Miniature light-emitting structure and miniature light-emitting device

Abstract

The utility model relates to a miniature light-emitting structure and a miniature light-emitting device.The miniature light-emitting structure comprises two light-emitting structures which are connected through a bonding layer and oppositely arranged, and one of the two light-emitting structures comprises a first semiconductor layer, a first light-emitting layer and a second semiconductor layer which are sequentially arranged in a stacked mode; the other light-emitting layer comprises a third semiconductor layer, a second light-emitting layer and a fourth semiconductor layer which are stacked in sequence, the third semiconductor layer and the second semiconductor layer are electrically connected through a bonding layer, the third semiconductor layer and the second semiconductor layer have the same polarity, and the first light-emitting layer and the second light-emitting layer have different light-emitting colors; the first groove and the second groove respectively penetrate to the bonding layer and the first semiconductor layer; and the first electrode and the second electrode are respectively arranged on the bottom wall surfaces of the first groove and the second groove, and at least parts of the first electrode and the second electrode protrude and are exposed on one side, deviating from the second light-emitting layer, of the fourth semiconductor layer, so that the manufacturing efficiency of the micro light-emitting diode full-color display device can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor light emitting, in particular to a micro light emitting structure and a micro light emitting device. BACKGROUND

[0002] Micro-LED (Micro-Light Emitting Diode) full-color display technology is a current hot topic. In order to realize full-color display, the most common technical solution in the industry is to grow single-color epitaxial wafers for RGB (red, green, and blue) respectively, then to cut the wafers into separate RGB (red, green, and blue) light emitting chips after chip processing, and then to use massive transfer technology to assemble and weld the chips on a substrate to realize RGB full-color display.

[0003] However, the micro light emitting diode full-color display device has the problem of low manufacturing efficiency. CONTENT OF THE UTILITY MODEL

[0004] Embodiments of the present application provide a micro light emitting structure and a micro light emitting device to solve the problem of low manufacturing efficiency of micro light emitting diode devices in related technologies.

[0005] To solve the above problems, the embodiments of the present application provide a micro light emitting structure, which comprises: a first light emitting structure and a second light emitting structure connected by a bonding layer and oppositely arranged, the first light emitting structure comprising a first semiconductor layer, a first light emitting layer and a second semiconductor layer arranged in sequence, the bonding layer being arranged on a side of the second semiconductor layer away from the first light emitting layer, the second light emitting structure comprising a third semiconductor layer, a second light emitting layer and a fourth semiconductor layer arranged in sequence on a side of the bonding layer away from the second semiconductor layer, and the third semiconductor layer and the second semiconductor layer being electrically connected through the bonding layer, the third semiconductor layer and the second semiconductor layer having the same polarity, the fourth semiconductor layer and the first semiconductor layer having the same polarity, the first semiconductor layer and the second semiconductor layer having different polarities, and the first light emitting layer and the second light emitting layer having different light emitting colors; a first recess and a second recess, the first recess penetrating through the second bonding layer or the first bonding layer from a surface of the second light emitting structure away from the first light emitting structure, and the second recess penetrating through the first semiconductor layer from a surface of the second light emitting structure away from the first light emitting structure; a first electrode and a second electrode, the first electrode being arranged on a bottom wall surface of the first recess, and the second electrode being arranged on a bottom wall surface of the second recess, and the first electrode and the second electrode both at least partially protruding and exposed on a side of the fourth semiconductor layer away from the second light emitting layer.

[0006] The micro light emitting structure further comprises a third electrode, the third electrode is arranged on the side of the fourth semiconductor layer away from the second light emitting layer, and the third electrode at least partially protrudes from the side of the fourth semiconductor layer away from the second light emitting layer.

[0007] The first electrode comprises a first height electrode and a first bonding electrode which are sequentially arranged on the bottom wall surface of the first recess, the second electrode comprises a second height electrode and a second bonding electrode which are sequentially arranged on the bottom wall surface of the second recess, and the heights of the first bonding electrode, the second bonding electrode and the third electrode relative to the plane of the bottom wall surface of the second recess are equal, and the heights of the first height electrode and the second height electrode relative to the plane of the bottom wall surface of the second recess are equal.

[0008] The micro light emitting structure further comprises a passivation layer covering the inner wall surface of the first recess, the inner wall surface of the second recess, and the first light emitting structure and the second light emitting structure, and the first electrode, the second electrode and the third electrode all penetrate the passivation layer.

[0009] The bonding layer comprises a first bonding layer and a second bonding layer which are sequentially arranged on the side of the second semiconductor layer away from the first light emitting layer, the first bonding layer has a first light transmission area, the second bonding layer has a second light transmission area, the orthographic projection of the second light transmission area on the first bonding layer at least partially overlaps the first light transmission area, and the light emitted by the second light emitting layer is emitted after sequentially passing through the second light transmission area and the first light transmission area.

[0010] The first light transmission area is provided with a first opening penetrating the first bonding layer, the second light transmission area is provided with a second opening penetrating the second bonding layer, and the first opening and the second opening are in communication.

[0011] To solve the above problems, the embodiment of the present application further provides a micro light emitting device, which comprises a first light emitting unit and a driving substrate, wherein the first light emitting unit comprises the micro light emitting structure of any one of the above, and in the first light emitting unit, the micro light emitting structure of the first light emitting unit is bonded to the driving substrate through the first electrode and the second electrode, and the fourth semiconductor layer of the micro light emitting structure of the first light emitting unit is electrically connected to the driving substrate.

[0012] The micro light emitting device further comprises a second light emitting unit, the second light emitting unit comprises the micro light emitting structure of any one of the above and a color conversion layer, and in the second light emitting unit, the micro light emitting structure of the second light emitting unit is bonded to the driving substrate through the first electrode and the second electrode, the color conversion layer covers the micro light emitting structure of the second light emitting unit and is configured to convert the light emitted by the first light emitting layer into light of a target color, and the light of the target color, the light reflected by the first light emitting layer and the light reflected by the second light emitting layer are used to synthesize white light.

[0013] The second light-emitting unit further comprises a light-blocking layer, and in the second light-emitting unit, the light-blocking layer covers the micro light-emitting structure of the second light-emitting unit, and the light-blocking layer is provided with an opening, the opening is located on the side of the micro light-emitting structure of the second light-emitting unit away from the driving substrate, penetrates through the light-blocking layer, and the color conversion layer fills the opening.

[0014] The micro light-emitting device further comprises a third light-emitting unit, the third light-emitting unit is bonded to the driving substrate, and the light reflected by the third light-emitting unit, the light reflected by the first light-emitting layer and the light reflected by the second light-emitting layer are used to synthesize white light.

[0015] The beneficial effects of the present application are: the micro light-emitting structure and the micro light-emitting device provided by the present application can obtain a micro light-emitting structure capable of emitting two colors of light (such as blue light and green light) at the same time by bonding and chip processing of two single-color micro light-emitting diode epitaxial wafers with different light-emitting colors, without the need to make quantum well layers of two light-emitting colors in the epitaxial stage, and the manufacturing process of the single-color micro light-emitting diode epitaxial wafer is mature and stable, thereby avoiding the yield risk that may be caused by the instability of the related process of making quantum well layers of two light-emitting colors in the epitaxial stage, and improving the yield of the dual-color micro light-emitting diode chip.

