Light emitting diode

Abstract

The invention provides a light emitting diode. The light emitting diode comprises a first epitaxial structure, a second epitaxial structure, a first current blocking layer, a second electrode and a connecting electrode, the first epitaxial structure comprises a first step structure, and the first step structure comprises a first step bottom surface and a first step top surface; the second epitaxial structure comprises a second step structure, and the second step structure comprises a second step bottom surface and a second step top surface; a groove is formed between the first epitaxial structure and the second epitaxial structure; the first current blocking layer extends from the first step structure to the second step structure, and the connecting electrode is located on the first current blocking layer and electrically connected with the first epitaxial structure and the second epitaxial structure; and the distance from the edge of the projection of the second electrode on the second epitaxial structure to the edge of the top surface of the second step is 30-45 microns.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of light emitting devices, and in particular to a light emitting diode. BACKGROUND

[0002] Light emitting diode (LED) is a kind of semiconductor device capable of emitting light, which has the advantages of energy saving, high brightness, high durability, long service life and lightness, and has been widely used in the two fields of backlight display and direct display.

[0003] The related technology provides a light emitting diode, and the light emitting diode structure includes an epitaxial structure, a first electrode and a second electrode. The epitaxial structure is in a stepped structure, and the first electrode and the second electrode are connected with the bottom surface and the top surface of the step respectively.

[0004] In the light emitting diode, how to improve the anti-forward electrostatic discharge (ESD) breakdown capability of the light emitting diode is a major focus of current research. SUMMARY

[0005] The embodiment of the present disclosure provides a light emitting diode, which can significantly improve the anti-forward electrostatic discharge breakdown capability of the light emitting diode. The technical scheme is as follows:

[0006] In one aspect, a light emitting diode is provided, which includes:

[0007] a first epitaxial structure, a second epitaxial structure, a first current blocking layer, a second electrode and a connecting electrode;

[0008] The first epitaxial structure includes a first stepped structure, and the first stepped structure includes a first stepped bottom surface and a first stepped top surface. The second epitaxial structure includes a second stepped structure, and the second stepped structure includes a second stepped bottom surface and a second stepped top surface. There is a groove between the first epitaxial structure and the second epitaxial structure. The first current blocking layer extends from the first stepped structure to the second stepped structure, and the connecting electrode is located on the first current blocking layer and is electrically connected with the first epitaxial structure and the second epitaxial structure respectively.

[0009] The distance from the edge of the second electrode projected on the second epitaxial structure to the second stepped top surface edge is 30-45 μm.

[0010] Optionally, the light emitting diode includes two circular second electrodes.

[0011] Optionally, the two circular second electrodes are symmetrical about a straight line parallel to the long side of the light emitting diode.

[0012] Optionally, the light emitting diode comprises two first current blocking layers and two connecting electrodes, and the two first current blocking layers and the two connecting electrodes correspond one by one; the two first current blocking layers are arranged at intervals.

[0013] The connecting electrode is in a strip shape, and the first current blocking layer is in a strip shape.

[0014] The width of the middle part of the connecting electrode is greater than the width of the two sides, and the width of one side of the first current blocking layer is less than the width of the other side.

[0015] Optionally, the light emitting diode further comprises a substrate, and the projection of the first current blocking layer on the substrate is located in a closed first curve after being scaled by 0.8 to 1.2 times in equal proportion, and the first curve comprises 13 line segments Si, 1≤i≤13, which are connected end to end.

[0016] The line segments S1, S3, S6, S8, S10 and S12 are circular arcs, and the line segments S2, S4, S5, S7, S9, S11 and S13 are straight lines.

[0017] The circular arc angles of the line segments S1, S3, S6, S8, S10 and S12 are respectively 180.0±3°, 22.0±3°, 90.0±3°, 90.0±3°, 45.0±3° and 45±3°.

[0018] The rotation directions of the line segments S1, S3, S6, S8, S10 and S12 are respectively counterclockwise, clockwise, counterclockwise, counterclockwise, counterclockwise and clockwise.

[0019] Optionally, the radii of the line segments S1, S3, S6, S8, S10 and S12 are respectively 12.5±2μm, 10.0±2μm, 6.0±2μm, 6.0±2μm, 10.0±2μm and 10.0±2μm.

[0020] Optionally, the lengths of the line segments S2, S4, S5, S7, S9, S11 and S13 are respectively 12.5±2μm, 18.5±2μm, 28.0±2μm, 37.0±2μm, 21.3±2μm, 14.6±2μm and 59±2μm.

[0021] Optionally, the light emitting diode further comprises a substrate, and the projection of the connecting electrode on the substrate is located in a closed second curve after being scaled by 0.8 to 1.2 times in equal proportion, and the second curve comprises 22 line segments Si, 1≤i≤22, which are connected end to end.

[0022] The line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are circular arcs, and the line segments S2, S4, S6, S8, S10, S12, S14, S16, S18, S20 and S22 are straight lines;

[0023] The circular arc angles of the line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are respectively 180.0±3°, 20.0±3°, 20.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 50.0±3° and 50±3°.

[0024] The rotation directions of the line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are respectively counterclockwise, clockwise, counterclockwise, clockwise, counterclockwise, counterclockwise, counterclockwise, counterclockwise, clockwise, counterclockwise and clockwise.

[0025] Optionally, the radii of the line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are respectively 2.5±2μm, 20.0±2μm, 5.0±2μm, 5.0±2μm, 3.0±2μm, 3.0±2μm, 3.0±2μm, 3.0±2μm, 5.0±2μm, 10.0±2μm and 20.0±2μm.

