Pixel element for display, and display device having same

Abstract

The present invention relates to a pixel element for a display, and a display device having same. According to one embodiment, the pixel element comprises: a first light-emitting structure which is formed on a first base, and in which a 1-1 semiconductor layer, a first active layer and a 1-2 semiconductor layer are stacked; a second light-emitting structure which is formed on a first light-emitting unit, and in which a 2-1 semiconductor layer, a second active layer and a 2-2 semiconductor layer are stacked; a third light-emitting structure which is formed on a second light-emitting unit, and in which a 3-1 semiconductor layer, a third active layer, and a 3-2 semiconductor layer are stacked; a common electrode electrically connected to the 1-1 semiconductor layer, the 2-1 semiconductor layer and the 3-1 semiconductor layer at the same time; a first electrode electrically connected to the 1-2 semiconductor layer; a second electrode electrically connected to the 2-2 semiconductor layer; and a third electrode electrically connected to the 3-2 semiconductor layer. The common electrode and the first electrode are formed along one side surface of the 2-1 semiconductor layer and one side surface of the 3-1 semiconductor layer so as to be stair-structured.

Description

Pixel element for display and display device having the same

[0001] The present invention relates to a pixel element for a display and a display device having the same.

[0002] Light-emitting diodes (LEDs), semiconductor devices that utilize inorganic light sources, are widely used in various fields, including display devices, vehicle lamps, and general lighting. Light-emitting diodes (LEDs) are rapidly replacing existing light sources due to their long lifespan, low power consumption, and fast response times.

[0003] Meanwhile, conventional light-emitting diodes (LEDs) have primarily been used as backlight sources in display devices. Recently, display devices that directly display images using LEDs are being developed. These displays are also referred to as micro LED displays.

[0004] Display devices typically use a mixture of blue, green, and red to produce a variety of colors. To produce various images, display devices comprise multiple pixels, each of which has blue, green, and red sub-pixels. The colors of these sub-pixels determine the color of a specific pixel, and the combination of these pixels produces an image.

[0005] In addition, the pixel may have a structure in which a blue subpixel, a green subpixel, and a blue subpixel are sequentially stacked. In addition, each subpixel includes a light-emitting region in which a light-emitting structure is formed and a non-light-emitting region in which the light-emitting structure is omitted. When multiple subpixels are stacked, the light-emitting region of another subpixel may be positioned above the non-light-emitting region of one subpixel. In this case, deformation may occur in the non-light-emitting region located below due to the weight of the light-emitting region in which the light-emitting structure located above is formed. Ultimately, deformation such as bending may occur in the pixel element.

[0006] Furthermore, in the case of micro LED displays, micro LEDs are arranged on a plane corresponding to each subpixel, and numerous micro LEDs are mounted on a single substrate. However, micro LEDs are extremely small, less than 200㎛ or even 100㎛, so their effective light-emitting area is limited. Furthermore, electrodes for electrical connection to small light-emitting elements are essential, reducing the light-emitting area and potentially resulting in loss of brightness.

[0007] The problem to be solved by the present invention is to provide a pixel element capable of minimizing reduction in light-emitting area and a display device having the pixel element.

[0008] In addition, the problem to be solved by the present invention is to provide a pixel element having a uniform amount of light for each color and a display device having the pixel element.

[0009] In addition, the problem to be solved by the present invention is to provide a pixel element capable of simplifying the manufacturing process and a display device having the pixel element.

[0010] In addition, the problem to be solved by the present invention is to provide a pixel element capable of preventing deformation and a display device having the same.

[0011] In addition, another problem to be solved by the present invention is to provide a pixel element capable of preventing delamination between components and a display device having the pixel element.

[0012] According to one embodiment of the present invention, a pixel device may include a first light-emitting unit including a first light-emitting structure formed by stacking a first semiconductor layer, a first active layer, and a first semiconductor layer formed on a first base; a second light-emitting unit formed on the first light-emitting unit and including a second light-emitting structure formed by stacking a second semiconductor layer, a second active layer, and a second semiconductor layer; and a third light-emitting unit formed on the second light-emitting unit and including a third light-emitting structure formed by stacking a third semiconductor layer, a third active layer, and a third semiconductor layer; a common electrode electrically connected simultaneously to the first semiconductor layer, the second semiconductor layer, and the third semiconductor layer; a first electrode electrically connected to the first semiconductor layer; a second electrode electrically connected to the second semiconductor layer; and a third electrode electrically connected to the third semiconductor layer. The common electrode, the first electrode, the second electrode, and the third electrode may be formed to be spaced apart from each other. The inner surface of the 3-1 semiconductor layer may be formed further outward than the inner surface of the 2-1 semiconductor layer. The common electrode and the first electrode may be formed along one side of the 2-1 semiconductor layer and one side of the 3-1 semiconductor layer to have a step structure.

[0013] The first light emitting unit, the second light emitting unit, and the third light emitting unit can emit visible light of different colors.

[0014] The pixel element may further include a first transparent layer formed between the first light-emitting portion and the second light-emitting portion; and a second transparent layer formed between the second light-emitting portion and the third light-emitting portion.

[0015] The common electrode may be electrically connected to the 2-1 semiconductor layer and the 1-1 semiconductor layer by penetrating the first transparent layer and the second transparent layer. The first electrode may be electrically connected to the 1-2 semiconductor layer by penetrating the first transparent layer and the second transparent layer. The second electrode may be electrically connected to the 2-2 semiconductor layer by penetrating the second transparent layer.

[0016] The common electrode and the first electrode may be positioned on different vertical lines, such that the central axis of the portion formed on the first light-emitting portion, the central axis of the portion formed on the second light-emitting portion, and the central axis of the portion formed on the third light-emitting portion are different from each other.

[0017] The first light-emitting portion may further include a first insulating layer covering the first light-emitting structure, the second light-emitting portion may further include a second insulating layer covering the second light-emitting structure, and the third light-emitting portion may further include a third insulating layer covering the third light-emitting structure.

[0018] The common electrode may include a 1-1 metal layer electrically connected to the 1-1 semiconductor layer; a 2-1 metal layer electrically connected to the 2-1 semiconductor layer; and a 3-1 metal layer electrically connected to the 3-1 semiconductor layer. The 2-1 metal layer may be formed from the 1-1 metal layer along the inner surface of the 2-1 semiconductor layer to the upper surface of the 2-1 semiconductor layer. The 3-1 metal layer may be formed from the upper surface of the 2-1 metal layer along the inner surface of the 3-1 semiconductor layer to the upper surface of the 3-1 semiconductor layer.

[0019] The first insulating layer may include a 1-1 opening through which the 1-1 semiconductor layer and the 1-1 metal layer are connected, the second insulating layer may include a 2-3 opening through which the 1-2 semiconductor layer and the 2-1 metal layer are connected, and the third insulating layer may include a 3-3 opening through which the 3-1 semiconductor layer and the 3-1 metal layer are connected. The 2-3 opening may be located on an upper portion of an outer side of the 1-1 opening, and the 3-3 opening may be located on an upper portion of an outer side of the 2-3 opening.

[0020] The pixel element may include a 2-1 opening through which the 1-1 metal layer and the 2-1 metal layer are connected; and a 3-1 opening through which the 2-1 metal layer and the 3-1 metal layer are connected. The 2-1 opening may be positioned on an upper portion of the first insulating layer and may be formed through the first transparent layer and the second insulating layer to expose a portion of an upper surface of the 1-1 metal layer. The 3-1 opening may be positioned on an upper portion of the second insulating layer and may be formed through the second transparent layer and the third insulating layer to expose a portion of an upper surface of the 2-1 metal layer.

[0021] In one embodiment, the 2-1 metal layer may be formed to cover the inner surface of the 2-1 opening, but may be formed to expose the upper surface of the 1-1 metal layer. The 3-1 metal layer may be formed to cover the inner surface of the 3-1 opening, but may be formed to expose the upper surface of the 2-1 metal layer.

[0022] In another embodiment, the 2-1 metal layer may be formed to further cover the upper surface of the 1-1 metal layer in the 2-1 opening, and may be formed to have an internal space in the 2-1 opening. The 3-1 metal layer may be formed to further cover the upper surface of the 2-1 metal layer in the 3-1 opening, and may be formed to have an internal space in the 3-1 opening.

[0023] In another embodiment, the 2-1 metal layer may be formed to fill the 2-1 opening, and the 3-1 metal layer may be formed to fill the 3-1 opening.

[0024] The first electrode may include a 1-2 metal layer electrically connected to the 1-2 semiconductor layer; a 2-2 metal layer formed from an upper surface of the 1-2 metal layer along an inner surface of the second light-emitting structure to an upper portion of the 2-2 semiconductor layer; and a 3-2 metal layer formed from an upper surface of the 2-2 metal layer along an inner surface of the third light-emitting structure to an upper portion of the 3-2 semiconductor layer.

[0025] The first insulating layer may include a first-second opening through which the first-second semiconductor layer and the first-second metal layer are connected, the second insulating layer may include a second-second opening through which the first-second metal layer and the second-second metal layer are connected, and the third insulating layer may include a third-second opening through which the second-second metal layer and the third-second metal layer are connected. The second-second opening may be located on an upper portion of an outer side of the first-second opening, and the third-second opening may be located on an upper portion of an outer side of the second-second opening.

[0026] The above 2-2 opening is located on the upper portion of the first insulating layer and may be formed by penetrating the first transparent layer and the second insulating layer so as to expose a portion of the upper surface of the 1-2 metal layer. The above 3-2 opening is located on the upper portion of the second insulating layer and may be formed by penetrating the second transparent layer and the third insulating layer so as to expose a portion of the upper surface of the 2-2 metal layer.

[0027] In one embodiment, the 2-2 metal layer may be formed to cover the inner surface of the 2-2 opening, while exposing the upper surface of the 1-2 metal layer. The 3-2 metal layer may be formed to cover the inner surface of the 3-2 opening, while exposing the upper surface of the 2-2 metal layer.

[0028] In another embodiment, the 2-2 metal layer may be formed to further cover the upper surface of the 1-2 metal layer in the 2-2 opening, and may be formed to have an internal space in the 2-2 opening. The 3-2 metal layer may be formed to further cover the upper surface of the 2-2 metal layer in the 3-2 opening, and may be formed to have an internal space in the 3-2 opening.

[0029] In another embodiment, the 2-2 metal layer may be formed to fill the 2-2 opening, and the 3-2 metal layer may be formed to fill the 3-2 opening.

[0030] The second electrode may include a 2-3 metal layer electrically connected to the 2-2 semiconductor layer; and a 3-3 metal layer formed from the upper surface of the 2-3 metal layer along the inner surface of the third light-emitting structure to the upper portion of the 3-2 semiconductor layer.

[0031] The second insulating layer includes a 2-4 opening that connects the 2-2 semiconductor layer and the 2-3 metal layer, the third insulating layer includes a 3-4 opening that connects the 2-3 metal layer and the 3-3 metal layer, and the 3-4 opening can be located on the outer upper side of the 2-4 opening.

[0032] The above 3-4 opening is located on the upper portion of the second insulating layer and can be formed by penetrating the second transparent layer and the third insulating layer so as to expose a portion of the upper surface of the 2-3 metal layer.

[0033] In one embodiment, the 3-3 metal layer may be formed to cover the inner surface of the 3-4 opening, but may be formed to expose the upper surface of the 2-3 metal layer.

[0034] In another embodiment, the 3-3 metal layer may be formed to further cover the upper surface of the 2-3 metal layer in the 3-4 opening, and may be formed to have an internal space in the 3-4 opening.

[0035] In another embodiment, the 3-3 metal layer may be formed to fill the 3-4 opening.

[0036] The third electrode may include a third-fourth metal layer electrically connected to the third-third semiconductor layer.

[0037] The third insulating layer may include a third-fifth opening through which the third-third semiconductor layer and the third-fourth metal layer are connected.

[0038] According to another embodiment of the present invention, a pixel device is provided, which includes a first light-emitting unit, a second light-emitting unit, and a third light-emitting unit. The first light-emitting unit may include a first light-emitting structure that emits a first light and a first buffer structure formed to be spaced apart from the first light-emitting structure. The second light-emitting unit may include a second light-emitting structure that emits the second light and a second buffer structure formed to be spaced apart from the second light-emitting structure. The third light-emitting unit may include a third light-emitting unit that includes a third light-emitting structure that emits the third light and a third buffer structure formed to be spaced apart from the third light-emitting structure. The second light-emitting unit is laminated on the first light-emitting unit, and the third light-emitting unit is laminated on the second light-emitting unit. The first light-emitting unit, the second light-emitting unit, and the third light-emitting unit each include a first semiconductor layer, an active layer, and a second semiconductor layer. In addition, the first buffer structure, the second buffer structure, and the third buffer structure are respectively disposed in the non-light-emitting areas of the first light-emitting portion, the second light-emitting portion, and the third light-emitting portion, and are in an insulated state.

[0039] The first light emitting unit, the second light emitting unit, and the third light emitting unit can emit visible light of different colors.

[0040] The first light-emitting portion may include a first semiconductor layer, a first semiconductor layer, and a first active layer formed between the first semiconductor layer and the first semiconductor layer. The second light-emitting portion may include a second semiconductor layer, a second semiconductor layer, and a second active layer formed between the second semiconductor layer and the second semiconductor layer. In addition, the third light-emitting portion may include a third semiconductor layer, a third semiconductor layer, and a third active layer formed between the third semiconductor layer and the third semiconductor layer.

[0041] The first light-emitting structure may include the first active layer and the 1-2 semiconductor layer formed on top of the 1-1 semiconductor layer. The second light-emitting structure may include the second active layer and the 2-2 semiconductor layer formed on top of the 2-1 semiconductor layer. In addition, the third light-emitting structure may include the third active layer and the 3-2 semiconductor layer formed on top of the 3-1 semiconductor layer.

[0042] The first buffer structure may include the first active layer and the 1-2 semiconductor layer formed on top of the 1-1 semiconductor layer. The second buffer structure may include the second active layer and the 2-2 semiconductor layer formed on top of the 2-1 semiconductor layer. In addition, the third buffer structure may include the third active layer and the 3-2 semiconductor layer formed on top of the 3-1 semiconductor layer.

[0043] The pixel element may include a common electrode electrically connected to all of the 1-1 semiconductor layer, the 2-1 semiconductor layer, and the 3-1 semiconductor layer, a first electrode electrically connected to the 1-2 semiconductor layer, a second electrode electrically connected to the 2-2 semiconductor layer, and a third electrode electrically connected to the 3-2 semiconductor layer.

[0044] The pixel element may include a first transparent layer disposed between the first light-emitting portion and the second light-emitting portion, and a second transparent layer disposed between the second light-emitting portion and the third light-emitting portion.

[0045] The common electrode may be electrically connected to the 1-1 semiconductor layer and the 2-1 semiconductor layer by penetrating the first transparent layer and the second transparent layer. The first electrode may be electrically connected to the 1-2 semiconductor layer by penetrating the first transparent layer and the second transparent layer. In addition, the second electrode may be electrically connected to the 2-2 semiconductor layer by penetrating the second transparent layer.

[0046] The common electrode may include a first metal layer, a first connection metal layer, a second metal layer, a second connection metal layer, and a third metal layer. The first metal layer may be formed on the first semiconductor layer of the first light-emitting portion and may be in contact with the first semiconductor layer. The first connection metal layer may penetrate the first transparent layer and be in contact with the first metal layer. The second metal layer may penetrate the second semiconductor layer of the second light-emitting portion and be in contact with the second semiconductor layer. The second connection metal layer may penetrate the second transparent layer and be in contact with the second metal layer. The third metal layer may penetrate the third semiconductor layer of the third light-emitting portion and be in contact with the third semiconductor layer. At least a portion of the first connection metal layer may be located on the first metal layer. At least a portion of the 2-1 metal layer may be positioned on top of the 1-1 connecting metal layer. At least a portion of the 2-1 connecting metal layer may be positioned on top of the 2-1 metal layer. Additionally, at least a portion of the 3-1 metal layer may be positioned on top of the 2-1 connecting metal layer.

[0047] The first electrode may include a first metal layer, a first connection metal layer, a second metal layer, a second connection metal layer, and a third metal layer. The first metal layer may be formed on the first semiconductor layer of the first light-emitting portion and may be electrically connected to the first semiconductor layer. The first connection metal layer may penetrate the first transparent layer and be in contact with the first metal layer. The second metal layer may penetrate the second semiconductor layer of the second light-emitting portion and be insulated from the second semiconductor layer. The second connection metal layer may penetrate the second transparent layer and be in contact with the second metal layer. The third metal layer may penetrate the third semiconductor layer of the third light-emitting portion and be insulated from the third semiconductor layer. At least a portion of the first connection metal layer may be located on the first metal layer. At least a portion of the second-second metal layer may be positioned on top of the first-second connection metal layer. At least a portion of the second-second connection metal layer may be positioned on top of the second-second metal layer. Furthermore, at least a portion of the third-second metal layer may be positioned on top of the second-second connection metal layer.

[0048] The second electrode may include a 2-3 metal layer, a 2-3 connection metal layer, and a 3-3 metal layer. The 2-3 metal layer may be formed on the 2-2 semiconductor layer of the second light-emitting portion and may be electrically connected to the 2-2 semiconductor layer. The 2-3 connection metal layer may penetrate the second transparent layer and be in contact with the 2-3 metal layer. The 3-3 metal layer may penetrate the 3-1 semiconductor layer of the third light-emitting portion and may be insulated from the 3-1 semiconductor layer. At least a portion of the 2-3 connection metal layer may be located on the 2-3 metal layer. In addition, at least a portion of the 3-3 metal layer may be located on the 2-3 connection metal layer.

[0049] The third electrode may include a third-fourth metal layer formed on top of the third-second semiconductor layer of the third light-emitting portion and electrically connected to the third-second semiconductor layer.

[0050] A portion of the second light-emitting structure may be positioned above the first light-emitting structure, and a portion of the third light-emitting structure may be positioned above the second light-emitting structure.

[0051] The first buffer structure, the second buffer structure, and the third buffer structure may be formed in an outer region of an area where the first light-emitting structure, the second light-emitting structure, and the third light-emitting structure are all laminated.

[0052] The common electrode, the first electrode, the second electrode, and the third electrode may be formed in an outer region of an area where the first light-emitting structure, the second light-emitting structure, and the third light-emitting structure are all laminated.

[0053] A pixel element and a display device having the same according to an embodiment of the present invention can improve light emission efficiency by minimizing a reduction in light emission area by forming an electrode on the outside of a light emitting structure.

[0054] In addition, the pixel element and the display device having the same according to an embodiment of the present invention can form the light emitting area for each color of light equally, thereby making the amount of light for each color uniform.

[0055] In addition, the pixel element and the display device having the same according to an embodiment of the present invention can simplify the manufacturing process by forming an opening for forming an electrode in a layer made of the same material.

[0056] In addition, the pixel element and the display device having the same according to an embodiment of the present invention can prevent deformation of the pixel element, such as bending.

[0057] In addition, the pixel element and the display device having the same according to an embodiment of the present invention can prevent peeling between the stacked components by forming the upper surface of the component located at the bottom flat.

[0058] FIG. 1 is a schematic plan view illustrating a display device according to one embodiment of the present invention.

[0059] FIG. 2 is a schematic plan view of a pixel element according to a first embodiment of the present invention.

[0060] FIG. 3 is a cross-sectional view (A1-A2) illustrating a pixel element according to a first embodiment of the present invention.

[0061] FIG. 4 is another cross-sectional view (A3-A4) for explaining a pixel element according to the first embodiment of the present invention.

[0062] FIGS. 5 to 39 are drawings for explaining a method for manufacturing a pixel element according to a first embodiment of the present invention.

[0063] FIG. 40 is a schematic plan view of a pixel element according to a second embodiment of the present invention.

[0064] FIG. 41 is a cross-sectional view (G1-G2) illustrating a pixel element according to a second embodiment of the present invention.

[0065] FIG. 42 is another cross-sectional view (G3-G4) for explaining a pixel element according to a second embodiment of the present invention.

[0066] Figure 43 is a schematic plan view of a pixel element according to a third embodiment of the present invention.

[0067] FIG. 44 is a cross-sectional view (H1-H2) illustrating a pixel element according to a third embodiment of the present invention.

[0068] FIG. 45 is another cross-sectional view (H3-H4) for explaining a pixel element according to a third embodiment of the present invention.

[0069] FIG. 46 is a cross-sectional view illustrating a pixel element according to a fourth embodiment of the present invention.

[0070] FIG. 47 is another cross-sectional view illustrating a pixel element according to a fourth embodiment of the present invention.

[0071] FIGS. 48 to 52 are drawings for explaining a first light-emitting portion of a pixel element of a fifth embodiment of the present invention and a manufacturing method thereof.

[0072] FIGS. 53 to 57 are drawings for explaining a second light-emitting portion of a pixel element of the fifth embodiment of the present invention and a manufacturing method thereof.

[0073] FIGS. 58 to 62 are drawings for explaining the third light-emitting portion of the pixel element of the fifth embodiment of the present invention and the manufacturing method thereof.

[0074] Fig. 63 is a drawing showing a first transparent layer formed on the upper part of a first light-emitting portion according to a fifth embodiment of the present invention.

[0075] FIG. 64 is a drawing showing a first connecting metal layer formed on a first transparent layer according to a fifth embodiment of the present invention.

[0076] FIG. 65 is a drawing showing a second light emitting unit with the second base removed according to the fifth embodiment of the present invention.

[0077] FIG. 66 is a drawing showing a first light-emitting unit and a second light-emitting unit stacked on top of the first light-emitting unit according to a fifth embodiment of the present invention.

