light-emitting diode

Abstract

To provide a light-emitting diode having a plurality of light-emitting units.SOLUTION: A light-emitting diode 1a includes a substrate 10, a buffer layer 20, and at least two light-emitting units. The buffer layer is arranged on the substrate. The at least two light-emitting units are arranged on the buffer layer in a sequentially laminated manner. Each light-emitting unit has a semiconductor light emitting structure 31 and a two-dimensional material layer 32. The two-dimensional material layer is arranged on the semiconductor light emitting structure. The number of the at least two light-emitting units is 2, that is, constituted of a first light-emitting unit 30a and a second light-emitting unit 30b. Each light-emitting unit emits light with a specific wavelength by the semiconductor light emitting structure. A specific wavelength of the light-emitting unit closer to the substrate out of the at least two light-emitting units is a specific wavelength of the light-emitting unit farther from the substrate or more.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a light emitting diode, and more particularly to a light emitting diode having a plurality of light emitting units. [Background technology]

[0002] In recent years, light-emitting diodes (LEDs) have been widely used for lighting in a variety of fields and products. Currently, typical LEDs convert electrical energy into light energy through the electroluminescence effect by passing electricity across the junction interface between two different semiconductor materials. As a result, LEDs not only emit light with high brightness, but also have energy-saving and power-saving effects.

[0003] Although the wavelength of light can be changed by using different semiconductor materials, most conventional light-emitting diodes can only emit light of a single wavelength by using a single light-emitting structure, which limits their applications. Some light-emitting diodes combine two light-emitting structures, but combining the two structures requires the use of materials with similar lattice constants (or emission wavelengths). Similarly, such conventional light-emitting diodes have limitations in terms of structural design and applications.

[0004] Therefore, how to design a light-emitting diode that can improve the above problems is a topic worth investigating. Summary of the Invention

[0005] SUMMARY OF THE INVENTION An object of the present invention is to provide a light emitting diode having a plurality of light emitting units.

[0006] Another object of the present invention is to provide a light emitting diode that can emit light at multiple wavelengths.

[0007] To achieve the above object, the light-emitting diode according to the present invention includes a substrate, a buffer layer, and at least two light-emitting units. The buffer layer is disposed on the substrate. The at least two light-emitting units are sequentially stacked on the buffer layer. Each light-emitting unit has a semiconductor light-emitting structure and a two-dimensional material layer. The two-dimensional material layer is disposed on the semiconductor light-emitting structure. Each light-emitting unit emits light of a specific wavelength through the semiconductor light-emitting structure. Of the at least two light-emitting units, the specific wavelength of the light-emitting unit closer to the substrate is equal to or longer than the specific wavelength of the light-emitting unit farther from the substrate.

[0008] In an embodiment of the present invention, the at least two light-emitting units include a first light-emitting unit disposed on a buffer layer and a second light-emitting unit disposed on the two-dimensional material layer of the first light-emitting unit, and the semiconductor light-emitting structure of the first light-emitting unit is different from the semiconductor light-emitting structure of the second light-emitting unit.

[0009] In an embodiment of the present invention, the semiconductor light-emitting structure includes a first-type semiconductor epitaxial layer, a light-emitting layer, and a second-type semiconductor epitaxial layer, and the stacking order of the first-type semiconductor epitaxial layer, the light-emitting layer, and the second-type semiconductor epitaxial layer of the first light-emitting unit is reverse to the stacking order of the first-type semiconductor epitaxial layer, the light-emitting layer, and the second-type semiconductor epitaxial layer of the second light-emitting unit.

[0010] In an embodiment of the present invention, the horizontal cross-sectional area of ​​the first light-emitting unit is smaller than that of the buffer layer, and the horizontal cross-sectional area of ​​the second light-emitting unit is smaller than that of the first light-emitting unit.

[0011] In an embodiment of the present invention, the buffer layer is made of a two-dimensional material.

[0012] In an embodiment of the present invention, the light-emitting diode further comprises a base electrode disposed on the buffer layer, the base electrode being spaced apart from the at least two light-emitting units in the horizontal direction.

[0013] In an embodiment of the present invention, each light-emitting unit further includes an additional electrode disposed on the two-dimensional material layer, and the additional electrode of each light-emitting unit is horizontally spaced apart from other adjacent light-emitting units.

[0014] In an embodiment of the present invention, the material of the two-dimensional material layer is selected from the group consisting of molybdenum disulfide, tungsten disulfide, molybdenum diselenide, and tungsten diselenide.

