Light emitting diode and light emitting device

Abstract

The invention discloses a light-emitting diode, and the light-emitting diode comprises a semiconductor epitaxial lamination layer which is provided with a first surface and a second surface which are opposite to each other, and comprises a first type semiconductor layer, an active layer and a second type semiconductor layer which are sequentially stacked in the direction from the first surface to the second surface; a first spacing layer is arranged between the first type semiconductor layer and the active layer; a second spacing layer is arranged between the second type semiconductor layer and the active layer; the structure is characterized in that the second spacing layer is of a multi-layer structure formed by stacking sub-layers formed by two or more than two materials. According to the invention, the blocking effect of the second spacing layer on defects such as diffusion and dislocation of doped atoms can be enhanced, so that the thickness of the second spacing layer is reduced to the greatest extent, the radiation recombination proportion of carriers in the active layer is improved, and the internal quantum efficiency and ESD performance of the light-emitting diode are improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing, and in particular to a light emitting diode and a light emitting device. Background Art

[0002] Light Emitting Diode (LED) is a device that uses P-type semiconductors to provide holes and N-type semiconductors to provide electrons. In the active layer, holes in the valence band and electrons in the conduction band undergo radiation recombination to convert electrical energy into light energy. Light Emitting Diode has the advantages of high luminous intensity, high efficiency, small size, and long service life. It is considered to be one of the most promising light sources. In recent years, LEDs have been widely used in daily life.

[0003] In existing light-emitting diodes, an unintentionally doped P-type spacer layer is grown between the active layer and the P-type cover layer that provides P-type carriers (holes), and an unintentionally doped N-type spacer layer is grown between the active layer and the N-type cover layer that provides N-type carriers (electrons). On the one hand, they are used to block the diffusion of P-type doping atoms and N-type doping atoms into the active layer, thereby solving the problem of reduced brightness caused by non-radiative recombination of carriers, and at the same time solving the problem of reduced quality of active layer crystals caused by diffusion of doping atoms into the active layer, thereby reducing reliability. On the other hand, the P-type spacer layer and the N-type spacer layer with higher potential barriers can effectively confine most of the carriers in the active layer, thereby improving the internal quantum efficiency of the LED.

[0004] In order to effectively block P-type and N-type doping atoms such as Mg and Si from diffusing into the active layer and ensure the radiation recombination efficiency and reliability of the light-emitting diode, the thickness of the traditional P-type and N-type spacer layers is set to be thicker, and the radiation recombination of carriers in the active layer accounts for a low proportion. Some carriers undergo non-radiative recombination in the spacer layer, causing the light-emitting diode to self-heat, making it difficult to further improve the efficiency of the light-emitting diode. At the same time, the thicker spacer layer setting will also lead to a higher operating voltage of the light-emitting diode and is not conducive to improving the ESD performance. Summary of the invention

[0005] In order to solve at least one problem existing in the prior art, the present invention proposes a light-emitting diode and a light-emitting device, wherein the light-emitting diode comprises: a semiconductor epitaxial stack having a first surface and a second surface opposite to each other, and comprising a first type semiconductor layer, an active layer, and a second type semiconductor layer stacked in sequence from the first surface to the second surface; a first spacer layer is included between the first type semiconductor layer and the active layer; a second spacer layer is included between the second type semiconductor layer and the active layer; and the second spacer layer is characterized in that the second spacer layer is a multilayer structure formed by stacking sublayers formed by two or more materials.

[0006] The present invention further provides a light emitting device, characterized by comprising the aforementioned light emitting diode.

[0007] The second spacer layer of the present invention is arranged as a multilayer structure formed by stacking two or more sub-layers of different materials, which can enhance the blocking effect of the second spacer layer on the diffusion of doping atoms and defects such as dislocations, thereby minimizing the thickness of the second spacer layer, increasing the proportion of carriers undergoing radiation recombination in the active layer, and achieving improvements in the internal quantum efficiency and ESD performance of the light-emitting diode.

[0008] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In addition, the accompanying drawings are description outlines and are not drawn to scale.

[0010] Figure 1 It is a schematic diagram of the epitaxial structure mentioned in Example 1 of the present invention.

[0011] Figure 2 It is a schematic diagram of the structure of the light emitting diode mentioned in Example 1 of the present invention.

[0012] Figure 3~Figure 4 It is a schematic diagram of the structure of the light emitting diode manufacturing process mentioned in Example 2 of the present invention.

[0013] Figure 5 Schematic diagram of the structure of the light emitting diode mentioned in Example 3 of the present invention.

[0014] Figure 6 It is a schematic diagram of the structure of the light emitting diode mentioned in Example 4 of the present invention.

[0015] Figure 7 Schematic diagram of the structure of the micro-luminescent element mentioned in Example 4 of the present invention.

[0016] Figure 8~Figure 14 It is a structural schematic diagram of the preparation process of the micro-luminescent element mentioned in Example 5 of the present invention.

[0017] Fig.15 This is a schematic diagram of the epitaxial structure mentioned in Example 6.

[0018] Fig.16a , Fig.16b and Fig.16c Schematic diagram of the structure of the light emitting diode mentioned in the sixth embodiment.

[0019] Fig.17 This is a schematic diagram of the epitaxial structure mentioned in Example 7.

[0020] Fig.18a , Fig.18b and Fig.18c Schematic diagram of the structure of the light emitting diode mentioned in the seventh embodiment.

[0021] Fig.19 It is a schematic structural diagram of the light-emitting device mentioned in Example 8 of the present invention.

[0022] Reference numerals: growth substrate: 100; buffer layer: 101; etching stop layer: 102; first ohmic contact layer: 103; first current spreading layer: 104; first cover layer: 105; first spacer layer: 106; third sublayer: 106a; fourth sublayer: 106b; active layer: 107; second spacer layer: 108; first sublayer: 108a; second sublayer: 108b; second cover layer: 109; second current spreading layer: 110; second ohmic contact layer: 111; substrate: 200; bonding layer: 2 01; reflective structure: 202; metal reflective layer: 202a; dielectric material layer: 202b; first electrode: 203; ohmic contact portion of the first electrode: 203a; ohmic contact portion of the second electrode: 204a; second electrode: 204; pad electrode of the first electrode: 203b; pad electrode of the second electrode: 204b; first table: S1; second table: S2; insulating protective layer: 207; horizontal portion of the insulating protective layer: 2071; sacrificial layer: 208; base frame: 250; bridge arm: 240. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example 1

[0024] The present embodiment provides a light-emitting diode, in which the second spacer layer is configured as a multilayer structure formed by stacking two or more sub-layers of different materials, which can enhance the blocking effect of the second spacer layer on the diffusion of doping atoms and defects such as dislocations, thereby minimizing the thickness of the second spacer layer, increasing the proportion of carriers undergoing radiation recombination in the active layer, and achieving improvements in the internal quantum efficiency and ESD performance of the light-emitting diode.