[0078] Fig. 67 is a drawing showing a second transparent layer formed on the upper part of a second light-emitting portion according to the fifth embodiment of the present invention.

[0079] FIG. 68 is a drawing showing a second connecting metal layer formed on a second transparent layer according to a fifth embodiment of the present invention.

[0080] Fig. 69 is a drawing showing a third light-emitting unit with the third base removed according to the fifth embodiment of the present invention.

[0081] FIG. 70 is a drawing showing a pixel element including a first light-emitting portion, a second light-emitting portion stacked on top of the first light-emitting portion, and a third light-emitting portion stacked on top of the second light-emitting portion according to a fifth embodiment of the present invention.

[0082] FIG. 71 is a drawing showing a pixel element having a protective layer formed thereon according to a fifth embodiment of the present invention.

[0083] Hereinafter, the pixel element for display of the present invention and the display device having the same will be described in detail through drawings.

[0084] FIG. 1 is a schematic plan view illustrating a display device according to one embodiment of the present invention.

[0085] Referring to FIG. 1, a display device (1) may include a panel substrate (11) and a plurality of pixel modules (10).

[0086] The display device (1) may include, but is not particularly limited to, a wearable display device (1) such as a smart watch, VR headset or glasses, an AR display device (1) such as augmented reality glasses, or an indoor or outdoor display device (1) such as a micro LED TV or signage.

[0087] A panel substrate (11) and a plurality of pixel modules (10) can be arranged within a display device (1). Here, each pixel module (10) can be a pixel of the display device (1).

[0088] The display device (1) may have a very narrow gap between pixels, for example, the gap between pixels may be 0.01 mm or less. The display device (1) can implement an image through pixels mounted on a circuit board (1001) or a transparent substrate.

[0089] In some display devices (1), the distance between an external receiver (e.g., a user's eyes) that recognizes the display and the display device (1) may be less than 200 mm. The gap between pixels may be 0.005 to 0.1% of the distance between the external receiver and the display device (1).

[0090] The display device (1) can send an optical signal to an external receiver from a substrate including a curved surface. The display device (1) can also be a transparent display device (1) using a transparent substrate.

[0091] The panel substrate (11) may include circuitry for passive matrix driving or active matrix driving. In one embodiment, the panel substrate (11) may include wiring and resistors therein, and in another embodiment, the panel substrate (11) may include wiring, transistors, and capacitors. The panel substrate (11) may also have pads on its upper surface that can be electrically connected to the arranged circuitry.

[0092] In one embodiment, a plurality of pixel modules (10) are aligned on a panel substrate (11). Each pixel module (10) may include a circuit board (1001) and a plurality of pixel elements (1000) arranged on the circuit board (1001). In addition, the pixel module (10) may include a molding portion (not shown) covering the pixel elements (1000). In another embodiment, a plurality of pixel elements (1000) may be arranged directly on the panel substrate (11), and the molding portion may cover the pixel elements (1000).

[0093] FIGS. 2 to 4 are drawings for explaining a pixel device (1000) according to a first embodiment of the present invention. FIG. 2 is a schematic plan view of a pixel device (1000) according to a first embodiment of the present invention. FIG. 3 is a cross-sectional view (A1-A2) for explaining a pixel device (1000) according to a first embodiment of the present invention. In addition, FIG. 4 is another cross-sectional view (A3-A4) for explaining a pixel device (1000) according to a first embodiment of the present invention.

[0094] Referring to FIGS. 2 to 4, a pixel element (1000) according to a first embodiment of the present invention may include a first base (1110), a first light-emitting portion (1100), a second light-emitting portion (1200), and a third light-emitting portion (1300).

[0095] The first light-emitting unit (1100) may have a structure in which a first-first semiconductor layer (1121), a first active layer (1122), and a first-second semiconductor layer (1123) are sequentially stacked. The second light-emitting unit (1200) may have a structure in which a second-first semiconductor layer (1221), a second active layer (1222), and a second-second semiconductor layer (1223) are sequentially stacked. In addition, the third light-emitting unit (1300) may have a structure in which a third-first semiconductor layer (1321), a third active layer (1322), and a third-second semiconductor layer (1323) are sequentially stacked. Here, the first-first semiconductor layer (1121), the second-first semiconductor layer (1221), and the third-first semiconductor layer (1321) may be n-type semiconductor layers. Additionally, the first-second semiconductor layer (1123), the second-second semiconductor layer (1223), and the third-second semiconductor layer (1323) may be p-type semiconductor layers. Or vice versa.

[0096] For example, the first light emitting unit (1100) can emit green light, the second light emitting unit (1200) can emit blue light, and the third light emitting unit (1300) can emit red light.

[0097] In addition, the pixel element (1000) has a structure in which a first light-emitting portion (1100), a second light-emitting portion (1200), and a third light-emitting portion (1300) are sequentially stacked on a first base (1110). A transparent layer (1070) may be formed between the first light-emitting portion (1100) and the second light-emitting portion (1200) and between the second light-emitting portion (1200) and the third light-emitting portion (1300), respectively. The transparent layer (1070) may be formed of a material that transmits light. In addition, the transparent layer (1070) may be formed of a material that transmits and scatters light. Alternatively, the transparent layer (1070) may be a resin that transmits light and a material that scatters light is dispersed therein.

[0098] A first transparent layer (1170) may be formed between the first light-emitting unit (1100) and the second light-emitting unit (1200), and a second transparent layer (1270) may be formed between the second light-emitting unit (1200) and the third light-emitting unit (1300). The first transparent layer (1170) may transmit light emitted from the second light-emitting unit (1200) and the third light-emitting unit (1300). In addition, the second transparent layer (1270) may transmit light emitted from the third light-emitting unit (1300).

[0099] Additionally, the transparent layer (1070) may have an adhesive function. Accordingly, the pixel element (1000) can maintain a structure in which the first light-emitting portion (1100), the second light-emitting portion (1200), and the third light-emitting portion (1300) are laminated by the first transparent layer (1170) and the second transparent layer (1270).

[0100] The pixel element (1000) of the present embodiment may include a metal layer (1060) for electrical connection with the first light-emitting unit (1100), the second light-emitting unit (1200), and the third light-emitting unit (1300). At this time, the first light-emitting unit (1100), the second light-emitting unit (1200), and the third light-emitting unit (1300) may include an insulating layer (1050) to prevent unnecessary electrical connection with the metal layer (1060). In addition, an opening (1059) may be formed in the insulating layer (1050) so that the first light-emitting unit (1100), the second light-emitting unit (1200), and the third light-emitting unit (1300) can be electrically connected with the metal layer (1060).

[0101] The insulating layer (1050) may include a first insulating layer (1150) of the first light-emitting portion (1100), a second insulating layer (1250) of the second light-emitting portion (1200), and a third insulating layer (1350) of the third light-emitting portion (1300). In addition, a first transparent layer (1170) may be formed between the first light-emitting portion (1100) and the second light-emitting portion (1200), and a second transparent layer (1270) may be formed between the second light-emitting portion (1200) and the third light-emitting portion (1300).

[0102] Referring to FIGS. 3 and 4, a first opening (1159) is formed in the first insulating layer (1150), and the first opening (1159) includes a first-first opening (1151) and a first-second opening (1152).

[0103] A second opening (1259) is formed in the second insulating layer (1250) and the first transparent layer (1170). The second opening (1259) includes a 2-3 opening (1253) and a 2-4 opening (1254) formed in the second insulating layer (1250), and includes a 2-1 opening (1251) and a 2-2 opening (1252) formed in the second insulating layer (1250) and the first transparent layer (1170).

[0104] According to an embodiment of the present invention, a portion of the second metal layer (1260) is formed to cover a portion of the second insulating layer (1250). In addition, a portion of the first transparent layer (1170) may be positioned between the first metal layer (1160) and the second metal layer (1260). Furthermore, a portion of the second insulating layer (1250) and a portion of the first transparent layer (1170) may be positioned between the first metal layer (1160) and the second metal layer (1260) at the same time. That is, a portion of the second insulating layer (1250) and a portion of the first transparent layer (1170) may be simultaneously embedded between the first metal layer (1160) and the second metal layer (1260). At this time, a portion of the second insulating layer (1250) is laminated on the upper surface of the first transparent layer (1170). The bonding strength between the second insulating layer (1250) and the first transparent layer (1170) can be improved by the first metal layer (1160) and the second metal layer (1260) that simultaneously fill a portion of the second insulating layer (1250) and a portion of the second transparent layer (1170).

[0105] Additionally, a third opening (1359) is formed in the third insulating layer (1350) and the second transparent layer (1270). The third opening (1359) includes a 3-3 opening (1353) and a 3-5 opening (1355) formed in the third insulating layer (1350), and a 3-1 opening (1351), a 3-2 opening (1352), and a 3-4 opening (1354) formed in the third insulating layer (1350) and the second transparent layer (1270).

[0106] A portion of the third insulating layer (1350) and a portion of the second transparent layer (1270) may also be embedded between the second metal layer (1260) and the third metal layer (1360) in a laminated state. Accordingly, the bonding strength between the third insulating layer (1350) and the second transparent layer (1270) may be improved by the second metal layer (1260) and the third metal layer (1360) that simultaneously embed a portion of the third insulating layer (1350) and a portion of the second transparent layer (1270).

[0107] Referring to FIG. 3, the first-first opening (1151), the second-first opening (1251), the second-third opening (1253), the third-first opening (1351), and the third-third opening (1353) may be formed so that their respective central axes are positioned on different vertical lines. Furthermore, the first-first opening (1151), the second-first opening (1251), the second-third opening (1253), the third-first opening (1351), and the third-third opening (1353) may be positioned so as to deviate from each other.

[0108] Additionally, the second-fourth opening (1254) and the third-fourth opening (1354) may be formed so that their respective central axes are positioned on different vertical lines. Furthermore, the third-fourth opening (1354) may be formed at an upper portion away from the second-fourth opening (1254).

[0109] Referring to FIG. 4, the first-second opening (1152), the second-second opening (1252), and the third-second opening (1352) may be formed so that their respective central axes are positioned on different vertical lines. Furthermore, the first-second opening (1152), the second-second opening (1252), and the third-second opening (1352) may be positioned so as to deviate from each other.

[0110] A first metal layer (1160) may be formed in the first light-emitting portion (1100), a second metal layer (1260) may be formed in the second light-emitting portion (1200), and a third metal layer (1360) may be formed in the third light-emitting portion (1300).

[0111] The first metal layer (1160) may include a 1-1 metal layer (1161) and a 1-2 metal layer (1162). The second metal layer (1260) may include a 2-1 metal layer to a 2-3 metal layer (1261, 1262, 1263). In addition, the third metal layer (1360) may include a 3-1 metal layer to a 3-4 metal layer (1361, 1362, 1363, 1364).

[0112] Referring to FIG. 3, the 1-1 metal layer (1161) is formed on the 1st light-emitting portion (1100) and is electrically connected to the 1-1 semiconductor layer (1121) of the 1st light-emitting portion (1100). In addition, the 1-1 metal layer (1161) may be formed on the 2nd light-emitting portion (1200) and electrically connected to the 2-1 metal layer (1261) that is electrically connected to the 2-1 semiconductor layer (1221). In addition, the 2-1 metal layer (1261) may be formed on the 3rd light-emitting portion (1300) and electrically connected to the 3-1 metal layer (1361) that is electrically connected to the 3-1 semiconductor layer (1321). That is, the first-first semiconductor layer (1121), the second-first semiconductor layer (1221), and the third-first semiconductor layer (1321) can be electrically connected by the first-first metal layer (1161), the second-first metal layer (1261), and the third-first metal layer (1361). Here, the first-first metal layer (1161), the second-first metal layer (1261), and the third-first metal layer (1361) can be a common electrode commonly connected to the first semiconductor layers of the first light-emitting portion (1100), the second light-emitting portion (1200), and the third light-emitting portion (1300). Here, the first semiconductor layers are the 1-1 semiconductor layer (1121) of the first light-emitting portion (1100), the 2-1 semiconductor layer (1221) of the second light-emitting portion (1200), and the 3-1 semiconductor layer (1321) of the third light-emitting portion (1300).

[0113] Referring to FIG. 2, an imaginary horizontal center line (A5) and a vertical center line (A6) crossing the center of the pixel element (1000) are illustrated.

[0114] The pixel element (1000) can be divided into one side and the other side based on the horizontal center line (A5) illustrated in FIG. 2. Referring to FIG. 2, metal layers (1060) are distributed and arranged on one side and the other side of the horizontal center line (A5). A light-emitting area can be formed between the metal layers (1060) distributed and arranged on the one side and the other side. The light-emitting area can be an area where at least two of the first light-emitting unit (1100), the second light-emitting unit (1200), and the third light-emitting unit (1300) overlap. Furthermore, the light-emitting area can be a part or the entire area where the first light-emitting unit (1100), the third light-emitting unit (1200), and the third light-emitting unit (1300) all overlap.

[0115] Referring to Fig. 2, the width (W5) of the light-emitting area on the horizontal center line (A5) and the width (W6) of the light-emitting area on the vertical center line (A6) may be different. For example, the width (W5) of the light-emitting area on the vertical center line (A5) may be narrower than the width (W6) of the light-emitting area on the horizontal center line (A6).

[0116] According to the present embodiment, a part of one side of the 3-1 semiconductor layer (1321) on which the 3-1 metal layer (1361) is formed is located further outward than a part of one side of the 2-1 semiconductor layer (1221) on which the 2-1 metal layer (1261) is formed. By this structure, the 1-1 metal layers to the 3-1 metal layers (1161, 1261, 1361) connected to each other can be formed in a step structure.

[0117] In addition, the 2-1 metal layer (1261) is in contact with the upper surface of the 1-1 metal layer (1161) located outside the 1-1 opening (1151) in the 1-1 metal layer (1161). That is, the 2-1 metal layer (1261) is in contact with the upper surface of the 1-1 metal layer (1161) located on the upper side of the first insulating layer (1150). In addition, the 3-1 metal layer (1361) is also in contact with the upper surface of the 2-1 metal layer (1261) located on the upper side of the second insulating layer (1250).

[0118] The portion of the upper surface of the 1-1 metal layer (1161) located above the 1-1 opening (1151) and the portion of the upper surface of the 2-1 metal layer (1261) located above the 2-3 opening (1253) may be concave or convex compared to other portions of the upper surface due to the respective openings (1151, 1253). Therefore, for a stable process, the 2-1 metal layer (1261) may be formed to be in contact with the flat portion of the upper surface of the 1-1 metal layer (1161), and the 3-1 metal layer (1361) may be formed to be in contact with the flat portion of the upper surface of the 2-1 metal layer (1261). Accordingly, a part of the 2-1 metal layer (1261) may be formed on the 1-1 metal layer (1161) located on top of the 1st insulating layer (1150), and a part of the 3-1 metal layer (1361) may be formed on the 2-1 metal layer (1261) located on top of the 2nd insulating layer (1250).

[0119] Referring to FIG. 4, the first-second metal layer (1162) is formed on the first light-emitting portion (1100) and is electrically connected to the first-second semiconductor layer (1123) of the first light-emitting portion (1100). Here, the first-second metal layer (1162) is electrically connected to the first-second semiconductor layer (1123) through the first ohmic electrode (1130) formed on the first-second semiconductor layer (1123). In addition, the first-second metal layer (1162) may be electrically connected to the second-second metal layer (1262) formed on the second light-emitting portion (1200). In addition, the second-second metal layer (1262) may be electrically connected to the third-second metal layer (1362) formed on the third light-emitting portion (1300). In this way, the first-second metal layer (1162), the second-second metal layer (1262), and the third-first metal layer (1361) can be a first electrode electrically connected to the first-second semiconductor layer (1123), which is a P-type semiconductor layer of the first light-emitting portion (1100). The first electrode can be a P-type electrode of the first light-emitting portion (1100).

[0120] According to the present embodiment, the first to third metal layers (1162, 1262, 1362) may also be formed in a step structure by a structure in which a part of the side surface of the third semiconductor layer (1323) is located further outward than a part of the side surface of the second semiconductor layer (1223).

[0121] The portion of the upper surface of the 1-2 metal layer (1162) located above the 1-2 opening (1152) may be concave or convex compared to other portions of the upper surface due to the 1-2 opening (1152). Therefore, for a stable process, the 2-2 metal layer (1262) may be formed to contact a flat portion of the upper surface of the 1-2 metal layer (1162) located on the first insulating layer (1150). In addition, the 3-2 metal layer (1362) may be formed to contact a flat portion of the upper surface of the 2-2 metal layer (1262) located on the second insulating layer (1250).

[0122] Referring to FIG. 3, the 2-3 metal layer (1263) is formed on the second light-emitting portion (1200) and is electrically connected to the 2-2 semiconductor layer (1223) of the second light-emitting portion (1200). Here, the 2-3 metal layer (1263) can be electrically connected to the 2-2 semiconductor layer (1223) through the second ohmic electrode (1230) formed on the 2-2 semiconductor layer (1223). In addition, the 2-3 metal layer (1263) can be electrically connected to the 3-3 metal layer (1363) formed on the 3 light-emitting portion (1300). In this way, the 2-3 metal layer (1263) and the 3-3 metal layer (1363) can be second electrodes that are electrically connected to the 2-2 semiconductor layer (1223), which is a P-type semiconductor layer of the second light-emitting portion (1200). The second electrode may be a p-type electrode of the second light-emitting unit (1200).

[0123] According to the present embodiment, the 2nd-3rd metal layer (1263) and the 3rd-3rd metal layer (1363) can be formed in a step structure.

[0124] The portion of the upper surface of the 2-3 metal layer (1263) located above the 2-4 opening (1254) may be concave or convex compared to other portions of the upper surface due to the 2-4 opening (1254). Therefore, for a stable process, the 3-3 metal layer (1363) may be formed to contact a flat portion of the upper surface of the 2-3 metal layer (1263) located above the second insulating layer (1250).

[0125] Referring to FIG. 4, the 3-4 metal layer (1364) may be formed on the 3rd light-emitting portion (1300) and electrically connected to the 3-2 semiconductor layer (1323). Here, the 3-4 metal layer (1364) may be electrically connected to the 3-2 semiconductor layer (1323) through the 3rd ohmic electrode (1330) formed on the upper portion of the 3-2 semiconductor layer (1323). That is, the 3-4 metal layer (1364) may be a third electrode electrically connected to the 3-2 semiconductor layer (1323), which is a p-type semiconductor layer of the 3rd light-emitting portion (1300). The third electrode may be a p-type electrode of the 3rd light-emitting portion (1300).

[0126] A portion of the upper surface of the 3-4 metal layer (1364) located above the 3-5 opening (1355) may be more concave or convex than other portions due to the 3-5 opening (1355).

[0127] According to an embodiment of the present invention, the metal layer (1060) may include a portion whose upper surface height is different. That is, the metal layer (1060) may have different upper surface heights between a portion located above the opening (1059) and other portions. Furthermore, among the upper surfaces of the metal layer (1060), the portion located above the opening (1059) may be concave or convex, and the other portions may be relatively flat. According to the present embodiment, electrical connections may be made at the portions of the metal layer (1060) whose upper surfaces are flat.

[0128] Referring to FIGS. 3 and 4, the metal layer (1060) formed in the opening (1059) of the transparent layer (1070) is formed to cover the inner wall and bottom surface of the opening (1059). For example, when the metal layer (1060) is formed using a deposition technique, the metal layer (1060) may be formed to cover the inner wall and bottom surface along the opening (1059). Here, the bottom surface of the opening (1059) may be the upper surface of the metal layer (1060) that is positioned below the opening (1059) and is exposed to the outside.

[0129] For example, referring to FIG. 4, the 3-2 metal layer (1362) formed in the 3-2 opening (1352) of the 2nd transparent layer (1270) may be formed along the inner wall and bottom surface of the 3-2 opening (1352). Here, the bottom surface of the 3-2 opening (1352) is a portion of the upper surface of the 2-2 metal layer (1262) exposed by the 3-2 opening (1352).

[0130] Accordingly, a second-second metal layer (1262) and a third-second metal layer (1362) formed on top of the second-second metal layer (1262) may be laminated on top of the second insulating layer (1250) located at the bottom of the third-second opening (1352). Similarly, a first-second metal layer (1162) and a second-second metal layer (1262) may be laminated on top of the first insulating layer (1150) located at the bottom of the second-second opening (1252).

[0131] Also, referring to FIG. 3, a first-first metal layer (1161) and a second-first metal layer (1261) may be laminated on top of a first insulating layer (1150) located at the bottom of a second-first opening (1251). Also, a second-first metal layer (1261) and a third-first metal layer (1361) may be laminated on top of a second insulating layer (1250) located at the bottom of a third-third opening (1353). Also, a second-third metal layer (1263) and a third-third metal layer (1363) may be laminated on top of a second insulating layer (1250) located at the bottom of a third-fourth opening (1354).

[0132] In this way, according to the present embodiment, the metal layer (1060) located at the bottom and the metal layer (1060) located at the top are connected at the top of the insulating layer (1050). Therefore, when an opening (1059) is formed at the top of the insulating layer (1050), the metal layer (1060) can be formed in a two-layer structure at the top of the insulating layer (1050). In addition, one metal layer (1060) is formed at the opening (1059) located at the top of the insulating layer (1050).

[0133] Therefore, the thickness (W1) of the metal layer (1060) formed on the upper side of the insulating layer (1050) is thicker than the thickness (W2) of the metal layer (1060) formed on the inner side of the opening (1059). Here, the thickness of the metal layer (1060) formed on the upper side of the insulating layer (1050) is the length from the lower side to the upper side of the two-layer metal layer (1060). In addition, the thickness of the metal layer (1060) formed on the inner side of the opening (1059) is the length from the inner side of the opening (1059) to the inner side of the metal layer (1060).

