Display device using micro LEDs and manufacturing method thereof

Abstract

The present invention discloses a micro LED display device that minimizes short - circuit defects by using a semiconductor light - emitting element having a multi - layer passivation layer, and a manufacturing method thereof. Here, in a display device using a plurality of semiconductor light - emitting elements according to an embodiment of the present invention, it is characterized in that at least one of the semiconductor light - emitting elements includes a first - conductivity - type semiconductor layer, a second - conductivity - type semiconductor layer, an active layer, a first - conductivity - type electrode, a second - conductivity - type electrode, and a first passivation layer and a second passivation layer configured to sequentially surround the sides of the first - conductivity - type semiconductor layer and the second - conductivity - type semiconductor layer, and the second passivation layer is located in a region other than the portion in contact with the first electrode and the second electrode among the upper portions of the first - conductivity - type electrode and the second - conductivity - type electrode.

Description

Technical Field

[0001] The present invention relates to a display device, for example, a display device using micro LEDs (Light Emitting Diodes) and a manufacturing method thereof. Background Art

[0002] In recent years, in the field of display technology, display devices with excellent characteristics such as thinness and flexibility have been continuously developed. On the contrary, currently commercialized main displays are represented by LCD (Liquid Crystal Display) and organic light emitting diodes.

[0003] However, LCDs have problems of slow response time and difficulty in achieving flexibility, while organic light emitting diodes have problems of short service life and low production yield.

[0004] On the other hand, a light emitting diode (LED) is well known as a semiconductor light emitting element that converts current into light. Since the commercialization of a red LED using a GaAsP compound semiconductor in 1962, it has been used as a light source for displaying images of electronic devices such as information communication devices together with GaP:N series green LEDs. Therefore, a solution to the above-mentioned problems can be proposed by implementing a display using the semiconductor light emitting element. The semiconductor light emitting element has various advantages such as a long service life, low power consumption, excellent initial driving characteristics, and high vibration resistance compared to a light emitting element based on a filament.

[0005] In recent years, the size of such semiconductor light emitting elements has been reduced to several tens of micrometers. Therefore, when using the semiconductor light emitting element to implement a display device, a very large number of semiconductor light emitting elements need to be assembled on a wiring substrate of the display device.

[0006] However, in the above assembly process, it is very difficult to place a large number of semiconductor light emitting elements at specific positions on the wiring substrate. Therefore, there is a problem that various defects may occur in subsequent wiring processes if the semiconductor light emitting elements are not assembled at the specific positions. Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] An object of an embodiment of the present invention is to provide a display device and a manufacturing method using a semiconductor light emitting element.

[0009] An object of an embodiment of the present invention is also to provide a display device and a manufacturing method thereof that can perform a stable wiring process after assembling a semiconductor light-emitting element on a display substrate.

[0010] Furthermore, an object of an embodiment of the present invention is also to solve various problems not mentioned herein. Those skilled in the art can understand from the description of the entire specification or the drawings.

[0011] Means for Solving the Problems

[0012] A manufacturing method of a display device using a semiconductor light-emitting element for achieving the above object includes: a step of forming a semiconductor light-emitting element on a first substrate; a step of transferring the semiconductor light-emitting element to a second substrate; a step of coating an insulating layer on the semiconductor light-emitting element transferred to the second substrate; and a step of forming wiring electrodes electrically connected to the semiconductor light-emitting element; the step of forming the semiconductor light-emitting element includes: a step of forming a semiconductor light-emitting structure including a first conductivity type semiconductor layer, an active layer, a second conductivity type semiconductor layer, a first conductivity type electrode, and a second conductivity type electrode on the first substrate; a step of forming a first passivation layer on the semiconductor light-emitting structure; a step of selectively removing the first passivation layer formed on the upper portions of the first conductivity type electrode and the second conductivity type electrode of the semiconductor light-emitting structure; and a step of forming a second passivation layer on the semiconductor light-emitting structure.

[0013] As an embodiment, a step of removing the second passivation layer is further included between the step of transferring to the second substrate and the step of coating the insulating layer.

[0014] As an embodiment, it is characterized in that the step of removing the second passivation layer is performed by a wet etching process.

[0015] As an embodiment, the step of coating the insulating layer includes: a step of planarizing the upper portion of the insulating layer; and a step of exposing at least a part of the upper portion of the semiconductor light-emitting element.

[0016] As an embodiment, the step of forming the wiring electrodes includes a step of forming a first electrode electrically connected to the first conductivity type electrode of the semiconductor light-emitting element and a second electrode electrically connected to the second conductivity type electrode.

[0017] As an embodiment, the step of forming the first electrode and the second electrode includes a step of removing the second passivation layer formed on the upper portions of the first conductivity type electrode and the second conductivity type electrode.

[0018] As an example, the steps of forming the first electrode and the second electrode include the step of selectively removing the second passivation layer in the overlapping regions between the first electrode and the first conductive type electrode and between the second electrode and the second conductive type electrode.

[0019] The step of selectively removing the second passivation layer is characterized in that it is performed by a dry etching process.

[0020] A display device using a plurality of semiconductor light emitting elements according to another embodiment of the present invention, wherein at least one of the semiconductor light emitting elements includes: a first conductive type semiconductor layer; a second conductive type semiconductor layer located on the first conductive type semiconductor layer; an active layer disposed between the first conductive type semiconductor layer and the second conductive type semiconductor layer; a second conductive type electrode located on the second conductive type semiconductor layer; a first conductive type electrode located in a region of the first conductive type semiconductor layer exposed due to partial etching of the second conductive type semiconductor layer and the active layer; and a first passivation layer and a second passivation layer sequentially disposed to surround the sides of the first conductive type semiconductor layer and the second conductive type semiconductor layer; the second passivation layer is located in a region of the upper part of the first conductive type electrode except for the part in contact with the first electrode, and the second passivation layer is located in a region of the upper part of the second conductive type electrode except for the part in contact with the second electrode.

[0021] As an example, it is characterized in that in the upper part of the first conductive type semiconductor layer, the first passivation layer and the second passivation layer are sequentially disposed in a region except for the part in contact with the first conductive type electrode, and in the upper part of the second conductive type semiconductor layer, the first passivation layer and the second passivation layer are sequentially disposed in a region except for the part in contact with the first conductive type electrode.

[0022] As an example, it is characterized in that in the upper part of the first conductive type semiconductor layer, the second passivation layer is located in a region except for the part in contact with the first conductive type electrode, and in the upper part of the second conductive type semiconductor layer, the second passivation layer is located in a region except for the part in contact with the first conductive type electrode.

[0023] As an example, it is characterized in that the first etching ratio of the first passivation layer is less than the second etching ratio of the second passivation layer.

[0024] As an example, it is characterized in that the first passivation layer includes the same material as the second passivation layer.

[0025] As an example, it is characterized in that the thickness of the second passivation layer is 100 nm or more thinner than the thickness of the first passivation layer.

[0026] As an embodiment, it is characterized in that a magnetic layer is included under the first conductivity type electrode or the second conductivity type electrode.

[0027] As an embodiment, it is characterized in that the semiconductor light emitting element is an LED (Micro-LED) having a size in the micron unit.

[0028] Effects of the Invention

[0029] According to an embodiment of the present invention, a display device and a manufacturing method using a semiconductor light emitting element can be provided.

[0030] Specifically, in the case where a wiring process is performed after assembling the semiconductor light emitting element on a substrate, by forming a multiple passivation layer on the semiconductor light emitting element, the passivation layer of only the portion connected to the wiring electrode can be selectively removed, thereby enabling a stable wiring process that minimizes the risk of short circuit defects.

[0031] Therefore, it has the technical effect of reducing short (Short) or open (Open) defects of the semiconductor light emitting element that may occur in the wiring process.

[0032] Furthermore, according to another embodiment of the present invention, there are also additional technical effects not mentioned herein. Those skilled in the art can understand through the technical concept of the entire specification and drawings. Brief Description of the Drawings

[0033] Figure 1 It is a conceptual diagram showing an embodiment of a display device using a semiconductor light emitting element of the present invention.

[0034] Figure 2 Is Figure 1 A partial enlarged view of part A of

[0035] Figure 3a And Figure 3b Is Figure 2 A cross-sectional view taken along line B-B and a cross-sectional view taken along line C-C of

[0036] Figure 4 It is a conceptual diagram showing a flip chip type semiconductor light emitting element of FIG. 3.

[0037] Figures 5a to 5c It is a conceptual diagram showing various ways of realizing colors for a flip chip type semiconductor light emitting element.

[0038] Figure 6 It is a cross-sectional view showing a manufacturing method of a display device using a semiconductor light emitting element of the present invention.

[0039] Figure 7It is a perspective view showing another embodiment of the display device using a semiconductor light-emitting element of the present invention.

[0040] Figure 8 It is Figure 7 a cross-sectional view taken along the D-D line of

[0041] Figure 9 It is a conceptual diagram showing Figure 8 a vertical semiconductor light-emitting element of

[0042] Figure 10 It is a flowchart showing a manufacturing method of a display device using a semiconductor light-emitting element according to another embodiment of the present invention.

[0043] Figure 11 It specifically shows the process of forming Figure 10 a multi-passivation layer of

[0044] Figure 12 It specifically shows the process of performing Figure 10 a wiring process of

[0045] Figure 13 It is a cross-sectional view of a semiconductor light-emitting structure formed on Figure 10 a first substrate of

[0046] Figure 14 It is after Figure 13 a first passivation layer is formed on the semiconductor light-emitting structure of

[0047] Figure 15 It shows a cross-sectional view after selectively removing only Figure 14 the first passivation layer formed on the upper part of the conductive-type electrode of the semiconductor light-emitting structure of

[0048] Figure 16 It is after Figure 15 a second passivation layer is formed on the semiconductor light-emitting structure of

[0049] Figure 17 It is a cross-sectional view after Figure 16 a wiring process is performed on the semiconductor light-emitting element of

[0050] Figure 18 It is after Figure 16 a wiring process is performed on the semiconductor light-emitting element of

[0051] Figure 19 It specifically shows another wiring process method performed on Figure 16 the semiconductor light-emitting element of

[0052] Figure 20 It is inFigure 19 Cross-sectional view of a semiconductor light-emitting device in which a wiring process is performed.

