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 laminated 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, the first connecting electrode and the second connecting electrode are connected with the semiconductor laminated layer, the first electrode is connected with the first connecting electrode, and the second electrode is connected with the second connecting electrode. 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, the second bonding pad is connected with the second electrode, the first electrode comprises annular electrodes and strip-shaped electrodes, the strip-shaped electrodes and the annular electrodes are arranged at intervals, the second electrode comprises extension electrodes, and the strip-shaped electrodes are located between the extension electrodes. The second opening is formed in one side of the second electrode, and the first opening is formed in one end, away from the second opening, of the strip-shaped electrode. Therefore, current congestion of the light-emitting diode can be avoided, the light-emitting uniformity of the light-emitting diode is improved, and the light-emitting quality 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. With the development of technology, 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. Among them, looking down from the top of the light-emitting diode toward the semiconductor stack, the first electrode includes a ring electrode and at least one strip electrode, the strip electrode and the ring electrode are arranged at intervals, the second electrode includes at least two extended electrodes, the ring electrode is arranged around the second electrode, the strip electrode is located between two adjacent extended electrodes, the second opening is arranged on one side of the second electrode, the end of the strip electrode close to the second opening is defined as the first end, the end of the strip electrode away from the second opening is defined as the second end, and at least part of the first opening is arranged at the second end of the strip electrode.

[0006] 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.

[0007] An embodiment of the present invention provides a light-emitting diode and a light-emitting device. In this way, a strip electrode and a ring electrode are spaced apart, and a first opening is disposed at an end of the strip electrode away from a second opening. On the one hand, the first opening is disposed at a position spaced apart from the strip electrode and the ring electrode, and on the other hand, the first opening and the second opening are distributed on different sides, thereby avoiding current congestion, making the light-emitting diode emit light more uniformly, and improving the light-emitting characteristics of the light-emitting diode.

[0008] 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

[0009] 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.

[0010] Figure 1It 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 2 A 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 It is a schematic diagram of a top view of the structure of a light emitting diode provided in a fourth embodiment of the present invention.

[0011] 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; 313-first end; 314-second end; 32-second electrode; 322-extended electrode; 323-first side; 324-second side; 40-insulating layer; 401-first opening; 402-second opening; 41-first solder pad; 42-second solder pad; 50-raised area; 51-raised structure; 60-groove; 61-first side; 62-second side; 63-third side; 64-fourth side; L1-first spacing; L2-second spacing; L3-third spacing; S1-first minimum spacing; S2-second minimum spacing; S3-horizontal minimum spacing; S4-extended length. DETAILED DESCRIPTION

[0012] 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.

[0013] 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".

[0014] 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. Among them, looking down from the top of the light-emitting diode toward the semiconductor stack, the first electrode includes a ring electrode and at least one strip electrode, the strip electrode and the ring electrode are arranged at intervals, the second electrode includes at least two extended electrodes, the ring electrode is arranged around the second electrode, the strip electrode is located between two adjacent extended electrodes, the second opening is arranged on one side of the second electrode, the end of the strip electrode close to the second opening is defined as the first end, the end of the strip electrode away from the second opening is defined as the second end, and at least part of the first opening is arranged at the second end of the strip electrode. The present invention arranges the strip electrode and the ring electrode at intervals, and the first opening is arranged at the end of the strip electrode away from the second opening. On the one hand, the first opening is arranged at the position where the strip electrode and the ring electrode are spaced apart, and on the other hand, the first opening and the second opening are distributed on different sides, thereby avoiding current congestion and improving the light emission uniformity of the light-emitting diode.

[0015] In some embodiments, the number of strip electrodes is a, and the number of extended electrodes is b, where b=a+1, so that each strip electrode can be sandwiched between two extended electrodes, which is conducive to more uniform current distribution.

[0016] In some embodiments, two sides of two adjacent extended electrodes are connected to each other to form a closed loop pattern. Through the above design, the annular electrode surrounds the second electrode and the second electrode surrounds the strip electrode, so that the spacing between various positions of the first electrode and various positions of the second electrode is more uniform, which is conducive to more uniform current distribution, making the light emitting diode emit light more uniformly, and further improving the light emitting characteristics of the light emitting diode.

