Miniature light-emitting diode chip, miniature light-emitting diode device and display device

Abstract

The utility model provides a miniature light-emitting diode chip, a miniature light-emitting diode device and a display device, the miniature light-emitting diode chip comprises an epitaxial layer, a substrate, a first micro-channel network and a first heat conduction structure, the substrate comprises a first surface and a second surface which are oppositely arranged, and the epitaxial layer is arranged on the first surface; the first micro-channel network is arranged on the substrate, and the minimum distance between the first micro-channel network and the first surface is smaller than the minimum distance between the first micro-channel network and the second surface; the first heat conduction structure is arranged in the first micro-channel network. On the basis, the micro light-emitting diode chip has better heat dissipation performance, and can be better applied to electronic equipment with high performance requirements and compact internal space, such as a mobile phone, a notebook computer and the like.

Description

TECHNICAL FIELD

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

[0002] Micro-LED (Micro-Light Emitting Diode) display technology is a display technology that microstructures and arrays traditional LED (Light Emitting Diode) structures, and uses CMOS (Complementary Metal Oxide Semiconductor) or TFT (Thin Film Transistor) to make driving circuit to realize addressing control and individual driving of each pixel structure.

[0003] The Micro-LED device of the related art has the problem of poor display effect when applied to electronic devices such as mobile phones and tablet computers. CONTENT OF THE INVENTION

[0004] The present application aims to provide a micro light emitting diode chip, a micro light emitting diode device and a display device.

[0005] In order to solve the above problems, in a first aspect, the present application provides a micro light emitting diode chip, comprising:

[0006] an epitaxial layer;

[0007] a substrate comprising a first surface and a second surface arranged oppositely, the epitaxial layer being arranged on the first surface;

[0008] a first micro-channel network arranged in the substrate, the minimum distance between the first micro-channel network and the first surface being smaller than the minimum distance between the first micro-channel network and the second surface; and

[0009] a first heat conduction structure arranged in the first micro-channel network.

[0010] Optionally, the first micro-channel network comprises a fractal dendrite structure or a reticular structure.

[0011] Optionally, the first heat conduction structure comprises a liquid metal structure or a graphene-based nanofluid structure.

[0012] Optionally, the first heat conduction structure comprises a gallium-based alloy structure.

[0013] Optionally, the epitaxial layer comprises, in sequence, a buffer layer, a first semiconductor layer, a light-emitting layer, and a second semiconductor layer on the first surface; and the micro LED chip further comprises:

[0014] a second microfluidic network disposed on the buffer layer; and

[0015] a second heat-conducting structure disposed in the second microfluidic network.

[0016] Optionally, the micro LED chip further comprises:

[0017] a self-repairing structure disposed on the substrate and attached to the first surface.

[0018] Optionally, a projection of the self-repairing structure on the first surface covers the entire first surface, or a projection of the self-repairing structure on the first surface covers part of the first surface.

[0019] Optionally, the first microfluidic network and the self-repairing structure are both disposed inside the substrate, the self-repairing structure is disposed between the first heat-conducting structure and the first surface, and a projection of the self-repairing structure and the first heat-conducting structure on the first surface coincides.

[0020] Optionally, the self-repairing structure comprises a furan / maleimide dynamic covalent polymer structure.

[0021] In a second aspect, the present application also provides a micro LED device, comprising:

[0022] a driving chip; and

[0023] a micro LED chip as described above, which is electrically connected to the driving chip.

[0024] In a third aspect, the present application also provides a display device comprising a micro LED device as described above.

[0025] Based on the technical scheme, the micro light emitting diode chip, the micro light emitting diode device and the display device provided by the application have the advantages that the minimum distance between the first micro channel network of the micro light emitting diode chip and the first surface is smaller than the minimum distance between the first micro channel network and the second surface, the first micro channel network is closer to the first surface of the substrate and the epitaxial layer, when the first heat conduction structure is arranged in the first micro channel network, the first heat conduction structure is also closer to the epitaxial layer, the first heat conduction structure can improve the heat conduction inside the micro light emitting diode chip and avoid local overheating, and the first heat conduction structure can also conduct the heat generated by the epitaxial layer during operation to the outside of the chip and realize the heat dissipation of the micro light emitting diode chip, so that the micro light emitting diode chip has better heat dissipation performance, and the micro light emitting diode chip can be better applied to electronic devices such as mobile phones and notebook computers which have high performance requirements and compact internal space.