[0053] Figure 21 It is a diagram showing various electrode shapes that can be formed by a wiring process.

[0054] Figure 22 It represents the case where wiring electrodes are formed at various positions for a semiconductor light-emitting device that performs Figure 17 the wiring process. Detailed Description of the Invention

[0055] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the accompanying drawings. The same or similar structural elements are given the same reference numerals regardless of the figure numbers, and redundant descriptions thereof will be omitted. In the following description, the suffixes “module” and “section” for structural elements are given or used interchangeably only for the convenience of writing the specification, and they do not have meanings or functions for mutual distinction by themselves. In addition, in the process of describing the technology disclosed in this specification, when it is judged that a detailed description of related known technologies will make the gist of the technology disclosed in this specification unclear, the detailed description thereof will be omitted. In addition, it should be noted that the drawings are only for easily understanding the technical idea disclosed in this specification, and the technical idea of the present invention should not be limited by the drawings.

[0056] Hereinafter, although each drawing will be described for convenience, other embodiments implemented by those skilled in the art in combination with at least two drawings also fall within the scope of protection of the present invention.

[0057] In addition, it can be understood that when it is mentioned that a component such as a layer, a region, or a substrate exists “on” another component, it means that it directly exists on another component or an intermediate component may also exist between them.

[0058] The concept of the display device described in this specification encompasses all display devices that display information using unit pixels or a set of unit pixels. Therefore, its use is not limited to finished products and can also be applied to components. For example, a panel as a component of a digital TV also independently belongs to the display device of this specification. Finished products may include mobile phones, smart phones, laptop computers, digital broadcast terminals, personal digital assistants (PDAs), portable multimedia players (PMPs), navigation devices, slate PCs, tablet PCs, ultra books, digital TVs, desktop computers, etc.

[0059] However, it is easily understandable to those skilled in the art that even for newly developed products in the future, as long as they are displayable devices, the configurations of the embodiments described in this specification can be applied.

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

[0061] Figure 1 It is a conceptual diagram showing an embodiment of a display device using a semiconductor light-emitting element of the present invention.

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

[0063] Regarding the flexible display, for example, it may include a display that can be bent, folded, twisted, folded, or curled by an external force.

[0064] Furthermore, for example, the flexible display can be a display that is fabricated on a thin and flexible substrate that can be bent, folded, folded, or curled like paper while maintaining the display characteristics of an existing flat panel display.

[0065] In a state where the flexible display cannot be bent (for example, a state with an infinite radius of curvature, hereinafter referred to as the first state), the display area of the flexible display becomes flat. In a state where it becomes bent from the first state due to an external force (for example, a state with a finite radius of curvature, hereinafter referred to as the second state), the display area can be a curved surface. As Figure 1 shown, the information displayed in the second state can be visual information output to the curved surface. Such visual information is achieved by independently controlling the light emission of unit pixels (sub-pixels) arranged in a matrix form. The unit pixel refers to, for example, the minimum unit for realizing one color.

[0066] The unit pixels of the flexible display can be realized by semiconductor light-emitting elements. In the present invention, as a kind of semiconductor light-emitting element that converts current into light, a light-emitting diode (LED) is exemplified. The light-emitting diode has a small size, and thus can play the role of a unit pixel even in the second state.

[0067] Next, with reference to the accompanying drawings, a detailed description of the flexible display realized by the light-emitting diode will be given.

[0068] Figure 2 is Figure 1 a partial enlarged view of part A of

[0069] Figure 3a and Figure 3b is Figure 2 The cross-sectional views taken along line B-B and line C-C of

[0070] Figure 4 is a conceptual diagram showing a flip-chip type semiconductor light-emitting device of FIG. 3.

[0071] Figures 5a to 5c is a conceptual diagram showing various forms of colors achieved with a flip-chip type semiconductor light-emitting device.

[0072] As Figure 2 , Figure 3a and Figure 3b shown, as the display device 100 using a semiconductor light-emitting device, a display device 100 using a semiconductor light-emitting device of the passive matrix (PM) method is exemplified. However, the examples described below can also be applied to semiconductor light-emitting devices of the active matrix (AM) method.

[0073] As Figure 2 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 device 150.

[0074] The substrate 110 may be a flexible substrate. For example, the substrate 110 may include glass or polyimide (PI) to realize a flexible display device. In addition, any material having insulation and flexibility can be used, such as PEN (Polyethylene Naphthalate), PET (Polyethylene Terephthalate), etc. Further, the substrate 110 may be made of any material, either transparent or opaque.

[0075] Since the substrate 110 may be a wiring substrate for disposing the first electrode 120, the first electrode 120 may be located on the substrate 110.

[0076] As Figure 3aAs shown, the insulating layer 160 may be disposed on the substrate 110 where the first electrode 120 is located, and the auxiliary electrode 170 may be located on the insulating layer 160. In this case, the state in which the insulating layer 160 is laminated on the substrate 110 may become a wiring substrate. More specifically, the insulating layer 160 is a material having insulation and flexibility such as polyimide (PI), PET, PEN, etc., and may form an integral body with the substrate 110 to form a single 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 disposed corresponding to the position of the first electrode 120. For example, the auxiliary electrode 170 may be in a dot shape and may be electrically connected to the first electrode 120 through the electrode hole 171 penetrating the insulating layer 160. The electrode hole 171 may be formed by filling a conductive substance in the through hole.

[0078] As Figure 2 or Figure 3a As shown, a conductive adhesive layer 130 is formed on one surface of the insulating layer 160, but the present invention is not necessarily limited thereto. 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 in which the conductive adhesive layer 130 is disposed on the substrate 110 without the insulating layer 160 may also be employed. In the structure in which the conductive adhesive layer 130 is disposed on the substrate 110, the conductive adhesive layer 130 may function as an insulating layer.

[0079] The conductive adhesive layer 130 may be a layer having adhesiveness and conductivity. For this purpose, a conductive substance and an adhesive substance may be mixed in the conductive adhesive layer 130. In addition, the conductive adhesive layer 130 has flexibility, whereby the display device exhibits a flexible function.

[0080] As an example of this, 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 connection to each other in the Z direction penetrating the thickness and have point insulation in the horizontal X-Y 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 member, and only specific portions have conductivity due to the anisotropic conductive medium when heat and pressure are applied. Hereinafter, the case where heat and pressure are applied to the anisotropic conductive film will be described, but other methods may also be used to make a local portion of the anisotropic conductive film conductive. For example, the above method may be applying any one of the heat and pressure or UV curing, etc.

[0082] In addition, for example, the anisotropic conductive medium may be a conductive sphere or a conductive particle. For example, the anisotropic conductive film is a thin film in the form of mixing conductive spheres into an insulating substrate member, and only specific portions have conductivity due to the conductive spheres when heat and pressure are applied. The anisotropic conductive film may be in a state where particles including a plurality of conductive substances as cores are coated with an insulating film made of a polymer material. In this case, the insulating film of the portion to which heat and pressure are applied is broken and thus has conductivity through the cores. At this time, the cores may be deformed to form layers that contact each other in the thickness direction of the thin film. As a more specific example, heat and pressure are applied to the entire anisotropic conductive film, and electrical connection portions in the Z-axis direction are formed due to the height difference of the objects bonded through the anisotropic conductive film.

[0083] As another example, the anisotropic conductive film may be in a state of including a plurality of particles in which a conductive substance coats an insulating core. In this case, the portion to which heat and pressure are applied has conductivity in the thickness direction of the thin film due to the deformation (pressing) of the conductive substance. In addition, as another example, it may also be a form in which the conductive substance penetrates the insulating substrate member in the Z-axis direction and has conductivity in the thickness direction of the thin film. In this case, the conductive substance may have a pointed end.

[0084] The anisotropic conductive film may be a fixed array anisotropic conductive film (fixed array ACF) formed in a form in which conductive spheres are inserted into one surface of an insulating substrate member. More specifically, the insulating substrate member is formed of an adhesive substance, the conductive spheres are centrally arranged at the bottom of the insulating substrate member, and if heat and pressure are applied to the substrate member, it deforms together with the conductive spheres and has conductivity in the vertical direction.

[0085] However, the present invention is not necessarily limited thereto. The anisotropic conductive film may be in a form in which conductive spheres are randomly mixed into an insulating substrate member, or may be configured as a plurality of layers with conductive spheres arranged in any layer (double-ACF), etc.

[0086] An anisotropic conductive paste is a combined form of a paste and conductive spheres, which can be a paste with conductive spheres mixed in an insulating and adhesive substrate. Additionally, a solution containing conductive particles can be a solution in the form of containing conductive particles or nanoparticles.

[0087] Refer back to Figure 3a , the second electrode 140 is spaced apart from the auxiliary electrode 170 and is 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, after forming the conductive adhesive layer 130 while the auxiliary electrode 170 and the second electrode 140 are located on the insulating layer 160, the semiconductor light-emitting element 150 is connected in a flip-chip form by applying heat and pressure, the semiconductor light-emitting element 150 is electrically connected to the first electrode 120 and the second electrode 140.

[0089] Refer to Figure 4 , the semiconductor light-emitting element can be a light-emitting element of the flip-chip type.