[0017] In some embodiments, the number of closed loop patterns is 2, and when looking down from the top of the light-emitting diode toward the semiconductor stack, the two closed loop patterns are connected up and down to form a "sun" shape. Through the above design, the annular electrode surrounds the second electrode and the second electrode surrounds the strip electrode, so that the spacing from various positions of the first electrode to various positions of the second electrode is more uniform, which is conducive to more uniform current distribution, making the light-emitting diode emit light more uniformly, and can further improve the light-emitting characteristics of the light-emitting diode.

[0018] In some embodiments, the extended electrode has a first side away from the second opening and a second side close to the second opening, the first sides of two adjacent extended electrodes are connected to each other, and a first spacing is provided between the second sides of two adjacent extended electrodes. By spacing the second sides of two adjacent extended electrodes and arranging the second opening at this position, it is also possible to avoid arranging the second opening in the current convergence area, further avoiding current confinement near the second opening, resulting in current congestion and poor light uniformity.

[0019] 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 sides of two adjacent extended electrodes, thereby ensuring that the electrode below the second opening is disconnected, further avoiding current congestion caused by current confinement near the second opening.

[0020] 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 sides of two adjacent extended electrodes, so that the second semiconductor layers at the ends of the extended electrodes are disconnected to enhance the current spreading performance.

[0021] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack, the first opening and the second opening have a minimum horizontal spacing, and the minimum horizontal spacing is not less than one-fourth of the extension length of the extension electrode. Ensuring that the first opening and the second opening have a certain spacing can improve the overall current uniformity of the light-emitting diode and avoid current congestion.

[0022] In some embodiments, the strip electrode has a protruding structure at the second end, and at least part of the first opening is disposed on the protruding structure. By designing the protruding structure and disposing the first opening at the protruding position, sufficient current conduction channels are ensured to avoid current congestion at the first opening.

[0023] In some embodiments, at least part of the first opening is disposed on the annular electrode. By disposing the first openings on the strip electrode and the annular electrode respectively, the light uniformity on the first electrode side is further improved, thereby improving the light emitting characteristics of the light emitting diode.

[0024] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack, the light-emitting diode has a first side, a second side, a third side, and a fourth side connected in sequence, the first side and the third side are arranged opposite to each other, the second side and the fourth side are arranged opposite to each other, the second opening is closer to the fourth side than the first opening, and the first opening is closer to the second side than the second opening. The first opening and the second opening are respectively distributed on opposite sides close to the light-emitting diode, thereby avoiding current congestion.

[0025] 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.

[0026] 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 45% 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.

[0027] In some embodiments, when looking down at the semiconductor stack from above the light-emitting diode, the area of ​​the second semiconductor layer accounts for at least 55% of the area of ​​the light-emitting diode. By increasing the area of ​​the second semiconductor layer, the light brightness can be improved on the one hand, and the contact area of ​​the second connection electrode can be increased on the other hand, thereby improving performance.

[0028] Through the design of the present invention, more area of ​​the second semiconductor layer can be reserved, so as to achieve the goal of ensuring the lateral current expansion capability and avoiding voltage increase while thinning the second semiconductor layer.

[0029] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack, the area ratio of the first connection electrode to the second connection electrode is no greater than 1:4. The design of the present invention can increase the area of ​​the second connection electrode, which can increase the lateral current expansion capability and reduce the voltage on the one hand, and reduce the current density and improve the aging stability on the other hand.

[0030] In some embodiments, the light emitting diode is an ultraviolet light emitting diode.

[0031] 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.

[0032] 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 2 Schematic 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.

[0033] The semiconductor stack 12 is disposed on a substrate 10. The substrate 10 may be a transparent substrate or a semi-transparent substrate, wherein the transparent substrate or the semi-transparent substrate 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, a sapphire patterned substrate, a silicon substrate, a silicon carbide substrate, a gallium nitride substrate, and a glass substrate. In some embodiments, the substrate 10 may be thinned or removed to form a thin film chip.

[0034] 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 .

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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 .

[0044] 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.

[0045] Looking down from the top of the light emitting diode toward the semiconductor stack 1212, as shown in FIG. Figure 2 As shown, the first electrode 31 includes a ring electrode 311 and at least one strip electrode 312. The number of strip electrodes 312 in the illustrated embodiment is 2. The strip electrode 312 and the ring electrode 311 are arranged at intervals, that is, the two do not overlap when viewed from above. 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. 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 3131) can be designed to surround the periphery to form a ring electrode 311, and a strip electrode 312 is added inside the light-emitting area to reduce the voltage.