[0026] In addition, when the first micro channel network of the application adopts a nano confinement design, the thermal conductivity of the first heat conduction structure in the nano confinement state is significantly improved, further improving the heat dissipation performance of the micro light emitting diode chip. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can also be obtained according to these drawings without creative labor for those skilled in the art.

[0028] In order to more completely understand the application and its beneficial effects, the following will be described in conjunction with the drawings, wherein the same reference numerals in the following description represent the same parts.

[0029] Figure 1 The first structure schematic diagram of the micro light emitting diode chip provided by the embodiment of the application;

[0030] Figure 2 The second structure schematic diagram of the micro light emitting diode chip provided by the embodiment of the application;

[0031] Figure 3 The third structure schematic diagram of the micro light emitting diode chip provided by the embodiment of the application;

[0032] Figure 4 The fourth structure schematic diagram of the micro light emitting diode chip provided by the embodiment of the application;

[0033] Figure 5 The structure schematic diagram of the micro light emitting diode device provided by the embodiment of the application;

[0034] Figure 6A structural schematic diagram of a display device provided by an embodiment of the present application 。

[0035] Reference signs are indicated as:

[0036] 10, display device; 20, micro light emitting diode device; 100, micro light emitting diode chip; 200, driving chip; 110, substrate; 120, epitaxial layer; 130, first micro channel network; 140, first heat conduction structure; 150, second micro channel network; 160, second heat conduction structure; 170, self-repairing structure; 111, first surface; 112, second surface; 121, buffer layer; 122, first semiconductor layer; 123, light emitting layer; 124, second semiconductor layer; 125, first electrode layer; 126, second electrode layer; 127, solder structure; 128, passivation layer. DETAILED DESCRIPTION

[0037] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments of the present application and, together with the description, further serve to explain the principles of the application and to enable a person skilled in the relevant art(s) to make and use the application. Figure 1 to the drawings Figure 6 and embodiments, the technical solutions in the present application will be apparently and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by a person skilled in the art without creative effort, fall within the protection scope of the present application.

[0038] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. A person skilled in the art will understand that the embodiments described herein can be combined with one another.

[0039] With the continuous development of Micro-LED display technology, it gradually develops in the direction of small size and high resolution. The monolithic integrated Micro-LED chip has the advantages of high brightness, low power consumption, excellent color performance, fast response speed, strong reliability, etc. when applied to electronic devices such as mobile phones, tablet computers, etc. However, the monolithic integrated Micro-LED chip also faces some difficulties in mobile phone applications, for example, the junction temperature of the light emitting layer (such as gallium nitride GaN layer) of the Micro-LED chip can reach 80-100℃ when working, which exceeds the safety temperature threshold of the CPU and battery of the mobile phone; for another example, the silicon substrate (CTE≈2.6×10 -6 / K) of the Micro-LED chip and the GaN epitaxial layer (CTE≈5.6×10 -6The thermal expansion difference of the materials of the Micro-LED chip and the substrate causes the Micro-LED chip to warp, pixel shift and other problems at high temperature, which affects the display effect of the Micro-LED chip and the reliability of the Micro-LED device.

[0040] To solve the above technical problems, the present application provides a micro light emitting diode chip 100, a micro light emitting diode device 20 and a display device 10. The following will be described in detail in combination with specific embodiments. It should be noted that the embodiments of the present application can be presented in various forms, and some examples will be described below.

[0041] Please refer to Figure 1 , Figure 1 The micro light emitting diode chip 100 provided by the embodiments of the present application has a structure diagram as shown in the figure. The micro light emitting diode chip 100 includes a substrate 110, an epitaxial layer 120, a first micro channel network 130 and a first heat conduction structure 140.

