Display device using micro-LEDs and method of manufacturing the same

Abstract

A display device using a semiconductor light emitting element self-assembled in a fluid and a manufacturing method thereof are provided. Specifically, the semiconductor light emitting element is characterized by including a first conductive type electrode layer and a second conductive type electrode layer, a first conductive type semiconductor layer electrically connected to the first conductive type electrode layer, an active layer on the first conductive type semiconductor layer, and a second conductive type semiconductor layer on the active layer and electrically connected to the second conductive type electrode layer, one surface of the second conductive type semiconductor layer including a mesa structure formed by etching a part of the one surface, and the second conductive type electrode layer on the one surface of the second conductive type semiconductor layer including the mesa structure.

Description

Technical Field

[0001] This invention is applicable to the field of display devices, for example, it relates to a display device using micro LEDs (Light Emitting Diodes) and a method for manufacturing the same. Background Technology

[0002] In recent years, the field of display technology has seen continuous development of display devices with excellent characteristics such as thinness and flexibility. Conversely, the main commercially available displays are currently represented by LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Diodes).

[0003] However, LCDs suffer from slow response times and difficulty in achieving flexibility, while organic light-emitting diodes suffer from short lifespans and poor production yields.

[0004] On the other hand, light-emitting diodes (LEDs) are widely known as semiconductor light-emitting elements that convert electric current into light. Since the commercialization of red LEDs using GaAsP compound semiconductors in 1962, they have been used, along with green LEDs of the GaP:N series, as light sources for displaying images in electronic devices such as information and communication equipment. Therefore, a solution can be proposed to solve the aforementioned problems by utilizing the aforementioned semiconductor light-emitting element to achieve a display. The semiconductor light-emitting element has various advantages compared to filament-based light-emitting elements, such as longer lifespan, lower power consumption, excellent initial drive characteristics, and high vibration resistance.

[0005] To realize a display device utilizing such semiconductor light-emitting elements, a large number of semiconductor light-emitting elements need to be mounted on a substrate. In recent years, there has been continuous research and development on pick and place methods based on transfer substrates or methods for assembling semiconductor light-emitting elements onto a substrate in a fluid.

[0006] However, there are still many issues that need improvement in terms of manufacturing costs, assembly speed, and luminous efficiency.

[0007] In response, this invention proposes a novel form of semiconductor light-emitting element with high luminous efficiency that self-assembles in a fluid, and a method for manufacturing a display device using the semiconductor light-emitting element. Summary of the Invention

[0008] The problem the invention aims to solve

[0009] The objective of one embodiment of the present invention is to provide a display device and a manufacturing method utilizing a semiconductor light-emitting element.

[0010] Another objective of this invention is to provide a display device that can reduce manufacturing costs by using a vertical semiconductor light-emitting element.

[0011] Another objective of this invention is to provide a vertical semiconductor light-emitting element with improved luminous efficiency through self-assembly in a fluid, and a display device utilizing the vertical semiconductor light-emitting element.

[0012] Furthermore, another objective of this invention is to solve various problems not mentioned herein. Those skilled in the art will understand the full spirit of the invention through the specification and accompanying drawings.

[0013] means for solving problems

[0014] In a display device utilizing a semiconductor light-emitting element for achieving the above-mentioned objectives, the semiconductor light-emitting element is characterized by comprising: a first conductive electrode layer and a second conductive electrode layer, separately located at both ends of the semiconductor light-emitting element; a first conductive semiconductor layer electrically connected to the first conductive electrode layer; an active layer located on the first conductive semiconductor layer; and a second conductive semiconductor layer located on the active layer and electrically connected to the second conductive electrode layer; one side of the second conductive semiconductor layer includes a mesa structure formed by etching a portion of the side, and the second conductive electrode layer is located on the side of the second conductive semiconductor layer including the mesa structure.

[0015] As an example, the second conductive electrode layer is a transparent electrode layer.

[0016] As an example, the semiconductor light-emitting element further includes a conductive bonding layer, which is located on one side of the first conductive electrode layer and electrically connected to the first conductive electrode layer.

[0017] As an example, the first area of ​​the first conductive electrode layer is smaller than the second area of ​​the conductive bonding layer, and larger than the third area of ​​the top surface of the mesa structure.

[0018] As an embodiment, the semiconductor light-emitting element is characterized by comprising: a first passivation layer surrounding the top surface and side surface of the semiconductor light-emitting element; and a second passivation layer surrounding a portion of the bottom surface of the semiconductor light-emitting element; the second passivation layer being located in the region between the first conductive semiconductor layer and the conductive bonding layer.

[0019] As an example, the assembly substrate is characterized by having an assembly electrode, which generates a dielectric force in relation to the semiconductor light-emitting element through an electric field.

[0020] As an example, the platform structure is characterized in that its height is above the effective distance of the dielectric force exerted by the assembly substrate on the semiconductor light-emitting element.

[0021] As an example, the conductive bonding layer is a low-melting-point metal layer having a melting point of 100 to 250 degrees Celsius.

[0022] As an example, the semiconductor light-emitting element is an LED (Micro-LED) with a size in micrometers.

[0023] Another embodiment of the present invention provides a method for manufacturing a display device using a semiconductor light-emitting element, comprising: a step of forming a semiconductor light-emitting structure, wherein a semiconductor light-emitting structure having a mesa shape on one side is formed on a growth substrate; a step of transferring the semiconductor light-emitting structure to a temporary substrate; a step of manufacturing a vertical semiconductor light-emitting element, wherein a vertical semiconductor light-emitting element is manufactured by forming a conductive electrode layer and a conductive bonding layer on the semiconductor light-emitting structure; and an assembly step of assembling the vertical semiconductor light-emitting element onto an assembly substrate in a fluid by means of an electric field and a magnetic field.

[0024] As an example, the steps of forming the semiconductor light-emitting structure include: stacking a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer; forming a mesa shape by etching a portion of the top surface of the second conductive semiconductor layer; forming a second conductive electrode layer on the top surface of the second conductive semiconductor layer including the mesa shape; isolating individual semiconductor light-emitting structures by etching; and forming a first passivation layer on the top and side surfaces of the semiconductor light-emitting structure.

[0025] As an example, the steps of manufacturing a vertical semiconductor light-emitting element include: forming a first conductive electrode layer in a first region of the first conductive semiconductor layer exposed by the transfer step; and forming a second passivation layer in a second region of the first conductive semiconductor layer exposed by the transfer step.

[0026] As an example, the step of manufacturing a vertical semiconductor light-emitting element further includes the step of forming a conductive bonding layer that overlaps with the first conductive electrode layer and the second passivation layer.

[0027] As an example, the assembly substrate includes an assembly groove for assembling semiconductor light-emitting elements, and the conductive bonding layer of the semiconductor light-emitting elements is in contact with the bottom surface of the assembly groove.

[0028] The effects of the invention

[0029] According to one embodiment of the present invention, a display device utilizing a semiconductor light-emitting element and a method for manufacturing it can be provided.

[0030] Specifically, by fabricating a vertical semiconductor light-emitting element that includes a mesa structure on one side, it is possible to assemble it in a fluid along one direction. The mesa structure is formed by etching a portion of a conductive semiconductor layer, and a transparent electrode layer is formed on the side including the mesa structure, thereby improving the semiconductor light-emitting efficiency.

[0031] Furthermore, since vertical semiconductor light-emitting elements can produce more units on the same growth substrate area compared to horizontal semiconductor light-emitting elements, the manufacturing cost of display devices can be reduced.

[0032] Furthermore, according to another embodiment of the invention, other inventive effects not mentioned herein are also present. Those skilled in the art can understand these effects through the overall concept of the specification and drawings. Attached Figure Description

[0033] Figure 1 This is a conceptual diagram illustrating an embodiment of a display device utilizing the semiconductor light-emitting element of the present invention.

[0034] Figure 2 yes Figure 1 A magnified view of part A.

[0035] Figure 3a and Figure 3b yes Figure 2 BB line section view and CC line section view.

[0036] Figure 4 This is a conceptual diagram representing the flip-chip type semiconductor light-emitting element shown in Figure 3.

[0037] Figures 5a to 5c This is a conceptual diagram illustrating various ways to achieve color using flip-chip type semiconductor light-emitting elements.

[0038] Figure 6 This is a cross-sectional view illustrating a method for manufacturing a display device utilizing a semiconductor light-emitting element according to the present invention.

[0039] Figure 7 This is a perspective view illustrating another embodiment of the display device utilizing a semiconductor light-emitting element according to the present invention.

[0040] Figure 8 yes Figure 7 DD-line sectional view.

[0041] Figure 9 It means Figure 8 A conceptual diagram of a vertical semiconductor light-emitting element.

[0042] Figure 10 This is a flowchart that roughly illustrates a method for manufacturing a display device using semiconductor light-emitting elements.

[0043] Figure 11 This diagram illustrates an embodiment of a method for assembling a semiconductor light-emitting element onto a substrate using a self-assembly process.

[0044] Figure 12 yes Figure 11 An enlarged view of part E.

[0045] Figure 13 This is an embodiment of a vertical semiconductor light-emitting element that can self-assemble within a fluid.

[0046] Figure 14 This is a flowchart illustrating a method for manufacturing the semiconductor light-emitting element of the present invention.

[0047] Figures 15 to 16 This is a diagram specifically illustrating the structure of the semiconductor light-emitting element of the present invention.

[0048] Figure 17 This is another embodiment of the semiconductor light-emitting element of the present invention.

[0049] Figure 18 This is a flowchart illustrating the process of forming a semiconductor light-emitting structure with a mesa shape on one side.

[0050] Figure 19 Represented by sectional view Figure 18 A diagram illustrating the formation process of [something].

