Display device and manufacturing method thereof

Abstract

The invention provides a display device and a manufacturing method thereof. The display device includes: a light emitting structure including a first light emitting element, a second light emitting element, and a third light emitting element; a first electrode pattern electrically connected to the p-type semiconductor layer of the first light emitting element, the p-type semiconductor layer of the second light emitting element, and the p-type semiconductor layer of the third light emitting element; and a second electrode pattern electrically connected to the n-type semiconductor layer of the first light emitting element, the n-type semiconductor layer of the second light emitting element, and the n-type semiconductor layer of the third light emitting element.

Description

TECHNICAL FIELD

[0001] Embodiments of the disclosure relate to a light emitting device, a display apparatus including the light emitting device, and a method of manufacturing the light emitting device and the display apparatus. BACKGROUND

[0002] Light emitting diodes (LEDs) are considered to be next-generation light sources due to their advantages, such as a relatively long lifespan, low power consumption, fast response speed, and environmental friendliness, compared to conventional light sources. Due to these advantages, industrial demand for LEDs is increasing. LEDs have been widely applied and used in various products, such as lighting apparatuses and backlights of display apparatuses. Recently, a micro-LED using a micro-unit of a II-VI or III-V compound semiconductor has been developed.

[0003] In addition, a micro-LED display including a micro-LED of a light emitting device directly used as a display pixel has been developed. A method of manufacturing a light emitting element for each sub-pixel and a method of manufacturing a light emitting element for each pixel have been researched. SUMMARY

[0004] One or more embodiments provide a monolithic light emitting device having an epitaxial structure in which a plurality of light emitting elements emitting light of different wavelengths are vertically stacked, a display apparatus including the same, and a method of manufacturing the same.

[0005] One or more embodiments also provide a monolithic light emitting device in which an active area of an active layer is uniformly distributed, a display apparatus including the same, and a method of manufacturing the same.

[0006] Additional aspects will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art by reference to the description, or can be learned by practice of one or more embodiments.

[0007] According to an aspect of one or more embodiments, there is provided a display device including a display layer including a plurality of light emitting devices and a driving layer configured to drive the plurality of light emitting devices, wherein at least one light emitting device of the plurality of light emitting devices includes: a first insulating layer; a light emitting structure including a first light emitting element, a second light emitting element, and a third light emitting element in order and monolithically on the first insulating layer, each of the first light emitting element, the second light emitting element, and the third light emitting element including a p-type semiconductor layer, an active layer, and an n-type semiconductor layer and configured to emit light of different wavelengths; a first electrode pattern including a first electrode, a second electrode, and a third electrode electrically connected to the p-type semiconductor layer of the first light emitting element, the p-type semiconductor layer of the second light emitting element, and the p-type semiconductor layer of the third light emitting element, respectively, the first electrode, the second electrode, and the third electrode being exposed on a surface of the first insulating layer; and a second electrode pattern including a fourth electrode, a fifth electrode, and a sixth electrode electrically connected to the n-type semiconductor layer of the first light emitting element, the n-type semiconductor layer of the second light emitting element, and the n-type semiconductor layer of the third light emitting element, respectively, the fourth electrode, the fifth electrode, and the sixth electrode being exposed on a surface of the third light emitting element.

[0008] The first electrode can penetrate the first insulating layer and contact the p-type semiconductor layer of the first light emitting element, the fourth electrode can penetrate the third light emitting element and the second light emitting element and contact the n-type semiconductor layer of the first light emitting element, and the first light emitting element can be configured to emit first light based on an electrical signal applied to the first electrode and an electrical signal applied to the fourth electrode.

[0009] The second electrode can penetrate the first insulating layer and the first light emitting element and contact the p-type semiconductor layer of the second light emitting element, the fifth electrode can penetrate the third light emitting element and contact the n-type semiconductor layer of the second light emitting element, and the second light emitting element can be configured to emit second light based on an electrical signal applied to the second electrode and an electrical signal applied to the fifth electrode.

[0010] The third electrode can penetrate the first insulating layer, the first light emitting element, and the second light emitting element and contact the p-type semiconductor layer of the third light emitting element, and the sixth electrode can contact a surface of the n-type semiconductor layer of the third light emitting element, and the third light emitting element can be configured to emit third light based on an electrical signal applied to the third electrode and an electrical signal applied to the sixth electrode.

[0011] The first electrode, the second electrode, and the third electrode can not be electrically connected to each other.

[0012] The fourth electrode, the fifth electrode, and the sixth electrode can be electrically connected to each other.

[0013] The sixth electrode can be on a surface of the third light emitting element and contact the fourth electrode and the fifth electrode.

[0014] The light emitting structure can not include a bonding material.

[0015] In each of the first, second, and third light emitting elements, the p-type semiconductor layer, the active layer, and the n-type semiconductor layer can be sequentially on the driving layer.

[0016] A wavelength of light emitted by the first light emitting element can be greater than a wavelength of light emitted by the second light emitting element, and the wavelength of light emitted by the second light emitting element can be greater than a wavelength of light emitted by the third light emitting element.

[0017] The display device can further include an optical layer on the display layer, the optical layer configured to control a travel path of light emitted from the display layer.

[0018] The optical layer can include a plurality of microlenses corresponding one-to-one to the plurality of light emitting devices.

[0019] The display layer can include first and second light emitting devices adjacent to each other among the plurality of light emitting devices, and a pixel separation portion configured to separate the first and second light emitting devices.

[0020] The pixel separation portion can be configured to spatially separate the p-type semiconductor layer of the first light emitting element, the second light emitting element, and the active layer of the third light emitting element included in the first light emitting device from the p-type semiconductor layer of the first light emitting element, the second light emitting element, and the active layer of the third light emitting element included in the second light emitting device.

[0021] The n-type semiconductor layer of the third light emitting element included in the first light emitting device and the n-type semiconductor layer of the third light emitting element included in the second light emitting device can be connected to each other.

[0022] The sixth electrode included in the first light emitting device and the sixth electrode included in the second light emitting device can be connected to each other and on the same plane.

[0023] The display device can further include a reflective layer on at least a partial area of a side surface of the pixel separation portion and a surface of the first light emitting element.

[0024] The display device can further include a second insulating layer filling at least a portion of an inner space of the pixel separation portion and a space between the display layer and the driving layer, wherein the second insulating layer can include at least one of a black matrix material, a resin, and a polymer.

[0025] According to another aspect of one or more embodiments, there is provided a method of manufacturing a display device, the method including: forming a light emitting structure including a first light emitting element, a second light emitting element, and a third light emitting element on a sacrificial layer, each of the first light emitting element, the second light emitting element, and the third light emitting element including a p-type semiconductor layer, an active layer, and an n-type semiconductor layer and configured to emit light of different wavelengths; forming a first insulating layer on a surface of the first light emitting element of the light emitting structure; forming a first electrode pattern including a first electrode, a second electrode, and a third electrode electrically connected to the p-type semiconductor layer of the first light emitting element, the p-type semiconductor layer of the second light emitting element, and the p-type semiconductor layer of the third light emitting element, respectively, and exposed on a surface of the first insulating layer; bonding the first electrode pattern on a driving layer configured to drive the light emitting structure; removing the sacrificial layer from the light emitting structure; and forming a second electrode pattern including a fourth electrode, a fifth electrode, and a sixth electrode electrically connected to the n-type semiconductor layer of the first light emitting element, the n-type semiconductor layer of the second light emitting element, and the n-type semiconductor layer of the third light emitting element, respectively, and exposed on a surface of the third light emitting element.

