10.

[0062] In some embodiments, as shown in Figures 2 and 3, a first bonding layer 114 is located between the first light-emitting structure layer 111 and the second light-emitting structure layer 112. This first bonding layer 114 can bond and electrically connect the first light-emitting structure layer 111 to the second light-emitting structure layer 112. Another first bonding layer 114 is located between the second light-emitting structure layer 112 and the third light-emitting structure layer 113. This first bonding layer 114 can bond and electrically connect the second light-emitting structure layer 112 to the third light-emitting structure layer 113. In this way, the first doped semiconductor layer of one light-emitting structure layer is adjacent to and electrically connected to the second doped semiconductor layer of another light-emitting structure layer. A second bonding layer 115 is located between the first light-emitting structure layer 111 and the driving panel 10. The second bonding layer 115 can bond the first light-emitting structure layer 111 to the driving panel 10 and electrically connect to the second contact 102 of the driving panel 10. In this embodiment, the bonding layer can be a structure comprising multiple material layers, including a material layer that serves as an electrode layer for the light-emitting structure layer and a material layer that performs a bonding and conductive function. In other embodiments, as shown in Figure 4, the electrode layer of the light emitting structure layer is designed separately, and the bonding layer is used to bond and electrically connect the electrode layers of adjacent light emitting structure layers. Of course, the present application is not limited to this.

[0063] In some embodiments of the present application, to improve the light extraction efficiency of the Micro-LED element 11, the material of the first bonding layer 114 includes a transparent metal oxide material or a combination thereof, such as ITO or IZO, and the material of the second bonding layer 115 includes a metal material or a combination thereof with high reflectivity, such as Al, Ag, Au, Cu, Sn, etc., to prevent light from being emitted from the side of the driving panel 10. In other embodiments, the materials of the first electrode layer and the second electrode layer include a transparent metal oxide material, and the material of the electrode layer between the light-emitting structure layer and the driving panel 10 is a metal material with high reflectivity.

[0064] In some embodiments of the present application, as shown in FIG5 , the Micro-LED display chip 11 further includes a passivation layer 116, which covers the light-emitting surface and side surfaces of the Micro-LED element 11. Furthermore, the passivation layer 116 includes a plurality of first openings 1161 and a plurality of second openings 1162. The plurality of first openings 1161 can respectively expose the first connection portions of the plurality of Micro-LED elements 11. The first connection portion is the portion of the light-emitting structure layer of the Micro-LED element 11 that is farthest from the driving panel 10 and can be electrically connected to the first contact 101 of the driving panel 10. The plurality of second openings 1162 can respectively expose the plurality of first contacts 101 of the driving panel 10.

[0065] In some embodiments of the present application, as shown in FIG6 , the Micro-LED display chip 11 further includes a plurality of first electrodes 117 . The plurality of first electrodes 117 are respectively disposed corresponding to the plurality of Micro-LED elements 11 . The first electrodes 117 are located on the side of the passivation layer 116 covering the corresponding Micro-LED element 11 that faces away from the driving panel 10 . The first electrodes 117 fill the first openings 1161 and the second openings 1162 adjacent to the corresponding Micro-LED element 11 . The first electrodes 117 can electrically connect the first connection portion of the corresponding Micro-LED element 11 to the corresponding first contact 101 . The passivation layer 116 can insulate the first electrodes 117 from the portion of the Micro-LED element 11 other than the first connection portion.

[0066] In some embodiments of the present application, as shown in FIG6 , the Micro-LED display chip further includes an etch stop layer 118. The etch stop layer 118 is located on the side of the passivation layer 116 or the first electrode 117 facing away from the driving panel 10. The etch stop layer 118 covers the light-emitting surface and side surfaces of the Micro-LED elements 11, as well as the driving panel 10 between the Micro-LED elements 11. The etch stop layer 118 protects the Micro-LED elements 11 from being damaged by etching in subsequent processes.

[0067] In some embodiments of the present application, as shown in FIG2 , a planarization layer 13 is provided between the filter element 12 and the corresponding Micro-LED element 11. Planarization layer 13 is configured to allow light emitted by Micro-LED element 11 to pass through. Planarization layer 13 may be made of a transparent adhesive or a transparent inorganic material to maximize transmission of light emitted by Micro-LED element 11. The transparent inorganic material may be silicon dioxide or aluminum oxide.