[0026] Optionally, the lengths of the line segments S2, S4, S6, S8, S10, S12, S14, S16, S18, S20 and S22 are respectively 57.4±2μm, 13.0±2μm, 23.0±2μm, 1.0±2μm, 1.0±2μm, 37.0±2μm, 1.0±2μm, 1.0±2μm, 19.0±2μm, 4.0±2μm and 102.0±2μm.

[0027] The technical scheme provided by the embodiments of the present disclosure has the following beneficial effects:

[0028] In the embodiment of the present disclosure, the light emitting diode comprises a first epitaxial structure and a second epitaxial structure, both of which are in a stepped shape, and the second electrode and the connecting electrode realize the series connection between the two epitaxial structures, the epitaxial structure is divided into two parts and then connected through the connecting electrode, the two epitaxial structures divide the current into two paths, the two paths of current are transmitted to the other side epitaxial structure, and the current spreading effect is improved on the other side epitaxial structure, the current aggregation is prevented, and the forward electrostatic discharge breakdown resistance of the light emitting diode is enhanced; the distance from the edge of the second electrode projected on the second epitaxial structure to the edge of the top surface of the second step is 30-45 μm, so that the second electrode is prevented from being too close to the edge of the epitaxial structure, the current distribution in the second epitaxial structure is more uniform, and the current distribution is optimized. Through test verification, the light emitting diode provided in the embodiment of the present disclosure has better forward electrostatic discharge breakdown resistance, and the yield of the light emitting diode is improved. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative labor.

[0030] Figure 1 is a structure schematic diagram of a cross section of a light emitting diode provided by the embodiment of the present disclosure;

[0031] Figure 2 is a structure schematic diagram of a cross section of a light emitting diode provided by the embodiment of the present disclosure;

[0032] Figure 3 is a top view of a light emitting diode provided by the embodiment of the present disclosure;

[0033] Figure 4 is a top view of a light emitting diode provided by the embodiment of the present disclosure;

[0034] Figure 5 is a projection schematic diagram of a first current blocking layer of a light emitting diode provided by the embodiment of the present disclosure on a substrate; Figure 4

[0035] Figure 6 is a projection schematic diagram of a connecting electrode of a light emitting diode provided by the embodiment of the present disclosure on a substrate; Figure 4

[0036] Figure 7 is a flow chart of a light emitting diode preparation method provided by the embodiment of the present disclosure;

[0037] Figure 8 is a flow chart of another light emitting diode preparation method provided by the embodiment of the present disclosure;​​

[0038] Figure 9 is an embodiment of the present disclosure Figure 3 and Figure 4 The current expansion of the light-emitting diode provided is intended.

[0039] The reference signs are as follows:

[0040] 11: first epitaxial structure; 12: second epitaxial structure;

[0041] 100: substrate; 101: first semiconductor layer; 102: active layer; 103: second semiconductor layer; 104: first current blocking layer; 105: second current blocking layer; 106: first transparent conductive layer; 107: second transparent conductive layer; 108: passivation layer;

[0042] 201: first electrode; 202: second electrode; 203: connecting electrode;

[0043] 301: first electrode pad; 302: second electrode pad;

[0044] 1001: first step structure; 1002: second step structure; 1003: groove;

[0045] α: circular arc angle; R: radius; L: length;

[0046] a: distance from the edge of the second electrode projected on the second epitaxial structure to the edge of the top surface of the second step; z: straight line parallel to the long side of the light-emitting diode. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the embodiments of the present disclosure will be described in further detail below with reference to the drawings.

[0048] Figure 1 is a structure schematic diagram of a cross section of a light-emitting diode provided by an embodiment of the present disclosure. Figure 2 is a structure schematic diagram of a cross section of a light-emitting diode provided by an embodiment of the present disclosure. Referring to Figure 1 and Figure 2 The light-emitting diode comprises a first epitaxial structure 11, a second epitaxial structure 12, a first current blocking layer 104, a second electrode 202 and a connecting electrode 203.

[0049] The first epitaxial structure 11 includes a first step structure 1001 including a first step bottom surface and a first step top surface; the second epitaxial structure 12 includes a second step structure 1002 including a second step bottom surface and a second step top surface; the first epitaxial structure 11 and the second epitaxial structure 12 have a groove 1003 therebetween; the first current blocking layer 104 extends from the first step structure 1001 to the second step structure 1002, and the connecting electrode 203 is located on the first current blocking layer 104 and electrically connected to the first epitaxial structure 11 and the second epitaxial structure 12, respectively.

[0050] The distance a from the edge of the second electrode 202 projected on the second epitaxial structure 12 to the edge of the second step top surface is 30-45 μm.

[0051] In the embodiment of the present disclosure, the light-emitting diode includes a first epitaxial structure and a second epitaxial structure, both of which are in a step shape; the second electrode and the connecting electrode realize the series connection between the two epitaxial structures, the epitaxial structure is divided into two parts and then connected through the connecting electrode, the two epitaxial structures divide the current into two paths, the two paths of current are transmitted to the other side epitaxial structure, and the current is expanded on the other side epitaxial structure, thereby improving the current expansion effect, preventing current aggregation, and enhancing the anti-forward electrostatic discharge breakdown capability of the light-emitting diode; the distance a from the edge of the second electrode 202 projected on the second epitaxial structure 12 to the edge of the second step top surface is 30-45 μm, which can avoid the second electrode being too close to the edge of the epitaxial structure, so that the current is more uniformly distributed in the second epitaxial structure, and the current distribution is optimized. Through test verification, the light-emitting diode provided in the embodiment of the present disclosure has better anti-forward electrostatic discharge breakdown capability, and the yield of the light-emitting diode is improved.

[0052] Exemplarily, the distance a from the edge of the second electrode 202 projected on the second epitaxial structure 12 to the edge of the second step top surface is 35 μm.

[0053] In the embodiment of the present disclosure, the light-emitting diode includes a second current blocking layer 105, a first transparent conductive layer 106, a second transparent conductive layer, and a first electrode.