[0015] In embodiments of the present invention, the substrate is made of gallium nitride, sapphire, silicon, or gallium arsenide.

[0016] According to the design of the present invention, the light-emitting diode of the present invention is designed to stack multiple light-emitting units on a single structural member. By controlling the on / off of each light-emitting unit, one or more light-emitting units can be driven to emit light of different wavelengths. In addition, the use of two-dimensional materials for the conductive layers of different light-emitting units can effectively increase the electronic conductivity and reduce the resistance and driving voltage of the light-emitting units. It is also possible to combine light-emitting units with different lattice constants that differ greatly. [Brief explanation of the drawings]

[0017] [Figure 1] Schematic diagram showing a light-emitting diode according to the present invention. [Figure 2] 1 is a schematic diagram showing a light-emitting diode according to a first embodiment of the present invention; [Figure 3] FIG. 1 is a schematic diagram showing a light-emitting diode according to a second embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0018] Each embodiment and example is merely illustrative and not limiting, and after reading this specification, a person skilled in the art can make other embodiments and examples without departing from the scope of the present invention. The features and advantages of the embodiments of the present invention will become more apparent from the following detailed description and claims.

[0019] The terms "one" or "an" are used herein to describe elements and components described herein for convenience and to give a general sense of the scope of the invention. Accordingly, unless otherwise indicated, such descriptions are understood to include one or at least one, and the singular also includes the plural.

[0020] As used herein, the ordinal terms "first" and "second" are primarily used to distinguish or refer to identical or similar components or structures, and do not necessarily imply a spatial or temporal ordering of these components or structures. It should be noted that in certain situations or configurations, the ordinal terms may be used interchangeably without affecting the practice of the present invention.

[0021] As used herein, the terms "comprise," "have," or other similar terms are intended to be non-exclusive inclusions. For example, a component or structure comprising multiple elements is not limited to only the elements listed herein, but may include other elements not expressly listed but inherent to the component or structure.

[0022] FIG. 1 is a schematic diagram showing a light-emitting diode according to the present invention. As shown in FIG. 1, the light-emitting diode 1 according to the present invention includes a substrate 10, a buffer layer 20, and at least two light-emitting units 30. The substrate 10 is a base member of the light-emitting diode 1 according to the present invention and is used to mount the buffer layer 20, the at least two light-emitting units 30, and other components. In the present invention, the substrate 10 is made of gallium nitride (GaN), sapphire, silicon (Si), or gallium arsenide (GaAs). However, the substrate 10 may also be made of other common substrate materials.

[0023] The buffer layer 20 is disposed on the substrate 10. In the present invention, the buffer layer 20 is made of a two-dimensional material. The two-dimensional material is selected from the group consisting of molybdenum disulfide (MoS2), tungsten disulfide (WS2), molybdenum diselenide (MoSe2), and tungsten diselenide (WSe2). The buffer layer 20 has a single atomic layer or a multi-layer structure formed by stacking multiple atomic layers, but the present invention is not limited thereto. The buffer layer 20 may also be made of other two-dimensional materials with similar properties. The buffer layer 20 can relieve stress on the surface of the substrate 10 and improve the bonding between the substrate 10 and the adjacent light-emitting unit 30. Furthermore, two-dimensional materials have high electronic conductivity, thereby providing good electrical conductivity.

[0024] At least two light-emitting units 30 are sequentially stacked on the buffer layer 20. That is, except for the light-emitting unit 30 adjacent to the buffer layer 20, the other light-emitting units 30 are disposed on top of other light-emitting units 30, thereby forming a stack of multiple light-emitting units 30. In the present invention, the number of light-emitting units 30 is at least two, and may be increased to two or more depending on the design. Each light-emitting unit 30 includes a semiconductor light-emitting structure 31 and a two-dimensional material layer 32. The semiconductor light-emitting structure 31 is a base member of the light-emitting unit 30, which emits light of a specific wavelength after conduction. That is, the semiconductor light-emitting structure 31 of each light-emitting unit 30 corresponds to a specific wavelength. The specific wavelength varies depending on the material of the semiconductor light-emitting structure 31.