[0051] Figure 20 It means to Figure 19 A cross-sectional view of the process of transferring a semiconductor light-emitting structure onto a temporary substrate.

[0052] Figure 21 It means through the Figure 20 The flowchart illustrates the process of fabricating a vertical semiconductor light-emitting element by forming an electrode layer and a bonding layer on a semiconductor light-emitting structure.

[0053] Figure 22 Represented by sectional view Figure 21 A diagram of the manufacturing process.

[0054] Figure 23This is a cross-sectional view showing a semiconductor light-emitting element assembled on an assembly substrate. Detailed Implementation

[0055] The embodiments disclosed in this specification will now be described in detail with reference to the accompanying drawings. Identical or similar structural elements are given the same reference numerals regardless of the drawing numbers, and repeated descriptions will be omitted. The suffixes "module" and "part" used for structural elements in the following description are merely for ease of writing and do not inherently distinguish one another. Furthermore, in describing the technology disclosed in this specification, detailed descriptions of related well-known technologies are omitted when it is determined that a specific description of such technologies would obscure the essence of the technology disclosed in this specification. It should also be noted that the drawings are merely for ease of understanding of the technical concepts disclosed in this specification, and the technical concepts of the present invention should not be limited by the drawings.

[0056] The accompanying drawings are described below for ease of explanation, but other embodiments implemented by those skilled in the art in conjunction with at least two of the drawings are also within the scope of protection of this invention.

[0057] Additionally, it can be understood that when it is mentioned that a composition such as a layer, region, or substrate exists "on" other constituent elements, it means that it exists directly on top of other constituent elements or that there may be intermediate constituent elements between them.

[0058] The concept of display device described in this specification encompasses all display devices that display information using individual pixels or sets of individual pixels. Therefore, its use is not limited to finished products; it can also be applied to components. For example, a panel that is a component of a digital TV is also independently considered a display device under this specification. Finished products may include mobile phones, smartphones, laptop computers, digital broadcasting terminals, personal digital assistants (PDAs), portable multimedia players (PMPs), navigation devices, Slate PCs, Tablet PCs, UltraBooks, digital TVs, desktop computers, etc.

[0059] However, it will be readily understood by those skilled in the art that even new forms of products developed later can utilize the configuration of the embodiments described in this specification, as long as they are displayable devices.

[0060] In addition, the concept of semiconductor light-emitting elements mentioned in this specification covers LEDs, micro LEDs, etc., and they can be used interchangeably.

[0061] Figure 1 This is a conceptual diagram illustrating an embodiment of a display device utilizing a semiconductor light-emitting element according to the present invention.

[0062] like Figure 1 As shown, information processed in the control unit (not shown) of the display device 100 can be displayed on a flexible display.

[0063] In the case of flexible displays, for example, displays that can be bent, twisted, folded or rolled up by external forces can be included.

[0064] Furthermore, for example, a flexible display can be a display manufactured on a thin and flexible substrate that can be bent, folded, rolled up like paper while retaining the display characteristics of an existing flat panel display.

[0065] In the unbent state of the flexible display (e.g., a state with an infinite radius of curvature, hereinafter referred to as the first state), the display area of ​​the flexible display is planar. In the bent state caused by an external force (e.g., a state with a finite radius of curvature, hereinafter referred to as the second state), the display area can be curved. Figure 1 As shown, the information displayed in the second state can be visual information output to the curved surface. This visual information is achieved by independently controlling the emission of sub-pixels arranged in a matrix. A sub-pixel refers to, for example, the smallest unit used to implement a color.

[0066] The unit pixel of the flexible display can be implemented by a semiconductor light-emitting element. In this invention, a light-emitting diode (LED) is exemplified as a semiconductor light-emitting element that converts current into light. The LED is small in size, thus enabling it to function as a unit pixel even in the second state.

[0067] The flexible display realized using the light-emitting diode will now be described in detail with reference to the accompanying drawings.

[0068] Figure 2 yes Figure 1 A magnified view of part A.

[0069] Figure 3a and Figure 3b yes Figure 2 BB line section view and CC line section view.

[0070] Figure 4 This is a conceptual diagram representing the flip-chip type semiconductor light-emitting element shown in Figure 3.

[0071] Figures 5a to 5c This is a conceptual diagram showing various forms of color achieved by flip-chip type semiconductor light-emitting elements.

[0072] like Figure 2 , Figure 3a as well as Figure 3b As shown, an example of a display device 100 utilizing semiconductor light-emitting elements is a display device 100 using a passive matrix (PM) semiconductor light-emitting element. However, the examples described below can also be applied to semiconductor light-emitting elements using an active matrix (AM) semiconductor light-emitting element.

[0073] like Figure 2 As shown, Figure 1 The display device 100 shown includes a substrate 110, a first electrode 120, a conductive adhesive layer 130, a second electrode 140, and at least one semiconductor light-emitting element 150.

[0074] The substrate 110 can be a flexible substrate. For example, the substrate 110 may include glass or polyimide (PI) to realize a flexible display device. Alternatively, any material that is both insulating and flexible can be used, such as polyethylene naphthalate (PEN), polyethylene terephthalate (PET), etc. Furthermore, the substrate 110 can be any material that is transparent or opaque.

[0075] The substrate 110 may be a wiring substrate on which the first electrode 120 is disposed, and therefore the first electrode 120 may be located on the substrate 110.

[0076] like Figure 3a As shown, the insulating layer 160 can be disposed on the substrate 110 where the first electrode 120 is located, and the auxiliary electrode 170 can be located on the insulating layer 160. In this case, the state in which the insulating layer 160 is stacked on the substrate 110 can become a wiring substrate. More specifically, the insulating layer 160 is a material with insulating properties and flexibility, such as polyimide (PI), PET, or PEN, and can be integrally formed with the substrate 110 to form a substrate.

[0077] The auxiliary electrode 170 is an electrode that electrically connects the first electrode 120 and the semiconductor light-emitting element 150. It is located on the insulating layer 160 and is configured correspondingly to the position of the first electrode 120. For example, the auxiliary electrode 170 may be dot-shaped and can be electrically connected to the first electrode 120 through an electrode hole 171 penetrating the insulating layer 160. The electrode hole 171 can be formed by filling the through-hole with a conductive material.

[0078] like Figure 2 or Figure 3a As shown, a conductive adhesive layer 130 is formed on one side of the insulating layer 160, but the present invention is not necessarily limited to this. For example, a layer performing a specific function may be formed between the insulating layer 160 and the conductive adhesive layer 130, or a structure may be used where the conductive adhesive layer 130 is disposed on the substrate 110 without an insulating layer 160. In the structure where the conductive adhesive layer 130 is disposed on the substrate 110, the conductive adhesive layer 130 can function as an insulating layer.

[0079] The conductive adhesive layer 130 can be a layer that is both adhesive and conductive. Therefore, a conductive material and an adhesive material can be mixed together in the conductive adhesive layer 130. Furthermore, the conductive adhesive layer 130 is flexible, thereby enabling the display device to function flexibly.

[0080] As an example, the conductive adhesive layer 130 may be an anisotropic conductive film (ACF), an anisotropic conductive paste, a solution containing conductive particles, etc. The conductive adhesive layer 130 may be configured to allow electrical connections between itself in the Z direction throughout its thickness, while being electrically insulating in the horizontal XY direction. Therefore, the conductive adhesive layer 130 may be named a Z-axis conductive layer (however, hereinafter referred to as "conductive adhesive layer").

[0081] The anisotropic conductive film is a thin film in which an anisotropic conductive medium is mixed into an insulating substrate component, and only specific portions of it become conductive due to the anisotropic conductive medium when heat and pressure are applied. The following description describes the application of heat and pressure to the anisotropic conductive film; however, other methods can be used to make the anisotropic conductive film locally conductive. For example, the above methods can include applying either heat or pressure, or UV curing, etc.

[0082] Additionally, for example, the anisotropic conductive medium can be conductive spheres or conductive particles. For instance, the anisotropic conductive film is a thin film in the form of conductive spheres mixed into an insulating substrate component, where only specific portions become conductive due to the conductive spheres when heat and pressure are applied. The anisotropic conductive film can also be in the form of particles comprising a core of conductive material coated with an insulating film of a plurality of polymer materials. In this case, the insulating film in the portion subjected to heat and pressure is broken, thereby becoming conductive through the core. In this case, the core can be deformed to form layers that contact each other along the thickness direction of the film. As a more specific example, heat and pressure are applied to the entire anisotropic conductive film, thereby locally forming an electrical connection in the Z-axis direction due to the height difference of the objects bonded by the anisotropic conductive film.

[0083] As another example, anisotropic conductive films can be in the form of particles containing a plurality of conductive materials coated on an insulating core. In this case, the portion subjected to heat and pressure becomes conductive along the thickness direction of the film due to the deformation (pressing) of the conductive material. Alternatively, as another example, the conductive material can penetrate the insulating substrate member along the Z-axis and become conductive in the thickness direction of the film. In this case, the conductive material can have a pointed end.

[0084] The anisotropic conductive film can be a fixed array anisotropic conductive film (ACF) in which conductive spheres are inserted into one side of an insulating substrate member. More specifically, the insulating substrate member is formed of an adhesive material, and the conductive spheres are concentrated at the bottom of the insulating substrate member. If heat and pressure are applied to the substrate member, the conductive spheres deform together with the substrate member and become conductive in the vertical direction.

[0085] However, the present invention is not necessarily limited to this. The anisotropic conductive film may be in the form of conductive spheres randomly mixed into the insulating substrate component, or in the form of multiple layers with conductive spheres arranged in any one layer (double-ACF), etc.

[0086] Anisotropic conductive paste is a combination of paste and conductive spheres, which can be a paste in which conductive spheres are mixed with an insulating and adhesive substrate. Additionally, solutions containing conductive particles can be solutions containing conductive particles or nanoparticles.