[0025] Figure 1 Schematic diagram of a light-emitting diode epitaxial structure of a preferred embodiment, the light-emitting diode epitaxial structure includes: a growth substrate 100; a semiconductor epitaxial stack, including a first current spreading layer 104, a first covering layer 105, a first spacer layer 106, an active layer 107, a second spacer layer 108, a second covering layer 109, a second current spreading layer 110 and a second ohmic contact layer 111 stacked in sequence on the growth substrate 100.

[0026] Specifically, refer to Figure 1 , the material of the growth substrate 100 includes but is not limited to GaAs, and other materials may also be used, such as GaP, InP, etc. In this embodiment, a GaAs growth substrate 100 is taken as an example. Optionally, a buffer layer 101, an etching stop layer 102 and a first ohmic contact layer 103 are sequentially arranged between the growth substrate 100 and the first current spreading layer 104; wherein, since the lattice quality of the buffer layer 101 is better than that of the growth substrate 100, growing the buffer layer 101 on the growth substrate 100 is conducive to eliminating the influence of the lattice defects of the growth substrate 100 on the semiconductor epitaxial stack; the etching stop layer 102 is used as a stop layer for chemical etching in the later step, and in some optional embodiments, the etching stop layer 102 is an n-type etching stop layer, and the material is n-GaInP. In order to facilitate the subsequent removal of the growth substrate 100, its thickness is controlled within 500nm, and more preferably within 200nm. In some optional embodiments, the first ohmic contact layer 103 is made of GaAs material, with a thickness ranging from 10 to 100 nm and a doping concentration ranging from 1 to 10E+18 / cm 3 , preferably 2E18 / cm 3 , to achieve better ohmic contact results.

[0027] The semiconductor epitaxial stack can be formed on the growth substrate 100 by physical vapor deposition (PVD), chemical vapor deposition (CVD), epitaxial growth (Epitaxy Growth Technology) and atomic beam deposition (ALD). The semiconductor epitaxial stack is a semiconductor material that can provide conventional radiation such as ultraviolet, blue, green, yellow, red, infrared light, etc., and can specifically be a material of 200-950nm, such as common nitrides, specifically gallium nitride-based semiconductor epitaxial stacks, gallium nitride-based epitaxial stacks are commonly doped with elements such as aluminum and indium, and mainly provide radiation in the 200-550nm band; or common aluminum gallium indium phosphide-based or aluminum gallium arsenic-based semiconductor epitaxial stacks, mainly providing radiation in the 550-950nm band.

[0028] The semiconductor epitaxial stack has a first surface and a second surface relative to each other, and includes a first type semiconductor layer, an active layer, and a second type semiconductor layer stacked in sequence from the first surface to the second surface. The first type semiconductor layer and the second type semiconductor layer can be provided with electrons or holes by n-type doping or p-type doping, respectively. The n-type semiconductor layer can be doped with n-type dopants such as Si, Ge, or Sn, and the p-type semiconductor layer can be doped with p-type dopants such as Mg, Zn, Ca, Sr, C, or Ba. When the first type semiconductor layer is an n-type semiconductor, the second type semiconductor layer is a p-type semiconductor layer; when the first type semiconductor layer is a p-type semiconductor layer, the second type semiconductor layer is an n-type semiconductor layer. The first type semiconductor layer, the active layer, and the second conductive semiconductor layer can be made of materials such as aluminum gallium indium nitride, gallium nitride, aluminum gallium nitride, aluminum indium phosphide, aluminum gallium indium phosphide, or gallium arsenide or aluminum gallium arsenic. In this embodiment, it is preferred that the first type semiconductor layer is an n-type semiconductor layer and the second type semiconductor layer is a p-type semiconductor layer.

[0029] The first type semiconductor layer and the second type semiconductor layer include a first cover layer 105 and a second cover layer 109, such as aluminum gallium indium phosphide or aluminum indium phosphide or aluminum gallium arsenic, which respectively provide electrons or holes for the active layer 107. More preferably, when the material of the active layer 107 is aluminum gallium indium phosphide, aluminum indium phosphide is used as the first cover layer 105 and the second cover layer 109 to provide electrons and holes. In order to improve the uniformity of current expansion, the first type semiconductor layer and the second type semiconductor layer also include a first current expansion layer 104 and a second current expansion layer 110. In order to block N-type doping atoms and P-type doping atoms from diffusing into the active layer, thereby solving the problem of reduced brightness caused by non-radiative recombination of carriers, and at the same time solving the problem of reduced crystal quality of the active layer caused by diffusion of doping atoms into the active layer, thereby reducing reliability, in this embodiment, there is a first spacer layer 106 between the first cover layer 105 and the active layer 107; and there is a second spacer layer 108 between the second cover layer 109 and the active layer 107.

[0030] The first current spreading layer 104 plays a role in current spreading, and its spreading ability is related to its thickness. In this embodiment, the preferred material is Al u1 Ga 1-u1 InP, where 0<u1≤1. The thickness of the first current spreading layer 104 is 2500-4000nm, and the n-type doping concentration is 2E17-4E18 / cm 3 , preferably 4E17~2E18 / cm 3 The common n-type doping is Si doping, and other elements equivalently replacing doping are not excluded. The first cover layer 105 provides electrons for the active layer 107, and the material is Alz1 Ga 1-z1 InP, where 0<z1≤1, the preferred material is AlInP, with a thickness of 200~1500nm; the common n-type doping is Si doping, and other elements equivalently replacing doping are not excluded.

[0031] The first spacer layer 106 is located between the first cover layer 105 and the active layer 107, and is preferably made of Al a1 Ga 1- a1 InP, the thickness of the first spacer layer 106 is preferably less than 300nm, and the Al component content a1 ranges from 0.2 to 1; in this embodiment, the first spacer layer 106 is preferably n-type doped, and the doping concentration is lower than 2E17 / cm 3 .