[0025] The two-dimensional material layer 32 of each light-emitting unit 30 is disposed on the semiconductor light-emitting structure 31. The two-dimensional material layer 32 is a single atomic layer or a stacked structure of multiple atomic layers. The two-dimensional material layer 32 primarily functions as a conductive layer. Two-dimensional materials have high electronic conductivity, providing good electrical conductivity and reducing the resistance and driving voltage of adjacent light-emitting units. The two-dimensional material layer 32 also solves the problem of lattice constant mismatch that may occur between different materials, allowing different light-emitting units with large differences in lattice constant (or large differences in emission wavelength) to be smoothly combined. In the present invention, the material of the two-dimensional material layer 32 is also selected from the group consisting of molybdenum disulfide (MoS2), tungsten disulfide (WS2), molybdenum diselenide (MoSe2), and tungsten diselenide (WSe2). For example, the same two-dimensional material as the buffer layer 20 can be used, but the present invention is not limited thereto.

[0026] By design, the specific wavelength of the light-emitting unit 30 closest to the substrate 10 among at least two light-emitting units 30 is equal to or greater than the specific wavelength of the light-emitting unit 30 farthest from the substrate 10. That is, among the stacked light-emitting units 30, the specific wavelength of the lower light-emitting unit 30 is equal to or greater than the specific wavelength of the upper light-emitting unit 30. When a light-emitting unit 30 is selected and its two-dimensional material layer 32 is electrically connected to the two-dimensional material layer 32 of the other light-emitting unit 30 adjacent thereto below, or to the buffer layer 20 adjacent thereto below, the selected light-emitting unit 30 emits light of a specific wavelength through its semiconductor light-emitting structure 31. Therefore, the light-emitting diode 1 of the present invention can control the on / off of each light-emitting unit 30 and drive a desired single or multiple light-emitting units 30 to achieve different light-emitting effects.

[0027] The following describes the light-emitting diode according to the present invention based on its actual structure. FIG. 2 is a schematic diagram showing a light-emitting diode according to a first embodiment of the present invention. As shown in FIG. 2, in this embodiment, the number of at least two light-emitting units in the light-emitting diode 1a according to the present invention is two, namely, a first light-emitting unit 30a and a second light-emitting unit 30b. The first light-emitting unit 30a is disposed on the buffer layer 20. The second light-emitting unit 30b is disposed on the first light-emitting unit 30a. In terms of structural design, the horizontal cross-sectional area of ​​the first light-emitting unit 30a is smaller than the horizontal cross-sectional area of ​​the substrate 10 and the buffer layer 20. Therefore, the entire first light-emitting unit 30a is disposed on the buffer layer 20. The horizontal cross-sectional area of ​​the second light-emitting unit 30b is smaller than the horizontal cross-sectional area of ​​the first light-emitting unit 30a. Therefore, the entire second light-emitting unit 30b is disposed on the first light-emitting unit 30a.

[0028] In this embodiment, the semiconductor light emitting structure 31 of the first light emitting unit 30a includes a first-type semiconductor epitaxial layer 311, a light emitting layer 312, and a second-type semiconductor epitaxial layer 313. The semiconductor light emitting structure 31 is formed in the stacking order of the first-type semiconductor epitaxial layer 311, the light emitting layer 312, and the second-type semiconductor epitaxial layer 313. The semiconductor light emitting structure 31 of the second light emitting unit 30b also includes a first-type semiconductor epitaxial layer 311, the light emitting layer 312, and the second-type semiconductor epitaxial layer 313. However, the semiconductor light emitting structure 31 of the second light emitting unit 30b is formed in the stacking order of the second-type semiconductor epitaxial layer 313, the light emitting layer 312, and the first-type semiconductor epitaxial layer 311. That is, the semiconductor light emitting structure 31 of the first light emitting unit 30a and the semiconductor light emitting structure 31 of the second light emitting unit 30b have the epitaxial layer stacking order reversed. For example, if the first-type semiconductor epitaxial layer 311 is an N-type semiconductor epitaxial layer, the light emitting layer 312 is a multiple quantum well (MQW) layer, and the second-type semiconductor epitaxial layer 313 is a P-type semiconductor epitaxial layer, the semiconductor light emitting structure 31 of the first light emitting unit 30a has an N-MQW-P epitaxial stacking structure, and the semiconductor light emitting structure 31 of the second light emitting unit 30b has a P-MQW-N epitaxial stacking structure. However, the present invention is not limited to this. The epitaxial layer stacking order of the semiconductor light emitting structure 31 of the first light emitting unit 30a and the semiconductor light emitting structure 31 of the second light emitting unit 30b may be reversed.