[0068] In some embodiments of the present application, as shown in FIG2 , the Micro-LED display chip further includes a light-blocking wall 14 located between adjacent Micro-LED elements 11 and their corresponding filter elements 12 to prevent light crosstalk between adjacent Micro-LED elements 11. The light-blocking wall 14 can be made of a black light-shielding material, a plastic material of any color, or an inorganic material.

[0069] Furthermore, the side of the light-blocking wall 14 facing the Micro-LED element 11 includes a reflective layer 15. This layer 15 reflects light emitted from the Micro-LED element 11, directing more of the light toward its light-emitting surface, thereby improving the light extraction efficiency and brightness of the Micro-LED element 11. The reflective layer 15 can be made of a metal or a combination thereof, such as Al, Ag, Au, Cu, or Sn. Furthermore, the reflective layer 15 can also be made of an organic reflective material.

[0070] In some embodiments of the present application, as shown in FIG7 , the Micro-LED display chip further includes a plurality of microlenses 17. The plurality of microlenses 17 are respectively disposed in correspondence with the plurality of Micro-LED elements 11. The microlenses 17 are used to focus and / or collimate the light emitted by the corresponding Micro-LED elements 11. It should be noted that the present embodiment is described only as an example in which the microlenses 17 are disposed on the side of the filter element 12 facing away from the driver panel 10. However, the present application is not limited to this embodiment. In other embodiments, the microlenses 17 may also be disposed between the filter element 12 and the Micro-LED element 11, which will not be further described here.

[0071] As an optional implementation of the disclosure of this application, an embodiment of this application discloses a method for preparing a Micro-LED display chip, as shown in FIG8 , comprising:

[0072] S101: Provide a driver panel.

[0073] As shown in FIG9 , the driving panel 10 includes a substrate, a plurality of driving circuits located on one side of the substrate, and a plurality of first contacts 101 and a plurality of second contacts 102 electrically connected to the plurality of driving circuits. Each driving circuit includes a CMOS device or a TFT device, and is electrically connected to one first contact 101 and one second contact 102.

[0074] S102: forming at least two light emitting structure layers stacked in a direction perpendicular to the driving panel on one side of the driving panel, and connecting the at least two light emitting structure layers in series.

[0075] The at least two light-emitting structural layers can each emit at least two colors of light. The at least two light-emitting structural layers are stacked perpendicular to the driving panel, allowing the at least two colors of light to be synthesized and emitted as mixed light. The at least two light-emitting structural layers are connected in series, allowing the at least two light-emitting structural layers within the Micro-LED element to emit light synchronously when the driving panel 10 alone drives the Micro-LED element.

[0076] In some embodiments of the present application, at least two light-emitting structure layers can be formed on the driving panel 10 by bonding. Taking the at least two light-emitting structure layers including a first light-emitting structure layer, a second light-emitting structure layer, and a third light-emitting structure layer as an example, first, a first substrate, a second substrate, and a third substrate are provided. The first light-emitting structure layer is disposed on the first substrate, the second light-emitting structure layer is disposed on the second substrate, and the third light-emitting structure layer is disposed on the third substrate. The first light-emitting structure layer, the second light-emitting structure layer, and the third light-emitting structure layer all include a first doped semiconductor layer, a light-emitting layer, and a second doped semiconductor layer that are stacked. Then, as shown in FIG10 , the first light emitting structure layer 111 is bonded to the driving panel 10 through the second bonding layer 115, and the second doped semiconductor layer of the first light emitting structure layer 111 is electrically connected to the second contact 102 corresponding to the driving panel 10, the first substrate 21 is removed and the first doped semiconductor layer of the first light emitting structure layer 111 is exposed, and then, as shown in FIG11 , the first light emitting structure layer 111 is bonded to the second light emitting structure 112 through a first bonding layer 114, so that the first doped semiconductor layer of the first light emitting structure layer 111 and the second doped semiconductor layer of the second light emitting structure layer 112 are electrically connected. The conductor layers are electrically connected to achieve a series connection between adjacent light-emitting structure layers. The second substrate 22 is removed to expose the first doped semiconductor layer of the second light-emitting structure layer 112. Then, as shown in FIG12 , the third light-emitting structure layer 113 is bonded to the second light-emitting structure layer 112 via another first bonding layer 114. The first doped semiconductor layer of the second light-emitting structure layer 112 is electrically connected to the second doped semiconductor layer of the third light-emitting structure layer 113 to achieve a series connection between adjacent light-emitting structure layers. The third substrate 23 is removed to expose the first doped semiconductor layer of the third light-emitting structure layer 113, forming the structure shown in FIG13 . Of course, the present application is not limited to this. In other embodiments, at least two light-emitting structure layers may also be formed directly on the driving panel 10, which will not be described in detail here.