[0087] Re-reference Figure 3a The second electrode 140 is separated from the auxiliary electrode 170 and located on the insulating layer 160. That is, the conductive adhesive layer 130 is disposed on the insulating layer 160 where the auxiliary electrode 170 and the second electrode 140 are located.

[0088] If a conductive adhesive layer 130 is formed with the auxiliary electrode 170 and the second electrode 140 in the state of the insulating layer 160, and the semiconductor light-emitting element 150 is connected in a flip-chip configuration by applying heat and pressure, then the semiconductor light-emitting element 150 is electrically connected to the first electrode 120 and the second electrode 140.

[0089] Reference Figure 4 The semiconductor light-emitting element can be a flip-chip type light-emitting element.

[0090] For example, the semiconductor light-emitting element includes a p-type electrode 156, a p-type semiconductor layer 155 formed on the p-type electrode 156, an active layer 154 formed on the p-type semiconductor layer 155, an n-type semiconductor layer 153 formed on the active layer 154, and an n-type electrode 152 disposed on the n-type semiconductor layer 153 and horizontally spaced from the p-type electrode 156. In this case, the p-type electrode 156 can be electrically connected to the auxiliary electrode 170 shown in FIG3 through a conductive adhesive layer 130, and the n-type electrode 152 can be electrically connected to the second electrode 140.

[0091] Re-reference Figure 2 , Figure 3a as well as Figure 3b An auxiliary electrode 170 is formed elongated in one direction, and one auxiliary electrode can be electrically connected to a plurality of semiconductor light-emitting elements 150. For example, with the auxiliary electrode as the center, the p-type electrodes of the semiconductor light-emitting elements on the left and right can be electrically connected to one auxiliary electrode.

[0092] More specifically, the semiconductor light-emitting element 150 is pressed into the conductive adhesive layer 130 by heat and pressure, thereby making only the portion between the p-type electrode 156 and the auxiliary electrode 170 of the semiconductor light-emitting element 150, and the portion between the n-type electrode 152 and the second electrode 140 of the semiconductor light-emitting element 150 conductive, while the remaining portion is not pressed into the semiconductor light-emitting element and is therefore non-conductive. As described above, the conductive adhesive layer 130 not only bonds the semiconductor light-emitting element 150 and the auxiliary electrode 170, and the semiconductor light-emitting element 150 and the second electrode 140 to each other, but also electrically connects them.

[0093] In addition, a plurality of semiconductor light-emitting elements 150 constitute a light-emitting element array, and a phosphor layer 180 is formed in the light-emitting element array.

[0094] The light-emitting element array may include a plurality of semiconductor light-emitting elements, each with a different brightness value. Each semiconductor light-emitting element 150 constitutes a unit pixel and is electrically connected to a first electrode 120. For example, there may be a plurality of first electrodes 120, and the semiconductor light-emitting elements may be arranged in a row, with each row of semiconductor light-emitting elements electrically connected to any one of the plurality of first electrodes.

[0095] Furthermore, since the semiconductor light-emitting elements are connected in a flip-chip configuration, semiconductor light-emitting elements grown on a transparent dielectric substrate can be used. Additionally, the semiconductor light-emitting element can be, for example, a nitride semiconductor light-emitting element. Because the semiconductor light-emitting element 150 has excellent brightness, it can form a single unit pixel even with a small size.

[0096] As shown in Figure 3, partition walls 190 can be formed between the semiconductor light-emitting elements 150. In this case, the partition walls 190 serve to separate individual unit pixels from each other and can be integrally formed with the conductive adhesive layer 130. For example, the partition walls can be formed by the substrate component of the anisotropic conductive film through the insertion of the semiconductor light-emitting elements 150 into the anisotropic conductive film.

[0097] In addition, if the substrate component of the anisotropic conductive film is black, no additional black insulator is required, and the partition wall 190 can also have reflective properties while increasing contrast.

[0098] As another example, the partition 190 may be additionally provided with a reflective partition. In this case, the partition 190 may include a black or white insulator, depending on the purpose of the display device. Using a partition with a white insulator can improve reflectivity, while using a partition with a black insulator can increase contrast while maintaining reflective properties.

[0099] The phosphor layer 180 may be located on the outer surface of the semiconductor light-emitting element 150. For example, the semiconductor light-emitting element 150 is a blue semiconductor light-emitting element that emits blue B light, and the phosphor layer 180 performs the function of converting the blue B light into the color of a unit pixel. The phosphor layer 180 may be a red phosphor layer 181 or a green phosphor layer 182 constituting an individual pixel.

[0100] That is, at the location where a red unit pixel is formed, a red phosphor layer 181 that converts blue light into red (R) light can be stacked on the blue semiconductor light-emitting element; at the location where a green unit pixel is formed, a green phosphor layer 182 that converts blue light into green (G) light can be stacked on the blue semiconductor light-emitting element. Alternatively, the portion forming the blue unit pixel can use only a blue semiconductor light-emitting element. In this case, red (R), green (G), and blue (B) unit pixels can form a single pixel. More specifically, phosphors of one color can be stacked along each line of the first electrode 120. Therefore, in the first electrode 120, a line can be an electrode controlling one color. That is, along the second electrode 140, red (R), green (G), and blue (B) can be sequentially arranged, thereby realizing a unit pixel.

[0101] However, the present invention is not necessarily limited to this. As an alternative phosphor, a combination of semiconductor light-emitting element 150 and quantum dot (QD) can also be used to realize unit pixels of red (R), green (G), and blue (B).

[0102] In addition, to improve contrast, a black matrix 191 can be arranged between the various phosphor layers. That is, this black matrix 191 can improve the contrast between light and dark areas.

[0103] However, the invention is not necessarily limited to this, and other structures for achieving blue, red, and green can be used.

[0104] Reference Figure 5a Each semiconductor light-emitting element 150 can be realized by a high-output light-emitting element that emits various types of light, such as blue light, by using gallium nitride (GaN) as the main material and adding indium (In) and / or aluminum (Al).

[0105] In this case, the semiconductor light-emitting element 150 can be a red, green, and blue semiconductor light-emitting element to realize a sub-pixel. For example, red, green, and blue semiconductor light-emitting elements R, G, and B can be alternately arranged, and red, green, and blue sub-pixels are formed into a pixel by the red, green, and blue semiconductor light-emitting elements, thereby enabling full-color display.

[0106] Reference Figure 5bThe semiconductor light-emitting element 150a may include a white light-emitting element W, each having a yellow phosphor layer disposed thereon. In this case, to achieve a unit pixel, a red phosphor layer 181, a green phosphor layer 182, and a blue phosphor layer 183 may be disposed on the white light-emitting element W. Alternatively, a unit pixel may be achieved by repeatedly applying red, green, and blue color filters to the white light-emitting element W.

[0107] Reference Figure 5c Alternatively, a structure can be adopted in which a red phosphor layer 184, a green phosphor layer 185, and a blue phosphor layer 186 are disposed on the ultraviolet light-emitting element 150b. As described above, the semiconductor light-emitting element can not only use visible light, but also can be used in the entire region including ultraviolet (UV) light. The semiconductor light-emitting element can be extended to use ultraviolet (UV) light as an excitation source for the upper phosphor.

[0108] Referring again to this example, the semiconductor light-emitting element is located on the conductive adhesive layer, thus forming a unit pixel in the display device. Because of the excellent brightness of the semiconductor light-emitting element, individual unit pixels can be formed even when the size is small.

[0109] The size of the single semiconductor light-emitting element 150 as described above can be, for example, a rectangular or square element with a side length of 80 μm or less. In the case of a rectangle, it can have a size of 20 x 80 μm or less.

[0110] Furthermore, even if a square semiconductor light-emitting element 150 with a side length of 10 μm is used as a unit pixel, sufficient brightness can be displayed to achieve the display device.

[0111] Therefore, as an example, if the size of a unit pixel is a rectangular pixel with one side length of 600μm and the other side length of 300μm, then the distance between semiconductor light-emitting elements is relatively large.

[0112] Therefore, in this case, it is possible to realize a flexible display device with high image quality of HD or higher.

[0113] Display devices using the aforementioned semiconductor light-emitting elements can be manufactured using a novel manufacturing method. The following refers to... Figure 6 The manufacturing method will be described.

[0114] Figure 6 This is a cross-sectional view illustrating a method for manufacturing a display device utilizing a semiconductor light-emitting element according to the present invention.

[0115] like Figure 6As shown, firstly, a conductive adhesive layer 130 is formed on the insulating layer 160 where the auxiliary electrode 170 and the second electrode 140 are located. The insulating layer 160 is stacked on a wiring substrate 110, on which the first electrode 120, the auxiliary electrode 170, and the second electrode 140 are disposed. In this case, the first electrode 120 and the second electrode 140 can be arranged in directions orthogonal to each other. Furthermore, to realize a flexible display device, the wiring substrate 110 and the insulating layer 160 can each comprise glass or polyimide (PI).

[0116] For example, the conductive adhesive layer 130 can be implemented by an anisotropic conductive film, for which an anisotropic conductive film can be coated on the substrate where the insulating layer 160 is located.

[0117] Next, a temporary substrate 112, which is provided with a plurality of semiconductor light-emitting elements 150 that correspond to the positions of the auxiliary electrode 170 and the second electrode 140 and constitute individual pixels, is configured such that the semiconductor light-emitting elements 150 face the auxiliary electrode 170 and the second electrode 140.

[0118] In this case, the temporary substrate 112 is the growth substrate for growing the semiconductor light-emitting element 150, which can be a sapphire substrate or a silicon substrate.

[0119] When the semiconductor light-emitting element is formed on a wafer basis, it can be effectively used for a display device by having spacing and size that enable the display device.