[0054] The first current blocking layer 104 extends from the first step structure 1001 to the second step structure 1002, one side of the first current blocking layer 104 is located at the first step top surface, the middle part of the first current blocking layer 104 is located at the first step bottom surface and the groove 1003, the other side of the first current blocking layer 104 is located at the second step bottom surface, and the second current blocking layer 105 is located at the second step top surface. The first transparent conductive layer 106 is located at the first step top surface and covers the part of the first current blocking layer 104 located at the first step top surface, and the second transparent conductive layer 107 is located at the second step top surface and covers the second current blocking layer 105; the first electrode 201 is located at the first step bottom surface, the second electrode 202 is located on the second transparent conductive layer 107, and the connecting electrode 203 extends from the first step structure 1001 to the second step structure 1002, one side of the connecting electrode 203 is located at the first transparent conductive layer 106, the middle part of the connecting electrode 203 is located at the first current blocking layer 104, and the other side of the connecting electrode 203 is located at the second step bottom surface.

[0055] Figure 3 is a top view of a light-emitting diode provided by an embodiment of the present disclosure. Referring to Figure 3 , Figure 1 is a cross-sectional view of A-A' in Figure 3 Figure 2 is a cross-sectional view of B-B' in Figure 3 .

[0056] In the embodiment of the present disclosure, the light-emitting diode comprises two circular second electrodes 202.

[0057] In this implementation, the circular pattern is more conducive to current diffusion, making the current spread more uniform, and the two second electrodes can better cooperate with the two connecting electrodes to achieve the effect of current spreading on the two epitaxial structures.

[0058] In the embodiment of the present disclosure, the two circular second electrodes 202 are symmetrical about a straight line z parallel to the long side of the light-emitting diode.

[0059] In this implementation, the two circular second electrodes are symmetrical about a straight line parallel to the long side of the light-emitting diode, which can make the current distribution on the second epitaxial structure more uniform and optimize the current distribution.

[0060] In the embodiment of the present disclosure, the radius of the two circular second electrodes 202 can be 15-20 μm.

[0061] Exemplarily, the radius of the two circular second electrodes 202 is 17 μm.

[0062] ​In other embodiments, the light emitting diode can further include 3 or more second electrodes 202, which can be arranged in a triangular shape, a rectangular shape, or a uniform horizontal one-dimensional arrangement.

[0063] In other embodiments, the second electrode 202 can also have other shapes, such as a rectangular shape.

[0064] In the embodiments of the present disclosure, the light emitting diode can include 1 first electrode 201.

[0065] In other implementations, the light emitting diode can further include 2 or more first electrodes 201.

[0066] In the embodiments of the present disclosure, the light emitting diode includes 2 first current blocking layers 104 and 2 connecting electrodes 203, which are one-to-one corresponding. The 2 first current blocking layers 104 are arranged at intervals.

[0067] In the embodiments of the present disclosure, the connecting electrode 203 is a long strip shape, and the first current blocking layer 104 is a long strip shape.

[0068] The width of the middle part of the connecting electrode 203 is greater than the width of the two sides, and the width of one side of the first current blocking layer 104 is less than the width of the other side.

[0069] In this implementation, the 2 connecting electrodes connect the first transparent conductive layer and the second step bottom surface, which can improve the current expansion and improve the quantum efficiency. The 2 first current blocking layers are used as insulation between the 2 connecting electrodes and the first step bottom surface, and the 2 first current blocking layers can better avoid current accumulation at the step top surface. The width of the middle part of the connecting electrode is greater than the width of the two sides, so that the middle part has a larger current expansion area to avoid current congestion at the groove. The current of the light emitting diode is prone to congestion at the groove, and the current blocking layer adopts the above shape, which can improve the current blocking ability at the groove and prevent current accumulation at the groove.

[0070] In other implementations, the light emitting diode can also include 1 connecting electrode 203 or 3 or more connecting electrodes 203.

[0071] In other implementations, the light emitting diode can also include 1 first current blocking layer 104 or 3 or more first current blocking layers 104.

[0072] Again referring to Figure 3 , the projection of the side of the second step top surface facing the first epitaxial structure 11 on the second step bottom surface is arranged in a ladder shape symmetrically on both sides; the other side of the 2 connecting electrodes 203 has a bending structure corresponding to the ladder shape.

[0073] In the implementation, the stepped structure of the epitaxial structure and the bent structure of the electrode structure can make the current flow through more areas of the epitaxial layer compared to the rectangular and straight line structures, thereby improving the current spreading capability.

[0074] In other embodiments, the connecting electrode 203 and the first current blocking layer 104 can also be long strips with consistent widths. Alternatively, the connecting electrode 203 and the first current blocking layer 104 are trapezoids with gradually changing widths, or other regular or irregular shapes.

[0075] Figure 4 is a top view of a light emitting diode provided by an embodiment of the present disclosure. Referring to Figure 4 , the projection of the side of the second step top surface facing the first epitaxial structure 11 on the second step bottom surface is a convex shape; the other side of the two connecting electrodes 203 is located at the two notches of the convex shape.

[0076] In the implementation, the second step structure adopts a convex shape, and the two connecting electrodes are located at the two notches on the two sides of the convex shape, which facilitates the arrangement of the connecting electrodes and the first current blocking layer structure, so that the current covers a larger epitaxial area when flowing between the electrodes, thereby avoiding current crowding.

[0077] In an embodiment of the present disclosure, the connecting electrode 203 is a long strip and the first current blocking layer 104 is a long strip; the width of the connecting electrode 203 gradually increases from one side to the other side, and the width of one side of the first current blocking layer 104 is smaller than the width of the other side.