[0016] In addition, the micro light-emitting structure capable of emitting two colors of light at the same time provided by the present application can realize full-color display by matching a single-color micro light-emitting diode chip with other light-emitting colors (such as red), or can realize full-color display by matching quantum dots of other colors. In this way, compared with the scheme of separately making red, green and blue LEDs and separately performing massive transfer to realize full-color display, the scheme of realizing full-color display by matching a single-color micro light-emitting diode chip with other light-emitting colors in the micro light-emitting structure capable of emitting two colors of light at the same time in the present application can reduce the number of massive transfer. Compared with the scheme of realizing full-color display by matching a single-color micro light-emitting diode chip with two other colors of quantum dots, the scheme of realizing full-color display by matching a single other color of quantum dots in the micro light-emitting structure capable of emitting two colors of light at the same time in the present application can reduce the number of quantum dot printing. Therefore, by utilizing the micro light-emitting structure capable of emitting two colors of light at the same time in the present application to realize full-color display, the manufacturing efficiency and yield of the micro light-emitting diode full-color display device can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating any creative labor.

[0018] Figure 1 is a cross-sectional structure schematic diagram of a micro light emitting structure provided by an embodiment of the present application;

[0019] Figure 2 is another cross-sectional structure schematic diagram of a micro light emitting structure provided by an embodiment of the present application;

[0020] Figure 3 is another cross-sectional structure schematic diagram of a micro light emitting structure provided by an embodiment of the present application;

[0021] Figure 4 is another cross-sectional structure schematic diagram of a micro light emitting structure provided by an embodiment of the present application;

[0022] Figure 5 is a cross-sectional structure schematic diagram of a micro light emitting device provided by an embodiment of the present application;

[0023] Figure 6 is another cross-sectional structure schematic diagram of a micro light emitting device provided by an embodiment of the present application;

[0024] Figure 7 is another cross-sectional structure schematic diagram of a micro light emitting device provided by an embodiment of the present application;

[0025] Figure 8 is another cross-sectional structure schematic diagram of a micro light emitting device provided by an embodiment of the present application.

DETAILED DESCRIPTION

[0026] The embodiments of the present application will be described in further detail below with reference to the drawings and embodiments. It is particularly pointed out that the following embodiments are only used to illustrate the embodiments of the present application, but do not limit the scope of the embodiments of the present application. Similarly, the following embodiments are only part of the embodiments of the present application, not all embodiments, and all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the embodiments of the present application.

[0027] When describing the structure of a component, when a layer or a region is referred to as being "on" or "above" another layer or another region, it can be directly above the other layer or the other region, or other layers or regions can be included therebetween. And if the component is flipped, the layer or the region will be "under" or "below" the other layer or the other region. In addition, the features, structures or characteristics described below can be combined in any suitable manner in one or more embodiments.

[0028] In addition, the direction terms mentioned in the embodiments of the present application, such as [up], [down], [front], [back], [left], [right], [inward], [outward], [side] and the like, are only the directions of reference to the attached drawings. Therefore, the direction terms used are used to illustrate and understand the embodiments of the present application, and not to limit the embodiments of the present application. In each figure, similar structures are represented by the same reference numerals. For the sake of clarity, each part in the drawings is not drawn to scale. In addition, some related parts can not be shown in the drawings.

[0029] Micro-LED full-color display technology is a current hot topic. There are different technical solutions in the market to achieve full-color display, such as massive transfer, three-color module optical synthesis, quantum dot color conversion, in-situ epitaxial growth, and three-color stacking bonding. These solutions have their own characteristics. Among them, the first three technical solutions are currently mentioned relatively most. In particular, the massive transfer and quantum dot color conversion solutions have been researched and laid out by many companies. This also reflects the relative maturity and recognition of the technology.

[0030] For the massive transfer solution, a large number of small chips need to be precisely positioned and transferred, which requires high-precision equipment and control technology. During the transfer process, due to the large number of chips, even a small percentage of failure can cause a significant decrease in overall yield. Transferring a large number of chips requires a long time and low production efficiency. If failures or defects occur during the transfer process, it is very difficult and time-consuming to repair these defects, increasing the production complexity.

[0031] The key to the quantum dot color conversion solution is quantum dots, which have significant advantages in the display field, such as high color purity, wide color gamut, high brightness, and contrast ratio. However, it also has some disadvantages, such as toxicity issues, manufacturing complexity, uniformity and consistency, and reliability issues.

[0032] In addition, related technologies directly grow blue-green double-color or even red-green-blue three-color epitaxial stacks during the epitaxial phase to achieve full-color display, or vertically stack and bond light-emitting chips of three light-emitting colors to achieve full-color display. The starting point of these solutions is very novel, but the actual manufacturing difficulties are obvious. The related processes of these solutions can cause yield risk and light-emitting efficiency problems.

[0033] To solve the above problems, the embodiment of the present application provides a micro light emitting structure and a micro light emitting device. The micro light emitting structure comprises a first light emitting structure and a second light emitting structure connected by a bonding layer and oppositely arranged, and a first recess, a second recess, a first electrode and a second electrode. The first light emitting structure comprises a first semiconductor layer, a first light emitting layer and a second semiconductor layer arranged in sequence, the bonding layer is arranged on the side of the second semiconductor layer away from the first light emitting layer, the second light emitting structure comprises a third semiconductor layer, a second light emitting layer and a fourth semiconductor layer arranged in sequence on the side of the first bonding layer away from the second semiconductor layer, and the third semiconductor layer and the second semiconductor layer are electrically connected by the bonding layer. The third semiconductor layer and the second semiconductor layer have the same polarity, the fourth semiconductor layer and the first semiconductor layer have the same polarity, the first semiconductor layer and the second semiconductor layer have different polarities, and the first light emitting layer and the second light emitting layer have different light emitting colors. The first recess penetrates from the surface of the second light emitting structure away from the first light emitting structure to the second bonding layer or the first bonding layer, and the second recess penetrates from the surface of the second light emitting structure away from the first light emitting structure to the first semiconductor layer. The first electrode is arranged on the bottom wall surface of the first recess, the second electrode is arranged on the bottom wall surface of the second recess, and the first electrode and the second electrode at least partially protrude and are exposed on the side of the fourth semiconductor layer away from the second light emitting layer. In this way, by directly bonding two single-color micro light emitting diode epitaxial wafers with different light emitting colors, and micro-nano processing the structure obtained by bonding, a micro light emitting structure capable of emitting two colors of light (such as blue light and green light) at the same time can be obtained. The epitaxial layer stacked with two light emitting colors does not need to be made in the epitaxial stage, and the manufacturing process of the single-color micro light emitting diode epitaxial wafer is mature and stable, thereby avoiding the yield risk and light emitting efficiency problems caused by the instability of the related process of making the epitaxial layer stacked with two light emitting colors in the epitaxial stage, and improving the yield and light emitting efficiency of the dual-color micro light emitting diode chip.

[0034] Also, the micro light emitting structure capable of emitting two colors of light provided by the embodiments of the present application can realize full-color display by being combined with a single-color micro light emitting diode chip having other light emitting colors (for example, red), or by being combined with quantum dots of other colors. Thus, compared with the massive transfer scheme, the scheme of realizing full-color display by using the micro light emitting structure capable of emitting two colors of light provided by the embodiments of the present application can reduce the transfer and repair of single-color blue light or green light once. Compared with the quantum dot color conversion scheme, the scheme of realizing full-color display by using the micro light emitting structure capable of emitting two colors of light provided by the embodiments of the present application only needs to perform printing of red quantum dots once, without the need of preparing and printing green quantum dots, thereby reducing the number of times of quantum dot printing and thus reducing the process risk. Therefore, compared with the massive transfer scheme and the quantum dot color conversion scheme, the micro light emitting structure capable of emitting two colors of light can be prepared by using the existing epitaxy and micro-nano processing technology in the embodiments of the present application, and the full-color display can be realized by using the micro light emitting structure capable of emitting two colors of light, thereby effectively improving the manufacturing efficiency of the micro light emitting diode full-color display device.