[0134] Since the pixel element (1000) according to the present embodiment is formed so that the metal layer (1060) formed in the opening (1059) covers the upper surface of the metal layer (1060) located thereunder, the reliability of electrical connection can be improved.

[0135] However, the structure of the metal layer (1060) of the pixel element (1000) in the present embodiment is not limited thereto. For example, the metal layer (1060) of the pixel element (1000) may be formed in various structures, as illustrated in FIGS. 5 and 6.

[0136] FIGS. 5 to 39 are drawings for explaining a method for manufacturing a pixel element according to a first embodiment of the present invention.

[0137] Referring to FIGS. 5 to 13, first, the first to third light-emitting portions (1100, 1200, 1300) can be formed individually.

[0138] The first light emitting unit (1100) of FIG. 5, the second light emitting unit (1200) of FIG. 8, and the third light emitting unit (1300) of FIG. 11 can generate and emit light of different colors. For example, the first light emitting unit (1100) can generate and emit green light. The second light emitting unit (1200) can generate and emit blue light. Additionally, the third light emitting unit (1300) can generate and emit red light.

[0139] Additionally, the first to third light-emitting units (1100, 1200, 1300) can operate individually. Here, the operation is to generate and emit light.

[0140] Fig. 5 is a schematic plan view for explaining a first light-emitting portion (1100) of a pixel element (1000) according to a first embodiment of the present invention. In addition, Fig. 6 is a cross-sectional view (B1-B2) for explaining a first light-emitting portion (1100) of a pixel element (1000) according to a first embodiment of the present invention. In addition, Fig. 7 is another cross-sectional view (B3-B4) for explaining a first light-emitting portion (1100) of a pixel element (1000) according to a first embodiment of the present invention.

[0141] Referring to FIGS. 5 to 7, a first light-emitting portion (1100) may be formed on a first base (1110). The first light-emitting portion (1100) may include a first light-emitting structure (1120), a first ohmic electrode (1130), a first insulating layer (1150), and a first metal layer (1160).

[0142] According to the present embodiment, the first base (1110) may be a growth substrate capable of growing a semiconductor layer. For example, the first base (1110) may be formed of sapphire. However, the first base (1110) is not limited to being a growth substrate. The first base (1110) may also be formed of a light-transmitting material such as silicon, epoxy, or the like. For example, after the first light-emitting portion (1100) is formed on the growth substrate, the growth substrate may be removed, and the first light-emitting portion (1100) may be placed on the first base (1110), which is a light-transmitting material.

[0143] The first light-emitting structure (1120) may be formed on the first base (1110). The first light-emitting structure (1120) may be grown on the first base (1110) using metal-organic chemical vapor deposition (MOCVD) technology or molecular beam epitaxy (MBE) technology. The second light-emitting structure (1220) of the second light-emitting portion (1200) and the third light-emitting structure (1320) of the third light-emitting portion (1300), which will be described later, may also be formed in the same manner.

[0144] The first light-emitting structure (1120) may include a first-first semiconductor layer (1121), a first-second semiconductor layer (1123), and a first active layer (1122) formed between the first-first semiconductor layer (1121) and the first-second semiconductor layer (1123).

[0145] The semiconductor layer (1121) may be an n-type conductive semiconductor layer, and the first-second semiconductor layer (1123) may be a p-type conductive semiconductor layer. Or vice versa. In addition, the first light-emitting structure (1120) may generate and emit green light. That is, the first light-emitting unit (1100) may emit green light. For example, the first light-emitting structure (1120) may include a semiconductor material that emits green light, such as GaN, InGaN, GaP, AlGaInP, AlGaP, etc.

[0146] Referring to FIGS. 6 and 7, a portion of the first active layer (1122) and the 1-2 semiconductor layer (1123) may be etched to expose a portion of the upper surface of the 1-1 semiconductor layer (1121). At this time, the first active layer (1122) and the 1-2 semiconductor layer (1123) remaining on the 1-1 semiconductor layer (1121) after the etching process may become a first mesa structure (1140). Referring to FIG. 6, a plurality of first mesa structures (1140) may be provided.

[0147] Referring to FIGS. 6 and 7, the first mesa structure (1140) has a structure in which the side surface is vertical with respect to the upper surface of the 1-1 semiconductor layer (1121). However, the structure of the first mesa structure (1140) is not limited thereto. For example, the first mesa structure (1140) may have a structure in which the width and cross-sectional area become narrower from the 1-1 semiconductor layer (1121) to the 1-2 semiconductor layer (1123). That is, the first mesa structure (1140) may have a structure in which the side surface is inclined. Not only the first mesa structure (1140) of the first light-emitting portion (1100), but also the first mesa structures (1140) of the second light-emitting portion (1200) and the third light-emitting portion (1300) described below may be formed in a structure in which the side surface is vertical or inclined with respect to the upper surface of the 1-1 semiconductor layer (1121).

[0148] Referring to FIGS. 2 and 5, the first mesa structure (1140) of the first light-emitting portion (1100) may be formed to cover most of the upper surface of the first-first semiconductor layer (1121) except for the region where the first-first metal layer (1161) is formed and the surrounding region. Accordingly, the first mesa structure (1140) of the first light-emitting portion (1100) may be formed to surround the side surface of the first-first metal layer (1161) while being spaced apart from the first-first metal layer (1161). In addition, the first mesa structure (1140) of the first light-emitting portion (1100) may be formed such that the side surface is located on the inner side of the side surface of the first-first semiconductor layer (1121) and is spaced apart from the side surface of the first-first semiconductor layer (1121).

[0149] A first ohmic electrode (1130) may be formed on the upper portion of the semiconductor layer (1123). Furthermore, the first ohmic electrode (1130) may be formed to cover the upper surface of the first-second semiconductor layer (1123). The first ohmic electrode (1130) may be formed to cover a portion of the upper surface of the first-second semiconductor layer (1123). Alternatively, the first ohmic electrode (1130) may be formed to cover the entire upper surface of the first-second semiconductor layer (1123).

[0150] The first ohmic electrode (1130) may have high transmittance and high electrical conductivity for light emitted from the first light-emitting structure (1120). For example, the first ohmic electrode (1130) may be a transparent electrode. Furthermore, the first ohmic electrode (1130) may be ITO (Indium Tin Oxide). In the present embodiment, the first mesa structure (1140) may not only include the first active layer (1122) and the first-second semiconductor layer (1123), but may also include the first ohmic electrode (1130) positioned on the first-second semiconductor layer (1123).

[0151] The first insulating layer (1150) may be formed to cover the first light-emitting structure (1120) and the first ohmic electrode (1130). In addition, the first insulating layer (1150) may include a first-first opening (1151) and a first-second opening (1152).

[0152] The first-first opening (1151) of the first insulating layer (1150) is an opening (1059) that exposes the first-first semiconductor layer (1121). Therefore, the first-first opening (1151) can be positioned on the first-first semiconductor layer (1121) between the first mesa structures (1140).

[0153] The first-second opening (1152) of the first insulating layer (1150) is an opening (1059) that exposes the first ohmic electrode (1130). Therefore, the first-second opening (1152) may be located on the upper portion of the first mesa structure (1140). That is, the first-second opening (1152) may be located on the upper portion of the first ohmic electrode (1130) that covers the first-second semiconductor layer (1123).

[0154] The first insulating layer (1150) may be formed of a light-transmitting material. For example, the first insulating layer (1150) may be formed of a silicon oxide such as SiO2, a silicon nitride such as Si3N4, or a silicon oxynitride.

[0155] The first metal layer (1160) may be formed on top of the first insulating layer (1150). The first metal layer (1160) may be formed of a conductive material and may be electrically connected to the first light-emitting structure (1120). For example, the first metal layer (1160) may be formed of at least one metal. In addition, the first metal layer (1160) may be formed as a single layer or multiple layers.

[0156] The first metal layer (1160) may include a first-first metal layer (1161) and a first-second metal layer (1162).

[0157] The metal layer (1161) may be formed to fill the first-first opening (1151) of the first insulating layer (1150) between the first mesa structures (1140). In addition, the first-first metal layer (1161) may be formed to cover a portion of the first insulating layer (1150) around the first-first opening (1151). That is, the width and cross-sectional area of ​​the first-first metal layer (1161) may be larger than the diameter and cross-sectional area of ​​the first-first opening (1151) of the first insulating layer (1150).

[0158] The metal layer (1162) may be formed on the first mesa structure (1140) to fill the first-second openings of the first insulating layer (1150). In addition, the first-second metal layer (1162) may be formed to cover a portion of the first insulating layer (1150) around the first-second openings (1152). That is, the width and cross-sectional area of ​​the first-second metal layer (1162) may be larger than the diameter and cross-sectional area of ​​the first-second openings (1152) of the first insulating layer (1150).

[0159] In this way, the formed 1-1 metal layer (1161) can be electrically connected to the 1-1 semiconductor layer (1121) through the 1-1 opening (1151) of the 1-1 insulating layer (1150). In addition, the 1-2 metal layer (1162) can be electrically connected to the 1-2 ohmic electrode (1130) through the 1-2 opening (1152) of the 1-1 insulating layer (1150). Furthermore, the 1-2 metal layer (1162) can be electrically connected to the 1-2 semiconductor layer (1123) through the 1-1 ohmic electrode (1130).

[0160] Fig. 8 is a schematic plan view for explaining a second light-emitting portion (1200) of a pixel element (1000) according to a first embodiment of the present invention. In addition, Fig. 9 is a cross-sectional view (C1-C2) for explaining a second light-emitting portion (1200) of a pixel element (1000) according to a first embodiment of the present invention. In addition, Fig. 10 is another cross-sectional view (C3-C4) for explaining a second light-emitting portion (1200) of a pixel element (1000) according to a first embodiment of the present invention.

[0161] Referring to FIGS. 8 to 10, a second light-emitting portion (1200) may be formed on a second base (1210). The second light-emitting portion (1200) may include a second light-emitting structure (1220), a second ohmic electrode (1230), and a second insulating layer (1250).

[0162] According to the present embodiment, the second base (1210) may be a growth substrate capable of growing a semiconductor layer. For example, the second base (1210) may be formed of sapphire.

[0163] A second light-emitting structure (1220) may be formed on top of a second base (1210). The second light-emitting structure (1220) may include a second-first semiconductor layer (1221), a second-second semiconductor layer (1223), and a second active layer (1222) formed between the second-first semiconductor layer (1221) and the second-second semiconductor layer (1223). The second light-emitting structure (1220) may be formed in the same manner as the first light-emitting structure (1120).

[0164] The second-first semiconductor layer (1221) may be an n-type conductive semiconductor layer, and the second-second semiconductor layer (1223) may be a p-type conductive semiconductor layer. Or vice versa. The second light-emitting structure (1220) may generate and emit blue light. Accordingly, the second light-emitting unit (1200) may also emit blue light. For example, the second light-emitting structure (1220) may include a semiconductor material that emits blue light, such as GaN, InGaN, ZnSe, or the like.

[0165] Referring to FIGS. 9 and 10, a portion of the second active layer (1222) and the 2-2 semiconductor layer (1223) may be etched to expose a portion of the upper surface of the 2-1 semiconductor layer (1221). At this time, the second active layer (1222) and the 2-2 semiconductor layer (1223) remaining on the upper portion of the 2-1 semiconductor layer (1221) after the etching process may become a second mesa structure (1240). The second light-emitting portion (1200) may include a plurality of such second mesa structures (1240).

[0166] A second ohmic electrode (1230) may be formed on the upper portion of the second-second semiconductor layer (1223). Furthermore, the second ohmic electrode (1230) may be formed to cover the upper surface of the second-second semiconductor layer (1223). The second ohmic electrode (1230) may be formed to cover part or the entire upper surface of the second-second semiconductor layer (1223).

[0167] Referring to FIG. 2 and FIG. 8, the second-first semiconductor layer (1221) of the second light-emitting portion (1200) can be formed so as not to overlap with the openings (1059) of the first light-emitting portion (1100) when the second light-emitting portion (1200) is later laminated on top of the first light-emitting portion (1100).

[0168] In addition, the second mesa structure (1240) of the second light-emitting portion (1200) may be formed so as not to overlap with the first metal layer (1160) when the second light-emitting portion (1200) is later laminated on top of the first light-emitting portion (1100). Accordingly, the second mesa structure (1240) may be formed in an area excluding an area where the first-first metal layer (1161) and the first-second metal layer (1162) are positioned below, as illustrated in FIGS. 2 and 8.

[0169] The ohmic electrode (1230) may have high transmittance and high electrical conductivity for light emitted from the second light-emitting structure (1220). For example, the second ohmic electrode (1230) may be a transparent electrode. Furthermore, the second ohmic electrode (1230) may be ITO (Indium Tin Oxide). The second mesa structure (1240) of the second light-emitting portion (1200) may also include the second ohmic electrode (1230) formed on the upper portion of the second-2 semiconductor layer (1223).

[0170] The insulating layer (1250) may be formed to cover the second light-emitting structure (1220) and the second ohmic electrode (1230). Additionally, the second insulating layer (1250) may be formed to cover the upper surface of the second base (1210) located between the mesas.

[0171] The insulating layer (1250) may be formed of a light-transmitting material. For example, the second insulating layer (1250) may be formed of silicon oxide such as SiO2, silicon nitride such as Si3N4, or silicon oxynitride.

[0172] Fig. 11 is a schematic plan view for explaining a third light-emitting portion (1300) of a pixel element (1000) according to a first embodiment of the present invention. In addition, Fig. 12 is a cross-sectional view (D1-D2) for explaining a third light-emitting portion (1300) of a pixel element (1000) according to a first embodiment of the present invention. In addition, Fig. 13 is another cross-sectional view (D3-D4) for explaining a third light-emitting portion (1300) of a pixel element (1000) according to a first embodiment of the present invention.

[0173] Referring to FIGS. 11 to 13, a third light-emitting portion (1300) may be formed on the upper portion of the third base (1310). The third light-emitting portion (1300) may include a third light-emitting structure (1320), a third ohmic electrode (1330), and a third insulating layer (1350).

[0174] According to the present embodiment, the third base (1310) may be a growth substrate capable of growing a semiconductor layer. For example, the third base (1310) may be formed of sapphire.

[0175] A third light-emitting structure (1320) may be formed on top of a third base (1310). The third light-emitting structure (1320) may include a third-first semiconductor layer (1321), a third-second semiconductor layer (1323), and a third active layer (1322) formed between the third-first semiconductor layer (1321) and the third-second semiconductor layer (1323). The third light-emitting structure (1320) may be formed in the same manner as the first light-emitting structure (1120).

[0176] The third-first semiconductor layer (1321) may be an n-type conductive semiconductor layer, and the third-second semiconductor layer (1323) may be a p-type conductive semiconductor layer. Or vice versa. The third light-emitting structure (1320) may generate and emit red light. Accordingly, the third light-emitting unit (1300) may also emit red light. For example, the third light-emitting structure (1320) may include a semiconductor material that emits red light, such as AlGaAs, GaAsP, AlGaInP, or GaP.

[0177] Referring to FIG. 2 and FIG. 11, the 3-1 semiconductor layer (1321) of the third light-emitting portion (1300) can be formed so as not to overlap with the openings (1059) of the first light-emitting portion (1100) and the second light-emitting portion (1200) when the third light-emitting portion (1300) is later laminated on top of the second light-emitting portion (1200).

[0178] Additionally, the third mesa structure (1340) of the third light-emitting portion (1300) may be formed so as not to overlap with the first metal layer (1160) of the first light-emitting portion (1100) and the second metal layer (1260) of the second light-emitting portion (1200).

[0179] Referring to FIGS. 12 and 13, a portion of the third active layer (1322) and the third-second semiconductor layer (1323) may be etched to expose a portion of the upper surface of the third-first semiconductor layer (1321). At this time, the third active layer (1322) and the third-second semiconductor layer (1323) remaining on the upper portion of the third-first semiconductor layer (1321) after the etching process may become a third mesa structure (1340). Referring to FIG. 12, the third light-emitting portion (1300) may include a plurality of third mesa structures (1340).

[0180] A third ohmic electrode (1330) may be formed on the upper portion of the third-2 semiconductor layer (1323). Furthermore, the third ohmic electrode (1330) may be formed to cover the upper surface of the third-2 semiconductor layer (1323). The third ohmic electrode (1330) may be formed to cover part or the entire upper surface of the third-2 semiconductor layer (1323).

[0181] The third ohmic electrode (1330) may have high electrical conductivity to light emitted from the third light-emitting structure (1320). For example, the third ohmic electrode (1330) may be formed of a metal. In addition, the ohmic electrode (1330) may have high light transmittance. For example, the third ohmic electrode (1330) may be a transparent electrode. Furthermore, the third ohmic electrode (1330) may be ITO (Indium Tin Oxide).

[0182] The third insulating layer (1350) may be formed to cover the third light-emitting structure (1320) and the third ohmic electrode (1330). Additionally, the third insulating layer (1350) may be formed to cover the upper surface of the third base (1310) located between the mesas.

[0183] The third insulating layer (1350) may be formed of a light-transmitting material. For example, the third insulating layer (1350) may be formed of a silicon oxide such as SiO2, a silicon nitride such as Si3N4, or a silicon oxynitride.

[0184] Referring to FIGS. 14 to 26, a second light emitting portion (1200) can be laminated on top of a first light emitting portion (1100).

[0185] Referring to FIGS. 14 and 15, a first transparent layer (1170) can be formed on the first light-emitting portion (1100).

[0186] The first transparent layer (1170) may be formed to cover the first light-emitting portion (1100) on top of the first base (1110). At this time, the first transparent layer (1170) may be formed to have a flat upper surface.

[0187] The first transparent layer (1170) may be formed of an insulating, light-transmitting material. For example, the first transparent layer (1170) may be formed of the same material as the first insulating layer (1150).

[0188] In the present embodiment, the first transparent layer (1170) is formed separately after the first light-emitting portion (1100) is formed, but this is not limited thereto. That is, the first transparent layer (1170) may be included in the first light-emitting portion (1100).

[0189] Referring to FIGS. 16 and 17, a first support substrate (1411) may be attached to an upper portion of a second light-emitting portion (1200). The first support substrate (1411) may be any material capable of supporting the second light-emitting portion (1200) until the second light-emitting portion (1200) is laminated onto the first light-emitting portion (1100). That is, the second light-emitting portion (1200) may be laminated onto the first light-emitting portion (1100) while being attached to the first support substrate (1411). For example, the first support substrate (1411) may be, but is not limited to, a sapphire substrate or a glass substrate.

[0190] Additionally, the second light emitting unit (1200) can be attached to the first support substrate (1411) using an adhesive tape (1511). The adhesive tape (1511) can be made of a material whose adhesive strength is reduced by heat or ultraviolet rays.

[0191] Referring to FIGS. 18 and 19, the second base (1210) located at the bottom of the second light-emitting portion (1200) is removed. For example, the second base (1210) can be removed using a laser lift-off technique, a chemical lift-off technique, or a wet etching technique.

[0192] Referring to FIGS. 20 and 21, a second light-emitting portion (1200) can be laminated on a first light-emitting portion (1100). The second light-emitting portion (1200) can be laminated on the first transparent layer (1170) of the first light-emitting portion (1100). Accordingly, the second-first semiconductor layer (1221) of the second light-emitting portion (1200) can be positioned on the first transparent layer (1170) of the first light-emitting portion (1100).

[0193] After laminating the second light-emitting portion (1200) on the first light-emitting portion (1100), the first support substrate (1411) is removed. For example, the first support substrate (1411) can be detached from the second light-emitting portion (1200) by weakening the adhesive strength of the adhesive tape (1511) using heat, ultraviolet rays, or infrared rays.

[0194] Referring to FIGS. 22 and 23, the second insulating layer (1250) and the first transparent layer (1170) can be patterned. A second opening (1259) can be formed in the second insulating layer (1250) and the first transparent layer (1170). The second opening (1259) can include the 2-1 opening to the 2-4 opening (1251, 1252, 1253, 1254).

[0195] Referring to FIG. 22, the 2-1 opening (1251) may be formed on the upper portion of the 1-1 metal layer (1161). That is, the 2-1 opening (1251) may be formed in the second insulating layer (1250) and the first transparent layer (1170) covering the 1-1 metal layer (1161), thereby exposing a portion of the 1-1 metal layer (1161) to the outside.

[0196] The 2-3 opening (1253) is formed in the second insulating layer (1250) covering the 2-1 semiconductor layer (1221), so that a part of the 2-1 semiconductor layer (1221) can be exposed to the outside. At this time, the 2-3 opening (1253) can be formed around the 1-1 metal layer (1161) and the 2-1 opening (1251).

[0197] The 2-4 opening (1254) is formed in the second insulating layer (1250) covering the 2-2 semiconductor layer (1223), so that a part of the 2-2 semiconductor layer (1223) can be exposed to the outside.

[0198] Referring to FIG. 23, the 2-2 opening (1252) may be formed on the upper portion of the 1-2 metal layer (1162). That is, the 2-2 opening (1252) may be formed in the second insulating layer (1250) and the first transparent layer (1170) covering the 1-2 metal layer (1162), thereby exposing a portion of the 1-2 metal layer (1162) to the outside.

[0199] In this way, the second opening (1259) of the present embodiment can be formed by patterning the second insulating layer (1250) or the second insulating layer (1250) and the first transparent layer (1170). Since the second insulating layer (1250) and the first transparent layer (1170) are formed of the same material, a plurality of second openings (1259) can be formed simultaneously through the same process. For example, the second openings (1259) can be formed by a dry etching technique such as plasma etching or laser etching.