[0078] In the implementation, the connecting electrode adopts the above shape, so that the middle part of the light emitting diode and the edge of the epitaxial structure have a larger current spreading area, thereby avoiding current crowding in the middle part of the light emitting diode and the edge of the epitaxial structure, and the current blocking layer adopts the above shape, which can improve the current blocking capability at the recess, thereby preventing current from gathering at the recess.

[0079] In other embodiments, the connecting electrode 203 and the first current blocking layer 104 can also be long strips with consistent widths. Alternatively, the connecting electrode 203 and the first current blocking layer 104 are trapezoids with gradually changing widths, or other regular or irregular shapes.

[0080] Figure 4 The width ratio of the first current blocking layer 104 and the connecting electrode 203 in Figure 3 The width of the first current blocking layer 104 and the connecting electrode 203 in

[0081] Exemplarily, Figure 4 The width ratio of the first current blocking layer 104 and the connecting electrode 203 in Figure 3 The width of the first current blocking layer 104 and the connecting electrode 203 in

[0082] In the embodiments of the present disclosure, Figure 3 The width of the connecting electrode 203 can be 7-17 μm, and the width of the first current blocking layer 104 can be 27-41 μm.

[0083] Figure 4 The width of the connecting electrode 203 can be 5-25 μm, and the width of the first current blocking layer 104 can be 25-49 μm.

[0084] Exemplarily, Figure 3 The width of the connecting electrode 203 can be 10 μm, and the width of the first current blocking layer 104 can be 30 μm.

[0085] Figure 4 The width of the connecting electrode 203 can be 18 μm, and the width of the first current blocking layer 104 can be 38 μm.

[0086] In the implementation manner, Figure 4 The width of the first current blocking layer and the connecting electrode is wider than the width of the first current blocking layer and the connecting electrode by 5-10 μm. Figure 3 The width of the first current blocking layer and the connecting electrode is wider than the width of the first current blocking layer and the connecting electrode by 5-10 μm.

[0087] Referring again to Figure 3 The first step top surface is in the shape of a concave character, and the first electrode 201 is located in the gap of the concave character. Figure 4 The first step top surface is in the shape of a concave character, and the first electrode 201 is located in the gap of the concave character.

[0088] In the implementation manner, the first step top surface is in the shape of a concave character, which is beneficial to uniform distribution of current and improves current spreading capability.

[0089] In the embodiments of the present disclosure, the first epitaxial structure 11 and the second epitaxial structure 12 each include a first semiconductor layer 101, an active layer 102, and a second semiconductor layer 103 stacked in sequence, the first step top surface and the second step top surface are located in the second semiconductor layer 103, and the first step bottom surface and the second step bottom surface are located in the first semiconductor layer 101.

[0090] In the embodiments of the present disclosure, the first semiconductor layer 101 can be an N-type semiconductor layer, and the second semiconductor layer 103 can be a P-type semiconductor layer.

[0091] For example, the first semiconductor layer 101 can be an N-type GaN layer, and the second semiconductor layer 103 can be a P-type GaN layer.

[0092] In the embodiments of the present disclosure, the active layer 102 can be a multi-quantum well layer, for example, an InGaN / GaN multi-quantum well layer.

[0093] In other embodiments, the first semiconductor layer 101 can be a P-type semiconductor layer, and the second semiconductor layer 103 can be an N-type semiconductor layer.

[0094] In embodiments of the present disclosure, the first current blocking layer 104 and the second current blocking layer 105 can be Al2O3, SiN or SiO2 layers.

[0095] Exemplarily, the first current blocking layer 104 and the second current blocking layer 105 are SiO2 current blocking layers.

[0096] In embodiments of the present disclosure, the first transparent conductive layer 106 and the second transparent conductive layer 107 can be Indium Tin Oxide (ITO) layers. ITO has good transparency and conductivity, and can conduct current to form an electrical connection while allowing light to pass through.

[0097] In embodiments of the present disclosure, the first electrode 201 can be a P electrode, and the second electrode 202 can be an N electrode.

[0098] In other embodiments, the first electrode 201 can be an N electrode, and the second electrode 202 can be a P electrode.

[0099] In embodiments of the present disclosure, the first electrode 201, the second electrode 202 and the connecting electrode 203 can be Cr, Al, Ti, Ni, Pt or Au electrodes.

[0100] Alternatively, the first electrode 201, the second electrode 202 and the connecting electrode 203 can be a laminated electrode of at least two of Cr, Al, Ti, Ni, Pt and Au.

[0101] Exemplarily, the first electrode 201, the second electrode 202 and the connecting electrode 203 are Cr electrodes.

[0102] In embodiments of the present disclosure, the light-emitting diode can further include a substrate 100, a passivation layer 108, a first electrode pad 301 and a second electrode pad 302.

[0103] In embodiments of the present disclosure, the first epitaxial structure 11 and the second epitaxial structure 12 are located on the substrate 100, the passivation layer 108 covers the substrate 100, the first epitaxial structure 11, the second epitaxial structure 12, the first transparent conductive layer 106, the second transparent conductive layer 107, the first electrode 201, the second electrode 202 and the connecting electrode 203, the first electrode pad 301 is connected with the first electrode 201 through the passivation layer 108, and the second electrode pad 302 is connected with the second electrode 202 through the passivation layer 108.

[0104] In the embodiments of the present disclosure, the substrate 100 can be any one of a sapphire substrate, a Si substrate, a SiC substrate, and the like, and the embodiments of the present disclosure do not limit the material of the substrate 100.

[0105] Exemplarily, the substrate 100 is a sapphire substrate.

[0106] In the embodiments of the present disclosure, the passivation layer 108 can be SiO2, Si3N4, SiN x , SiON, or a Distributed Bragg Reflector (DBR) layer, where x is greater than 0, and the DBR layer is a stack of SiO2and TiO2.