[0035] The embodiments of the present application will be described in detail below with specific examples. It should be noted that the embodiments of the present application can be presented in various forms, and some examples will be described below.

[0036] Please refer to Figure 1 , Figure 1 is a schematic diagram of the cross-sectional structure of the micro light emitting structure provided by the embodiments of the present application. As shown in Figure 1 , the micro light emitting structure 10 includes a first light emitting structure 11 and a second light emitting structure 12 connected by a bonding layer 17 and oppositely arranged. The first light emitting structure 11 includes a first semiconductor layer 111, a first light emitting layer 112 and a second semiconductor layer 113 arranged in sequence. The bonding layer 17 is arranged on the side of the second semiconductor layer 113 away from the first light emitting layer 112. The second light emitting structure 12 includes a third semiconductor layer 122, a second light emitting layer 123 and a fourth semiconductor layer 124 arranged in sequence on the side of the bonding layer 17 away from the second semiconductor layer 113. Also, the first light emitting structure 11 and the second light emitting structure 12 are bonded together by the bonding layer 17, so that the stacked structure of two single-color light epitaxial layers can be obtained by directly bonding the existing different single-color light epitaxial layers (for example, blue light epitaxial layers and green light epitaxial layers), without the need of adjusting the epitaxial growth process of different color light (for example, blue light epitaxial growth process and green light epitaxial growth process) in the epitaxial growth stage, thereby avoiding the process risk and epitaxial quality risk caused thereby and improving the yield of the dual-color micro light emitting diode chip.

[0037] And, in the micro light emitting structure 10, the third semiconductor layer 122 and the second semiconductor layer 113 are electrically connected through the bonding layer 17, and the third semiconductor layer 122 and the second semiconductor layer 113 have the same polarity, the fourth semiconductor layer 124 and the first semiconductor layer 111 have the same polarity, the first semiconductor layer 111 and the second semiconductor layer 113 have different polarities, and the first light emitting layer 112 and the second light emitting layer 123 have different light emitting colors, so that not only the first light emitting structure 11 and the second light emitting structure 12 in the micro light emitting structure 10 can be connected side by side, but also the micro light emitting structure 10 can emit two colors of light (such as blue light and green light) at the same time.

[0038] Specifically, as shown in Figure 1 The micro light emitting structure 10 can further include a first recess 13A, a second recess 13B, a first electrode T1 and a second electrode T2. The first recess 13A penetrates from the surface of the second light emitting structure 12 away from the first light emitting structure 11 to the bonding layer 17, and the second recess 13B penetrates from the surface of the second light emitting structure 12 away from the first light emitting structure 11 to the first semiconductor layer 111. The first electrode T1 is arranged on the bottom wall surface of the first recess 13A, and the second electrode T2 is arranged on the bottom wall surface of the second recess 13B. And the first electrode T1 and the second electrode T2 are at least partially exposed on the side of the fourth semiconductor layer 124 away from the second light emitting layer 123, that is, the height of the first electrode T1 and the second electrode T2 relative to the plane of the bottom wall surface of the second recess 13B is greater than the height of the fourth semiconductor layer 124 relative to the plane of the bottom wall surface of the second recess 13B, so as to ensure that the micro light emitting structure 10 can be bonded with other structures (such as a driving substrate) through the first electrode T1 and the second electrode T2.

[0039] And, in particular implementation, as shown in Figure 1 The micro light emitting structure 10 can further include a third electrode T3 arranged on the side of the fourth semiconductor layer 124 away from the second light emitting layer 123, and the third electrode T3 can be at least partially exposed on the side of the fourth semiconductor layer 124 away from the second light emitting layer 123, that is, the height of the third electrode T3 relative to the plane of the bottom wall surface of the second recess 13B can be greater than the height of the fourth semiconductor layer 124 relative to the plane of the bottom wall surface of the second recess 13B, so as to ensure that the micro light emitting structure 10 can be bonded with other structures (such as a driving substrate) through the first electrode T1, the second electrode T2 and the third electrode T3.

[0040] It should be noted that, in this embodiment, the micro-light-emitting structure 10 can emit up to two colors of light at the same time. That is, the micro-light-emitting structure 10 can have two light-emitting states: a state that emits only one color of light (e.g., blue light); and a state that emits two colors of light (e.g., blue light and green light) at the same time.

[0041] Furthermore, in specific implementation, during the use of the aforementioned micro-light-emitting structure 10, by providing corresponding driving signals (e.g., driving voltages) to the first electrode T1 and the second electrode T2 respectively, and not providing corresponding driving signals to the fourth semiconductor layer 124 (or the aforementioned third electrode T3), it is possible to drive only the first light-emitting layer 112 to emit light, without driving the second light-emitting layer 123 to emit light, thus enabling the aforementioned micro-light-emitting structure 10 to emit light of only one color; or, by providing corresponding driving signals to the first electrode T1, the second electrode T2 and the fourth semiconductor layer 124 (or the aforementioned third electrode T3) respectively, it is possible to drive the first light-emitting layer 112 and the second light-emitting layer 123 to emit light simultaneously, thus enabling the aforementioned micro-light-emitting structure 10 to emit light of two colors simultaneously.

[0042] It is understood that the aforementioned micro-light-emitting structure 10 may include the aforementioned third electrode T3 (e.g., Figure 1 (as shown), or may not include the aforementioned third electrode T3 (as shown). Figure 2 (As shown). Furthermore, when it is necessary to drive the second light-emitting layer 123 to emit light, in the case where the micro-light-emitting structure 10 includes the third electrode T3, as shown... Figure 1 As shown, the second light-emitting layer 123 can be driven to emit light by directly providing a corresponding driving signal to the third electrode T3; however, in the case where the micro-light-emitting structure 10 does not include the third electrode T3, as... Figure 2 As shown, the second light-emitting layer 123 can be driven to emit light by directly providing a corresponding driving signal to the fourth semiconductor layer 124.

[0043] In this embodiment, as Figure 1 As shown, the height of the first electrode T1 relative to the plane containing the bottom wall of the second groove 13B can be equal to the height of the second electrode T2 relative to the plane containing the bottom wall of the second groove 13B. Furthermore, in the above embodiment where the micro-light-emitting structure 10 also includes a third electrode T3, as... Figure 1As shown, the height of the third electrode T3 relative to the plane of the bottom wall surface of the second groove 13B can be equal to the height of the first electrode T1 relative to the plane of the bottom wall surface of the second groove 13B and the height of the second electrode T2 relative to the plane of the bottom wall surface of the second groove 13B. In this way, it is beneficial to reduce the process difficulty of bonding the micro light emitting structure 10 to other structures (such as a driving substrate) through the first electrode T1, the second electrode T2 and the third electrode T3.

[0044] Specifically, as Figure 1 shown, the first electrode T1 can include a first height adjustment electrode 14A and a first bonding electrode 15A which are sequentially stacked on the bottom wall surface of the first groove 13A, and the second electrode T2 can include a second height adjustment electrode 14B and a second bonding electrode 15B which are sequentially stacked on the bottom wall surface of the second groove 13B. In addition, the height of the first bonding electrode 15A relative to the plane of the bottom wall surface of the second groove 13B can be equal to the height of the second bonding electrode 15B relative to the plane of the bottom wall surface of the second groove 13B, and the height of the first height adjustment electrode 14A relative to the plane of the bottom wall surface of the second groove 13B can be equal to the height of the second height adjustment electrode 14B relative to the plane of the bottom wall surface of the second groove 13B.