[0026] The method can further include forming a pixel separation portion configured to separate the light emitting structure into a plurality of pixels. BRIEF DESCRIPTION OF DRAWINGS

[0027] The above and other aspects, features, and advantages of one or more embodiments will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0028] Figure 1 is a cross-sectional view illustrating a light emitting device according to one or more embodiments;

[0029] Figure 2 is a view illustrating a light emitting device including first to third light emitting elements having varying widths according to one or more embodiments;

[0030] Figure 3 is a view illustrating a light emitting device including a first reflective layer according to one or more embodiments;

[0031] Figure 4 is a view illustrating a light emitting device including a fourth insulating layer according to one or more embodiments;

[0032] Figure 5 is a view illustrating a light emitting device including a second reflective layer according to one or more embodiments;

[0033] Figure 6 is a block diagram of a display device including a light emitting device according to one or more embodiments;

[0034] Figure 7 FIG. 1 is a diagram illustrating a portion of a display device including a plurality of light emitting devices according to one or more embodiments;

[0035] Figure 8 FIG. 2 is a diagram illustrating a display device including a pixel separation portion according to one or more embodiments;

[0036] Figure 9 FIG. 3 is a diagram illustrating a display device including an optical layer controlling an optical path according to one or more embodiments;

[0037] Figure 10 FIG. 4 is a diagram illustrating a display device to which a light emitting device is connected according to one or more embodiments;

[0038] Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 FIGS. 5 to 8 are reference diagrams for describing a method of manufacturing a display device according to one or more embodiments;

[0039] Figure 22 FIG. 9 is a diagram illustrating an example in which a display device according to one or more embodiments is applied to a mobile device;

[0040] Figure 23 FIG. 10 is a diagram illustrating an example in which a display device according to one or more embodiments is applied to a vehicle;

[0041] Figure 24 FIG. 11 is a diagram illustrating an example in which a display device according to one or more embodiments is applied to an augmented reality glass or a virtual reality glass;

[0042] Figure 25 FIG. 12 is a diagram illustrating an example in which a display device according to one or more embodiments is applied to a large signboard; and

[0043] Figure 26 FIG. 13 is a diagram illustrating an example in which a display device according to one or more embodiments is applied to a display of a wearable device. DETAILED DESCRIPTION

[0044] ​​​​​​​​​​Reference will now be made in detail embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments can have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely descriptive of aspects and are not meant to limit the scope of the disclosure as described herein. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Expressions such as "at least one of," when preceding the term "comprising," "including," "containing," "characterized by," "having," "including," "carrying," or "wherein," and the like, indicate that the integer or step recited will be considered exhaustive of any and all possible combinations. For example, the term "a, b, and / or c" will be understood to mean "a alone," "b alone," "c alone," "a and b together," "a and c together," "b and c together," or "a, b, and c together." The term "one or more" followed by a list of elements does not exclude additional elements not listed. For example, "one or more of A, B, and C" does not exclude additional elements such as D.

[0045] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. The embodiments described below are only exemplary and various modifications can be made from these embodiments. In the following drawings, like reference numerals refer to the same parts, and the size of each part in the drawings can be exaggerated for the sake of clarity and convenience of description.

[0046] Hereinafter, what is described as "above" or "on" can include what is directly above, below, left, and right in contact, and what is directly above, below, left, and right without contact.

[0047] Terms such as first, second, and the like can be used to describe various components, but are used only for the purpose of distinguishing one component from another. The terms do not limit the differences in the materials or structures of the components.

[0048] Unless otherwise specified, the singular form of a term can include the plural form. Also, when a part "includes" a component, it means that it can further include other components, rather than excluding other components, unless otherwise stated.

[0049] In addition, the terms such as "unit" and "module" described in the specification mean a unit processing at least one function or operation, which can be implemented as hardware or software, or can be implemented as a combination of hardware and software.

[0050] The specific implementation described in the embodiments is an example and is not intended to limit the technical scope in any way. For the sake of brevity of the description, the description of conventional electronic components, control systems, software, and other functional aspects of systems can be omitted. The connection between the elements shown in the drawings or the connection member is a functional connection and / or a physical or circuit connection, and can be replaced in the actual device, or can be represented as additional various functional connections, physical connections, or circuit connections.

[0051] The use of the term "the" and similar specific terms can correspond to both the singular and the plural.

[0052] Unless explicitly described in terms of order, the operations of the method may be performed in an appropriate order. Furthermore, all exemplary terms (e.g., etc.) are used only for the purpose of describing the technical idea in detail, and the scope is not limited by these exemplary or illustrative terms unless restricted by the claims.

[0053] Figure 1 This is a cross-sectional view showing a light-emitting device 100 according to one or more embodiments.

[0054] Reference Figure 1 The light-emitting device 100 according to one or more embodiments may include an inorganic light-emitting diode (LED) and emit light of a specific wavelength depending on the materials included in the light-emitting device 100. The light-emitting device 100 according to one or more embodiments may have minute dimensions. For example, the width W of the light-emitting device 100 in the horizontal direction (X direction and / or Y direction) may be less than or equal to about 50 μm, less than or equal to about 10 μm, less than or equal to about 5 μm, or less than or equal to about 3 μm.

[0055] A light-emitting device 100 according to one or more embodiments may include a light-emitting structure 10, wherein a first light-emitting element 11, a second light-emitting element 12, and a third light-emitting element 13 emitting light of different wavelengths are monolithically stacked. A cross-section (i.e., a transverse cross-section) parallel to the light-emitting structure 10 in the horizontal direction (X and / or Y direction) may be circular, elliptical, and / or polygonal. For example, the transverse cross-section of the light-emitting structure 10 may have a rectangular shape. A cross-section parallel to the light-emitting structure 10 in the vertical direction (e.g., the Z direction) may also have a rectangular shape. For example, the cross-section of the light-emitting structure 10 in the vertical direction may have a rectangular or trapezoidal shape.

[0056] The light-emitting structure 10 may be a structure in which a first light-emitting element 11 emitting light of a first wavelength, a second light-emitting element 12 emitting light of a second wavelength different from the first wavelength, and a third light-emitting element 13 emitting light of a third wavelength different from the first and second wavelengths are stacked in the vertical direction (Z direction) of the light-emitting structure 10. For example, the first light-emitting element 11 may emit red light, the second light-emitting element 12 may emit green light, and the third light-emitting element 13 may emit blue light. As will be described below, the light-emitting structure 10 may be formed by sequentially monolithically growing (forming) the third light-emitting element 13, the second light-emitting element 12, and the first light-emitting element 11 on a sacrificial layer SCL. Therefore, the light-emitting structure 10 may not include a bonding material for connecting adjacent light-emitting elements among the first light-emitting element 11, the second light-emitting element 12, and the third light-emitting element 13.

[0057] The first light emitting element 11 can include a p-type semiconductor layer P1, an active layer A1 disposed on the p-type semiconductor layer P1, and an n-type semiconductor layer N1 disposed on the active layer A1. The p-type semiconductor layer P1, the active layer A1, and the n-type semiconductor layer N1 can have a vertical stack structure.

[0058] The p-type semiconductor layer P1 and the n-type semiconductor layer N1 can include a Group II-VI or Group III-V compound semiconductor material, particularly a nitride semiconductor material. For example, the p-type semiconductor layer P1 and the n-type semiconductor layer N1 can include at least one of indium aluminum gallium nitride (InAlGaN), gallium nitride (GaN), aluminum gallium nitride (AlGaN), indium gallium nitride (InGaN), aluminum nitride (AlN), and indium nitride (InN) as a nitride semiconductor material. The p-type semiconductor layer P1 and the n-type semiconductor layer N1 can be used to provide electrons and holes to the active layer A1. To this end, the p-type semiconductor layer P1 can be doped with a p-type dopant, and the n-type semiconductor layer N1 can be doped with an n-type dopant that is electrically different from the p-type dopant. The n-type semiconductor layer N1 can include silicon (Si), germanium (Ge), tin (Sn), or the like as a dopant, and the p-type semiconductor layer P1 can include magnesium (Mg), zinc (Zn), or the like as a dopant. The n-type semiconductor layer N1 can provide electrons to the active layer A1, and the p-type semiconductor layer P1 can provide holes to the active layer A1.

[0059] The active layer A1 can be disposed between the p-type semiconductor layer P1 and the n-type semiconductor layer N1. The active layer A1 has a quantum well structure in which a quantum well is disposed between barriers. Light can be generated when holes and electrons provided in the p-type semiconductor layer P1 and the n-type semiconductor layer N1 recombine in the quantum well in the active layer A1. The wavelength of light generated from the active layer A1 can be determined according to the band gap of the material constituting the quantum well in the active layer A1. The active layer A1 can have one quantum well, but can have a multiple quantum well (MQW) structure in which a plurality of quantum wells and a plurality of barriers are alternately disposed. The thickness of the active layer A1 in the vertical direction (Z direction) or the number of quantum wells in the active layer A1 can be appropriately selected in consideration of the voltage applied to the first light emitting element 11 and the light emitting efficiency. The active layer A1 can include a Group II-VI or Group III-V compound semiconductor material, particularly a nitride semiconductor material. For example, the active layer A1 can include at least one of InGaN, GaN, AlGaN, and AlInGaN as a nitride semiconductor material.

[0060] When the active layer Al includes indium (In), the wavelength of light emitted by the active layer Al can decrease as the indium content decreases. For example, in an active layer Al including InGaN or AlInGaN, when the indium content in the nitride semiconductor material is about 35 at%, the active layer Al can emit red light of about 630 nm, when the indium content is about 30 at%, the active layer Al can emit yellow light of about 560 nm, when the indium content is about 25 at%, the active layer Al can emit green light of about 520 nm. Further, when the indium content is about 15 at%, the active layer Al can emit blue light of about 450 nm. For example, the active layer Al of the first light emitting element 11 can include an indium content of about 35 at% and emit red light.

