Light emitting diode and light emitting device

Abstract

The invention relates to the technical field of semiconductor manufacturing, in particular to a light-emitting diode, which comprises a semiconductor lamination layer, a first connecting electrode, a second connecting electrode, a first electrode, a second electrode, an insulating layer, a first bonding pad and a second bonding pad, and is characterized in that the semiconductor lamination layer comprises a first semiconductor layer, a light-emitting layer and a second semiconductor layer which are laminated in sequence; the first connecting electrode is connected with the first semiconductor layer, the second connecting electrode is connected with the second semiconductor layer, the first electrode is connected with the first connecting electrode, the second electrode is connected with the second connecting electrode, the insulating layer covers the semiconductor laminated layer, the first bonding pad is connected with the first electrode, and the second bonding pad is connected with the second electrode. The second electrode comprises a starting electrode and a plurality of extending electrodes, the extending electrodes are connected with the starting electrode and extend in the direction away from the starting electrode, and the second openings are formed in the tail ends of the extending electrodes. Therefore, current congestion of the light-emitting diode can be avoided, and the light-emitting uniformity of the light-emitting diode is improved.

Description

Technical Field

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

[0002] Light Emitting Diode (LED) is a semiconductor light-emitting element, usually made of semiconductors such as GaN, GaAs, GaP, GaAsP, etc., and its core is a PN junction with light-emitting characteristics. LED has the advantages of high luminous intensity, high efficiency, small size, and long service life, and is considered to be one of the most promising light sources at present. LED has been widely used in lighting, monitoring and command, high-definition broadcasting, high-end cinemas, office displays, conference interaction, virtual reality and other fields.

[0003] UV-LED (UV Light Emitting Diode) is a solid-state semiconductor device that can directly convert electrical energy into ultraviolet light. In recent years, the huge application value of UV LED, especially deep ultraviolet LED, has attracted great attention and become a new research hotspot. At present, traditional deep ultraviolet LED has problems of current congestion and poor uniformity of light emission. Therefore, how to solve this problem has become one of the technical problems that technicians in this field need to solve urgently.

[0004] It should be noted that the information disclosed in this background technology section is only intended to increase the understanding of the overall background of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes prior art already known to a person skilled in the art. Summary of the invention

[0005] The present invention provides a light-emitting diode, which includes a semiconductor stack, a first connecting electrode, a second connecting electrode, a first electrode, a second electrode, an insulating layer, a first pad, and a second pad. The semiconductor stack includes a first semiconductor layer, a light-emitting layer, and a second semiconductor layer stacked in sequence. The first connecting electrode is arranged on the semiconductor stack and electrically connected to the first semiconductor layer. The second connecting electrode is arranged on the semiconductor stack and electrically connected to the second semiconductor layer. The first electrode is connected to the first connecting electrode. The second electrode is connected to the second connecting electrode. The insulating layer covers the semiconductor stack, the first electrode, and the second electrode, and the insulating layer has a first opening and a second opening. The first pad is arranged on the insulating layer and electrically connected to the first electrode through the first opening. The second pad is arranged on the insulating layer and electrically connected to the second electrode through the second opening. Wherein, looking down from the top of the light-emitting diode toward the semiconductor stack, the second electrode includes a starting electrode and a plurality of extension electrodes, the extension electrode is connected to the starting electrode and extends in a direction away from the starting electrode, and the second opening is arranged at the end of the extension electrode.

[0006] The present invention also provides a light-emitting diode, which includes a semiconductor stack, a first connection electrode, a second connection electrode, a first electrode, a second electrode, an insulating layer, a first pad, and a second pad. The semiconductor stack includes a first semiconductor layer, a light-emitting layer, and a second semiconductor layer stacked in sequence. The first connection electrode is arranged on the semiconductor stack and electrically connected to the first semiconductor layer. The second connection electrode is arranged on the semiconductor stack and electrically connected to the second semiconductor layer. The first electrode is connected to the first connection electrode. The second electrode is connected to the second connection electrode. The insulating layer covers the semiconductor stack, the first electrode, and the second electrode, and the insulating layer has a first opening and a second opening. The first pad is arranged on the insulating layer and electrically connected to the first electrode through the first opening. The second pad is arranged on the insulating layer and electrically connected to the second electrode through the second opening. Wherein, looking down from the top of the light-emitting diode toward the semiconductor stack, the second electrode includes a plurality of extended electrodes, the extended electrode has a first end and a second end, the extended electrode extends from the first end to the second end, the first ends of the plurality of extended electrodes are connected to each other, the second ends of the plurality of extended electrodes have a fourth spacing, and the second opening does not overlap with the first end.

[0007] The present invention also provides a light emitting device, which includes a light emitting diode. The light emitting diode is any one of the light emitting diodes provided above.

[0008] An embodiment of the present invention provides a light-emitting diode and a light-emitting device, which avoids current congestion at the connection between the starting electrode and the extended electrode by setting the second opening near the end of the extended electrode, so that the light-emitting diode emits light more evenly and improves the light-emitting characteristics of the light-emitting diode.

[0009] Other features and beneficial effects of the present invention will be described in the following description, and some of the technical features and beneficial effects can be obviously derived from the description or understood by implementing the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, some of the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0011] Figure 1 It is a schematic diagram of the top view structure of a traditional light emitting diode; Figure 2 is a schematic diagram of a top view of a light emitting diode provided in a first embodiment of the present invention; Figure 3 yes Figure 2A schematic diagram of the cross-sectional structure taken along the interception line AA; Figures 4 to 9 is a schematic diagram of the structure of the light emitting diode of the first embodiment at various stages in the manufacturing process; Fig.10 is a schematic diagram of a top view of a light emitting diode provided in a second embodiment of the present invention; Fig.11 is a schematic diagram of a top view of a light emitting diode provided in a third embodiment of the present invention; Fig.12 is a schematic diagram of a top view of a light emitting diode provided in a fourth embodiment of the present invention; Fig.13 It is a schematic diagram of the top structure of a light emitting diode provided in the fifth embodiment of the present invention.