[0045] In addition, in the above-mentioned embodiment in which the micro light emitting structure 10 further includes a third electrode T3, as Figure 1 shown, the third electrode T3 can specifically be a third bonding electrode 15C, and the surface (i.e., the upper surface) of the first height adjustment electrode 14A facing away from the bottom wall surface of the first groove 13A and the surface (i.e., the upper surface) of the second height adjustment electrode 14B facing away from the bottom wall surface of the second groove 13B can be in the same plane as the surface (i.e., the lower surface) of the third bonding electrode 15C facing the first light emitting structure 11. In this way, it is convenient to synchronously prepare the first bonding electrode 15A, the second bonding electrode 15B and the third bonding electrode 15C, and to reduce the process difficulty of preparation.

[0046] In some examples, the material of the first height adjustment electrode 14A can include at least one of titanium (Ti), gold (Au), platinum (Pt), nickel (Ni) and aluminum (Al) and other metal materials. The material of the second height adjustment electrode 14B can include at least one of titanium (Ti), gold (Au), platinum (Pt), nickel (Ni) and aluminum (Al) and other metal materials. In addition, in specific implementation, the first height adjustment electrode 14A and the second height adjustment electrode 14B can have the same material and can be synchronously formed.

[0047] In some examples, the material of the first bonding electrode 15A can include at least one of gold (Au), indium (In), tin (Sn), and copper (Cu). The material of the second bonding electrode 15B can include at least one of gold (Au), indium (In), tin (Sn), and copper (Cu). The material of the third bonding electrode 15C can include at least one of gold (Au), indium (In), tin (Sn), and copper (Cu). In specific implementations, the first bonding electrode 15A, the second bonding electrode 15B, and the third bonding electrode 15C can have the same material and can be formed synchronously.

[0048] In examples, the first bonding electrode 15A, the second bonding electrode 15B, and the third bonding electrode 15C can each have a partial spherical shape. In specific implementations, the first bonding electrode 15A, the second bonding electrode 15B, and the third bonding electrode 15C can each be formed by adopting a reflow soldering process.

[0049] In the micro light emitting structure 10, the first light emitting layer 112 and the second light emitting layer 123 can be quantum well layers, for example, indium gallium nitride quantum well layers or indium gallium nitride / gallium nitride multi-quantum well layers. The first semiconductor layer 111 and the fourth semiconductor layer 124 can be one of N-type semiconductor layers and P-type semiconductor layers, and the second semiconductor layer 113 and the third semiconductor layer 122 can be the other of N-type semiconductor layers and P-type semiconductor layers. The N-type semiconductor layers can be N-type gallium nitride layers or N-type gallium arsenide layers, and the P-type semiconductor layers can be P-type gallium nitride layers or P-type aluminum gallium nitride layers.

[0050] In some examples, one of the first light emitting structure 11 and the second light emitting structure 12 can emit blue light, and the other of the first light emitting structure 11 and the second light emitting structure 12 can emit green light. In examples, the first light emitting structure 11 can emit blue light, and the second light emitting structure 12 can emit green light. In this way, the blue light emitted by the first light emitting structure 11 can be emitted to the light emitting side of the micro light emitting structure 10 (i.e., the side of the first light emitting structure 11 facing away from the second light emitting structure 12) without passing through the second light emitting structure 12, so that the brightness of the blue light can be ensured, the difference in brightness between the blue light and the green light emitted by the micro light emitting structure 10 can be reduced, and the full-color display effect can be improved.

[0051] In some examples, the first semiconductor layer 111 and the fourth semiconductor layer 124 can both be N-type semiconductor layers, and the second semiconductor layer 113 and the third semiconductor layer 122 can both be P-type semiconductor layers. Accordingly, the first electrode T1 can be a P-type electrode electrically connected to the P-type semiconductor layer in the first light-emitting structure 11 and the P-type semiconductor layer in the second light-emitting structure 12, the second electrode T2 can be an N-type electrode electrically connected to the N-type semiconductor layer in the first light-emitting structure 11, and the third electrode T3 can be another N-type electrode electrically connected to the N-type semiconductor layer in the second light-emitting structure 12, so that the first light-emitting structure 1 and the second light-emitting structure 12 share the same P-type electrode and have independent N-type electrodes, respectively.

[0052] In other examples, the first semiconductor layer 111 and the fourth semiconductor layer 124 can both be P-type semiconductor layers, and the second semiconductor layer 113 and the third semiconductor layer 122 can both be N-type semiconductor layers. Accordingly, the first electrode T1 can be an N-type electrode electrically connected to the N-type semiconductor layer in the first light-emitting structure 11 and the N-type semiconductor layer in the second light-emitting structure 12, the second electrode T2 can be a P-type electrode electrically connected to the P-type semiconductor layer in the first light-emitting structure 11, and the third electrode T3 can be another P-type electrode electrically connected to the P-type semiconductor layer in the second light-emitting structure 12, so that the first light-emitting structure 1 and the second light-emitting structure 12 share the same N-type electrode and have independent P-type electrodes, respectively.

[0053] In addition, as shown in FIG. 1A, the first electrode T1 and the second electrode T2 can be located at opposite sides of the micro light-emitting structure 10 (for example, the left side and the right side as shown in FIG. 1A). Figure 1 In addition, as shown in FIG. 1A, the first electrode T1 and the second electrode T2 can be located at opposite sides of the micro light-emitting structure 10 (for example, the left side and the right side as shown in FIG. 1A). Figure 1 In addition, as shown in FIG. 1A, the first electrode T1 and the second electrode T2 can be located at opposite sides of the micro light-emitting structure 10 (for example, the left side and the right side as shown in FIG. 1A). Figure 1 In addition, as shown in FIG. 1A, the first electrode T1 and the second electrode T2 can be located at opposite sides of the micro light-emitting structure 10 (for example, the left side and the right side as shown in FIG. 1A).

[0054] In some embodiments, as shown in FIG. 1A, the first electrode T1 and the second electrode T2 can be located at opposite sides of the micro light-emitting structure 10 (for example, the left side and the right side as shown in FIG. 1A). Figure 1As shown, the first light-emitting structure 11 may further include a first current diffusion layer 115, which is disposed between the bonding layer 17 and the second semiconductor layer 113. The first current diffusion layer 115 can distribute the current very uniformly throughout the second semiconductor layer 113 (e.g., a P-type gallium nitride layer), thereby effectively improving the luminous efficiency of the first light-emitting structure 11. The second light-emitting structure 12 may further include a second current diffusion layer 125, which is disposed between the bonding layer 17 and the third semiconductor layer 122. The second current diffusion layer 125 can distribute the current very uniformly throughout the third semiconductor layer 122 (e.g., a P-type gallium nitride layer), thereby effectively improving the luminous efficiency of the second light-emitting structure 12.

[0055] In some examples, the first current diffusion layer 115 can be fabricated by depositing multiple layers of metal (e.g., titanium Ti, aluminum Al, gold Au, platinum Pt, or nickel Ni) or semiconductor oxides (e.g., indium tin oxide ITO or zinc oxide ZnO) on the surface of the second semiconductor layer 113 opposite to the first light-emitting layer 112 to create current conduction. The second current diffusion layer 125 can be fabricated by depositing multiple layers of metal (e.g., titanium Ti, aluminum Al, gold Au, platinum Pt, or nickel Ni) or semiconductor oxides (e.g., indium tin oxide ITO or zinc oxide ZnO) on the surface of the third semiconductor layer 122 opposite to the second light-emitting layer 123 to create current conduction.

[0056] In some embodiments, such as Figure 1 As shown, the first light-emitting structure 11 may further include a first substrate 116, which supports the film structure located thereon. Specifically, the micro light-emitting structure 10 may further include a buffer layer 117, which may be disposed on one side of the first substrate 116, and the first semiconductor layer 111, the first light-emitting layer 112, and the second semiconductor layer 113 may be sequentially stacked on the side of the buffer layer 117 facing away from the first substrate 116. Furthermore, the buffer layer 117 can alleviate the stress caused by lattice mismatch and thermal expansion coefficient mismatch between the first semiconductor layer 111 and the first substrate 116.