[0200] According to the present embodiment, only the second insulating layer (1250) or the second insulating layer (1250) and the first transparent layer (1170) are formed on the upper portions of the first metal layer (1160), the second-first semiconductor layer (1221) of the second light-emitting portion (1200), and the second ohmic electrode (1230). Therefore, the second openings (1259) exposing the first metal layer (1160), the second-first semiconductor layer (1221), and the second ohmic electrode (1230) can be formed simultaneously in just one process.

[0201] If a material other than the first insulating layer (1150) and the first transparent layer (1170), such as a metal layer (1060), is formed on top of the first metal layer (1160), the second-first semiconductor layer (1221), and the second ohmic electrode (1230), it is difficult to simultaneously remove multiple layers made of different materials. Therefore, in this case, each layer must be individually removed to form an opening (1059).

[0202] However, since the pixel element (1000) according to the embodiment of the present invention has only a layer made of the same material on the upper portions of the first metal layer (1160), the second-first semiconductor layer (1221) of the second light-emitting portion (1200), and the second ohmic electrode (1230), the second openings (1259) can be formed simultaneously with only one process. Accordingly, the process is simplified, and the time and cost required for the process can be saved.

[0203] Referring to FIGS. 24 to 26, a second metal layer (1260) can be formed.

[0204] Fig. 24 is a plan view of a laminate of a first light-emitting portion (1100) and a second light-emitting portion (1200) on which a second metal layer (1260) is formed. Fig. 25 is a cross-sectional view (E1-E2) of Fig. 24. In addition, Fig. 26 is another cross-sectional view (E3-E4) of Fig. 24.

[0205] The second metal layer (1260) may include a second-first metal layer (1261), a second-second metal layer (1262), and a second-third metal layer (1263).

[0206] Referring to FIG. 25, the 2-1 metal layer (1261) can be formed to simultaneously fill the 2-1 opening (1251) and the 2-3 opening (1253). The 2-1 metal layer (1261) can be in contact with the 1-1 metal layer (1161) through the 2-1 opening (1251) and be electrically connected to each other. In addition, the 2-1 metal layer (1261) can be electrically connected to the 2-1 semiconductor layer (1221) of the second light-emitting portion (1200) through the 2-3 opening (1253).

[0207] In addition, the 2-1 metal layer (1261) may be formed to cover the upper surface of the second insulating layer (1250) around the 2-1 opening (1251). In addition, the 2-1 metal layer (1261) may be formed to cover the upper surface of the second insulating layer around the 2-3 opening (1253). That is, the 2-1 metal layer (1261) may be formed to fill not only the 2-1 opening (1251) and the 2-3 opening (1253), but also to cover the surrounding area thereof.

[0208] Additionally, the 2-1 metal layer (1261) may be formed to extend along the 2nd insulating layer (1250) from the upper portion of the 1-1 metal layer (1161) to the upper portion of the 2-1 semiconductor layer (1221) of the second light-emitting portion (1200).

[0209] In this way, a part of the 2-1 metal layer (1261) is connected to the 1-1 metal layer (1161), and another part is electrically connected to the 2-1 semiconductor layer (1221) of the second light-emitting portion (1200). Therefore, the 1-1 semiconductor layer (1121) of the first light-emitting portion (1100) and the 1-1 semiconductor layer (1121) of the second light-emitting portion (1200) can be electrically connected to each other through the 2-1 metal layer (1261).

[0210] The 2-3 metal layer (1263) may be formed to fill the 2-4 opening (1254). Therefore, the 2-3 metal layer (1263) may be electrically connected to the second ohmic electrode (1230) through the 2-4 opening (1254). In addition, the 2-3 metal layer (1263) may be electrically connected to the 2-2 semiconductor layer (1223) of the second light-emitting portion (1200) by being connected to the second ohmic electrode (1230). At this time, the 2-3 metal layer (1263) may be formed to cover the upper surface of the second insulating layer (1250) around the 2-4 opening (1254). Therefore, the width and cross-sectional area of ​​the 2-3 metal layer (1263) are larger than the width and cross-sectional area of ​​the 2-4 opening (1254).

[0211] Referring to FIG. 26, the second-second metal layer (1262) may be formed to partially fill the second-second opening (1252). Accordingly, the second-second metal layer (1262) may be electrically connected to the first-second metal layer (1162) through the second-second opening (1252). At this time, the second-second metal layer (1262) may be formed to further cover the insulating layer (1050) around the second-second opening (1252). In addition, another portion of the second-second metal layer (1262) may be formed on top of the second light-emitting portion (1200). More specifically, another portion of the second-second metal layer (1262) may be formed to cover a portion of the second insulating layer (1250) on top of the second ohmic electrode (1230).

[0212] Additionally, the second-second metal layer (1262) may be formed to extend along the second insulating layer (1250) from the upper portion of the first-second metal layer (1162) to the upper portion of the second ohmic electrode (1230).

[0213] According to an embodiment of the present invention, the second metal layer (1260) can be formed using a plating or deposition technique.

[0214] In addition, the 2-1 opening (1251) may be formed on the outside of the 1-1 opening (1151). Accordingly, the 2-1 metal layer (1261) may be formed to contact the upper surface of the 1-1 metal layer (1161) located on the outside of the 1-1 opening (1151). That is, the 2-1 metal layer (1261) may be formed on the flat upper surface of the 1-1 metal layer (1161) located on the outside of the 1-1 opening (1151).

[0215] When the first-first metal layer (1161) is formed, the upper surface of the first-first metal layer (1161) filling the first-first opening (1151) may not be flat compared to other portions due to the step difference between the first insulating layer (1150) and the first-first opening (1151). For example, the upper surface of the first-first metal layer (1161) located above the first-first opening (1151) may be concave. Or, if the first-first metal layer (1161) is excessively filled in the first-first opening (1151) or is not able to fill the inside of the first-first opening (1151) due to the narrow width of the first-first opening (1151) and is only laminated on the upper side, the upper surface of the first-first metal layer (1161) located on the upper side of the first-first opening (1151) may be convex. In this way, the upper surface of the first-first metal layer (1161) located on the upper side of the first-first opening (1151) may be concave or convex and may not be flat for various reasons. In this way, if the second metal layer (1260) is formed on the unflat part, the performance of the electrical connection between the first-first metal layer (1161) and the second-first metal layer (1261) may be different for each product. For example, the bonding area between the first-first metal layer (1161) and the second-first metal layer (1261) may vary from product to product. Alternatively, the bonding between the first-first metal layer (1161) and the second-first metal layer (1261) may be unstable. In other words, it is difficult for all products to maintain the same level of quality.

[0216] However, in the pixel element (1000) according to the first embodiment of the present invention, the 2-1 metal layer (1261) is formed on a flat portion of the 1-1 metal layer (1161) located on the first insulating layer (1150). Therefore, stable bonding between the 1-1 metal layer (1161) and the 2-1 metal layer (1261) is possible, so that products having the same level of quality can be mass-produced. In addition, not only the 2-1 metal layer (1261), but also all of the 2nd metal layers (1260) connected to the 1st metal layer (1160) can be formed on the flat upper surface of the 1st metal layer (1160).

[0217] Referring to FIGS. 27 to 39, a third light-emitting portion (1300) can be laminated on top of a second light-emitting portion (1200).

[0218] Referring to FIGS. 27 and 28, a second transparent layer (1270) may be formed on top of a first transparent layer (1170). The second transparent layer (1270) may be formed to cover the second light-emitting portion (1200) and the second metal layer (1260) from above the first transparent layer (1170). At this time, the second transparent layer (1270) may be formed to have a flat upper surface.

[0219] The second transparent layer (1270) may be formed of an insulating, light-transmitting material. For example, the second transparent layer (1270) may be formed of polyimide (PI) or epoxy molding compound (EMC). Alternatively, the second transparent layer (1270) may be formed of the same material as the second insulating layer (1250).

[0220] Referring to FIGS. 29 and 30, a second support substrate (1412) may be attached to the upper portion of the third light-emitting portion (1300). The third light-emitting portion (1300) may be laminated on the second light-emitting portion (1200) while being attached to the second support substrate (1412). For example, the second support substrate (1412) may be a sapphire substrate or a glass substrate, but is not limited thereto. That is, the second support substrate (1412) may be any material that can support the third light-emitting portion (1300) until the third light-emitting portion (1300) is laminated on the second light-emitting portion (1200).

[0221] Additionally, the third light-emitting unit (1300) can be attached to the second support substrate (1412) using an adhesive tape (1511). The adhesive tape (1511) can be made of a material whose adhesive strength is reduced by heat or ultraviolet rays.

[0222] Referring to FIGS. 31 and 32, the third base (1310) located at the bottom of the third light-emitting portion (1300) is removed. For example, the third base (1310) can be removed using a laser lift-off technique, a chemical lift-off technique, or a wet etching technique.

[0223] Referring to FIGS. 33 and 34, a third light-emitting portion (1300) can be laminated on a second light-emitting portion (1200). The third light-emitting portion (1300) can be laminated on the second transparent layer (1270) of the second light-emitting portion (1200). Accordingly, the 3-1 semiconductor layer (1321) of the third light-emitting portion (1300) can be positioned on the second transparent layer (1270) of the second light-emitting portion (1200).

[0224] After the third light-emitting portion (1300) is laminated on the second light-emitting portion (1200), the second support substrate (1412) is removed. For example, the second support substrate (1412) can be detached from the third light-emitting portion (1300) by weakening the adhesive strength of the adhesive tape (1511) using heat, ultraviolet rays, or infrared rays.

[0225] Referring to FIGS. 35 and 36, the third insulating layer (1350) and the second transparent layer (1270) of the third light-emitting portion (1300) can be patterned. A third opening (1359) can be formed in the third insulating layer (1350) and the second transparent layer (1270). The third opening (1359) can include the 3-1 opening to the 3-5 opening (1351, 1352, 1353, 1354, 1355).

[0226] Referring to FIG. 35, the 3-1 opening (1351) may be formed on the upper portion of the 2-1 metal layer (1261). At this time, the 3-1 opening (1351) may be formed to expose the 2-1 metal layer (1261) located on the upper portion of the 2-1 semiconductor layer (1221) of the second light-emitting portion (1200).

[0227] The 3-3 opening (1353) may be formed in the third insulating layer (1350) covering the 3-1 semiconductor layer (1321) of the third light-emitting portion (1300), so as to expose a portion of the 3-1 semiconductor layer (1321) to the outside. At this time, the 3-3 opening (1353) may be formed at a position adjacent to the 3-1 opening (1351).

[0228] The 3rd-4th opening (1354) is formed in the second transparent layer (1270) and the third insulating layer (1350) formed on the upper part of the 2nd-3rd metal layer (1263) of the 2nd light-emitting portion (1200). Therefore, the 3rd-4th opening (1354) can expose a part of the 2nd-3rd metal layer (1263) to the outside.

[0229] Referring to FIG. 36, the 3-2 opening (1352) may be formed on the upper portion of the 2-2 metal layer (1262). That is, the 3-2 opening (1352) may be formed in the third insulating layer (1350) and the second transparent layer (1270) covering the 2-2 metal layer (1262), thereby exposing a portion of the 2-2 metal layer (1262) to the outside.

[0230] The third-fifth opening (1355) may be formed in the third insulating layer (1350) covering the upper surface of the third ohmic electrode (1330) of the third light-emitting portion (1300). Accordingly, the third-fifth opening (1355) may be formed to be positioned on the upper portion of the third ohmic electrode (1330) and expose a portion of the third ohmic electrode (1330).

[0231] For example, the third opening (1359) can be formed by a dry etching technique such as plasma etching or laser etching.

[0232] According to the present embodiment, a third insulating layer (1350) is formed on the upper portion of the second metal layer (1260) where the third opening (1359) is to be formed, on the upper portion of the third-first semiconductor layer (1321), and on the upper portion of the third transparent layer (1070), or the third insulating layer (1350) and the second transparent layer (1270) are formed. That is, the third opening (1359) can be formed in a layer made of the same material. Therefore, similar to the second opening (1259), the process applied when forming the opening (1059) can be simplified, thereby saving cost and time.

[0233] Referring to FIGS. 37 to 39, a third metal layer (1360) can be formed.

[0234] Fig. 37 is a schematic plan view of a pixel element (1000) having a third metal layer (1360) formed thereon. Fig. 37 is a cross-sectional view (F1-F2) of a pixel element (1000) having a third metal layer (1360) formed thereon. In addition, Fig. 38 is another cross-sectional view (F3-F4) of a pixel element (1000) having a third metal layer (1360) formed thereon.

[0235] The third metal layer (1360) may include the 3-1 metal layer to the 3-4 metal layer (1361, 1362, 1363, 1364).

[0236] Referring to FIG. 38, the 3-1 metal layer (1361) can be formed to simultaneously fill the 3-1 opening (1351) and the 3-3 opening (1353). The 3-1 metal layer (1361) can be in contact with the 2-1 metal layer (1261) through the 3-1 opening (1351) and be electrically connected to each other. In addition, the 3-1 metal layer (1361) can be electrically connected to the 3-1 semiconductor layer (1321) of the 3rd light-emitting portion (1300) through the 3-3 opening (1353).

[0237] In addition, the 3-1 metal layer (1361) may be formed to cover the upper surface of the 3rd insulating layer (1350) around the 3-1 opening (1351). In addition, the 3-1 metal layer (1361) may be formed to cover the upper surface of the 3rd insulating layer (1350) around the 3-3 opening (1353). That is, the 3-1 metal layer (1361) may be formed to fill not only the 3-1 opening (1351) and the 3-3 opening (1353), but also cover the surrounding area thereof.

[0238] Additionally, the 3-1 metal layer (1361) may be formed to extend along the 3rd insulating layer (1350) from the upper portion of the 2-1 metal layer (1261) to the upper portion of the 3-1 semiconductor layer (1321) of the 3rd light-emitting portion (1300).

[0239] In this embodiment, the third metal layer (1360) in contact with the second metal layer (1260) can be formed on a flat upper surface of the second metal layer (1260).

[0240] In this way, a part of the 3-1 metal layer (1361) is connected to the 2-1 metal layer (1261), and another part is electrically connected to the 3-1 semiconductor layer (1321) of the 3rd light-emitting part (1300). Therefore, the 2-1 semiconductor layer (1221) of the 2nd light-emitting part (1200) and the 2-1 semiconductor layer (1221) of the 3rd light-emitting part (1300) can be electrically connected to each other through the 3-1 metal layer (1361).

[0241] In the pixel element (1000) of the present embodiment, a first-first metal layer (1161), a second-first metal layer (1261), and a third-first metal layer (1361) are electrically connected to each other. In addition, the first-first metal layer (1161) is electrically connected to the first-first semiconductor layer (1121) of the first light-emitting portion (1100), the second-first metal layer (1261) is electrically connected to the second-first semiconductor layer (1221) of the second light-emitting portion (1200), and the third-first metal layer (1361) is electrically connected to the third-first semiconductor layer (1321) of the third light-emitting portion (1300). Accordingly, in the present embodiment, the pixel element (1000) may be electrically connected to the 1-1 semiconductor layer (1121) of the first light-emitting portion (1100), the 2-1 semiconductor layer (1221) of the second light-emitting portion (1200), and the 3-1 semiconductor layer (1321) of the third light-emitting portion (1300).

[0242] Accordingly, the 1-1 metal layer (1161), the 2-1 metal layer (1261), and the 3-1 metal layer (1361) can be a common electrode that electrically connects the first light-emitting part (1100), the second light-emitting part (1200), and the third light-emitting part (1300) simultaneously.

[0243] In addition, a portion of the 3-1 metal layer (1361) formed on the upper portion of the 3rd ohmic electrode (1330) and exposed to the outside of the pixel element (1000) can become a pad of a common electrode. That is, the 3-1 metal layer (1361) becomes a common electrode pad, and an external electric signal can be simultaneously applied to the 1-1 semiconductor layer (1121), the 2-1 semiconductor layer (1221), and the 3-1 semiconductor layer (1321) of the first to third light-emitting units (1100, 1200, 1300) through the 3-1 metal layer (1361).

[0244] The 3-3 metal layer (1363) can be formed to fill the 3-4 opening (1354). Accordingly, the 3-3 metal layer (1363) can be electrically connected to the 2-3 metal layer (1263) through the 3-4 opening (1354).

[0245] The 3-3 metal layer (1363) may be formed to cover the upper surface of the 3rd insulating layer (1350) around the 3-4 opening (1354). In addition, the 3-3 metal layer (1363) may be formed to extend from the upper surface of the 2-3 metal layer (1263) to the upper surface of the 3rd ohmic electrode (1330).

[0246] In the pixel element (1000) of the present embodiment, the 2-3 metal layer (1263) and the 3-3 metal layer (1363) are electrically connected to each other. In addition, the 2-3 metal layer (1263) is connected to the second ohmic electrode (1230) of the second light-emitting portion (1200). Therefore, the 3-3 metal layer (1363) is electrically connected to the 2-2 semiconductor layer (1223) of the second light-emitting portion (1200), which is electrically connected to the second ohmic electrode (1230). Here, the 2-3 metal layer (1263) and the 3-3 metal layer (1363) that are electrically connected together to the 2-2 semiconductor layer (1223) can serve as a second electrode.

[0247] At this time, a portion of the 3-3 metal layer (1363) formed on the upper portion of the 3rd ohmic electrode (1330) and exposed to the outside of the pixel element (1000) may be a second electrode pad connected to the second light-emitting unit (1200). That is, an external electric signal may be applied to the 2-2 semiconductor layer (1223) of the second light-emitting unit (1200) through the 3-3 metal layer (1363), which is the second electrode pad. According to the present embodiment, when an electric signal is applied to the 3-3 metal layer (1363), which is the second electrode pad, the second light-emitting unit (1200) may emit blue light.

[0248] Referring to FIG. 39, the 3-2 metal layer (1362) is formed so as to partially fill the 3-2 opening (1352). Therefore, the 3-2 metal layer (1362) can be electrically connected to the 2-2 metal layer (1262) through the 3-2 opening (1352). At this time, the 2-2 metal layer (1262) is electrically connected to the 1-2 metal layer (1162). Consequently, the 3-2 metal layer (1362) can be electrically connected to the 1-2 semiconductor layer (1123) of the first light-emitting portion (1100). Here, the first-second metal layer (1162), the second-second metal layer (1262), and the third-second metal layer (1362) electrically connected with the first-second semiconductor layer (1123) of the first light-emitting portion (1100) can be the first electrode.

[0249] In addition, a portion of the 3-2 metal layer (1362) formed on the upper portion of the 3rd ohmic electrode (1330) and exposed to the outside of the pixel element (1000) may be a first electrode pad connected to the first light-emitting unit (1100). That is, an external electric signal may be applied to the 1-2 semiconductor layer (1123) of the first light-emitting unit (1100) through the 3-2 metal layer (1362), which is the first electrode pad. According to the present embodiment, when an electric signal is applied to the 3-2 metal layer (1362), which is the first electrode pad, the first light-emitting unit (1100) may emit green light.

[0250] Additionally, the 3-2 metal layer (1362) may be formed to further cover the insulating layer (1050) around the 3-2 opening (1352). Additionally, another portion of the 3-2 metal layer (1362) may be formed on top of the third light-emitting portion (1300). More specifically, another portion of the 3-2 metal layer (1362) may be formed to cover a portion of the third insulating layer (1350) on top of the third ohmic electrode (1330).

[0251] Additionally, the 3-2 metal layer (1362) may be formed to extend along the 3rd insulating layer (1350) from the upper portion of the 2-2 metal layer (1262) to the upper portion of the 3rd ohmic electrode (1330).

[0252] The 3-4 metal layer (1364) may be formed to fill the 3-5 opening (1355) of the 3rd insulating layer (1350). Accordingly, the 3-4 metal layer (1364) may be in contact with the 3rd ohmic electrode (1330) through the 3-5 opening (1355). Accordingly, the 3-4 metal layer (1364) may be electrically connected to the 3-2 semiconductor layer (1323) of the 3rd light-emitting portion (1300) through the 3rd ohmic electrode (1330) with which it is in contact. In addition, the 3-4 metal layer (1364) may be formed to further cover the 3rd insulating layer (1350) around the 3-5 opening (1355). Therefore, the width and cross-sectional area of ​​the 3-4th metal layer (1364) are larger than the width and cross-sectional area of ​​the 3-5th opening (1355).

[0253] The 3rd-4th metal layer (1364) exposed to the outside of the pixel element (1000) can be a third electrode pad connected to the second light-emitting unit (1200). That is, an external electrical signal can be applied to the 3rd-2nd semiconductor layer (1323) of the third light-emitting unit (1300) through the 3rd-4th metal layer (1364), which is the third electrode pad. According to the present embodiment, when an electrical signal is applied to the 3rd-4th metal layer (1364), which is the third electrode pad, the 3rd light-emitting unit (1300) can emit red light.

[0254] Referring to FIG. 38, the first-first opening (1151) located on the first-first semiconductor layer (1121), the second-third opening (1253) located on the second-first semiconductor layer (1221), and the third-third opening (1353) located on the third-first semiconductor layer (1321) are all located at different locations. In addition, the center line of the second-third opening (1253) is located between the center line of the first-first opening (1151) and the center line of the third-third opening (1353).

[0255] Additionally, one side of the 2-1 semiconductor layer (1221) and the 3-1 semiconductor layer (1321) are positioned on the upper side of the 1-1 semiconductor layer (1121). At this time, one side of the 2-1 semiconductor layer (1221) is positioned between the 1-1 opening (1151) and one side of the 3-1 semiconductor layer (1321).

[0256] Accordingly, the first-first metal layer (1161), the second-first metal layer (1261), and the third-first metal layer (1361), which are common electrodes that fill these openings (1059) and are electrically connected to each other, can be formed so that their centers are positioned on different vertical and horizontal lines to form a step structure.

