Semiconductor light-emitting device for display pixel, and display apparatus comprising same

Abstract

A semiconductor light-emitting device for a display pixel according to an embodiment may comprise: a light-emitting structure having a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer; a first electrode disposed under the light-emitting structure; a second electrode disposed on the light-emitting structure; and a first passivation layer disposed on the second electrode so as to extend to a side surface of the first conductive semiconductor layer.

Description

Semiconductor light-emitting element for display pixels and display device including the same

[0001] The present invention relates to a semiconductor light-emitting element for a display pixel and a display device including the same.

[0002] Large-area displays include liquid crystal displays (LCDs), OLED displays, and micro-LED displays.

[0003] A micro-LED display is a display that uses micro-LEDs, which are semiconductor light-emitting elements with a diameter or cross-sectional area of ​​100㎛ or less, as display elements.

[0004] Micro-LED displays use semiconductor light-emitting diodes (micro-LEDs) as display elements, so they have superior performance in many characteristics, including contrast ratio, response speed, color reproducibility, viewing angle, brightness, resolution, lifespan, luminous efficiency, and brightness.

[0005] In particular, micro-LED displays have the advantage of being able to freely adjust the size and resolution by separating and combining the screen in a modular manner, and of being able to implement a flexible display.

[0006]

[0007] However, large-scale micro-LED displays require millions or more micro-LEDs, which poses a technical challenge in quickly and accurately transferring micro-LEDs to the display panel.

[0008] Recently developed transfer technologies include the pick and place process, the laser lift-off method, and the self-assembly method.

[0009] Among these, the self-assembly method is advantageous for implementing large-screen display devices, as it is a method in which semiconductor light-emitting elements find their own assembly positions within a fluid.

[0010] Recently, U.S. Patent No. 9,825,202 presented a micro-LED structure suitable for self-assembly, but research on the technology for manufacturing displays through self-assembly of micro-LEDs is still insufficient.

[0011] In particular, in the case of rapidly transferring millions or more semiconductor light-emitting elements to a large display in the prior art, there is a technical problem that although the transfer speed can be improved, the transfer error rate can increase, resulting in a lower transfer yield.

[0012] Meanwhile, a self-assembly transfer process using dielectrophoresis (DEP) is being attempted in related technologies, but there is a problem of low self-assembly rate due to non-uniformity of DEP force.

[0013] Meanwhile, when wiring is connected laterally to a chip in a display device, the contact area between the panel electrode and the chip is small, resulting in poor electrical performance and problems with poor contact.

[0014] One of the technical challenges of the embodiment is to increase the electrical contact area between the side wiring of the display panel and the semiconductor light-emitting element.

[0015] Additionally, one of the technical challenges of the embodiment is to prevent incorrect assembly during self-assembly.

[0016] One of the technical challenges of the embodiment is to prevent oxidation of the semiconductor light-emitting element in the fluid during self-assembly.

[0017] One of the technical challenges of the embodiment is to improve the luminous efficiency of a semiconductor light-emitting device.

[0018] The technical tasks of the embodiment are not limited to those described in this article, but include those that can be understood through the description of the invention.

[0019] A semiconductor light-emitting device according to an embodiment comprises a light-emitting structure comprising a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer; a first electrode disposed under the light-emitting structure;

[0020] A second electrode disposed on the light-emitting structure may be included, and a first passivation layer may be disposed on the second electrode and extending to the side of the first conductive semiconductor layer.

[0021] Additionally, in the embodiment, the side surface of the first conductive semiconductor layer may include a first region that is in contact with the passivation layer and a second region that is not in contact with the passivation layer.

[0022] Additionally, in an embodiment, the passivation layer may further include a second passivation layer disposed under the first electrode.

[0023] Additionally, in the embodiment, the passivation layer further includes a third passivation layer disposed in the second region, and the thickness of the third passivation layer may be thinner than the thickness of the first passivation layer.

[0024]

[0025] In addition, a display device including a semiconductor light emitting element according to another embodiment comprises: a substrate;

[0026] A semiconductor light-emitting device disposed on the substrate; and a first panel electrode and a second panel electrode connected to the semiconductor light-emitting device, wherein the semiconductor light-emitting device includes a first electrode, a first conductive semiconductor layer disposed on the first electrode, an active layer disposed on the first conductive semiconductor layer, a second conductive semiconductor layer disposed on the active layer, and a second electrode disposed on the second conductive semiconductor layer, and further includes a passivation layer disposed on the second electrode to extend laterally from the first conductive semiconductor layer, wherein the first panel electrode can be connected to the first electrode and the first conductive semiconductor layer of the semiconductor light-emitting device.

[0027] Additionally, in the embodiment, the first conductive semiconductor layer includes a first region in contact with the passivation layer and a second region not in contact, and the second region can be connected to the first panel electrode.

[0028] In addition, the embodiment further includes a second passivation layer disposed under the first electrode.

[0029] Additionally, in an embodiment, the substrate may further include a plurality of assembly wires spaced apart from each other, and may further include an insulating layer between the plurality of assembly wires and the semiconductor light-emitting element.