[0057] In some examples, the first substrate 116 may be a sapphire substrate, a silicon substrate, or a silicon carbide substrate. The material of the buffer layer 117 may include buffer materials such as silicon nitride, silicon oxide, gallium nitride, or aluminum nitride. For example, the buffer layer 117 may specifically be an unintentionally doped gallium nitride (U-GaN) layer.

[0058] In some embodiments, such as Figure 3As shown, the micro light emitting structure 10 can further include a passivation layer 16 covering the inner wall surface of the first recess 13A, the inner wall surface of the second recess 13B, and the first light emitting structure 11 and the second light emitting structure 12, and the first electrode T1 (e.g., the first pad electrode 14A), the second electrode T2 (e.g., the second pad electrode 14B), and the third electrode T3 (e.g., the third bonding electrode 1C) can all penetrate the passivation layer 16. In this way, not only can the passivation layer 16 effectively prevent the inner wall surface of the first recess 13A, the inner wall surface of the second recess 13B, and the first light emitting structure 11 and the second light emitting structure 12 from being eroded by external water and oxygen, thereby improving product reliability, but the passivation layer 16 can also electrically isolate the first electrode T1 from the sidewall of the second light emitting structure 12, and electrically isolate the second electrode T2 from the sidewall of the second light emitting structure 12 and the sidewall of the first light emitting structure 11, thereby effectively preventing the conductive material used to prepare the first electrode T1 and the second electrode T2 from forming conductive residues on the sidewalls of the first light emitting structure 11 and the second light emitting structure 12 during the preparation of the first electrode T1 and the second electrode T2, thereby further improving product reliability.

[0059] In some examples, the material of the passivation layer 16 can include at least one of silicon oxide, silicon nitride, and aluminum oxide.

[0060] In some embodiments, as Figure 3 As shown, the second recess 13B can penetrate the entire film layer of the second light emitting structure 12, the bonding layer 17, and the first current diffusion layer 115, the second semiconductor layer 113, the first light emitting layer 112, and part of the first semiconductor layer 111 of the first light emitting structure 11 in order from top to bottom, to ensure that the first semiconductor layer 111 can be exposed via the second recess 14B.

[0061] In the above-mentioned embodiments in which the micro light emitting structure 10 further includes the third electrode T3, as Figure 1 As shown, the third electrode T3 can be partially inserted into the interior of the fourth semiconductor layer 124 to ensure good electrical contact between the third electrode T3 and the fourth semiconductor layer 123.

[0062] In some embodiments, the first recess 13A can penetrate the entire film layer of the second light emitting structure 12 and part of the bonding layer 17 in order from top to bottom, to ensure that the bonding layer 17 can be exposed via the first recess 13A.

[0063] In some examples, the included angle between the side wall surface and the bottom wall surface of the first groove 13A can be between 90 degrees and 120 degrees, such as 90 degrees, 100 degrees, 110 degrees, or 120 degrees, etc. The included angle between the side wall surface and the bottom wall surface of the second groove 13B can be between 90 degrees and 120 degrees, such as 90 degrees, 100 degrees, 110 degrees, or 120 degrees, etc.

[0064] Specifically, in the above-mentioned embodiments in which the micro light emitting structure 10 further comprises a passivation layer 16, the first electrode T1 and the second electrode T2 can both penetrate the passivation layer 16 and neither cover the passivation layer 16 (as shown in FIG. 2A) ; or, the first electrode T1 and the second electrode T2 can both penetrate the passivation layer 16 and partially cover the passivation layer 16 (as shown in FIG. 2B). Figure 3 Figure 1

[0065] Specifically, in the above-mentioned embodiments in which the micro light emitting structure 10 further comprises a passivation layer 16, the first electrode T1 can be spaced apart from the passivation layer 16 covering the side wall of the second light emitting structure 12, and the second electrode T2 can be spaced apart from the passivation layer 16 covering the side walls of the second light emitting structure 12 and the first light emitting structure 11 (as shown in FIG. 3A) ; or, the first electrode T1 can be arranged without a gap between the passivation layer 16 covering the side wall of the second light emitting structure 12, and the second electrode T2 can be arranged without a gap between the passivation layer 16 covering the side walls of the second light emitting structure 12 and the first light emitting structure 11 (as shown in FIG. 3B). Figure 3 Figures 1 to 3

[0066] And it should be noted that by spacing apart the first electrode T1 from the passivation layer 16 covering the side wall of the second light emitting structure 12, and spacing apart the second electrode T2 from the passivation layer 16 covering the side walls of the second light emitting structure 12 and the first light emitting structure 11, a part of the light emitted by the second light emitting layer 123 in the second light emitting structure 12 can be emitted after passing through the gap between the first electrode T1 and the passivation layer 16 covering the side wall of the second light emitting structure 12, and another part of the light emitted by the second light emitting layer 123 in the second light emitting structure 12 can be emitted after passing through the gap between the second electrode T2 and the passivation layer 16 covering the side walls of the second light emitting structure 12 and the first light emitting structure 11, thus the light emitting efficiency of the second light emitting structure 12 in the micro light emitting structure 10 can be improved to some extent.

[0067] ​​​​In some embodiments, the bonding layer 17 can be made of a light-transmissive conductive material, which can be a transparent conductive material, for example, or a non-light-transmissive conductive material, which can include at least one of gold (Au), indium (In), tin (Sn), copper (Cu), and other metal materials.

[0068] In addition, it should be noted that by using a light-transmissive conductive material to make the bonding layer 17, at least part of the light emitted by the second light-emitting layer 123 of the second light-emitting structure 12 and propagating to the bonding layer 17 can be transmitted through the bonding layer 17 and then emitted from the light-emitting side of the micro light-emitting structure 10 (i.e., the side of the first light-emitting structure 11 facing away from the second light-emitting structure 11), thereby improving the light-emitting efficiency of the second light-emitting structure 12 of the micro light-emitting structure 10.

[0069] In the above embodiments, as shown in Figure 4 the bonding layer 17 can include a first bonding layer 171 and a second bonding layer 172 stacked in sequence on the side of the second semiconductor layer 113 facing away from the first light-emitting layer 112. In addition, the first bonding layer 171 and the second bonding layer 172 are bonded and connected to realize the bonding between the first light-emitting structure 11 and the second light-emitting structure 12.

[0070] In some embodiments, as shown in Figure 4 the first bonding layer 171 can have a first light-transmissive region 114A, the second bonding layer 172 can have a second light-transmissive region 121A, and the second light-transmissive region 121A can have a first light-transmissive region 114A at least partially overlapping with the first light-transmissive region 114A. The light emitted by the second light-emitting layer 123 can be emitted after sequentially passing through the second light-transmissive region 141A and the first light-transmissive region 114A.

[0071] Specifically, as shown in Figure 4 the first bonding layer 171 can further have a first light-blocking region 114B located at the periphery of the first light-transmissive region 114A, and the second bonding layer 172 can further have a second light-blocking region 121B located at the periphery of the second light-transmissive region 121A. In addition, the light emitted by the second light-emitting layer 123 cannot pass through the second light-blocking region 121B and the first light-blocking region 114B. In this way, by making part of the first bonding layer 171 and the second bonding layer 172 light-transmissive, the blocking of the light emitted by the second light-emitting layer 123 by the first bonding layer 171 and the second bonding layer 172 can be reduced, thereby improving the light-emitting efficiency of the second light-emitting structure 12 of the micro light-emitting structure 10.