[0090] For example, the semiconductor light-emitting element includes a p-type electrode 156, a p-type semiconductor layer 155 on which the p-type electrode 156 is formed, 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 spaced apart from the p-type electrode 156 in the horizontal direction. In this case, the p-type electrode 156 can be electrically connected to the auxiliary electrode 170 shown in FIG. 3 through the conductive adhesive layer 130, and the n-type electrode 152 can be electrically connected to the second electrode 140.

[0091] Refer back to Figure 2 , Figure 3a and Figure 3b , the auxiliary electrode 170 is formed long 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 inside of the conductive adhesive layer 130 by heat and pressure. As a result, only the portions between the p-type electrode 156 and the auxiliary electrode 170 of the semiconductor light-emitting element 150, and between the n-type electrode 152 and the second electrode 140 of the semiconductor light-emitting element 150 are conductive, while the remaining portions are not pressed by the semiconductor light-emitting element and thus are not conductive. As described above, the conductive adhesive layer 130 not only binds 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 on the light-emitting element array.

[0094] The light-emitting element array may include a plurality of semiconductor light-emitting elements having different self-luminance values. Each semiconductor light-emitting element 150 constitutes a unit pixel and is electrically connected to the 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 column, and the semiconductor light-emitting elements in each column may be electrically connected to any one of the plurality of first electrodes.

[0095] In addition, since the semiconductor light-emitting element is connected in a flip-chip form, a semiconductor light-emitting element grown on a transparent dielectric substrate can be used. In addition, the semiconductor light-emitting element may be, for example, a nitride semiconductor light-emitting element. Since the brightness of the semiconductor light-emitting element 150 is excellent, even if the size is small, a single unit pixel can be formed.

[0096] As shown in FIG. 3, a partition wall 190 may be formed between the semiconductor light-emitting elements 150. In this case, the partition wall 190 serves to separate the individual unit pixels from each other and may be formed integrally with the conductive adhesive layer 130. For example, by inserting the semiconductor light-emitting element 150 into the anisotropic conductive film, the base member of the anisotropic conductive film can form the partition wall.

[0097] In addition, if the base member of the anisotropic conductive film is black, no additional black insulator is required, and the partition wall 190 can have a reflective property while increasing the contrast.

[0098] As another example, a reflective partition wall may be additionally provided as the partition wall 190. In this case, the partition wall 190 may include a black or white insulator according to the purpose of the display device. In the case of a partition wall using a white insulator, it can have the effect of improving reflectivity, and in the case of a partition wall using a black insulator, it can increase the contrast while having reflective characteristics.

[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 181 or a green phosphor 182 that constitutes an individual pixel.

[0100] That is, at the position where a red unit pixel is formed, a red phosphor 181 that can convert blue light into red R light may be stacked on the blue semiconductor light-emitting element, and at the position where a green unit pixel is formed, a green phosphor 182 that can convert blue light into green G light may be stacked on the blue semiconductor light-emitting element. In addition, only the blue semiconductor light-emitting element may be used alone in the portion where a blue unit pixel is formed. In this case, the red R, green G, and blue B unit pixels may form one pixel. More specifically, one color of phosphor may be stacked along each line of the first electrode 120. Therefore, in the first electrode 120, one line may be an electrode that controls one color. That is, along the second electrode 140, red R, green G, and blue B may be arranged in sequence, whereby a unit pixel can be realized.

[0101] However, the present invention is not necessarily limited thereto. As an alternative to the phosphor, the red R, green G, and blue B unit pixels may also be realized by combining the semiconductor light-emitting element 150 and quantum dots (QDs).

[0102] In addition, in order to improve the contrast, a black matrix 191 may be disposed between the respective phosphor layers. That is, such a black matrix 191 can improve the contrast between light and dark.

[0103] However, the present invention is not necessarily limited thereto, and other structures for realizing blue, red, and green may be used.

[0104] Referring to Figure 5a , each semiconductor light-emitting element 150 may be realized by a high-output light-emitting element that emits various lights such as blue by using gallium nitride (GaN) as a main material and adding indium (In) and / or aluminum (Al).

[0105] In this case, the semiconductor light-emitting elements can be red, green, and blue semiconductor light-emitting elements to respectively implement sub-pixels. For example, the red, green, and blue semiconductor light-emitting elements R, G, and B can be alternately arranged, and the red (Red), green (Green), and blue (Blue) sub-pixels form a pixel through the red, green, and blue semiconductor light-emitting elements. Thus, full-color display can be achieved.

[0106] Referring to Figure 5b , the semiconductor light-emitting elements can include white light-emitting elements W each provided with a yellow phosphor layer. In this case, in order to implement sub-pixels, a red phosphor layer 181, a green phosphor layer 182, and a blue phosphor layer 183 can be provided on the white light-emitting element W. Additionally, sub-pixels can be implemented by using color filters that repeatedly cycle through red, green, and blue on such white light-emitting elements W.

[0107] Referring to Figure 5c , a structure in which a red phosphor layer 181, a green phosphor layer 182, and a blue phosphor layer 183 are provided on an ultraviolet light-emitting element UV can also be adopted. As described above, the semiconductor light-emitting elements can not only use visible light but also be used in the entire region including ultraviolet light UV, and the semiconductor light-emitting elements can be extended to use ultraviolet light UV as an excitation source for the upper phosphor.

[0108] Referring back to this example, the semiconductor light-emitting elements are located on a conductive adhesive layer and form sub-pixels in the display device. Since the semiconductor light-emitting elements have excellent brightness, even if they are small in size, individual sub-pixels can be formed.

[0109] The size of a single semiconductor light-emitting element 150 as described above can be, for example, an element with a variable length of 80 μm or less and having a rectangular or square shape. In the case of a rectangle, it can have a size of 20X80 μm or less.

[0110] Additionally, even if a square semiconductor light-emitting element 150 with a side length of 10 μm is used as a sub-pixel, sufficient brightness for implementing the display device can be achieved.

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

[0112] Therefore, in this case, a flexible display device with high-quality image quality above HD can be achieved.

[0113] The display device using the above semiconductor light-emitting element can be manufactured by a new form of manufacturing method. Hereinafter, with reference to Figure 6 the manufacturing method will be described.

[0114] Figure 6 It is a cross-sectional view showing a manufacturing method of a display device using a semiconductor light-emitting element of the present invention.

[0115] As Figure 6 shown, first, 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 laminated on the wiring substrate 110, and the first electrode 120, the auxiliary electrode 170, and the second electrode 140 are disposed on the wiring substrate 110. In this case, the first electrode 120 and the second electrode 140 can be disposed in directions orthogonal to each other. In addition, in order to realize a flexible display device, the wiring substrate 110 and the insulating layer 160 may include glass or polyimide (PI), respectively.

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

[0117] Next, a temporary substrate 112 on which a plurality of semiconductor light-emitting elements 150 corresponding to the positions of the auxiliary electrode 170 and the second electrode 140 and constituting individual pixels are disposed is arranged so 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 a growth substrate on which the semiconductor light-emitting elements 150 grow, and it can be a sapphire substrate or a silicon substrate.

[0119] When the semiconductor light-emitting elements are formed in units of wafers, they can be effectively used for a display device by having intervals and dimensions that can realize the display device.

[0120] Next, the wiring substrate and the temporary substrate 112 are thermocompression bonded. For example, the wiring substrate and the temporary substrate 112 can be thermocompression bonded using an ACF head. The wiring substrate and the temporary substrate 112 are joined (bonded) by the thermocompression bonding. Due to the characteristics of the anisotropic conductive film having conductivity, conductivity is present only in the portion between the semiconductor light-emitting element 150, the auxiliary electrode 170, and the second electrode 140 through the thermocompression bonding, whereby the electrode and the semiconductor light-emitting element 150 can be electrically connected. At this time, the semiconductor light-emitting element 150 is inserted into the interior of the anisotropic conductive film, whereby a partition wall can be formed 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 a laser lift-off (LLO) method or a chemical lift-off (CLO) method.

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

[0123] In addition, a step of forming a phosphor layer on one surface of the semiconductor light-emitting element 150 can also be included. For example, the semiconductor light-emitting element 150 can be a blue semiconductor light-emitting element that emits blue B light, and a red phosphor or a green phosphor for converting such blue B light into the color of a unit pixel can be formed in a layer form on one surface of the blue semiconductor light-emitting element.

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

[0125] In addition, in the modification examples or embodiments described below, the same or similar constituent elements as those in the foregoing examples are given the same or similar reference numerals, and the description thereof is replaced with the first description.

[0126] Figure 7 is a perspective view showing another embodiment of the display device using the semiconductor light-emitting element of the present invention, Figure 8 is Figure 7 a cross-sectional view taken along line D-D of Figure 9 is showing Figure 8 a conceptual diagram of the vertical semiconductor light-emitting element of

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

[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. In addition, any material having insulation and flexibility can be used.

[0130] The first electrode 220 is located on the substrate 210 and may be formed in a long bar shape in one direction. The first electrode 220 can be implemented to function as a data electrode.

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

[0132] If the anisotropy conductive film is positioned after the first electrode 220 is located on the substrate 210, and then the semiconductor light-emitting element 250 is connected by heat and pressure, the semiconductor light-emitting element 250 is electrically connected to the first electrode 220. At this time, preferably, the semiconductor light-emitting element 250 is disposed on the first electrode 220.

[0133] As described above, the electrical connection is generated because when heat and voltage are applied, the local part of the anisotropy conductive film has conductivity in the thickness direction. Therefore, the anisotropy conductive film is divided into a part having conductivity in the thickness direction and a part having no conductivity.