[0042] The substrate 110 includes a first surface 111 and a second surface 112 arranged oppositely, and the epitaxial layer 120 is arranged on the first surface 111 of the substrate 110. The first micro channel network 130 is arranged on the substrate 110, and the minimum distance between the first micro channel network 130 and the first surface 111 of the substrate 110 is smaller than the minimum distance between the first micro channel network 130 and the second surface 112 of the substrate 110, and the first micro channel network 130 is closer to the epitaxial layer 120. The first heat conduction structure 140 is arranged in the first micro channel network 130, and the first heat conduction structure 140 is used to conduct the heat generated by the epitaxial layer 120 when working to the outside of the micro light emitting diode chip 100.

[0043] It can be understood that the substrate 110 is used to support the epitaxial layer 120 thereon, and also used to carry the first micro channel network 130 and the first heat conduction structure 140. The substrate 110 can be but not limited to a sapphire substrate, a silicon substrate or a silicon carbide substrate, etc.

[0044] It can be understood that the first micro channel network 130 is used to guide and limit the flow of the first heat conduction structure 140. In some examples, the first micro channel network 130 is arranged inside the substrate 110. In other examples, the first micro channel network 130 is arranged on the surface of the substrate 110, for example, the first micro channel network 130 is arranged on the first surface 111 of the substrate 110. In some examples, the first micro channel network 130 adopts a nano confinement design, and a micro or even nano channel network for guiding and controlling fluid flow is arranged inside or on the surface of the substrate 110. In the nano confinement state, the heat conduction performance of the first heat conduction structure 140 will change significantly, and theoretically the thermal conductivity of the first heat conduction structure 140 can reach several times of that in the macro state, greatly improving the heat dissipation performance of the first heat conduction structure 140.

[0045] It can be understood that the first heat-conducting structure 140 has excellent heat-conducting property. When the first heat-conducting structure 140 is arranged in the first micro-channel network 130, the first heat-conducting structure 140 is closer to the epitaxial layer 120, and the first heat-conducting structure 140 can more quickly conduct the heat generated by the epitaxial layer 120 to the outside of the chip and achieve heat dissipation to the outside, and the first heat-conducting structure 140 can exchange heat with the structure outside the micro light-emitting diode chip 100. For example, when the micro light-emitting diode chip 100 is arranged in a mobile phone, a notebook computer or other electronic device, the first heat-conducting structure 140 can conduct the heat generated by the epitaxial layer 120 to the outside of the micro light-emitting diode chip 100 through an interface at which the micro light-emitting diode chip 100 is connected to other structures of the electronic device, so as to exchange heat with the structure outside the micro light-emitting diode chip 100.

[0046] It can be understood that the first heat-conducting structure 140 can be, but is not limited to, water, oil, alcohol, a metal structure, a phase-change material structure, a nanofluid structure, a thermoelectric material structure, etc.

[0047] In the micro light-emitting diode chip 100 of the embodiment, the minimum distance between the first micro-channel network 130 and the first surface 111 is smaller than the minimum distance between the first micro-channel network 130 and the second surface 112, and the first micro-channel network 130 is closer to the first surface 111 of the substrate 110 and the epitaxial layer 120. When the first heat-conducting structure 140 is arranged in the first micro-channel network 130, the first heat-conducting structure 140 is also closer to the epitaxial layer 120. On the one hand, the first heat-conducting structure 140 can improve the heat conduction performance inside the micro light-emitting diode chip 100, thereby avoiding local overheating of the chip. On the other hand, the first heat-conducting structure 140 can timely and quickly conduct the heat generated by the epitaxial layer 120 during operation to the outside of the chip and achieve heat dissipation of the micro light-emitting diode chip 100 to the outside, so that the micro light-emitting diode chip 100 of the application has better heat dissipation performance, and the micro light-emitting diode chip 100 can be better applied to mobile phones, notebook computers and other electronic devices with high performance requirements and compact internal space. Moreover, when the first micro-channel network 130 of the embodiment adopts a nanometer limited design, the heat conductivity of the first heat-conducting structure 140 in the nanometer limited state is significantly improved, further improving the heat dissipation performance of the micro light-emitting diode chip 100.