[0032] The active layer 107 provides a light radiation area for electron and hole recombination. Different materials can be selected according to different luminescent wavelengths. The active layer 107 can be a periodic structure of a single quantum well or multiple quantum wells. In this embodiment, the active layer 107 is a quantum well structure of multiple periods, and each quantum well structure includes a well layer and a barrier layer deposited in sequence, wherein the barrier layer has a larger band gap than the well layer. By adjusting the composition ratio of the semiconductor material in the active layer 107, it is expected to radiate light of the target wavelength. The active layer 107 is a material layer that provides electroluminescent radiation, such as aluminum gallium indium phosphide or aluminum gallium arsenic, and more preferably aluminum gallium indium phosphide, and aluminum gallium indium phosphide is a single quantum well or multiple quantum wells. In this embodiment, the semiconductor epitaxial stack is preferably composed of AlGaInP-based or AlGaAs-based materials, and the active layer radiates light with a wavelength of 550~950nm.

[0033] The number of periods of the quantum well structure in this embodiment is 2 to 100. The well layer is composed of Al m Ga 1-m InP material; the barrier layer is composed of Al n Ga 1-n The well layer is made of InP material, wherein 0≤m≤n≤1. The thickness of the well layer is 2-25 nm, preferably 3-10 nm; the thickness of the barrier layer is 2-25 nm, preferably 4-10 nm. The Al component content y of the barrier layer is in the range of 0.3-1.

[0034] In order to effectively block P-type dopant atoms such as Mg from diffusing into the active layer and ensure the radiation recombination efficiency and reliability of the light-emitting diode, the thickness of the traditional P-type second spacer layer is set to be thicker, and the radiation recombination of carriers in the active layer accounts for a low proportion. Some carriers undergo non-radiative recombination in the second spacer layer, causing the light-emitting diode to self-heat, making it difficult to further improve the efficiency of the light-emitting diode. At the same time, the thicker spacer layer setting will also lead to a higher operating voltage for the light-emitting diode and is not conducive to improving the ESD performance. In order to solve the above problems, the second spacer layer in this embodiment is a multilayer structure formed by stacking sublayers formed by two or more materials. The second spacer layer is an unintentionally doped layer, and its main purpose is to block the diffusion of doped atoms into the active layer.

[0035] In some optional embodiments, the second spacer layer comprises M groups of material layer pairs formed by alternately stacking a sub-layers, wherein 2≤a≤6, and M≥2. In order to control the thickness of the second spacer layer within a certain range, M≤20 is preferred.

[0036] In this embodiment, taking a as 2 as an example, the second spacer layer 108 includes M groups of material pairs formed by alternating stacking of first sub-layers 108a and second sub-layers 108b. x1 Ga 1-x1 InP or Al y1 Ga 1-y1 As material, the second sublayer is composed of Al x2 Ga 1-x2 InP material or Al y2 Ga 1-y2 As, wherein 0<x1<x2≤1, 0<y1<y2≤1. In some optional embodiments, x2-x1≥0.1 or y2-y1≥0.1 is preferred. This can ensure that adjacent sublayers have a clear phase interface and have a better blocking effect on the diffusion of defects and doping atoms. The thickness of the first sublayer ranges from 0.5 to 100 nm, preferably 1-10 nm; the thickness of the second sublayer ranges from 0.5 to 100 nm, preferably 1-10 nm. The thickness of the second spacer layer is less than 300 nm, preferably less than 250 nm, and more preferably less than 200 nm, thereby increasing the proportion of carriers undergoing radiation recombination in the active layer, thereby achieving an improvement in the internal quantum efficiency and ESD performance of the light-emitting diode.

[0037] In this embodiment, the second spacer layer adopts a material layer pair structure formed by alternating multiple sublayers, and the interfaces between the multiple sublayers can effectively block the diffusion of doping atoms into the active layer, so as to minimize the thickness of the second spacer layer, thereby increasing the proportion of carriers undergoing radiation recombination in the active layer, and realizing the improvement of the internal quantum efficiency and ESD performance of the light-emitting diode.

[0038] In some optional embodiments, the second spacer layer is p-type doped, and the doping concentration is less than 2E17 / cm 3 .

[0039] The second type semiconductor layer includes a second cover layer 109, a second current spreading layer 110 and a second ohmic contact layer 111; wherein the second cover layer 109 is used to provide holes for the active layer 107, and the material is Al z2 Ga 1-z2 InP, where 0<z2≤1, the preferred material is AlInP, with a thickness of 200~1500nm; p-type doping is commonly Mg doping, and doping with other equivalent elements is not excluded.

[0040] The second current spreading layer 110 plays a role in current spreading, and its spreading ability is related to its thickness. Therefore, in this embodiment, its thickness can be selected according to the specific device size, and the preferred thickness is controlled to be above 300nm and below 12000nm. In this embodiment, the thickness of the second current spreading layer 110 is preferably 400~100001000nm. In this embodiment, the preferred material is GaP, and the p-type doping concentration is 6E17~8E18 / cm 3 Common p-type doping is magnesium doping or carbon doping, and equivalent substitution doping of other elements is not excluded.

[0041] The second ohmic contact layer 111 forms an ohmic contact with the second electrode 204. The preferred material is GaP with a doping concentration of 5E19-2E20 / cm 3 , more preferably 1E20 / cm 3 The thickness of the second ohmic contact layer 111 is preferably greater than 40 nm and less than 150 nm. In this embodiment, the thickness of the second ohmic contact layer 111 is preferably 60 nm.

[0042] Figure 2 A schematic diagram of a light emitting diode is shown. Figure 1 The epitaxial structure shown, the light emitting diode is mainly used in outdoor display screens, plant lighting, stage lights, automotive displays and other fields.

[0043] The light emitting diode comprises a substrate 200, the semiconductor epitaxial stack is bonded to the substrate 200 via a bonding layer 201, and the semiconductor epitaxial stack comprises a second ohmic contact layer 111, a second current spreading layer 110, a second cover layer 109, a second spacer layer 108, an active layer 107, a first spacer layer 106, a first cover layer 105, a first current spreading layer 104 and a first ohmic contact layer 103 which are sequentially stacked on the substrate 200. The second spacer layer 108 is a material layer pair formed by alternately stacking a first sublayer 108a and a second sublayer 108b.

[0044] The substrate 200 is a conductive substrate, which may be silicon, silicon carbide or a metal substrate, and the metal substrate is preferably a copper, tungsten or molybdenum substrate. In order to support the semiconductor epitaxial stack with sufficient mechanical strength, the thickness of the substrate 200 is preferably 50 μm or more. In addition, in order to facilitate mechanical processing of the substrate 200 after bonding to the semiconductor epitaxial stack, the thickness of the substrate 200 is preferably not more than 300 μm. In this embodiment, the substrate 200 is preferably a silicon substrate.