[0107] Exemplarily, the passivation layer 108 is a DBR layer.

[0108] In the embodiments of the present disclosure, the first electrode pad 301 is a convex shape.

[0109] In other embodiments, the first electrode pad 301 can also be other shapes, for example, a rectangular shape.

[0110] In the embodiments of the present disclosure, the second electrode pad 302 is a rectangular shape.

[0111] In other embodiments, the second electrode pad 302 can also be other shapes, for example, a convex shape.

[0112] In the embodiments of the present disclosure, the first electrode pad 301 and the second electrode pad 302 can be Cr, Al, Ti, Ni, Pt, AuSn, or Au electrode pads.

[0113] Alternatively, the first electrode pad 301 and the second electrode pad 302 can be a stack electrode pad of at least two of Cr, Al, Ti, Ni, Pt, AuSn, and Au.

[0114] Exemplarily, the first electrode pad 301 and the second electrode pad 302 are Cr electrode pads.

[0115] Figure 5 The first current blocking layer of the light-emitting diode provided in the embodiments of the present disclosure Figure 4 provides a projection schematic view of the first current blocking layer on the substrate. Referring to Figure 4 and Figure 5 , the light-emitting diode further includes a substrate 100, and the projection of the first current blocking layer 104 on the substrate 100 after being scaled by 0.8 to 1.2 times is located within a closed first curve, and the first curve includes 13 connected line segments Si, 1≤i≤13.

[0116] The line segments S1, S3, S6, S8, S10 and S12 are circular arcs, and the line segments S2, S4, S5, S7, S9, S11 and S13 are straight lines.

[0117] The angle α of the circular arc of the line segments S1, S3, S6, S8, S10 and S12 is respectively 180.0±3°, 22.0±3°, 90.0±3°, 90.0±3°, 45.0±3° and 45±3°.

[0118] The angle α of the circular arc of the line segments S1, S3, S6, S8, S10 and S12 is respectively 180.0±3°, 22.0±3°, 90.0±3°, 90.0±3°, 45.0±3° and 45±3°.

[0119] The rotation direction of the line segments S1, S3, S6, S8, S10 and S12 is respectively counterclockwise, clockwise, counterclockwise, counterclockwise, counterclockwise and clockwise.

[0120] In the implementation mode, the projection of the first current blocking layer on the substrate is located in the closed first curve after being scaled by 0.8 to 1.2 times, the first current blocking layer adopts a circular arc and a straight line, and the circular arc angle adopts the above-mentioned numerical value, which can avoid current aggregation on the step top surface of the first current blocking layer. According to the ESD test data, the yield of the light-emitting diode provided by the embodiment of the present disclosure is still greater than 90% at 8500V. Figure 4 The test data of the light-emitting diode provided by the embodiment of the present disclosure is still greater than 90% at 8500V.

[0121] In the embodiment of the present disclosure, the radius R of the line segments S1, S3, S6, S8, S10 and S12 is respectively 12.5±2μm, 10.0±2μm, 6.0±2μm, 6.0±2μm, 10.0±2μm and 10.0±2μm.

[0122] In the implementation mode, the line segments of the first current blocking layer adopt the above-mentioned radius, which is beneficial to the graphical arrangement of the first curve, and the radius can optimize the current distribution and further enhance the anti-forward electrostatic discharge breakdown capability of the light-emitting diode.

[0123] In the embodiment of the present disclosure, the length L of the line segments S2, S4, S5, S7, S9, S11 and S13 is respectively 12.5±2μm, 18.5±2μm, 28.0±2μm, 37.0±2μm, 21.3±2μm, 14.6±2μm and 59±2μm.

[0124] In the implementation mode, the line segments of the first current blocking layer adopt the above-mentioned length, which can be combined with the above-mentioned curve line segments to form the first curve, thereby optimizing the current distribution.

[0125] Figure 6 is the projection of the connecting electrode of the light-emitting diode provided by the embodiment of the present disclosure on the substrate. Figure 4 is the projection of the connecting electrode of the light-emitting diode provided by the embodiment of the present disclosure on the substrate. Figure 4 and Figure 6The light emitting diode further comprises a substrate 100, and a projection of the connecting electrode 203 on the substrate is located in a closed second curve after being scaled by 0.8 to 1.2 times, the second curve comprises 22 line segments Si connected in a loop, and 1≤i≤22.

[0126] The line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are circular arcs, and the line segments S2, S4, S6, S8, S10, S12, S14, S16, S18, S20 and S22 are straight lines.

[0127] The circular arc angles α of the line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are respectively 180.0±3°, 20.0±3°, 20.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 50.0±3° and 50±3°.

[0128] The rotation directions of the line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are respectively counterclockwise, clockwise, counterclockwise, clockwise, counterclockwise, counterclockwise, counterclockwise, counterclockwise, clockwise, counterclockwise and clockwise.

[0129] In the implementation, the projection of the connecting electrode on the substrate is located in the closed second curve after being scaled by 0.8 to 1.2 times, the connecting electrode adopts the circular arcs and the straight lines, and the circular arc angles adopt the above values, so that the connecting electrode has a larger current expansion area to avoid current congestion at the groove, and the current blocking layer adopts the above shape, so that the current blocking capacity at the groove is improved to prevent the current from gathering at the groove. According to ESD test data, the yield of the light emitting diode provided in the embodiment of the present disclosure is greater than 90% at 8500V. Figure 4 The test data of the light emitting diode provided in the embodiment of the present disclosure is greater than 90% at 8500V.

[0130] In the embodiment of the present disclosure, the values of the radii R of the line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are respectively 2.5±2μm, 20.0±2μm, 5.0±2μm, 5.0±2μm, 3.0±2μm, 3.0±2μm, 3.0±2μm, 3.0±2μm, 5.0±2μm, 10.0±2μm and 20.0±2μm.