[0030] Additionally, in the embodiment, an adhesive layer may be further included between the substrate and the semiconductor light-emitting element.

[0031] Additionally, in the embodiment, the adhesive layer includes a first adhesive layer that vertically overlaps the semiconductor light-emitting element and a second adhesive layer that does not vertically overlap, and the thickness of the second adhesive layer may be thinner than the thickness of the first adhesive layer.

[0032] A semiconductor light-emitting device according to an embodiment and a display device including the same have a technical effect of increasing an electrical contact area with a panel electrode in a side wiring process.

[0033] For example, the embodiment may form the passivation layer to expose a portion of the side surface of the first conductive semiconductor layer, thereby increasing the electrical contact area by allowing the side wiring to be connected to the first conductive semiconductor layer.

[0034] In addition, the embodiment has a technical effect that can prevent poor contact of side wiring.

[0035] For example, the embodiment can prevent the problem of poor contact during the wiring process by having a small contact area of ​​the side wiring.

[0036] In addition, the embodiment has a technical effect of preventing incorrect assembly during self-assembly of a semiconductor light-emitting device.

[0037] For example, the embodiment can prevent incorrect assembly by allowing the passivation layer to be easily removed during assembly to the side of the semiconductor light-emitting device through the shape of the passivation layer.

[0038] In addition, the embodiment has a technical effect of preventing oxidation of an electrode of a semiconductor light-emitting device.

[0039] For example, the embodiment can form a passivation layer under the electrode of a semiconductor light-emitting device to prevent oxidation of the electrode in fluid assembly.

[0040] The technical effects of the embodiments are not limited to those described in this article, but include those that can be understood through the description of the invention.

[0041] Figure 1 is an exemplary diagram of a living room of a house in which a display device according to an embodiment is placed.

[0042] Figure 2 is an enlarged view of the first panel area in the display device of Figure 1.

[0043] Fig. 3 is a cross-sectional view along line B1-B2 of area A2 of Fig. 2.

[0044] Fig. 4 is an exemplary diagram showing a light-emitting element according to an embodiment being assembled on a substrate by a self-assembly method.

[0045] Figure 5 is a conceptual diagram of a display device including a semiconductor light-emitting element being studied internally.

[0046] Fig. 6 is a cross-sectional view of a semiconductor light-emitting device according to the first embodiment.

[0047] Fig. 7 is a cross-sectional view of a semiconductor light-emitting device according to the second embodiment.

[0048] Fig. 8 is a cross-sectional view of a semiconductor light-emitting device according to the third embodiment.

[0049] Fig. 9 is a cross-sectional view of a semiconductor light-emitting device according to the fourth embodiment.

[0050] Fig. 10 is a cross-sectional view of a display device including a semiconductor light-emitting element according to the fifth embodiment.

[0051] Fig. 11 is a cross-sectional view of a display device including a semiconductor light-emitting element according to the sixth embodiment.

[0052] Fig. 12 is a cross-sectional view of a display device including a semiconductor light-emitting element according to the seventh embodiment.

[0053] Figures 13a to 13f are manufacturing process diagrams of a semiconductor light-emitting device according to an embodiment.

[0054] Hereinafter, embodiments disclosed in the present specification will be described in detail with reference to the attached drawings. The suffixes "module" and "part" used in the following description for components are given or used interchangeably for the sake of ease of writing the specification, and do not in themselves have distinct meanings or roles. In addition, the attached drawings are intended to facilitate easy understanding of the embodiments disclosed in the present specification, and the technical ideas disclosed in the present specification are not limited by the attached drawings. In addition, when an element such as a layer, region, or substrate is referred to as existing "on" another element, this includes that it may be directly on the other element, or that other intermediate elements may exist therebetween.

[0055] The display devices described in this specification may include digital TVs, mobile phones, smart phones, laptop computers, digital broadcasting terminals, personal digital assistants (PDAs), portable multimedia players (PMPs), navigation devices, slate PCs, tablet PCs, Ultra-Books, desktop computers, and the like. However, the configuration according to the embodiments described in this specification may also be applied to devices capable of displaying, even if they are new product types developed in the future.

[0056]

[0057] A light-emitting element and a display device including the same according to the following embodiment are described.

[0058] FIG. 1 illustrates a living room of a house in which a display device (100) according to an embodiment is placed.

[0059] The display device (100) of the embodiment can display the status of various electronic products such as a washing machine (101), a robot vacuum cleaner (102), and an air purifier (103), and can communicate with each electronic product based on IOT and control each electronic product based on user setting data.

[0060] A display device (100) according to an embodiment may include a flexible display manufactured on a thin and flexible substrate. The flexible display can be bent or rolled like paper while maintaining the characteristics of a conventional flat panel display.

[0061] In a flexible display, visual information can be realized by independently controlling the emission of unit pixels arranged in a matrix form. A unit pixel refers to the smallest unit for realizing a single color. The unit pixels of a flexible display can be realized by light-emitting elements. In an embodiment, the light-emitting elements may be micro-LEDs or nano-LEDs, but are not limited thereto.