[0045] The first ohmic contact layer 103 is provided with a first electrode 203, and an ohmic contact is formed between the first electrode 203 and the first ohmic contact layer 103 to realize current flow. The first ohmic contact layer 103 only retains the part vertically below the first electrode 203. The first current spreading layer 104 includes two parts in the horizontal direction, namely, a part P1 located below the first electrode 203, and a part P2 not located below the first electrode 203 is exposed and defined as a light-emitting surface. The light-emitting surface of the first current spreading layer 104 can be formed around the first electrode 203. In some optional embodiments, the light-emitting surface can be further formed into a pattern surface or a roughened surface by an etching process, wherein the pattern surface can be a pattern obtained by etching. The roughened surface can have a regular surface structure or an arbitrary irregular surface micro-nano structure. The roughened surface or the patterned surface is essentially a light-emitting layer, and the light can escape more easily, thereby improving the light extraction efficiency. Preferably, the light-emitting surface is a roughened surface, and the height difference (or height difference) of the surface structure formed by the roughening is less than 1 micron, preferably 10-300nm.

[0046] The level of the roughened surface of the first current spreading layer 104 is substantially lower than the level of the second surface (interface) located below the first electrode 203 due to the roughening process.

[0047] Specifically, Figure 2As shown, in this embodiment, the first current spreading layer 104 includes a portion P1 located below the first electrode 203 and a portion P2 not located below the first electrode 203. The first current spreading layer 104 has a first thickness t1 in the portion P1 covered by the electrode, and the first current spreading layer 104 not covered by the first electrode has a second thickness t2. Preferably, the first thickness t1 is 1.5 to 2.5 microns, and the second thickness t2 is 0.5 to 1.5 μm. The thickness t1 of the P1 portion is greater than the thickness t2 of the P2 portion. Preferably, the second thickness t2 is less than the first thickness t1 by at least 0.3 μm.

[0048] A reflective structure 202 may be disposed between the semiconductor epitaxial stack and the substrate 200. The reflective structure 202 includes a metal reflective layer 202a and a dielectric material layer 202b. The two cooperate to form an electrical connection with the second type semiconductor layer on the one hand, and to reflect the light beam emitted by the active layer 107 to the light emitting surface of the first current spreading layer 104 or the side wall of the semiconductor epitaxial stack for light emission on the other hand. In some embodiments, a transparent conductive layer (not shown in the figure) is further included between the semiconductor epitaxial stack and the metal reflective layer 202, and the transparent conductive layer forms an ohmic contact with the second ohmic contact layer 111.

[0049] The light emitting diode further comprises a second electrode 204. In some embodiments, the second electrode 204 is located on the back side of the substrate 200. Alternatively, the second electrode 204 is located on the substrate 200, on the same side as the semiconductor epitaxial stack.

[0050] The first electrode 203 and the second electrode 204 include a transparent conductive material and / or a metal material. The transparent conductive material includes a transparent conductive layer, such as ITO or IZO, and the metal material includes at least one of GeAuNi, AuGe, AuZn, Au, Al, Pt, and Ti.

[0051] In this embodiment, the second spacer layer adopts a material layer pair structure formed by alternating multiple sublayers, and the interfaces between the multiple sublayers can effectively block the diffusion of doping atoms into the active layer, so as to minimize the thickness of the second spacer layer, thereby increasing the proportion of carriers undergoing radiation recombination in the active layer, and realizing the improvement of the internal quantum efficiency and ESD performance of the light-emitting diode. Example 2

[0052] Figure 3~Figure 4 A schematic diagram of the manufacturing process of the light emitting diode according to the present embodiment 1 is shown. The manufacturing method of the light emitting diode of the present embodiment is described in detail below in conjunction with the schematic diagram.

[0053] First, see Figure 1, an epitaxial structure is provided, which specifically includes the following steps: providing a growth substrate 100, epitaxially growing a semiconductor epitaxial stack by an epitaxial process such as MOCVD, the semiconductor epitaxial stack including a buffer layer 101 and an etching stop layer 102 sequentially stacked on the surface of the growth substrate 100, for removing the epitaxial growth substrate 100, and then growing a first ohmic contact layer 103, a first current spreading layer 104, a first covering layer 105, a first spacer layer 106, an active layer 107, a second spacer layer 108, a second covering layer 109, a second current spreading layer 110, and a second ohmic contact layer 111. The second spacer layer 108 is a material layer pair formed by alternately stacking a first sublayer 108a and a second sublayer 108b.

[0054] Next, the semiconductor epitaxial stack is transferred to the substrate 200, and the growth substrate 100 is removed to obtain Figure 3 The structure shown specifically includes the following steps: a reflective structure 202 is fabricated on the second ohmic contact layer 111, which includes a metal reflective layer 202a and a dielectric material layer 202b, which cooperate to form an electrical connection with the second type semiconductor layer on the one hand, and on the other hand, are used to reflect the light beam emitted by the active layer 107 to the light-emitting surface of the first current spreading layer 104 or the side wall of the semiconductor epitaxial stack for light emission. In some embodiments, a transparent conductive layer (not shown in the figure) is further included between the semiconductor epitaxial stack and the metal reflective layer 202, and the transparent conductive layer forms an ohmic contact with the second ohmic contact layer 111. Then, a substrate 200 is provided, a metal bonding layer 201 is disposed on the substrate 200, the substrate 201 is bonded to the semiconductor epitaxial stack, and the growth substrate 100 is removed. When the growth substrate 100 is gallium arsenide, it can be removed by a wet etching process until the first ohmic contact layer 103 is exposed.

[0055] Then, if Figure 4 As shown, a first electrode 203 is formed on the first ohmic contact layer 103, and the first electrode 203 forms a good ohmic contact with the first ohmic contact layer 103, and a second electrode 204 is formed on the back side of the substrate 200, whereby conduction current can pass between the first electrode 203, the second electrode 204 and the semiconductor epitaxial stack. The substrate 200 has a certain thickness and can support all the layers thereon.