[0012] Reference numerals: 10-substrate; 12-semiconductor stack; 121-first semiconductor layer; 122-light-emitting layer; 123-second semiconductor layer; 21-first connecting electrode; 22-second connecting electrode; 31-first electrode; 311-ring electrode; 312-strip electrode; 32-second electrode; 321-starting electrode; 322-extending electrode; 323-first end; 324-second end; 325-end; 40-insulating layer; 401-first opening; 402-second opening; 41-first soldering pad; 42-second soldering pad; 50-raised area; 60-groove; L1-first spacing; L2-second spacing; L3-third spacing; L4-fourth spacing; S1, S2, S3-lateral length. DETAILED DESCRIPTION

[0013] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions 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, rather than all the embodiments; the technical features designed in different implementation modes of the present invention described below can be combined with each other as long as they do not conflict with each other; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0014] In the description of the present invention, it should be understood that the terms "center", "lateral", "up", "down", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more. In addition, the term "including" and any variation thereof all mean "at least including".

[0015] The present invention provides a light-emitting diode, which includes a semiconductor stack, a first connection electrode, a second connection electrode, a first electrode, a second electrode, an insulating layer, a first pad, and a second pad. The semiconductor stack includes a first semiconductor layer, a light-emitting layer, and a second semiconductor layer stacked in sequence. The first connection electrode is arranged on the semiconductor stack and electrically connected to the first semiconductor layer. The second connection electrode is arranged on the semiconductor stack and electrically connected to the second semiconductor layer. The first electrode is connected to the first connection electrode. The second electrode is connected to the second connection electrode. The insulating layer covers the semiconductor stack, the first electrode, and the second electrode, and the insulating layer has a first opening and a second opening. The first pad is arranged on the insulating layer and electrically connected to the first electrode through the first opening. The second pad is arranged on the insulating layer and electrically connected to the second electrode through the second opening. Among them, looking down from the top of the light-emitting diode toward the semiconductor stack, the second electrode includes a starting electrode and a plurality of extension electrodes, the extension electrode is connected to the starting electrode and extends in a direction away from the starting electrode, and the second opening is arranged at the end of the extension electrode. The present invention avoids current congestion at the connection between the starting electrode and the extension electrode by arranging the second opening near the end of the extension electrode, thereby improving the light uniformity of the light-emitting diode.

[0016] In some embodiments, when looking down from the top of the light emitting diode toward the semiconductor stack, there is a first distance between the ends of two adjacent extended electrodes, thereby ensuring that the ends of the extended electrodes below the second opening are disconnected, thereby preventing current from being confined near the second opening.

[0017] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack, there is a second spacing between the second connection electrodes located below the ends of two adjacent extension electrodes, thereby further avoiding current confinement near the second opening and causing current congestion.

[0018] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack, there is a third spacing between the second semiconductor layers located below two adjacent extension electrode ends, so that the second semiconductor layers located at the extension electrode ends are disconnected to enhance the current spreading performance.

[0019] In some embodiments, when looking down at the semiconductor stack from above the light-emitting diode, the second semiconductor layers located below the ends of two adjacent extended electrodes are connected to each other. In order to improve the light-emitting efficiency, the second semiconductor layer can be appropriately thinned to reduce light absorption, and by retaining a larger area of ​​the second semiconductor layer, the lateral current expansion capability is ensured while the second semiconductor layer is thinned, thereby avoiding voltage increase.

[0020] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack, the end of the extended electrode has a raised area, and the raised area is raised toward the extended electrode adjacent to the extended electrode where the raised area is located. In this way, more area of ​​the second semiconductor layer is reserved, and the lateral current expansion capability is ensured while the second semiconductor layer is thinned.

[0021] In some embodiments, looking down from the top of the light-emitting diode toward the semiconductor stack, the first electrode includes a ring electrode and a strip electrode, the ring electrode is arranged around the second electrode, the strip electrode is connected to the ring electrode and extends toward the starting electrode, the strip electrode is located between two adjacent extension electrodes, and at least part of the first opening is arranged at the end of the strip electrode. Due to the reduction in lateral expansion capability and the high Al component of the deep ultraviolet LED, the contact voltage will increase, and the voltage can be effectively reduced by setting the ring electrode and the strip electrode.

[0022] In some embodiments, looking down toward the semiconductor stack from above the light-emitting diode, the first electrode includes a ring electrode and a strip electrode, the ring electrode is arranged around the second electrode, the strip electrode is located between two adjacent extended electrodes, the strip electrode and the ring electrode are arranged at intervals, and at least part of the first opening is arranged at one end of the strip electrode close to the starting electrode.

[0023] By arranging the first opening at the non-connected position between the strip electrode and the ring electrode, current congestion on the first electrode side can also be avoided, thereby further improving the light emission uniformity of the light emitting diode.

[0024] In some embodiments, at least part of the first opening is disposed on the annular electrode, thereby further improving the light uniformity of the first electrode side and thus improving the light emitting characteristics of the light emitting diode.