[0062]

[0063] Figure 2 is an enlarged view of the first panel area (A1) in the display device of Figure 1.

[0064] According to FIG. 2, the display device (100) of the embodiment can be manufactured by mechanically and electrically connecting a plurality of panel areas, such as the first panel area (A1), through tiling.

[0065] The first panel area (A1) may include a plurality of light-emitting elements (150) arranged for each unit pixel (PX in FIG. 2).

[0066] For example, a unit pixel (PX) may include a first sub-pixel (PX1), a second sub-pixel (PX2), and a third sub-pixel (PX3). For example, a plurality of red light-emitting elements (150R) may be arranged in the first sub-pixel (PX1), a plurality of green light-emitting elements (150G) may be arranged in the second sub-pixel (PX2), and a plurality of blue light-emitting elements (150B) may be arranged in the third sub-pixel (PX3). The unit pixel (PX) may further include a fourth sub-pixel in which no light-emitting element is arranged, but this is not limited thereto. Meanwhile, the light-emitting element (150) may be a semiconductor light-emitting element.

[0067]

[0068] Next, Fig. 3 is a cross-sectional view along line B1-B2 of area A2 of Fig. 2.

[0069] Referring to FIG. 3, the display device (100) of the embodiment may include a substrate (200), assembly wiring (201, 202), a first insulating layer (211a), a second insulating layer (211b), a third insulating layer (206), and a plurality of light-emitting elements (150).

[0070] The assembly wiring may include a first assembly wiring (201) and a second assembly wiring (202) that are spaced apart from each other. The first assembly wiring (201) and the second assembly wiring (202) may be provided to generate a dielectrophoretic force for assembling the light emitting element (150). In addition, the first assembly wiring (201) and the second assembly wiring (202) may be electrically connected to electrodes of the light emitting element to function as electrodes of the display panel.

[0071] The assembly wiring (201, 202) may be formed of a light-transmitting electrode (ITO) or may include a metal material with excellent electrical conductivity. For example, the assembly wiring (201, 202) may be formed of at least one of titanium (Ti), chromium (Cr), nickel (Ni), aluminum (Al), platinum (Pt), gold (Au), tungsten (W), molybdenum (Mo), or an alloy thereof.

[0072] A first insulating layer (211a) may be disposed between the first assembly wiring (201) and the second assembly wiring (202), and a second insulating layer (211b) may be disposed on the first assembly wiring (201) and the second assembly wiring (202). The first insulating layer (211a) and the second insulating layer (211b) may be an oxide film, a nitride film, or the like, but are not limited thereto.

[0073]

[0074] The light-emitting element (150) may include a red light-emitting element (150), a green light-emitting element (150G), and a blue light-emitting element (150B0) to form a unit pixel (sub-pixel), but is not limited thereto, and may also include a red phosphor and a green phosphor to implement red and green, respectively.

[0075] The substrate (200) may be formed of glass or polyimide. In addition, the substrate (200) may include a flexible material such as polyethylene naphthalate (PEN) or polyethylene terephthalate (PET). In addition, the substrate (200) may be a transparent material, but is not limited thereto.

[0076] The third insulating layer (206) may include an insulating and flexible material such as polyimide, PEN, PET, etc., and may be formed integrally with the substrate (200) to form a single substrate.

[0077] The third insulating layer (206) may be a conductive adhesive layer having adhesive properties and conductivity, and the conductive adhesive layer may be flexible to enable a flexible function of the display device. For example, the third insulating layer (206) may be a conductive adhesive layer such as an anisotropic conductive film (ACF) or an anisotropic conductive medium, a solution containing conductive particles, etc. The conductive adhesive layer may be a layer that is electrically conductive in a direction vertical to the thickness, but electrically insulating in a direction horizontal to the thickness.

[0078] The third insulating layer (206) may include an assembly hole (203) into which a light-emitting element (150) is inserted. Therefore, during self-assembly, the light-emitting element (150) can be easily inserted into the assembly hole (203) of the third insulating layer (206). The assembly hole (203) may be referred to as an insertion hole, a fixing hole, an alignment hole, or the like.

[0079] The gap between the assembly wiring (201, 202) is formed to be smaller than the width of the light emitting element (150) and the width of the assembly hole (203), so that the assembly position of the light emitting element (150) can be fixed more precisely using an electric field.

[0080] A third insulating layer (206) is formed on the assembly wiring (201, 202) to protect the assembly wiring (201, 202) from the fluid (1200) and prevent leakage of current flowing in the assembly wiring (201, 202). The third insulating layer (206) may be formed as a single layer or multiple layers of an inorganic insulator such as silica or alumina or an organic insulator.

[0081] Additionally, the third insulating layer (206) may include an insulating and flexible material such as polyimide, PEN, PET, etc., and may be formed integrally with the substrate (200) to form a single substrate.