[0029] In this embodiment, the light-emitting diode 1a according to the present invention further includes a base electrode 40. The base electrode 40 is electrically connected to the buffer layer 20. The base electrode 40 is connected to an external power source via a wire to supply power to the buffer layer 20. In terms of structural design, the base electrode 40 is disposed on the buffer layer 20. The base electrode 40 is horizontally spaced apart from the first light-emitting unit 30a. The base electrode 40 is made of a metal material, but the present invention is not limited thereto.

[0030] The first light-emitting unit 30a and the second light-emitting unit 30b of the light-emitting diode 1a according to the present invention each have an additional electrode 33. The additional electrode 33 of each light-emitting unit is electrically connected to the two-dimensional material layer 32 of the light-emitting unit. The additional electrode 33 is connected to an external power source via a wire to supply power to the two-dimensional material layer 32. In terms of structural design, the additional electrode 33 of each light-emitting unit is disposed on the two-dimensional material layer 32 of the light-emitting unit. The additional electrode 33 of the first light-emitting unit 30a is horizontally spaced apart from the adjacent second light-emitting unit 30b. Although the additional electrode 33 is made of a metal material, the present invention is not limited thereto.

[0031] In this embodiment, the specific wavelength of the first light-emitting unit 30a is λ1, and the specific wavelength of the second light-emitting unit 30b is λ2. In terms of circuit design, the base electrode 40 of the light-emitting diode 1a of the present invention is connected to the switch S1 via a lead wire, the additional electrode 33 of the first light-emitting unit 30a is connected to the switch S2 via a lead wire, and the additional electrode 33 of the second light-emitting unit 30b is connected to the switch S3 via a lead wire. When only the switches S1 and S2 are turned on, the light-emitting diode 1a of the present invention emits light with the specific wavelength λ1 through the first light-emitting unit 30a. When only the switches S2 and S3 are turned on, the light-emitting diode 1a of the present invention emits light with the specific wavelength λ2 through the second light-emitting unit 30b. When the switches S1, S2, and S3 are turned on, the light-emitting diode 1a of the present invention emits light with the specific wavelength λ1 + λ2 through the first light-emitting unit 30a and the second light-emitting unit 30b. Table 1 shows the light-emitting effects corresponding to the states of the switches. Therefore, the light-emitting diode 1a of the present invention can achieve the effect of emitting light of different wavelengths by driving any one light-emitting unit to emit light alone or by driving multiple light-emitting units to emit light simultaneously. [Table 1]

[0032] FIG. 3 is a schematic diagram showing a light-emitting diode according to a second embodiment of the present invention. As shown in FIG. 3, in this embodiment, the number of at least two light-emitting units in the light-emitting diode 1b according to the present invention is n, that is, the light-emitting diode 1b is composed of a first light-emitting unit 30a, a second light-emitting unit 30b, ..., an n-th light-emitting unit 30n, where n≧3. The first light-emitting unit 30a is disposed on the buffer layer 20. The second light-emitting unit 30b is disposed on the first light-emitting unit 30a. The n-th light-emitting unit 30n is disposed on the (n-1)th light-emitting unit (when n=3, the (n-1)th light-emitting unit is the second light-emitting unit 30b). In terms of structural design, the horizontal cross-sectional area of ​​the first light-emitting unit 30a is smaller than the horizontal cross-sectional areas of the substrate 10 and the buffer layer 20. Therefore, the entire first light-emitting unit 30a is disposed on the buffer layer 20. The horizontal cross-sectional area of ​​the second light-emitting unit 30b is smaller than the horizontal cross-sectional area of ​​the first light-emitting unit 30a. As a result, the second light-emitting unit 30b is entirely disposed above the first light-emitting unit 30a. The horizontal cross-sectional area of ​​the nth light-emitting unit 30n is smaller than the horizontal cross-sectional area of ​​the (n-1)th light-emitting unit. As a result, the nth light-emitting unit 30n is entirely disposed above the (n-1)th light-emitting unit.