[0025] The present invention also provides a light-emitting diode, which includes a semiconductor stack, a first connection electrode, a second connection electrode, a first electrode, a second electrode, an insulating layer, a first pad, and a second pad. The semiconductor stack includes a first semiconductor layer, a light-emitting layer, and a second semiconductor layer stacked in sequence. The first connection electrode is arranged on the semiconductor stack and electrically connected to the first semiconductor layer. The second connection electrode is arranged on the semiconductor stack and electrically connected to the second semiconductor layer. The first electrode is connected to the first connection electrode. The second electrode is connected to the second connection electrode. The insulating layer covers the semiconductor stack, the first electrode, and the second electrode, and the insulating layer has a first opening and a second opening. The first pad is arranged on the insulating layer and electrically connected to the first electrode through the first opening. The second pad is arranged on the insulating layer and electrically connected to the second electrode through the second opening. Wherein, looking down from the top of the light-emitting diode toward the semiconductor stack, the second electrode includes a plurality of extended electrodes, the extended electrode has a first end and a second end, the extended electrode extends from the first end to the second end, the first ends of the plurality of extended electrodes are connected to each other, the second ends of the plurality of extended electrodes have a fourth spacing, and the second opening does not overlap with the first end. By arranging the second opening at a position which does not overlap with the first end of the connection, current congestion at the first end is avoided, so that the light emitting diode emits light more evenly.

[0026] In some embodiments, the second opening is disposed at the second end of the extended electrode. Furthermore, by disposing the second opening at the second end of the extended electrode, current congestion at the first end of the connection is further avoided, thereby improving the light uniformity of the light emitting diode.

[0027] In some embodiments, when looking down from the top of the light emitting diode toward the semiconductor stack, there is a second spacing between the second connection electrodes located below the second ends of two adjacent extension electrodes, thereby ensuring that the electrode below the second opening is disconnected, thereby preventing current from being confined near the second opening.

[0028] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack, there is a third spacing between the second semiconductor layers located below the second ends of two adjacent extended electrodes, so that the second semiconductor layers located at the ends of the extended electrodes are disconnected to enhance the current spreading performance.

[0029] In some embodiments, looking down from the top of the light-emitting diode toward the semiconductor stack, the first electrode includes a ring electrode and a strip electrode, the ring electrode is arranged around the second electrode, the strip electrode is connected to the ring electrode and extends toward the first end of the extension electrode, the strip electrode is located between two adjacent extension electrodes, and at least part of the first opening overlaps with the end of the strip electrode. Due to the reduction in lateral expansion capability and the high Al component of the deep ultraviolet LED, the contact voltage will increase. By setting the ring electrode and the strip electrode, the voltage can be effectively reduced.

[0030] In some embodiments, looking down from the top of the light-emitting diode toward the semiconductor stack, the first electrode includes a ring electrode and a strip electrode, the ring electrode is arranged around the second electrode, the strip electrode is located between two adjacent extended electrodes, the strip electrode and the ring electrode are arranged at intervals, and at least part of the first opening is arranged at a position where the strip electrode is close to the first end of the extended electrode. By arranging the first opening at a non-connected portion between the strip electrode and the ring electrode, current congestion on the first electrode side can also be avoided, further improving the light uniformity of the light-emitting diode.

[0031] In some embodiments, the thickness of the second semiconductor layer is in the range of 1 to 100 nm. By appropriately thinning the second semiconductor layer, epitaxial light absorption is reduced, thereby improving luminous efficiency.

[0032] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack, the contact area between the second connection electrode and the second semiconductor layer accounts for at least 40% of the area of ​​the light-emitting diode. By increasing the area of ​​the second connection electrode, on the one hand, the lateral current expansion capability can be increased and the voltage can be reduced; on the other hand, the current density can be reduced and the aging stability can be improved.

[0033] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack, the area of ​​the second semiconductor layer accounts for at least 50% of the area of ​​the light-emitting diode. By increasing the area of ​​the second semiconductor layer, on the one hand, the light brightness can be improved, and on the other hand, it is beneficial to increase the contact area of ​​the second connecting electrode and improve performance. Through the design of the present invention, more area of ​​the second semiconductor layer can be retained, so as to achieve the lateral current expansion capability and avoid voltage increase while thinning the second semiconductor layer.

[0034] In some embodiments, the light emitting diode is an ultraviolet light emitting diode.

[0035] The present invention also provides a light emitting device, which includes a light emitting diode. The light emitting diode is any one of the light emitting diodes provided above.

[0036] Embodiment 1 See also Figures 1 to 3 , Figure 1 This is a top view of the structure of a traditional light-emitting diode. Figure 2 is a schematic diagram of a top view of a light emitting diode provided in a first embodiment of the present invention, Figure 3 yes Figure 2Schematic diagram of the cross-sectional structure taken along the cutting line AA in FIG. In order to achieve at least one of the above advantages or other advantages, the first embodiment of the present invention provides a light emitting diode. As shown in the figure, the light emitting diode includes a semiconductor stack 12, a first connecting electrode 21, a second connecting electrode 22, a first electrode 31, a second electrode 32, an insulating layer 40, a first pad 41 and a second pad 42.

[0037] The semiconductor stack 12 is disposed on a substrate 10. The substrate 10 may be a transparent substrate 10 or a semi-transparent substrate 10, wherein the transparent substrate 10 or the semi-transparent substrate 10 may allow the light radiated by the light emitting layer 122 to pass through the substrate 10 to reach the side of the substrate 10 away from the semiconductor stack 12. For example, the substrate 10 may be any one of a sapphire flat substrate 10, a sapphire patterned substrate 10, a silicon substrate 10, a silicon carbide substrate 10, a gallium nitride substrate 10, and a glass substrate 10. In some embodiments, the substrate 10 may be thinned or removed to form a thin film chip.

[0038] The semiconductor stack 12 includes a first semiconductor layer 121 , a light emitting layer 122 , and a second semiconductor layer 123 sequentially stacked on the substrate 10 .