[0082] The third insulating layer (206) may be an adhesive insulating layer or a conductive adhesive layer having conductivity. The third insulating layer (206) may be flexible, thereby enabling a flexible function of the display device.

[0083] The third insulating layer (206) has a partition wall, and an assembly hole (203) can be formed by this partition wall. For example, when forming the substrate (200), a part of the third insulating layer (206) is removed, so that each of the light emitting elements (150) can be assembled into the assembly hole (203) of the third insulating layer (206).

[0084] An assembly hole (203) is formed in the substrate (200) to which light-emitting elements (150) are coupled, and the surface where the assembly hole (203) is formed can come into contact with a fluid (1200). The assembly hole (203) can guide the exact assembly position of the light-emitting elements (150).

[0085] Meanwhile, the assembly hole (203) may have a shape and size corresponding to the shape of the light-emitting element (150) to be assembled at the corresponding position. Accordingly, it is possible to prevent another light-emitting element from being assembled in the assembly hole (203) or multiple light-emitting elements from being assembled.

[0086]

[0087] FIG. 4 is a drawing showing an example in which a light-emitting element according to an embodiment is assembled on a substrate by a self-assembly method, and the self-assembly method of the light-emitting element is explained with reference to the drawings.

[0088] The substrate (200) may be a panel substrate of a display device. In the following description, the substrate (200) is described as a panel substrate of a display device, but the embodiment is not limited thereto.

[0089] Referring to FIG. 4, a plurality of light-emitting elements (150) may be placed in a chamber (1300) filled with a fluid (1200). The fluid (1200) may be, but is not limited to, water such as ultrapure water. The chamber may be referred to as a tank, a container, a vessel, or the like.

[0090] After this, the substrate (200) can be placed on the chamber (1300). Depending on the embodiment, the substrate (200) can also be introduced into the chamber (1300).

[0091] As shown in FIG. 3, a pair of assembly wirings (201, 202) corresponding to each light emitting element (150) to be assembled can be arranged on the substrate (200).

[0092] Referring to FIG. 4, after the substrate (200) is placed, an assembly device (1100) including a magnetic body can move along the substrate (200). For example, a magnet or an electromagnet can be used as the magnetic body. The assembly device (1100) can move in contact with the substrate (200) to maximize the area affected by the magnetic field within the fluid (1200). Depending on the embodiment, the assembly device (1100) may include a plurality of magnetic bodies or may include magnetic bodies of a size corresponding to that of the substrate (200). In this case, the movement distance of the assembly device (1100) may be limited within a predetermined range.

[0093] By the magnetic field generated by the assembly device (1100), the light emitting element (150) within the chamber (1300) can move toward the assembly device (1100).

[0094] The light emitting element (150) may move toward the assembly device (1100) and enter the assembly hole (203) by the dielectric electrophoretic force (DEP force) to come into contact with the substrate (200).

[0095] Specifically, the assembly wiring (201, 202) forms an electric field by an externally supplied power source, and a dielectric force can be formed between the assembly wiring (201, 202) by this electric field. The light-emitting element (150) can be fixed to the assembly hole (203) on the substrate (200) by this dielectric force.

[0096] The light emitting element (150) in contact with the substrate (200) can be prevented from being detached by the movement of the assembly device (1100) due to the electric field applied by the assembly wiring (201, 202) formed on the substrate (200). According to an embodiment, the time required for each of the light emitting elements (150) to be assembled on the substrate (200) can be drastically shortened by the self-assembly method using the electromagnetic field described above, so that a large-area, high-pixel display can be implemented more quickly and economically.

[0097] At this time, a predetermined solder layer (not shown) is formed between the light emitting element (150) assembled on the assembly hole (203) of the substrate (200) and the assembly electrode, thereby improving the bonding strength of the light emitting element (150).

[0098] Next, a molding layer (not shown) may be formed in the assembly hole (203) of the substrate (200). The molding layer may be a light-transmitting resin or a resin containing a reflective material or a scattering material.

[0099]

[0100] FIG. 5 is a cross-sectional view of a display device including a semiconductor light-emitting element studied in internal technology. Referring to FIG. 5, a semiconductor light-emitting element (50) is disposed on a substrate (10), and the semiconductor light-emitting element (50) may be electrically connected to a first panel electrode (61) and a second panel electrode (62). Meanwhile, the semiconductor light-emitting element (50) may include a passivation layer (40) and a first electrode (31). The passivation layer (40) may be disposed to cover the entire side surface of the light-emitting structure. Accordingly, the semiconductor light-emitting element may expose only the side surface of the first electrode (31). When a side wiring process is performed in the display device, the first panel electrode (61) may come into contact with the side surface area (R) of the first electrode (31). However, since the electrical connection between the first panel electrode (61) and the semiconductor light emitting element (50) is limited to the side region (R), the electrical connection area is small, which may result in a deterioration in electrical performance. In addition, the reduced contact area may cause a problem of poor contact during the panel electrode process. In addition, even if a connection is attempted by etching a portion of the passivation layer (40), it is difficult to control the degree of etching of the passivation layer (40), and thus, only the connection with the first electrode (31) may be relied on.