[0120] Next, the wiring substrate and the temporary substrate 112 are thermally bonded. For example, the wiring substrate and the temporary substrate 112 can be thermally bonded using an ACF press head. The wiring substrate and the temporary substrate 112 are bonded together by the thermal bonding. Through thermal bonding, due to the characteristics of the anisotropic conductive film, conductivity is achieved only in the portion between the semiconductor light-emitting element 150 and the auxiliary electrode 170 and the second electrode 140, thereby allowing the electrodes and the semiconductor light-emitting element 150 to be electrically connected. At this time, the semiconductor light-emitting element 150 is inserted into the interior of the anisotropic conductive film, thereby forming a partition wall between the semiconductor light-emitting elements 150.

[0121] Next, the temporary substrate 112 is removed. For example, the temporary substrate 112 can be removed using laser lift-off (LLO) or chemical lift-off (CLO).

[0122] Finally, the temporary substrate 112 is removed, exposing the semiconductor light-emitting element 150 to the outside. If necessary, a transparent insulating layer (not shown) can be formed by coating a wiring substrate on which the semiconductor light-emitting element 150 is bonded, such as silicon oxide (SiOx).

[0123] Additionally, the process may include a step of forming a phosphor layer on one side of the semiconductor light-emitting element 150. For example, the semiconductor light-emitting element 150 may be a blue semiconductor light-emitting element that emits blue B light, and a red or green phosphor for converting this blue B light into the color of a unit pixel may be formed in the form of a layer on one side of the blue semiconductor light-emitting element.

[0124] The manufacturing method or structure of the display device utilizing semiconductor light-emitting elements described above can be modified into various forms. As an example, a vertical semiconductor light-emitting element can also be used in the aforementioned display device.

[0125] Furthermore, in the variations or embodiments described below, the same or similar reference numerals are given to the same or similar configurations as those in the foregoing examples, and the initial description replaces the description therewith.

[0126] Figure 7 This is a perspective view illustrating another embodiment of the display device utilizing a semiconductor light-emitting element according to the present invention. Figure 8 yes Figure 7 DD-line sectional view, Figure 9 It means Figure 8 A conceptual diagram of a vertical semiconductor light-emitting element.

[0127] Referring to the accompanying drawings, the display device may be a display device using vertical semiconductor light-emitting elements in a passive matrix (PM) configuration.

[0128] The display device includes a substrate 210, a first electrode 220, a conductive adhesive layer 230, a second electrode 240, and at least one semiconductor light-emitting element 250.

[0129] The substrate 210 is a wiring substrate on which the first electrode 220 is disposed, and it may include polyimide (PI) to realize a flexible display device. Alternatively, any material with insulating and flexible properties can be used.

[0130] The first electrode 220 is located on the substrate 210 and can be formed as an electrode in the shape of a bar along one direction. The first electrode 220 can function as a data electrode.

[0131] A conductive adhesive layer 230 is formed on the substrate 210 where the first electrode 220 is located. In display devices using flip-chip type light-emitting elements, the conductive adhesive layer 230 can be anisotropic conductive film (ACF), anisotropic conductive paste, a solution containing conductive particles, etc. However, in this embodiment, a case where the conductive adhesive layer 230 is implemented using an anisotropic conductive film is also exemplified.

[0132] If, after placing the anisotropic conductive film with the first electrode 220 on the substrate 210, heat and pressure are applied to connect the semiconductor light-emitting element 250, then the semiconductor light-emitting element 250 is electrically connected to the first electrode 220. Preferably, the semiconductor light-emitting element 250 is positioned on the first electrode 220.

[0133] As mentioned earlier, electrical connections are formed because localized areas of the anisotropic conductive film become conductive in the thickness direction when heat and pressure are applied. Therefore, the anisotropic conductive film is divided into portions that are conductive in the thickness direction and portions that are not conductive.

[0134] In addition, since the anisotropic conductive film contains adhesive components, the conductive adhesive layer 230 not only electrically connects the semiconductor light-emitting element 250 and the first electrode 220, but also achieves mechanical bonding.

[0135] As described above, the semiconductor light-emitting element 250 is located on the conductive adhesive layer 230, thereby forming a single pixel in the display device. Because the semiconductor light-emitting element 250 has excellent brightness, a small size is also possible to form a single unit pixel. The size of the single semiconductor light-emitting element 250 as described above can be, for example, a rectangle or square with a side length of 80 μm or less. In the case of a rectangle, for example, it can be a size of 20 x 80 μm or less.

[0136] The semiconductor light-emitting element 250 can be a vertical structure.

[0137] A plurality of second electrodes 240 are located between vertical semiconductor light-emitting elements, the plurality of second electrodes 240 being arranged in a direction intersecting the length direction of the first electrode 220 and electrically connected to the semiconductor light-emitting element 250.

[0138] Reference Figure 9This semiconductor light-emitting element 250 includes a p-type electrode 256, a p-type semiconductor layer 255 formed on the p-type electrode 256, an active layer 254 formed on the p-type semiconductor layer 255, an n-type semiconductor layer 253 formed on the active layer 254, and an n-type electrode 252 formed on the n-type semiconductor layer 253. In this case, the lower p-type electrode 256 can be electrically connected to the first electrode 220 through a conductive adhesive layer 230, and the upper n-type electrode 252 can be electrically connected to the second electrode 240 (described later). Since this semiconductor light-emitting element 250 can have electrodes arranged vertically, it has the significant advantage of being able to reduce chip size.

[0139] Re-reference Figure 8 A phosphor layer 280 may be formed on one side of the semiconductor light-emitting element 250. For example, if the semiconductor light-emitting element 250 is a blue semiconductor light-emitting element 251 that emits blue B light, a phosphor layer 280 for converting this blue B light into the color of a unit pixel may be provided. In this case, the phosphor layer 280 may be a red phosphor 281 and a green phosphor 282 constituting an individual pixel.

[0140] That is, at the location where a red unit pixel is formed, a red phosphor 281 that can convert blue light into red (R) light can be stacked on top of the blue semiconductor light-emitting element; at the location where a green unit pixel is formed, a green phosphor 282 that can convert blue light into green (G) light can be stacked on top of the blue semiconductor light-emitting element. Alternatively, in the portion where a blue unit pixel is formed, only a single blue semiconductor light-emitting element can be used. In this case, the red (R), green (G), and blue (B) unit pixels can form a single pixel.

[0141] However, the present invention is not necessarily limited to this. As mentioned above, in display devices using flip chip type light-emitting elements, other structures for realizing blue, red, and green can be used.

[0142] Referring again to this embodiment, the second electrode 240 is located between the semiconductor light-emitting elements 250 and is electrically connected to the semiconductor light-emitting elements 250. For example, the semiconductor light-emitting elements 250 are arranged in a plurality of columns, and the second electrode 240 may be located between the columns of the semiconductor light-emitting elements 250.

[0143] Since the distance between the semiconductor light-emitting elements 250 that form individual pixels is sufficiently large, the second electrode 240 can be located between the semiconductor light-emitting elements 250.

[0144] The second electrode 240 can be formed as an electrode in the shape of a bar along one direction, and can be arranged in a direction perpendicular to the first electrode.

[0145] Furthermore, the second electrode 240 and the semiconductor light-emitting element 250 can be electrically connected via a connecting electrode protruding from the second electrode 240. More specifically, the connecting electrode can be an n-type electrode of the semiconductor light-emitting element 250. For example, the n-type electrode is formed as an ohmic electrode for ohmic contact, and the second electrode covers at least a portion of the ohmic electrode by printing or deposition. Thus, the second electrode 240 and the n-type electrode of the semiconductor light-emitting element 250 can be electrically connected.

[0146] Re-reference Figure 8 The second electrode 240 may be located on the conductive adhesive layer 230. Depending on the situation, a transparent insulating layer (not shown) including silicon oxide (SiOx) may be formed on the substrate 210 on which the semiconductor light-emitting element 250 is formed. When the second electrode 240 is placed after the transparent insulating layer is formed, the second electrode 240 is located on the transparent insulating layer. Alternatively, the second electrode 240 may be formed to be spaced apart from the conductive adhesive layer 230 or the transparent insulating layer.

[0147] If a transparent electrode such as ITO (Indium Tin Oxide) is used to position the second electrode 240 on the semiconductor light-emitting element 250, there is a problem with the poor adhesion between the ITO material and the n-type semiconductor layer. Therefore, the present invention positions the second electrode 240 between the semiconductor light-emitting elements 250, thereby having the advantage of not using a transparent electrode such as ITO. Therefore, light extraction efficiency can be improved by using a conductive material with good adhesion to the n-type semiconductor layer as the horizontal electrode, without being limited by the choice of transparent material.

[0148] Re-reference Figure 8 The partition wall 290 can be located between the semiconductor light-emitting elements 250. That is, in order to separate the semiconductor light-emitting elements 250 that form individual pixels, a partition wall 290 can be disposed between the semiconductor light-emitting elements 250. In this case, the partition wall 290 can serve to separate the individual unit pixels from each other, and the partition wall 290 can be integrally formed with the conductive adhesive layer 230. For example, by inserting the semiconductor light-emitting elements 250 into the anisotropic conductive film, the partition wall can be formed from the substrate component of the anisotropic conductive film.

[0149] In addition, if the substrate component of the anisotropic conductive film is black, the partition wall 290 can have reflective properties while increasing contrast even without an additional black insulator.

[0150] As another example, the partition 290 may additionally include a reflective partition. The partition 290 may include a black or white insulator, depending on the purpose of the display device.