[0048] In some examples, the first microfluid network 130 adopts a nano-restricted design, and the surface roughness Ra of the first microfluid network 130 is less than 50 nm, for example, the surface roughness Ra of the first microfluid network 130 is about 40 nm, 30 nm, 20 nm or 10 nm. The surface roughness Ra of the first microfluid network 130 of the embodiment of the present application is less than 50 nm, and the first microfluid network 130 can restrict the flow of the liquid or semi-liquid first heat-conductive structure 140. The first microfluid network 130 and the first heat-conductive structure 140 are not prone to collapse.

[0049] In some examples, the first heat-conductive structure 140 includes a liquid metal structure. The liquid metal structure is a metal substance in a liquid state at room temperature or under specific conditions, has the characteristics of metals such as good electrical conductivity and thermal conductivity, and has the flowability of a liquid. The liquid metal structure also has unique physical and chemical properties, such as high surface tension and low volatility. The liquid metal structure can absorb thermal stress through plastic deformation, thereby achieving heat dissipation of the micro light-emitting diode chip 100.

[0050] In some examples, the liquid metal structure of the first heat-conductive structure 140 can include, but is not limited to, a gallium-based alloy structure, for example, including Ga 50 In 30 Sn 20 structure (melting point 55℃). The gallium-based alloy structure is in a solid state at room temperature when the micro light-emitting diode chip 100 is not working, and is in a semi-solid state at the working temperature (80℃ to 100℃) of the micro light-emitting diode chip 100. The gallium-based alloy structure absorbs thermal stress (energy density > 3 J / cm 3 , thermal conductivity 32 W / (m·K), flow resistance <10 -2 Pa·s). The embodiment of the present application fills the high-melting-point gallium-based alloy structure in the nano-restricted first microfluid network 130. The gallium-based alloy structure has good heat dissipation, and at the same time, the gallium-based alloy structure is in a solid state at room temperature, which can enhance the structural strength of the micro light-emitting diode chip 100 and avoid collapse of the first microfluid network 130.

[0051] In some examples, the first heat-conductive structure 140 includes a graphene-based nanofluid structure. The graphene-based nanofluid structure is a nanofluid with graphene nanosheets as the dispersed phase and water, ethylene glycol or other liquids as the base liquid. The graphene-based nanofluid structure has good thermal conductivity, electrical conductivity, high strength and large specific surface area. The thermal conductivity of the graphene-based nanofluid structure of the embodiment of the present application can reach 5000 W / m·K or more, the flowability is excellent, the chemical inertness is strong, the graphene-based nanofluid structure has excellent heat dissipation performance, and is not prone to physical or chemical reactions with other structures, thereby improving the stability of the micro light-emitting diode chip 100.

[0052] In some examples, the first microfluidic network 130 includes a fractal dendritic structure. A fractal dendritic structure is formed in a recursive manner, with a main branch microfluidic channel including a plurality of branch microfluidic channels, each branch microfluidic channel further splitting into a plurality of smaller secondary branch microfluidic channels, thereby forming a hierarchical microfluidic network. It can be appreciated that the angle and proportion of the branches can be kept consistent in each level of branch microfluidic channels of the first microfluidic network 130, forming a self-similar geometric feature. In some examples, the first microfluidic network 130 has symmetry, with the branch structure on the left side being a mirror image of the branch structure on the right side, and the first microfluidic network 130 can form a balanced fluid distribution. The first microfluidic network 130 of the embodiments of the present application includes a fractal dendritic structure, the first microfluidic network 130 has a plurality of branches, and the first microfluidic network 130 can uniformly distribute the stress generated by the substrate 110 under temperature change, thereby reducing the adverse effects of stress on the substrate 110.

[0053] In some examples, the first microfluidic network 130 includes a mesh structure. A mesh structure includes a plurality of microfluidic structures that are interconnected in a grid form, with a plurality of levels of branches and intersections, and fluid can flow in multiple directions and paths. In some examples, the mesh structure is mirror-symmetrical, such that the first microfluidic network 130 has symmetry, and the first microfluidic network 130 can form a balanced fluid distribution. The first microfluidic network 130 of the embodiments of the present application is a mesh structure, the first microfluidic network 130 has a plurality of interconnected channels, and the first microfluidic network 130 can uniformly distribute the stress generated by the substrate 110 under temperature change, thereby reducing the adverse effects of stress on the substrate 110.