[0056] Then, a mask is formed to cover the first electrode 203, and the first ohmic contact layer 103 around the first electrode 203 is exposed; an etching process is performed to etch away the first ohmic contact layer 103 around the first electrode 203, so that the ohmic contact layer 103 not located under the first electrode 109 is completely removed, and the first current spreading layer 104 is exposed at the same time, and then the first current spreading layer 104 is etched to form a patterned or roughened surface, forming a Figure 2The removal process of the ohmic contact layer and the roughening process of the first current spreading layer 104 can be a wet etching process of the same step or multiple steps, and the wet etching solution can be an acidic solution, such as hydrochloric acid, sulfuric acid or hydrofluoric acid or citric acid, or any other preferred chemical reagent.

[0057] Finally, according to the size requirements, the unitized invisible light emitting diode is obtained through etching, splitting and other processes.

[0058] In this embodiment, the second spacer layer of the light-emitting diode is configured to include M groups of material layer pairs formed by alternating stacking of a sub-layers, which can enhance the blocking effect of the second spacer layer on the diffusion of doped atoms and defects such as dislocations, thereby minimizing the thickness of the second spacer layer, increasing the proportion of carriers undergoing radiation recombination in the active layer, and achieving improvements in the internal quantum efficiency and ESD performance of the light-emitting diode. Example 3

[0059] Figure 5 A schematic diagram of a light emitting diode in another embodiment is shown. Figure 1 The epitaxial structure shown in FIG. 1 is a flip-chip light-emitting diode, which is mainly used in TVs and panels.

[0060] like Figure 5 As shown, the light emitting diode comprises a substrate 200, and the substrate 200 is a transparent substrate, and in this embodiment, a sapphire substrate is preferably used. The semiconductor epitaxial stack is bonded to the substrate 200 through a bonding layer 201, and the bonding layer 201 is a transparent bonding layer. The semiconductor epitaxial stack comprises a first table S1 and a second table S2, and the table S2 is formed by a recessed second type semiconductor layer; the first electrode 203 and the second electrode 204 comprise an ohmic contact portion 203a of the first electrode and an ohmic contact portion 204a of the second electrode, and a pad electrode 203b of the first electrode and a pad electrode 204b of the second electrode, and the ohmic contact portion 203a of the first electrode and the ohmic contact portion 204a of the second electrode are formed on the first table S1 and the second table S2, respectively forming ohmic contacts with the first type semiconductor layer and the second type semiconductor layer. The surface of the second current spreading layer 110 is formed with a roughened structure, so that the bonding layer 201 is bonded to the surface of the semiconductor epitaxial stack, thereby realizing the bonding of the semiconductor epitaxial stack to the transparent substrate. In this embodiment, the semiconductor epitaxial stack is bonded to the substrate 200 through a bonding layer, and then the growth substrate is removed, and then the first electrode 203 and the second electrode 204 are manufactured.

[0061] In this embodiment, the second spacer layer of the light-emitting diode is configured to include M groups of material layer pairs formed by alternating stacking of a sub-layers, which can enhance the blocking effect of the second spacer layer on the diffusion of doped atoms and defects such as dislocations, thereby minimizing the thickness of the second spacer layer, increasing the proportion of carriers undergoing radiation recombination in the active layer, and achieving improvements in the internal quantum efficiency and ESD performance of the light-emitting diode. Example 4

[0062] Figure 6 A schematic diagram of a light emitting diode in another embodiment is shown. Figure 1 The epitaxial structure shown. In this embodiment, the light emitting diode is a micro light emitting diode, and the current density of the micro light emitting diode is less than 10A / cm 3 , more preferably the current density is less than 5A / cm 3 The micro-LED is mainly used in TV, panel, vehicle display, wearable and other fields. The size of the micro-LED is preferably less than or equal to 50 μm, that is, the length of at least one side of the micro-LED is less than or equal to 50 μm.

[0063] The micro-light emitting diode described in this embodiment includes: a semiconductor epitaxial stack, including a first type semiconductor layer, a second type semiconductor layer and an active layer 107 located between the first type semiconductor layer and the second type semiconductor layer; a first table S1, which is composed of the first type semiconductor layer exposed by the depression of the semiconductor epitaxial stack, and a second table S2, which is composed of the second type semiconductor layer; a first electrode 203, which is formed on the first table S1 and is electrically connected to the first type semiconductor layer; a second electrode 204, which is formed on the second table S2 and is electrically connected to the second type semiconductor layer.

[0064] In this embodiment, the first type semiconductor layer includes a first current spreading layer 104, a first covering layer 105 and a first spacer layer 106; wherein the first current spreading layer 104 plays a role in current spreading, and its spreading ability is related to its thickness. In this embodiment, the preferred material is Al u1 Ga 1-u1 InP, thickness 2500~5000nm, the n-type doping concentration is 2E17~5E18 / cm 3 .Al u1 Ga 1-u1In InP, u1 is between 0.3 and 1, which can ensure the light transmittance of the n-type current spreading layer. The n-type current spreading layer 104 is in ohmic contact with the first electrode 203 to form an electrical connection; the first current spreading layer 104 provides a light-emitting surface on the side away from the active layer. The function of the first covering layer 105 is to provide electrons for MQW. The preferred material is AlInP with a thickness of 200 to 1200 nm. The common n-type doping is Si doping, and other elements are not excluded. The first spacer layer 106 is located between the first covering layer 105 and the active layer 107. The preferred material is Al a1 Ga 1-a1 InP, the thickness of the first spacer layer 106 is preferably 0-50nm, preferably 0-20nm. The Al component content a1 ranges from 0.2 to 1; the doping concentration is lower than 21E17 / cm 3 .

[0065] The second type semiconductor layer includes a second spacer layer 108 , a second cover layer 109 , a second current spreading layer 110 and a second ohmic contact layer 111 ; the second spacer layer 108 is located between the active layer 107 and the second cover layer 109 .

[0066] In this embodiment, the second spacer layer 108 preferably includes M groups of material pairs formed by alternately stacking first sub-layers 108a and second sub-layers 108b, wherein 2≤M≤20. x1 Ga 1-x1 InP or Al y1 Ga 1-y1 As material, the second sublayer is composed of Al x2 Ga 1-x2 InP material or Al y2 Ga 1-y2 As, wherein 0<x1<x2≤1, 0<y1<y2≤1. In some optional embodiments, preferably x2-x1≥0.1 or y2-y1≥0.1. The thickness of the first sublayer ranges from 0.5 to 100 nm, preferably 1-10 nm; the thickness of the second sublayer ranges from 0.5 to 100 nm, preferably 1-10 nm. The thickness of the second spacer layer is less than 300 nm. In this embodiment, the second spacer layer adopts a material layer pair structure formed by alternating stacking of multiple sublayers, and the interface between the multiple sublayers can effectively block the diffusion of doped atoms into the active layer, so that the thickness of the second spacer layer can be minimized, thereby increasing the proportion of carriers undergoing radiation recombination in the active layer, and realizing the improvement of the internal quantum efficiency and ESD performance of the light-emitting diode.