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

[0135] As described above, the semiconductor light-emitting element 250 is located on the conductive adhesive layer 230, whereby a single pixel is formed in the display device. Since the semiconductor light-emitting element 250 has excellent brightness, a single unit pixel can be formed even with a smaller size. The size of the single semiconductor light-emitting element 250 as described above can be, for example, a rectangle or a square with a side length of 80 μm or less. In the case of a rectangle, for example, the size can be 20X80 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 the vertical semiconductor light-emitting elements. The plurality of second electrodes 240 are arranged in a direction intersecting the length direction of the first electrode 220 and are electrically connected to the vertical semiconductor light-emitting element 250.

[0138] Referring to Figure 9 , such a vertical semiconductor light-emitting element 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 the conductive adhesive layer 230, and the upper n-type electrode 252 can be electrically connected to the second electrode 240 described later. Since such a vertical semiconductor light-emitting element 250 can arrange electrodes vertically, it has a great advantage of being able to reduce the size.

[0139] Referring back to Figure 8 , a phosphor layer 280 can be formed on one surface 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 can be provided for converting such blue B light into the color of a unit pixel. In this case, the phosphor layer 280 can be a red phosphor 281 and a green phosphor 282 that constitute individual pixels.

[0140] That is, at the position where a red unit pixel is formed, a red phosphor 281 that can convert blue light into red R light can be laminated on the blue semiconductor light-emitting element. At the position where a green unit pixel is formed, a green phosphor 282 that can convert blue light into green G light can be laminated on the blue semiconductor light-emitting element. In addition, in the part 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 one pixel.

[0141] However, the present invention is not necessarily limited thereto. As described above, in a display device using a light-emitting element of the flip chip type, other structures for realizing blue, red, and green can be used.

[0142] Referring back 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 can be located between the columns of the semiconductor light-emitting elements 250.

[0143] Since the distance between the semiconductor light-emitting elements 250 forming 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 having a long bar shape in one direction and can be arranged in a direction perpendicular to the first electrode.

[0145] In addition, the second electrode 240 and the semiconductor light-emitting elements 250 can be electrically connected through connection electrodes protruding from the second electrode 240. More specifically, the connection electrodes can be n-type electrodes of the semiconductor light-emitting elements 250. For example, the n-type electrodes are formed as ohmic electrodes for ohmic contact, and the second electrode covers at least a part of the ohmic electrodes by printing or deposition. Thus, the second electrode 240 and the n-type electrodes of the semiconductor light-emitting elements 250 can be electrically connected.

[0146] Referring back to Figure 8 , the second electrode 240 can be located on the conductive adhesive layer 230. Depending on the situation, a transparent insulating layer (not shown) including silicon oxide (SiOx) or the like can be formed on the substrate 210 on which the semiconductor light-emitting elements 250 are formed. When the second electrode 240 is positioned after the transparent insulating layer is formed, the second electrode 240 is located on the transparent insulating layer. In addition, the second electrode 240 can also 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 make the second electrode 240 located on the semiconductor light-emitting elements 250, there is a problem that the adhesion between the ITO material and the n-type semiconductor layer is poor. Therefore, in the present invention, the second electrode 240 is located between the semiconductor light-emitting elements 250, thereby having the advantage that a transparent electrode such as ITO can be not used. Therefore, the light extraction efficiency can be improved by using a conductive material having good adhesion to the n-type semiconductor layer as the horizontal electrode, without being limited by the selection of transparent materials.

[0148] Referring back to Figure 8, the partition wall 290 may be located between the semiconductor light-emitting elements 250. That is, in order to separate the semiconductor light-emitting elements 250 forming individual pixels, the partition wall 290 may be disposed between the vertical semiconductor light-emitting elements 250. In this case, the partition wall 290 may function to separate each unit pixel from each other, and the partition wall 290 may be formed integrally with the conductive adhesive layer 230. For example, by inserting the semiconductor light-emitting element 250 into the anisotropic conductive film, the partition wall may be formed by the base member of the anisotropic conductive film.

[0149] In addition, if the base member of the anisotropic conductive film is black, even without an additional black insulator, the partition wall 290 may have reflective characteristics while increasing the contrast.

[0150] As another example, a reflective partition wall may be additionally provided as the partition wall 190. The partition wall 290 may include a black or white insulator according to the purpose of the display device.

[0151] If, when the second electrode 240 is directly above the conductive adhesive layer 230 between the semiconductor light-emitting elements 250, the partition wall 290 may be located between each vertical semiconductor light-emitting element 250 and the second electrode 240. Therefore, by using the semiconductor light-emitting element 250, a single unit pixel can also be formed in a small size, and since the distance between the semiconductor light-emitting elements 250 becomes relatively large enough, the second electrode 240 can be located between the semiconductor light-emitting elements 250, and there is an effect of realizing a flexible display device with HD image quality.

[0152] In addition, as Figure 8 shown, in order to improve the contrast, a black matrix 291 may be disposed between the respective phosphors. That is, such a black matrix 291 can improve the light and dark contrast.

[0153] As described above, in the case of a large-size high-pixel display device using semiconductor light-emitting elements, the semiconductor light-emitting elements grown on the growth substrate need to be assembled or transferred to a new substrate. For example, from the current technical level, the growth substrate may be a 12-inch wafer, and thus transfer may be repeated multiple times.

[0154] For example, the assembly or transfer process is a process of arranging a very large number of semiconductor light-emitting elements together on a new substrate. During the arrangement process, it may occur that the semiconductor light-emitting elements are arranged at other positions different from the set positions, resulting in arrangement errors.

[0155] In addition, after the assembly or transfer, a wiring process for electrically connecting the semiconductor light-emitting elements is performed. When the range of the alignment error exceeds a specified specification (Spec) range, the semiconductor light-emitting elements may cause defects such as short circuits or open circuits.

[0156] Through experiments, it is necessary to manage the range of the alignment error to the level of ±3 μm, which is the most important core factor in the production yield of the display panel.

[0157] However, in reality, managing the alignment error becomes a factor that increases the manufacturing cost, such as additional equipment management and increased working hours. Next, with reference to Figures 10 to 22 , other embodiments of the present invention for solving the above problems will be described in detail.

[0158] Figure 10 It is a flowchart showing a method for manufacturing a display device using semiconductor light-emitting elements according to another embodiment of the present invention.

[0159] First, a semiconductor light-emitting structure is formed on a first substrate (or growth substrate) (S1010). Although, in the present invention, the semiconductor light-emitting structure may be a horizontal semiconductor light-emitting structure or a vertical semiconductor light-emitting structure, hereinafter, the case of forming a horizontal semiconductor light-emitting structure will be described. Next, with reference to Figure 13 The detailed formation method will be described.

[0160] After that, a multi-passivation layer is formed on the semiconductor light-emitting structure formed on the first substrate (S1020). The multi-passivation layer is composed of a first passivation layer and a second passivation layer, and a part of the region of the first passivation layer formed on the semiconductor light-emitting structure is in a state of being removed before the second passivation layer is formed. In the following content of this specification, the semiconductor light-emitting structure formed with the multi-passivation layer will be defined as a semiconductor light-emitting element and described.

[0161] Next, the semiconductor light-emitting element formed on the first substrate is separated from the first substrate (S1030).

[0162] For example, the method of separating the semiconductor light-emitting element from the first substrate is roughly divided into two types. The first is a method of directly transferring the semiconductor light-emitting element on the first substrate to the second substrate. In this case, since it is a transfer between substrates, the interval between the semiconductor light-emitting elements after transfer remains the same as the interval on the first substrate before transfer. However, for example, during the transfer process based on a flexible film used for transfer between substrates, an alignment error of the semiconductor light-emitting elements may occur.

[0163] The second method is a case where individual semiconductor light-emitting elements are separated from the first substrate and exist separately.

[0164] After that, the separated semiconductor light-emitting elements are assembled onto the second substrate (S10400).

[0165] The assembly refers to the process in which the semiconductor light-emitting elements move from the first substrate to the second substrate and can be mixed with transfer. As described above, in the case of substrate-to-substrate transfer, the second substrate can also be a donor substrate for transfer or a wiring substrate on which wiring is provided so that it can be directly used as a display panel.

[0166] The transfer process is a process of transferring the semiconductor light-emitting elements on the first substrate to the second substrate using an adhesive film or the like, just like stamping. For example, such a process is called a stamping process.

[0167] The stamping process may include a step of performing alignment. For example, it is performed by horizontally moving either the first substrate or the second substrate relative to the other substrate and then vertically moving it relative to the other substrate. After that, it is checked whether the semiconductor light-emitting elements on the first substrate and the assembly positions on the second substrate corresponding to the semiconductor light-emitting elements overlap by using a camera sensor or the like, and if they overlap, the semiconductor light-emitting elements are assembled in accordance with the positions. However, there may be a slight alignment error in this case.

[0168] During the transfer process, the adhesive film can also use an anisotropic conductive film to impart conductivity between the substrate and the semiconductor light-emitting elements.

[0169] In order to selectively transfer only a part of the semiconductor light-emitting elements grown on the first substrate, a method such as laser lift-off (LLO) can be used, which selectively separates the elements by applying a laser to the opposite side of the substrate on which the elements are grown.

[0170] For example, as another method of assembling the semiconductor light-emitting elements onto the second substrate, a self-assembly process can be performed.

[0171] The self-assembly process is a process in which a very large number of semiconductor light-emitting elements are assembled onto the second substrate by the force of an electromagnetic field in a chamber filled with a fluid.

[0172] The second substrate can be an assembly substrate formed with assembly grooves for self-assembly of the semiconductor light-emitting elements. Assembly electrodes are provided below the assembly grooves, and the assembly substrate can be located in a chamber filled with a fluid.