[0054] In some examples, please refer to Figure 1 and please refer to Figure 2 , Figure 2 A second structural schematic diagram of the micro light emitting diode chip 100 provided by the embodiments of the present application. The epitaxial layer 120 includes a buffer layer 121, a first semiconductor layer 122, a light emitting layer 123, and a second semiconductor layer 124, which are sequentially stacked on the first surface 111. The micro light emitting diode chip 100 further includes a second microfluidic network 150 and a second heat conduction structure 160, the second microfluidic network 150 is arranged in the buffer layer 121, and the second heat conduction structure 160 is arranged in the second microfluidic network 150.

[0055] It can be understood that the buffer layer 121 can relieve the stress between the film layer and the substrate 110 due to the lattice mismatch and the mismatch of the thermal expansion coefficient. The buffer layer 121 can be, but is not limited to, a silicon nitride layer, a silicon oxide layer, a gallium nitride layer, or an aluminum nitride layer. The light-emitting layer 123 is a quantum well layer, for example, the light-emitting layer 123 is an indium gallium nitride quantum well layer or an indium gallium nitride / gallium nitride multi-quantum well layer. The first semiconductor layer 122 is one of an N-type semiconductor layer and a P-type semiconductor layer, and the second semiconductor layer 124 is the other of the N-type semiconductor layer and the P-type semiconductor layer. The N-type semiconductor layer is an N-type gallium nitride layer or an N-type gallium arsenide layer, and the P-type semiconductor layer is a P-type gallium nitride layer or a P-type aluminum gallium nitride layer.

[0056] It can be understood that the second micro-channel network 150 is used to guide and limit the flow of the second heat-conducting structure 160. In some examples, the second micro-channel network 150 is arranged inside the buffer layer 121. In other examples, the second micro-channel network 150 is arranged on the surface of the buffer layer 121, for example, the second micro-channel network 150 is arranged on the surface of the buffer layer 121 that is in contact with the substrate 110. In some examples, the second micro-channel network 150 adopts a nano-confined design, and the surface roughness Ra of the second micro-channel network 150 is less than 50 nm. In some examples, the second micro-channel network 150 includes a fractal dendritic structure or a network structure. It should be noted that the structure of the second micro-channel network 150 can be the same as the second micro-channel network 150.

[0057] It can be understood that the second heat-conducting structure 160 has excellent heat conductivity. The second heat-conducting structure 160 can conduct the heat generated by the epitaxial layer 120 to the outside of the chip, which can not only avoid local overheating of the micro light-emitting diode chip 100, but also achieve external heat dissipation. In some examples, the second heat-conducting structure 160 includes a liquid metal structure, for example, the second heat-conducting structure 160 can include, but is not limited to, a gallium-based alloy structure. In other examples, the second heat-conducting structure 160 includes a graphene-based nanofluid structure. It should be noted that the second heat-conducting structure 160 can be the same as the first heat-conducting structure 140.

[0058] It can be understood that in some examples, the second micro-channel network 150 is arranged in the region of the buffer layer 121 close to the substrate 110, that is, the minimum distance between the second micro-channel network 150 and the first surface 111 of the substrate 110 is less than the minimum distance between the second micro-channel network 150 and the first semiconductor layer 122. At this time, the second heat-conducting structure 160 is closer to the substrate 110, and the influence of the second heat-conducting structure 160 on the first semiconductor layer 122 is smaller.

[0059] The second micro-channel network 150 and the second heat conduction structure 160 are arranged in the buffer layer 121, the second heat conduction structure 160 can dissipate the heat generated by the first semiconductor layer 122, the light-emitting layer 123 and the second semiconductor layer 124 received by the buffer layer 121, and further improve the heat dissipation performance of the micro light-emitting diode chip 100.