[0039] The first semiconductor layer 121 may be an N-type semiconductor layer, which may provide electrons to the light-emitting layer 122 under the action of a power source. In some embodiments, the first semiconductor layer 121 includes an N-type doped nitride layer. The N-type doped nitride layer may include N-type impurities. The N-type impurities may include one of Si, Ge, Sn, or a combination thereof. In some embodiments, the first semiconductor layer 121 is doped with Al to facilitate the light-emitting diode to emit ultraviolet light.

[0040] The light-emitting layer 122 may be a quantum well structure (Quantum Well, referred to as QW). In some embodiments, the light-emitting layer 122 may also be a multiple quantum well structure (Multiple Quantum Well, referred to as MQW), wherein the multiple quantum well structure includes multiple quantum well layers (Well) and multiple quantum barrier layers (Barrier) alternately arranged in a repeated manner, for example, it may be a multiple quantum well structure of GaN / AlGaN, InAlGaN / InAlGaN or InGaN / AlGaN. In addition, the composition and thickness of the well layer in the light-emitting layer 122 determine the wavelength of the generated light. In order to improve the luminous efficiency of the light-emitting layer 122, it can be achieved by changing the depth of the quantum well, the number of layers, thickness and / or other characteristics of the paired quantum wells and quantum barriers in the light-emitting layer 122. In some embodiments, the light-emitting diode is an ultraviolet light-emitting diode, and the light-emitting layer 122 radiates ultraviolet light.

[0041] The second semiconductor layer 123 may be a P-type semiconductor layer, which may provide holes to the light-emitting layer 122 under the action of a power source. In some embodiments, the second semiconductor layer 123 includes a P-type doped nitride layer. The P-type doped nitride layer may include one or more P-type impurities. The P-type impurities may include one or a combination of Mg, Zn, and Be. The second semiconductor layer 123 may be a single-layer structure or a multi-layer structure, and the multi-layer structure has different compositions. In addition, the arrangement of the semiconductor stack 12 is not limited thereto, and other types of semiconductor stacks 12 may be selected according to actual needs. In some embodiments, in order to improve the luminous efficiency, the epitaxial light absorption may be reduced by appropriately thinning the second semiconductor layer 123, and the thickness of the second semiconductor layer 123 may range from 1 to 100 nm, preferably from 5 to 50 nm, and more preferably from 5 to 10 nm.

[0042] The first connection electrode 21 is disposed on the semiconductor stack 12 and electrically connected to the first semiconductor layer 121. The first connection electrode 21 may be a single-layer, double-layer or multi-layer structure, for example, a stacked structure of Ti / Al, Ti / Al / Ti / Au, Ti / Al / Ni / Au, V / Al / Pt / Au, etc. In some embodiments, the first connection electrode 21 may be directly formed on the table of the semiconductor stack 12, the first semiconductor layer 121 has a high Al component, and the first connection electrode 21 is deposited on the table and then subjected to high-temperature fusion to form an alloy, thereby forming a good ohmic contact with the first semiconductor layer 121.

[0043] The second connection electrode 22 is disposed on the semiconductor stack 12 and electrically connected to the second semiconductor layer 123. The second connection electrode 22 may be made of a transparent conductive material or a metal material, which may be adaptively selected according to the doping condition of the surface layer (such as the p-type GaN surface layer) of the second semiconductor layer 123. In some embodiments, the second connection electrode 22 is made of a transparent conductive material, and the material may include indium tin oxide (ITO), indium zinc oxide (IZO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide (CTO), antimony tin oxide (ATO), aluminum zinc oxide (AZO), zinc tin oxide (ZTO), gallium doped zinc oxide (GZO), tungsten doped indium oxide (IWO) or zinc oxide (ZnO), but the embodiments of the present disclosure are not limited thereto.

[0044] The first electrode 31 is connected to the first connection electrode 21. In addition to the current expansion function, the first electrode 31 can also protect the first connection electrode 21 below, and play a supporting and padding role. Preferably, the first electrode 31 completely covers the first connection electrode 21 to avoid metal precipitation in the first connection electrode 21, such as avoiding Al metal precipitation. The material of the first electrode 31 can be selected from one or more of Cr, Pt, Au, Ni, Ti, and Al. Preferably, the surface metal of the first electrode 31 is a Ti metal layer or a Cr metal layer, so that a stable adhesion relationship is formed between the first electrode 31 and the adjacent structural layer.

[0045] The second electrode 32 is connected to the second connection electrode 22. The material of the second electrode 32 can be selected from one or more of Cr, Pt, Au, Ni, Ti, and Al. Preferably, the surface metal of the second electrode 32 is a Ti metal layer or a Cr metal layer, so that a stable adhesion relationship is formed between the second electrode 32 and the adjacent structural layer.

[0046] The insulating layer 40 covers the semiconductor stack 12, the first electrode 31 and the second electrode 32. The insulating layer 40 has a first opening 401 and a second opening 402, wherein the first opening 401 exposes the first electrode 31, and the second opening 402 exposes the second electrode 32. The insulating layer 40 has different functions according to the positions involved. For example, when the insulating layer 40 covers the sidewall of the semiconductor stack 12, it can be used to prevent the first semiconductor layer 121 and the second semiconductor layer 123 from being electrically connected due to leakage of conductive materials, thereby reducing the short circuit anomaly of the light-emitting diode, but the embodiments of the present disclosure are not limited thereto. The material of the insulating layer 40 includes a non-conductive material. The non-conductive material is preferably an inorganic material or a dielectric material. The inorganic material may include silica gel. The dielectric material includes an electrically insulating material such as aluminum oxide, silicon nitride, silicon oxide, titanium oxide, or magnesium fluoride. For example, the insulating layer 40 may be silicon dioxide, silicon nitride, titanium oxide, tantalum oxide, niobium oxide, barium titanate, or a combination thereof, wherein the combination may be, for example, a Bragg reflector (DBR) formed by repeatedly stacking two materials with different refractive indices.