[0173] For example, since the semiconductor light-emitting element floating in the fluid includes a magnetic layer, it can be moved in the direction of the assembly substrate by an assembly device having a magnet that acts on the upper part of the assembly substrate. That is, the semiconductor light-emitting element in the chamber can be moved toward the assembly device by the magnetic field generated by the assembly device.

[0174] The assembly substrate formed with assembly grooves can be located in the direction of movement toward the assembly device, and the semiconductor light-emitting element can be in contact with the assembly grooves.

[0175] In this case, the semiconductor light-emitting element in contact with the assembly grooves is fixed by an electric field applied from an assembly electrode formed at the lower part of the assembly grooves.

[0176] By the self-assembly method based on the electric field and the magnetic field, the time required for assembling the semiconductor light-emitting element to the substrate can be sharply shortened.

[0177] However, there is an assembly interval between the semiconductor light-emitting elements assembled to the assembly grooves, and an assembly interval above a specified reference value in the assembly interval may cause poor electrode formation during the wiring process.

[0178] After that, a wiring process (S1050) is performed on the semiconductor light-emitting element assembled to the second substrate. The wiring process includes a process of forming an insulating layer and flattening the insulating layer and an etching process for forming electrodes.

[0179] However, in view of the overall spirit of this specification, deleting and changing Figure 10 a part of the steps of the flowchart shown also fall within the protection scope of the present invention at a level understandable by those skilled in the art.

[0180] Figure 11 Specifically represents the process of forming Figure 10 the multi-passivation layer.

[0181] Since the passivation layer is continuously formed after the semiconductor light-emitting structure is formed on the first substrate, the passivation layer may not be formed under the semiconductor light-emitting structure. However, this is only an example case, and the present invention is not limited thereto.

[0182] In addition, the passivation layer can be formed by treating inorganic insulators such as silicon dioxide and aluminum oxide through plasma enhanced chemical vapor deposition (PECVD), low pressure chemical vapor deposition (LPCVD), sputtering deposition methods, etc., or can be formed by treating organic substances such as photoresist and polymer materials through spin coating method.

[0183] First, a first passivation layer is formed on the semiconductor light-emitting structure formed on the first substrate (S1021). The semiconductor light-emitting structure described later includes a first conductivity type semiconductor layer, an active layer, a second conductivity type semiconductor layer, a first conductivity type electrode, and a second conductivity type electrode.

[0184] The first passivation layer is formed on both the side and the upper part of the semiconductor light-emitting structure. The first conductivity type electrode formed on the first conductivity type semiconductor layer and the first conductivity type electrode formed on the second conductivity type semiconductor layer are located on the upper part of the semiconductor light-emitting structure.

[0185] After that, a process of selectively removing the first conductivity type electrode located on the upper part of the semiconductor light-emitting structure and the first passivation layer formed on the second conductivity type electrode is performed (S1022).

[0186] The process of selective removal (S1022) may include a photolithography process and an etching process.

[0187] For example, the etching process refers to wet etching or dry etching.

[0188] After the selective removal process, the first passivation layer is located on the side of the semiconductor light-emitting structure and in the area of the upper part of the semiconductor light-emitting structure except for the first conductivity type electrode and the second conductivity type electrode.

[0189] After that, a second passivation layer is formed on the semiconductor light-emitting structure (S1023).

[0190] Therefore, the first passivation layer and the second passivation layer are sequentially disposed on the side surface of the semiconductor light-emitting structure. In addition, in the upper region of the semiconductor light-emitting structure, only the second passivation layer is formed on the upper portions of the first conductive type electrode and the second conductive type electrode, while the first passivation layer and the second passivation layer can be sequentially disposed in a region other than the first conductive type electrode and the second conductive type electrode.

[0191] On the other hand, in the case where the first passivation layer and the second passivation layer are different substances from each other, for example, the first etching ratio of the first passivation layer may be smaller than the second etching ratio of the second passivation layer.

[0192] The etching ratio is a ratio representing the degree of etching during a unit time period. In the case of wet etching, the etching ratio may vary depending on the chemical solution for the reaction, and in the case of dry etching, the etching ratio may vary depending on the type of ion gas for the reaction. In the case of the present invention, it refers to the case where the first etching ratio of the first passivation layer is smaller than the second etching ratio of the second passivation layer corresponding to the etching method performed.

[0193] In addition, in the case where the first passivation layer and the second passivation layer are the same substance, for example, the second thickness of the second passivation layer may be thinner than the first thickness of the first passivation layer.

[0194] The difference in the etching ratio or thickness between the first passivation layer and the second passivation layer provides an environment in which it is easy to selectively remove only the passivation layer formed on the upper portions of the first conductive type electrode and the second conductive type electrode in the semiconductor light-emitting element. The detailed content thereof will be described with reference to Figures 17 to 20 In addition, the substances of the first passivation layer and the second passivation layer can be selected differently so that the first refractive index of the first passivation layer and the second refractive index of the second passivation layer are different.

[0195] Accordingly, when the semiconductor light-emitting element is driven, the light emitted from the side surface of the element is reflected back into the element due to the multiple passivation layers having different refractive indices from each other, thereby improving the light-emitting efficiency.

[0196] On the other hand, from the overall spirit of this specification, deleting and changing Figure 11 a part of the steps of the shown flowchart at a level understandable to those skilled in the art also fall within the protection scope of the present invention.

[0197] Figure 12 Specifically represents the execution of Figure 10 The flowchart of the process of the wiring process.

[0198] First, an insulating layer is formed on the semiconductor light-emitting element assembled to the second substrate (S1051). The insulating layer surrounds the side and upper portions of the semiconductor light-emitting element. On the other hand, for example, the insulating layer can be deposited by a method such as CVD (Chemical Vapor Deposition), or can be coated by spin-coating after coating an insulating solution on the substrate.

[0199] In addition, the insulating layer can be an organic insulating layer, and preferably can be a photosensitive organic insulating layer. The photosensitive organic insulating layer can be formed by spraying or spin-coating a positive tone photosensitizer such as photosensitive acrylate or PAC (Photo Active Compounds). The positive tone photosensitizer refers to a photosensitizer in which the exposed area is developed and removed.

[0200] In addition, in the case of the insulating layer formed on the upper portion of the semiconductor light-emitting element, since there is a probability of relative protrusion, a planarization process can be additionally performed on the insulating layer (S1052). For example, the planarization process refers to CMP (Chemical Mechanical Polishing), which can perform chemical and mechanical polishing steps.

[0201] After that, in order to form wiring electrodes, the passivation layer formed outside the insulating layer and the semiconductor light-emitting element is selectively removed (S1053). The removal of the passivation layer can remove both the first passivation layer and the second passivation layer formed on the upper portion of the semiconductor light-emitting element, or can selectively remove only the second passivation layer. However, even after the removal process, a passivation layer in contact with the insulating layer still remains on the side of the semiconductor light-emitting element.

[0202] In the case of removing only the second passivation layer, only the first conductive type electrode and the second conductive type electrode of the semiconductor light-emitting element are exposed to the outside. The removal step can perform a photolithography process and an etching process.

[0203] After that, a first electrode electrically connected to the exposed first conductive type electrode and a second electrode electrically connected to the exposed second conductive type electrode are formed (S1054).

[0204] Since there is still a passivation layer in other regions of the semiconductor light-emitting element except for the exposed regions, even if the positions where the first electrode and the second electrode are formed are inaccurate and only a partial region is in contact with the conductive type electrodes of the semiconductor light-emitting element, a short circuit phenomenon between different semiconductor layers in the semiconductor light-emitting element will not occur.

[0205] On the other hand, from the overall spirit of this specification, deleting and changing Figure 12 a part of the steps of the flowchart shown also fall within the protection scope of the present invention.

[0206] Figure 13 represents a cross-sectional view of a semiconductor light-emitting structure formed on Figure 10 a first substrate.

[0207] As Figure 13 shown, the semiconductor light-emitting structure 1010 is formed on the first substrate 1001 and includes a first-conductivity-type semiconductor layer 1011, an active layer 1012, a second-conductivity-type semiconductor layer 1013, a first-conductivity-type electrode 1015, and a second-conductivity-type electrode 1014. The semiconductor light-emitting structure is a horizontal structure, exemplifying a structure in which a first-conductivity-type electrode 1015 is formed in a region where a part of the second-conductivity-type semiconductor layer 1013 and a part of the active layer 1012 are etched and exposed in the first-conductivity-type semiconductor layer 1011. However, the present invention is not limited thereto, and various horizontal mesa structures and vertical structures can be formed.

[0208] In addition, the first substrate 1001 may include a material having a light-transmitting property, such as any one of sapphire (Al2O3), GaN, ZnO, and AlO.

[0209] In addition, the first substrate 1001 may be formed of a material suitable for semiconductor material growth and a carrier wafer. In addition, the first substrate 1001 may be formed of a material having excellent thermal conductivity and may include a conductive substrate or an insulating substrate. For example, an SiC substrate or at least one of Si, GaAs, GaP, InP, and Ga2O3 having a higher thermal conductivity than a sapphire (Al2O3) substrate can be used, but it is not limited thereto.

[0210] Furthermore, the first-conductivity-type semiconductor layer 1011 grown on the first substrate 1001 is an n-type semiconductor layer, which may be a nitride semiconductor layer such as n-GaN, and the second-conductivity-type semiconductor layer 1013 may be a p-type semiconductor layer. However, the present invention is not necessarily limited thereto. As an example, the first-conductivity-type semiconductor layer 1011 may be p-type and the second-conductivity-type semiconductor layer 1013 may be n-type.