[0060] In some examples, please refer to Figure 1 and please refer to Figure 3 , Figure 3 The third structure schematic diagram of the micro light-emitting diode chip 100 provided by the embodiments of the present application is shown. The micro light-emitting diode chip 100 further comprises a self-repairing structure 170. The self-repairing structure 170 is arranged in the substrate 110, and the self-repairing structure 170 is attached to the first surface 111.

[0061] It can be understood that the self-repairing structure 170 refers to a structure with self-repairing ability, which can automatically repair when damaged or destroyed, and restore its integrity and function. The self-repairing structure 170 can include, but is not limited to, a microcapsule structure, a microchannel structure, a shape memory material structure, etc. The self-repairing structure 170 releases a repair agent or realizes automatic repair through the shape memory effect of the material when damage occurs.

[0062] It can be understood that in some examples, the self-repairing structure 170 is arranged in the substrate 110 and attached to the first surface 111. In other examples, the self-repairing structure 170 is arranged on the first surface of the substrate 110, and the self-repairing structure 170 is attached to the interface between the substrate 110 and the epitaxial layer 120. When the high temperature generated during the operation of the micro light-emitting diode chip 100 causes a large difference in thermal expansion between the substrate 110 and the epitaxial layer 120 thereon, the self-repairing structure 170 will expand with the substrate 110 and be damaged, and then the self-repairing structure 170 can automatically repair.

[0063] The self-repairing structure 170 of the embodiments of the present application can automatically repair micro cracks and restore its integrity and function when the substrate 110 and the epitaxial layer 120 thereon of the micro light-emitting diode chip 100 are warped due to a large difference in thermal expansion. The self-repairing structure 170 can reduce or avoid the warping phenomenon of the micro light-emitting diode chip 100, thereby ensuring the display effect and reliability of the micro light-emitting diode chip 100.

[0064] In some examples, the self-repairing structure 170 includes a furan / maleimide dynamic covalent polymer structure. The self-repairing structure 170 includes a Diels-Alder type dynamic covalent polymer, and 10wt% boron nitride nanosheets (particle size 100 nm, thermal conductivity 300 W / (m·K)) are added to improve the thermal conductivity and mechanical strength. The trigger temperature of the self-repairing structure 170 of the embodiment of the application is about 60°C, and the dynamic covalent bond recombination repairs micro-cracks at 60°C, realizes low-temperature trigger self-repairing, and adapts to the safety temperature threshold of devices such as mobile phones. For example, the self-repairing structure 170 of the embodiment of the application can trigger repair when the mobile phone is charged to 60-70°C, and the user is not aware.

[0065] In some examples, please continue to refer to Figure 3 The projection of the self-repairing structure 170 on the first surface 111 covers part of the first surface 111, and the self-repairing structure 170 is locally arranged on the first surface 111. At this time, the locally arranged self-repairing structure 170 has less effect on the light efficiency of the micro light-emitting diode chip 100 and also has less effect on the heat dissipation (thermal resistance) of the micro light-emitting diode chip 100.

[0066] In some examples, please continue to refer to Figure 3 The self-repairing structure 170 and the first micro-channel network 130 are both arranged inside the substrate 110. In the thickness direction of the micro light-emitting diode chip 100, the self-repairing structure 170 is arranged between the first micro-channel network 130 and the first surface 111, and the projection of the self-repairing structure 170 on the first surface 111 coincides with the projection of the first heat-conducting structure 140 on the first surface 111. At this time, the self-repairing structure 170 and the first heat-conducting structure 140 are stacked and arranged correspondingly. The self-repairing structure 170 is arranged between the first heat-conducting structure 140 and the epitaxial layer 120, and the self-repairing structure 170 can protect the interface between the first heat-conducting structure 140 and the epitaxial layer 120.

[0067] In some examples, please refer to Figure 4 , Figure 4 is a fourth structural schematic diagram of the micro light-emitting diode chip 100 provided by the embodiment of the application. The projection of the self-repairing structure 170 on the first surface 111 covers the entire first surface 111, and the self-repairing structure 170 is arranged on the first surface 111 in a full-surface arrangement. At this time, the self-repairing structure 170 has a larger contact area with the substrate 110 and the epitaxial layer 120, and the self-repairing structure 170 has a larger repair area and better repair performance, which can further reduce or avoid the warping phenomenon of the micro light-emitting diode chip 100.