[0101]

[0102] Hereinafter, an embodiment for solving the above problem will be described.

[0103] Fig. 6 is a cross-sectional view of a semiconductor light-emitting device (150a) according to a first embodiment. The first embodiment may be a vertical semiconductor light-emitting device, but is not limited thereto. Referring to Fig. 6, the semiconductor light-emitting device (150a) may include a first electrode (131), a light-emitting structure (130) disposed on the first electrode (131), and a second electrode (135) disposed on the light-emitting structure (130). The light-emitting structure (130) may include a first conductive semiconductor layer (132), an active layer (133) disposed on the first conductive semiconductor layer (132), and a second conductive semiconductor layer (134) disposed on the active layer (133).

[0104] The first conductive semiconductor layer (132) may be an n-type semiconductor layer, and the second conductive semiconductor layer (134) may be a p-type semiconductor layer, but is not limited thereto. The first conductive semiconductor layer (132), the active layer (133), and the second conductive semiconductor layer (134) may be formed of a compound semiconductor material. For example, the compound semiconductor material may be a group III-V compound semiconductor material, a group II-VI compound material, etc. For example, the compound semiconductor may be a binary compound selected from the group consisting of GaP, GaAs, GaSb, AlP, AlAs, AlSb, InP, InAs, InSb, and mixtures thereof; a ternary compound selected from the group consisting of GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlInP, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, and mixtures thereof; and a group consisting of four-element compounds selected from the group consisting of AlGaInP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb and mixtures thereof.

[0105] For example, the first conductive semiconductor layer (132) may include a first conductive dopant, and the second conductive semiconductor layer (134) may include a second conductive dopant. For example, the first conductive dopant may be an n-type dopant such as silicon (Si), and the second conductive dopant may be a p-type dopant such as boron (B).

[0106] The active layer (133) is a region that generates light, and can generate light having a specific wavelength band depending on the material properties of the compound semiconductor. In addition, the active layer (133) may have a multiple quantum well or single quantum well structure, and the wavelength band may be determined by the energy band gap of the compound semiconductor included in the active layer (133). Therefore, the semiconductor light-emitting device of the embodiment can generate UV light, blue light, green light, and red light depending on the energy band gap of the compound semiconductor included in the active layer (133).

[0107] Meanwhile, the semiconductor light emitting element (150a) may include a passivation layer (140). The passivation layer (140) may be arranged to cover a portion of the light emitting structure (130). The passivation layer (140) covers the second electrode (135) and may be arranged on a side surface of the light emitting structure (130). The passivation layer (140) may be formed of an oxide film. For example, the passivation layer (140) may include any one of SiOx, SiNx, and Al2O3, but is not limited thereto.

[0108] At this time, the passivation layer (140) covers all of the side surfaces of the active layer (133) and the second conductive semiconductor layer (134), and may partially expose the side surface of the first conductive semiconductor layer (132). The bottom surface of the passivation layer (140) may be located below the active layer (133). The first conductive semiconductor layer (132) may include a first region that is in contact with the passivation layer (140) and a second region that is not in contact with it.

[0109] Accordingly, the embodiment has a technical effect in that the side surface of the first conductive semiconductor layer is exposed, so that during the side wiring process in the display panel, the panel electrode can contact not only the first electrode but also the side surface of the first conductive semiconductor layer, thereby securing a wide contact area. In addition, the light efficiency of the semiconductor light-emitting element can be improved.

[0110] Meanwhile, when self-assembling a semiconductor light-emitting device, if the semiconductor light-emitting device is assembled laterally in the assembly hole, there was a problem that the assembly rate was reduced because incorrectly assembled chips were not removed. Meanwhile, the embodiment has a special technical effect in that since the passivation layer is only partially formed on the side of the semiconductor light-emitting device (150a), even if it is assembled laterally in the assembly hole, the contact area with the panel is small and can be easily removed, thereby preventing incorrect assembly.

[0111]

[0112] Fig. 7 is a cross-sectional view of a semiconductor light-emitting device (150b) according to a second embodiment. The second embodiment may employ the technical features of the first embodiment. For example, the second embodiment has the technical effect of allowing the passivation layer (140) to partially expose the side surface of the first conductive semiconductor layer (132), thereby improving the electrical contact area with the side wiring, and preventing incorrect assembly that occurs when self-assembly is performed sideways.

[0113] Referring to FIG. 7, the passivation layer (140) of the second embodiment may include a first passivation layer (141) that is arranged to extend over a second electrode (135) to cover one side of the first semiconductor layer (132) and a second passivation layer (142) that is arranged under the first electrode (131). In addition, the first passivation layer (141) and the second passivation layer (142) may include the same material. In addition, the first passivation layer (141) and the second passivation layer (142) may include different materials.

[0114] The above second passivation layer (142) has a technical effect of preventing oxidation of the first electrode (131) and providing protection.