[0211] In addition, according to another embodiment of the present invention, the first conductivity type semiconductor layer 1011 and the second conductivity type semiconductor layer 1013 can be formed by injecting impurities into an intrinsic or doped semiconductor substrate. In addition, the p-n junction region formed by injecting the impurities can also play the same role as the active layer 1012. The listed items for the first conductivity type semiconductor layer 1011, the second conductivity type semiconductor layer 1013, and the active layer 1012 are only examples, and the present invention is not limited thereto.

[0212] In addition, as Figure 13 shown, the first conductivity type electrode 1015 is formed on the upper part of the first conductivity type semiconductor layer. Therefore, in order to form the first conductivity type electrode 1015, a part of the stacked semiconductor layer can be patterned by a photolithography process, and after etching this region, a process of depositing a conductive electrode can be performed.

[0213] The first conductivity type electrode 1015 is in electrical contact with the first conductivity type semiconductor layer 1011 and can be formed of one or more metal layers. The first conductivity type electrode 1015 can include any one or more of ITO, chromium (Cr), titanium (Ti), and nickel silver (Ni-Ag), and form an ohmic contact layer having ohmic contact characteristics with the first conductivity type semiconductor layer 1011.

[0214] In addition, the second conductivity type electrode 1014 formed on the second conductivity type semiconductor layer 1013 can also be formed of one or more metal layers in the same manner as the first conductivity type electrode 1015. The second conductivity type electrode 1014 can include any one or more of ITO, chromium (Cr), titanium (Ti), and nickel silver (Ni-Ag) and form an ohmic contact layer having ohmic contact characteristics with the second conductivity type semiconductor layer 1013.

[0215] In addition, for the self-assembled semiconductor light-emitting element, a magnetic layer can be formed under the first conductivity type electrode 1015 or the second conductivity type electrode 1014. Or, for example, the magnetic layer itself formed on the upper part of the first conductivity type semiconductor layer 1011 or the second conductivity type semiconductor layer 1013 can also be used as a conductive electrode.

[0216] Figure 14 is a cross-sectional view after forming the first passivation layer in the Figure 13 semiconductor light-emitting structure.

[0217] As Figure 14As shown, the first passivation layer 1021 is formed on the side and upper part of the semiconductor light-emitting structure. Since the semiconductor light-emitting structure is formed on the first substrate 1001, the first passivation layer 1021 is also continuously formed. Therefore, the first passivation layer 1021 may not be formed on the lower part of the semiconductor light-emitting structure. However, this is only an example, and the present invention is not limited thereto.

[0218] Specifically, in Figure 14 , both side surfaces of the active layer 1012 and the second-conductive-type semiconductor layer 1013 of the semiconductor light-emitting structure are in contact with the first passivation layer 1021, while both side surfaces and the upper part of the first-conductive-type semiconductor layer 1011, the first-conductive-type electrode 1015, and the second-conductive-type electrode 1014 of the semiconductor light-emitting structure are in contact with the first passivation layer 1021. However, this is only an example, and the present invention is not limited thereto.

[0219] Figure 15 is a cross-sectional view showing after selectively removing only the first passivation layer formed on the upper part of the conductive-type electrode of the semiconductor light-emitting structure. Figure 14

[0220] The selective removal can be performed by a process of patterning a part of the upper part of the semiconductor light-emitting element through a photolithography process and then etching the region.

[0221] As Figure 15 shown, in the semiconductor light-emitting structure formed on the first substrate 1001, the regions where the first passivation layer 1021 is formed are the side surfaces of the first-conductive-type semiconductor layer 1011, the active layer 1012, the second-conductive-type semiconductor layer 1013, the first-conductive-type electrode 1015, and the second-conductive-type electrode 1015, and a part of the upper part of the first-conductive-type semiconductor layer 1011. That is, only the upper part of the conductive-type electrode for electrically connecting the semiconductor light-emitting structure has the first passivation layer 1021 removed.

[0222] Figure 16 is a cross-sectional view of a semiconductor light-emitting element in which a second passivation layer is formed in the Figure 15 semiconductor light-emitting structure.

[0223] The second passivation layer 1022 is formed outside the first passivation layer 1021 that has been formed on the semiconductor light-emitting structure, and the second passivation layer 1022 is also formed on the upper parts of the first-conductive-type electrode 1015 and the second-conductive-type electrode 1014.

[0224] Therefore, only the second passivation layer 1022 is formed on the upper portions of the first-conductive-type electrode 1015 and the second-conductive-type electrode 1014, and the first passivation layer 1021 and the second passivation layer 1022 are sequentially disposed on the remaining surfaces except for the lower surface of the semiconductor light-emitting structure.

[0225] Figure 17 is a cross-sectional view after performing a wiring process on a semiconductor light-emitting element of Figure 16 .

[0226] To perform the wiring process, a process of separating a semiconductor light-emitting element having a multi-passivation layer formed thereon from a first substrate and assembling it on a second substrate must be performed in advance. As described above, the separation and assembly steps can be performed by a substrate-to-substrate transfer method or a self-assembly method.

[0227] As Figure 17 shown, the semiconductor light-emitting element 1700 including the first-conductive-type semiconductor layer 1011, the active layer 1012, the second-conductive-type semiconductor layer 1013, the first-conductive-type electrode 1015, the second-conductive-type electrode 1014, the first passivation layer 1021, and the second passivation layer 1022 is located on the second substrate 1041.

[0228] The first electrode 1052 and the second electrode 1053 are located in a partial region on the upper portions of the first-conductive-type electrode 1015 and the second-conductive-type electrode 1014 of the semiconductor light-emitting element, and an insulating layer 1051 is formed on the upper portion and the side surface of the element to prevent the electrodes from being electrically connected to other regions of the semiconductor light-emitting element.

[0229] In addition, Figure 17 is a cross-sectional view of the semiconductor light-emitting element after performing the wiring process described in Figure 12 , showing a case where a planarization process and electrodes are formed after forming an insulating layer on the semiconductor light-emitting element.

[0230] The thickness of the insulating layer 1051 is sufficiently thick compared to the height of the assembled semiconductor light-emitting element 1700, and the insulating layer 1051 is formed so that the upper portion of the semiconductor light-emitting element 1700 is not exposed to the surface. Thereafter, in order to expose a specified region on the upper portions of the first-conductive-type electrode 1015 and the second-conductive-type electrode 1014, a light process and an etching process are performed on this region.

[0231] The first electrode 1052 and the second electrode 1053 for electrically connecting to the first-conductive-type electrode 1015 and the second-conductive-type electrode 1014 are formed in the exposed region. Thereafter, the insulating layer 1051 is re-coated to protect the electrodes 1052 and 1053. Therefore, strictly speaking, Figure 17The illustrated insulating layer 1051 may be composed of a first insulating layer before the electrode formation process and a second insulating layer for protecting the electrode after the electrode formation.

[0232] In addition, the etching process may be dry etching or wet etching. In the case of dry etching, for example, since anisotropic etching is mainly performed using an ion reaction gas in a plasma state, precise control of fine patterns and etching thickness can be achieved. In addition, in the case of wet etching, by using a chemical solution, the area contacted by the chemical solution is mainly isotropically etched.

[0233] Figure 17 The semiconductor light-emitting element 1700 shows a state where the first electrode 1052 and the second electrode 1053 are accurately connected to the first conductivity type electrode 1015 and the second conductivity type electrode 1014.

[0234] In the case of the semiconductor light-emitting element 1700, even when the electrodes 1052 and 1053 are formed at a position equivalent to the error distance due to alignment errors during assembly, the probability of occurrence of defects such as a short circuit is reduced.

[0235] The short-circuit defect refers to a phenomenon where, for example, when forming the first electrode in a semiconductor light-emitting element, electrical connection occurs not only in the first conductivity type electrode but also in other unintended regions such as the second conductivity type semiconductor layer of the semiconductor light-emitting element.

[0236] In the present invention, the main reason for the decrease in the probability of occurrence of the short-circuit defect is that, as Figure 11 explained, in the structure of the semiconductor light-emitting element, a multiple passivation layer is formed for the first time, and then the etching ratio of the passivation layer is differently selected or the thicknesses of the respective passivation layers are differently formed.

[0237] For example, in order to expose a partial region of the first conductivity type electrode 1015 of the semiconductor light-emitting element 1700, an etching process for selectively removing the second passivation layer 1022 surrounding the conductivity type electrode is performed. The etching process is performed at a position overlapping the first conductivity type electrode 1015 and the second conductivity type semiconductor layer 1011. If it is assumed that the structure does not have the first passivation layer 1021, the second conductivity type semiconductor layer 1011 region will also be exposed due to the etching process. Therefore, the probability of causing a short-circuit defect between the first conductivity type semiconductor layer 1011 and the second conductivity type semiconductor layer 1013 during electrode formation is relatively high.

[0238] In addition, for example, even in the structure with the first passivation layer 1021, if the first passivation layer 1021 is the same material as the second passivation layer 1022 and has a very thin thickness with the same etching ratio, it will be removed together during the etching process of the second passivation layer, which may cause a short - circuit defect when forming the electrodes.

[0239] The structure for preventing such short - circuit defects is particularly important in display devices that require transfer or assembly of semiconductor light - emitting elements. This is because only alignment errors can occur during transfer or assembly, and as smaller - sized semiconductor light - emitting elements are increasingly required for high - pixel displays, in such an environment, the alignment errors gradually increase the probability of causing short - circuit defects when forming electrodes. Therefore, the structure of a general semiconductor light - emitting element is not suitable, and a semiconductor light - emitting element structure that can selectively remove only the passivation layer formed in the conductive - type electrode region for electrical connection is needed. Therefore, the present invention can be regarded as an example of a semiconductor light - emitting element structure that meets the above requirements.

[0240] Figure 18 is Figure 16 Another cross - sectional view after performing a wiring process on the semiconductor light - emitting element.