[0061] The second light emitting element 12 can be disposed on the first light emitting element 11. Like the first light emitting element 11, the second light emitting element 12 can include a p-type semiconductor layer P2, an active layer A2, and an n-type semiconductor layer N2, and have a vertical stack structure. The p-type semiconductor layer P2 and the n-type semiconductor layer N2 of the second light emitting element 12 can be the same as the p-type semiconductor layer Pl and the n-type semiconductor layer Nl of the first light emitting element 11, respectively. For example, the p-type semiconductor layer P2 and the n-type semiconductor layer N2 of the second light emitting element 12 can include at least one of nitride semiconductor materials of InAlGaN, GaN, AlGaN, InGaN, AlN, and InN.

[0062] The active layer A2 of the second light emitting element 12 can have a composition of a nitride semiconductor material different from that of the active layer Al of the first light emitting element 11. Accordingly, the second light emitting element 12 can emit light of a wavelength band different from that of the first light emitting element 11. The active layer A2 of the second light emitting element 12 can have an indium content lower than that of the active layer Al of the first light emitting element 11. For example, the active layer A2 of the second light emitting element 12 can include an indium content of about 25 at% and emit green light.

[0063] The third light emitting element 13 can be disposed on the second light emitting element 12. Like the first light emitting element 11 and the second light emitting element 12, the third light emitting element 13 can also include a p-type semiconductor layer P3, an active layer A3, and an n-type semiconductor layer N3, and have a vertical stack structure. The p-type semiconductor layer P3 and the n-type semiconductor layer N3 of the third light emitting element 13 can be the same as the p-type semiconductor layer Pl and the n-type semiconductor layer Nl of the first light emitting element 11, respectively, and thus a detailed description thereof will be omitted. The active layer A3 of the third light emitting element 13 can have a composition of a nitride semiconductor material different from that of the active layer Al of the first light emitting element 11. For example, the active layer A3 of the third light emitting element 13 can include an indium content of about 15 at% and emit blue light.

[0064] The widths of the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 can be substantially the same in the horizontal direction (X direction and / or Y direction). Accordingly, the areas of the active layers A1 of the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 can be substantially the same.

[0065] As the size of the light emitting element decreases, the current density applied to the light emitting element can increase. When the current density increases, the light emitting efficiency of the light emitting element can also decrease due to a decrease in external quantum efficiency in the light emitting element. In the light emitting device 100 according to one or more embodiments, since the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 that emit light of different wavelengths are stacked in the vertical direction (i.e., the light emission direction (e.g., the Z direction)), the active layers A1, A2, and A3 of a relatively wide area can be secured. The active layers A1, A2, and A3 of a relatively wide area can decrease the current density applied to the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13, and the decreased current density can increase the external quantum efficiency and increase the light emitting efficiency of the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13.

[0066] The first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 have been described with respect to a minimum configuration required for basic operation, but embodiments are not limited thereto. At least one of the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 can further include various layers for improving performance. For example, a carrier blocking layer and / or a stress relaxation layer can be further provided between the p-type semiconductor layers (P1, P2, and P3) and the active layers (A1, A2, and A3) and between the active layers (A1, A2, and A3) and the n-type semiconductor layers (N1, N2, and N3). Hereinafter, for convenience of description, a minimum configuration required for basic operation of the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 will be described.

[0067] The light emitting device 100 according to one or more embodiments can include a first insulating layer 21 disposed on a lower surface of the light emitting structure 10. The first insulating layer 21 can include silicon oxide (SiO2). In the light emitting structure 10, the first insulating layer 21, the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 are arranged in the vertical direction in this order, and the lower surface of the first insulating layer 21 can be the lower surface of the light emitting structure 10, and the upper surface of the third light emitting element 13 can be the upper surface of the light emitting structure 10.

[0068] The light emitting device 100 according to one or more embodiments can further include one or more holes penetrating a partial area of the light emitting structure 10. For example, a first hole H1 penetrating the first insulating layer 21 from a lower surface of the light emitting structure 10 to expose a p-type semiconductor layer P1 of the first light emitting element 11, a second hole H2 penetrating the first insulating layer 21 and the first light emitting element 11 from the lower surface of the light emitting structure 10 to expose a p-type semiconductor layer P2 of the second light emitting element 12, a third hole H3 penetrating the first insulating layer 21, the first light emitting element 11, and the second light emitting element 12 from the lower surface of the light emitting structure 10 to expose a p-type semiconductor layer P3 of the third light emitting element 13, a fourth hole H4 penetrating the third light emitting element 13 and the second light emitting element 12 from an upper surface of the light emitting structure 10 (an upper surface of the third light emitting element 13) to expose an n-type semiconductor layer N1 of the first light emitting element 11, and a fifth hole H5 penetrating the third light emitting element 13 from the upper surface of the light emitting structure 10 to expose an n-type semiconductor layer N2 of the second light emitting element 12 can be disposed in the light emitting structure 10. The first to fifth holes H1, H2, H3, H4, and H5 can be spaced apart from each other in space.

[0069] Since the second to fifth holes H2, H3, H4, and H5 partially penetrate the active layers A1, A2, and A3 of the light emitting structure 10, the areas of the active layers A1, A2, and A3 can be reduced. The active layer A1 of the first light emitting element 11 can be penetrated by the second hole H2 and the third hole H3, the active layer A2 of the second light emitting element 12 can be penetrated by the third hole H3 and the fourth hole H4, and the active layer A3 of the third light emitting element 13 can be penetrated by the fourth hole H4 and the fifth hole H5. Since the areas of the active layers A1, A2, and A3 of the light emitting structure 10 according to one or more embodiments are almost uniformly removed by the second to fifth holes H2, H3, H4, and H5, it is possible to prevent a considerable portion of a specific active layer from being removed.

[0070] Further, since the active area of the light emitting structure 10 is reduced by the widths of the second to fifth holes H2, H3, H4, and H5, the widths of the second to fifth holes H2, H3, H4, and H5 in the horizontal direction (X direction and / or Y direction) can be relatively small. The width of each of the second to fifth holes H2, H3, H4, and H5 can be equal to or less than 1 / 5 of the width of the light emitting structure 10. For example, the width of each of the second to fifth holes H2, H3, H4, and H5 in the horizontal direction (X direction and / or Y direction) can be less than or equal to about 1 µm or less than or equal to about 0.5 µm.

[0071] The first hole H1 can be spaced apart from the second hole H2 and the third hole H3. The light emitting device 100 according to one or more embodiments can further include a second insulating layer 22 provided on and surrounding side surfaces of holes (i.e., the second to fifth holes H2, H3, H4, and H5) formed inside the light emitting structure 10. The second insulating layer 22 can include a transparent insulating material. For example, the second insulating layer 22 can include SiO2, silicon nitride (SiN), aluminum oxide (Al2O3), or the like.

[0072] The light emitting device 100 according to one or more embodiments can further include a first electrode pattern 30 exposed on a lower surface of the light emitting structure 10 (i.e., a lower surface of the first insulating layer 21) while being electrically and / or physically connected to the p-type semiconductor layers P1, P2, and P3 of the light emitting structure 10, and a second electrode pattern 40 exposed on an upper surface of the light emitting structure 10 (i.e., an upper surface of the third light emitting element 13 or an upper surface of the n-type semiconductor layer N3 of the third light emitting element 13) while being electrically and / or physically connected to the n-type semiconductor layers N1, N2, and N3 of the light emitting structure 10. For example, the first electrode pattern 30 can protrude from a surface of the p-type semiconductor layer P1 of the first light emitting element 11 while being electrically and / or physically connected to the p-type semiconductor layers P1, P2, and P3 of the light emitting structure 10 by using one or more holes. The second electrode pattern 40 can protrude from a surface of the n-type semiconductor layer N3 of the third light emitting element 13 while being electrically and / or physically connected to the n-type semiconductor layers N1, N2, and N3 of the light emitting structure 10 by using one or more holes.

[0073] The first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 can receive a common voltage through one of the first electrode pattern 30 and the second electrode pattern 40, and each can receive an independent driving voltage through the other of the first electrode pattern 30 and the second electrode pattern 40. Since the first electrode pattern 30 is exposed on a lower surface of the light emitting structure 10 and the second electrode pattern 40 is exposed on an upper surface of the light emitting structure 10, the combination of the module for providing a voltage and the electrode pattern can be easily made since the first electrode pattern 30 and the second electrode pattern 40 are formed on different surfaces of the light emitting structure 10.

[0074] The first electrode pattern 30 can include a first electrode 31 electrically and / or physically connected to the p-type semiconductor layer P1 of the first light emitting element 11, a second electrode 32 electrically and / or physically connected to the p-type semiconductor layer P2 of the second light emitting element 12, and a third electrode 33 electrically and / or physically connected to the p-type semiconductor layer P3 of the third light emitting element 13. The first to third electrodes 31, 32, and 33 can each include a conductive via 31a, 32a, and 33a filling the first to third holes H1, H2, and H3, respectively, and a conductive pad 31b, 32b, and 33b extending onto a surface of the first insulating layer 21 while being in contact with the corresponding conductive via 31a, 32a, and 33a. The conductive pads 31b, 32b, and 33b can be spaced apart from each other.