[0046] The second electrode 32 includes at least two extension electrodes 322. In the illustrated embodiment, the number of the extension electrodes 322 is 3. The annular electrode 311 is disposed around the second electrode 32, and the plurality of extension electrodes 322 are located inside the annular electrode 311. The strip electrode 312 is located between two adjacent extension electrodes 322. For example, a strip electrode 312 is disposed between the upper and lower extension electrodes 322. The second opening 402 is disposed on one side of the second electrode 32. In some embodiments, the number of the second openings 402 is multiple, and each extension electrode 322 is provided with a second opening 402. The end of the strip electrode 312 close to the second opening 402 is defined as the first end 313, and the end of the strip electrode 312 away from the second opening 402 is defined as the second end 314. For example, the first end 313 is the left end of the strip electrode 312, and the second end 314 is the right end of the strip electrode 312. At least part of the first opening 401 is disposed at the second end 314 of the strip electrode 312. This avoids current congestion, makes the light emitting diode emit light more evenly, and improves the light emitting characteristics of the light emitting diode.

[0047] like Figure 1 As shown, in a conventional light-emitting diode, the strip electrode is connected to the annular electrode and extends from the annular electrode to the inside thereof, and the first opening of the insulating layer is arranged at the connection between the strip electrode and the annular electrode. Since the connection itself is a current convergence area, and the opening of the insulating layer is located there, the current is further confined near the first opening, resulting in current congestion and poor light uniformity. In order to solve this problem, the present invention separates the strip electrode 312 from the annular electrode 311, and at the same time sets the first opening 401 at one end of the strip electrode 312 away from the second opening 402. On the one hand, the first opening 401 is set at the position where the strip electrode 312 is separated from the annular electrode 311, and on the other hand, the first opening 401 and the second opening 402 are distributed on different sides, thereby avoiding current congestion and making the light-emitting diode emit more uniform light. In some embodiments, the number of strip electrodes 312 is a, and the number of extended electrodes 322 is b, b=a+1. That is, the number of the extended electrodes 322 is one more than the number of the strip electrodes 312 , so that each strip electrode 312 can be sandwiched between two extended electrodes 322 .

[0048] In some embodiments, Figure 2As shown, looking down from the top of the light-emitting diode toward the semiconductor stack 12, the two sides of the two adjacent extended electrodes 322 are connected to each other to form a closed loop pattern. Specifically, the number of closed loop patterns is 2, and the two closed loop patterns are connected up and down to form a "sun" shape. Through the above design, the annular electrode 311 surrounds the second electrode 32 and the second electrode 32 surrounds the strip electrode 312, so that the spacing from various positions of the first electrode 31 to various positions of the second electrode 32 is more uniform, which is conducive to more uniform current distribution, so that the light-emitting diode emits light more evenly, and the light-emitting characteristics of the light-emitting diode can be further improved.

[0049] Looking down from the top of the light-emitting diode toward the semiconductor stack 12, the area ratio of the first connection electrode 21 to the second connection electrode 22 is not greater than 1:4. Increasing the area of ​​the second connection electrode 22 can increase the lateral current expansion capability and reduce the voltage; on the other hand, it can also reduce the current density and improve the aging stability.

[0050] In some embodiments, looking down from the top of the light-emitting diode toward the semiconductor stack 12, the first opening 401 and the second opening 402 have a minimum horizontal spacing S3, and the minimum horizontal spacing S3 is not less than one-fourth of the extension length S4 of the extension electrode 322. In some embodiments, the minimum horizontal spacing S3 between the first opening 401 and the second opening 402 is not less than 70 μm, preferably 90 to 130 μm, for example, it can be 100 μm, 110 μm, 120 μm. As shown in the figure, the minimum horizontal spacing S3 refers to the minimum spacing between the first opening 401 and the second opening 402 in a horizontal direction, rather than the minimum oblique spacing between the two. Ensuring that the first opening 401 and the second opening 402 have a certain spacing S3 improves the overall current uniformity of the light-emitting diode and avoids current congestion.