[0067] In some optional embodiments, the second spacer layer is p-type doped, and the doping concentration is less than 2E17 / cm 3 .

[0068] The function of the second covering layer 109 is to provide holes for the active layer, and the preferred material is AlInP with a thickness of 200-1200 nm. The common P-type doping is Mg doping, and other equivalent elements are not excluded.

[0069] The second current spreading layer 110 plays the role of current spreading, and its spreading ability is related to its thickness. Therefore, in this embodiment, its thickness can be selected according to the specific device size, and the preferred thickness is controlled to be above 200nm and below 1500nm. In this embodiment, the thickness of the second current spreading layer 110 is preferably 300~1000nm. In this embodiment, the preferred material is GaP, and the p-type doping concentration is 6E17~8E18 / cm 3 , p-type doping is commonly done with Mg or C doping, and equivalent substitutions of other elements are not excluded.

[0070] The second ohmic contact layer 111 covers the second current spreading layer 110, and the preferred material is Gap, with a thickness of 30-100 nm and a doping concentration of 5E19-2E20 / cm 3 , the preferred doping concentration is 1E20 / cm 3 A good ohmic contact can be formed with the second electrode 204. The second ohmic contact layer 111 is in ohmic contact with the second electrode 204 to form an electrical connection.

[0071] The active layer 107 is a multi-quantum well, made of Al m Ga 1-m InP / Al n Ga 1-n InP (0≤m≤n≤1) repeatedly stacked well and barrier structure. In this embodiment, the number of periods of the quantum well structure is 2 to 20, preferably 2 to 15, the thickness of the well layer is 3 to 7 nm, and the thickness of the barrier layer is 4 to 8 nm.

[0072] The conductive metal of the first electrode 203 in contact with the first type semiconductor layer can be selected from gold, platinum or silver, or a transparent conductive oxide, specifically ITO, ZnO, etc.; more preferably, the first electrode 203 can be a multilayer material, such as an alloy material including at least one of gold germanium nickel, gold beryllium, gold germanium, gold zinc, etc. More preferably, the first electrode 203 can also include a reflective metal, such as gold or silver, to reflect part of the light radiated from the active layer and penetrating the current spreading layer 104 of the first type semiconductor layer back to the semiconductor epitaxial stack and emit light from the light output side.

[0073] In order to form a good ohmic contact with the second ohmic contact layer 111 of the second type semiconductor layer, the second electrode 204 is preferably made of a conductive metal such as gold, platinum or silver. More preferably, the second electrode 204 may include a multilayer material, including at least one alloy material of gold germanium nickel, gold beryllium, gold germanium, gold zinc, etc. More preferably, in order to improve the ohmic contact effect between the second electrode 204 and one side of the second ohmic contact layer 111, at least one metal that can diffuse to one side of the second ohmic contact layer 111 may be included to improve the ohmic contact resistance. In order to promote diffusion, a fusion of at least 300°C may be selected. The diffused metal is a metal that can directly contact one side of the second ohmic contact layer 111, such as gold, platinum or silver.

[0074] In order to improve the reliability of the micro-LED, an insulating protective layer 207 (not shown in the figure) is provided on the first table S1, the second table S2 and the side wall of the micro-LED. The insulating protective layer is a single-layer or multi-layer structure, and is composed of SiO2, SiN x , Al2O3, Ti3O5. In some optional embodiments, the insulating protection layer 207 is a Bragg reflection layer structure, for example, the insulating protection layer 207 is formed by alternating stacking of Ti3O5 and SiO2. In this embodiment, the insulating protection layer 207 can be made of SiNx or SiO2, with a thickness of more than 1 μm.

[0075] In this embodiment, the first electrode 203 and the second electrode 204 are located on the opposite side of the light-emitting side, and the first electrode 203 and the second electrode 204 can be in contact with the external electrical connection through the opposite side of the light-emitting side to form a flip-chip structure. Therefore, the first electrode 203 and the second electrode 204 include the ohmic contact portion 203a of the first electrode and the ohmic contact portion 203a of the second electrode and the pad electrode 203b of the first electrode and the pad electrode 203b of the second electrode. The pad electrode 203b of the first electrode and the pad electrode 203b of the second electrode can be at least one layer such as gold, aluminum or silver to achieve the solid crystal of the first electrode 203 and the second electrode 204. The first electrode 203 and the second electrode 204 can be of equal height or unequal height, and the pad metal layers of the first electrode and the second electrode do not overlap in the thickness direction.

[0076] Figure 7This is a schematic diagram of a micro-luminescent element formed using the micro-luminescent diode of this embodiment. The micro-luminescent element also includes a base frame 250 for supporting the micro-luminescent diode. The base frame 250 is located at the lower side of the micro-luminescent diode and is used to connect the micro-luminescent diode and the bridge arm 240 of the base frame 250. The base frame 250 includes a substrate 200 and a bonding layer 201. In this embodiment, the material of the bonding layer 201 is BCB glue, silica gel, UV glue or resin, and the material of the bridge arm 240 includes dielectric, metal or semiconductor material. In some embodiments, the horizontal portion 2071 of the insulating protective layer 207 can be used as the bridge arm 240, bridging the bonding layer 201 to connect the micro-luminescent diode and the base frame 250.

[0077] The micro-LED is separated from the base frame 250 by printing stamp transfer, and the printing stamp material is PDMS, silicone, pyrolytic glue or UV ultraviolet glue. In some cases, there is a sacrificial layer 208 between the micro-LED and the base frame, and at least in certain cases, the removal efficiency of the sacrificial layer 208 is higher than that of the micro-LED, and the certain cases include chemical decomposition or physical decomposition, such as ultraviolet light decomposition, etching removal or impact removal. Example 5

[0078] Figure 8~Figure 14 A schematic diagram of the manufacturing process of the micro light emitting diode in this embodiment 4 is shown. The manufacturing method of the micro light emitting diode in this embodiment is described in detail below in conjunction with the schematic diagram.