[0151] If the second electrode 240 is located directly above the conductive adhesive layer 230 between the semiconductor light-emitting elements 250, the partition wall 290 can be located between each semiconductor light-emitting element 250 and the second electrode 240. Therefore, by using the semiconductor light-emitting elements 250, individual unit pixels can be constructed with small sizes, and since the distance between the semiconductor light-emitting elements 250 becomes relatively large, the second electrode 240 can be located between the semiconductor light-emitting elements 250, thus achieving the effect of a flexible display device capable of realizing HD image quality.

[0152] In addition, such as Figure 8 As shown, in order to improve contrast, a black matrix 291 can be arranged between each phosphor. That is, this black matrix 291 can improve the contrast between light and dark areas.

[0153] Figure 10 This is a diagram that roughly illustrates the manufacturing method of a display device using semiconductor light-emitting elements.

[0154] First, a semiconductor light-emitting element is formed on a growth substrate (S1010). The semiconductor light-emitting element may include a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer. Additionally, it may include a first conductive electrode formed on the first conductive semiconductor layer and a second conductive electrode formed on the second conductive semiconductor layer.

[0155] The semiconductor light-emitting element can be a horizontal or vertical type. However, in the case of a vertical type semiconductor light-emitting element, since the first conductive electrode and the second conductive electrode are facing each other, after separating the semiconductor light-emitting element from the growth substrate, a process for forming conductive electrodes in either direction can be added in subsequent processes. Additionally, as will be explained later, for self-assembly processes, the semiconductor light-emitting element may include a magnetic layer.

[0156] Typically, for a semiconductor light-emitting element to be used in a display device, three types of semiconductor light-emitting elements are required, each emitting light in the colors Red (R), Green (G), and Blue (B). Since a single-color semiconductor light-emitting element is formed on a growth substrate, an additional substrate is needed to realize a display device using these three types of semiconductor light-emitting elements for a single pixel. Therefore, it is necessary to separate the individual semiconductor light-emitting elements from the growth substrate and assemble or transfer them to a final substrate. The final substrate is the substrate on which the process of forming wiring electrodes that apply voltage to the semiconductor light-emitting elements is performed, enabling the semiconductor light-emitting elements to emit light.

[0157] Therefore, semiconductor light-emitting elements emitting various colors can be first moved to a transfer substrate or assembly substrate (S1020) and then transferred again to the final substrate. Depending on the situation, if a wiring process is directly performed on the transfer substrate or assembly substrate, the transfer substrate or assembly substrate functions as the final substrate.

[0158] There are roughly three methods for placing semiconductor light-emitting elements on a transfer substrate or assembly substrate (S1020).

[0159] The first method involves moving a semiconductor light-emitting element from a growth substrate to a transfer substrate using a stamping process (S1021). The stamping process refers to a process in which a semiconductor light-emitting element is separated from the growth substrate using a substrate made of a flexible material with adhesive protrusions. The semiconductor light-emitting element on the growth substrate can be selectively separated by adjusting the spacing and arrangement of the protrusions.

[0160] The second method involves assembling semiconductor light-emitting elements onto an assembly substrate using a self-assembly process (S1022). Since the self-assembly process requires separating the semiconductor light-emitting elements from the growth substrate and having them exist as individual semiconductor light-emitting elements, a required number of semiconductor light-emitting elements are separated from the growth substrate using a laser lift-off (LLO) process or similar method. Subsequently, the semiconductor light-emitting elements are dispersed in a fluid and assembled onto the assembly substrate using an electromagnetic field.

[0161] In the self-assembly process, individual semiconductor light-emitting elements that realize R, G, and B colors can be assembled simultaneously on an assembly substrate, or individual semiconductor light-emitting elements of a single color can be assembled using a single assembly substrate.

[0162] The third method is a combination of the stamping process and the self-assembly process (S1023). First, the semiconductor light-emitting element is placed on the assembly substrate using the self-assembly process, and then the semiconductor light-emitting element is moved to the final substrate using the stamping process. Regarding the assembly substrate, since it cannot be formed on a large area due to factors such as the position of the assembly substrate during the self-assembly process, contact with fluids, and the influence of electromagnetic fields, it is possible to assemble the semiconductor light-emitting element using an assembly substrate of appropriate area, and then perform a process of multiple transfers to a large-area final substrate using the stamping process.

[0163] If a plurality of semiconductor light-emitting elements constituting a single unit pixel are disposed on a final substrate, a wiring process for electrically connecting the semiconductor light-emitting elements is performed (S1030).

[0164] The wiring electrodes formed by the wiring process electrically connect the semiconductor light-emitting elements assembled or transferred onto the substrate to the substrate. Additionally, transistors for active matrix driving can be pre-formed on the lower part of the substrate. Therefore, the wiring electrodes can be electrically connected to the transistors.

[0165] On the other hand, for large-area display devices, a large number of semiconductor light-emitting elements are required, therefore a self-assembly process is preferred. Furthermore, to improve assembly speed, it is preferable to simultaneously assemble semiconductor light-emitting elements of various colors onto a single assembly substrate during the self-assembly process. Additionally, to assemble the semiconductor light-emitting elements of each color into specific locations on the assembly substrate, a mutually exclusive structure may be necessary.

[0166] Figure 11 This diagram illustrates an embodiment of a method for assembling a semiconductor light-emitting element onto a substrate using a self-assembly process.

[0167] Figure 12 yes Figure 11 An enlarged view of part E.

[0168] Reference Figure 11 and Figure 12 The semiconductor light-emitting element 1150 can be inserted into the chamber 1130 filled with fluid 1120.

[0169] Subsequently, the assembly substrate 1110 can be disposed on the chamber 1130. According to an embodiment, the assembly substrate 1110 can also be inserted into the chamber 1130. In this case, the insertion direction of the assembly substrate 1110 is the direction in which the assembly groove 1111 of the assembly substrate 1110 faces the fluid 1120.

[0170] A pair of electrodes 1112 and 1113 corresponding to the individual semiconductor light-emitting elements 1150 to be assembled can be formed on the assembly substrate 1110. The electrodes 1112 and 1113 can be implemented using transparent electrodes (ITO) or other common materials. The electrodes 1112 and 1113 generate an electric field when a voltage is applied, thereby acting as assembly electrodes to stably fix the semiconductor light-emitting elements 1150 in contact with the assembly groove.

[0171] Specifically, an alternating voltage can be applied to the electrodes 1112 and 1113, and the semiconductor light-emitting element 1150 floating around the electrodes 1112 and 1113 can become polarized due to dielectric polarization. Furthermore, the dielectric-polarized semiconductor light-emitting element can move or be fixed in a specific direction due to the non-uniform electric field formed around the electrodes 1112 and 1113. This is called dielectricophoresis (DEP), which can be used to stably fix the semiconductor light-emitting element 1150 in the assembly tank 1111 in the self-assembly process of the present invention. The intensity of the dielectricophoresis (DEP force) is directly proportional to the intensity of the electric field; therefore, the intensity of the dielectricophoresis varies depending on the degree of dielectric polarization within the semiconductor light-emitting element.

[0172] In addition, the spacing between the electrodes 1112 and 1113 can be formed, for example, smaller than the width of the semiconductor light-emitting element 1150 and the diameter of the assembly groove 1111, thereby enabling more precise fixation of the assembly position of the electric field-based semiconductor light-emitting element 1150.

[0173] Furthermore, an insulating layer 1114 is formed on the electrodes 1112 and 1113, thereby preventing the electrodes 1112 and 1113 from being affected by the fluid 1120 and preventing leakage of current flowing on the electrodes 1112 and 1113. For example, the insulating layer 1114 can be formed as a single layer or multiple layers of inorganic insulators such as silicone or alumina, or organic insulators. In addition, the insulating layer 1114 can have a minimum thickness for preventing damage to the electrodes 1112 and 1113 during the assembly of the semiconductor light-emitting element 1150, and can have a maximum thickness for stable assembly of the semiconductor light-emitting element 1150.

[0174] A partition wall 1115 may be formed on the upper part of the insulating layer 1114. A portion of the partition wall 1115 may be located on the upper part of the electrodes 1112 and 1113, while the remaining portion may be located on the upper part of the assembly substrate 1110.

[0175] For example, when manufacturing the assembly substrate 1110, an assembly groove 1111 can be formed by removing a portion of the partition wall formed on the entire upper part of the insulating layer 1114, and each semiconductor light-emitting element 1150 is attached to the assembly groove 1111 of the assembly substrate 1110.

[0176] like Figure 12 As shown, an assembly groove 1111 for attaching a semiconductor light-emitting element 1150 is formed on the assembly substrate 1110, and the surface of the assembly groove 1111 can contact the fluid 1120. The assembly groove 1111 can guide the semiconductor light-emitting element 1150 to the accurate assembly position.

[0177] Furthermore, the partition wall 1115 can be formed with a predetermined inclination from the opening of the assembly groove 1111 toward the bottom surface. For example, by adjusting the inclination of the partition wall 1115, the assembly groove 1111 can have an opening and a bottom surface, and the area of ​​the opening can be larger than the area of ​​the bottom surface. Thus, the semiconductor light-emitting element 1150 can be assembled into a precise position on the bottom surface of the assembly groove 1111.

[0178] On the other hand, the assembly slot 1111 may have a shape and size corresponding to the shape of the assembled semiconductor light-emitting element 1150. This prevents other semiconductor light-emitting elements from being assembled into the assembly slot 1111, or prevents multiple semiconductor light-emitting elements from being assembled into the assembly slot 1111.

[0179] Furthermore, the depth of the assembly groove 1111 can be less than the vertical height of the semiconductor light-emitting element 1150. Thus, the semiconductor light-emitting element 1150 can have a structure protruding from between the partition walls 1115, and can easily contact the protrusions of the transfer substrate during a possible transfer process after assembly.