[0257] In addition, the 2nd-3rd metal layer (1263) and the 3rd-3rd metal layer (1363), which are electrically connected to each other, have their centers positioned on different vertical and horizontal lines. Accordingly, the 2nd-3rd metal layer (1263) and the 3rd-3rd metal layer (1363), which are the second electrodes, can also be formed to form a step structure.

[0258] Referring to Fig. 39, the first-second metal layer (1162), the second-second metal layer (1262), and the third-second metal layer (1362), which are electrically connected to each other, have their centers positioned on different vertical and horizontal lines. Accordingly, the first electrode can also be formed to form a step structure.

[0259] Conventionally, the first to third light-emitting portions are formed so that their cross-sectional areas decrease as they move away from the first base, and the electrodes are formed along the outer sides of the first to third light-emitting portions. In this case, although the electrodes are not formed on the inner sides of the first to third light-emitting portions, the light-emitting areas of the first to third light-emitting portions are different from each other. Accordingly, the pixel elements have different light quantities for each color.

[0260] According to the first embodiment of the present invention, the pixel element (1000) can be formed so that the area of ​​the first mesa structure (1140) of the first light-emitting portion (1100) of FIG. 5, the area of ​​the second mesa structure (1240) of the second light-emitting portion (1200) of FIG. 8, and the area of ​​the third mesa structure (1340) of the third light-emitting portion (1300) of FIG. 11 are as similar as possible to each other. That is, the pixel element (1000) according to the first embodiment of the present invention can be formed so that the light-emitting surfaces of the first light-emitting portion (1100), the second light-emitting portion (1200), and the third light-emitting portion (1300) have the maximum area excluding the metal layer (1060) located at the bottom of each light-emitting portion, so that the difference in the area of ​​the light-emitting surfaces of each light-emitting portion is minimized. Therefore, light of similar amounts can be emitted from the first light emitting unit (1100), the second light emitting unit (1200), and the third light emitting unit (1300).

[0261] In addition, conventionally, holes are formed in the first to third light-emitting structures to bring the first metal layer and the third metal layer into contact with the first and third light-emitting portions, and are not filled with a conductive material. That is, electrodes are formed on the inside of the first to third light-emitting portions. In this case, the light-emitting area of ​​the first to third light-emitting portions is reduced by the electrodes formed on the inside.

[0262] However, the pixel element (1000) according to an embodiment of the present invention can prevent the light emitting area of ​​the first to third light emitting parts (1100, 1200, 1300) from being reduced by the electrodes, thereby preventing loss of brightness due to a reduction in the light emitting area.

[0263] Additionally, conventionally, after all of the first to third light-emitting units were laminated, a metal layer for electrical connection with each light-emitting unit was formed. Therefore, the openings formed for electrical connection between the metal layer and each light-emitting unit had to be formed in layers made of different materials.

[0264] The pixel element (1000) according to an embodiment of the present invention forms openings (1059) on different vertical lines, forms the openings (1059) in a layer made of the same material each time each light-emitting unit is laminated, and forms a metal layer (1060). Therefore, the pixel element (1000) of the present embodiment does not have to form the openings (1059) by patterning multiple layers made of different materials at once, so the convenience of the process is improved, the process is further simplified, and cost and time can be saved.

[0265] In the drawing explaining the pixel element (1000) according to the first embodiment, each metal layer (1060) is illustrated as being formed as a single layer and a single material. However, the metal layer (1060) of the present embodiment may have a multilayer structure. That is, the metal layer (1060) may be formed of multiple layers, and at least one of the multiple layers may be formed of a different material from the other layers.

[0266] In addition, although the pixel element (1000) according to the first embodiment has been described as having the first light emitting unit (1100) emitting green light, the second light emitting unit (1200) emitting blue light, and the third light emitting unit (1300) emitting red light, the present invention is not limited thereto. The first light emitting unit (1100), the second light emitting unit (1200), and the third light emitting unit (1300) emit at least one of green light, blue light, and red light, and may emit light of different colors. For example, the first light emitting unit (1100) may emit blue light, the second light emitting unit (1200) may emit green light, and the third light emitting unit (1300) may emit red light.

[0267] FIGS. 40 to 42 are drawings for explaining a pixel element (2000) according to a second embodiment of the present invention. FIG. 40 is a schematic plan view of a pixel element according to a second embodiment of the present invention. FIG. 41 is a cross-sectional view (G1-G2) for explaining a pixel element (2000) according to a second embodiment of the present invention. In addition, FIG. 42 is another cross-sectional view (G3-G4) for explaining a pixel element (2000) according to a second embodiment of the present invention.

[0268] The pixel element (2000) of the present embodiment has a metal layer (2060) that is different in structure from the metal layer (1060) of the pixel element (1000) of the first embodiment.

[0269] The metal layer (2060) formed in the opening (1059) of the transparent layer (1070) is formed to cover a portion of the inner wall and the bottom surface of the opening (1059). For example, when the metal layer (2060) is formed by a deposition technique, the metal layer (2060) may be formed along the bottom surface of one inner wall of the opening (1059) and may be formed to cover a portion of the other inner wall. By the metal layer (2060) formed in this structure, a portion of the inner wall of the transparent layer (1070) may be exposed in the opening (1059). That is, a portion of the metal layer (2060) may be formed to have an asymmetrical cross-section within the opening (1059).

[0270] More specifically, the portions formed in the 2-1 opening (1251) and the 2-2 opening (1252) of the 1st transparent layer (1170) among the 2-1 metal layer (2261) and the 2-2 metal layer (2262) and the portions formed in the 3-1 opening (1351), the 3-2 opening (1352) and the 3-4 opening (1354) of the 2nd transparent layer (1270) among the 3-1 metal layer (2361), the 3-2 metal layer (2362) and the 3-3 metal layer (2363) can be formed along the inner wall and bottom surface of each of the openings (1059). At this time, a portion of the inner wall of the 2-1 opening (1251), the 2-2 opening (1252), the 3-1 opening (1351), the 3-2 opening (1352), and the 3-4 opening (1354) may be exposed to the outside by the metal layer (2060) formed in each of the openings (11059). Here, the inner wall of the 2nd opening (1259) exposed to the outside by the metal layer (2060) is the first transparent layer (1170) and the second insulating layer (1250), and the inner wall of the 3rd opening (1359) exposed to the outside by the metal layer (2060) is the second transparent layer (1270) and the third insulating layer (1350).

[0271] The second transparent layer (1270) can be formed to fill the 2-1 opening (1251) and the 2-2 opening (1252). Accordingly, a portion of the first transparent layer (1170) in the 2-1 opening (1251) and the 2-2 opening (1252) can be in contact with the second metal layer (2260), and another portion can be in contact with the second transparent layer (1270).

[0272] In this way, the second transparent layer (1270) fills some of the second openings (1259), so that it can cover the ends of the second metal layer (2260) within the second openings (1259). Therefore, in the present embodiment, the second transparent layer (1270) can prevent the ends of the second metal layer (2260) from being peeled off within the second openings (1259).

[0273] Additionally, the pixel element (2000) may include a protective layer (2080) formed on top of the third light-emitting portion (1300), the third metal layer (2360), and the second transparent layer (1270) to cover them. The protective layer (2080) may be formed of an insulating material. Additionally, the protective layer (2080) may be formed of a material that reflects light or may include a material that reflects light. Additionally, the protective layer (2080) may be formed of a material that transmits light, as needed.

[0274] The protective layer (2080) may be formed to fill the third opening (1359). More specifically, the protective layer (2080) may be formed to fill the third-first opening (2351), the third-second opening (2352), and the third-fourth opening (2354). Accordingly, in some of the third openings (2359), a portion of the second transparent layer (1270) may be in contact with the third metal layer (2360), and another portion may be in contact with the protective layer (2080).

[0275] Additionally, since the protective layer (2080) fills some of the third openings (1359), it can cover the ends of the third metal layer (2360) within the third openings (1359). Accordingly, the protective layer (2080) can prevent the ends of the third metal layer (2360) within the third openings (1359) from being peeled off.

[0276] FIGS. 43 to 45 are drawings for explaining a pixel element (3000) according to a third embodiment of the present invention. FIG. 43 is a schematic plan view of a pixel element according to a third embodiment of the present invention. FIG. 44 is a cross-sectional view (H1-H2) for explaining a pixel element (3000) according to a third embodiment of the present invention. In addition, FIG. 45 is another cross-sectional view (H3-H4) for explaining a pixel element (3000) according to a third embodiment of the present invention.

[0277] The pixel element (3000) of the present embodiment has a metal layer (3060) that is different in structure from the metal layer (1060) of the pixel element (1000) of the first embodiment.

[0278] The metal layer (3060) formed in the opening (1059) of the transparent layer (1070) is formed to cover a part of the inner wall and the bottom surface of the opening (1059). For example, when the metal layer (3060) is formed by a deposition technique, the metal layer (3060) may be formed along the bottom surface of one inner wall of the opening (1059), but may be formed to cover only a part of the bottom surface. That is, a part of the metal layer (3060) may be formed to have an asymmetrical cross-section within the opening (1059). By the metal layer (3060) formed in such a structure, a part of the inner wall of the transparent layer (1070) in the opening (1059) and a part of the metal layer (3060) located at the bottom of the opening (1059) may be exposed.

[0279] More specifically, the portions formed in the 2-1 opening (1251) and the 2-2 opening (1252) of the first transparent layer (1170) among the 2-1 metal layer (3261) and the 2-2 metal layer (3262) and the portions formed in the 3-1 opening (1351), the 3-2 opening (1352) and the 3-4 opening (1354) of the second transparent layer (1270) among the 3-1 metal layer (3361), the 3-2 metal layer (3362) and the 3-3 metal layer (3363) may be formed along the inner wall and the bottom surface to cover a portion of one inner wall and a bottom surface of each of the openings (1059). At this time, a portion of the inner wall of the 2-1 opening (1251), the 2-2 opening (1252), the 3-1 opening (1351), the 3-2 opening (1352), and the 3-4 opening (1354) may be exposed to the outside by the metal layer (3060) formed in each opening (11059). Here, the inner wall of the 2nd opening (1259) exposed to the outside by the metal layer (3060) is the first transparent layer (1170) and the second insulating layer (1250), and the inner wall of the 3rd opening (3359) is the second transparent layer (1270) and the third insulating layer (1350). Additionally, a portion of the upper surface of the 1-1 metal layer (1161), the 1-2 metal layer (1162), the 2-1 metal layer (3261), the 2-2 metal layer (3262), and the 2-3 metal layer (3263) located at the lower portion of the 2-1 opening (1251), the 2-2 opening (1252), the 3-1 opening (1351), the 3-2 opening (1352), and the 3-4 opening (1354) may also be exposed to the outside.

[0280] The second transparent layer (1270) can be formed to fill the 2-1 opening (1251) and the 2-2 opening (1252). Accordingly, a part of the first transparent layer (1170) in the 2-1 opening (1251) and the 2-2 opening (1252) can be in contact with the second metal layer (3260), and another part can be in contact with the second transparent layer (1270). In addition, a part of the second transparent layer (1270) in the 2-1 opening (1251) and the 2-2 opening (1252) can be in contact with the first transparent layer (1170), another part can be in contact with the first metal layer (1160), another part can be in contact with the second metal layer (3260), and another part can be in contact with the second insulating layer (1250).

[0281] In this way, the second transparent layer (1270) fills some of the second openings (1259), so that it can cover the ends of the second metal layer (3260) within the second openings (1259). Therefore, in the present embodiment, the second transparent layer (1270) can prevent the ends of the second metal layer (3260) from being peeled off within the second openings (1259).

[0282] Additionally, the pixel element (3000) may include a protective layer (2080) formed on top of the third light-emitting portion (1300), the third metal layer (3360), and the second transparent layer (1270) to cover them. The protective layer (2080) may be formed of an insulating material. Additionally, the protective layer (2080) may be formed of a material that reflects light or may include a material that reflects light. Additionally, the protective layer (2080) may be formed of a material that transmits light, as needed.

[0283] The protective layer (2080) may be formed to fill the third opening (1359). More specifically, the protective layer (2080) may be formed to fill the third-first opening (3351), the third-second opening (3352), and the third-fourth opening (3354). Accordingly, in the third-first opening (3351), the third-second opening (3352), and the third-fourth opening (3354), a portion of the protective layer (2080) may be in contact with the second transparent layer (1270), another portion may be in contact with the second metal layer (3260), another portion may be in contact with the third metal layer (3360), and another portion may be in contact with the third insulating layer (1350).

[0284] Additionally, since the protective layer (2080) fills some of the third openings (1359), it can cover the ends of the third metal layer (3360) within the third openings (1359). Accordingly, the protective layer (2080) can prevent the ends of the third metal layer (3360) within the third openings (1359) from being peeled off.

[0285] Also, referring to FIG. 45, the width (W3) of the first-second metal layer (1162) in contact with the second-second metal layer (3262) in the second-second opening (1252) may be greater than the width (W4) of the first-second metal layer (1162) in contact with the second transparent layer (1270). Furthermore, the area in which the first-second metal layer (1162) is in contact with the second-second metal layer (3262) in the second-second opening (1252) may be greater than the area in which the first-second metal layer (1162) is in contact with the second transparent layer (1270). Also, referring to FIG. 44, the width or area of ​​the 1-1 metal layer (1161) in contact with the 2-1 metal layer (3261) in the 2-1 opening (1251) may be greater than the width or area of ​​the 1-1 metal layer (1161) in contact with the second transparent layer (1270). Also, referring to FIGS. 44 and 45, the width or area of ​​the 2nd metal layer (3260) in contact with the 3rd metal layer (3360) in the 3rd opening (1359) may be greater than the width or area of ​​the 2nd metal layer (3260) in contact with the protective layer (2080).

[0286] FIG. 46 and FIG. 47 are drawings for explaining a pixel element (4000) according to a fourth embodiment of the present invention. FIG. 46 is a cross-sectional view for explaining a pixel element (4000) according to a fourth embodiment of the present invention. More specifically, FIG. 46 is a cross-sectional view corresponding to A1-A2 based on the plan view of FIG. 2. In addition, FIG. 47 is another cross-sectional view for explaining a pixel element (4000) according to a fourth embodiment of the present invention. More specifically, FIG. 47 is a cross-sectional view corresponding to A3-A4 based on the plan view of FIG. 2.

[0287] The pixel element (4000) of the present embodiment has a metal layer (4060) whose structure is different from that of the pixel element (1000) of the first embodiment.

[0288] The pixel element (4000) according to the present embodiment is formed such that the metal layer (1060) formed in the opening (1059) covers the inner wall of the opening (1059) and fills the interior of the opening (1059).

[0289] For example, referring to FIG. 46, the 2-1 metal layer (4261), the 3-1 metal layer (4361), and the 3-3 metal layer (4363) are formed to fill the 2-1 opening (1251), the 3-3 opening (1353), and the 3-4 opening (1354), respectively.

[0290] Also, referring to FIG. 47, the 2-2 metal layer (4262) and the 3-2 metal layer (4362) are formed to fill the 2-2 opening (1252) and the 3-2 opening (1352), respectively.

[0291] When the metal layer (1060) is formed to fill the opening (1059) in this way, the metal layer (1060) can be formed using a plating technique.

[0292] In the drawings for explaining the pixel elements (1000, 4000) of the first and fourth embodiments, a protective layer (2080) is not shown, but a protective layer (2080) may be added as needed.

[0293] The pixel element of the present invention can form a metal layer in various structures as described through the first to fourth embodiments.

[0294] FIGS. 48 to 71 are drawings for explaining a pixel element and a manufacturing method thereof according to a fifth embodiment of the present invention.

[0295] Referring to FIGS. 70 and 71, a pixel element (5001) according to the fifth embodiment may include a first base (1110), a first light-emitting unit (5000), a second light-emitting unit (6000), and a third light-emitting unit (7000). According to the present embodiment, the first light-emitting unit (5000) may emit green light or blue light, the second light-emitting unit (6000) may emit blue light or green light, and the third light-emitting unit (7000) may emit red light. However, the present embodiment is not limited thereto. The first light-emitting unit (5000), the second light-emitting unit (6000), and the third light-emitting unit (7000) may emit one of green light, blue light, and red light, and may emit light of different colors.

[0296] Referring to FIGS. 48 to 62, the first to third light-emitting portions (5000, 6000, 7000) can be formed individually.

[0297] FIGS. 48 to 52 are drawings for explaining the first light-emitting portion (5000) of the pixel element (5001) of the fifth embodiment of the present invention and the manufacturing method thereof.

[0298] Referring to FIGS. 48 to 52, a first light-emitting portion (5000) may be formed on a first base (1110). The first light-emitting portion (5000) may include a first semiconductor structure, a first ohmic electrode (5104), a first insulating layer (5200), and a first metal layer (5300).

[0299] Referring to FIG. 48, a first semiconductor structure can be formed on a first base (1110). The first semiconductor structure can include a first-first semiconductor layer (5101), a first active layer (5102), and a first-second semiconductor layer (5103).

[0300] According to the present embodiment, the first base (1110) may be a growth substrate capable of growing a semiconductor layer. For example, the first base (1110) may be sapphire. The first base (1110) is not necessarily included in the final product form, and may be removed.

[0301] The first-first semiconductor layer (5101) may be formed on top of the first base (1110), the first active layer (5102) may be formed on top of the first-first semiconductor layer (5101), and the first-second semiconductor layer (5103) may be formed on top of the first active layer (5102).

[0302] The first semiconductor structure can be formed using metal organic chemical vapor deposition (MOCVD) technology or molecular beam epitaxy (MBE) technology. The second semiconductor structure of the second light-emitting portion (6000) and the third semiconductor structure of the third light-emitting portion (7000) can also be formed using the same method.

[0303] The first semiconductor layer (5101) may be an n-type conductive semiconductor layer, and the first semiconductor layer (5103) may be a p-type conductive semiconductor layer. Or vice versa. For example, the first semiconductor structure may include a semiconductor material that emits green light or blue light, such as GaN, InGaN, AlGaN, InAlGaN, GaP, AlGaInP, AlGaP, etc.

[0304] Referring to FIG. 49, a first semiconductor structure may be patterned to form a first mesa structure (5110). A portion of the first active layer (5102) and the 1-2 semiconductor layer (5103) may be etched to expose a portion of the upper surface of the 1-1 semiconductor layer (5101). After the etching process, the first active layer (5102) and the 1-2 semiconductor layer (5103) remaining on the upper surface of the 1-1 semiconductor layer (5101) and a portion of the 1-1 semiconductor layer (5101) may become a first mesa structure (5110).

[0305] The first mesa structure (5110) has a structure in which the side surface is vertical with respect to the upper surface of the first-first semiconductor layer (5101). However, the structure of the first mesa structure (5110) is not limited thereto. For example, the first mesa structure (5110) may have a structure in which the width and cross-sectional area become narrower from the lower surface of the first active layer (5102) to the upper surface of the first-second semiconductor layer (5103). That is, the first mesa structure (5110) may have a structure in which the side surface is inclined. The mesa structures of the second light-emitting portion (6000) and the third light-emitting portion (7000) described below may also be formed in a structure in which the side surface is vertical or inclined with respect to the upper surface of the first semiconductor layer.

[0306] According to the present embodiment, the first mesa structure (5110) may include a first light-emitting structure (5111) and a first buffer structure (5112). That is, a part of the first mesa structure (5110) may be the first light-emitting structure (5111), and another part of the first mesa structure (5110) may be the first buffer structure (5112). The first light-emitting structure (5111) and the first buffer structure (5112) may be arranged on the same plane.

[0307] The first buffer structure (5112) can share the first light-emitting structure (5111) and the first-first semiconductor layer (5101). Therefore, the first buffer structure (5112) can be electrically connected to an electrode that is electrically connected to the first-first semiconductor layer (5101) of the first light-emitting structure (5111), but can maintain a non-light-emitting state.

[0308] In another embodiment, the first buffer structure (5112) may be disposed spaced apart from the first light-emitting structure (5111), and the first buffer structure (5112) and the first light-emitting structure (5111) may be separated by a first transparent layer (8100). Accordingly, the first buffer structure (5112) may be electrically insulated and may maintain a non-light-emitting state. Accordingly, a contact area may be created between the first transparent layer (8100) and the second transparent layer (8200).

[0309] The first light-emitting structure (5111) can be a light-emitting region that emits light when electricity is supplied to the first light-emitting unit (5000). However, the first buffer structure (5112) does not emit light even when electricity is supplied to the first light-emitting unit (5000). The first buffer structure (5112) can be spaced apart from the first light-emitting structure (5111) and maintain a non-light-emitting state regardless of the light emission of the first light-emitting structure (5111).

[0310] Referring to Fig. 48, the upper surface of the first base (1110) or the 1-1 semiconductor layer (5101) can be divided into 9 regions (3x3). The 9 regions can be the 1-1 region to the 1-9 region (R11, R12, R13, R14, R15, R16, R17, R18, R19).

[0311] The first light-emitting structure (5111) is formed on the 1-4 region (R14), the 1-6 region (R16), the 1-8 region (R18), and the central 1-5 region (R15), and the first light-emitting structures (5111) formed in each region are connected to each other. That is, the first light-emitting structure (5111) is formed of a plurality of regions extending in different directions from the central 1-5 region (R15).