[0068] The micro light emitting diode chip 100 of the embodiment of the present application, through the synergistic effect of the high-melting-point alloy micro channel and the self-repairing polymer, and through the synergistic effect of the alloy plastic deformation and the self-repairing polymer, realizes efficient thermal stress compensation, solves the thermal expansion mismatch problem of the micro light emitting diode chip 100, improves the reliability of the micro light emitting diode chip 100 and guarantees the display effect, and can be applied to mobile phones and other highly integrated and high-temperature terminal devices.

[0069] Among them, please refer to Figures 1 to 4 In some examples, the epitaxial layer 120 of the micro light emitting diode chip 100 of the embodiment of the present application further includes a first electrode layer 125, a second electrode layer 126, a current diffusion layer (not shown in the figure), a solder structure 127, a passivation layer 128, etc. The first electrode layer 125 is arranged on the side of the second semiconductor layer 124 away from the light emitting layer 123 and is electrically connected with the second semiconductor layer 124. The second electrode layer 126 is arranged on the exposed area of the first semiconductor layer 122 and is electrically connected with the first semiconductor layer 122. The current diffusion layer can uniformly spread the current to the entire first semiconductor layer 122, thereby effectively improving the light emitting efficiency of the micro light emitting diode chip 100. The passivation layer 128 at least covers the outer surfaces of the first semiconductor layer 122, the light emitting layer 123 and the second electrode layer 126 to protect them. The solder structure 127 is connected to the first electrode layer 125 and the second electrode layer 126, and the solder structure 127 can be made of, but is not limited to, indium (In), aluminum (Al), tin (Sn), silver (Ag), gold (Au), gold-tin alloy, nickel-gold alloy, etc. The solder structure 127 is used for bonding connection with the driving chip 200 described below.

[0070] Based on the above description, the present application further provides a micro light emitting diode device 20, please refer to Figure 5 , Figure 5 The structure schematic diagram of the micro light emitting diode device 20 provided by the embodiment of the present application. The micro light emitting diode device 20 includes a driving chip 200 and the micro light emitting diode chip 100 of any of the above embodiments. The micro light emitting diode chip 100 is electrically connected with the driving chip 200, and the driving chip 200 provides driving control to the micro light emitting diode chip 100.

[0071] The driving chip 200 includes a substrate, and a driving circuit and one or more driving pads formed on the substrate. The driving circuit can be, but is not limited to, a CMOS circuit structure or a TFT circuit structure. The driving pads can be, but are not limited to, prepared by metals such as In, Al, Sn, Ag, Au, gold-tin alloy, nickel-gold alloy, etc. The driving chip 200 further includes an electrical connection part electrically connected to the circuit board. The one or more driving pads are used to be arranged and bonded one by one with the one or more pad structures 127 of the micro light emitting diode chip 100, and the driving chip 200 is bonded with the micro light emitting diode chip 100 to form the micro light emitting diode device 20. Since the micro light emitting diode chip 100 of the embodiment of the present application has better heat dissipation performance and low-temperature trigger self-repairing performance, the micro light emitting diode device 20 of the embodiment of the present application can be adapted to the display device 10 of a mobile phone and other highly integrated display devices with high requirements on working temperature.

[0072] Based on the above description, the embodiment of the present application further provides a display device 10, which is described below with reference to Figure 6 , Figure 6 The display device 10 provided by the embodiment of the present application is shown in the structural schematic diagram. The display device 10 can be applied to electronic equipment to realize augmented reality (AR), virtual reality (VR), mixed reality (MR), and other extended reality (XR) technologies. In implementation, the display device 10 can be a projection part of the electronic equipment, such as a projector, a head-up display (HUD), etc. For example, the display device 10 can also be a display part of the electronic equipment, such as a smart phone, a smart watch, a notebook computer, a tablet computer, a driving recorder, a navigator, a head-mounted device, etc. For example, the display device 10 can also be an illumination part of the electronic equipment, such as a vehicle, a street lamp, etc.