[0131] In the implementation, the line segments of the connecting electrode adopt the above radii, which is beneficial to the graphical arrangement of the second curve, and the radii can optimize the current distribution of the connecting electrode to further enhance the anti-forward electrostatic discharge breakdown capability of the light emitting diode.

[0132] In the embodiments of the present disclosure, the lengths L of the line segments S2, S4, S6, S8, S10, S12, S14, S16, S18, S20 and S22 are respectively 57.4±2 μm, 13.0±2 μm, 23.0±2 μm, 1.0±2 μm, 1.0±2 μm, 37.0±2 μm, 1.0±2 μm, 1.0±2 μm, 19.0±2 μm, 4.0±2 μm and 102.0±2 μm.

[0133] In the implementation, the line segments of the connecting electrodes adopt the above lengths, which can form the second curve together with the above curved line segments, so as to further optimize the current distribution of the light-emitting diode, prevent the current from gathering at the edge of the light-emitting diode, and further enhance the anti-forward electrostatic discharge breakdown capability of the light-emitting diode.

[0134] Figure 7 is a flow chart of a light-emitting diode preparation method provided by the embodiments of the present disclosure. Referring to Figure 7 , the method steps include:

[0135] S101, a first epitaxial structure and a second epitaxial structure are made, the first epitaxial structure includes a first step structure, the first step structure includes a first step bottom surface and a first step top surface, the second epitaxial structure includes a second step structure, the second step structure includes a second step bottom surface and a second step top surface, and the first epitaxial structure and the second epitaxial structure have a groove therebetween.

[0136] S102, a first current blocking layer and a second current blocking layer are made, the first current blocking layer extends from the first step structure to the second step structure, one side of the first current blocking layer is located at the first step top surface, a middle part of the first current blocking layer is located at the first step bottom surface and the groove, and the other side of the first current blocking layer is located at the second step bottom surface, and the second current blocking layer is located at the second step top surface.

[0137] S103, a first transparent conductive layer and a second transparent conductive layer are made, the first transparent conductive layer is located at the first step top surface and covers the part of the first current blocking layer located at the first step top surface, and the second transparent conductive layer is located at the second step top surface and covers the second current blocking layer.

[0138] S104, a first electrode, a second electrode and a connecting electrode are made, the first electrode is located at the first step bottom surface, the second electrode is located on the second transparent conductive layer, the connecting electrode extends from the first step structure to the second step structure, one side of the connecting electrode is located at the first transparent conductive layer, a middle part of the connecting electrode is located at the first current blocking layer, and the other side of the connecting electrode is located at the second step bottom surface.

[0139] In the embodiments of the present disclosure, the light emitting diode comprises a first epitaxial structure and a second epitaxial structure, both of which are in a stepped shape, wherein a first current blocking layer extends from a first stepped structure to a second stepped structure, one side of the first current blocking layer is located at a first stepped top surface, a middle part of the first current blocking layer is located at a first stepped bottom surface and a groove, the other side of the first current blocking layer is located at a second stepped bottom surface, and a second current blocking layer is located at a second stepped top surface, wherein the first current blocking layer is used as insulation between the connecting electrode and the first stepped bottom surface, and the first current blocking layer and the second current blocking layer can avoid current concentration at the respective stepped top surfaces. A first transparent conductive layer is located at the first stepped top surface and covers the part of the first current blocking layer located at the first stepped top surface, and a second transparent conductive layer is located at the second stepped top surface and covers the second current blocking layer, the first transparent conductive layer and the second transparent conductive layer can expand the current at the respective stepped top surfaces, improve the current distribution, and optimize the electric field. The first electrode, the second electrode and the connecting electrode realize the series connection between the two epitaxial layers, divide the epitaxial layer into two parts and then connect them through the connecting electrode, the two epitaxial layers divide the current into two paths, the two paths of current are transmitted to the other side epitaxial layer, and the current expansion effect is improved on the other side epitaxial layer, the current concentration is prevented, and the anti-forward electrostatic discharge breakdown capability of the light emitting diode is enhanced.

[0140] Figure 8 is another flow chart of a method for manufacturing a light emitting diode provided by the embodiments of the present disclosure. Referring to Figure 8 , the method steps include:

[0141] S201, forming a first semiconductor layer, an active layer and a second semiconductor layer on a substrate in sequence, the first semiconductor layer, the active layer and the second semiconductor layer forming an epitaxial structure.

[0142] The substrate can be a sapphire substrate.

[0143] In an example, step S201 includes:

[0144] First, the first semiconductor layer is made.

[0145] In the embodiments of the present disclosure, the first semiconductor layer can be an N-type semiconductor layer. For example, the first semiconductor layer can be an N-type GaN layer.

[0146] In other embodiments, the first semiconductor layer can be a P-type semiconductor layer.

[0147] Second, the active layer is made.

[0148] In the embodiments of the present disclosure, the active layer is a multi-quantum well layer. For example, an InGaN / GaN multi-quantum well layer.

[0149] Thirdly, a second semiconductor layer is prepared.

[0150] In the embodiments of the present disclosure, the second semiconductor layer can be a P-type semiconductor layer. For example, the second semiconductor layer can be a P-type GaN layer.

[0151] In other embodiments, the second semiconductor layer can be an N-type semiconductor layer.

[0152] In the embodiments of the present disclosure, the first semiconductor layer, the active layer and the second semiconductor layer are sequentially stacked on the substrate.