[0047] The first pad 41 is disposed on the insulating layer 40 and is electrically connected to the first electrode 31 through the first opening 401 .

[0048] The second pad 42 is disposed on the insulating layer 40 and is electrically connected to the second electrode 32 through the second opening 402. The first pad 41 and the second pad 42 may be metal pads, which may be formed together using the same material in the same process, and thus may have the same layer structure. The first pad 41 and the second pad 42 are disposed on the insulating layer 40 at intervals.

[0049] Looking down from the top of the light emitting diode toward the semiconductor stack 12, as shown in FIG. Figure 2 As shown, the second electrode 32 includes a starting electrode 321 and a plurality of extended electrodes 322. The plurality of extended electrodes 322 are connected to the starting electrode 321 and extend in a direction away from the starting electrode 321. The second opening 402 is disposed at the end 325 of the extended electrode 322. The plurality of extended electrodes 322 are spaced apart from each other, and the plurality of extended electrodes 322 may be disposed in parallel with each other.

[0050] like Figure 1 As shown, in a conventional light-emitting diode, the second opening of the insulating layer is arranged at the connection between the starting electrode and the extended electrode. Since the connection between the starting electrode and the extended electrode is itself a current convergence area, and the second opening of the insulating layer is located there, the current is further confined near the second opening, resulting in a very congested current at the connection between the starting electrode and the extended electrode, and poor light uniformity. To solve this problem, the present invention arranges the second opening 402 at the end 325 of the extended electrode 322, thereby avoiding current congestion at the starting electrode 321 and the extended electrode 322, so that the light-emitting diode emits light more uniformly.

[0051] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack 12, there is a first spacing L1 between the ends 325 of two adjacent extended electrodes 322. The spacing range of the first spacing L1 is not less than 10 μm, preferably not less than 20 μm, for example, it can be 25 μm, 30 μm, 35 μm. This ensures that the end 325 of the extended electrode 322 below the second opening 402 is disconnected, thereby avoiding the current being confined near the second opening 402. Theoretically, the first spacing L1 can be greater than 0 to achieve discontinuity, but due to the limitation of the actual process capability, it cannot be made too small. In addition, if the first spacing L1 is too small, such as less than 5 μm, the area of ​​the first connecting electrode 21 will become smaller, which will increase the voltage.

[0052] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack 12, there is a second spacing L2 between the second connecting electrodes 22 located below the ends 325 of the two adjacent extended electrodes 322. The spacing range of the second spacing L2 is not less than 5μm, preferably not less than 10μm, for example, it can be 15μm, 20μm, 25μm. This further avoids the current confinement near the second opening 402 and current congestion. In theory, the second spacing L2 can be greater than 0 to achieve discontinuity, but due to the limitation of the actual process capability, it cannot be made too small. In addition, if the second spacing L2 is too small, such as less than 5μm, then the area of ​​the first connecting electrode 21 will become smaller, which will cause the voltage to increase. In some embodiments, the first spacing L1 is greater than the second spacing L2.

[0053] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack 12, there is a third spacing L3 between the second semiconductor layers 123 located below the ends 325 of the two adjacent extended electrodes 322. The second spacing L2 is greater than the third spacing L3. In some embodiments, in order to improve the luminous efficiency, the second semiconductor layer 123 will be appropriately thinned to reduce light absorption, but the lateral current expansion capacity between the semiconductor stacks 12 will be reduced. The reduction in lateral expansion capacity and the high Al component of the deep ultraviolet LED will cause the contact voltage on the N side to increase. Therefore, the N-side electrode (first electrode 31) can be designed to form a ring electrode 311 around the periphery, and a strip electrode 312 is added inside the light-emitting area to connect to reduce the voltage. Specifically, looking down from the top of the light-emitting diode toward the semiconductor stack 12, the first electrode 31 includes a ring electrode 311 and a strip electrode 312, the ring electrode 311 is arranged around the second electrode 32, the strip electrode 312 is connected to the ring electrode 311, and extends toward the starting electrode 321, the strip electrode 312 is located between two adjacent extension electrodes 322, and at least part of the first opening 401 is arranged at the end 325 of the strip electrode 312. By arranging the first opening 401 near the end 325 of the strip electrode 312, current congestion can also be avoided at the connection between the strip electrode 312 and the ring electrode 311, further improving the light emission uniformity of the light-emitting diode.

[0054] In some embodiments, at least part of the first opening 401 is disposed on the annular electrode 311. The first opening 401 is disposed on the annular electrode 311 and the strip electrode 312 respectively, so as to further improve the light emission uniformity on the side of the first electrode 31. In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack 12, the extension electrode 322 is in the shape of a long strip, and the second electrode 32 is in the shape of an "E".

[0055] See also Figures 4 to 9 , Figures 4 to 9 It is a schematic diagram of the structure of the light emitting diode of the first embodiment at various stages in the manufacturing process.

[0056] First, refer to Figure 4 A semiconductor stack 12 including a first semiconductor layer 121, a light emitting layer 122 and a second semiconductor layer 123 is formed on the substrate 10. Then, the second semiconductor layer 123 is etched toward the first semiconductor layer 121 until the first semiconductor layer 121 is exposed.

[0057] Secondly, refer to Figure 5 , a first connection electrode 21 is formed on the first semiconductor layer 121 .

[0058] Next, refer to Figure 6 , a second connection electrode 22 is formed on the second semiconductor layer 123 .

[0059] Follow-up, see Figure 7 A first electrode 31 covering the first connection electrode 21 is disposed at the first connection electrode 21 , and a second electrode 32 is disposed on the second connection electrode 22 .