[0033] When the number of light-emitting units is three or more, the semiconductor light-emitting structure of any one of the light-emitting units is different from the semiconductor light-emitting structure of the adjacent light-emitting unit. In this embodiment, the semiconductor light-emitting structure 31 of the first light-emitting unit 30a is formed in the stacking order of the first-type semiconductor epitaxial layer 311, the light-emitting layer 312, and the second-type semiconductor epitaxial layer 313. The semiconductor light-emitting structure 31 of the second light-emitting unit 30b is formed in the stacking order of the second-type semiconductor epitaxial layer 313, the light-emitting layer 312, and the first-type semiconductor epitaxial layer 311. The semiconductor light-emitting structures of the odd-numbered light-emitting units after the second light-emitting unit 30b (e.g., the third light-emitting unit, the fifth light-emitting unit, ...) are the same as the semiconductor light-emitting structure 31 of the first light-emitting unit 30a, and are formed in the stacking order of the first-type semiconductor epitaxial layer 311, the light-emitting layer 312, and the second-type semiconductor epitaxial layer 313. The semiconductor light-emitting structures of the even-numbered light-emitting units (e.g., the fourth light-emitting unit, the sixth light-emitting unit, ...) are the same as the semiconductor light-emitting structure 31 of the second light-emitting unit 30b, and are formed in the same stacking order as the second-type semiconductor epitaxial layer 313, the light-emitting layer 312, and the first-type semiconductor epitaxial layer 311. That is, when the number of light-emitting units is three or more, the stacking order of the first-type semiconductor epitaxial layer, the light-emitting layer, and the second-type semiconductor epitaxial layer of any one of these light-emitting units is reverse to the stacking order of the first-type semiconductor epitaxial layer, the light-emitting layer, and the second-type semiconductor epitaxial layer of the other adjacent light-emitting units. For example, if the semiconductor light-emitting structures of the odd-numbered light-emitting units all have an N-MQW-P epitaxial stacking structure, the semiconductor light-emitting structures of the even-numbered light-emitting units all have a P-MQW-N epitaxial stacking structure, but the present invention is not limited to this.

[0034] In this embodiment, the light-emitting diode 1b according to the present invention also further includes a base electrode 40. The position of the base electrode 40 is the same as in the first embodiment, and therefore its description will be omitted. The first light-emitting unit 30a, the second light-emitting unit 30b, ..., the n-th light-emitting unit 30n of the light-emitting diode 1b according to the present invention each include an additional electrode 33. The additional electrode 33 of each light-emitting unit is electrically connected to the two-dimensional material layer 32 of the light-emitting unit. The additional electrode 33 is connected to an external power source via a wire to supply power to the two-dimensional material layer 32. In terms of structural design, the additional electrode 33 of each light-emitting unit is disposed on the two-dimensional material layer 32 of the light-emitting unit. The additional electrode 33 of the first light-emitting unit 30a is spaced apart from the second light-emitting unit 30b, ..., and the additional electrode of the (n-1)th light-emitting unit is spaced apart from the n-th light-emitting unit 30n.

[0035] In this embodiment, the specific wavelength of the first light-emitting unit 30a is λ1, the specific wavelength of the second light-emitting unit 30b is λ2, ..., the specific wavelength of the n-th light-emitting unit 30n is λn, where λ1 ≥ λ2 ≥ ... ≥ λn holds. In terms of circuit design, the light-emitting diode 1b of the present invention has the base electrode 40 connected to the switch S1 by a lead wire, the additional electrode 33 of the first light-emitting unit 30a connected to the switch S2 by a lead wire, the additional electrode 33 of the second light-emitting unit 30b connected to the switch S3 by a lead wire, ..., the additional electrode 33 of the n-th light-emitting unit 30n connected to the switch Sn+1 by a lead wire. When only the switches S1 and S2 are turned on, the light-emitting diode 1b of the present invention emits light of the specific wavelength λ1 through the first light-emitting unit 30a. When only the switches S2 and S3 are turned on, the light-emitting diode 1b of the present invention emits light of the specific wavelength λ2 through the second light-emitting unit 30b. When only switch Sn (when n=3, switch Sn is switch S3) and switch Sn+1 are turned on, the light emitting diode 1b of the present invention emits light of a specific wavelength λn through the n-th light emitting unit 30n. When switch S1, switch S2, and switch S3 are turned on, the light emitting diode 1b of the present invention emits light of a specific wavelength λ1+λ2 through the first light emitting unit 30a and the second light emitting unit 30b. When switch S1, switch S2, switch Sn, and switch Sn+1 are turned on, the light emitting diode 1b of the present invention emits light of a specific wavelength λ1+λn through the first light emitting unit 30a and the n-th light emitting unit 30n. When all switches S1 to Sn+1 are turned on, the light emitting diode 1b of the present invention emits light of a specific wavelength λ1+λ2+...+λn through the first light emitting unit 30a to the n-th light emitting unit 30n. Table 2 shows the light emitting effect corresponding to each switch state. Therefore, the light-emitting diode 1b of the present invention can also achieve the effect of emitting light of different wavelengths by driving any one light-emitting unit to emit light alone or by driving multiple light-emitting units to emit light simultaneously. [Table 2]