[0180] In addition, such as Figure 12 As shown, after the assembly substrate 1110 is configured, the assembly device 1140, including the magnet, can move along with the assembly substrate 1110. To maximize the influence area of ​​the magnetic field within the fluid 1120, the assembly device 1140 can move in contact with the assembly substrate 1110. For example, the assembly device 1140 may include a plurality of magnets, or it may include magnets having dimensions corresponding to those of the assembly substrate 1110. In this case, the movement distance of the assembly device 1140 can also be limited to a specified range.

[0181] The semiconductor light-emitting element 1150 in the chamber 1130 can move toward the assembly device 1140 via the magnetic field generated by the assembly device 1140.

[0182] like Figure 12As shown, the semiconductor light-emitting element 1150 can move toward the assembly device 1140 and enter the assembly tank 1111 to contact the assembly substrate 1110.

[0183] Additionally, a magnetic layer may be included inside the semiconductor light-emitting element to enable the semiconductor light-emitting element 1150 to perform a self-assembly process.

[0184] On the other hand, the electric field generated by the electrodes 1112 and 1113 of the assembly substrate 1110 can prevent the semiconductor light-emitting element 1150 in contact with the assembly substrate 1110 from detaching due to the movement of the assembly device 1140.

[0185] Therefore, through Figure 11 and Figure 12 The self-assembly method based on electromagnetic fields shown allows a plurality of semiconductor light-emitting elements 1150 to be assembled simultaneously on the assembly substrate 1110.

[0186] Figure 13 This is an embodiment of a vertical semiconductor light-emitting element that can self-assemble within a fluid.

[0187] Because horizontal semiconductor light-emitting elements have conductive electrodes formed on one side of the element that connect all the conductive semiconductor layers, the manufacturing process is easier. However, fewer elements can be manufactured on the same growth substrate area compared to vertical semiconductor light-emitting elements. Therefore, in display devices using millions or more semiconductor light-emitting elements, using vertical semiconductor light-emitting elements helps reduce manufacturing costs.

[0188] On the other hand, additional wiring electrodes are required at the lower part of the assembly groove of the assembly substrate to assemble the vertical semiconductor light-emitting element onto the assembly substrate. The wiring electrodes can be electrically connected to a conductive electrode layer located at one end of the vertical semiconductor light-emitting element.

[0189] first, Figure 13(a) is a diagram showing the shape of a typical vertical semiconductor light-emitting element. A first conductive semiconductor layer 1353, an active layer 1354, and a second conductive semiconductor layer 1355 are stacked. A first conductive electrode layer 1352 is formed below the first conductive semiconductor layer 1353, and a second conductive electrode layer 1356 is formed above the second conductive semiconductor layer 1355. Furthermore, a passivation layer 1357, used to protect the semiconductor light-emitting element from external environmental influences, surrounds the outer portion of the element. In a portion of the area where the passivation layer is not formed, a conductive bonding layer 1359 is electrically connected to the first conductive electrode layer 1352. The conductive bonding layer 1359 is used to obtain electrical connection with wiring electrodes pre-formed on the assembly substrate, and can primarily use a low-melting-point metal layer with a melting point below 250 degrees Celsius. By using this low-melting-point metal layer, a reliable electrical connection between the element and the substrate can be achieved by heating the substrate after assembling the semiconductor light-emitting element. Additionally, the second conductive electrode layer 1356 can be a transparent electrode layer such as ITO.

[0190] on the other hand, Figure 13 (a) The structure of the vertical semiconductor light-emitting element is difficult to apply. Figures 11 to 12 The self-assembly process involves, as mentioned earlier, a semiconductor light-emitting element within a fluid that can contact an assembly tank on an assembly substrate via a magnetic field and be assembled into the tank based on the dielectric force of the assembly electrodes. This dielectric force is proportional to the distance between the assembly electrodes and the semiconductor light-emitting element, and, at the same distance, proportional to the area. That is, when assembling a semiconductor light-emitting element within a fluid, it is advantageous for one side of the semiconductor light-emitting element to be larger than the other if a specific orientation is desired.

[0191] therefore, Figure 13 (a) The semiconductor light-emitting element is likely to be randomly assembled on the assembly substrate without orientation. Typically, in the formation of a semiconductor light-emitting element, the thickness of the conductive electrode layer and the passivation layer is very thin compared to the thickness of the conductive semiconductor layer. Therefore, the area of ​​the top or bottom surface of the semiconductor light-emitting element does not change significantly due to the formation of the conductive electrode layer and the passivation layer. Therefore, when assuming that the dielectric force based on the electric field acts on... Figure 13 (a) When constructing a semiconductor light-emitting element, the top and bottom surfaces of the semiconductor light-emitting element have similar areas, making it difficult to directionally assemble them onto the assembly substrate. Although a thicker conductive bonding layer 1359 can be formed to cause a difference in area, the semiconductor light-emitting element is then assembled with the side opposite to the side where the conductive bonding layer 1359 is formed, making it difficult to achieve electrical connection with wiring electrodes pre-formed on the assembly substrate.

[0192] Therefore, in the case of vertical semiconductor light-emitting elements, the area of ​​the assembly surface needs to be larger than the area of ​​the other surface, and it is preferable to form a low-melting-point bonding layer on the assembly surface.

[0193] Figure 13 (b) is taken into consideration Figure 13 (a) A cross-sectional view of a semiconductor light-emitting element that can be assembled in one direction within a fluid, based on the problem points.

[0194] A first conductive semiconductor layer 1453, an active layer 1454, and a second conductive semiconductor layer 1455 are stacked. A first conductive electrode layer 1452 is formed below the first conductive semiconductor layer 1453, and a second conductive electrode layer 1456 is formed above the second conductive semiconductor layer 1455. A passivation layer 1457, used to protect the semiconductor light-emitting element from external environmental influences, surrounds the outer portion of the element. In a portion where the passivation layer is not formed, a conductive bonding layer 1459 is electrically connected to the first conductive electrode layer 1452. The conductive bonding layer 1459 is used to obtain electrical connection with wiring electrodes pre-formed on the assembly substrate and can primarily use a low-melting-point metal layer with a melting point below 250 degrees Celsius. By using this low-melting-point metal layer, a reliable electrical connection between the element and the substrate can be achieved by heating the substrate after assembling the semiconductor light-emitting element. Furthermore, the second conductive electrode layer 1456 can be a transparent electrode layer such as ITO.

[0195] exist Figure 13 In case (b), in order to define the assembly surface of the semiconductor light-emitting element assembled on the substrate in the fluid, a mesa structure is formed by etching a portion of the second conductive semiconductor layer 1455, thereby creating a difference in the area at both ends of the semiconductor light-emitting element.

[0196] like Figure 13 As shown in (b), due to the mesa structure of the second conductive semiconductor layer 1455, the area of ​​the side where the second conductive electrode layer 1456 is located is smaller than the area of ​​the side where the conductive bonding layer 1459 is formed. Therefore, the semiconductor light-emitting element is assembled on the substrate with the side where the conductive bonding layer 1459 is formed.

[0197] However, in Figure 13 In the case of the semiconductor light-emitting element (b), since most of the light is emitted from the region where the second conductive electrode layer 1456 is formed on the top surface of the mesa structure, the luminous efficiency may be detrimental. Furthermore, since the area of ​​the conductive bonding layer 1459 is smaller than the area of ​​the conductive electrode layer 1452, the luminous efficiency may decrease in subsequent processes for bonding the element and the substrate after assembly due to poor open circuitry or high contact resistance.

[0198] Below, refer to Figures 14 to 23 The present invention will describe a vertical semiconductor light-emitting element with a novel structure that can solve the above-mentioned problems, can be assembled in a fluid along one direction, and can improve luminous efficiency.

[0199] Figure 14 This is a flowchart illustrating a method for manufacturing the semiconductor light-emitting element of the present invention.

[0200] First, a semiconductor light-emitting structure with one side shaped like a mesa is formed on the growth substrate (S1410). At this point, compared to the final semiconductor light-emitting element, the semiconductor light-emitting structure is in a state without the first conductive electrode layer, the conductive bonding layer, and the second passivation layer, which will be explained later.

[0201] Next, a transfer step (S1420) is performed to transfer the semiconductor light-emitting structure to a temporary substrate. Through the transfer step (S1420), the boundary surface of the semiconductor light-emitting structure that abuts the growth substrate can be exposed.

[0202] Next, the fabrication of the vertical semiconductor light-emitting element is completed by forming an electrode layer and a conductive bonding layer on the semiconductor light-emitting structure (S1430). The electrode layer is formed on the boundary surface of the semiconductor light-emitting structure exposed by the transfer step (S1420). Furthermore, a second passivation layer may be formed between the electrode layer and the conductive bonding layer.

[0203] Finally, the manufactured vertical semiconductor light-emitting element is assembled onto the assembly substrate within the fluid using electric and magnetic fields (S1440).

[0204] On the other hand, given the overall concept of this specification, deletions and modifications are permitted to a level that can be understood by those skilled in the art. Figure 14 Some of the steps in the flowchart shown are also within the scope of protection of this invention.

[0205] Figures 15 to 16 This is a diagram specifically illustrating the structure of the semiconductor light-emitting element of the present invention.

[0206] like Figure 15As shown, a first conductive semiconductor layer 1553, an active layer 1554, and a second conductive semiconductor layer 1555 form a stacked structure. A first conductive electrode layer 1552 is formed below the first conductive semiconductor layer 1553, and a second conductive electrode layer 1556 is formed above the second conductive semiconductor layer 1555. Furthermore, a first passivation layer 1557 surrounds the top and side surfaces of the element, while a second passivation layer 1558 surrounds a portion of the bottom surface of the element to protect the semiconductor light-emitting element from external environmental influences. Additionally, a conductive bonding layer 1559, overlapping a portion of the second passivation layer 1558, is electrically connected to the first conductive electrode layer 1552. On the other hand, the first passivation layer 1557 and the second passivation layer 1558 may be made of the same material.