[0060] Again, refer to Figure 8 , an insulating layer 40 is formed on the semiconductor stack 12, the first electrode 31 and the second electrode 32. The insulating layer 40 is provided with a first opening 401 and a second opening 402, and the first opening 401 and the second opening 402 are respectively used to expose the first electrode 31 and the second electrode 32, so as to facilitate the electrical setting of the subsequent pads. The insulating layer 40 mainly plays the role of electrical isolation and protection of internal components.

[0061] Finally, refer to Fig. 9 A first pad 41 and a second pad 42 are formed on the insulating layer 40 . The first pad 41 is electrically connected to the first electrode 31 through the first opening 401 , and the second pad 42 is electrically connected to the second electrode 32 through the second opening 402 .

[0062] Embodiment 2 See also Fig.10 , Fig.10 : is a schematic diagram of the top view structure of the light emitting diode provided by the second embodiment of the present invention. The same parts of the light emitting diodes of the second embodiment and the first embodiment are not described in detail. Compared with the light emitting diodes of the first embodiment, the light emitting diodes provided by this embodiment are mainly different in that: looking down from the top of the light emitting diode toward the semiconductor stack 12, each extended electrode 322 has a first end 323 and a second end 324 (the first end 323 can be understood as the right end in the figure, and the second end 324 can be understood as the left end in the figure), and the extended electrode 322 extends from the first end 323 to the second end 324. The first ends 323 of the plurality of extended electrodes 322 are connected to each other, and the second ends 324 of the plurality of extended electrodes 322 are not connected, that is, there is a fourth spacing L4 between the second ends 324 of the plurality of extended electrodes 322. Optionally, the spacing range of the fourth spacing L4 is not less than 10μm, preferably not less than 20μm, for example, it can be 25μm, 30μm, 35μm. Theoretically, the fourth spacing L4 can be discontinuous if it is greater than 0, but it cannot be made too small due to the limitation of actual process capability. In addition, if the fourth spacing L4 is too small, such as less than 5 μm, the area of ​​the first connection electrode 21 will become smaller, which will increase the voltage.

[0063] The second opening 402 does not overlap with the first end 323. By setting the second opening 402 at the non-connected end of the extended electrode 322, current congestion is avoided at the first end 323, so that the light emitting diode emits light more uniformly. Preferably, when looking down from the top of the light emitting diode toward the semiconductor stack 12, the minimum spacing between the second opening 402 and the first end 323 is not less than one-fifth of the extension length of the extended electrode 322. In some embodiments, the first end 323 extends laterally from the right boundary of the extended electrode 322 to the left, and the lateral length S2 of the extension does not exceed one-fifth of the lateral length S3 of the extended electrode 322 itself. The second end 324 extends laterally from the left boundary of the extended electrode 322 to the right, and the lateral length S1 of the extension does not exceed one-fifth of the lateral length S3 of the extended electrode 322. In some embodiments, the second opening 402 is set at the second end 324 of the extended electrode 322. However, the present case is not limited to this, and the second opening 402 can also be set near the second end 324, or between the first end 323 and the second segment, etc.

[0064] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack 12, there is a second spacing L2 between the second connecting electrodes 22 located below the second ends 324 of the two adjacent extended electrodes 322. The spacing range of the second spacing L2 is not less than 5μm, preferably not less than 10μm, for example, it can be 15μm, 20μm, 25μm. In theory, the second spacing L2 can be discontinuous if it is greater than 0, but due to the limitation of the actual process capability, it cannot be made too small. In addition, if the second spacing L2 is too small, such as less than 5μm, then the area of ​​the first connecting electrode 21 will become smaller, which will increase the voltage. In some embodiments, the first spacing L1 is greater than the second spacing L2.

[0065] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack 12 , there is a third distance L3 between the second semiconductor layers 123 located below the second ends 324 of two adjacent extension electrodes 322 .

[0066] In some embodiments, in order to improve the light-emitting efficiency, the second semiconductor layer 123 will be appropriately thinned to reduce light absorption, but the lateral current expansion capability between the semiconductor stack 12 will be reduced. The reduction in lateral expansion capability and the high Al component of the deep ultraviolet LED will cause the contact voltage on the N side to increase, so the N-side electrode (first electrode 31) can be designed to form a ring electrode 311 around the periphery, and a strip electrode 312 is added inside the light-emitting area to connect, so as to reduce the voltage. Looking down from the top of the light-emitting diode toward the semiconductor stack 12, the first electrode 31 includes a ring electrode 311 and a strip electrode 312, the ring electrode 311 is arranged around the second electrode 32, the strip electrode 312 is connected to the ring electrode 311, and extends toward the first end 323 of the extension electrode 322, the strip electrode 312 is located between two adjacent extension electrodes 322, and at least part of the first opening 401 overlaps with the end 325 of the strip electrode 312.

[0067] Embodiment 3 In some embodiments, Fig.11 As shown, when looking down from the top of the light emitting diode toward the semiconductor stack 12, the end 325 of the extended electrode 322 has a raised area 50, and the raised area 50 is raised toward the extended electrode 322 adjacent to the extended electrode 322 where the raised area 50 is located. Figure 1 The light-emitting diode shown in the figure has an inward design at the end of the extended electrode due to current congestion and expansion current considerations. In this embodiment, due to the provision of the raised area 50, the area of ​​the second connecting electrode 22 is increased. Looking down from the top of the light-emitting diode toward the semiconductor stack 12, the contact area between the second connecting electrode 22 and the second semiconductor layer 123 accounts for at least 40% of the area of ​​the light-emitting diode. Optionally, the contact area between the second connecting electrode 22 and the second semiconductor layer 123 accounts for 40% to 70% of the area of ​​the light-emitting diode, preferably 45% to 65%. By increasing the area of ​​the second connecting electrode 22, on the one hand, the lateral current expansion capability can be increased and the voltage can be reduced; on the other hand, the current density can be reduced and the aging stability can be improved.