[0115]

[0116] Fig. 8 is a cross-sectional view of a semiconductor light-emitting device (150c) according to a third embodiment. The third embodiment may employ the technical features of the second embodiment. For example, the third embodiment has the technical effect of allowing the passivation layer (140) to partially expose the side surface of the first conductive semiconductor layer (132), thereby improving the electrical contact area with the side wiring, and preventing incorrect assembly that occurs when self-assembly is performed sideways.

[0117] Referring to FIG. 8, the passivation layer (140) of the semiconductor light-emitting device (150c) according to the third embodiment may include a first passivation layer (141) that is arranged to extend from one side of the first conductive semiconductor layer (132) on the first electrode (135), a second passivation layer (142) that is arranged below the first electrode (131), and a third passivation layer (143) that is arranged between the first passivation layer (141) and the second passivation layer (142).

[0118] The third passivation layer (143) may include the same material as the first passivation layer (141), but is not limited thereto.

[0119] The third passivation layer (143) may be arranged on the side surface of the first conductive semiconductor layer (132). The side surface of the first conductive semiconductor layer (132) may be in contact with the first passivation layer (141) and the third passivation layer (143). In addition, the thickness of the third passivation layer (143) may be formed thinner than the thickness of the first passivation layer (141). Accordingly, the passivation layer may prevent oxidation in a fluid during self-assembly of a semiconductor light-emitting device and may prevent clumping between chips. In addition, there is a technical effect of preventing incorrect assembly by forming a step due to a difference in thickness, so that the chip can be easily removed when assembled laterally.

[0120]

[0121] Fig. 9 is a cross-sectional view of a semiconductor light-emitting device (150d) according to a fourth embodiment. The fourth embodiment may be a semiconductor light-emitting device having a vertical structure. Meanwhile, the semiconductor light-emitting device (150d) of the fourth embodiment may include a step region in the first conductive semiconductor layer (132). The step region may be formed by mesa-etching a portion of the first conductive semiconductor layer (132).

[0122] In addition, the passivation layer (140) may be arranged up to the step region on the second electrode (135). Accordingly, a portion of the first conductive semiconductor layer (132) may be exposed. Therefore, the fourth embodiment has a technical effect in that the vertical semiconductor light-emitting device includes a step region in the first conductive semiconductor layer, and the step region can be utilized as a guide region when forming a passivation layer. In addition, the side surface of the first conductive semiconductor layer may be exposed, thereby increasing the contact area with the panel electrode.

[0123]

[0124] Fig. 10 is a cross-sectional view of a display device including a semiconductor light-emitting device according to a fifth embodiment. In the fifth embodiment, the semiconductor light-emitting device may be the semiconductor light-emitting device of the first to fourth embodiments. Referring to Fig. 10, the semiconductor light-emitting device may be assembled on an assembly substrate (111). The assembly substrate (111) may include an assembly electrode and a thin film transistor (TFT). The assembly substrate (111) is utilized as an assembly substrate, and may be utilized as a display panel substrate through a subsequent panel process.

[0125] The above semiconductor light-emitting device (150) may be a vertical semiconductor light-emitting device. The bottom surface of the passivation layer (140) is formed lower than the active layer, and the first conductive semiconductor layer (132) may be partially exposed by the passivation layer (140).

[0126] Meanwhile, an insulating layer (160) may be placed between the assembly substrate (111) and the semiconductor light-emitting element (150), and the insulating layer (160) may expose the TFT electrode (165). The insulating layer (160) may function as a buffer layer that protects the TFT of the assembly substrate.

[0127] Meanwhile, a first panel electrode (161) may be placed on the insulating layer (160) to be connected to the TFT electrode (165) and the semiconductor light-emitting element (150).

[0128] The above first panel electrode (161) can be electrically connected to the side of the first electrode (131) and the first conductive semiconductor layer (132) of the semiconductor light emitting element (150).

[0129] Additionally, a planarization layer (170) may be arranged to cover the semiconductor light-emitting element (150) and the first panel electrode (161). The upper surface of the planarization layer (170) may be positioned higher than the upper surface of the semiconductor light-emitting element (150), but is not limited thereto.

[0130] Accordingly, the fifth embodiment has a technical effect of increasing the electrical contact area by exposing the side surface of the first conductive semiconductor layer (132) by the passivation layer (140), so that the first panel electrode (161) is connected not only to the first electrode (131) but also to the side surface of the first conductive semiconductor layer (132). Accordingly, electrical performance is improved, and there is a technical effect of solving the problem of poor contact in the wiring process.