[0312] The first buffer structure (5112) may be positioned in an area where the first light-emitting structure (5111) is not formed. The first buffer structure (5112) may be positioned at each corner based on the plane of the first base (1110). The first buffer structure (5112) may include a 1-1 buffer structure (5115), a 1-2 buffer structure (5116), a 1-3 buffer structure (5117), and a 1-4 buffer structure (5118) formed adjacent to each corner of the first base (1110) or the 1-1 semiconductor layer (5101). Referring to FIG. 49, the 1-1 buffer structure (5115) may be formed on the 1-1 region (R11), the 1-2 buffer structure (5116) may be formed on the 1-3 region (R13), the 1-3 buffer structure (5117) may be formed on the 1-7 region (R17), and the 1-4 buffer structure (5118) may be formed on the 1-9 region (R19).

[0313] Based on the first buffer structure (5112), the first light-emitting structure (5111) is positioned between the first buffer structures (5112). Referring to FIG. 49, the first light-emitting structure (5111) is formed in the 1-8 region (R18) between the 1-3 buffer structure (5117) and the 1-4 buffer structure (5118), the 1-4 region (R14) between the 1-1 buffer structure (5115) and the 1-3 buffer structure (5117), the 1-6 region (R16) between the 1-2 buffer structure (5116) and the 1-4 buffer structure (5118), and the 1-5 region (R15) in the center, and the light-emitting structures formed in each region are connected to each other.

[0314] The first buffer structure (5112) and the first light-emitting structure (5111) are formed through the same etching process, so that their respective upper surfaces can have the same height.

[0315] In the present embodiment, the first light-emitting unit (5000) is provided with a plurality of first buffer structures (5112), but is provided with a single first light-emitting structure (5111). However, the structure of the first light-emitting unit (5000) is not limited thereto, and may be provided with a plurality of first light-emitting structures (5111) or a single first buffer structure (5112).

[0316] Referring to FIG. 50, a first ohmic electrode (5104) may be formed on a first light-emitting structure (5111). More specifically, the first ohmic electrode (5104) may be formed to cover the upper surface of the first-second semiconductor layer (5103) of the first light-emitting structure (5111).

[0317] The first ohmic electrode (5104) may have high transmittance and high electrical conductivity for light emitted from the first light-emitting structure (5111). For example, the first ohmic electrode (5104) may be a transparent electrode. Furthermore, the first ohmic electrode (5104) may be ITO (Indium Tin Oxide). In the present embodiment, the first light-emitting structure (5111) may include not only the first active layer (5102) and the first-second semiconductor layer (5103), but also the first ohmic electrode (5104). That is, the first ohmic electrode (5104) may also be included in the first mesa structure (5110).

[0318] Although the first ohmic electrode (5104) is formed only on the upper portion of the first-second semiconductor layer (5103) of the first light-emitting structure (5111), the present embodiment is not limited thereto. When the first ohmic electrode (5104) is formed on the upper portion of the first-second semiconductor layer (5103) of the first light-emitting structure (5111), the first ohmic electrode (5104) may also be formed on the upper portion of the first-second semiconductor layer (5103) of the first buffer structure (5112).

[0319] Referring to FIG. 51, a first insulating layer (5200) may be formed. The first insulating layer (5200) may be formed to cover the first mesa structure (5110) and the first-first semiconductor layer (5101) exposed to the outside by the first mesa structure (5110).

[0320] The first insulating layer (5200) may be formed of a light-transmitting material. For example, the first insulating layer (5200) may be formed of a silicon oxide such as SiO2, a silicon nitride such as Si3N4, or a silicon oxynitride.

[0321] The first insulating layer (5200) may include a first opening (5210). In addition, the first opening (5210) may include a first-first opening (5211) exposing the first-first semiconductor layer (5101) and a first-second opening (5212) exposing the first ohmic electrode (5104).

[0322] Referring to FIG. 51, the first-first opening (5211) may be located on the upper portion of the first-first semiconductor layer (5101) between the first-first buffer structure (5115) and the first-second buffer structure (5116). In addition, the first-second opening (5212) may be located on the upper portion of the first ohmic electrode (5104) of the first light-emitting structure (5111) between the first-third buffer structure (5117) and the first-fourth buffer structure (5118).

[0323] Referring to FIG. 52, a first metal layer (5300) can be formed. The first metal layer (5300) can be formed to fill the first opening (5210) of the first insulating layer (5200).

[0324] The first metal layer (5300) may be formed of a conductive material. For example, the first metal layer (5300) may be formed of at least one metal. Additionally, the first metal layer (5300) may be formed as a single layer or multiple layers.

[0325] The first metal layer (5300) may include a first-first metal layer (5301) and a first-second metal layer (5302).

[0326] The first-first metal layer (5301) is formed to fill the first-first opening (5211) and can be in contact with the first-first semiconductor layer (5101). Therefore, the first-first metal layer (5301) can be electrically connected to the first-first semiconductor layer (5101). In addition, the first-first metal layer (5301) can be formed to further cover the upper surface of the first insulating layer (5200) adjacent to the first-first opening (5211). That is, the cross-sectional area or width of the upper surface of the first-first metal layer (5301) can be larger than the cross-sectional area or width of the first-first opening (5211).

[0327] The first-second metal layer (5302) is formed to fill the first-second opening (5212) and can be in contact with the first ohmic electrode (5104). Therefore, the first-second metal layer (5302) can be electrically connected to the first ohmic electrode (5104) and the first-second semiconductor layer (5103). In addition, the first-second metal layer (5302) can be formed to further cover the upper surface of the first insulating layer (5200) adjacent to the first-second opening (5212). That is, the cross-sectional area or width of the upper surface of the first-second metal layer (5302) can be larger than the cross-sectional area or width of the first-second opening (5212).

[0328] When electricity is supplied through the first-first metal layer (5301) connected to the first-first semiconductor layer (5101) and the first-second metal layer (5302) connected to the first light-emitting structure (5111), light can be emitted from the first light-emitting structure (5111) by the current flow passing through the first light-emitting structure (5111). However, since no current flow is formed in the first buffer structure (5112), the first buffer structure (5112) can maintain a non-light-emitting state even when electricity is supplied to the first light-emitting unit (5000).

[0329] The first base (1110) is not limited to a growth substrate. The first base (1110) may also be formed of a light-transmitting material, such as silicon or epoxy. For example, after the first light-emitting portion (5000) is formed on the growth substrate, the growth substrate may be removed, and the first light-emitting portion (5000) may be placed on the first base (1110), which is a light-transmitting material.

[0330] FIGS. 53 to 57 are drawings for explaining the second light-emitting portion (6000) of the pixel element (5001) of the fifth embodiment of the present invention and the manufacturing method thereof.

[0331] Referring to FIGS. 53 to 57, a second light-emitting portion (6000) may be formed on a second base (1210). The second light-emitting portion (6000) may include a second semiconductor structure, a second ohmic electrode (6104), a second insulating layer (6200), and a second metal layer (6300).

[0332] Referring to FIGS. 53 and 54, a second semiconductor structure can be formed on a second base (1210). The second semiconductor structure can include a second-first semiconductor layer (6101), a second active layer (6102), and a second-second semiconductor layer (6103).

[0333] According to the present embodiment, the second base (1210) may be a growth substrate capable of growing a semiconductor layer. For example, the second base (1210) may be sapphire.

[0334] The semiconductor structure can be formed using metal organic chemical vapor deposition (MOCVD) technology or molecular beam epitaxy (MBE) technology. The second semiconductor structure of the second light-emitting portion (6000) and the third semiconductor structure of the third light-emitting portion (7000) can also be formed in the same manner.

[0335] The second-1 semiconductor layer (6101) may be an n-type conductive semiconductor layer, and the second-2 semiconductor layer (6103) may be a p-type conductive semiconductor layer. Or vice versa. For example, the second semiconductor structure may include a semiconductor material that emits blue light or green light, such as GaN, InGaN, AlGaN, InAlGaN, ZnSe, etc.

[0336] Referring to FIG. 53, a second-first semiconductor layer (6101) may be formed on the second base (1210). At this time, as illustrated in FIG. 53, the second-first semiconductor layer (6101) may be formed in an area excluding an area corresponding to the upper portion of the first metal layer (5300) of the first light-emitting unit (5000) when the second light-emitting unit (6000) is later placed on the upper portion of the first light-emitting unit (5000).

[0337] Referring to FIG. 54, a second mesa structure (6110) composed of a second active layer (6102) and a second-second semiconductor layer (6103) may be formed on top of a second-first semiconductor layer (6101). The second mesa structure (6110) may be formed to cover a portion of the upper surface of the second-first semiconductor layer (6101) and expose another portion of the upper surface. The second mesa structure (6110) may be formed to have a structure having vertical or inclined side surfaces based on the upper surface of the second-first semiconductor layer (6101).

[0338] The second mesa structure (6110) may include a second light-emitting structure (6111) and a second buffer structure (6112).

[0339] The second light-emitting structure (6111) can be a light-emitting region that emits light when electricity is supplied to the pixel element (5001) or the second light-emitting unit (6000). However, the second buffer structure (6112) does not emit light even when electricity is supplied to the second light-emitting unit (6000). The second buffer structure (6112) can be spaced apart from the second light-emitting structure (6111) and maintain a non-light-emitting state regardless of the light emission of the second light-emitting structure (6111).

[0340] The second light-emitting structure (6111) and the second buffer structure (6112) are formed in different regions. More specifically, the second buffer structure (6112) may be formed in a region where the second light-emitting structure (6111) is not formed. The second light-emitting structure (6111) and the second buffer structure (6112) may be arranged on the same plane.

[0341] The second buffer structure (6112) can share the second light-emitting structure (6111) and the second-first semiconductor layer (6101). Therefore, the second buffer structure (6112) can be electrically connected to an electrode that is electrically connected to the second-first semiconductor layer (6101) of the second light-emitting structure (6111), but can maintain a non-light-emitting state.

[0342] In another embodiment, the second buffer structure (6112) may be disposed spaced apart from the second light-emitting structure (6111), and the second buffer structure (6112) and the second light-emitting structure (6111) may be separated by a second transparent layer (8200). Accordingly, the second buffer structure (6112) may be electrically insulated and may maintain a non-light-emitting state. Accordingly, a contact area may be created between the first transparent layer (8100) and the second transparent layer (8200), and a contact area may be created between the second transparent layer (8200) and the third transparent layer (8300).

[0343] Referring to Fig. 54, the upper surface of the second base (1210) can be divided into nine regions. The nine regions can be regions 2-1 to 2-9 (R21, R22, R23, R24, R25, R26, R27, R28, R29) similar to those in Fig. 48.

[0344] The second buffer structure (6112) may include a second-first buffer structure (6115), a second-second buffer structure (6116), and a second-third buffer structure (6117). Referring to FIG. 54, the second-first buffer structure (6115) may be formed on the second-first region (R21), the second-second buffer structure (6116) may be formed on the second-seventh region (R27), and the second-third buffer structure (6117) may be formed on the second-ninth region (R29). At this time, when the second light emitting unit (6000) is placed on the first light emitting unit (5000), the 2-1 buffer structure (6115) may be positioned on top of the 1-1 buffer structure (5115), the 2-2 buffer structure (6116) may be positioned on top of the 1-3 buffer structure (5117), and the 2-3 buffer structure (6117) may be positioned on top of the 1-4 buffer structure (5118).

[0345] The second-first light-emitting structure (6111) can be formed in an area on the upper surface of the second-first semiconductor layer (6101) where the second buffer structure (6112) is not formed. That is, referring to FIG. 54, the second light-emitting structure (6111) is formed in the second-third region (R23), the second-fourth region (R24), the second-fifth region (R25), and the second-sixth region (R26), and the second light-emitting structures (6111) formed in each region are connected to each other. That is, the second light-emitting structure (6111) is formed of a plurality of regions extending in different directions from the second-fifth region (R25), which is the center.

[0346] The second buffer structure (6112) and the second light-emitting structure (6111) are formed through the same etching process, so that their respective upper surfaces can have the same height.

[0347] In the present embodiment, the second light-emitting unit (6000) is provided with a plurality of second buffer structures (6112), but is provided with a single second light-emitting structure (6111). However, the structure of the second light-emitting unit (6000) is not limited thereto, and may be provided with a plurality of second light-emitting structures (6111) or a single second buffer structure (6112).

[0348] Referring to FIG. 55, a second ohmic electrode (6104) may be formed on a second light-emitting structure (6111). More specifically, the second ohmic electrode (6104) may be formed to cover the upper surface of the second-second semiconductor layer (6103) of the second light-emitting structure (6111).

[0349] The second ohmic electrode (6104) may have high transmittance and high electrical conductivity for light emitted from the second light-emitting structure (6111). For example, the second ohmic electrode (6104) may be a transparent electrode. Furthermore, the second ohmic electrode (6104) may be ITO (Indium Tin Oxide). In the present embodiment, the second light-emitting structure (6111) may include not only the second active layer (6102) and the second-second semiconductor layer (6103), but also the second ohmic electrode (6104). That is, the second ohmic electrode (6104) may also be included in the second mesa structure (6110).

[0350] In FIG. 55, the second ohmic electrode (6104) is formed only on the upper surface of the second-second semiconductor layer (6103) of the second light-emitting structure (6111), but the present embodiment is not limited thereto. The second ohmic electrode (6104) may be formed not only on the second light-emitting structure (6111) but also on the upper surface of the second buffer structure (6112).

[0351] Referring to FIG. 56, a second insulating layer (6200) may be formed. The second insulating layer (6200) may be formed to cover the second mesa structure (6110) and the second-1 semiconductor layer (6101) exposed to the outside by the second mesa structure (6110).

[0352] The second insulating layer (6200) may be formed of a light-transmitting material. For example, the second insulating layer (6200) may be formed of a silicon oxide such as SiO2, a silicon nitride such as Si3N4, or a silicon oxynitride.

[0353] The second insulating layer (6200) may include a second opening (6210). In addition, the second opening (6210) may include a second-first opening (6211), a second-second opening (6212), and a second-third opening (6213).

[0354] Referring to FIG. 56, the 2-1 opening (6211) may be formed between the side surfaces of the 2-1 semiconductor layer (6101) and the second light-emitting structure, which face each other on one side of the 2-1 buffer structure (6115). In addition, the 2-2 opening (6212) may be formed between the side surfaces of the 2-1 semiconductor layer (6101) that face each other on one side of the 2-2 buffer structure (6116). That is, the 2-1 opening (6211) and the 2-2 opening (6212) may be formed in an area where the second semiconductor structures are not formed to expose the upper surface of the second base (1210).

[0355] Additionally, the 2-1 opening (6211) may be formed to expose a portion of one side of the 2-1 semiconductor layer (6101), as illustrated in FIG. 56.

[0356] When the second light-emitting portion (6000) is positioned above the first light-emitting portion (5000), the 2-1 opening (6211) can be formed so that at least a portion thereof is positioned above the 1-1 opening (5211) or above the 1-1 metal layer (5301). In addition, the 2-2 opening (6212) can be formed so that at least a portion thereof is positioned above the 1-2 opening (5212) or above the 1-2 metal layer (5302).

[0357] The 2-3 opening (6213) may be positioned above the second ohmic electrode (6104) of the second light-emitting structure (6111). Accordingly, the 2-3 opening (6213) may be formed to expose the upper surface of the second ohmic electrode (6104) of the second light-emitting structure (6111). In addition, when the second light-emitting unit (6000) is arranged above the first light-emitting unit (5000), the 2-3 opening (6213) may be formed to be positioned above the 1-2 buffer structure (5116) of the first light-emitting unit (5000).

[0358] Referring to FIG. 57, a second metal layer (6300) may be formed. The second metal layer (6300) may be formed to fill the second opening (6210) of the second insulating layer (6200).

[0359] The second metal layer (6300) may be formed of a conductive material. For example, the second metal layer (6300) may be formed of at least one metal. Additionally, the second metal layer (6300) may be formed as a single layer or multiple layers.

[0360] The second metal layer (6300) may include a second-first metal layer (6301), a second-second metal layer (6302), and a second-third metal layer (6303).

[0361] The second-first metal layer (6301) may be formed to fill the second-first opening (6211). At this time, the second-first metal layer (6301) may be in contact with the second-first semiconductor layer (6101) through the second-first opening (6211) that exposes a portion of one side surface of the second-first semiconductor layer (6101). That is, the second-first metal layer (6301) may be electrically connected to the second-first semiconductor layer (6101). In addition, the second-first metal layer (6301) may be formed to further cover the upper surface of the second insulating layer (6200) adjacent to the second-first opening (6211). That is, the cross-sectional area or width of the upper surface of the second-first metal layer (6301) may be larger than the cross-sectional area or width of the second-first opening (6211).

[0362] The second-second metal layer (6302) may be formed to fill the second-second opening (6212). In addition, the second-second metal layer (6302) may be formed to further cover the upper surface of the second insulating layer (6200) adjacent to the second-second opening (6212). That is, the cross-sectional area or width of the upper surface of the second-second metal layer (6302) may be larger than the cross-sectional area or width of the second-second opening (6212).

[0363] The 2-3 metal layer (6303) may be formed to fill the 2-3 opening (6213). At this time, the 2-3 metal layer (6303) may be in contact with the second ohmic electrode (6104). Therefore, the 2-3 metal layer (6303) may be electrically connected to the second ohmic electrode (6104) and the 2-2 semiconductor layer (6103). In addition, the 2-3 metal layer (6303) may be formed to further cover the upper surface of the second insulating layer (6200) adjacent to the 2-3 opening (6213). That is, the cross-sectional area or width of the upper surface of the 2-3 metal layer (6303) may be larger than the cross-sectional area or width of the 2-3 opening (6213).

[0364] When electricity is supplied through the second-1 metal layer (6301) connected to the second-1 semiconductor layer (6101) and the second-3 metal layer (6303) connected to the second light-emitting structure (6111), light can be emitted from the second light-emitting structure (6111). However, since no current flow is formed in the second buffer structure (6112), the second buffer structure (6112) can maintain a non-light-emitting state even when electricity is supplied to the second light-emitting unit (6000).

[0365] FIGS. 58 to 62 are drawings for explaining the third light-emitting portion (7000) of the pixel element (5001) of the fifth embodiment of the present invention and its manufacturing method.

[0366] Referring to FIGS. 58 to 62, a third light-emitting portion (7000) may be formed on a third base (1310). The third light-emitting portion (7000) may include a third semiconductor structure, a third ohmic electrode (7104), a third insulating layer (7200), and a third metal layer (7300).

[0367] Referring to FIGS. 58 and 59, a third semiconductor structure can be formed on a third base (1310). The third semiconductor structure can include a third-first semiconductor layer (7101), a third active layer (7102), and a third-second semiconductor layer (7103).

[0368] According to the present embodiment, the third base (1310) may be a growth substrate capable of growing a semiconductor layer. For example, the third base (1310) may be sapphire.

[0369] The third semiconductor structure can be formed using metal organic chemical vapor deposition (MOCVD) technology or molecular beam epitaxy (MBE) technology. The third semiconductor structure of the third light-emitting portion (7000) and the third semiconductor structure of the third light-emitting portion (7000) can also be formed in the same manner.

[0370] The third-first semiconductor layer (7101) may be an n-type conductive semiconductor layer, and the third-second semiconductor layer (7103) may be a p-type conductive semiconductor layer. Or vice versa. For example, the third semiconductor structure may include a semiconductor material that emits red light, such as AlGaAs, GaAsP, AlGaInP, GaP, or the like.

[0371] Referring to FIG. 58, a 3-1 semiconductor layer (7101) may be formed on a 3rd base (1310). At this time, as illustrated in FIG. 58, the 3-1 semiconductor layer (7101) may be formed in an area excluding an area corresponding to an upper portion of the first metal layer (5300) of the first light-emitting unit (5000) when the 3rd light-emitting unit (7000) is later placed on the upper portion of the 1st light-emitting unit (5000) and the 2nd light-emitting unit (6000).

[0372] Referring to FIGS. 58 and 59, the upper surface of the third base (1310) can be divided into nine regions. The nine regions can be regions 3-1 to 3-9 (R31, R32, R33, R34, R35, R36, R37, R38, R39).

[0373] Referring to FIG. 58, the 3-1 semiconductor layer (7101) is formed on the 3-1 region (R31), the 3-4 to 3-7 regions (R34, R35, R36, R37), and the 3-9 region (R39), and the 3-1 semiconductor layers (7101) formed in these regions can be connected to each other. In addition, the 3-1 semiconductor layer (7101) is formed on the inner side of the 3-3 region (R33), and can be formed to be spaced apart from other 3-1 semiconductor layers (7101).

[0374] Referring to FIG. 59, a third mesa structure (7110) composed of a third active layer (7102) and a third-second semiconductor layer (7103) may be formed on top of a third-first semiconductor layer (7101). The third mesa structure (7110) may be formed to cover a portion of the upper surface of the third-first semiconductor layer (7101) and expose another portion of the upper surface. The third mesa structure (7110) may be formed to have a structure having vertical or inclined side surfaces based on the upper surface of the third-first semiconductor layer (7101).

[0375] The third mesa structure (7110) may include a third light-emitting structure (7111) and a third buffer structure (7112).

[0376] The third light-emitting structure (7111) can be a light-emitting region that emits light when electricity is supplied to the pixel element (5001) or the third light-emitting unit (7000). However, the third buffer structure (7112) does not emit light even when electricity is supplied to the third light-emitting unit (7000). The third buffer structure (7112) can be spaced apart from the third light-emitting structure (7111) and maintain a non-light-emitting state regardless of the light emission of the third light-emitting structure (7111).

[0377] The third light-emitting structure (7111) and the third buffer structure (7112) are formed in different regions. More specifically, the third buffer structure (7112) may be formed in a region where the third light-emitting structure (7111) is not formed. The third light-emitting structure (7111) and the third buffer structure (7112) may be arranged on the same plane.