[0075] The second electrode pattern 40 can include a fourth electrode 41 electrically and / or physically connected to the n-type semiconductor layer N1 of the first light emitting element 11, a fifth electrode 42 electrically and / or physically connected to the n-type semiconductor layer N2 of the second light emitting element 12, and a sixth electrode 43 electrically and / or physically connected to the n-type semiconductor layer N3 of the third light emitting element 13. The fourth electrode 41 and the fifth electrode 42 can have a conductive via shape filling the fourth hole H4 and the fifth hole H5, respectively, and the sixth electrode 43 can have a conductive pad shape disposed on the n-type semiconductor layer N3 of the third light emitting element 13.

[0076] The first electrode 31 can be in contact with the p-type semiconductor layer P1 of the first light emitting element 11, and the fourth electrode 41 can penetrate the third light emitting element 13 and the second light emitting element 12 to be in contact with the n-type semiconductor layer N1 of the first light emitting element 11. In other words, the first electrode 31 can be in contact with a surface of the p-type semiconductor layer P1 of the first light emitting element 11 while filling the first hole H1 included in the first insulating layer 21, and can extend onto the first insulating layer 21. The fourth electrode 41 can be in contact with the n-type semiconductor layer N1 of the first light emitting element 11 while filling the fourth hole H4 penetrating the third light emitting element 13 and the second light emitting element 12. The first light emitting element 11 can emit red light in response to an electrical signal applied through the first electrode 31 and the fourth electrode 41.

[0077] The second electrode 32 can penetrate the first light emitting element 11 to contact the p-type semiconductor layer P2 of the second light emitting element 12, and the fifth electrode 42 can penetrate the third light emitting element 13 to contact the n-type semiconductor layer N2 of the second light emitting element 12. For example, the second electrode 32 can contact the p-type semiconductor layer P2 of the second light emitting element 12 while filling the second hole H2 penetrating the first light emitting element 11, and the fifth electrode 42 can contact the n-type semiconductor layer N2 of the second light emitting element 12 while filling the fifth hole H5 penetrating the third light emitting element 13. The second light emitting element 12 can emit green light in response to an electrical signal applied through the second electrode 32 and the fifth electrode 42. For example, the second light can have a shorter wavelength than the wavelength of the first light.

[0078] The third electrode 33 can penetrate the first light emitting element 11 and the second light emitting element 12 to contact the p-type semiconductor layer P3 of the third light emitting element 13, and the sixth electrode 43 can contact the n-type semiconductor layer N3 of the third light emitting element 13. For example, the third electrode 33 can contact the p-type semiconductor layer P3 of the third light emitting element 13 while filling the third hole H3 penetrating the first light emitting element 11 and the second light emitting element 12, and the sixth electrode 43 can contact the n-type semiconductor layer N3 of the third light emitting element 13. The third light emitting element 13 can emit blue light in response to an electrical signal applied through the third electrode 33 and the sixth electrode 43.

[0079] The first electrode 31, the second electrode 32, and the third electrode 33 can not be connected to each other when the first electrode pattern 30 applies independent driving voltages to each of the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13. The fourth electrode 41, the fifth electrode 42, and the sixth electrode 43 can be disposed to be connected to each other when the second electrode pattern 40 applies a common voltage to the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13. For example, the sixth electrode 43 can be disposed on the upper surface of the light emitting structure 10 (that is, on the upper surface of the n-type semiconductor layer N3 of the third light emitting element 13) while contacting the fourth electrode 41 and the fifth electrode 42. However, embodiments are not limited thereto. Even when the second electrode pattern 40 applies a common voltage to the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13, at least one of the fourth electrode 41, the fifth electrode 42, and the sixth electrode 43 can not be connected to the other electrodes thereamong.

[0080] The conductive paths 31a, 32a, and 33a included in the first electrode pattern 30 and the second conductive pattern 40 can include a transparent conductive material. For example, at least one of the conductive paths 31a, 32a, and 33a included in the first electrode pattern 30 and the second conductive pattern 40 can include a conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), and indium tin zinc oxide (ITZO), a conductive polymer such as PEDOT, or the like. As another example, the conductive pads 31b, 32b, and 33b included in the first electrode pattern 30 can include a transparent conductive material or a non-transparent or reflective conductive material. When the conductive pads 31b, 32b, and 33b included in the first electrode pattern 30 include a reflective conductive material, the conductive pads 31b, 32b, and 33b can perform a reflective function. The conductive pads 31b, 32b, and 33b included in the first electrode pattern 30 can include a metallic material, for example, silver (Ag), gold (Au), platinum (Pt), nickel (Ni), chromium (Cr), and / or aluminum (Al), but are not limited thereto.

[0081] It has been described above that the first light emitting element 11 emits red light, the second light emitting element 12 emits green light, and the third light emitting element 13 emits blue light, but the present disclosure is not limited thereto. That is, it has been described above that the first light emitting element 11 emits light of a longer wavelength than the second light emitting element 12, and the third light emitting element 13 emits light of a shorter wavelength than the second light emitting element 12. However, the present disclosure is not limited thereto. The first light emitting element 11 can emit light of a shorter wavelength than the second light emitting element 12, or the third light emitting element 13 can emit light of a longer wavelength than the second light emitting element 12, and the wavelength of light emitted by each of the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 can be determined according to an application example.

[0082] It has been described above that the light emitting device 100 according to one or more embodiments includes three light emitting elements that emit light of different wavelengths, but the present disclosure is not limited thereto. The light emitting device 100 can include two light emitting elements that emit light of different wavelengths, or can include four or more light emitting elements. Alternatively, the light emitting device 100 can emit light in a visible light band, but can also emit light in an invisible light band.

[0083] Figure 2 FIG. 1 is a view showing a light emitting device 100 including first, second, and third light emitting elements 11, 12, and 13 having a constant width according to one or more embodiments. Referring to FIG. 1, the light emitting device 100 includes the first, second, and third light emitting elements 11, 12, and 13, a first electrode pattern 30, and a second conductive pattern 40. Figure 1 and Figure 2 , Figure 2The lower surface and the upper surface of the light emitting structure 10 can have different sizes. For example, the width W1 of the upper surface of the light emitting structure 10 can be greater than the width W2 of the lower surface of the light emitting structure 10. The width W of the light emitting structure 10 in the horizontal direction (X direction and / or Y direction) can gradually increase from the lower surface to the upper surface of the light emitting structure 10. As will be described below, the light emitting structure 10 can be grown and formed in the order of the third light emitting element 13, the second light emitting element 12, and the first light emitting element 11. As the third light emitting element 13, the second light emitting element 12, and the first light emitting element 11 are grown and formed, the width of the third light emitting element 13, the second light emitting element 12, and the first light emitting element 11 in the horizontal direction (X direction and / or Y direction) can gradually decrease.

[0084] Even though the width of the active layer A3 of the third light emitting element 13 in the horizontal direction (X direction and / or Y direction) is greater than the width of the active layer A1 of the first light emitting element 11 in the horizontal direction (X direction and / or Y direction), each of the third light emitting element 13, the second light emitting element 12, and the first light emitting element 11 can need to secure almost uniform active areas. The width of the active layer A3 of the third light emitting element 13 in the horizontal direction (X direction and / or Y direction) can be about 0.9 times or more and about 1.1 times or less of the width of the active layer A1 of the first light emitting element 11 in the horizontal direction (X direction and / or Y direction).

[0085] Figure 3 FIG. 1 is a view illustrating a light emitting device 100b including a first reflective layer 51 according to one or more embodiments. When the light emitting device 100b is compared with the light emitting device 100a of FIG. 1, Figure 1 When compared with Figure 3 Figure 3 The light emitting device 100b can further include a third insulating layer 23 disposed on the first insulating layer 21 and the first electrode pattern 30 and a first reflective layer 51 disposed on the third insulating layer 23 in the lower surface of the light emitting structure 10. The third insulating layer 23 and the first reflective layer 51 can include a hole overlapping the first hole H1, the second hole H2, and the third hole H3 in the vertical direction (Z direction) of the light emitting structure 10. Accordingly, the first electrode 31, the second electrode 32, and the fifth electrode 33 of the first electrode pattern 30 can be exposed to the outside through the hole of the third insulating layer 23 and the first reflective layer 51. Similar to the first insulating layer 21, the third insulating layer 23 can include a transparent insulating material.