[0068] Due to the setting of the raised area 50, when looking down from the top of the light-emitting diode toward the semiconductor stack 12, the area of ​​the second semiconductor layer 123 accounts for at least 50% of the area of ​​the light-emitting diode. Optionally, the area of ​​the second semiconductor layer 123 accounts for 50-75% of the area of ​​the light-emitting diode, preferably 55-70%. By increasing the area of ​​the second semiconductor layer 123, on the one hand, the light brightness can be improved, and on the other hand, it is beneficial to increase the contact area of ​​the second connecting electrode 22 and improve performance. In some embodiments, considering that in order to improve the luminous efficiency, the second semiconductor layer 123 will be appropriately thinned to reduce light absorption, but the lateral current expansion capacity between the semiconductor stack 12 will be reduced, so that the voltage is not easy to be lowered. Through the design of the present invention, the area of ​​the second semiconductor layer 123 can be increased, so as to achieve the lateral current expansion capacity while thinning the second semiconductor layer 123 and avoid voltage increase.

[0069] In some embodiments, the strip electrode 312 is spaced apart from the ring electrode 311. At least part of the first opening 401 is disposed at one end of the strip electrode 312 close to the starting electrode 321. In some embodiments, at least part of the first opening 401 is disposed at a position of the strip electrode 312 close to the first end 323 of the extension electrode 322. In some embodiments, the strip electrode 312 at the first opening 401 is widened to improve the current expansion performance.

[0070] Embodiment 4 In some embodiments, Fig.12 As shown, compared to Fig.11 The light emitting diode of this embodiment is different mainly in that: when looking down from the top of the light emitting diode toward the semiconductor stack 12, the second semiconductor layer 123 located below the ends 325 of two adjacent extended electrodes 322 are connected to each other. With this design, more area of ​​the second semiconductor layer 123 can be reserved, so that the lateral current expansion capability is guaranteed while the second semiconductor layer 123 is thinned, and the voltage rise is avoided.

[0071] In some embodiments, Fig.13 As shown, compared to Fig.11As for the light-emitting diode of the embodiment, the main difference of the light-emitting diode of the present embodiment is that the light-emitting diode further includes a groove 60, which is formed on the inner and outer side walls of the first semiconductor layer 121. The groove 60 extends from the first semiconductor layer 121 to the substrate 10, and can extend downward from the upper surface of the first semiconductor layer 121 for an appropriate distance without penetrating the upper surface of the substrate 10. The groove 60 can also extend downward from the first semiconductor layer 121 to the upper surface of the substrate 10, that is, the groove 60 completely penetrates the first semiconductor layer 121. The first connecting electrode 21 covers part of the sidewall and bottom of the groove 60, and covers part of the planar area of ​​the first semiconductor layer 121 (such as the upper surface of the first semiconductor layer 121), and forms an ohmic contact with the first semiconductor layer 121. By setting the first connecting electrode 21 to cover the sidewall of the groove 60, the effect of current shunting and lateral injection into the first semiconductor layer 121 can be achieved, the lateral propagation of current in the first semiconductor layer 121 is enhanced, and the operating voltage is reduced.

[0072] In addition, due to the existence of the waveguide effect, the light of the existing light-emitting diode will form an oscillating reflection between the light-emitting layer 122 and the substrate 10, so that the light is absorbed in the semiconductor layer. The present invention uses the setting of the first connecting electrode 21 deep into the groove 60 to block the waveguide effect at the groove 60, so that the first contact electrode 151 can reflect more light emitted by the light-emitting layer 122, and reflect more light to the outside, thereby improving the light extraction efficiency of the light-emitting diode. In some embodiments, the side wall at the groove 60 is inclined, preferably, the inclination angle is less than or equal to 60°, and more preferably, the inclination angle ranges from 25-40°. The side wall of the groove 60 can also be inclined in the form of a step-like shape, which can further increase the contact area between the first connecting electrode 21 and the side wall of the groove 60, and improve the effect of current diversion and lateral injection into the first semiconductor layer 121. However, this patent is not limited to this, and can also be selected and set according to actual conditions. In addition, in the case of Figure 2 , Fig.10 , Fig.11 , Fig.12 In the embodiments of the drawings of FIG. 1 and FIG. 2 , corresponding grooves 60 may also be provided to enhance the lateral propagation of current in the first semiconductor layer 121 and reduce the operating voltage.

[0073] The present invention further provides a light emitting device, which includes a light emitting diode. The light emitting diode adopts the light emitting diode provided by any of the above embodiments, and its specific structure and technical effects are not described in detail.

[0074] In summary, an embodiment of the present invention provides a light-emitting diode and a light-emitting device, which avoids current congestion at the connection between the starting electrode and the extended electrode by setting the second opening 402 near the end 325 of the extended electrode 322, so that the light-emitting diode emits light more evenly and improves the light-emitting characteristics of the light-emitting diode.

[0075] In addition, those skilled in the art should understand that, although there are many problems in the prior art, each embodiment or technical solution of the present invention can be improved in only one or several aspects, without having to solve all the technical problems listed in the prior art or background technology at the same time. Those skilled in the art should understand that the content not mentioned in a claim should not be used as a limitation on the claim.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A light emitting diode, characterized in that: The light emitting diode comprises: A semiconductor stack, comprising a first semiconductor layer, a light emitting layer, and a second semiconductor layer stacked in sequence; A first connecting electrode, disposed on the semiconductor stack and electrically connected to the first semiconductor layer; A second connecting electrode, disposed on the semiconductor stack and electrically connected to the second semiconductor layer; a first electrode connected to the first connection electrode; a second electrode connected to the second connection electrode; An insulating layer covering the semiconductor stack, the first electrode and the second electrode, the insulating layer having a first opening and a second opening; a first pad, disposed on the insulating layer and electrically connected to the first electrode through the first opening; a second pad, disposed on the insulating layer and electrically connected to the second electrode through the second opening; Among them, looking down from the top of the light-emitting diode toward the semiconductor stack, the second electrode includes a starting electrode and a plurality of extended electrodes, the extended electrodes are connected to the starting electrode and extend in a direction away from the starting electrode, and the second opening is arranged at the end of the extended electrode.