[0079] First, if Figure 8 As shown, an epitaxial structure is provided, which specifically includes the following steps: providing a growth substrate 100, epitaxially growing a semiconductor epitaxial stack by an epitaxial process such as MOCVD, the semiconductor epitaxial stack including a buffer layer 101 and an etching stop layer 102 sequentially stacked on the surface of the growth substrate 100, for removing the epitaxial growth substrate 100, and then growing a first current spreading layer 104, a first covering layer 105, a first spacer layer 106, an active layer 107, a second spacer layer 108, a second covering layer 109, a second current spreading layer 110, and a second ohmic contact layer 111. The second spacer layer 108 is a material layer pair formed by alternately stacking a first sublayer 108a and a second sublayer 108b.

[0080] Then, see Fig. 9 , a portion of the semiconductor epitaxial stack is removed by dry etching to form a first mesa S1 and a second mesa S2, wherein the first mesa S1 is composed of a first type semiconductor layer exposed by the depression of the semiconductor epitaxial stack, and the second mesa S2 is composed of a second type semiconductor layer; a side wall is formed, which is located at the outer edge of the semiconductor epitaxial stack and between the first mesa S1 and the second mesa S2.

[0081] Next, see Fig.10, respectively make the first electrode 203 and the second electrode 204 on the first table S1 and the second table S2; wherein the first electrode 203 and the second electrode 204 include ohmic contact parts 203a and 204a, the ohmic contact parts are covered with an insulating protective layer 207, and pad electrodes 203b and 204b are formed on the insulating protective layer 207 to contact the ohmic contact parts 203a and 204a respectively. The material of the ohmic contact parts 203a and 204a can be, for example, Au / AuZn / Au. In this step, the ohmic contact parts 203a and 204a can be fused to form a good ohmic contact with the semiconductor epitaxial stack. The insulating protective layer 207 is preferably made of SiNx or SiO2, and the thickness is more than 1μm. In other optional embodiments, the insulating protective layer 207 can adopt a Bragg reflection layer structure, which is formed by alternating stacking of two materials with different refractive indices.

[0082] Next, see Fig.11 , a sacrificial layer 208 is covered on the surface of the micro light emitting diode; preferably, the thickness of the sacrificial layer 208 covering the sidewall is greater than 1 μm, and the material of the sacrificial layer 208 can be oxide, nitride or a material that can be selectively removed relative to other layers.

[0083] Next, see Fig.12 , bonding glue, such as BCB glue, on the sacrificial layer 208 of the micro light emitting diode to form a bonding layer 201; Next, see Fig.13 , bonding the wafer with distributed micro-LEDs to the substrate 200 .

[0084] Next, see Fig.14 , peeling off the growth substrate 100 , removing the buffer layer 101 and the etching stop layer 102 .

[0085] Next, the first type semiconductor layer at the edge of the micro-LED is removed by masking and etching, and the etching stops on the insulating protection layer 207 to form an independent core particle, which is convenient for the subsequent separation of the core particles. Figure 8 The micro-light emitting diodes shown.

[0086] Finally, the formed micro-LED is separated from the substrate 210 and transferred to the packaging substrate by transfer printing. (Not shown in the figure) Example 6

[0087] Fig.15 is a schematic diagram of a light emitting diode epitaxial structure according to another embodiment, and Figure 1 Compared with the epitaxial structure of the present embodiment, the first spacer layer 106 in this embodiment is a third sub-layer 106a and a fourth sub-layer 106b alternately stacked in N groups of material pairs, where 2≤N≤20. The third sub-layer is Alx3 Ga 1-x3 InP or Al y3 Ga 1-y3 As material, the fourth sublayer is composed of Al x4 Ga 1-x4 InP material or Al y4 Ga 1-y4 As, wherein 0<x3<x4≤1, 0<y3<y4≤1. In some optional embodiments, preferably x4-x3≥0.1 or y4-y3≥0.1. The thickness of the third sublayer ranges from 0.5 to 100 nm, preferably from 1 to 10 nm; the thickness of the fourth sublayer ranges from 0.5 to 100 nm, preferably from 1 to 10 nm. The thickness of the first spacer layer 106 is less than 300 nm, preferably less than 250 nm, and more preferably less than 200 nm.

[0088] In some optional embodiments, the first spacer layer is n-type doped, and the doping concentration is less than 2E17 / cm 3 .

[0089] Fig.16a , 16b and 16c are used Fig.15 The light-emitting diode formed by the epitaxial structure is Figure 2 , Figure 5 and Figure 6 Compared with LEDs, Fig.16a , the first spacer layer 106 of the light emitting diode in 16b and 16c is an N group of material pairs formed by the alternating stacking of the third sublayer 106a and the fourth sublayer 106b. In this embodiment, the first spacer layer and the second spacer layer of the light emitting diode are both material layer pairs formed by the alternating stacking of multiple sublayers, which can enhance the blocking effect of the first spacer layer and the second spacer layer on the diffusion of doping atoms and defects such as dislocations, thereby minimizing the thickness of the first spacer layer and the second spacer layer, and increasing the proportion of carriers undergoing radiation recombination in the active layer, thereby achieving the improvement of the internal quantum efficiency and ESD performance of the light emitting diode. Example 7

[0090] Fig.17 is another epitaxial structure in this embodiment, and Figure 1 Compared with the epitaxial structure of the embodiment, the second spacer layer 108 in this embodiment is a multilayer structure formed by stacking m sub-layers formed of different materials, where m≥2. Fig.17As shown, the second spacer layer comprises A1, A...Am, and the materials of each layer of A1, A2...Am are different, and the materials of the m sublayers are selected from AlGaInP or AlGaAs-based materials. The thickness of each sublayer ranges from 0.5 to 100 nm, preferably from 1 to 10 nm. The thickness of the second spacer layer is less than 300 nm, preferably less than 250 nm, and more preferably less than 200 nm, so as to increase the proportion of carriers radiating and recombining in the active layer, thereby achieving the improvement of the internal quantum efficiency and ESD performance of the light-emitting diode.

[0091] Fig.18a , 18b and 18c are used Fig.17 The light-emitting diode formed by the epitaxial structure is Figure 2 , Figure 5 and Figure 6 Compared with LEDs, Fig.18a The second spacer layer 108 of the light-emitting diode in 18b and 18c is a multilayer structure formed by stacking m sublayers formed of different materials. The interface formed by the sublayers of different materials in the second spacer layer can effectively block the diffusion of doping atoms and defects, enhance the blocking effect of the second spacer layer on the diffusion of doping atoms and defects such as dislocations, thereby minimizing the thickness of the second spacer layer and increasing the proportion of carriers undergoing radiation recombination in the active layer, thereby achieving an improvement in the internal quantum efficiency and ESD performance of the light-emitting diode.