[0072] In some examples, as shown in Figure 4As shown, the number of the first light-transmitting areas 114A can be multiple, and the first light-blocking area 114B can be located between the multiple first light-transmitting areas 114A. The number of the second light-transmitting areas 121A can be multiple, and the second light-blocking area 121B can be located between the multiple second light-transmitting areas 121A. Moreover, the orthographic projection of each second light-transmitting area 121A on the first bonding layer 171 can at least partially overlap with at least one first light-transmitting area 114A, so that the light emitted by the second light-emitting layer 123 and propagating to the second light-transmitting area 121A can at least partially pass through the second light-transmitting area 121A and the first light-transmitting area 114A and then be emitted from the light-emitting side (i.e., the side of the first light-emitting structure 11 facing away from the second light-emitting structure 12) of the micro light-emitting structure 10, so as to improve the light-emitting efficiency of the second light-emitting structure 12 in the micro light-emitting structure 10.

[0073] In some embodiments, as shown in FIG. 1A, the first light-transmitting area 114A can be provided with a first opening 114C penetrating the first bonding layer 171, and the second light-transmitting area 121A can be provided with a second opening 121C penetrating the second bonding layer 172, and the first opening 114C and the second opening 121C are in communication, so as to realize the light-transmitting function of the second light-transmitting area 121A and the first light-transmitting area 114A. Figure 4 In some embodiments, as shown in FIG. 1A, the first light-transmitting area 114A can be provided with a first opening 114C penetrating the first bonding layer 171, and the second light-transmitting area 121A can be provided with a second opening 121C penetrating the second bonding layer 172, and the first opening 114C and the second opening 121C are in communication, so as to realize the light-transmitting function of the second light-transmitting area 121A and the first light-transmitting area 114A.

[0074] Figure 4 In some embodiments, as shown in FIG. 1A, the first light-transmitting area 114A can be provided with a first opening 114C penetrating the first bonding layer 171, and the second light-transmitting area 121A can be provided with a second opening 121C penetrating the second bonding layer 172, and the first opening 114C and the second opening 121C are in communication, so as to realize the light-transmitting function of the second light-transmitting area 121A and the first light-transmitting area 114A.

[0075] In some embodiments, as shown in FIG. 1A, the first light-transmitting area 114A can be provided with a first opening 114C penetrating the first bonding layer 171, and the second light-transmitting area 121A can be provided with a second opening 121C penetrating the second bonding layer 172, and the first opening 114C and the second opening 121C are in communication, so as to realize the light-transmitting function of the second light-transmitting area 121A and the first light-transmitting area 114A. Figure 5 In some embodiments, as shown in FIG. 1A, the first light-transmitting area 114A can be provided with a first opening 114C penetrating the first bonding layer 171, and the second light-transmitting area 121A can be provided with a second opening 121C penetrating the second bonding layer 172, and the first opening 114C and the second opening 121C are in communication, so as to realize the light-transmitting function of the second light-transmitting area 121A and the first light-transmitting area 114A.

[0076] ​As can be seen from the above, the micro-light-emitting structure provided in this application embodiment can obtain a micro-light-emitting structure that can emit two colors of light simultaneously (e.g., blue and green light) by bonding two monochromatic micro-light-emitting diode epitaxial wafers with different emission colors and processing the chip. It does not require the fabrication of quantum well layers with stacked emission colors in the epitaxial stage. Moreover, the fabrication process of monochromatic micro-light-emitting diode epitaxial wafers is mature and stable, thereby avoiding the yield risk that may be caused by the instability of the related process of fabricating quantum well layers with stacked emission colors in the epitaxial stage, improving the yield of dual-color micro-light-emitting diode chips. Furthermore, by using this micro-light-emitting structure that can emit two colors of light simultaneously to achieve full-color display, the fabrication efficiency and yield of micro-light-emitting diode full-color display devices can be improved.

[0077] Please see Figure 5 , Figure 5 This is a schematic cross-sectional view of the micro light-emitting device provided in an embodiment of this application. Figure 5 As shown, the micro light-emitting device 1 includes a first light-emitting unit 100A and a driving substrate 200. The first light-emitting unit 100A includes a micro light-emitting structure 10 as described above. In the first light-emitting unit 100A, the micro light-emitting structure 10 of the first light-emitting unit 100A is bonded to the driving substrate 200 through a first electrode T1 and a second electrode T2. The fourth semiconductor layer 124 of the micro light-emitting structure 10 of the first light-emitting unit 100A is electrically connected to the driving substrate 200, thereby enabling the driving substrate 200 to drive the micro light-emitting structure 10 in the first light-emitting unit 100A to emit light of two colors simultaneously, so as to realize the display function of the micro light-emitting device 1.

[0078] Specifically, such as Figure 5 As shown, in the first light-emitting unit 100A, the micro light-emitting structure 10 of the first light-emitting unit 100A may include the third electrode T3 in the above embodiment of the micro light-emitting structure, and the micro light-emitting structure 10 of the first light-emitting unit 100A can be bonded to the driving substrate 200 through the first electrode T1, the second electrode T2 and the third electrode T3.

[0079] Specifically, such as Figure 5 As shown, in the first light-emitting unit 100A, the outermost layer of the micro light-emitting structure 10 of the first light-emitting unit 100A away from the driving substrate 200 can be the first semiconductor layer 111. That is, the micro light-emitting structure 10 of the first light-emitting unit 100A may not include the first substrate 116 and the buffer layer 117 in the above micro light-emitting structure embodiment, thereby avoiding the first substrate 116 and the buffer layer 117 from blocking the light emitted by the first light-emitting layer 112 and the second light-emitting layer 123, so as to improve the light emission efficiency of the micro light-emitting device 1.

[0080] Specifically, such asFigures 5 to 7 As shown, the first light emitting unit 100A can further include a passivation layer 100A1 covering the micro light emitting structure 10 in the first light emitting unit 100A to protect the micro light emitting structure 10 in the first light emitting unit 100A, thereby improving the reliability of the micro light emitting device 1.

[0081] Exemplarily, the material of the passivation layer 100A1 can include at least one of silicon oxide, silicon nitride, and aluminum oxide, etc.

[0082] In some embodiments, as Figures 5 to 7 As shown, the micro light emitting device 1 can further include a second light emitting unit 100B including the micro light emitting structure 10 of any of the above embodiments and a color conversion layer 100B2. In the second light emitting unit 100B, the micro light emitting structure 10 of the second light emitting unit 100B is bonded to the driving substrate 200 through the first electrode T1 and the second electrode T2, the fourth semiconductor layer 124 of the micro light emitting structure 10 of the second light emitting unit 100B is electrically connected or not electrically connected to the driving substrate 200, and the color conversion layer 100B2 covers the micro light emitting structure 10 of the second light emitting unit 100B and is configured to convert the light emitted by the first light emitting layer 112 into light of a target color, the target color being different from the light emitting colors of the first light emitting layer 112 and the second light emitting layer 123, and the light of the target color, the light reflected by the first light emitting layer 112, and the light emitted by the second light emitting layer 123 can be used to synthesize white light. Specifically, the target color, the light emitting color of the first light emitting layer 112, and the light emitting color of the second light emitting layer 123 can collectively constitute three primary colors to realize full-color display of the micro light emitting device 1.

[0083] Exemplarily, the light emitting color of the first light emitting layer 112 can be blue, the light emitting color of the second light emitting layer 123 can be green, and the target color can be red, thereby realizing red-green-blue three-color display of the micro light emitting device 1. Specifically, the material of the color conversion layer 100B2 can be red quantum dots to realize conversion of blue light emitted by the first light emitting layer 112 into red light by the color conversion layer 100B2.