[0077] In other embodiments, taking at least two light-emitting structure layers including a first light-emitting structure layer and a second light-emitting structure layer as an example, first, a first substrate and a second substrate are provided, the first light-emitting structure layer is disposed on the first substrate, and the second light-emitting structure layer is disposed on the second substrate, and the first light-emitting structure layer and the second light-emitting structure layer both include a first doped semiconductor layer, a light-emitting layer, and a second doped semiconductor layer that are stacked. Then, the first light-emitting structure layer is bonded to a driving panel via a second bonding layer, and the second doped semiconductor layer of the first light-emitting structure layer is electrically connected to a second contact corresponding to the driving panel. The first substrate is removed to expose the first doped semiconductor layer of the first light-emitting structure layer, and the first light-emitting structure layer and the second light-emitting structure layer are bonded to each other via the first bonding layer, so that the first doped semiconductor layer of the first light-emitting structure layer is electrically connected to the second doped semiconductor layer of the second light-emitting structure layer, thereby achieving series connection of adjacent light-emitting structure layers. The second substrate is removed to expose the first doped semiconductor layer of the second light-emitting structure layer.

[0078] In some embodiments of the present application, connecting at least two light-emitting structure layers in series includes: making the first doped semiconductor layer of one light-emitting structure layer adjacent to and electrically connected to the second doped semiconductor layer of the other light-emitting structure layer in any two adjacent light-emitting structure layers in the same Micro-LED element 11; and making the second doped semiconductor layer of the light-emitting structure layer closest to the driving panel 10 in any Micro-LED element 11 electrically connected to the second contact 102 of the driving panel 10.

[0079] Of course, the present application is not limited to this. In other embodiments, connecting at least two light-emitting structure layers in series includes: making the first electrode layer of one light-emitting structure layer adjacent to and electrically connected to the second electrode layer of the other light-emitting structure layer in any two adjacent light-emitting structure layers in the same Micro-LED element 11; and making the second electrode layer of the light-emitting structure layer closest to the driving panel 10 in any Micro-LED element 11 electrically connected to the second contact 102 of the driving panel 10.

[0080] In some embodiments of the present application, electrically connecting any two adjacent light-emitting structure layers within the same Micro-LED element 11 includes: forming a first bonding layer 114 between any two adjacent light-emitting structure layers, so that the adjacent light-emitting structure layers are bonded and electrically connected via the first bonding layer 114. Electrically connecting the light-emitting structure layer closest to the driving panel 10 within any Micro-LED element 11 to the second contact 102 of the driving panel 10 includes: forming a second bonding layer 115 between the light-emitting structure layer closest to the driving panel 10 within any Micro-LED element 11 and the driving panel 10, so that the light-emitting structure layer closest to the driving panel 10 is bonded and electrically connected to the second contact 102 of the driving panel 10 via the second bonding layer 115. Of course, the present application is not limited to this. In other embodiments, referring to FIG. 4 , adjacent light-emitting structure layers may also be electrically connected via electrode bonding, which will not be further described herein.

[0081] S103: Etching the at least two light-emitting structure layers so that the at least two light-emitting structure layers form a plurality of Micro-LED elements that are spaced apart.

[0082] As shown in FIG14 , at least two light-emitting structure layers are etched to form a plurality of spaced-apart Micro-LED elements 11. In some embodiments of the present application, after the at least two light-emitting structure layers are formed into a plurality of spaced-apart Micro-LED elements, a passivation layer 116 is formed on one side of the driving panel 10 to cover the light-emitting surface and side surfaces of the Micro-LED elements 11, as shown in FIG15 . The passivation layer 116 has a plurality of first openings 1161 and a plurality of second openings 1162. The plurality of first openings 1161 can respectively expose the first connection portions of the plurality of Micro-LED elements 11. The first connection portion is the portion of the light-emitting structure layer in the Micro-LED element 11 that is farthest from the driving panel and that can be electrically connected to the first contact 101 of the driving panel 10. The plurality of second openings 1162 can respectively expose the plurality of first contacts 101 of the driving panel 10.