[0241] Regarding the wiring process, Figure 17 compared with the wiring process of Figure 17 the thickness of the first insulating layer formed is different. In the wiring process of Figure 18 the thickness of the insulating layer can completely cover the upper part of the semiconductor light - emitting element, while in the wiring process of

[0242] the thickness of the first insulating layer (not shown) is formed at a level similar to the height of the upper part of the assembled semiconductor light - emitting element 1701. Then, the semiconductor light - emitting element 1701 is exposed to the surface by planarizing the first insulating layer. In addition, an etching process for removing the second passivation layer on the conductive - type electrodes 1014 and 1015 of the exposed semiconductor light - emitting element 1701 is performed. At this time, the etching process can be performed on the entire substrate without an additional light process.

[0243] As Figure 18 shown, the semiconductor light - emitting element 1701 after the wiring process includes a first - conductive - type semiconductor layer 1011, an active layer 1012, a second - conductive - type semiconductor layer 1013, a first - conductive - type electrode 1015, a second - conductive - type electrode 1014, a first passivation layer 1021, and a second passivation layer 1022, and is located on the second substrate 1041.

[0244] In addition, there are no first passivation layer 1021 and second passivation layer 1022 on the upper portions of the first conductivity type electrode 1015 and the second conductivity type electrode 1014 of the semiconductor light-emitting element 1701.

[0245] In addition, the first electrode 1052 and the second electrode 1053 are located in a partial area on the upper portions of the first conductivity type electrode 1015 and the second conductivity type electrode 1014 of the semiconductor light-emitting element 1701, and an insulating layer 1051 is formed on the upper portion and the side surface of the element so that the electrodes are not electrically connected to other areas of the semiconductor light-emitting element. The insulating layer 1051 is a concept that encompasses the first insulating layer, the second insulating layer, and the third insulating layer described in the Figure 18 wiring process.

[0246] Figure 18 The semiconductor light-emitting element of Figure 17 differs from the semiconductor light-emitting element of Figure 18 in that the area where the second passivation layer formed on the conductivity type electrode is removed. Figure 17 The semiconductor light-emitting element of

[0247] removes all of the second passivation layer formed on the conductivity type electrode, while Figure 18 the semiconductor light-emitting element of

[0248] removes a part of the second passivation layer formed on the conductivity type electrode.

[0249] Figure 19 Specifically represents Figure 16 a flowchart of another wiring process method performed on the semiconductor light-emitting element of

[0250] The another wiring process refers to the case where an etching process is first performed, rather than first forming an insulating layer on the semiconductor light-emitting element assembled on the second substrate.

[0251] As Figure 19 shown, first, a second passivation layer formed on a semiconductor light-emitting element assembled on a second substrate is removed (S1151). At this time, since the second passivation layer is exposed to the entire outside, it is entirely removed. After that, an insulating layer is formed on the side and upper portions of the semiconductor light-emitting element from which the second passivation layer has been removed (S1152), and then a planarization process is performed (S1153). In addition, a part of the planarized insulating layer is selectively removed to expose a part of the region of the conductive-type electrode of the semiconductor light-emitting element (S1154). Finally, an electrode is formed by depositing a conductive material such as metal on the exposed region (S1155).

[0252] On the other hand, from the overall spirit of this specification, deleting and changing a part of the steps of the flowchart shown Figure 19 at a level understandable to those skilled in the art also fall within the protection scope of the present invention.

[0253] Figure 20 is a cross-sectional view of a semiconductor light-emitting element in which a wiring process has been performed by Figure 19 the method.

[0254] As Figure 20 shown, the semiconductor light-emitting element 1702 after the wiring process includes a first conductive-type semiconductor layer 1011, an active layer 1012, a second conductive-type semiconductor layer 1013, a first conductive-type electrode 1015, a second conductive-type electrode 1014, and a first passivation layer 1021, and is located on a second substrate 1041.

[0255] In addition, there are no first passivation layer 1021 and second passivation layer 1022 on the upper portions of the first conductive-type electrode 1015 and the second conductive-type electrode 1014 of the semiconductor light-emitting element 1702.

[0256] In addition, a first electrode 1052 and a second electrode 1053 are located on a part of the upper portions of the first conductive-type electrode 1015 and the second conductive-type electrode 1014 of the semiconductor light-emitting element 1701, and an insulating layer 1051 is located on the upper portion and the side of the element so that the electrodes are not electrically connected to other regions of the semiconductor light-emitting element.

[0257] For example, Figure 20The semiconductor light-emitting element 1702 shown may be a semiconductor light-emitting element assembled by a self-assembly process. In the case of a semiconductor light-emitting element for self-assembly, in order to protect the element in a fluid, a passivation layer must also be formed on the upper part of the element at the time of assembly. However, after the self-assembly, the semiconductor light-emitting element assembled in the substrate performs an etching process to expose the conductive-type electrode on the upper part of the element for electrical connection. If, during this process, the semiconductor light-emitting element is self-assembled with a large alignment error, the accurate position of the conductive-type electrode cannot be accurately etched in the etching process, resulting in a short-circuit defect later. For example, if the semiconductor light-emitting element is protected by a single passivation layer, in the etching process for forming the second electrode, not only the passivation layer formed on the upper part of the second conductive-type electrode is removed, but also the passivation layer formed on the upper part of the first conductive-type semiconductor layer is removed, which may cause a short circuit between the first conductive-type semiconductor layer and the second conductive-type semiconductor layer when forming the electrode later. In addition, even if there are multiple passivation layers, if the conductive-type electrode region and other regions in the element are the same multiple passivation layer, similar to the element with a single passivation layer, misaligned etching can cause a short-circuit defect.

[0258] Therefore, when assembling a semiconductor light-emitting element, even if there is an alignment error, in order to stably form an electrode, the structure of the multiple passivation layers is particularly important so that only the electrical connection region of the element is selectively exposed. That is, a structure in which only the electrical connection region of the element is relatively easy to etch under the same conditions is required.

[0259] As Figure 20 shown, the semiconductor light-emitting element structure of the present invention can easily expose the conductive-type electrode of the semiconductor light-emitting element and stably form an electrode only by performing an etching process without an additional light process after assembly.

[0260] More specifically, in the case of performing a wet etching process after assembling the semiconductor light-emitting element 1702, if the first etching ratio of the first passivation layer 1021 of the semiconductor light-emitting element 1702 is less than the second etching ratio of the second passivation layer, the second passivation layer is etched, and even after passing a predetermined time in a wet etching state exposed to a chemical solution, the first passivation layer 1702 remains due to the etching ratio difference. Therefore, in the semiconductor light-emitting element 1702, the remaining regions except for the upper parts of the first conductive-type electrode 1015 and the second conductive-type electrode 1014 are completely protected by the second substrate 1041 and the first passivation layer 1021, so that stable wiring electrodes can be formed.

[0261] Although it is over Figure 20The structure of the semiconductor light-emitting element 1702 of the wiring process shown is similar to that of a general semiconductor light-emitting element, but this is the shape of the final product. For those skilled in the art, when considering the structure of the semiconductor light-emitting element and the wiring process when assembled on the second substrate 1041, the effects of the present invention can be easily judged.

[0262] Figure 21 FIG. is a diagram showing various electrode shapes that can be formed by a wiring process.

[0263] As described above, the semiconductor light-emitting element that performs the wiring process is formed with a first passivation layer and a second passivation layer, and the first etching ratio of the first passivation layer is smaller than the second etching ratio of the second passivation layer.

[0264] Figure 21 (a) is a top view of the structure of the semiconductor light-emitting element 1703 in which the second electrode 2153 is formed in a circular strip shape as viewed from above.

[0265] The semiconductor light-emitting element 1703 may have a circular horizontal semiconductor light-emitting structure, and the first conductive type electrode 1015 and the first electrode 2152 are located in the central region, and the second passivation layer 1022, the second conductive type electrode 1014, and the second electrode 2153 are arranged in a direction away from the central region.

[0266] Although the first conductive type electrode 1015 and the second conductive type electrode 1014 are illustrated in (a) in order to visually show the formation position of the second electrode 2153, in the actual structure, a first passivation layer and a second passivation layer 1022 are formed on the upper portions of the first conductive type electrode 1015 and the second conductive type electrode 1014. Figure 21 (a), a first passivation layer and a second passivation layer 1022 are formed on the upper portions of the first conductive type electrode 1015 and the second conductive type electrode 1014.

[0267] In the case of the semiconductor light-emitting element 1703, since the space for forming an electrode on the upper portion of the second conductive type electrode 1014 is wide, as shown in Figure 20 (a), a circular strip-shaped second electrode 2153 can be formed on the upper portion of the second conductive type electrode 1014.

[0268] Figure 21 (b) is a top view of the structure of the semiconductor light-emitting element 1704 in which the second electrode 2154 is formed in a plurality of circular shapes on the upper portion of the second conductive type electrode 1014 as viewed from above.

[0269] Figure 21 (c) is a top view of the structure of the semiconductor light-emitting element 1704 in which the second electrode 2155 is formed in a plurality of fan-shaped strips on the upper portion of the second conductive type electrode 1014 as viewed from above.

[0270] In the case of a semiconductor light-emitting element having a structure with multiple passivation layers having different etching ratios, since a part of the passivation layer with a high etching ratio exposed to the outside is easily removed, as Figure 21 shown, various electrodes can be formed. However, the form of the above electrodes is only an example, and the present invention is not limited thereto.

[0271] Figure 22 is a diagram showing a case where wiring electrodes are formed at respective positions for a semiconductor light-emitting element for performing Figure 17 a wiring process.

[0272] As Figure 22 (a) shows, Figure 16 a semiconductor light-emitting element 1700 is located on an insulating layer 1051.