[0086] ​The first reflective layer 51 can reflect incident light into the light emitting structure 10. The first reflective layer 51 can reflect incident light into the light emitting structure 10 and emit the incident light to the outside through the upper surface of the light emitting structure 10, thereby increasing the light emission efficiency of light emitted to the upper surface of the light emitting structure 10. The first reflective layer 51 can include a material having a high reflectivity with respect to light. The first reflective layer 51 can include a metal material, for example, Ag, Au, Pt, Ni, Cr, and / or Al, but is not limited thereto. When the conductive pads 31b, 32b, and 33b of the first electrode pattern 30 include a metal having a relatively high reflectivity, light emitted to the lower surface of the light emitting structure 10 can be more effectively reduced. When the conductive pads 31b, 32b, and 33b of the first electrode pattern 30 partially overlap the first reflective layer 51 in the vertical direction (Z direction) of the light emitting structure 10, the reflection efficiency on the lower surface of the light emitting structure 10 can be further increased.

[0087] Figure 4 FIG. 1C is a view illustrating a light emitting device 100c including a fourth insulating layer 24 according to one or more embodiments. Figure 3 When compared with Figure 4 , the light emitting device 100c of Figure 4 may further include a fourth insulating layer 24 provided on the side surface of the light emitting structure 10 and surrounding the side surface of the light emitting structure 10. The fourth insulating layer 24 can be a protective layer that protects the light emitting structure 10 from the outside. Similar to the first insulating layer 21, the fourth insulating layer 24 can include a transparent insulating material. However, embodiments are not limited thereto. The fourth insulating layer 24 can be a black matrix material. Accordingly, the fourth insulating layer 24 can prevent light generated by the light emitting structure 10 from being emitted to the side surface of the light emitting structure 10 or prevent light from being incident on the side surface of the light emitting structure 10 from the outside.

[0088] Figure 5 FIG. 1D is a view illustrating a light emitting device 100d including a second reflective layer 52 according to one or more embodiments. Figure 5 The light emitting device 100d of may further include a second reflective layer 52 provided on the side surface of the light emitting structure 10 and surrounding the side surface of the light emitting structure 10. The second reflective layer 52 can be disposed on the fourth insulating layer 24. The second reflective layer 52 can reflect light traveling to the side surface of the light emitting structure 10 into the inside of the light emitting structure 10. Accordingly, light generated by the light emitting structure 10 can be emitted to the outside through the upper surface of the light emitting structure 10, thereby improving the light emission efficiency in the direction of the upper surface of the light emitting structure 10.

[0089] The light emitting devices 100, 100a, 100b, 100c, and 100d according to one or more embodiments can emit light of a plurality of different wavelengths and thus be used as pixels of a display apparatus. One light emitting device 100, 100a, 100b, 100c, or 100d becomes one pixel, and thus a display apparatus that is relatively small and has a high resolution can be implemented.

[0090] Figure 6 is a block diagram of a display apparatus 200 including a light emitting device according to one or more embodiments. Referring to Figure 6 , the display apparatus 200 can include a pixel array 210, a scan driver 220, a data driver 230, and a processor 240. The pixel array 210 can include a plurality of pixels P arranged in a two-dimensional (2D) array form, a plurality of scan line groups that transmit scan signals to the plurality of pixels P, and a plurality of data line groups that transmit data signals to the plurality of pixels P.

[0091] At least one of the plurality of pixels P of the pixel array 210 can include the above-described light emitting device 100, 100a, 100b, 100c, or 100d. For example, at least one of the plurality of pixels P can include one light emitting device 100, 100a, 100b, 100c, or 100d including a first light emitting element 11 that emits red light, a second light emitting element 12 that emits green light, and a third light emitting element 13 that emits blue light, and a first transistor TR1, a second transistor TR2, and a third transistor TR3 electrically and / or physically connected to the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13, respectively.

[0092] Each scan line group can include a first scan line SL1, a second scan line SL2, and a third scan line SL3 extending in an X direction. The first scan line SL1, the second scan line SL2, and the third scan line SL3 can be connected to the plurality of pixels P arranged in the X direction. For example, the first scan line SL1 can be electrically and / or physically connected to a gate electrode G of the first transistor TR1 in each pixel P, the second scan line SL2 can be electrically and / or physically connected to a gate electrode G of the second transistor TR2 in each pixel P, and the third scan line SL3 can be electrically and / or physically connected to a gate electrode G of the third transistor TR3 in each pixel P. The first scan line SL1, the second scan line SL2, and the third scan line SL3 can also be connected to the scan driver 220 to receive scan signals from the scan driver 220.

[0093] Each data line group can include a first data line DL1, a second data line DL2, and a third data line DL3 extending in the Y direction. The first data line DL1, the second data line DL2, and the third data line DL3 can be connected to a plurality of pixels P arranged in the Y direction. For example, the first data line DL1 can be electrically connected to a source horizontal line SHL of the first transistor TR1 in each pixel P, the second data line DL2 can be electrically connected to a source horizontal line SHL of the second transistor TR2 in each pixel P, and the third data line DL3 can be electrically connected to a source horizontal line SHL of the third transistor TR3 in each pixel P. The first data line DL1, the second data line DL2, and the third data line DL3 can also be connected to the data driver 230 to receive data signals from the data driver 230.

[0094] The processor 240 can control the operations of the scan driver 220 and the data driver 230 based on data of an image to be displayed by the pixel array 210, thereby adjusting the scan signals and the data signals provided to each pixel P.

[0095] Figure 7 FIG. 1 is a diagram illustrating a portion of a display apparatus 200 including a plurality of light emitting devices 311 according to one or more embodiments. Referring to FIG. 1, Figure 7 , the display apparatus 200 can include a display layer 310 including the plurality of light emitting devices 311, a driving layer 320 driving the plurality of light emitting devices 311, and a substrate 330 supporting the driving layer 320. The driving layer 320 and the substrate 330 are collectively referred to as a backplane 301.

[0096] The display layer 310 can include the plurality of light emitting devices 311. At least one of the plurality of light emitting devices 311 can include a first light emitting element 11, a second light emitting element 12, and a third light emitting element 13 emitting light of different wavelengths. From the perspective of the display apparatus 200, the first light emitting element 11 can be a component of a first sub-pixel, the second light emitting element 12 can be a component of a second sub-pixel, and the third light emitting element 13 can be a component of a third sub-pixel. The light emitting device 311 has been described above, and thus a detailed description thereof will be omitted. Figure 1 The light emitting device 100 illustrated is shown in Figure 7 , but embodiments are not limited thereto. The display apparatus 200 can include a light emitting device 100a, 100b, 100c, or 100d illustrated in Figure 2 , Figure 3 , Figure 4 or Figure 5 .

[0097] The substrate 330 can include an insulating material such as, for example, glass, an organic polymer, a crystal, etc. Also, the substrate 330 can include a material having flexibility to be bent or folded, and can have a single layer structure or a multi-layer structure.

[0098] The driving layer 320 can include a buffer layer 321 disposed on the substrate 330 and transistors disposed on the buffer layer 321. The driving layer 320 can further include a driving voltage wiring, the scan driver 220, the data driver 230, and the processor 240, which are not shown in FIG. 1. Figure 7

[0099] The buffer layer 321 can prevent impurities from diffusing into the transistors. The buffer layer 321 can be provided as a single layer, but can be provided as at least a double layer or a multi-layer.

[0100] When the buffer layer 321 is provided as a multi-layer, the multi-layer can include the same material or can include different materials. The buffer layer 321 can be omitted depending on the material of the substrate 330 and process conditions.

[0101] The first to third transistors TR1, TR2, and TR3 can drive the respective light emitting elements included in the display layer 310. For example, the driving layer 320 can include the first transistor TR1 driving the first light emitting element 11, the second transistor TR2 driving the second light emitting element 12, and the third transistor TR3 driving the third light emitting element 13. Each of the first to third transistors TR1, TR2, and TR3 can include a semiconductor layer, a gate electrode, a source electrode, and a drain electrode.

[0102] The semiconductor layer can be disposed on the buffer layer 321. The semiconductor layer can include a source region in contact with the source electrode and a drain region in contact with the drain electrode. A region between the source region and the drain region can be a channel region.

[0103] The semiconductor layer can be a semiconductor pattern including polycrystalline silicon, amorphous silicon, an oxide semiconductor, etc. The channel region is a semiconductor pattern not doped with impurities, and can be an intrinsic semiconductor. The source region and the drain region can be semiconductor patterns doped with impurities.

[0104] The gate electrode can be provided on the semiconductor layer, and a gate insulating layer 322 is disposed between the gate electrode and the semiconductor layer.

[0105] The source electrode and the drain electrode can be in contact with the source region and the drain region of the semiconductor layer, respectively, through contact holes penetrating the interlayer insulating layer 323 and the gate insulating layer 322.