[0153] In the embodiments of the present disclosure, the growth of the semiconductor layers can be realized by using a Veeco K465i or C4 or RB MOCVD (Metal Organic Chemical Vapor Deposition) device or an AIXTRON metal organic chemical vapor deposition device. High-purity H2 (hydrogen) or high-purity N2 (nitrogen) or a mixed gas of high-purity H2 and high-purity N2 is used as a carrier gas, high-purity NH3 is used as an N source, trimethyl gallium (TMGa) and triethyl gallium (TEGa) are used as gallium sources, trimethyl indium (TMIn) is used as an indium source, silane (SiH4) is used as an N-type dopant, trimethyl aluminum (TMAl) is used as an aluminum source, and dimethyl magnesium (CP2Mg) is used as a P-type dopant.

[0154] It should be noted that other devices can also be used to prepare the semiconductor layers, and the present disclosure does not limit this.

[0155] S202, performing a patterning process on the epitaxial structure to form a first epitaxial structure and a second epitaxial structure, the first epitaxial structure being a first step structure, the first step structure having a first step bottom surface and a first step top surface, the second epitaxial structure being a second step structure, the second step structure having a second step bottom surface and a second step top surface, and the first epitaxial structure and the second epitaxial structure having a groove therebetween.

[0156] In the embodiments of the present disclosure, a projection of a side of the second step top surface facing the first epitaxial structure on the second step bottom surface is a ladder-shaped structure arranged symmetrically on two sides; the other side of the two connecting electrodes has a bending structure corresponding to the ladder-shaped structure.

[0157] This arrangement of the ladder-shaped structure of the epitaxial structure and the bending structure of the electrode structure enables the current to flow through more areas of the epitaxial structure compared to using a rectangular and straight line structure, thereby improving the current spreading capability.

[0158] In the embodiments of the present disclosure, a projection of a side of the second step top surface facing the first epitaxial structure on the second step bottom surface is a convex shape.

[0159] In the implementation, the second step structure adopts a convex shape, which is beneficial to the arrangement of the connecting electrode and the first current blocking layer structure, so that the epitaxial area covered by the current is larger when the current flows between the electrodes, and the current is avoided from gathering.

[0160] In the embodiment of the present disclosure, a projection of the first step top surface away from one side of the second epitaxial structure on the first step bottom surface is in a concave shape.

[0161] In the implementation, the first step top surface adopts a concave shape, which is beneficial to the uniform distribution of the current and improves the current spreading capability.

[0162] S203, a first current blocking layer and a second current blocking layer are respectively made on the first epitaxial structure and the second epitaxial structure, the first current blocking layer extends from the first step structure to the second step structure, one side of the first current blocking layer is located on the first step top surface, the middle part of the first current blocking layer is located on the first step bottom surface and the groove, the other side of the first current blocking layer is located on the second step bottom surface, and the second current blocking layer is located on the second step top surface.

[0163] Exemplarily, the step S203 can include:

[0164] Firstly, a current blocking film layer is deposited.

[0165] In the embodiment of the present disclosure, the current blocking film layer can be an Al2O3, SiN or SiO2 layer.

[0166] Exemplarily, the current blocking film layer is a SiO2 current blocking film layer.

[0167] Secondly, a layer of photoresist is coated on the current blocking film layer.

[0168] Thirdly, the photoresist is exposed.

[0169] Fourthly, the current blocking film layer is etched to form the first current blocking layer and the second current blocking layer.

[0170] In the embodiment of the present disclosure, the current blocking film layer is etched by using a buffered oxide etching (BOE).

[0171] Exemplarily, the first current blocking layer and the second current blocking layer are SiO2 current blocking layers.

[0172] In the embodiment of the present disclosure, the light emitting diode includes two first current blocking layers, and the two first current blocking layers are arranged at intervals.

[0173] In the implementation, the two first current blocking layers are used as insulation between the two connection electrodes and the first step bottom surface, and the two first current blocking layers can better avoid current accumulation at the step top surface.

[0174] In other implementations, the light emitting diode can also include one first current blocking layer or three or more first current blocking layers.

[0175] In the embodiments of the present disclosure, the first current blocking layer is a long strip shape; the width of one side of the first current blocking layer is smaller than the width of the other side.

[0176] In the implementation, the current is prone to crowding at the groove of the light emitting diode, and the current blocking layer adopts the above shape, which can improve the current blocking capability at the groove and prevent current accumulation at the groove.

[0177] In other embodiments, the first current blocking layer can also be a long strip shape with consistent width. Alternatively, the first current blocking layer is a trapezoidal shape with gradually changing width, or other regular or irregular shapes.

[0178] S204, a first transparent conductive layer and a second transparent conductive layer are respectively made on the first current blocking layer and the second current blocking layer, the first transparent conductive layer is located on the first step top surface and covers the part of the first current blocking layer located on the first step top surface, and the second transparent conductive layer is located on the second step top surface and covers the second current blocking layer.

[0179] Exemplarily, the step S204 can include:

[0180] Firstly, a layer of transparent conductive film is deposited on the first current blocking layer and the second current blocking layer respectively.

[0181] In the embodiments of the present disclosure, the transparent conductive film layer can be an ITO layer, which has good transparency and conductivity and can conduct current to form electrical connection while allowing light to pass through.

[0182] Secondly, a layer of photoresist is coated on the transparent conductive film layer.

[0183] Thirdly, the photoresist is exposed.

[0184] Fourthly, the transparent conductive film layer is etched to form the first transparent conductive layer and the second transparent conductive layer.

[0185] S205, a first electrode, a second electrode and a connection electrode are made, the first electrode is located on the first step bottom surface, the second electrode is located on the second transparent conductive layer, the connection electrode extends from the first step structure to the second step structure, one side of the connection electrode is located on the first transparent conductive layer, the middle part of the connection electrode is located on the first current blocking layer, and the other side of the connection electrode is located on the second step bottom surface.

[0186] In the embodiments of the present disclosure, the first electrode, the second electrode and the connecting electrode are formed by metal evaporation.