[0051] In some embodiments, the strip electrode 312 has a protruding structure 51 at the second end 314, and at least part of the first opening 401 is disposed at the protruding structure 51. The first opening 401 is disposed at the protruding structure 51 to ensure that there is a sufficient current conduction channel at the first opening 401 to increase current conduction and avoid current congestion at the first opening 401.

[0052] In some embodiments, at least part of the first opening 401 is disposed on the annular electrode 311. Disposing the first opening 401 on the annular electrode 311 and the strip electrode 312 respectively can further improve the light emission uniformity on the first electrode 31 side. Figure 2As shown, looking down from the top of the light-emitting diode toward the semiconductor stack 12, the light-emitting diode has a first side 61, a second side 62, a third side 63 and a fourth side 64 connected in sequence. In this embodiment, the first side 61, the second side 62, the third side 63 and the fourth side 64 are respectively the top, the right, the bottom and the left. The first side 61 and the third side 63 are arranged oppositely, the second side 62 and the fourth side 64 are arranged oppositely, the second opening 402 is closer to the fourth side 64 than the first opening 401, and the first opening 401 is closer to the second side 62 than the second opening 402. In other words, the first opening 401 and the second opening 402 are respectively arranged on opposite sides close to the light-emitting diode, so as to avoid current congestion and improve the light uniformity of the light-emitting diode.

[0053] In some embodiments, when looking down from the top of the light-emitting diode toward the semiconductor stack 12, the first minimum spacing S1 from the first opening 401 in the strip electrode 312 to the second side 62 is less than 1 / 2 of the extension length S4 of the extension electrode 322, and greater than 1 / 10 of the extension length S4 of the extension electrode 322. The second minimum spacing S2 from the second opening 402 to the fourth side 64 is less than 1 / 2 of the extension length S4 of the extension electrode 322, and greater than 1 / 15 of the extension length S4 of the extension electrode 322. The first minimum spacing S1 is greater than the second minimum spacing S2.

[0054] 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.

[0055] 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.

[0056] Secondly, refer to Figure 5 , a first connection electrode 21 is formed on the first semiconductor layer 121 .

[0057] Next, refer to Figure 6 , a second connection electrode 22 is formed on the second semiconductor layer 123 .

[0058] 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 .

[0059] 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.

[0060] 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 .

[0061] Embodiment 2 See also Fig.10 , Fig.10 FIG. 1 is a schematic diagram of a top view of a light emitting diode provided in the second embodiment of the present invention. Figure 2 As for the light emitting diode of the first embodiment shown, the same parts will not be described in detail. The difference of this embodiment is mainly that: the extended electrode 322 has a first side 323 away from the second opening 402 and a second side 324 close to the second opening 402, the first side 323 and the second side 324 are arranged opposite to each other, and the second opening 402 is arranged close to the second side 324. Taking the figure as an example, the first side 323 is the right side of the extended electrode 322, and the second side 324 is the left side of the extended electrode 322. The first sides 323 of two adjacent extended electrodes 322 are connected to each other to form an integral electrode, and the second sides 324 of two adjacent extended electrodes 322 have a first spacing L1 between them. The spacing range of the first spacing L1 is not less than 10μm, preferably not less than 20μm, for example, it can be 25μm, 30μm, 35μm. By spacing the second sides 324 of two adjacent extension electrodes 322 and arranging the second opening 402 at this position, it is also possible to avoid arranging the second opening 402 in the current convergence area, further avoiding the current being confined near the second opening 402, resulting in current congestion and poor light uniformity. Theoretically, the first spacing L1 can be discontinuous if it is greater than 0, but it cannot be made too small due to the limitation of the actual process capability. In addition, if the first spacing L1 is too small, such as less than 5μm, the area of ​​the first connection electrode 21 will become smaller, which will increase the voltage.

[0062] 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 side 324 of 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 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 cause the voltage to increase. In some embodiments, the first spacing L1 is greater than the second spacing L2.

[0063] In some embodiments, when looking down from the top of the light emitting diode toward the semiconductor stack 12, the end of the extension electrode 322 has a raised region 50, and the raised region 50 is raised toward the extension electrode 322 adjacent to the extension electrode 322 where the raised region 50 is located. Figure 1 The light-emitting diode shown in the figure has an inward design at the end due to current congestion and expansion current considerations, and the area of ​​the second connecting electrode 22 is increased due to the provision of the raised area 50 in this embodiment. 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 45% 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 45-70% of the area of ​​the light-emitting diode, preferably 45-65%. 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.