[0106] ​A protective layer 324 can be provided on the first to third transistors TR1, TR2, and TR3. The protective layer 324 can include first to third conductive paths CV1, CV2, and CV3. The first electrode 31 can be electrically connected to the first transistor TR1 (e.g., a drain electrode of the first transistor TR1) through the first conductive path CV1, the second electrode 32 can be electrically connected to the second transistor TR2 (e.g., a drain electrode of the second transistor TR2) through the second conductive path CV2, and the third electrode 33 can be electrically connected to the third transistor TR3 (e.g., a drain electrode of the third transistor TR3) through the third conductive path CV3. Although not shown in FIG. 3, the second electrode pattern 40 can also be connected to the circuit module of the driving layer 320 through a wire. Figure 7

[0107] When a driving voltage is applied through the first electrode pattern 30 and a common voltage is applied through the second electrode pattern 40, each of the first to third light emitting elements 11, 12, and 13 can independently emit light based on the applied voltages.

[0108] Figure 8 FIG. 4 is a diagram illustrating a display device 200a including a pixel separation portion 312 according to one or more embodiments.

[0109] Referring to Figure 7 and Figure 8 , Figure 8 The display device 200a of

[0110] The sixth electrodes 43 included in the adjacent light emitting devices 311 can extend to the upper surfaces of the pixel separation portion 312 to be connected to each other. For example, the sixth electrodes 43 included in the adjacent light emitting devices 311 can be disposed on the same plane. The sixth electrodes 43 included in the plurality of light emitting devices 311 are connected to each other, and thus the number of circuit modules to which a common voltage is applied can be reduced.

[0111] Figure 9 FIG. 5 is a diagram illustrating a display device 200b including an optical layer 340 controlling an optical path according to one or more embodiments.

[0112] Referring to Figure 8 and Figure 9 , Figure 9 ​The display device 200b may include an optical layer 340 disposed on the display layer 310 and may control the path of light emitted from the display layer 310. The optical layer 340 may include a plurality of microlenses 341, each microlens 341 configured to correspond one-to-one with a plurality of light-emitting elements 311. Each microlens 341 can guide light emitted from its corresponding light-emitting element 311 in a specific direction by adjusting the path of light emitted from that element. The microlenses 341 may have different refractive indices and thus focus the light emitted from the display layer 310. Therefore, the display device 200b can generate images with relatively small viewing angles. The optical layer 340 may magnify or reduce the image generated in the display layer 310 depending on the purpose of the display device 200b. Furthermore, the optical layer 340 may prevent the mixing of light emitted from adjacent light-emitting elements 311.

[0113] Figure 10 This is a diagram showing a display device 200c to which a light-emitting device 311 according to one or more embodiments is connected.

[0114] Reference Figure 9 and Figure 10 The n-type semiconductor layer N3 of the third light-emitting element 13 can be Figure 10 The adjacent light-emitting devices 311 of the display device 200c are connected to each other. Pixels PX can be separated by pixel separators 312 that penetrate a portion of the light-emitting structure 10. Pixel separators 312 can be trenches that penetrate the p-type semiconductor layer P3 of the first light-emitting element 11, the second light-emitting element 12, and the third light-emitting element 13, as well as the active layer A3 of the third light-emitting element 13. The trenches can form closed loops, and the shape of the closed loops can be the cross-sectional shape of the pixel PX. For example, from the perspective of the vertical direction (Z direction) of the display layer 310, the cross-sectional shape of the pixel separator 312 can be polygonal, such as a square. When the cross-sectional shape of the pixel separator 312 is polygonal, a higher resolution per unit area can be achieved in the display device 200c compared to a circular or elliptical cross-sectional shape. The width of the pixel separator 312 can be determined by the distance between the pixels PX. A fourth insulating layer 24 and a second reflective layer 52 can be sequentially disposed on the side surface of the pixel separator 312.

[0115] The display layer 320 may further include a contact electrode pattern 313 electrically connecting the first electrode 31, the second electrode 32, and the third electrode 33 to the driving layer 320. The contact electrode pattern 313 may include a first contact electrode 61 electrically connecting the first electrode 31 to the driving layer 320, a second contact electrode 62 electrically connecting the second electrode 32 to the driving layer 320, and a third contact electrode 63 electrically connecting the third electrode 33 to the driving layer 320. The contact electrode pattern 313 may include a conductive material. For example, the contact electrode pattern 313 may be a bonding metal such as Au, tin (Sn), or copper (Cu).

[0116] The display layer 310 can further include a fifth insulating layer 25 filling a remaining space of the pixel partition 312 and a space between the display layer 310 and the driving layer 320. The fifth insulating layer 25 can include at least one of a black matrix material, a resin, and a polymer. As another example, the fifth insulating layer 25 can include a transparent inorganic material such as SiO2.

[0117] Figures 11 to 21 FIG. 10 is a reference diagram for describing a method of manufacturing the display apparatus 200c according to one or more embodiments.

[0118] Referring to FIG. 10, Figure 11 The light emitting structure 10 can be formed on a sacrificial layer SCL. The sacrificial layer SCL can be a layer for growing light emitting devices. The sacrificial layer SCL can include various materials used in general semiconductor processes. For example, a silicon substrate or a sapphire substrate can be used as the sacrificial layer SCL.

[0119] The third light emitting element 13, the second light emitting element 12, and the first light emitting element 11 can be sequentially and vertically formed on the sacrificial layer SCL. For example, an n-type semiconductor layer N3, an active layer A3, and a p-type semiconductor layer P3 of the third light emitting element 13 can be sequentially grown on the sacrificial layer SCL, an n-type semiconductor layer N2, an active layer A2, and a p-type semiconductor layer P2 of the second light emitting element 12 can be sequentially grown on the p-type semiconductor layer P3 of the third light emitting element 13, and an n-type semiconductor layer N1, an active layer A1, and a p-type semiconductor layer P1 of the first light emitting element 11 can be sequentially grown on the p-type semiconductor layer P2 of the second light emitting element 12.

[0120] Among the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13, the lowest indium content can be included in the active layer A3 of the third light emitting element 13, and the highest indium content can be included in the active layer A1 of the first light emitting element 11. In general, the lower the indium content, the higher the growth temperature of a nitride semiconductor, and thus an active layer having a relatively high growth temperature can be grown first, and an active layer having a relatively low growth temperature can be grown later. When an active layer having a higher indium content is grown first and an active layer having a lower indium content is grown later, the active layer having the higher indium content can be deteriorated. The growth order of the light emitting structure 10 according to one or more embodiments can prevent deterioration of the active layer A1 of the first light emitting element 11 having the highest indium content.

[0121] The light emitting structure 10 according to one or more embodiments can not include a bonding material between the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13, because the third light emitting element 13, the second light emitting element 12, and the first light emitting element 11 are sequentially and monolithically formed.

[0122] The light emitting structure 10 can be formed using a method such as, for example, metal organic chemical vapor deposition (MOCVD), chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), molecular beam epitaxy (MBE), hydride vapor phase epitaxy (HVPE), or the like.

[0123] A first insulating layer 21 can be further formed on the light emitting structure 10 (i.e., on the p-type semiconductor layer P1 of the first light emitting element 11). The first insulating layer 21 can be formed by a CVD process.

[0124] Referring to Figure 12 The first hole H1 exposing the p-type semiconductor layer P1 of the first light emitting element 11, the second hole H2 exposing the p-type semiconductor layer P2 of the second light emitting element 12, and the third hole H3 exposing the p-type semiconductor layer P3 of the third light emitting element 13 can be formed in the light emitting structure 10, and a second insulating layer 22 provided on and surrounding side surfaces of the second hole H2 and the third hole H3 can be formed. The second hole H2 can penetrate the first light emitting element 11, and the third hole H3 can penetrate the first light emitting element 11 and the second light emitting element 12. Accordingly, the active area of the first light emitting element 11 and the second light emitting element 12 can be reduced. Accordingly, the width of the second hole H2 and the third hole H3 in the horizontal direction (X direction and / or Y direction) can be small, such as less than or equal to about 1 µm or less than or equal to about 0.5 µm. The second hole H2 and the third hole H3 can be performed by, for example, a plasma etching process. Since the first hole H1 is formed by etching only the first insulating layer 21, an etching process other than the plasma etching process can be applied. For example, the first hole H1 can be formed by dry etching or wet etching.

[0125] The second insulating layer 22 can be formed by, for example, an atomic layer deposition process. Even though the second insulating layer 22 is provided on and surrounding the side surfaces of the second hole H2 and the third hole H3, the p-type semiconductor layer P2 of the second light emitting element 12 and the p-type semiconductor layer P3 of the third light emitting element 13 can still be exposed to the outside.