[0083] Afterwards, as shown in FIG16 , a plurality of first electrodes 117 are formed on one side of the driving panel 10, and the plurality of first electrodes 117 are respectively arranged corresponding to the plurality of Micro-LED elements 11, so that the first electrodes 117 are located on the side of the passivation layer 116 covering the corresponding Micro-LED element 11 that is away from the driving panel 10, and the first electrodes 117 fill the first opening 1161 and the second opening 1162 adjacent to the corresponding Micro-LED element 11, so that the first electrode 117 electrically connects the first connection portion of the corresponding Micro-LED element 11 with the corresponding first contact 101, so that the light-emitting structure layer farthest from the driving panel 10 in any Micro-LED element 11 is electrically connected to the first contact 101 of the driving panel 10.

[0084] Afterwards, as shown in FIG17 , an etch stop layer 118 is formed on one side of the driving panel 10, so that the etch stop layer 118 is located on the side of the passivation layer 116 or the first electrode 117 facing away from the driving panel 10, and the etch stop layer 118 covers the light-emitting surface and side surfaces of the Micro-LED element 11 and the driving panel 10 between the Micro-LED elements 11, so that the etch stop layer 118 protects the Micro-LED element 11 from being etched by subsequent processes.

[0085] Then, a light-blocking wall is formed on one side of the driving panel 10, and is positioned between adjacent Micro-LED elements 11. As shown in FIG18 , a light-blocking layer 140 is first formed on one side of the driving panel 10, covering the entire driving panel 10. The light-blocking layer 140 is then patterned using a photolithography process or etched using an etching process, forming a light-blocking wall 14 between adjacent Micro-LED elements 11, as shown in FIG19 .

[0086] Then, a reflective layer 15 is formed on the side of the light-blocking wall 14 facing the Micro-LED element 11. The reflective layer 15 can reflect the light emitted by the Micro-LED element 11. As shown in Figure 20, a light-emitting layer 150 is first formed on one side of the driving panel 10. This reflective layer 150 covers the entire driving panel 10. Then, the light-emitting layer 150 is etched using an etching process, so that the light-emitting layer 150 forms a light-emitting layer 15 that wraps around the light-blocking wall 14 as shown in Figure 21. In some embodiments, after forming the filter element, a planarization process can be performed to remove the light-emitting layer 15 on the top of the light-blocking wall 14, so that the reflective layer 15 is only located on the side of the light-blocking wall 14 facing the Micro-LED element 11, as shown in Figure 2.

[0087] Then, as shown in FIG22 , a planarization layer 13 is formed on one side of the driving panel 10 . The planarization layer 13 covers the Micro-LED elements 11 and fills the grooves formed by the light-blocking walls 14 . The material of the planarization layer 13 includes a transparent photoresist material or a transparent inorganic material.

[0088] S104: forming a plurality of filter elements on one side of the driving panel, and disposing the plurality of filter elements corresponding to the plurality of Micro-LED elements, respectively, and disposing each of the plurality of filter elements at least above the corresponding Micro-LED element.

[0089] The plurality of filter elements 12 include at least two filter elements. Each filter element 12 can transmit one color of the mixed light emitted by the corresponding Micro-LED element 11 and filter other colors. At least two filter elements can transmit at least two colors of light and filter other colors of light.

[0090] As shown in FIG23 , a plurality of filter elements 12 are formed on one side of the driving panel 10, and the plurality of filter elements 12 are respectively arranged corresponding to the plurality of Micro-LED elements 11, wherein the plurality of filter elements 12 are respectively located in a plurality of grooves surrounded by light-blocking walls 14 and are located on the side of the planarization layer 13 facing away from the driving panel 10, and the filter elements 12 at least cover the light-emitting surfaces of the corresponding Micro-LED elements 11. The plurality of filter elements 12 can transmit at least two colors of mixed light emitted by the plurality of Micro-LED elements 11 and filter other colors of light.