[0131]

[0132] Fig. 11 is a cross-sectional view of a display device including a semiconductor light-emitting device according to a sixth embodiment. The sixth embodiment may adopt the technical features of the fifth embodiment. For example, the first panel electrode (161) is connected not only to the first electrode (131) of the semiconductor light-emitting device (150) but also to the side surface of the first conductive semiconductor layer (132), which has the technical effect of improving the electrical contact area. Referring to Fig. 11, an adhesive layer (175) may be disposed on a substrate (110), and a semiconductor light-emitting device (150) may be disposed on the adhesive layer (175). The semiconductor light-emitting device (150) may be assembled on an assembly substrate (not shown) and then transferred and disposed on the substrate (110). The adhesive layer (175) may be formed to have the same horizontal width as the semiconductor light-emitting device. Accordingly, in the sixth embodiment, the first panel electrode (161) is in contact with the side surface of the adhesive layer (175) and is connected to the semiconductor light-emitting element (150), so there is a technical effect that the contact reliability of the first panel electrode (161) can be improved.

[0133]

[0134] Fig. 12 is a cross-sectional view of a display device including a semiconductor light-emitting element according to the seventh embodiment. Referring to Fig. 12, an insulating layer (160) may be disposed on the substrate (110), and an adhesive layer (175) may be disposed to cover the insulating layer (160). The horizontal width of the adhesive layer (175) may be larger than the horizontal width of the semiconductor light-emitting element (150). In addition, the first panel electrode (161) may be connected to the semiconductor light-emitting element (150) along the adhesive layer (175) at the TFT electrode (165). The upper surface of the adhesive layer (175) may include a region in contact with the semiconductor light-emitting element and a region in contact with the first panel electrode.

[0135] In addition, the adhesive layer (175) may include a first adhesive layer (175a) that vertically overlaps the semiconductor light emitting element (150) and a second region (175b) that does not vertically overlap. The thicknesses of the first adhesive layer (175a) and the second adhesive layer (175b) may be formed differently. The thickness of the second adhesive layer (175b) may be formed thinner than the thickness of the first adhesive layer (175a).

[0136] Accordingly, the seventh embodiment has a technical effect of improving the structural reliability of the first panel electrode and preventing poor contact between the first panel electrode and the semiconductor light-emitting element.

[0137]

[0138] Figures 13a to 13f are process diagrams for manufacturing a semiconductor light-emitting device of an embodiment. Referring to Figure 13a, a light-emitting structure (130) may be formed on a growth substrate (115). The light-emitting structure (130) may include a first conductive semiconductor layer (132), an active layer, and a second conductive semiconductor layer (134). A second electrode (135) may be formed on the light-emitting structure (130), and the second electrode (135) may be formed as a transparent electrode. For example, the second electrode (135) may include ITO, IZO, ZnO, or the like, but is not limited thereto. In addition, a passivation layer (140) may be formed to cover both the second electrode (135) and the light-emitting structure (130).

[0139]

[0140] Referring to FIG. 13b, a sacrificial layer (121) may be formed to cover the upper and side surfaces of the passivation layer (140). The sacrificial layer (121) may include Al, but is not limited thereto. In addition, the semiconductor light-emitting element (150) on the growth substrate (115) may be bonded to the temporary substrate (116) through the bonding PR (122) formed on the upper portion of the sacrificial layer (121).

[0141]

[0142] Referring to FIG. 13c, the growth substrate and the temporary substrate can be flipped over so that the temporary substrate (116) in FIG. 13b faces downward. Thereafter, the growth substrate that was in contact with the back surface of the semiconductor light-emitting device (150) can be removed. When removing the growth substrate, a method such as LLO (Laser lift-off) can be used. Thereafter, PR (124) can be coated on the temporary substrate (116) to surround the periphery of the semiconductor light-emitting device (150).

[0143]

[0144] Referring to FIG. 13d, the PR (124) can be etched at a height where the active layer of the semiconductor light-emitting device (150) is not exposed. In addition, the sacrificial layer (121) can be etched to correspond to the height at which the PR (124) is etched. In addition, the exposed passivation layer (140) can be etched. Accordingly, the side surface of the active layer in the semiconductor light-emitting device (150) is covered by the passivation layer (140), and a portion of the side surface of the first conductive semiconductor light-emitting device can be exposed.

[0145]

[0146] Next, referring to FIG. 13e, a first electrode (131) may be formed on the back of the light-emitting structure (130). In addition, a second passivation layer (142) may be formed on the back of the light-emitting structure (130). The second passivation layer (142) may be formed of a different material from the first passivation layer (141), but is not limited thereto. A third passivation layer (143) may be formed on a side surface of the first conductive semiconductor layer (132). The third passivation layer (143) may be formed to a thickness thinner than the first passivation layer (141). In addition, the third passivation layer (143) may be formed of a different material from the first passivation layer (141), but is not limited thereto. Accordingly, a passivation layer (140) can be formed to surround the light-emitting structure (130). Depending on the deposition process, the second passivation layer (142) and the third passivation layer (143) can be selectively formed. Thereafter, a process of removing the PR and etching the sacrificial layer can be performed.