[0273] The semiconductor light-emitting element 1700 includes a first conductive type electrode 1015, a second passivation layer 1022, and a second conductive type electrode 1014.

[0274] Although, Figure 22 (a) illustrates the first conductive type electrode 1015 and the second conductive type electrode 1014 for visually showing the effect of the present invention, in an actual structure, a first passivation layer and a second passivation layer 1022 are formed on the first conductive type electrode 1015 and the second conductive type electrode 1014.

[0275] In addition, a four-corner structure defining the outer contour of the insulating layer 1051 can be determined as an assembly groove for assembling the semiconductor light-emitting element 1700. Therefore, Figure 22 (a) of the semiconductor light-emitting element 1700 is a top view showing the shape assembled to the normal position in the assembly groove.

[0276] On the other hand, when manufacturing a display device, since the etching of a plurality of assembled semiconductor light-emitting elements and the wiring process of forming electrodes are performed together, the wiring process is performed assuming that the semiconductor light-emitting element is assembled to the normal position in the assembly groove.

[0277] Therefore, as Figure 22 (a) shows, if the semiconductor light-emitting element 1700 is assembled to the normal position, then afterwards, a first electrode 1052 and a second electrode 1053 will also accurately be located on the first conductive type semiconductor layer 1015 and the second conductive type semiconductor layer 1014.

[0278] On the contrary, as Figure 22As shown in (b), in the case of the semiconductor light-emitting element 1700 assembled at the upper left end of the assembly groove, when forming the wiring electrodes, the first electrode 1052 and the second electrode 1053 can be formed at the boundary surface between the first conductive-type semiconductor layer 1015 and the second conductive-type semiconductor layer 1014.

[0279] In the case of a semiconductor light-emitting element that is not a multi-passivation layer structure, the first conductive-type electrode 1015 and the second conductive-type electrode 1015 are short-circuited due to the first electrode 1052 formed at the boundary surface as described above, thus causing defects.

[0280] However, the semiconductor light-emitting element 1700 has a multi-passivation layer structure in which a first passivation layer and a second passivation layer 1022 are formed on the upper portions of the first conductive-type electrode 1015 and the second conductive-type electrode 1014. Therefore, even if the Figure 22 second passivation layer 1022 in (b) is removed, the first passivation layer remains, so it is difficult for the first conductive-type electrode 1015 and the second conductive-type electrode 1015 to be short-circuited.

[0281] In addition, as Figure 22 shown in (c), in the case of the semiconductor light-emitting element 1700 assembled at the lower right end of the assembly groove, when forming the wiring electrodes, the first electrode 1052 and the second electrode 1053 can be formed at the boundary surface between the first conductive-type semiconductor layer 1015 and the second conductive-type semiconductor layer 1014.

[0282] The electrodes 1052 and 1053 formed at the boundary surface cause short-circuit defects in a normal semiconductor element structure.

[0283] However, as described in Figure 22 (b), the semiconductor light-emitting element 1700 has a multi-passivation layer structure in which a first passivation layer and a second passivation layer 1022 are formed on the upper portions of the first conductive-type electrode 1015 and the second conductive-type electrode 1014. Therefore, even if the Figure 22 second passivation layer 1022 in (c) is removed, the first passivation layer remains, so it is difficult for the first conductive-type electrode 1015 and the second conductive-type electrode 1015 to be short-circuited.

[0284] As described above, the present invention has the advantage that even if the semiconductor light-emitting element is slightly assembled in the wrong position, it is possible to prevent short-circuit defects from occurring in the subsequent wiring process, which is a very important effect in terms of the panel yield.

[0285] The above is only an exemplary description of the technical idea of the present invention. For those of ordinary skill in the art, various modifications and variations can be made without departing from the technical idea of the present invention.

[0286] Therefore, the embodiments disclosed in the present invention are not used to limit the technical idea of the present invention, but for illustration purposes. The technical idea of the present invention is not limited to such embodiments.

[0287] The protection scope of the present invention shall be interpreted by the claims, and it should be interpreted that all technical ideas within the same scope are within the protection scope of the present invention.

Claims

1. A method of manufacturing a display device that uses a semiconductor light-emitting element, wherein, Comprising: The step of forming a semiconductor light-emitting element on a first substrate; The step of transferring the semiconductor light-emitting element onto a second substrate; The step of coating an insulating layer on the semiconductor light-emitting element transferred onto the second substrate; And The step of forming wiring electrodes electrically connected to the semiconductor light-emitting element; The step of forming the semiconductor light-emitting element includes: The step of forming a semiconductor light-emitting structure including a first conductivity type semiconductor layer, an active layer, a second conductivity type semiconductor layer, a first conductivity type electrode, and a second conductivity type electrode on the first substrate; The step of forming a first passivation layer on the semiconductor light-emitting structure; The step of selectively removing the first passivation layer formed on the upper portions of the first conductivity type electrode and the second conductivity type electrode of the semiconductor light-emitting structure; The step of forming a second passivation layer on the semiconductor light-emitting structure.

2. The manufacturing method of the display device according to claim 1, wherein, A step of removing the second passivation layer is included between the step of transferring onto the second substrate and the step of coating the insulating layer.

3. The manufacturing method of the display device according to claim 2, characterized in that, The step of removing the second passivation layer is performed by a wet etching process.

4. The manufacturing method of the display device according to claim 1, wherein, The step of coating the insulating layer includes: The step of planarizing the upper portion of the insulating layer.

5. The manufacturing method of the display device according to claim 1, wherein, The step of forming the wiring electrodes includes: The step of forming a first electrode electrically connected to the first conductivity type electrode of the semiconductor light-emitting element and a second electrode electrically connected to the second conductivity type electrode.

6. The manufacturing method of the display device according to claim 5, wherein, The step of forming the first electrode and the second electrode includes: The step of removing the second passivation layer formed on the upper portions of the first conductivity type electrode and the second conductivity type electrode.

7. The manufacturing method of the display device according to claim 5, wherein, The step of forming the first electrode and the second electrode includes: The step of selectively removing the second passivation layer in the overlapping regions between the first electrode and the first conductivity type electrode, between the second electrode and the second conductivity type electrode.

8. The manufacturing method of the display device according to claim 7, characterized in that, The step of selectively removing the second passivation layer is performed by a dry etching process.

9. A display device, which transfers a plurality of semiconductor light-emitting elements onto a substrate to form the display device, is characterized in that At least one of a plurality of the semiconductor light-emitting elements includes: A first conductivity type semiconductor layer; A second conductivity type semiconductor layer, located on the first conductivity type semiconductor layer; An active layer, disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer; A second conductivity type electrode, located on the second conductivity type semiconductor layer; A first conductivity type electrode, located in a region of the first conductivity type semiconductor layer exposed due to partial etching of the second conductivity type semiconductor layer and the active layer; and A first passivation layer and a second passivation layer, the first passivation layer and the second passivation layer are sequentially configured to surround the sides of the first-conductivity-type semiconductor layer and the second-conductivity-type semiconductor layer; The second passivation layer is located in the region above the first-conductivity-type electrode except for the portion in contact with the first electrode, The second passivation layer is located in the region above the second-conductivity-type electrode except for the portion in contact with the second electrode.

10. The display device according to claim 9, wherein, The first passivation layer and the second passivation layer are sequentially configured in the region above the first-conductivity-type semiconductor layer except for the portion in contact with the first-conductivity-type electrode, The first passivation layer and the second passivation layer are sequentially configured in the region above the second-conductivity-type semiconductor layer except for the portion in contact with the second-conductivity-type electrode.

11. The display device according to claim 9, wherein, The second passivation layer is located in the region above the first-conductivity-type semiconductor layer except for the portion in contact with the first-conductivity-type electrode, The second passivation layer is located in the region above the second-conductivity-type semiconductor layer except for the portion in contact with the second-conductivity-type electrode.

12. The display device according to claim 9, wherein, The first etching ratio of the first passivation layer is less than the second etching ratio of the second passivation layer.

13. The display device according to claim 9, wherein, The first passivation layer includes the same material as the second passivation layer.

14. The display device according to claim 13, wherein, The thickness of the second passivation layer is thinner than the thickness of the first passivation layer.

15. The display device according to claim 9, wherein, A magnetic layer is included below the first-conductivity-type electrode or the second-conductivity-type electrode.

16. The display device according to claim 9, wherein, The semiconductor light-emitting element is an LED (Micro-LED) having a size in the micron unit.

17. A display device, characterized in that, Comprising: A substrate; A plurality of semiconductor light-emitting elements transferred onto the substrate, at least one of the plurality of semiconductor light-emitting elements includes a first-conductivity-type semiconductor layer, a second-conductivity-type semiconductor layer, a first-conductivity-type electrode connected to the first-conductivity-type semiconductor layer, and a second-conductivity-type electrode connected to the second-conductivity-type semiconductor layer; A first electrode connected to the first-conductivity-type electrode of the semiconductor light-emitting element; And A second electrode connected to the second-conductivity-type electrode of the semiconductor light-emitting element; The semiconductor light-emitting element includes: A first passivation layer located on the sides of the first-conductivity-type semiconductor layer and the second-conductivity-type semiconductor layer; and A second passivation layer located on the first passivation layer; The thickness of the second passivation layer is thinner than the thickness of the first passivation layer.

18. The display device according to claim 17, wherein, The second passivation layer is further located on the first-conductivity-type electrode and the second-conductivity-type electrode.

19. The display device according to claim 18, wherein, The first electrode and the second electrode respectively penetrate through the second passivation layer and are connected to the first conductivity type electrode and the second conductivity type electrode.

20. The display device according to claim 17, wherein a first etching ratio of the first passivation layer is less than a second etching ratio of the second passivation layer.

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