[0073] It can be understood that the display device 10 of the embodiment of the present application includes the micro light emitting diode device 20 of any of the above embodiments. Therefore, the display device 10 of the present application has better heat dissipation performance, display performance, and reliability, and can be better applied to a mobile phone and other highly integrated terminals with high requirements on working temperature. It should be noted that the micro light emitting diode device 20 and the display device 10 of the embodiment of the present application are different subjects under the same inventive concept, and features not described in detail in each embodiment can be referred to the description in other embodiments.

[0074] It should be noted that the "multiple" mentioned in the present application generally refers to two or more. Moreover, the direction terms mentioned in the embodiments of the present application, such as "up", "down", "front", "back", "left", "right", "inner", "outer", "side" and the like, are only the directions of the reference drawings. Therefore, the direction terms used are used to illustrate and understand the embodiments of the present application, and are not used to limit the embodiments of the present application. In each of the drawings, similar units are denoted 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 may not be shown in the drawings.

[0075] It should be understood that in the description of the present application, terms such as "first", "second" and the like are only used to distinguish similar objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated.

[0076] It can be understood that those skilled in the art can combine various embodiments in each of the above embodiments under the teaching of the above embodiments to obtain technical solutions of various embodiments. The above description is only the preferred embodiment of the present application and is not used to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

[0077] The micro light emitting diode chip, the micro light emitting diode device and the display device provided by the present application are described in detail above. The principles and implementation manners of the present application are described by applying specific examples in this paper, and the above embodiment descriptions are only used to help understand the present application. At the same time, for those skilled in the art, according to the idea of the present application, the specific implementation manner and application range will be changed, and the above description should not be understood as limiting the present application.

Claims

1. A micro light emitting diode chip, characterized by, The micro light emitting diode chip comprises: an epitaxial layer; a substrate comprising oppositely arranged first and second surfaces, the epitaxial layer being arranged on the first surface; a first microfluidic network arranged on the substrate, the minimum distance between the first microfluidic network and the first surface being smaller than the minimum distance between the first microfluidic network and the second surface; and a first heat conduction structure arranged in the first microfluidic network. The first microfluidic network comprises a fractal dendritic structure or a reticular structure.

2. The micro light emitting diode chip of claim 1, wherein, The first heat conduction structure comprises a liquid metal structure or a graphene-based nanofluid structure.

3. The micro light emitting diode chip of claim 1, wherein, The first heat conduction structure comprises a gallium-based alloy structure.

4. The micro light emitting diode chip of claim 1, wherein, The epitaxial layer comprises, in sequence, a buffer layer, a first semiconductor layer, a light emitting layer and a second semiconductor layer on the first surface.

5. The micro light emitting diode chip according to any one of claims 1 to 4, characterized in that, The micro light emitting diode chip further comprises: a second microfluidic network arranged on the buffer layer; and a second heat conduction structure arranged in the second microfluidic network. The micro light emitting diode chip further comprises:

6. The micro light emitting diode chip according to any one of claims 1 to 4, wherein, a self-repairing structure arranged on the substrate and adhered to the first surface. A projection of the self-repairing structure on the first surface covers the entire first surface; or, a projection of the self-repairing structure on the first surface covers part of the first surface.

7. The micro light emitting diode chip of claim 6, wherein, The first microfluidic network and the self-repairing structure are both arranged inside the substrate, the self-repairing structure is arranged between the first heat conduction structure and the first surface, and a projection of the self-repairing structure and the first heat conduction structure on the first surface coincides.

8. The micro light emitting diode chip of claim 6, wherein, The self-repairing structure comprises a furan / maleimide dynamic covalent polymer structure.

9. The micro light emitting diode chip of claim 6, wherein, The micro light emitting diode chip comprises:

10. A micro light emitting diode device, characterized by, a driving chip; and The micro light emitting diode chip according to any one of claims 1 to 9 is electrically connected to the driving chip. The micro light emitting diode device comprises the micro light emitting diode chip according to claim 10. ​ 11. A display device, characterized by comprising: ​

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