[0147]

[0148] Referring to FIG. 13F, a temporary substrate may be removed and a semiconductor light-emitting device may be formed. The semiconductor light-emitting device may include a passivation layer (140) surrounding a light-emitting structure (130). The passivation layer may further include a first passivation layer (141) disposed to extend from one side of a first conductive semiconductor layer (132) on a second electrode (135), a second passivation layer (142) disposed under the first electrode (131), and a third passivation layer (143) disposed between the first passivation layer (141) and the second passivation layer (142). The passivation layer (140) may prevent oxidation when assembling the semiconductor light-emitting device in a fluid and may prevent chips from clumping together. In addition, the thickness of the third passivation layer (143) may be thinner than the thickness of the first passivation layer (141). Accordingly, a step is formed on the side of the semiconductor light-emitting device, and when the semiconductor light-emitting device is assembled sideways, there is a technical effect of being easily removed to prevent incorrect assembly. In addition, when part of the passivation on the side of the semiconductor light-emitting device is removed for the side wiring process, the thin third passivation layer (143) is removed to enable side wiring connection, and the thick first passivation layer (141) remains without being removed, so there is a technical effect of being able to protect the active layer.

[0149]

[0150] A semiconductor light-emitting device according to an embodiment and a display device including the same have a technical effect of increasing an electrical contact area with a panel electrode in a side wiring process.

[0151] For example, the embodiment may form the passivation layer to expose a portion of the side surface of the first conductive semiconductor layer, thereby increasing the electrical contact area by allowing the side wiring to be connected to the first conductive semiconductor layer.

[0152] In addition, the embodiment has a technical effect that can prevent poor contact of side wiring.

[0153] For example, the embodiment can prevent the problem of poor contact during the wiring process by having a small contact area of ​​the side wiring.

[0154] In addition, the embodiment has a technical effect of preventing incorrect assembly during self-assembly of a semiconductor light-emitting device.

[0155] For example, the embodiment can prevent incorrect assembly by allowing the passivation layer to be easily removed during assembly to the side of the semiconductor light-emitting device through the shape of the passivation layer.

[0156] In addition, the embodiment has a technical effect of preventing oxidation of an electrode of a semiconductor light-emitting device.

[0157] For example, the embodiment can form a passivation layer under the electrode of a semiconductor light-emitting device to prevent oxidation of the electrode in fluid assembly.

[0158] Although the present invention has been described above with reference to embodiments thereof, it will be readily understood by those skilled in the art that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

[0159] The embodiment can be adopted in the field of displays that display images or information.

[0160] The embodiment can be adopted in the field of displays that display images or information using semiconductor light-emitting elements.

[0161] The embodiment can be adopted in the display field that displays images or information using micro- or nano-level semiconductor light-emitting elements.

Claims

1. A light-emitting structure comprising a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer; A first electrode disposed under the light-emitting structure; A second electrode disposed on the light-emitting structure; A semiconductor light-emitting element for a display pixel, comprising a first passivation layer arranged to extend to the side of the first conductive semiconductor layer on the second electrode.

2. In paragraph 1, A semiconductor light-emitting element for a display pixel, wherein the side surface of the first conductive semiconductor layer includes a first region in contact with the passivation layer and a second region not in contact with the passivation layer.

3. In paragraph 1, The above passivation layer is, A semiconductor light emitting element for a display pixel, further comprising a second passivation layer disposed under the first electrode.

4. In paragraph 1, The above passivation layer is, Further comprising a third passivation layer disposed in the second region, A semiconductor light-emitting element for a display pixel, wherein the thickness of the third passivation layer is thinner than the thickness of the first passivation layer.

5. Substrate; A semiconductor light emitting element for a display pixel arranged on the substrate; and It includes a first panel electrode and a second panel electrode connected to the semiconductor light emitting element, The semiconductor light-emitting device includes a first electrode, a first conductive semiconductor layer disposed on the first electrode, an active layer disposed on the first conductive semiconductor layer, a second conductive semiconductor layer disposed on the active layer, and a second electrode disposed on the second conductive semiconductor layer. Further comprising a passivation layer extending to the side of the first conductive semiconductor layer on the second electrode, A display device including a semiconductor light-emitting element, wherein the first panel electrode is connected to the first electrode of the semiconductor light-emitting element and the first conductive semiconductor layer.

6. In paragraph 5, The first conductive semiconductor layer includes a first region in contact with the passivation layer and a second region that is not in contact with the passivation layer, A display device including a semiconductor light-emitting element, wherein the second region is connected to the first panel electrode.

7. In paragraph 5, A display device including a semiconductor light emitting element, further comprising a second passivation layer disposed under the first electrode.

8. In paragraph 5, A display device including a semiconductor light-emitting element, wherein the substrate further includes a plurality of assembly wires spaced apart from each other, and further includes an insulating layer between the plurality of assembly wires and the semiconductor light-emitting element.

9. In paragraph 5, A display device including a semiconductor light-emitting element, further comprising an adhesive layer disposed between the substrate and the semiconductor light-emitting element.

10. In paragraph 9, The adhesive layer includes a first adhesive layer that vertically overlaps the semiconductor light-emitting element and a second adhesive layer that does not vertically overlap, A display device including a semiconductor light-emitting element, wherein the thickness of the second adhesive layer is thinner than the thickness of the first adhesive layer.

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