[0064] 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 55% of the area of ​​the light-emitting diode. Optionally, the area of ​​the second semiconductor layer 123 accounts for 55-75% 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.

[0065] Embodiment 3 See also Fig.11 , Fig.11 FIG. 1 is a schematic diagram of a top view of a light emitting diode provided in the third embodiment of the present invention. Fig.10 As for the light emitting diode of the second embodiment shown, the difference of this embodiment is mainly that: 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 second sides 324 of the two adjacent extended electrodes 322. In other words, the second semiconductor layers 123 located below the second sides 324 of the two adjacent extended electrodes 322 in the second embodiment are connected to each other, thereby retaining more area of ​​the second semiconductor layer 123, achieving the goal of ensuring the lateral current expansion capability and avoiding voltage increase while thinning the second semiconductor layer 123. Optionally, the second spacing L2 is greater than the third spacing L3.

[0066] In some embodiments, Fig.12 As shown, compared to Fig.11 As 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.

[0067] 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 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.

[0068] 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.

[0069] In summary, an embodiment of the present invention provides a light-emitting diode and a light-emitting device, in which the strip electrode 312 and the ring electrode 311 are spaced apart, and the first opening 401 is arranged on an end of the strip electrode 312 away from the second opening 402, so that the first opening 401 and the second opening 402 are distributed on different sides, thereby avoiding current congestion, making the light-emitting diode emit light more uniformly, and improving the light-emitting characteristics of the light-emitting diode.

[0070] 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.

[0071] 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 by 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 toward the semiconductor stack from above the light-emitting diode, the first electrode includes a ring electrode and at least one strip electrode, the strip electrode and the ring electrode are arranged at intervals, the second electrode includes at least two extended electrodes, the ring electrode is arranged around the second electrode, the strip electrode is located between two adjacent extended electrodes, the second opening is arranged on one side of the second electrode, and the end of the strip electrode close to the second opening is defined as the first end, and the end of the strip electrode away from the second opening is defined as the second end, and at least part of the first opening is arranged at the second end of the strip electrode.

2. The light emitting diode according to claim 1, characterized in that: The number of the strip electrodes is a, and the number of the extended electrodes is b, where b=a+1.

3. The light emitting diode according to claim 1, characterized in that: The two sides of two adjacent extension electrodes are connected to each other to form a closed loop pattern.

4. The light emitting diode according to claim 3, characterized in that: The number of the closed loop patterns is two, and when looking down toward the semiconductor stack from above the light-emitting diode, the two closed loop patterns are connected up and down to form a "sun" shape.

5. The light emitting diode according to claim 1, characterized in that: The extended electrode has a first side away from the second opening and a second side close to the second opening. The first sides of two adjacent extended electrodes are connected to each other, and a first interval exists between the second sides of two adjacent extended electrodes.

6. The light emitting diode according to claim 5, characterized in that: Looking down from above the light emitting diode toward the semiconductor stack, there is a second interval between the second connecting electrodes located below the second sides of two adjacent extending electrodes.

7. The light emitting diode according to claim 5, 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 sides of two adjacent extended electrodes.

8. 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, the first opening and the second opening have a minimum horizontal distance, and the minimum horizontal distance is not less than one quarter of the extension length of the extension electrode.

9. The light emitting diode according to claim 1, characterized in that: The strip electrode has a protruding structure at the second end, and at least part of the first opening is disposed on the protruding structure.

10. The light emitting diode according to claim 1, characterized in that: At least part of the first opening is disposed in the annular electrode.

11. The light emitting diode according to claim 1, characterized in that: Looking down toward the semiconductor stack from above the light-emitting diode, the light-emitting diode has a first side, a second side, a third side and a fourth side connected in sequence, the first side and the third side are arranged opposite to each other, the second side and the fourth side are arranged opposite to each other, the second opening is closer to the fourth side than the first opening, and the first opening is closer to the second side than the second opening.

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

13. 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 45% of the area of ​​the light-emitting diode.

14. 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 55% of the area of ​​the light-emitting diode.

15. 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 ratio of the first connecting electrode to the second connecting electrode is not greater than 1:

4.

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

17. 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 16.

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