[0091] In some embodiments of the present application, referring to FIG. 2 , the filter element 12 includes a first filter element 121, a second filter element 122, and a third filter element 123. The first filter element 121 can transmit a first color of mixed light emitted by the corresponding Micro-LED element 11 and filter out other colors of light. The second filter element 122 can transmit a second color of mixed light emitted by the corresponding Micro-LED element 11 and filter out other colors of light. The third filter element 123 can transmit a third color of mixed light emitted by the corresponding Micro-LED element 11 and filter out other colors of light. The first, second, and third colors of light transmitted by the filter element 12 are green, red, and blue, respectively, so that the green, red, and blue lights transmitted by the filter element 12 can be used for color display.

[0092] In some embodiments of the present application, the examples in which the Micro-LED element 11 includes three light-emitting structure layers and the filter element 12 includes three color filter elements are used for illustration. However, the present invention is not limited to this example. In other embodiments, the Micro-LED element 11 may include two, four, or even more light-emitting structure layers. For example, the Micro-LED element 11 may include a first light-emitting structure layer that emits a first color of light and a second light-emitting structure layer that emits a second color of light. In other embodiments, the filter element 12 may include two, four, or even more color filter elements. For example, the filter element 12 may include a first filter element that transmits the first color of light and filters other colors of light, and a second filter element that transmits the second color of light and filters other colors of light. These details are not further described here.

[0093] In some embodiments of the present application, as shown in Figure 7, the method for preparing the Micro-LED display chip also includes forming a plurality of micro lenses 17 on one side of the driving panel 10, and respectively setting the plurality of micro lenses 17 to correspond to the plurality of Micro-LED elements 11, so as to gather and / or collimate the light emitted by the corresponding Micro-LED elements 11 through the micro lenses 17.

[0094] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0095] The above embodiments merely represent several implementation methods of this specification. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the scope of this specification, and these modifications and improvements fall within the scope of protection of this specification. Therefore, the scope of protection of the patent in this specification shall be subject to the appended claims.

Claims

1. A Micro-LED display chip, characterized in that: It includes a driving panel and a plurality of Micro-LED elements and a plurality of filter elements located on one side of the driving panel. The plurality of Micro-LED elements are arranged at intervals, and each of the plurality of Micro-LED elements includes at least two light-emitting structure layers, the at least two light-emitting structure layers include a first light-emitting structure layer for emitting a first color light and a second light-emitting structure layer for emitting a second color light, the at least two light-emitting structure layers are stacked in a direction perpendicular to the driving panel, and the at least two light-emitting structure layers are connected in series, so that when the driving panel drives the Micro-LED element alone, the at least two light-emitting structure layers in the Micro-LED element emit light synchronously; The multiple filter elements are respectively arranged corresponding to the multiple Micro-LED elements, and each of the multiple filter elements is at least arranged above the light emitting surface of the corresponding Micro-LED element. The multiple filter elements include at least a first filter element and a second filter element. The first filter element is used to transmit the first color light and filter other color lights except the first color light, and the second filter element is used to transmit the second color light and filter other color lights except the second color light.

2. The Micro-LED display chip according to claim 1, characterized in that: The driving panel includes a plurality of first contacts and a plurality of second contacts, wherein the plurality of first contacts are respectively located between two adjacent Micro-LED elements among the plurality of Micro-LED elements, and the plurality of second contacts are respectively located under the plurality of Micro-LED elements; In the Micro-LED element, any two adjacent light-emitting structure layers among the at least two light-emitting structure layers are electrically connected; In the Micro-LED element, the light emitting structure layer farthest from the driving panel is electrically connected to the corresponding first contact point; In the Micro-LED element, the light emitting structure layer closest to the driving panel is electrically connected to the corresponding second contact point.

3. The Micro-LED display chip according to claim 2, characterized in that: Each of the at least two light emitting structure layers comprises a first doped semiconductor layer, a light emitting layer, and a second doped semiconductor layer which are stacked; In the Micro-LED element, in any two adjacent light-emitting structure layers of the at least two light-emitting structure layers, the first doped semiconductor layer of one light-emitting structure layer is electrically connected to the second doped semiconductor layer of another adjacent light-emitting structure layer, so as to realize the series connection of the two adjacent light-emitting structure layers; In the Micro-LED element, the first doped semiconductor layer of the light emitting structure layer farthest from the driving panel is electrically connected to the corresponding first contact, and the second doped semiconductor layer of the light emitting structure layer closest to the driving panel is electrically connected to the corresponding second contact.