2. The light emitting diode according to claim 1, characterized in that: Looking down from the top of the light emitting diode toward the semiconductor stack, there is a first distance between the ends of two adjacent extension electrodes.

3. The light emitting diode according to claim 1, characterized in that: Looking down from the top of the light emitting diode toward the semiconductor stack, there is a second interval between the second connecting electrodes located below the ends of two adjacent extending electrodes.

4. The light emitting diode according to claim 3, characterized in that: Looking down from the top of the light emitting diode toward the semiconductor stack, there is a third distance between the second semiconductor layers located below two adjacent ends of the extended electrodes.

5. The light emitting diode according to claim 3, characterized in that: Looking down toward the semiconductor stack from above the light emitting diode, the second semiconductor layers located below the ends of two adjacent extended electrodes are connected to each other.

6. The light emitting diode according to claim 1, characterized in that: Looking down from above the light-emitting diode toward the semiconductor stack, the end of the extension electrode has a protruding region, and the protruding region protrudes toward the extension electrode adjacent to the extension electrode where the protruding region is located.

7. The light emitting diode according to claim 1, characterized in that: Looking down toward the semiconductor stack from above the light-emitting diode, the first electrode includes a ring electrode and a strip electrode, the ring electrode is arranged around the second electrode, the strip electrode is connected to the ring electrode and extends toward the starting electrode, the strip electrode is located between two adjacent extended electrodes, and at least part of the first opening is arranged at the end of the strip electrode.

8. The light emitting diode according to claim 1, characterized in that: Looking down toward the semiconductor stack from above the light-emitting diode, the first electrode includes a ring electrode and a strip electrode, the ring electrode is arranged around the second electrode, the strip electrode is located between two adjacent extended electrodes, the strip electrode and the ring electrode are spaced apart, and at least part of the first opening is arranged at one end of the strip electrode close to the starting electrode.

9. The light emitting diode according to claim 7 or 8, characterized in that: At least part of the first opening is disposed on the annular electrode.

10. A light emitting diode, characterized in that: The light emitting diode comprises: A semiconductor stack, comprising a first semiconductor layer, a light emitting layer, and a second semiconductor layer stacked in sequence; A first connecting electrode, disposed on the semiconductor stack and electrically connected to the first semiconductor layer; A second connecting electrode, disposed on the semiconductor stack and electrically connected to the second semiconductor layer; a first electrode connected to the first connection electrode; a second electrode connected to the second connection electrode; An insulating layer covering the semiconductor stack, the first electrode and the second electrode, the insulating layer having a first opening and a second opening; a first pad, disposed on the insulating layer and electrically connected to the first electrode through the first opening; a second pad, disposed on the insulating layer and electrically connected to the second electrode through the second opening; Among them, looking down toward the semiconductor stack from above the light-emitting diode, the second electrode includes a plurality of extended electrodes, the extended electrode has a first end and a second end, the extended electrode extends from the first end to the second end, the first ends of the plurality of extended electrodes are connected to each other, there is a fourth spacing between the second ends of the plurality of extended electrodes, and the second opening does not overlap with the first end.

11. The light emitting diode according to claim 10, characterized in that: The second opening is disposed at the second end of the extension electrode.

12. The light emitting diode according to claim 10, characterized in that: Looking down from the top of the light emitting diode toward the semiconductor stack, there is a second interval between the second connecting electrodes located below the second ends of two adjacent extending electrodes.

13. The light emitting diode according to claim 12, characterized in that: Looking down from the top of the light emitting diode toward the semiconductor stack, there is a third distance between the second semiconductor layers located below the second ends of two adjacent extended electrodes.

14. The light emitting diode according to claim 10, characterized in that: Looking down toward the semiconductor stack from above the light-emitting diode, the first electrode includes a ring electrode and a strip electrode, the ring electrode is arranged around the second electrode, the strip electrode is connected to the ring electrode and extends toward the first end of the extended electrode, the strip electrode is located between two adjacent extended electrodes, and at least part of the first opening overlaps with the end of the strip electrode.

15. The light emitting diode according to claim 10, characterized in that: Looking down toward the semiconductor stack from above the light-emitting diode, the first electrode includes a ring electrode and a strip electrode, the ring electrode is arranged around the second electrode, the strip electrode is located between two adjacent extended electrodes, the strip electrode and the ring electrode are spaced apart, and at least part of the first opening is arranged at a position of the strip electrode close to the first end of the extended electrode.

16. The light emitting diode according to claim 1 or 10, characterized in that: The thickness of the second semiconductor layer is in the range of 1-100 nm.

17. The light emitting diode according to claim 1, characterized in that: Looking down toward the semiconductor stack from above the light-emitting diode, the contact area between the second connecting electrode and the second semiconductor layer accounts for at least 40% of the area of ​​the light-emitting diode.

18. The light emitting diode according to claim 1, characterized in that: Looking down toward the semiconductor stack from above the light-emitting diode, the area of ​​the second semiconductor layer accounts for at least 50% of the area of ​​the light-emitting diode.

19. The light emitting diode according to claim 1 or 10, characterized in that: The light emitting diode is an ultraviolet light emitting diode.

20. A light emitting device, characterized in that: The light emitting device comprises a light emitting diode, and the light emitting diode is a light emitting diode as claimed in any one of claims 1 to 19.

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