[0378] The third buffer structure (7112) can share the third light-emitting structure (7111) and the third-first semiconductor layer (7101). Therefore, the third buffer structure (7112) can be electrically connected to an electrode that is electrically connected to the third-first semiconductor layer (7101) of the third light-emitting structure (7111), but can maintain a non-light-emitting state.

[0379] In another embodiment, the third buffer structure (7112) may be disposed spaced apart from the third light-emitting structure (7111), and the third buffer structure (7112) and the third light-emitting structure (7111) may be separated by a third transparent layer (8300). Accordingly, the third buffer structure (7112) may be electrically insulated and may maintain a non-light-emitting state. Accordingly, a contact area may be created between the third transparent layer (8300) and the second transparent layer (8200).

[0380] The third buffer structure (7112) may include a third-first buffer structure (7115), a third-second buffer structure (7116), and a third-third buffer structure (7117). Referring to FIG. 59, the third-first buffer structure (7115) may be formed on the inner side of the third-first region (R31), the third-second buffer structure (7116) may be formed on the inner side of the third-third region (R33), and the third-third buffer structure (7117) may be formed on the inner side of the third-ninth region (R39). At this time, when the third light-emitting unit (7000) is arranged on the upper side of the first light-emitting unit (5000) and the second light-emitting unit (6000), the third-first buffer structure (7115) may be positioned on the upper side of the first-first buffer structure (5115) and the second-first buffer structure (6115). Additionally, the 3-2 buffer structure (7116) may be positioned on top of the 1-2 buffer structure (5116). Additionally, the 3-3 buffer structure (7117) may be positioned on top of the 1-4 buffer structure (5118) and the 2-3 buffer structure.

[0381] The third light-emitting structure (7111) can be formed in an area where the third buffer structure (7112) is not formed on the upper surface of the 3-1 semiconductor layer (7101). That is, referring to FIG. 59, the third light-emitting structure (7111) is formed in the 3-4 to 3-7 areas (R34, R35, R36, R37), and the third light-emitting structures (7111) formed in each area are connected to each other.

[0382] The third buffer structure (7112) and the third light-emitting structure (7111) may be formed through the same etching process and thus have the same height.

[0383] In the present embodiment, the third light-emitting unit (7000) is provided with a plurality of third buffer structures (7112), but is provided with a single third light-emitting structure (7111). However, the structure of the third light-emitting unit (7000) is not limited thereto, and may be provided with a plurality of third light-emitting structures (7111) or a single third buffer structure (7112).

[0384] Referring to FIG. 60, a third ohmic electrode (7104) may be formed on a third mesa structure (7110). That is, the third ohmic electrode (7104) may be formed to cover the third-2 semiconductor layer (7103).

[0385] The third ohmic electrode (7104) may have high electrical conductivity. In addition, the third ohmic electrode (7104) may have high optical transparency for light emitted from the third light-emitting structure (7111). For example, the third ohmic electrode (7104) may be a transparent electrode. Furthermore, the third ohmic electrode (7104) may be ITO (Indium Tin Oxide). In the present embodiment, the third mesa structure (7110) may include not only the third active layer (7102) and the third-second semiconductor layer (7103), but also the third ohmic electrode (7104).

[0386] In FIG. 60, the third ohmic electrode (7104) is formed on the entire upper surface of the third-2 semiconductor layer (7103), but may be omitted from the upper surface of the third-2 semiconductor layer (7103) of the third buffer structure (7112). That is, the third ohmic electrode (7104) may be formed only on the upper surface of the third-2 semiconductor layer (7103) of the third light-emitting structure (7111).

[0387] Referring to FIG. 61, a third insulating layer (7200) may be formed. The third insulating layer (7200) may be formed to cover the third mesa structure (7110) and the third-1 semiconductor layer (7101) exposed to the outside by the third mesa structure (7110).

[0388] The third insulating layer (7200) may be formed of a light-transmitting material. For example, the third insulating layer (7200) may be formed of a silicon oxide such as SiO2, a silicon nitride such as Si3N4, or a silicon oxynitride.

[0389] The third insulating layer (7200) may include a third opening (7210). In addition, the third opening (7210) may include a third-first opening (7211), a third-second opening (7212), a third-third opening (7213), and a third-fourth opening (7214).

[0390] Referring to FIG. 61, the 3-1 opening (7211) may be formed between the side surfaces of the 3-1 semiconductor layer (7101) and the 3rd light-emitting structure, which face each other on one side of the 3-1 buffer structure (7115). In addition, when the 3rd light-emitting unit (7000) is arranged on the upper side of the 2nd light-emitting unit (6000), the 3-1 opening (7211) may be formed so that at least a portion thereof is located on the upper side of the 2-1 opening (6211) or the upper side of the 2-1 metal layer (6301). In addition, the 3-1 opening (7211) may be formed so as to expose a portion of one side surface of the 3-1 semiconductor layer (7101), as illustrated in FIG. 61.

[0391] The 3-2 opening (7212) may be formed between the side surfaces of the 3-1 semiconductor layer (7101) facing each other on one side of the 3-3 buffer structure (7117). In addition, when the 3rd light-emitting portion (7000) is arranged on the upper side of the 2nd light-emitting portion (6000), the 3-2 opening (7212) may be formed so that at least a portion thereof is located on the upper side of the 2-2 opening (6212) or the upper side of the 2-2 metal layer (6302).

[0392] The 3-3 opening (7213) may be positioned between one side of the 3-2 buffer structure (7116) and one side of the 3-3 light-emitting structure (7111), which face each other on one side of the 3-2 buffer structure (7116). In addition, when the 3rd light-emitting unit (7000) is positioned on the upper side of the 2nd light-emitting unit (6000), the 3-3 opening (7213) may be formed so that at least a portion thereof is positioned on the upper side of the 2-3 opening (6213) or the upper side of the 2-3 metal layer (6303).

[0393] In this way, the 3-1 to 3-3 openings (7211, 7212, 7213) can be formed in an area where the third semiconductor structures are not formed to expose the upper surface of the third base (1310).

[0394] The 3-4 opening (7214) may be located on the upper portion of the third ohmic electrode (7104) of the third light-emitting structure (7111). Accordingly, the 3-4 opening (7214) may be formed to expose the upper surface of the third ohmic electrode (7104) of the third light-emitting structure (7111). In addition, when the third light-emitting unit (7000) is arranged on the upper portion of the first light-emitting unit (5000) and the second light-emitting unit (6000), the 3-4 opening (7214) may be located on the upper portion of the 1-3 buffer structure (5117) and the 2-2 buffer structure (6116).

[0395] Referring to FIG. 62, a third metal layer (7300) may be formed. The third metal layer (7300) may be formed to fill the third opening (7210) of the third insulating layer (7200).

[0396] The third metal layer (7300) may be formed of a conductive material. For example, the third metal layer (7300) may be formed of at least one metal. Additionally, the third metal layer (7300) may be formed as a single layer or multiple layers.

[0397] The third metal layer (7300) may include a third-first metal layer (7301), a third-second metal layer (7302), a third-third metal layer (7303), and a third-fourth metal layer (7304).

[0398] The 3-1 metal layer (7301) may be formed to fill the 3-1 opening (7211). At this time, since the 3-1 opening (7211) exposes a portion of one side of the 3-1 semiconductor layer (7101), the 3-1 metal layer (7301) may be in contact with the 3-1 semiconductor layer (7101). That is, the 3-1 metal layer (7301) may be electrically connected to the 3-1 semiconductor layer (7101). In addition, the 3-1 metal layer (7301) may be formed to further cover the upper surface of the third insulating layer (7200) adjacent to the 3-1 opening (7211). That is, the cross-sectional area or width of the upper surface of the 3-1 metal layer (7301) may be larger than the cross-sectional area or width of the 3-1 opening (7211).

[0399] The third-second metal layer (7302) may be formed to fill the third-second opening (7212). In addition, the third-second metal layer (7302) may be formed to further cover the upper surface of the third insulating layer (7200) adjacent to the third-second opening (7212). That is, the cross-sectional area or width of the upper surface of the third-second metal layer (7302) may be larger than the cross-sectional area or width of the third-second opening (7212).

[0400] The 3-3 metal layer (7303) may be formed to fill the 3-3 opening (7213). In addition, the 3-3 metal layer (7303) may be formed to further cover the upper surface of the third insulating layer (7200) adjacent to the 3-3 opening (7213). Accordingly, the cross-sectional area or width of the upper surface of the 3-3 metal layer (7303) may be larger than the cross-sectional area or width of the 3-3 opening (7213).

[0401] The 3-4 metal layer (7304) may be formed to fill the 3-4 opening (7214). At this time, the 3-4 metal layer (7304) may be in contact with the third ohmic electrode (7104). Therefore, the 3-4 metal layer (7304) may be electrically connected to the third ohmic electrode (7104) and the 3-2 semiconductor layer (7103). In addition, the 3-4 metal layer (7304) may be formed to further cover the upper surface of the third insulating layer (7200) adjacent to the 3-4 opening (7214). That is, the cross-sectional area or width of the upper surface of the 3-4 metal layer (7304) may be larger than the cross-sectional area or width of the 3-4 opening (7214).

[0402] When electricity is supplied through the 3-1 metal layer (7301) connected to the 3-1 semiconductor layer (7101) and the 3-4 metal layer (7304) connected to the 3rd light-emitting structure (7111), light can be emitted from the 3rd light-emitting structure (7111). However, since no current flow is formed in the 3rd buffer structure (7112), the 3rd buffer structure (7112) can maintain a non-light-emitting state even when electricity is supplied to the 3rd light-emitting unit (7000).

[0403] In this way, when the first to third light-emitting parts (5000, 6000, 7000) are individually formed, the second light-emitting part (6000) and the third light-emitting part (7000) can be laminated on top of the first light-emitting part (5000) to form a pixel element (5001).

[0404] Referring to FIG. 63, a first transparent layer (8100) can be formed on the upper portion of the first light-emitting portion (5000).

[0405] The first transparent layer (8100) can be formed to cover the first light-emitting portion (5000) and the first metal layer (5300).

[0406] The first transparent layer (8100) may be formed of an insulating, light-transmitting material. For example, the first transparent layer (8100) may be formed of the same material as the first insulating layer (5200). In addition, the first transparent layer (8100) may have adhesive strength. Therefore, when the second light-emitting unit (6000) is later laminated on the first light-emitting unit (5000), the second light-emitting unit (6000) may be fixed to the first light-emitting unit (5000) by the adhesive strength of the first transparent layer (8100).

[0407] The first transparent layer (8100) can be formed to have a flat upper surface.

[0408] Conventional pixel elements form light-emitting structures only in the light-emitting region, and do not form light-emitting structures in non-light-emitting regions that are not light-emitting regions. In other words, the non-light-emitting region of a conventional pixel element may be a region in which a structure having a lower height than the light-emitting region in which the light-emitting structure is formed is positioned, or in which the structure is omitted. Therefore, when forming a transparent layer covering the upper surface of one light-emitting region in order to laminate another light-emitting region on top of one light-emitting region, it is difficult to form a flat upper surface of the transparent layer due to the height difference between the structures in the non-light-emitting region and the light-emitting region. For example, the upper surface of the transparent layer may be positioned higher than the upper surface of the portion located in the light-emitting region. In this case, when another light-emitting region is laminated on top of the transparent layer covering one light-emitting region, the other light-emitting region may have a part that is not adhered to the transparent layer or a part that is easily peeled off by external impact.

[0409] Referring to FIG. 63, first buffer structures (5112) in an insulating state are formed in areas where the first light-emitting structure (5111) and the first metal layer (5300) are not arranged. In addition, the first buffer structures (5112) are formed to have the same or similar height as the first light-emitting structure (5111). That is, in the first light-emitting portion (5000) of the present embodiment, the first light-emitting structure (5111) is formed in the light-emitting area, and the first buffer structures (5112) having a similar height to the first light-emitting structure (5111) are dispersedly arranged in the non-light-emitting area. Therefore, the first light-emitting portion (5000) has a structure in which structures having similar heights are dispersedly arranged throughout the entire area.

[0410] Accordingly, the first transparent layer (8100) formed on the upper surface of the first light-emitting portion (5000) can be easily formed to have a flat upper surface by the first buffer structures (5112) with the same height or a minimum height difference between the light-emitting region and the non-light-emitting region. Accordingly, when the second light-emitting portion (6000) is later laminated on the upper surface of the first transparent layer (8100), the second light-emitting portion (6000) can be prevented from tilting, thereby enabling stable lamination and adhesion.

[0411] After forming a first transparent layer (8100) on top of the first light-emitting portion (5000), a fourth opening (8110) can be formed in the first transparent layer (8100). The fourth opening (8110) can include a 4-1 opening (8111) and a 4-2 opening (8112).

[0412] The 4-1 opening (8111) may be formed on the upper portion of the 1-1 metal layer (5301) to expose at least a portion of the upper surface of the 1-1 metal layer (5301). At this time, the 4-1 opening (8111) may be formed to include an area where the 1-1 metal layer (5301) and the 2-1 metal layer (6301) overlap with respect to the vertical line when the second light-emitting portion (6000) is laminated on the first light-emitting portion (5000).

[0413] In addition, the 4-2 opening (8112) may be formed on the upper portion of the 1-2 metal layer (5302) to expose at least a portion of the upper surface of the 1-2 metal layer (5302). At this time, the 4-2 opening (8112) may be formed to include an area where the 1-2 metal layer (5302) and the 2-2 metal layer (6302) overlap with respect to the vertical line when the 2nd light-emitting portion (6000) is laminated on the 1st light-emitting portion (5000).

[0414] Referring to FIG. 64, a first connection metal layer (9100) may be formed to fill the fourth opening (8110) of the first transparent layer (8100). The first connection metal layer (9100) may include a first-first connection metal layer (9110) and a first-second connection metal layer (9120).

[0415] The first-first connection metal layer (9110) may be formed to fill the fourth-first opening (8111). At this time, the lower surface of the first-first connection metal layer (9110) may be in contact with the upper surface of the first-first metal layer (5301), and the upper surface may be positioned on the same line as the upper surface of the first transparent layer (8100).

[0416] Additionally, the first-second connection metal layer (9120) may be formed to fill the fourth-second opening (8112). At this time, the lower surface of the first-second connection metal layer (9120) may be in contact with the upper surface of the first-second metal layer (5302), and the upper surface may be positioned on the same line as the upper surface of the first transparent layer (8100).

[0417] The first connection metal layer (9100) may be formed of a conductive material. For example, the first connection metal layer (9100) may be formed of at least one metal. Alternatively, the first connection metal layer (9100) may be formed of a conductive paste. Furthermore, the first connection metal layer (9100) may be formed as a single layer or multiple layers.

[0418] Referring to FIG. 65, the second base (1210) located at the bottom of the second light emitting portion (6000) can be removed.

[0419] Referring to FIG. 66, a second light emitting portion (6000) can be laminated on top of a first light emitting portion (5000).

[0420] The second light-emitting portion (6000) can be laminated on the upper surface of the first transparent layer (8100) formed on the upper surface of the first light-emitting portion (5000). The upper surface of the first transparent layer (8100) has a flat structure. In addition, the upper surface of the first connection metal layer (9100) exposed on the upper surface of the first transparent layer (8100) is also positioned on the same line as the upper surface of the first transparent layer (8100). Therefore, the second light-emitting portion (6000) can be stably laminated on the flat surface formed by the first transparent layer (8100) and the first connection metal layer (9100).

[0421] Additionally, the second light-emitting portion (6000) can maintain a structure laminated on top of the first light-emitting portion (5000) by the adhesive force of the first transparent layer (8100).

[0422] When the second light-emitting portion (6000) is laminated on top of the first light-emitting portion (5000), part or all of the upper surface of the 1-1 connection metal layer (9110) can come into contact with the lower surface of the 2-1 metal layer (6301) of the second light-emitting portion (6000). Accordingly, the 1-1 metal layer (5301) of the first light-emitting portion (5000) and the 2-1 metal layer (6301) of the second light-emitting portion (6000) can be electrically connected to each other by the 1-1 connection metal layer (9110).

[0423] Additionally, a part or all of the upper surface of the first-second connection metal layer (9120) may be in contact with the lower surface of the second-second metal layer (6302) of the second light-emitting portion (6000). Accordingly, the first-second metal layer (5302) of the first light-emitting portion (5000) and the second-second metal layer (6302) of the second light-emitting portion (6000) may be electrically connected to each other by the first-second connection metal layer (9120).

[0424] Referring to FIG. 67, a second transparent layer (8200) can be formed on top of the second light-emitting portion (6000).

[0425] The second transparent layer (8200) may be formed to cover the second light-emitting portion (6000) and the second metal layer (6300). At this time, the second transparent layer (8200) may be formed to have a flat upper surface.

[0426] The second transparent layer (8200) may be formed of an insulating, light-transmitting material. For example, the second transparent layer (8200) may be formed of the same material as the second insulating layer (6200). In addition, the second transparent layer (8200) may have adhesive strength. Therefore, when the third light-emitting unit (7000) is later laminated on the second light-emitting unit (6000), the third light-emitting unit (7000) may be fixed to the second light-emitting unit (6000) by the adhesive strength of the second transparent layer (8200).

[0427] According to the present embodiment, a second light-emitting structure (6111) is arranged in the light-emitting area of ​​the second light-emitting unit (6000), and a second buffer structure (6112) is distributed in the non-light-emitting area. Therefore, the second light-emitting unit (6000) has a structure in which structures of similar heights are distributed in the entire area. When the second transparent layer (8200) is formed to cover the second light-emitting unit (6000), the non-light-emitting area can also be formed to have a similar height to the light-emitting area by the second buffer structure (6112). In other words, it can be easy to form the second transparent layer (8200) to have a flat upper surface by the second buffer structure (6112).

[0428] After forming a second transparent layer (8200) on top of the second light-emitting portion (6000), a fifth opening (8120) can be formed in the second transparent layer (8200). The fifth opening (8120) can include a 5-1 opening (8121), a 5-2 opening (8122), and a 5-2 opening (8122).

[0429] The 5-1 opening (8121) may be formed on the upper portion of the 2-1 metal layer (6301) to expose at least a portion of the upper surface of the 2-1 metal layer (6301). At this time, the 5-1 opening (8121) may be formed to include an area where the 2-1 metal layer (6301) and the 3-1 metal layer (7301) overlap with each other on a vertical line when the 3rd light-emitting portion (7000) is laminated on the 2nd light-emitting portion (6000).

[0430] In addition, the 5-2 opening (8122) may be formed on the upper portion of the 2-2 metal layer (6302) to expose at least a portion of the upper surface of the 2-2 metal layer (6302). At this time, the 5-2 opening (8122) may be formed to include an area where the 2-2 metal layer (6302) and the 3-2 metal layer (7302) overlap with respect to the vertical line when the 3rd light-emitting portion (7000) is laminated on the 2nd light-emitting portion (6000).

[0431] In addition, the 5-3 opening (8123) may be formed on the upper portion of the 2-3 metal layer (6303) to expose at least a portion of the upper surface of the 2-3 metal layer (6303). At this time, the 5-3 opening (8123) may be formed to include an area where the 2-3 metal layer (6303) and the 3-3 metal layer (7303) overlap with respect to the vertical line when the 3rd light-emitting portion (7000) is laminated on the 2nd light-emitting portion (6000).

[0432] Referring to FIG. 68, a second connecting metal layer (9200) can be formed to fill the fifth opening (8120) of the second transparent layer (8200).

[0433] The second connection metal layer (9200) may include a second-first connection metal layer (9210), a second-second connection metal layer (9220), and a second-third connection metal layer (9230).

[0434] The 2-1 connecting metal layer (9210) may be formed to fill the 5-1 opening (8121). At this time, the lower surface of the 2-1 connecting metal layer (9210) may be in contact with the upper surface of the 2-1 metal layer (6301), and the upper surface may be positioned on the same line as the upper surface of the second transparent layer (8200).

[0435] Additionally, the 2-2 connecting metal layer (9220) may be formed to fill the 5-2 opening (8122). At this time, the lower surface of the 2-2 connecting metal layer (9220) may be in contact with the upper surface of the 2-2 metal layer (6302), and the upper surface may be positioned on the same line as the upper surface of the second transparent layer (8200).

[0436] Additionally, the 2-3 connecting metal layer (9230) may be formed to fill the 5-3 opening (8123). At this time, the lower surface of the 2-3 connecting metal layer (9230) may be in contact with the upper surface of the 2-3 metal layer (6303), and the upper surface may be positioned on the same line as the upper surface of the second transparent layer (8200).

[0437] The second connection metal layer (9200) may be formed of a conductive material. For example, the second connection metal layer (9200) may be formed of at least one metal. Alternatively, the second connection metal layer (9200) may be formed of a conductive paste. Furthermore, the second connection metal layer (9200) may be formed as a single layer or multiple layers.

[0438] Referring to FIG. 69, the third base (1310) located at the bottom of the third light-emitting unit (7000) can be removed.

[0439] Referring to FIG. 70, a third light emitting portion (7000) can be laminated on top of a second light emitting portion (6000).

[0440] The third light-emitting portion (7000) can be laminated on the upper surface of the second transparent layer (8200) formed on the upper surface of the second light-emitting portion (6000). The upper surface of the second transparent layer (8200) has a flat structure. In addition, the upper surface of the second connection metal layer (9200) exposed on the upper surface of the second transparent layer (8200) is also positioned on the same line as the upper surface of the second transparent layer (8200). Therefore, the third light-emitting portion (7000) can be stably laminated on the flat surface formed by the second transparent layer (8200) and the second connection metal layer (9200).

[0441] Additionally, the third light-emitting portion (7000) can maintain a structure laminated on top of the second light-emitting portion (6000) by the adhesive force of the second transparent layer (8200).