4. The Micro-LED display chip according to any one of claims 1 to 3, characterized in that: The Micro-LED component further includes a bonding layer, wherein the bonding layer includes at least a first bonding layer and a second bonding layer; The first bonding layer is located between any two adjacent light-emitting structure layers among the at least two light-emitting structure layers, and the first bonding layer is used to bond and electrically connect the two adjacent light-emitting structure layers; The second bonding layer is located between the light emitting structure layer closest to the driving panel and the driving panel, and is used to bond the light emitting structure layer closest to the driving panel to the driving panel and to be electrically connected to a second contact of the driving panel.

5. The Micro-LED display chip according to claim 4, characterized in that: The material of the first bonding layer includes a transparent conductive material to allow light emitted by the at least two light emitting structure layers to pass through, and the material of the second bonding layer includes a reflective conductive material to reflect light emitted by the at least two light emitting structure layers.

6. The Micro-LED display chip according to any one of claims 1 to 5, characterized in that: It also includes a passivation layer, which covers the light emitting surface and side surfaces of the Micro-LED element; The passivation layer includes a plurality of first openings and a plurality of second openings; the plurality of first openings are used to respectively expose the first connection parts of the plurality of Micro-LED elements, wherein the first connection parts are the light-emitting structure layer in the Micro-LED elements farthest from the driving panel; the plurality of second openings are used to respectively expose the plurality of first contacts of the driving panel.

7. The Micro-LED display chip according to claim 6, characterized in that: Also included are a plurality of first electrodes; The plurality of first electrodes are respectively arranged corresponding to the plurality of Micro-LED elements, and each of the plurality of first electrodes electrically connects the first connection portion of the corresponding Micro-LED element to the corresponding first contact through the first opening and the second opening of the corresponding Micro-LED element.

8. The Micro-LED display chip according to claim 7, characterized in that: It also includes an etch stop layer, which is located on the side of the passivation layer or the first electrode away from the driving panel, and the etch stop layer covers the light emitting surface and side surfaces of the Micro-LED element.

9. The Micro-LED display chip according to any one of claims 1 to 8, characterized in that: It also includes a light blocking wall, which is located between two adjacent Micro-LED elements among the multiple Micro-LED elements; the side wall of the light blocking wall has a reflective layer, and the reflective layer is used to reflect the output light of the Micro-LED element.

10. The Micro-LED display chip according to any one of claims 1 to 9, characterized in that: A planarization layer is further provided between the filter element and the corresponding Micro-LED element, and the planarization layer allows light emitted by the Micro-LED element to pass through.

11. The Micro-LED display chip according to any one of claims 1 to 10, characterized in that: The at least two light emitting structure layers further include a third light emitting structure layer capable of emitting a third color light, and the plurality of filter elements further include a third filter element configured to transmit the third color light and filter other color lights except the third color light.

12. The Micro-LED display chip according to any one of claims 1 to 11, characterized in that: It also includes a plurality of micro lenses, which are respectively arranged corresponding to the plurality of Micro-LED elements, and each of the plurality of micro lenses is used to gather and / or collimate the light emitted by the corresponding Micro-LED element.

13. A method for preparing a Micro-LED display chip, characterized in that: include: At least two light-emitting structure layers are stacked and arranged in a direction perpendicular to the drive panel on one side of the drive panel, and the at least two light-emitting structure layers are connected in series, wherein the at least two light-emitting structure layers include a first light-emitting structure layer for emitting a first color light and a second light-emitting structure layer for emitting a second color light; Etching the at least two light-emitting structure layers so that the at least two light-emitting structure layers form a plurality of Micro-LED elements arranged at intervals, and when the driving panel drives each of the plurality of Micro-LED elements individually, the at least two light-emitting structure layers in the Micro-LED elements emit light synchronously; A plurality of filter elements are formed on one side of the driving panel, and the plurality of filter elements are respectively arranged corresponding to the plurality of Micro-LED elements, and each of the plurality of filter elements is at least arranged above the corresponding Micro-LED element, and the plurality of filter elements include at least a first filter element and a second filter element, the first filter element is used to transmit the first color light and filter other color lights except the first color light, and the second filter element is used to transmit the second color light and filter other color lights except the second color light.