[0084] Specifically, as Figures 5 to 7As shown, the second light emitting unit 100B can further include a light blocking layer 100B3. In the second light emitting unit 100B, the light blocking layer 100B3 covers the micro light emitting structure 10 of the second light emitting unit 100B, and the light blocking layer 100B3 is provided with an opening 100B4, which is located on the side of the micro light emitting structure 10 of the second light emitting unit 100B away from the driving substrate 200 and penetrates through the light blocking layer 100B3, and the color conversion layer 101 fills the opening 103. In this way, the light emitted by the first light emitting layer 112 of the micro light emitting structure 10 of the second light emitting unit 100B and propagating into the opening 100B4 can be converted into light of the target color by the color conversion layer 100B2, and the light emitted by the first light emitting layer 112 and propagating to the other areas of the light blocking layer 100B3 except the area where the opening 100B4 is located cannot pass through the light blocking layer 100B3, so as to ensure that the second light emitting unit 100B only provides light of the target color.

[0085] Exemplarily, as Figures 5 to 7 shown, the color conversion layer 100B2 can be filled in the opening 100B4, and the light blocking layer 100B3 can be a black matrix.

[0086] Specifically, as Figures 5 to 7 shown, in the second light emitting unit 100B, the outermost layer of the micro light emitting structure 10 of the second light emitting unit 100B away from the driving substrate 200 can be the first semiconductor layer 111, that is, the micro light emitting structure 10 of the second light emitting unit 100B can not include the first substrate 116 and the buffer layer 117 in the above-mentioned embodiment of the micro light emitting structure, so as to avoid the blocking of the first light emitting layer 112 by the first substrate 116 and the buffer layer 117 to the light emitted by the first light emitting layer 112, thereby improving the light extraction efficiency of the micro light emitting device 1.

[0087] Specifically, as Figure 8 shown, the second light emitting unit 100B can further include a passivation layer 100B1, which covers the micro light emitting structure 10 in the second light emitting unit 100B to protect the micro light emitting structure 10 in the second light emitting unit 100B, thereby improving the reliability of the micro light emitting device 1.

[0088] Exemplarily, the material of the passivation layer 100B1 can be at least one of silicon oxide, silicon nitride, aluminum oxide and other insulating materials.

[0089] In other embodiments, as Figures 5 to 8As shown, the micro light emitting device 1 can further include a third light emitting unit 100C bonded with the driving substrate 200, the light emitting color of the third light emitting unit 100C can be different from the light emitting colors of the first light emitting layer 112 and the second light emitting layer 123, and the light emitted by the third light emitting unit 100C, the light reflected by the first light emitting layer 112 and the light emitted by the second light emitting layer 123 can be used to synthesize white light. Specifically, the light emitting color of the third light emitting unit 100C, the light emitting color of the first light emitting layer 112 and the light emitting color of the second light emitting layer 123 can collectively constitute three primary colors to realize full-color display of the micro light emitting device 1.

[0090] Exemplarily, the light emitting color of the first light emitting layer 112 can be blue, the light emitting color of the second light emitting layer 123 can be green, and the light emitting color of the third light emitting unit 100C can be red, so that red, green and blue three-color display of the micro light emitting device 1 can be realized. Specifically, the third light emitting unit 100C can be a red light LED chip, for example, specifically can be a red light Micro-LED chip.

[0091] In the above embodiment, as Figures 5 to 8 shown, the driving substrate 200 can include a second substrate 201, a driving circuit 202, a first driving electrode 203A, a second driving electrode 203B and a third driving unit 203C, wherein the driving circuit 202 is arranged on one side of the second substrate 201, and the first driving electrode 203A, the second driving electrode 203B and the third driving unit 203C are arranged on the same side of the driving circuit 202 away from the second substrate 201, and are all electrically connected with the driving circuit 202.

[0092] Specifically, as Figures 5 to 8 shown, in the first light emitting unit 100A, the first electrode T1 of the micro light emitting structure 10 in the first light emitting unit 100A can be bonded with the first driving electrode 203A of the driving substrate 200, and the second electrode T2 of the micro light emitting structure 10 in the first light emitting unit 100A can be bonded with the second driving electrode 203B of the driving substrate 200. And in the above embodiment in which the micro light emitting structure 10 in the first light emitting unit 100A includes a third electrode T3, as Figures 5 to 7 shown, the third electrode T3 of the micro light emitting structure 10 in the first light emitting unit 100A can be bonded with the third driving electrode 203C of the driving substrate 200 to realize electrical connection between the fourth semiconductor layer 124 of the micro light emitting structure 10 in the first light emitting unit 100A and the driving substrate 200.

[0093] Specifically, in the above embodiment in which the micro light emitting device 1 further includes a second light emitting unit 100B, asFigure 5 As shown, the first electrode T1 of the micro light emitting structure 10 in the second light emitting unit 100B can be bonded with the first driving electrode 203A of the driving substrate 200 correspondingly, and the second electrode T2 of the micro light emitting structure 10 in the second light emitting unit 100B can be bonded with the second driving electrode 203B of the driving substrate 200 correspondingly.

[0094] In some embodiments, as shown in Figure 6 and Figure 5 the micro light emitting structure 10 in the second light emitting unit 100B can include the third electrode T3 in the above-mentioned micro light emitting structure embodiments. And, as shown in Figure 6 the third electrode T3 of the micro light emitting structure 10 in the second light emitting unit 100B can be bonded with the third driving electrode 203C of the driving substrate 200 correspondingly to realize the electrical connection between the fourth semiconductor layer 124 of the micro light emitting structure 10 in the second light emitting unit 100B and the driving substrate 200; or, as shown in Figure 7 the third electrode T3 of the micro light emitting structure 10 in the second light emitting unit 100B can also not be bonded with the third driving electrode 203C of the driving substrate 200 to realize the non-electrical connection between the fourth semiconductor layer 124 of the micro light emitting structure 10 in the second light emitting unit 100B and the driving substrate 200. In this way, for the second light emitting unit 100B, the first electrode T1 and the second electrode T2 of the micro light emitting structure 10 can be provided with corresponding driving signals (such as driving voltage) by the driving substrate 200 respectively, and the third electrode T3 is not provided with corresponding driving signal, so as to realize the light emission of only the first light emitting layer 112 of the micro light emitting structure 10 without the light emission of the second light emitting layer 123, thus realizing the light emission of only one color by the micro light emitting structure 10 in the second light emitting unit 100B, and the light of this color can be converted into light of target color by the color conversion layer 100B2 to ensure the full-color display.

[0095] In other embodiments, as shown in Figure 8 the micro light emitting structure 10 in the second light emitting unit 100B can also not include the third electrode T3 in the above-mentioned micro light emitting structure embodiments, and the fourth semiconductor layer 124 of the micro light emitting structure 10 in the second light emitting unit 100B is not electrically connected with the driving substrate 200 to realize that the driving substrate 200 can only drive the light emission of the first light emitting layer 112 of the micro light emitting structure 10 without the light emission of the second light emitting layer 123, thus realizing the light emission of only one color by the micro light emitting structure 10 in the second light emitting unit 100B, and the light of this color can be converted into light of target color by the color conversion layer 100B2 to ensure the full-color display.

[0096] Specifically, in the above-mentioned embodiment in which the micro light emitting device 1 further comprises a third light emitting unit 100C, as shown in ​ The driving substrate 200 can further comprise a fourth driving electrode 203D and a fifth driving unit 203F, which are arranged on the same side of the driving circuit 202 as the first driving electrode 203A, the second driving electrode 203B and the third driving unit 203C, and are both electrically connected to the driving circuit 202. Moreover, the two electrodes of the third light emitting unit 100C can be respectively bonded in correspondence with the fourth driving electrode 203D and the fifth driving unit 203F of the driving substrate 200, so that the driving substrate 200 can provide corresponding driving signals (such as driving voltage) to the third light emitting unit 100C to drive the third light emitting unit 100C to emit light and realize full-color display.