[0442] When the third light-emitting portion (7000) is laminated on top of the second light-emitting portion (6000), part or all of the upper surface of the second-first connection metal layer (9210) can come into contact with the lower surface of the third-first metal layer (7301) of the third light-emitting portion (7000). Accordingly, the second-first metal layer (6301) of the second light-emitting portion (6000) and the third-first metal layer (7301) of the third light-emitting portion (7000) can be electrically connected to each other by the second-first connection metal layer (9210).

[0443] Additionally, a part or all of the upper surface of the 2-2 connection metal layer (9220) may be in contact with the lower surface of the 3-2 metal layer (7302) of the 3rd light-emitting portion (7000). Accordingly, the 2-2 metal layer (6302) of the 2nd light-emitting portion (6000) and the 3-2 metal layer (7302) of the 3rd light-emitting portion (7000) may be electrically connected to each other by the 2-2 connection metal layer (9220).

[0444] In addition, the 2-3 connection metal layer (9230) may partially or entirely contact the lower surface of the 3-3 metal layer (7303) of the 3rd light-emitting portion (7000). Accordingly, the 2-3 metal layer (6303) of the 2nd light-emitting portion (6000) and the 3-2 metal layer (7302) of the 3rd light-emitting portion (7000) may be electrically connected to each other by the 2-3 connection metal layer (9230).

[0445] In this way, a pixel element (5001) according to the fifth embodiment of the present invention can be formed through the sequence of FIGS. 48 to 71.

[0446] Referring to FIG. 70, the 1-1 metal layer (5301) may be electrically connected to the 1-1 semiconductor layer (5101), the 2-1 metal layer (6301) may be electrically connected to the 2-1 semiconductor layer (6101), and the 3-1 metal layer (7301) may be electrically connected to the 3-1 semiconductor layer (7101). In addition, the 1-1 metal layer (5301), the 2-1 metal layer (6301), and the 3-1 metal layer (7301) may be electrically connected to each other by the 1-1 connection metal layer (9110) and the 2-1 connection metal layer (9210). That is, the 1-1 metal layer (5301), the 2-1 metal layer (6301), the 3-1 metal layer (7301), the 1-1 connection metal layer (9110), and the 2-1 connection metal layer (9210) can be common electrodes of the pixel element (5001). In addition, the upper portion or top surface of the 3-1 metal layer (7301) can be a common electrode pad of the pixel element (5001) that is electrically connected to all of the first semiconductor layers of the first light-emitting portion (5000), the second light-emitting portion (6000), and the third light-emitting portion (7000).

[0447] The first-second metal layer (5302) of the first light-emitting portion (5000), which is electrically connected to the first-second semiconductor layer (5103) through the first ohmic electrode (5104), is electrically connected to the second-second metal layer (6302) of the second light-emitting portion (6000) through the first-second connection metal layer (9120), and the second-second metal layer (6302) is electrically connected to the third-second metal layer (7302) through the second-second connection metal layer (9220). At this time, the second-second metal layer (6302) is insulated from the second light-emitting portion (6000), and the third-second metal layer (7302) is insulated from the third light-emitting portion (7000). Ultimately, the 2nd-2 electrode, the 3rd-2 metal layer (7302), the 1st-2 connection metal layer (9120), and the 2nd-2 connection metal layer (9220) can be electrically connected to the 1st-2 semiconductor layer (5103) of the first light-emitting unit (5000) to serve as electrodes for operating the first light-emitting unit (5000). In addition, the upper portion or top surface of the 3rd-2 metal layer (7302) can serve as an electrode pad to which electricity is applied for operating the first light-emitting unit (5000). Therefore, when electricity is supplied to the pixel element (5001) through the 3rd-2 metal layer (7302), the first light-emitting unit (5000) can operate to emit green light or blue light.

[0448] The 2-3 metal layer (6303) of the second light-emitting portion (6000), which is electrically connected to the 2-2 semiconductor layer (6103) through the 2-0 ohmic electrode (6104), is electrically connected to the 3-3 metal layer (7303) of the 3rd light-emitting portion (7000) through the 2-3 connection metal layer (9230). At this time, the 3-3 metal layer (7303) is insulated from the 3rd light-emitting portion (7000). That is, the 2-3 metal layer (6303), the 3-3 metal layer (7303), and the 2-3 connection metal layer (9230) are electrically connected to the 2-2 semiconductor layer (6103) of the 2nd light-emitting portion (6000) and can serve as electrodes for operating the 2nd light-emitting portion (6000). Additionally, the upper or upper surface of the 3-3 metal layer (7303) can be an electrode pad to which electricity is applied to operate the second light-emitting unit (6000). Accordingly, when electricity is supplied to the pixel element (5001) through the 3-3 metal layer (7303), the second light-emitting unit (6000) can operate to emit blue light or green light.

[0449] The 3-4 metal layer (7304) of the 3rd light-emitting unit (7000) electrically connected to the 3-2 semiconductor layer (7103) through the 3rd ohmic electrode (7104) can be an electrode for operating the 3rd light-emitting unit (7000). In addition, the upper portion or top surface of the 3-4 metal layer (7304) can be an electrode pad to which electricity is applied for operating the 3rd light-emitting unit (7000). Therefore, when electricity is supplied to the pixel element (5001) through the 3-4 metal layer (7304), the 3rd light-emitting unit (7000) can operate and emit red light.

[0450] Also, referring to FIG. 70, the pixel element (5001) may have a first light-emitting structure (5111), a second light-emitting structure (6111), and a third light-emitting structure (7111) all stacked in the central region. Also, the first buffer structure (5112), the second buffer structure (6112), and the third buffer structure (7112) are arranged in an outer region of the central region where the first light-emitting structure (5111), the second light-emitting structure (6111), and the third light-emitting structure (7111) are all stacked.

[0451] The pixel element (5001) according to the present embodiment can form a flat component, such as a transparent layer formed between each light-emitting portion, by additionally forming a buffer structure in a non-light-emitting region. Accordingly, the upper surface of the transparent layer can be formed flat, thereby preventing peeling between the light-emitting portion located above it and the transparent layer. In other words, peeling between the components constituting the pixel element (5001) can be prevented. In addition, the buffer structure can prevent the light-emitting portion located below from bending due to the weight of the light-emitting portion located above. In other words, warping of the pixel element (5001) can be prevented. In this way, the pixel element (5001) according to the present embodiment can prevent deformation of the pixel element (5001) by the buffer structure, thereby improving the reliability of the pixel element (5001).

[0452] Referring to FIG. 71, a protective layer (8300) can be additionally formed on the upper portion of the third light-emitting portion (7000).

[0453] The protective layer (8300) may be formed to cover the third insulating layer (7200) of the third light-emitting portion (7000). In addition, the protective layer (8300) may be formed to cover the side surface of the third metal layer (7300) and expose the upper surface of the third metal layer (7300) to the outside. The third metal layer (7300) exposed to the outside may be a portion electrically connected to an external device.

[0454] The protective layer (8300) may be formed of an insulating material. Furthermore, the protective layer (8300) may be formed of an insulating material that reflects light or an insulating material that includes a light-reflecting material. However, the protective layer (8300) is not necessarily formed of a light-reflecting material, and may be formed of a light-transmitting material, as needed.

[0455] The number of the first buffer structure (5112), the second buffer structure (6112), and the third buffer structure (7112) arranged on each plane may be different. Alternatively, the number of the first buffer structure (5112), the second buffer structure (6112), or the third buffer structure (7112) arranged on at least two different planes may be the same or different. The number of the first buffer structure (5112) and the second buffer structure (6112) may be the same or different, the number of the first buffer structure (5112) and the third buffer structure (7112) may be the same or different, and the number of the second buffer structure (6112) and the third buffer structure (7112) may be the same or different.

[0456] The first buffer structure (5112), the second buffer structure (6112), or the third buffer structure (7112) may be surrounded by an insulating material.

[0457] As described above, the detailed description of the present invention has been made by way of embodiments with reference to the attached drawings. However, the above-described embodiments have only been described as preferred examples of the present invention, and therefore, the present invention should not be understood as being limited to the above-described embodiments, and the scope of the rights of the present invention should be understood by the claims described below and their equivalent concepts.

[0458] As described above, the detailed description of the present invention has been made by way of embodiments with reference to the attached drawings. However, the above-described embodiments have only been described as preferred examples of the present invention, and therefore, the present invention should not be understood as being limited to the above-described embodiments, and the scope of the rights of the present invention should be understood by the claims described below and their equivalent concepts.

Claims

1. A first light-emitting unit including a first light-emitting structure formed by stacking a first semiconductor layer, a first active layer, and a first semiconductor layer; A second light-emitting portion formed on the first light-emitting portion and including a second light-emitting structure formed by stacking a second-1 semiconductor layer, a second active layer, and a second-2 semiconductor layer; and A third light-emitting portion formed on the second light-emitting portion and including a third light-emitting structure formed by stacking a third-1 semiconductor layer, a third active layer, and a third-2 semiconductor layer; A common electrode electrically connected to the 1-1 semiconductor layer, the 2-1 semiconductor layer, and the 3-1 semiconductor layer; A first electrode electrically connected to the first-second semiconductor layer; A second electrode electrically connected to the second-second semiconductor layer; A third electrode electrically connected to the above 3-2 semiconductor layer; The common electrode, the first electrode, the second electrode, and the third electrode are formed to be spaced apart from each other, A pixel element formed so that the common electrode and the first electrode have a step structure by being formed along one side of the 2-1 semiconductor layer and one side of the 3-1 semiconductor layer.

2. In claim 1, The first light emitting unit, the second light emitting unit, and the third light emitting unit are pixel elements that emit visible light of different colors.

3. In claim 1, A first transparent layer formed between the first light-emitting portion and the second light-emitting portion; and A pixel element further comprising a second transparent layer formed between the second light-emitting portion and the third light-emitting portion.

4. In claim 3, The common electrode penetrates the first transparent layer and the second transparent layer and is electrically connected to the second-first semiconductor layer and the first-first semiconductor layer, The first electrode penetrates the first transparent layer and the second transparent layer and is electrically connected to the first and second semiconductor layers, The second electrode is a pixel element that penetrates the second transparent layer and is electrically connected to the second-second semiconductor layer.

5. In claim 1, The common electrode and the first electrode are pixel elements in which the central axis of the portion formed on the first light-emitting portion, the central axis of the portion formed on the second light-emitting portion, and the central axis of the portion formed on the third light-emitting portion are positioned on different vertical lines.

6. In claim 3, The first light-emitting portion further includes a first insulating layer covering the first light-emitting structure, The second light-emitting portion further includes a second insulating layer covering the second light-emitting structure, A pixel element wherein the third light-emitting portion further includes a third insulating layer covering the third light-emitting structure.

7. In claim 6, The above common electrode is, A first metal layer electrically connected to the first semiconductor layer; A 2-1 metal layer electrically connected to the 2-1 semiconductor layer; and A 3-1 metal layer electrically connected to the 3-1 semiconductor layer; The above 2-1 metal layer is formed from the 1-1 metal layer along the inner surface of the 2-1 semiconductor layer to the upper surface of the 2-1 semiconductor layer, The above 3-1 metal layer is a pixel element formed from the upper surface of the 2-1 metal layer along the inner surface of the 3-1 semiconductor layer to the upper surface of the 3-1 semiconductor layer.

8. In claim 7, The first insulating layer includes a first opening through which the first-first semiconductor layer and the first-first metal layer are connected, The second insulating layer includes a second-third opening through which the first-second semiconductor layer and the second-first metal layer are connected, The third insulating layer includes a third opening through which the third-1 semiconductor layer and the third-1 metal layer are connected, A pixel element in which the 2-3 opening is located on the upper outer side of the 1-1 opening, and the 3-3 opening is located on the upper outer side of the 2-3 opening.

9. In claim 8, A 2-1 opening connecting the 1-1 metal layer and the 2-1 metal layer; and It includes a 3-1 opening where the 2-1 metal layer and the 3-1 metal layer are connected; The above 2-1 opening is located on the upper part of the first insulating layer and is formed by penetrating the first transparent layer and the second insulating layer so as to expose a part of the upper surface of the 1-1 metal layer. The above 3-1 opening is located on the upper part of the second insulating layer, and is a pixel element formed by penetrating the second transparent layer and the third insulating layer so as to expose a part of the upper surface of the 2-1 metal layer.

10. In claim 9, The above 2-1 metal layer is formed to cover the inner surface of the 2-1 opening, but is formed to expose the upper surface of the 1-1 metal layer. A pixel element in which the 3-1 metal layer is formed to cover the inner surface of the 3-1 opening, but is formed to expose the upper surface of the 2-1 metal layer.

11. In claim 9, The above 2-1 metal layer is formed to fill the 2-1 opening, A pixel element in which the above 3-1 metal layer is formed to fill the above 3-1 opening.

12. In claim 6, The above first electrode, A first-second metal layer electrically connected to the first-second semiconductor layer; A 2-2 metal layer formed from the upper surface of the 1-2 metal layer to the upper portion of the 2-2 semiconductor layer along the inner surface of the 2nd light-emitting structure; and A pixel element comprising a 3-2 metal layer formed from the upper surface of the 2-2 metal layer to the upper portion of the 3-2 semiconductor layer along the inner surface of the 3rd light-emitting structure.

13. In claim 12, The first insulating layer includes a first-second opening through which the first-second semiconductor layer and the first-second metal layer are connected, The second insulating layer includes a second-second opening through which the first-second metal layer and the second-second metal layer are connected, The third insulating layer includes a third-second opening through which the second-second metal layer and the third-second metal layer are connected, A pixel element wherein the 2-2 opening is located on the upper outer side of the 1-2 opening, and the 3-2 opening is located on the upper outer side of the 2-2 opening.

14. In claim 13, The above 2-2 opening is located on the upper part of the first insulating layer and is formed by penetrating the first transparent layer and the second insulating layer so as to expose a part of the upper surface of the 1-2 metal layer. The above 3-2 opening is located on the upper part of the second insulating layer, and is a pixel element formed by penetrating the second transparent layer and the third insulating layer so as to expose a part of the upper surface of the 2-2 metal layer.

15. In claim 14, The above 2-2 metal layer is formed to fill the 2-2 opening, A pixel element in which the above 3-2 metal layer is formed to fill the above 3-2 opening.

16. In claim 6, The second electrode is, A 2-3 metal layer electrically connected to the 2-2 semiconductor layer; and A pixel element comprising a 3-3 metal layer formed from the upper surface of the 2-3 metal layer to the upper surface of the 3-2 semiconductor layer along the inner surface of the 3rd light-emitting structure.

17. In claim 16, The second insulating layer includes a 2-4 opening that connects the 2-2 semiconductor layer and the 2-3 metal layer, The third insulating layer includes a third-fourth opening through which the second-third metal layer and the third-third metal layer are connected, The above 3-4 opening is a pixel element located on the outer upper side of the above 2-4 opening.

18. In claim 16, The above 3-4 opening is located on the upper part of the second insulating layer, and is a pixel element formed by penetrating the second transparent layer and the third insulating layer so as to expose a part of the upper surface of the 2-3 metal layer.

19. In claim 18, A pixel element in which the 3-3 metal layer is formed to fill the 3-4 opening.

20. In claim 6, A pixel element including a third electrode and a third-fourth metal layer electrically connected to the third-third semiconductor layer.

21. A first light-emitting unit including a first light-emitting structure that emits a first light and a first buffer structure formed to be spaced apart from the first light-emitting structure; A second light-emitting unit including a second light-emitting structure that emits the second light and a second buffer structure formed to be spaced apart from the second light-emitting structure; and A third light-emitting unit including a third light-emitting structure that emits the third light and a third buffer structure formed to be spaced apart from the third light-emitting structure; The second light emitting part is laminated on top of the first light emitting part, and the third light emitting part is laminated on top of the second light emitting part. The first buffer structure, the second buffer structure, and the third buffer structure are non-luminous pixel elements.

22. In claim 21, The first light emitting unit, the second light emitting unit, and the third light emitting unit are pixel elements that emit visible light of different colors.

23. In claim 21, The first light-emitting portion includes a first semiconductor layer, a first semiconductor layer, and a first active layer formed between the first semiconductor layer and the first semiconductor layer. The second light-emitting portion includes a second-first semiconductor layer, a second-second semiconductor layer, and a second active layer formed between the second-first semiconductor layer and the second-second semiconductor layer, The third light-emitting portion is a pixel element including a third active layer formed between the third-1 semiconductor layer, the third-2 semiconductor layer, and the third active layer formed between the third-1 semiconductor layer and the third-2 semiconductor layer.

24. In claim 23, The first light-emitting structure includes the first active layer and the first-second semiconductor layer formed on top of the first-first semiconductor layer, The second light-emitting structure includes the second active layer and the 2-2 semiconductor layer formed on top of the 2-1 semiconductor layer, The third light-emitting structure is a pixel element including the third active layer and the 3-2 semiconductor layer formed on top of the 3-1 semiconductor layer.

25. In claim 23, The first buffer structure includes the first active layer and the first-second semiconductor layer formed on top of the first-first semiconductor layer, The second buffer structure includes the second active layer and the 2-2 semiconductor layer formed on top of the 2-1 semiconductor layer, The third buffer structure is a pixel element including the third active layer and the 3-2 semiconductor layer formed on top of the 3-1 semiconductor layer.

26. In claim 23, A common electrode electrically connected to all of the above 1-1 semiconductor layer, the 2-1 semiconductor layer, and the 3-1 semiconductor layer; A first electrode electrically connected to the first-second semiconductor layer; A second electrode electrically connected to the second-second semiconductor layer; and A pixel element comprising a third electrode electrically connected to the third-second semiconductor layer.

27. In claim 26, A first transparent layer disposed between the first light-emitting portion and the second light-emitting portion; and A pixel element comprising a second transparent layer disposed between the second light-emitting portion and the third light-emitting portion.

28. In claim 27, The common electrode penetrates the first transparent layer and the second transparent layer and is electrically connected to the first-first semiconductor layer and the second-first semiconductor layer, The first electrode penetrates the first transparent layer and the second transparent layer and is electrically connected to the first and second semiconductor layers, The second electrode is a pixel element that penetrates the second transparent layer and is electrically connected to the second-second semiconductor layer.

29. In claim 28, The above common electrode is, A 1-1 metal layer formed on the upper portion of the 1-1 semiconductor layer of the first light-emitting portion and in contact with the 1-1 semiconductor layer; A first-first connecting metal layer penetrating the first transparent layer and in contact with the first-first metal layer; A 2-1 metal layer penetrating the 2-1 semiconductor layer of the 2nd light-emitting portion and contacting the 2-1 semiconductor layer; A second-first connecting metal layer penetrating the second transparent layer and in contact with the second-first metal layer; and A 3-1 metal layer penetrating the 3-1 semiconductor layer of the 3rd light-emitting portion and contacting the 3-1 semiconductor layer; At least a portion of the above 1-1 connecting metal layer is located on top of the above 1-1 metal layer, At least a portion of the above 2-1 metal layer is located on top of the above 1-1 connecting metal layer, At least a portion of the above 2-1 connecting metal layer is located on top of the above 2-1 metal layer, A pixel element wherein at least a portion of the 3-1 metal layer is positioned on top of the 2-1 connecting metal layer.

30. In claim 28, The above first electrode, A 1-2 metal layer formed on the upper portion of the 1-2 semiconductor layer of the 1st light emitting portion and electrically connected to the 1-2 semiconductor layer; A first-second connecting metal layer penetrating the first transparent layer and in contact with the first-second metal layer; A 2-2 metal layer penetrating the 2-1 semiconductor layer of the 2nd light-emitting portion and insulated from the 2-1 semiconductor layer; A 2-2 connecting metal layer penetrating the 2nd transparent layer and in contact with the 2-2 metal layer; and A 3-2 metal layer penetrating the 3-1 semiconductor layer of the 3rd light-emitting portion and insulated from the 3-1 semiconductor layer; At least a portion of the first-second connecting metal layer is located on top of the first-second metal layer, At least a portion of the above 2-2 metal layer is located on top of the above 1-2 connecting metal layer, At least a portion of the above 2-2 connecting metal layer is located on top of the above 2-2 metal layer, A pixel element wherein at least a portion of the 3-2 metal layer is positioned on top of the 2-2 connecting metal layer.

31. In claim 28, The second electrode is, A 2-3 metal layer formed on the upper portion of the 2-2 semiconductor layer of the 2nd light-emitting portion and electrically connected to the 2-2 semiconductor layer; A 2-3 connecting metal layer penetrating the 2nd transparent layer and in contact with the 2-3 metal layer; and A 3-3 metal layer penetrating the 3-1 semiconductor layer of the 3rd light-emitting portion and insulated from the 3-1 semiconductor layer; At least a portion of the above 2-3 connecting metal layer is located on top of the above 2-3 metal layer, A pixel element wherein at least a portion of the 3-3 metal layer is positioned on top of the 2-3 connecting metal layer.

32. In claim 28, The third electrode is, A pixel element including a 3-4 metal layer formed on the upper portion of the 3-2 semiconductor layer of the 3rd light-emitting portion and electrically connected to the 3-2 semiconductor layer.

33. In claim 21, A portion of the second light-emitting structure is located on top of the first light-emitting structure, A pixel element in which a portion of the third light-emitting structure is positioned on top of the second light-emitting structure.

34. In claim 33, A pixel element in which the first buffer structure, the second buffer structure, and the third buffer structure are formed in an outer region of an area in which the first light-emitting structure, the second light-emitting structure, and the third light-emitting structure are all laminated.

35. In claim 26, A pixel element in which the common electrode, the first electrode, the second electrode, and the third electrode are formed in an outer region of an area in which the first light-emitting structure, the second light-emitting structure, and the third light-emitting structure are all laminated.

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