[0036] The above-described embodiments are merely illustrative and are not intended to limit the embodiments or applications of the present application. Furthermore, while the above-described embodiments provide at least one illustrative example, it should be understood that numerous variations of the present invention are possible. Furthermore, the examples described herein are not intended to limit the scope, application, or configuration of the claims in any way. Rather, the above-described embodiments provide a guide for those skilled in the art to implement one or more of the embodiments. Furthermore, changes may be made in the function and arrangement of elements without departing from the scope of the claims, which include all known and foreseeable equivalents at the time of filing this patent application. [Explanation of symbols]

[0037] 1, 1a, 1b light-emitting diodes 10 Substrate 20 Buffer Layer 30 Lighting Unit 30a First light-emitting unit 30b Second light-emitting unit 30n nth light-emitting unit 31 Semiconductor light-emitting structure 311 Type 1 semiconductor epitaxial layer 312 Light-emitting layer 313 Type 2 semiconductor epitaxial layer 32 Two-dimensional material layer 33 Additional electrodes 40 Base Electrode S1, S2, S3, Sn+1 switches

Claims

1. A light emitting diode, A substrate; a buffer layer disposed on the substrate; and at least two light-emitting units, which are sequentially stacked on the buffer layer and have a semiconductor light-emitting structure and a two-dimensional material layer disposed on the semiconductor light-emitting structure, and which emit light of a specific wavelength by the semiconductor light-emitting structure; the specific wavelength of the light-emitting unit closer to the substrate among the at least two light-emitting units is equal to or longer than the specific wavelength of the light-emitting unit farther from the substrate; Each of the light-emitting units further comprises an additional electrode disposed on the two-dimensional material layer; The additional electrode of each of the light-emitting units is horizontally spaced apart from other adjacent light-emitting units.

2. 2. The light-emitting diode of claim 1, wherein the at least two light-emitting units include a first light-emitting unit disposed on the buffer layer and a second light-emitting unit disposed on the two-dimensional material layer of the first light-emitting unit, and the semiconductor light-emitting structure of the first light-emitting unit is different from the semiconductor light-emitting structure of the second light-emitting unit.

3. the semiconductor light emitting structure includes a first-type semiconductor epitaxial layer, a light emitting layer, and a second-type semiconductor epitaxial layer; 3. The light-emitting diode according to claim 2, wherein the stacking order of the first-type semiconductor epitaxial layer, the light-emitting layer, and the second-type semiconductor epitaxial layer of the first light-emitting unit is reverse to the stacking order of the first-type semiconductor epitaxial layer, the light-emitting layer, and the second-type semiconductor epitaxial layer of the second light-emitting unit.

4. 3. The light-emitting diode of claim 2, wherein the horizontal cross-sectional area of ​​the first light-emitting unit is smaller than the horizontal cross-sectional area of ​​the buffer layer, and the horizontal cross-sectional area of ​​the second light-emitting unit is smaller than the horizontal cross-sectional area of ​​the first light-emitting unit.

5. 2. The light-emitting diode according to claim 1, wherein when the number of the light-emitting units is three or more, the semiconductor light-emitting structure of any one of the light-emitting units is different from the semiconductor light-emitting structure of another adjacent light-emitting unit.

6. the semiconductor light emitting structure includes a first-type semiconductor epitaxial layer, a light emitting layer, and a second-type semiconductor epitaxial layer; 6. The light-emitting diode according to claim 5, wherein the stacking order of the first-type semiconductor epitaxial layer, the light-emitting layer, and the second-type semiconductor epitaxial layer of any one of the light-emitting units is opposite to the stacking order of the first-type semiconductor epitaxial layer, the light-emitting layer, and the second-type semiconductor epitaxial layer of another adjacent light-emitting unit.

7. 2. The light emitting diode of claim 1, wherein the buffer layer is made of a two-dimensional material.

8. a base electrode disposed on the buffer layer; 2. The light-emitting diode of claim 1, wherein the base electrode is horizontally spaced apart from the at least two light-emitting units.

9. 2. The light-emitting diode of claim 1, wherein the material of the two-dimensional material layer is selected from the group consisting of molybdenum disulfide, tungsten disulfide, molybdenum diselenide, and tungsten diselenide.

10. 10. The light emitting diode of claim 1, wherein the substrate is made of gallium nitride, sapphire, silicon, or gallium arsenide.

Images