14. The preparation method according to claim 13, characterized in that: The method of forming at least two light emitting structure layers stacked in a direction perpendicular to the drive panel on one side of the drive panel and connecting the at least two light emitting structure layers in series comprises: The first light emitting structure layer is arranged on the first substrate, wherein the first light emitting structure layer comprises a first doped semiconductor layer, a light emitting layer, and a second doped semiconductor layer which are stacked; The second light emitting structure layer is arranged on the second substrate, wherein the second light emitting structure layer comprises a first doped semiconductor layer, a light emitting layer and a second doped semiconductor layer which are stacked; Bonding the first light emitting structure layer to the driving panel via a second bonding layer, and electrically connecting the second doped semiconductor layer of the first light emitting structure layer to a second contact corresponding to the driving panel; removing the first substrate and exposing the first doped semiconductor layer of the first light emitting structure layer; Bonding the first light emitting structure layer to the second light emitting structure layer through a first bonding layer, so that the first doped semiconductor layer of the first light emitting structure layer is electrically connected to the second doped semiconductor layer of the second light emitting structure layer, so as to realize the series connection of two adjacent light emitting structure layers of the at least two light emitting structure layers; The second substrate is removed to expose the first doped semiconductor layer of the second light emitting structure layer.

15. The preparation method according to claim 14, characterized in that: Also includes: A third light emitting structure layer for emitting a third color light is arranged on the third substrate, wherein the third light emitting structure layer comprises a first doped semiconductor layer, a light emitting layer, and a second doped semiconductor layer which are stacked; The third light emitting structure layer is bonded to the second light emitting structure layer through a first bonding layer, and the first doped semiconductor layer of the second light emitting structure layer is electrically connected to the second doped semiconductor layer of the third light emitting structure layer, so as to realize the series connection of two adjacent light emitting structure layers of the at least two light emitting structure layers; removing the third substrate and exposing the first doped semiconductor layer of the third light emitting structure layer; The plurality of filter elements further include a third filter element, and the third filter element is used for transmitting the third color light and filtering other color lights except the third color light.

16. The preparation method according to any one of claims 13 to 15, characterized in that: After etching the at least two light-emitting structure layers so that the at least two light-emitting structure layers form a plurality of Micro-LED elements spaced apart from each other, the preparation method further comprises: A passivation layer is formed on one side of the driving panel to cover the light emitting surface and the side surface of the Micro-LED element, and the passivation layer has a plurality of first openings and a plurality of second openings; the plurality of first openings are used to respectively expose the first connection parts of the plurality of Micro-LED elements, the first connection parts being the light emitting structure layer in the Micro-LED element farthest from the driving panel; the plurality of second openings are used to respectively expose the plurality of first contacts of the driving panel; A plurality of first electrodes are formed on one side of the driving panel, and the plurality of first electrodes are respectively arranged corresponding to the plurality of Micro-LED elements, so that each of the plurality of first electrodes passes through the first opening and the second opening of the corresponding Micro-LED element, so that the first connection portion of the corresponding Micro-LED element is electrically connected to the corresponding first contact.

17. The preparation method according to claim 16, characterized in that: Also includes: An etch stop layer is formed on one side of the driving panel, so that the etch stop layer is located on the side of the passivation layer or the first electrode away from the driving panel, and the etch stop layer covers the light emitting surface and side surface of the Micro-LED element.

18. The preparation method according to any one of claims 13 to 17, characterized in that: Before forming a plurality of filter elements on one side of the driving panel, the preparation method further comprises: Forming a light-blocking wall on one side of the driving panel, and positioning the light-blocking wall between two adjacent Micro-LED elements among the plurality of Micro-LED elements; A reflective layer is formed on a side of the light blocking wall facing the Micro-LED element, and the reflective layer is used to reflect the emitted light of the Micro-LED element.

19. The preparation method according to claim 18, characterized in that: Also includes: A planarization layer is formed on one side of the driving panel, so that the planarization layer covers the Micro-LED element and fills the groove surrounded by the light-blocking wall, and the planarization layer allows light emitted by the Micro-LED element to pass through.

20. The Micro-LED display chip according to any one of claims 13 to 19, characterized in that: Also includes: A plurality of micro lenses are formed on one side of the driving panel. The plurality of micro lenses are respectively arranged corresponding to the plurality of Micro-LED elements. Each of the plurality of micro lenses is used to gather and / or collimate the light emitted by the corresponding Micro-LED element.

Images