[0097] In some embodiments, the micro light emitting device 1 can further comprise at least one microlens (not shown in the figure), which is arranged on the light emitting side of the first light emitting unit 100A and the second light emitting unit 100B, or on the light emitting side of the first light emitting unit 100A and the third light emitting unit 100C, and each microlens in the at least one microlens can be used to improve the light emitting efficiency of its corresponding first light emitting unit 100A, second light emitting unit 100B or third light emitting unit 100C.

[0098] Exemplarily, the microlens can be a convex lens.

[0099] In some examples, the material of the first driving electrode 203A can include conductive materials such as titanium (Ti), aluminum (Al), gold (Au), platinum (Pt) and / or nickel (Ni). The material of the second driving electrode 203B can include conductive materials such as titanium (Ti), aluminum (Al), gold (Au), platinum (Pt) and / or nickel (Ni). The material of the third driving electrode 203C can include conductive materials such as titanium (Ti), aluminum (Al), gold (Au), platinum (Pt) and / or nickel (Ni). Moreover, in specific implementation, the first driving electrode 203A, the second driving electrode 203B and the third driving electrode 203C can have the same material and can be formed synchronously.

[0100] In some examples, the driving substrate 200 can be a driving chip or a driving wafer.

[0101] In some examples, the micro light emitting device 1 described above can not only be applied to the projection part of electronic devices such as optical projection, vehicle head-up display (HUD), etc., but also can be applied to the display part of electronic devices, for example, the electronic devices can include any device with a display screen such as a smart phone, a smart watch, a notebook computer, a tablet computer, a driving recorder, a navigator, a head-mounted device, etc., and can also be applied to the lighting part of electronic devices, for example, the electronic devices can include any device with a lighting component such as a vehicle, a street lamp, etc.

[0102] It should be noted that the micro light emitting device provided by the embodiments of the present application can realize the beneficial effects of any one of the micro light emitting structures provided by the embodiments of the present application due to the micro light emitting structure provided by the embodiments of the present application. Details are described in the foregoing embodiments, which will not be repeated here.

[0103] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The features, structures or characteristics described above can be combined in any suitable manner in one or more embodiments.

[0104] The above only describes the preferred embodiments of the present application and does not limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A micro-luminescent structure, characterized in that, include: A first light-emitting structure and a second light-emitting structure are connected and arranged opposite to each other by a bonding layer. The first light-emitting structure includes a first semiconductor layer, a first light-emitting layer and a second semiconductor layer stacked sequentially. The bonding layer is disposed on the side of the second semiconductor layer away from the first light-emitting layer. The second light-emitting structure includes a third semiconductor layer, a second light-emitting layer and a fourth semiconductor layer stacked sequentially on the side of the bonding layer away from the second semiconductor layer. The third semiconductor layer and the second semiconductor layer are electrically connected through the bonding layer. The third semiconductor layer and the second semiconductor layer have the same polarity. The fourth semiconductor layer and the first semiconductor layer have the same polarity. The first semiconductor layer and the second semiconductor layer have different polarities. The first light-emitting layer and the second light-emitting layer have different light-emitting colors. A first groove and a second groove, wherein the first groove extends from the surface of the second light-emitting structure opposite to the first light-emitting structure to the bonding layer, and the second groove extends from the surface of the second light-emitting structure opposite to the first light-emitting structure to the first semiconductor layer; The first electrode is disposed on the bottom wall surface of the first groove, and the second electrode is disposed on the bottom wall surface of the second groove. Both the first electrode and the second electrode protrude at least partially from the side of the fourth semiconductor layer away from the second light-emitting layer.

2. The micro-light-emitting structure according to claim 1, characterized in that, The micro-light-emitting structure further includes a third electrode, which is disposed on the side of the fourth semiconductor layer away from the second light-emitting layer, and the third electrode at least partially protrudes and is exposed on the side of the fourth semiconductor layer away from the second light-emitting layer.

3. The micro-light-emitting structure according to claim 2, characterized in that, The first electrode includes a first raised electrode and a first bonding electrode stacked sequentially on the bottom wall surface of the first groove. The second electrode includes a second raised electrode and a second bonding electrode stacked sequentially on the bottom wall surface of the second groove. The first bonding electrode, the second bonding electrode, and the third electrode are at the same height relative to the plane containing the bottom wall surface of the second groove. The first raised electrode and the second raised electrode are at the same height relative to the plane containing the bottom wall surface of the second groove.

4. The micro-light-emitting structure according to claim 2, characterized in that, The micro-luminescent structure also includes: A passivation layer covers the inner wall surface of the first groove, the inner wall surface of the second groove, the first light-emitting structure, and the second light-emitting structure, and the first electrode, the second electrode, and the third electrode all penetrate the passivation layer.

5. The micro-light-emitting structure according to claim 1, characterized in that, The bonding layer includes a first bonding layer and a second bonding layer sequentially stacked on the side of the second semiconductor layer away from the first light-emitting layer. The first bonding layer has a first light-transmitting area, the second bonding layer has a second light-transmitting area, and the orthographic projection of the second light-transmitting area on the first bonding layer at least partially overlaps with the first light-transmitting area. The light emitted by the second light-emitting layer passes through the second light-transmitting area and the first light-transmitting area in sequence before being emitted.

6. The micro-light-emitting structure according to claim 5, characterized in that, The first light-transmitting area has a first opening that penetrates the first bonding layer, and the second light-transmitting area has a second opening that penetrates the second bonding layer, and the first opening and the second opening are connected.

7. A miniature light-emitting device, characterized in that, The device includes a first light-emitting unit and a driving substrate. The first light-emitting unit includes a micro light-emitting structure as described in any one of claims 1 to 6. In the first light-emitting unit, the micro light-emitting structure of the first light-emitting unit is bonded to the driving substrate through the first electrode and the second electrode. The fourth semiconductor layer of the micro light-emitting structure of the first light-emitting unit is electrically connected to the driving substrate.

8. The micro light-emitting device according to claim 7, characterized in that, The micro light-emitting device further includes a third light-emitting unit, which is bonded to the driving substrate, and the light reflected by the third light-emitting unit, the light reflected by the first light-emitting layer, and the light reflected by the second light-emitting layer are used to synthesize white light.

9. A miniature light-emitting device, characterized in that, The device includes a first light-emitting unit, a second light-emitting unit, and a driving substrate. The first light-emitting unit includes a micro-light-emitting structure as described in any one of claims 1 to 6. In the first light-emitting unit, the micro-light-emitting structure of the first light-emitting unit is bonded to the driving substrate through the first electrode and the second electrode. The fourth semiconductor layer of the micro-light-emitting structure of the first light-emitting unit is electrically connected to the driving substrate. The second light-emitting unit includes the micro-light-emitting structure as described in any one of claims 1 to 6 and a color conversion layer. In the second light-emitting unit, the micro-light-emitting structure of the second light-emitting unit is bonded to the driving substrate through the first electrode and the second electrode. The color conversion layer covers the micro-light-emitting structure of the second light-emitting unit and is configured to convert the light emitted by the first light-emitting layer into light of a target color. The light of the target color, the light reflected by the first light-emitting layer, and the light emitted by the second light-emitting layer are used to synthesize white light.

10. The micro light-emitting device according to claim 9, characterized in that, The second light-emitting unit further includes a light-blocking layer, and in the second light-emitting unit, the light-blocking layer covers the micro light-emitting structure of the second light-emitting unit, and the light-blocking layer has an opening located on the side of the micro light-emitting structure of the second light-emitting unit away from the driving substrate and penetrating the light-blocking layer, and the color conversion layer fills the opening.

Images