[0207] Below, on Figure 13 (b) Vertical semiconductor light-emitting element and Figure 15 To explain the structural differences of semiconductor light-emitting elements, firstly, Figure 15 The second conductive electrode layer 1556 is located on the entire top surface of the second conductive semiconductor layer 1555, which has a mesa structure. Therefore, the luminous efficiency can be improved by increasing the semiconductor light-emitting area.

[0208] In addition, by forming a second passivation layer 1558 on the temporary substrate after transfer and before forming a conductive bonding layer 1559, the conductive bonding layer 1559 can fully surround the first conductive electrode layer 1552, thereby reducing the contact resistance.

[0209] If structural differences are confirmed numerically, then as follows: Figure 16 As shown, the width X1 of the first conductive electrode layer 1552 can be less than or equal to the width X2 of the conductive bonding layer 1559. Furthermore, the width X1 of the first conductive electrode layer 1552 needs to be greater than the width X3 of the top surface of the mesa structure 1555a formed on the second conductive semiconductor layer 1555. Since the difference in width can be considered proportional to the difference in area, it can be assumed that the area of ​​the conductive bonding layer 1559 of the semiconductor light-emitting element is greater than the area of ​​the mesa structure. Therefore, when the semiconductor light-emitting element is assembled on an assembly substrate, the side of the semiconductor light-emitting element with the conductive bonding layer 1559 formed can be mounted into the assembly slot of the assembly substrate.

[0210] Furthermore, preferably, the height Y of the mesa structure 1555a is above the effective distance of the dielectric force exerted by the assembly substrate on the semiconductor light-emitting element. For example, experiments have confirmed that in a circular semiconductor light-emitting element with a width of 50 μm and a height of 10 μm, the range of the dielectric force is approximately 200 nm. Therefore, if the height Y of the mesa structure 1555a is greater than 200 nm, the dielectric force only acts on the top surface of the mesa structure 1555a; however, if it is within 100 nm, the dielectric force can act on the entire surface of the second conductive semiconductor layer 1555, including the mesa structure 1555a. That is, the difference is unlikely to be large compared to the area of ​​the conductive bonding layer 1559, which corresponds to the opposite surface of the second conductive semiconductor layer 1555. Therefore, if the height Y of the mesa structure 1555a is greater than 200 nm, the semiconductor light-emitting element can be assembled along the direction of the conductive bonding layer 1559. However, if it is within 200 nm (e.g., 100 nm), it is difficult to determine which direction it is assembled in.

[0211] Figure 17 This is another embodiment of the semiconductor light-emitting element of the present invention.

[0212] As described above, the semiconductor light-emitting element of the present invention is characterized in that a second conductive electrode layer is formed on the top surface of a second conductive semiconductor layer including a mesa structure, and a conductive adhesive layer that is wider than the first conductive electrode layer is formed. Therefore, various embodiments of the semiconductor light-emitting element exist within the scope of satisfying the above features.

[0213] For example, such as Figure 17 As shown in (a), a semiconductor light-emitting element with a two-mesa structure can be manufactured. In this semiconductor light-emitting element, a first conductive semiconductor layer 1753, an active layer 1754, and a second conductive semiconductor layer 1755 form a stacked structure. A first conductive electrode layer 1752 is formed at the bottom of the first conductive semiconductor layer 1753, and a second conductive electrode layer 1756 is formed over the entire upper region of the second conductive semiconductor layer 1755. Furthermore, a first passivation layer 1757 surrounds the top and side surfaces of the element, and a second passivation layer 1758 surrounds a portion of the bottom surface of the element to protect the semiconductor light-emitting element from external environmental influences. Additionally, a conductive bonding layer 1759, overlapping the second passivation layer 1758, is electrically connected to the first conductive electrode layer 1752.

[0214] When forming a semiconductor light-emitting structure on a growth substrate, a plurality of mesa structures can be formed on one side of the semiconductor light-emitting structure using a relatively simple process (photolithography and etching). However, the total area of ​​the top surfaces of the plurality of mesa structures needs to be smaller than the area of ​​the conductive bonding layer 1759 on the opposite side for assembly in one direction on the assembly substrate.

[0215] In addition, such as Figure 17 As shown in (b), in other embodiments of the semiconductor light-emitting element, although the shapes of the first conductive semiconductor layer 1853, the active layer 1854, the second conductive semiconductor layer 1855, and the second conductive electrode layer 1856 are similar to those shown in (b), the semiconductor light-emitting element in other embodiments is similar to that shown in (b). Figure 15 Similar to semiconductor light-emitting elements, but the shape of the second passivation layer 1858 overlapping the conductive bonding layer 1859 can be different. For example, in Figure 17 In (a), a second passivation layer 1758 is formed only between the conductive bonding layer 1759 and the first conductive semiconductor layer 1753, while Figure 17 In (b), a portion of the second passivation layer 1758 may be formed between the first conductive electrode layer 1852 and the conductive bonding layer 1859. Additionally, the width of the conductive bonding layer 1859 may be the same as the side width of the element including the first passivation layer 1857.

[0216] The reason for this shape is that the first conductive electrode layer 1852, the second passivation layer 1858, and the conductive bonding layer 1859 are formed on a temporary substrate by an additional process, and therefore can vary depending on the detailed sequence and conditions of the process.

[0217] Therefore, the structure of the semiconductor light-emitting element of the present invention is not limited to Figure 17 The examples provided are as follows.

[0218] Figure 18 This is a flowchart illustrating the process of forming a semiconductor light-emitting structure with a mesa shape on one side.

[0219] First, a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer are stacked (S1411). Next, a mesa shape is formed by etching a portion of the top surface of the second conductive semiconductor layer (S1412). Then, a second conductive electrode layer is formed on the top surface of the second conductive semiconductor layer including the mesa shape (S1413), and isolation is performed by etching to define a single semiconductor light-emitting structure (S1414). Finally, a first passivation layer is formed on the top and side surfaces of the semiconductor light-emitting structure (S1415).

[0220] On the other hand, given the overall concept of this specification, deletions and modifications are permitted to a level that can be understood by those skilled in the art. Figure 18 Some of the steps in the flowchart shown are also within the scope of protection of this invention.

[0221] Figure 19 Represented by sectional view Figure 18 A diagram illustrating the formation process of a semiconductor light-emitting structure.

[0222] like Figure 19 As shown in (a), firstly, a first conductive semiconductor layer 1953, an active layer 1954, and a second conductive semiconductor layer 1955 are stacked on a growth substrate 1910.

[0223] After that, as Figure 19 As shown in (b), a mesa shape 1955a is formed by etching a portion of the top surface of the second conductive semiconductor layer 1955. At this time, the etching can be performed such that the height of the mesa shape 1955a reaches a distance above the effective distance where electrophoretic forces do not exert their effect in subsequent assembly processes.

[0224] After that, as Figure 19 As shown in (c), a second conductive electrode layer 1956 is formed over the entire area of ​​the top surface of the second conductive semiconductor layer, which includes the mesa shape. In this case, the second conductive electrode layer 1956 can be a transparent electrode layer like ITO, and is formed with a very thin thickness so that it can be removed by an etching process.

[0225] Then, an etching process is used to isolate the individual semiconductor light-emitting structure.

[0226] Finally, as Figure 19 As shown in (e), a first passivation layer 1957 is formed on the top and side surfaces of the isolated semiconductor light-emitting structure. Therefore, as... Figure 19 As shown in (e), the final semiconductor light-emitting structure 1960 is formed by stacking a first conductive semiconductor layer 1953, an active layer 1954, a second conductive semiconductor layer 1955 having a mesa shape, and a second conductive electrode layer 1956, and is surrounded by a first passivation layer 1957.

[0227] Figure 20 It means to Figure 19 A cross-sectional view of the process of transferring a semiconductor light-emitting structure onto a temporary substrate.

[0228] like Figure 20 As shown in (a), the semiconductor light-emitting structure 1960 formed on the growth substrate 1910 can be transferred to the temporary substrate 2010 provided with the adhesive layer 2020 for subsequent processes.

[0229] The adhesive layer 2020 may be an organic stamping layer and may have protrusions corresponding to the semiconductor light-emitting structure 1960.

[0230] like Figure 20 As shown in (b), if the semiconductor light-emitting structure 1960 comes into contact with the adhesive layer 2020 of the temporary substrate 2010, and then a laser or the like is irradiated onto the back side of the growth substrate 1910, the semiconductor light-emitting structure 1960 can be transferred from the growth substrate 1910 to the temporary substrate 2010.

[0231] The reason for transferring the semiconductor light-emitting structure to the temporary substrate 2010 is to expose the side of the semiconductor light-emitting structure 1960 that is not exposed from the growth substrate 1910. A first conductive electrode layer, a second passivation layer, and a conductive bonding layer can be formed on the exposed surface.

[0232] Figure 21 It means through the Figure 20 The flowchart illustrates the process of fabricating a vertical semiconductor light-emitting element by forming an electrode layer and a bonding layer on a semiconductor light-emitting structure.

[0233] First, through Figure 20 The first region of the first conductive semiconductor layer exposed by the transfer process forms the first conductive electrode layer (S1431).

[0234] Subsequently, a second passivation layer is formed in the second region of the first conductive semiconductor layer (S1432). The first region and the second region can be distinguished on the same surface of the first conductive semiconductor layer.

[0235] Finally, the conductive bonding layer is formed to overlap with the first conductive electrode layer and the second passivation layer (S1433).

[0236] On the other hand, given the overall concept of this specification, deletions and modifications are permitted to a level that can be understood by those skilled in the art. Figure 21 Some of the steps in the flowchart shown are also within the scope of protection of this invention.

[0237] Figure 22 Represented by sectional view Figure 21 A diagram illustrating the manufacturing process of semiconductor light-emitting elements.