[0092] In some embodiments, the first spacer layer 106 of the light-emitting diode is a multilayer structure formed by stacking n sublayers formed of different materials, where n≥2. (Not shown in the figure) The first spacer layer 106 includes B1, B2...Bm sublayers, each of which is made of different materials, and the materials of the m sublayers are selected from AlGaInP or AlGaAs-based materials. The thickness of each sublayer ranges from 0.5 to 100 nm, preferably from 1 to 10 nm.

[0093] In some embodiments, the first and second spacer layers of the light-emitting diode are both multilayer structures formed by stacking sublayers of different materials. This design can utilize the interface between the first spacer layer and the second spacer layer to effectively block the diffusion of doping atoms, enhance the blocking effect of the first spacer layer and the second spacer layer on the diffusion of doping atoms and defects such as dislocations, thereby minimizing the thickness of the first spacer layer and the second spacer layer, and increasing the proportion of carriers undergoing radiation recombination in the active layer, thereby achieving an improvement in the internal quantum efficiency and ESD performance of the light-emitting diode. Example 8

[0094] This embodiment provides a light emitting device 300, which includes a driving unit and a light emitting diode, wherein the driving unit is electrically connected to the light emitting diode. Fig.19The light emitting device 300 includes a plurality of light emitting diodes arranged in an array as in any of the above embodiments. Fig.19 FIG. 1 schematically shows a portion of a light emitting diode 1 in an enlarged manner.

[0095] In the light-emitting diode and the light-emitting device of the embodiments of the present invention, the second spacer layer and / or the first spacer layer are arranged to be a multilayer structure formed by stacking two or more sublayers of different materials, which can enhance the blocking effect of the second spacer layer and / or the first spacer layer on the diffusion of doping atoms and defects such as dislocations, thereby minimizing the thickness of the second spacer layer and / or the first spacer layer, increasing the proportion of carriers undergoing radiation recombination in the active layer, and achieving an improvement in the internal quantum efficiency and ESD performance of the light-emitting diode.

[0096] It should be noted that the above implementation modes are only used to illustrate the present invention, and are not used to limit the present invention. Those skilled in the art can make various modifications and changes to the present invention without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the present invention. The scope of patent protection of the present invention should be limited to the scope of the claims.

Claims

1. Light emitting diodes, including: A semiconductor epitaxial stack having a first surface and a second surface opposite to each other, comprising a first type semiconductor layer, an active layer and a second type semiconductor layer stacked in sequence from the first surface to the second surface; a first spacer layer is included between the first type semiconductor layer and the active layer; and a second spacer layer is included between the second type semiconductor layer and the active layer; The feature of the invention is that the second spacer layer is a multilayer structure formed by stacking sublayers formed by two or more materials.

2. The light emitting diode according to claim 1, characterized in that: The second spacer layer includes M groups of material layer pairs formed by alternately stacking a sub-layers, wherein 2≤a≤6, 2≤M≤20.

3. The light emitting diode according to claim 2, characterized in that: The a is 2, and the second spacer layer includes M groups of material layer pairs formed by alternately stacking first sub-layers and second sub-layers.

4. The light emitting diode according to claim 3, characterized in that: The first sublayer is composed of Al x1 Ga 1-x1 InP or Al y1 Ga 1-y1 As material, the second sublayer is composed of Al x2 Ga 1-x2 InP material or Al y2 Ga 1-y2 As, wherein 0<x1<x2≤1, 0<y1<y2≤1.

5. The light emitting diode according to claim 4, characterized in that: x2-x1≥0.1 or y2-y1≥0.

1.

6. The light emitting diode according to claim 4, characterized in that: The thickness of the first sublayer is in the range of 0.5-100 nm, and the thickness of the second sublayer is in the range of 0.5-100 nm.

7. The light emitting diode according to claim 1, characterized in that: The second spacer layer is p-type doped, and the doping concentration is less than 2E17 / cm 3 .

8. The light emitting diode according to claim 1, characterized in that: The thickness of the second spacer layer is less than 300 nm.

9. The light emitting diode according to claim 1, characterized in that: The second spacer layer is a multilayer structure formed by stacking m sublayers formed of different materials, where m≥2.

10. The light emitting diode according to claim 9, characterized in that: The materials of the m sub-layers are selected from AlGaInP or AlGaAs-based materials.

11. The light emitting diode according to claim 1, characterized in that: The first spacer layer is a multilayer structure formed by stacking sublayers formed by two or more materials.

12. The light emitting diode according to claim 11, characterized in that: The first spacer layer includes N groups of material layer pairs formed by alternately stacking b sub-layers, wherein 2≤b≤6, 2≤N≤20.

13. The light emitting diode according to claim 12, characterized in that: The b is 2, and the first spacer layer includes N groups of material layer pairs formed by alternately stacking the third sub-layer and the fourth sub-layer.

14. The light emitting diode according to claim 13, characterized in that: The third sublayer is made of Al x3 Ga 1-x3 InP or Al y3 Ga 1-y3 As material, the fourth sublayer is composed of Al x4 Ga 1-x4 InP material or Al y4 Ga 1-y4 As, wherein 0<x3<x4≤1, 0<y3<y4≤1.

15. The light emitting diode according to claim 14, characterized in that: x4-x3≥0.1 or y4-y3≥0.

1.

16. The light emitting diode according to claim 14, characterized in that: The thickness of the third sublayer is in the range of 0.5-100 nm, and the thickness of the fourth sublayer is in the range of 0.5-100 nm.

17. The light emitting diode according to claim 11, characterized in that: The first spacer layer is n-type doped, and the doping concentration is less than 2E17 / cm 3 .

18. The light emitting diode according to claim 11, characterized in that: The thickness of the first spacer layer is less than 300 nm.

19. The light emitting diode according to claim 11, characterized in that: The first spacer layer is a multilayer structure formed by stacking n sublayers formed of different materials, where n≥2.

20. The light emitting diode according to claim 19, characterized in that: The materials of the n sub-layers are selected from AlGaInP or AlGaAs-based materials.

21. The light emitting diode according to claim 1, characterized in that: The active layer radiates light with a wavelength of 550-950nm.

22. A light emitting device, characterized in that: A light emitting diode comprising any one of claims 1 to 21.

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