[0126] Referring to Figure 13The p-type semiconductor properties of the p-type semiconductor layers P2 and P3 exposed to the outside can be restored. As described above, the exposed p-type semiconductor layer P2 of the second light emitting element 12 and the exposed p-type semiconductor layer P3 of the third light emitting element 13 can be damaged in a process of forming the second hole H2 and the third hole H3 by a plasma etching process. Thus, the exposed p-type semiconductor layer P2 of the second light emitting element 12 and the exposed p-type semiconductor layer P3 of the third light emitting element 13 can be damaged and can lose diode junction properties or p-type semiconductor properties.

[0127] The exposed p-type semiconductor layer P2 of the second light emitting element 12 and the exposed p-type semiconductor layer P3 of the third light emitting element 13 can be additionally provided with a p-type dopant or a p-type semiconductor, and thus the lost p-type semiconductor properties can be restored. The region to which the p-type dopant or the p-type semiconductor is additionally provided can be referred to as a p-type semiconductor layer. The process of restoring the p-type semiconductor properties can be performed at a relatively high temperature, for example, greater than or equal to about 800℃, when the light emitting structure 10 is disposed on the sacrificial layer SCL. For example, when the process of restoring the p-type semiconductor properties is performed on the driving layer described below, the device properties of the transistor included in the driving layer can be deteriorated.

[0128] Referring to Figure 14 , the first electrode pattern 30 can be formed on the light emitting structure 10. That is, the first electrode 31 can be formed on the p-type semiconductor layer P1 of the first light emitting element 11 exposed through the first hole H1, the second electrode 32 can be formed on the p-type semiconductor layer P2 of the second light emitting element 12 exposed through the second hole H2, and the third electrode 33 can be formed on the p-type semiconductor layer P3 of the third light emitting element 13 exposed through the third hole H3. The first electrode 31, the second electrode 32, and the third electrode 33 can all be exposed from the surface of the first light emitting element 11 and extend onto the first insulating layer 21. The first electrode 31, the second electrode 32, and the third electrode 33 can be formed not to be connected to each other.

[0129] Referring to Figure 15 , the pixel separation part 312 can be formed in the light emitting structure 10. For example, the pixel separation part 312 can be formed in a trench shape penetrating the p-type semiconductor layers P1 and P3 of the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13, and the active layer A3 of the third light emitting element 13. The width of the pixel separation part 312 can be the distance between the adjacent pixels PX. Figure 15 It is shown that the pixel separation part 312 does not penetrate the n-type semiconductor layer N3 of the third light emitting element 13, but embodiments are not limited thereto. The pixel separation part 312 can penetrate the n-type semiconductor layer N3 of the third light emitting element 13. The pixel separation part 312 does not penetrate the n-type semiconductor layer N3 of the third light emitting element 13, thereby increasing the durability of the display layer 310.

[0130] Referring to Figure 16 , a third insulating layer 23, a fourth insulating layer 24, a first reflective layer 51, a second reflective layer 52, and a fifth insulating layer 25 can be formed on the light emitting structure 10. The third insulating layer 23 and the fourth insulating layer 24 can be formed on the side surfaces of the first electrode pattern 30 and the pixel separation portion 312, respectively, and the first reflective layer 51 and the second reflective layer 52 can be formed on the third insulating layer 23 and the fourth insulating layer 24, respectively. The third insulating layer 23 and the first reflective layer 51 can include holes exposing the first electrode 31, the second electrode 32, and the third electrode 33. The fifth insulating layer 25 can be formed to cover the entire first reflective layer 51 and fill the remaining space of the pixel separation portion 312. The fifth insulating layer 25 can also include holes exposing the first electrode 31, the second electrode 32, and the third electrode 33. The third insulating layer 23 and the fourth insulating layer 24 can each include a transparent insulating material, and the fifth insulating layer 25 can include an insulating material having elasticity. In addition, the first reflective layer 51 and the second reflective layer 52 can each include a metal or the like.

[0131] Referring to Figure 17 , a contact electrode pattern 313 including first, second, and third contact electrodes 61, 62, and 63 in contact with the first, second, and third electrodes 31, 32, and 33 can be formed while filling the holes of the fifth insulating layer 25. The first, second, and third contact electrodes 61, 62, and 63 can each include a conductive material having elasticity.

[0132] Referring to Figure 18 , the contact electrode pattern 313 can be bonded to a back plate 301. The back plate 301 can include first, second, and third transistors TR1, TR2, and TR3 that respectively drive the first, second, and third light emitting elements 11, 12, and 13. First, second, and third electrode pads electrically connected to the first, second, and third transistors TR1, TR2, and TR3, respectively, are provided on a surface of the back plate 301. The back plate 301 can be bonded to the light emitting device 100c such that the first, second, and third electrode pads are connected to the first, second, and third contact electrodes 61, 62, and 63 on a one-to-one basis. The back plate 301 can include various types of circuit modules in addition to the first, second, and third transistors TR1, TR2, and TR3.

[0133] Referring to Figure 19 , the sacrificial layer SCL can be removed from the light emitting structure 10. After bonding the light emitting structure 10 and the back plate 301, the vertical direction of the light emitting structure 10 can be flipped such that the back plate 301 is disposed under the light emitting structure 10. In addition, the sacrificial layer SCL can be removed from the light emitting structure 10.

[0134] Referring to Figure 20 A second electrode pattern 40 can be formed on the light emitting structure 10. First, fourth and fifth holes H4 and H5 exposing the n-type semiconductor layer N1 of the first light emitting element 11 and the n-type semiconductor layer N2 of the second light emitting element 12 can be formed, and a second insulating layer 22 provided on and surrounding side surfaces of the fourth and fifth holes H4 and H5 can be formed. The fourth hole H4 can penetrate the third light emitting element 13 and the second light emitting element 12, and the fifth hole H5 can penetrate the third light emitting element 13, so the area of the active layers A2 and A3 of the second and third light emitting elements 12 and 13 can be reduced. Accordingly, the width of the fourth and fifth holes H4 and H5 in the horizontal direction (X and / or Y direction) can be small, such as less than or equal to about 1 μm or less than or equal to about 0.5 μm.

[0135] The fourth and fifth holes H4 and H5 can be formed by a plasma etching process. Even if the fourth and fifth holes H4 and H5 are formed by the plasma etching process, the exposed n-type semiconductor layers N1 and N2 of the first and second light emitting elements 11 and 12 can maintain n-type semiconductor characteristics. Accordingly, a separate process for restoring n-type semiconductor characteristics can not be needed.

[0136] The second electrode pattern 40 can be formed using the fourth and fifth holes H4 and H5. For example, a third electrode 41 can be formed on the n-type semiconductor layer N1 of the first light emitting element 11 exposed through the fourth hole H4, a fourth electrode 42 can be formed on the n-type semiconductor layer N2 of the second light emitting element 12 exposed through the fifth hole H5, and a sixth electrode 43 can be formed on the exposed n-type semiconductor layer N3 of the third light emitting element 13. The sixth electrode 43 can be disposed on the n-type semiconductor layer N3 of the third light emitting element 13 while being connected to the third and fourth electrodes 41 and 42. The sixth electrode 43 can cover the entire upper surface of the n-type semiconductor layer N3 of the third light emitting element 13.

[0137] The second electrode pattern 40 can be formed on a surface of the light emitting structure 10 different from the surface on which the first electrode pattern 30 is disposed (i.e., the surface of the first light emitting element 11), i.e., the surface of the third light emitting element 13, after the light emitting structure 10 is bonded to the back plate 301. Accordingly, the active areas of the first, second, and third light emitting elements 11, 12, and 13 lost due to the holes can be maintained substantially uniform. In addition, the first and second electrode patterns 30 and 40 can be disposed on different surfaces of the light emitting structure 10, thereby simplifying the connection wiring between the first and second electrode patterns 30 and 40 and the corresponding circuit modules.

[0138] Referring to Figure 21The optical layer 340 can be formed on an upper surface of the light emitting structure 10 (e.g., a surface of the third light emitting element 13). The optical layer 340 can control a travel path of light generated by the light emitting structure 10. The microlens 341 is shown as an optical element in Figure 21 but embodiments are not limited thereto. The optical element can be a microstructure such as a superstructure.

[0139] In the display apparatuses 200, 200a, 200b, and 200c described above, one light emitting element 311 can be used to implement one pixel that provides all of blue light, green light, and red light. Accordingly, the display apparatus 200 can provide an ultra-high resolution image or be implemented as a relatively small display apparatus. The display apparatus 200 can be applied to various electronic devices having a screen display function.

[0140] Figure 22 is a diagram illustrating an example in which a display apparatus according to one or more embodiments is applied to a mobile device 1000. The mobile device 1000 can include a display apparatus 1100. The display apparatus 1100 can include the display apparatus 200, 200a, 200b, or 200c according to one or more embodiments. The display apparatus 1100 can have a foldable structure, e.g., be implemented as a multi-foldable display. For example, the mobile device 1000 has been illustrated as having a foldable display, but can also have a flat display.