[0238] like Figure 22 As shown in (a), a first conductive electrode layer 1952, electrically connected to the first conductive semiconductor layer, is formed on the exposed surface of the semiconductor light-emitting structure 1960 transferred to the adhesive layer 2020 on the temporary substrate 2010. At this time, as... Figure 22As shown in (a), the first conductive electrode layer 1952 is formed in the first region of the exposed semiconductor light-emitting structure 1960. Specifically, referring to... Figure 19 A first conductive electrode layer 1952 is formed on the exposed surface of the first conductive semiconductor layer.

[0239] After that, as Figure 22 As shown in (b), a second passivation layer 1958 is formed in the second region of the remaining exposed surface of the first conductive semiconductor layer where the first conductive electrode layer 1952 is not formed.

[0240] After that, as Figure 22 As shown in (c), the conductive bonding layer 1959 is formed to overlap with the first conductive electrode layer 1952 and the second passivation layer 1958 formed on one side of the semiconductor light-emitting structure 1960. The conductive bonding layer 1959 may be a low-melting-point metal layer with a melting point of less than 250 degrees Celsius, and can be electrically connected to the assembly substrate after the assembly process. Therefore, a semiconductor light-emitting element 1950 is manufactured in which the first conductive electrode layer 1952, the second passivation layer 1958, and the conductive bonding layer 1959 are provided in the semiconductor light-emitting structure 1960.

[0241] In addition, such as Figure 22 As shown in (d), the semiconductor light-emitting element 1950 can be individually separated from the temporary substrate in order to perform subsequent assembly processes.

[0242] Figure 23 This is a cross-sectional view showing the semiconductor light-emitting element of the present invention assembled on the assembly substrate.

[0243] Specifically, Figure 22 The individual semiconductor light-emitting elements can be mounted in the assembly tank of the assembly substrate within a fluid via electric and magnetic fields. Therefore, as... Figure 23 As shown, once the assembly process is complete, the semiconductor light-emitting element 2350 is located within the assembly groove of the assembly substrate. The assembly substrate may have wiring electrodes 2316 formed on the substrate 2310, which are electrically connected to the conductive bonding layer 2359 of the semiconductor light-emitting element 2350. Additionally, assembly electrodes 2312 and 2313 for generating an electric field, a dielectric film 2314 for protecting the assembly electrodes 2312 and 2313, and a partition wall 2315 for forming the assembly groove may be located on the substrate 2310.

[0244] like Figure 23As shown, the semiconductor light-emitting element 2350 has a vertical semiconductor light-emitting structure and conductive electrode layers are provided at both ends. In particular, the conductive bonding layer 2359 is located on the assembly surface of the semiconductor light-emitting element 2350 that contacts the bottom surface of the assembly groove of the assembly substrate. This is because the area of ​​the conductive bonding layer is relatively large compared to the opposite surface with a mesa shape, so during the assembly process, the semiconductor light-emitting element 2350 is assembled along the direction of the conductive bonding layer.

[0245] The above description is merely illustrative of the technical concept of the present invention. Those skilled in the art can make various modifications and variations without departing from the technical concept of the present invention.

[0246] Therefore, the embodiments disclosed in this invention are not intended to limit the technical concept of the invention, but are for illustration, and the technical concept of the invention is not limited to these embodiments.

[0247] The scope of protection of this invention should be interpreted by the claims, and should be interpreted as including all technical ideas within the same scope as those claims.

Claims

1. A display device comprising mounting a plurality of semiconductor light-emitting elements on an assembly substrate using an electric field, characterized in that, At least one of the plurality of said semiconductor light-emitting elements includes: The first conductive electrode layer and the second conductive electrode layer are located separately at both ends of the semiconductor light-emitting element; The first conductive semiconductor layer is electrically connected to the first conductive electrode layer; An active layer is located on the first conductivity semiconductor layer; and A second conductive semiconductor layer is located on the active layer and is electrically connected to the second conductive electrode layer; One side of the second conductive semiconductor layer includes a mesa structure formed by etching a portion of said side. The second conductive electrode layer is located over the entire area of ​​the side of the second conductive semiconductor layer that includes the mesa structure; The height of the mesa structure is set such that the dielectric force exerted by the assembly substrate on the semiconductor light-emitting element only acts on the top surface of the mesa structure.

2. The display device according to claim 1, characterized in that, The second conductive electrode layer is a transparent electrode layer.

3. The display device according to claim 1, characterized in that, The semiconductor light-emitting element further includes a conductive bonding layer, which is located on one side of the first conductive electrode layer and electrically connected to the first conductive electrode layer.

4. The display device according to claim 3, characterized in that, The first area of ​​the first conductive electrode layer is smaller than the second area of ​​the conductive bonding layer, and larger than the third area of ​​the top surface of the mesa structure.

5. The display device according to claim 4, characterized in that, The semiconductor light-emitting element includes: A first passivation layer surrounds the top and side surfaces of the semiconductor light-emitting element; and A second passivation layer surrounds a portion of the bottom surface of the semiconductor light-emitting element; The second passivation layer is located in the region between the first conductive semiconductor layer and the conductive bonding layer.

6. The display device according to claim 1, characterized in that, The assembly substrate is provided with at least one assembly electrode, and at least one of the assembly electrodes generates dielectric force through an electric field acting on the semiconductor light-emitting element.

7. The display device according to claim 3, characterized in that, The conductive bonding layer is a low-melting-point metal layer with a melting point of 100 to 250 degrees Celsius.

8. The display device according to claim 1, characterized in that, The semiconductor light-emitting element is an LED (Micro-LED) with a size in micrometers.

9. The display device according to claim 3, characterized in that, The semiconductor light-emitting element further includes a passivation layer that surrounds the top and side surfaces of the semiconductor light-emitting element. The side end of the passivation layer is aligned with the side end of the conductive bonding layer.

10. A method for manufacturing a display device, characterized in that, include: The step of forming a semiconductor light-emitting structure involves forming a semiconductor light-emitting structure with a mesa shape on one side of a growth substrate. The transfer step involves transferring the semiconductor light-emitting structure onto a temporary substrate. The step of manufacturing a vertical semiconductor light-emitting element involves forming a conductive electrode layer and a conductive bonding layer in the semiconductor light-emitting structure to manufacture the vertical semiconductor light-emitting element; as well as The assembly step involves assembling the vertical semiconductor light-emitting element onto an assembly substrate within a fluid using electric and magnetic fields. The step of forming the semiconductor light-emitting structure includes: The step of stacking a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer; The step of forming a mesa shape by etching a portion of the top surface of the second conductive semiconductor layer; The step of forming a second conductive electrode layer in the entire region of the top surface of the mesa-shaped semiconductor layer; The height of the platform shape is set such that the dielectric force exerted by the assembly substrate on the semiconductor light-emitting element only acts on the top surface of the platform shape.

11. The method for manufacturing a display device according to claim 10, characterized in that, The step of forming the semiconductor light-emitting structure includes: Isolation steps for individual semiconductor light-emitting structures are defined through etching processes; and The step of forming a first passivation layer on the top and side surfaces of the semiconductor light-emitting structure.

12. The method for manufacturing a display device according to claim 11, characterized in that, The steps for manufacturing the vertical semiconductor light-emitting element include: The step of forming a first conductive electrode layer in the first region of the first conductive semiconductor layer exposed by the transfer step; and The step of forming a second passivation layer in the second region of the first conductive semiconductor layer exposed by the transfer step.

13. The method for manufacturing a display device according to claim 12, characterized in that, The step of manufacturing a vertical semiconductor light-emitting element further includes: forming a conductive bonding layer to overlap with the first conductive electrode layer and the second passivation layer.

14. The method for manufacturing a display device according to claim 13, characterized in that, The assembly substrate includes assembly slots for assembling vertical semiconductor light-emitting elements. The conductive bonding layer of the vertical semiconductor light-emitting element is in contact with the bottom surface of the assembly trench.

15. The method for manufacturing a display device according to claim 10, characterized in that, The vertical semiconductor light-emitting element includes: A first conductive electrode layer and a second conductive electrode layer separated by an active layer; At least one passivation layer is disposed on the second conductive electrode layer; and A conductive bonding layer is disposed below the first conductive electrode layer. At least one side end of the passivation layer is aligned with the side end of the conductive bonding layer.

16. A semiconductor light-emitting element, characterized in that, include: First conductivity type semiconductor layer; Active layer; Second conductivity type semiconductor layer; The first conductive electrode layer is located below the first conductive semiconductor layer; The second conductive electrode layer is located on the second conductive semiconductor layer; as well as At least one passivation layer is located on the second conductive electrode layer. The first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer are stacked together. The second conductive semiconductor layer includes at least one mesa structure, and at least one mesa structure protrudes from an adjacent portion of the second conductive semiconductor layer. The second conductive semiconductor layer covers at least one of the mesa structures and adjacent portions of the second conductive semiconductor layer. The second conductive electrode layer is located over the entire area of ​​one side of the second conductive semiconductor layer that includes the mesa structure; The height of the mesa structure is set such that the dielectric force exerted by the assembly substrate on the semiconductor light-emitting element only acts on the top surface of the mesa structure.

17. The semiconductor light-emitting element according to claim 16, characterized in that, The semiconductor light-emitting element further includes a conductive bonding layer, which is located beneath the first conductive electrode layer and at least one of the passivation layers. One side of the conductive bonding layer is larger than one side of the first conductive electrode layer.

18. The semiconductor light-emitting element according to claim 16, characterized in that, The semiconductor light-emitting element further includes a conductive bonding layer, which is located beneath the first conductive electrode layer and at least one of the passivation layers. The side end of the conductive bonding layer is aligned with the side end of at least one of the passivation layers.

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