[0141] Figure 23 is a diagram illustrating an example in which a display apparatus 1250 according to one or more embodiments is applied to a vehicle. The display apparatus 1250 can be a head-up display apparatus of the vehicle. The head-up display apparatus can include the display apparatus 1250 provided in an area of the vehicle and at least one light path changing member 1200 that changes a light path so that a driver can see an image generated on the display apparatus 1250. The display apparatus 1250 can include the display apparatus 200, 200a, 200b, or 200c according to one or more embodiments.

[0142] Figure 24 is a diagram illustrating an example in which a display apparatus according to one or more embodiments is applied to an augmented reality glasses 1300 or a virtual reality glasses. The augmented reality glasses 1300 can include a projection system 1310 that forms an image and at least one element 1350 that guides the image from the projection system 1310 into an eye of a user. The projection system 1310 can include the display apparatus 200, 200a, 200b, or 200c according to one or more embodiments.

[0143] Figure 25is a view showing an example in which the display apparatus according to one or more embodiments is applied to a relatively large sign 1400. The sign 1400 can be used for outdoor advertising using a digital information display, and can control advertising content through a communication network. The sign 1400 can include the display apparatus 200, 200a, 200b, or 200c according to one or more embodiments.

[0144] Figure 26 is a view showing an example in which the display apparatus according to one or more embodiments is applied to a display 1500 of a wearable device. The display 1500 of the wearable device can include the display apparatus 200, 200a, 200b, and 200c according to one or more embodiments.

[0145] The display apparatus 200, 200a, 200b, and 200c according to one or more embodiments can also be applied to various products, such as a rollable TV, a stretchable display, etc.

[0146] The light emitting device according to one or more embodiments can emit a plurality of different wavelengths of light.

[0147] In the light emitting device according to one or more embodiments, a plurality of light emitting elements are vertically stacked, and thus a relatively wide active layer can be secured to increase light emitting efficiency.

[0148] In the light emitting device according to one or more embodiments, holes for forming electrodes are uniformly distributed on the upper and lower surfaces of the light emitting device, thereby uniformly securing an active area of the active layer.

[0149] When the light emitting device according to one or more embodiments is used, a display apparatus can be manufactured without using advanced transfer technology.

[0150] When the light emitting device according to one or more embodiments is used, a display apparatus having improved light emitting efficiency can be manufactured.

[0151] It should be understood that the embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. While embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details can be made therein without departing from the spirit and scope as defined by the following claims and their equivalents.

[0152] This application claims priority to Korean Patent Application No. 10-2024-0136824, filed on October 8, 2024, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

Claims

1. A display apparatus comprising: a display layer including a plurality of light emitting devices; and a driving layer configured to drive the plurality of light emitting devices, wherein at least one light emitting device of the plurality of light emitting devices includes: a first insulating layer; a light emitting structure including a first light emitting element, a second light emitting element, and a third light emitting element in order and monolithically on the first insulating layer, each of the first light emitting element, the second light emitting element, and the third light emitting element including a p-type semiconductor layer, an active layer, and an n-type semiconductor layer and configured to emit light of a different wavelength, a first electrode pattern including a first electrode, a second electrode, and a third electrode electrically connected to the p-type semiconductor layer of the first light emitting element, the p-type semiconductor layer of the second light emitting element, and the p-type semiconductor layer of the third light emitting element, respectively, the first electrode, the second electrode, and the third electrode being exposed on a surface of the first insulating layer; and a second electrode pattern including a fourth electrode, a fifth electrode, and a sixth electrode electrically connected to the n-type semiconductor layer of the first light emitting element, the n-type semiconductor layer of the second light emitting element, and the n-type semiconductor layer of the third light emitting element, respectively, the fourth electrode, the fifth electrode, and the sixth electrode being exposed on a surface of the third light emitting element. 2.The display apparatus of claim 1, wherein the first electrode penetrates the first insulating layer and contacts the p-type semiconductor layer of the first light emitting element, wherein the fourth electrode penetrates the third light emitting element and the second light emitting element and contacts the n-type semiconductor layer of the first light emitting element, and wherein the first light emitting element is configured to emit first light based on an electrical signal applied to the first electrode and an electrical signal applied to the fourth electrode. 3.The display apparatus of claim 1, wherein the second electrode penetrates the first insulating layer and the first light emitting element and contacts the p-type semiconductor layer of the second light emitting element, the fifth electrode penetrates the third light emitting element and contacts the n-type semiconductor layer of the second light emitting element, and wherein the second light emitting element is configured to emit second light based on an electrical signal applied to the second electrode and an electrical signal applied to the fifth electrode. 4.The display apparatus of claim 1, wherein the third electrode penetrates the first insulating layer, the first light emitting element, and the second light emitting element and contacts the p-type semiconductor layer of the third light emitting element, wherein the sixth electrode contacts a surface of the n-type semiconductor layer of the third light emitting element, and wherein the third light emitting element is configured to emit third light based on an electrical signal applied to the third electrode and an electrical signal applied to the sixth electrode. 5.The display apparatus of claim 1, wherein the first electrode, the second electrode, and the third electrode are not electrically connected to each other. 6.The display apparatus of claim 1, wherein the fourth electrode, the fifth electrode, and the sixth electrode are electrically connected to each other. ​ 7. The display device according to claim 6, wherein the sixth electrode is on a surface of the third light-emitting element and contacts the fourth electrode and the fifth electrode.

8. The display device according to claim 1, wherein the light-emitting structure does not include a bonding material.

9. The display device according to claim 1, wherein In each of the first light-emitting element, the second light-emitting element, and the third light-emitting element, the p-type semiconductor layer, the active layer, and the n-type semiconductor layer are sequentially on the driving layer.

10. The display device according to claim 1, wherein a wavelength of light emitted by the first light-emitting element is longer than a wavelength of light emitted by the second light-emitting element, and the wavelength of light emitted by the second light-emitting element is longer than a wavelength of light emitted by the third light-emitting element.

11. The display device according to claim 1, further comprising an optical layer on the display layer, the optical layer configured to control a travel path of light emitted from the display layer.

12. The display device according to claim 11, wherein the optical layer includes a plurality of microlenses corresponding one-to-one to the plurality of light-emitting devices.

13. The display device according to claim 1, wherein the display layer includes: first and second light-emitting devices of the plurality of light-emitting devices adjacent to each other; and a pixel separation portion configured to separate the first and second light-emitting devices.

14. The display device according to claim 13, wherein the pixel separation portion is configured to spatially separate a p-type semiconductor layer of a first light-emitting element, a second light-emitting element, and a third light-emitting element included in the first light-emitting device and an active layer of the third light-emitting element from a p-type semiconductor layer of a first light-emitting element, a second light-emitting element, and a third light-emitting element included in the second light-emitting device and an active layer of the third light-emitting element.

15. The display device according to claim 13, wherein an n-type semiconductor layer of the third light-emitting element included in the first light-emitting device and an n-type semiconductor layer of the third light-emitting element included in the second light-emitting device are connected to each other.

16. The display device according to claim 13, wherein a sixth electrode included in the first light-emitting device and a sixth electrode included in the second light-emitting device are connected to each other and on the same plane.

17. The display device according to claim 13, further comprising: a reflective layer on at least a part of a side surface of the pixel separation portion and a surface of the first light-emitting element.

18. The display device according to claim 13, further comprising: a second insulating layer filling at least a part of an inner space of the pixel separation portion and a space between the display layer and the driving layer, wherein the second insulating layer includes at least one of a black matrix material, a resin, and a polymer.

19. A method of manufacturing a display device, the method comprising: ​ forming a light emitting structure including a first light emitting element, a second light emitting element, and a third light emitting element on a sacrificial layer, each of the first light emitting element, the second light emitting element, and the third light emitting element including a p-type semiconductor layer, an active layer, and an n-type semiconductor layer and configured to emit light of different wavelengths; forming a first insulating layer on a surface of the first light emitting element of the light emitting structure; forming a first electrode pattern including a first electrode, a second electrode, and a third electrode electrically connected to the p-type semiconductor layer of the first light emitting element, the p-type semiconductor layer of the second light emitting element, and the p-type semiconductor layer of the third light emitting element, respectively, and exposed on a surface of the first insulating layer; bonding the first electrode pattern on a driving layer configured to drive the light emitting structure; removing the sacrificial layer from the light emitting structure; and forming a second electrode pattern including a fourth electrode, a fifth electrode, and a sixth electrode electrically connected to the n-type semiconductor layer of the first light emitting element, the n-type semiconductor layer of the second light emitting element, and the n-type semiconductor layer of the third light emitting element, respectively, and exposed on a surface of the third light emitting element. 20.The method of claim 19, further comprising: forming a pixel separation part configured to separate the light emitting structure into a plurality of pixels. ​

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