[0187] In the embodiments of the present disclosure, the light emitting diode includes two second electrodes in the shape of a circle with a radius of 15-20 μm, which are arranged at intervals on the top surface of the second step of the second epitaxial structure, and the distance between the second electrode and the edge of the top surface of the second step can be 30-45 μm.

[0188] In this implementation, the two second electrodes arranged at intervals can make the current distribution more uniform in the second epitaxial structure, and the circular pattern is more conducive to the diffusion of the current, so that the current is more uniformly expanded. The above-mentioned radius and distance can avoid the second electrode being too close to the edge of the epitaxial structure, and optimize the current distribution. Moreover, the two second electrodes can better cooperate with the two connecting electrodes to achieve the effect of current expansion on the two epitaxial structures.

[0189] Exemplarily, the light emitting diode includes two second electrodes in the shape of a circle with a radius of 17 μm, which are arranged at intervals on the top surface of the second step of the second epitaxial structure, and the distance between the second electrode and the edge of the top surface of the second step is 35 μm.

[0190] In other embodiments, the light emitting diode can further include three or more second electrodes, which can be arranged in a triangular shape, a rectangular shape or a horizontal one-dimensional uniform arrangement.

[0191] The light emitting diode can include one first electrode.

[0192] In other implementations, the light emitting diode can further include two first electrodes or two or more first electrodes.

[0193] In the embodiments of the present disclosure, the light emitting diode includes two connecting electrodes, and the two first current blocking layers and the two connecting electrodes are in one-to-one correspondence.

[0194] In this implementation, the two connecting electrodes connect the first transparent conductive layer and the bottom surface of the second step, which can improve the current expansion and improve the quantum efficiency.

[0195] In other implementations, the light emitting diode can also include one connecting electrode or three or more connecting electrodes.

[0196] In the embodiments of the present disclosure, the other side of the two connecting electrodes has a bending structure corresponding to the step.

[0197] In this implementation, the bending structure of the electrode structure can make the current flow through more areas of the epitaxial structure compared with the rectangular and straight line structures, thereby improving the current expansion capability.

[0198] In the embodiments of the present disclosure, the connection electrode is in a long strip shape; the width of the middle part of the connection electrode is greater than the width of the two sides.

[0199] In the implementation, the width of the middle part of the connection electrode is greater than the width of the two sides, so that the middle part has a larger current spreading area to avoid current congestion at the groove.

[0200] In other embodiments, the connection electrode can also be a long strip shape with consistent width. Alternatively, the connection electrode 203 is a trapezoidal shape with gradually changing width, or other regular or irregular shapes.

[0201] In the embodiments of the present disclosure, the other side of the two connection electrodes is located at the two notches of the convex shape.

[0202] In the implementation, the second step structure adopts a convex shape, and the two connection electrodes are located at the two notches on the two sides of the convex shape, which is beneficial to the arrangement of the connection electrode and the first current blocking layer structure, so that the epitaxial area covered by the current flowing between the electrodes is larger, and current congestion is avoided.

[0203] Referring to Figure 4 , the connection electrode is in a long strip shape; the width of the connection electrode 203 gradually increases from one side to the other side.

[0204] In the implementation, the connection electrode adopts the above shape, so that the middle part of the light emitting diode and the edge of the epitaxial structure have a larger current spreading area, and current congestion at the middle part of the light emitting diode and the edge of the epitaxial structure is avoided.

[0205] In the embodiments of the present disclosure, the first electrode can be a P electrode, and the second electrode can be an N electrode.

[0206] In other embodiments, the first electrode can be an N electrode, and the second electrode can be a P electrode.

[0207] In the embodiments of the present disclosure, the first electrode, the second electrode and the connection electrode can be Cr, Al, Ti, Ni, Pt or Au electrodes.

[0208] Alternatively, the first electrode, the second electrode and the connection electrode can be a stacked electrode of at least two of Cr, Al, Ti, Ni, Pt and Au.

[0209] Exemplarily, the first electrode, the second electrode and the connection electrode are Cr electrodes.

[0210] S206, a passivation layer is made, which covers the substrate, the first epitaxial structure, the second epitaxial structure, the transparent conductive layer, the first electrode, the second electrode and the connection electrode.

[0211] In the embodiments of the present disclosure, step S206 can include:

[0212] First, a passivation layer is made.

[0213] In the embodiments of the present disclosure, the passivation layer can be a passivation layer made by PECVD.

[0214] In the embodiments of the present disclosure, the passivation layer can be SiO2, Si3N4, SiN x , SiON or a DBR layer. Wherein x is greater than 0, and the DBR layer is a stack of SiO2 and TiO2.

[0215] Exemplarily, the passivation layer is a DBR layer.

[0216] Secondly, the passivation layer is opened.

[0217] In the embodiments of the present disclosure, the passivation layer has a through hole with a bottom located between the first electrode and the second electrode.

[0218] S207, a first electrode pad and a second electrode pad are made.

[0219] In the embodiments of the present disclosure, the first electrode pad is connected to the first electrode through the through hole, and the second electrode pad is connected to the second electrode through the through hole.

[0220] In the embodiments of the present disclosure, the first electrode pad and the second electrode pad are deposited by metal evaporation.

[0221] In the embodiments of the present disclosure, the first electrode pad is in the shape of a convex.

[0222] In other embodiments, the first electrode pad can also be in other shapes, such as a rectangle.

[0223] In the embodiments of the present disclosure, the second electrode pad is in the shape of a rectangle.

[0224] In other embodiments, the second electrode pad can also be in other shapes, such as a convex.

[0225] In the embodiments of the present disclosure, the first electrode pad and the second electrode pad can be Cr, Al, Ti, Ni, Pt, AuSn or Au electrode pads.

[0226] Alternatively, the first electrode pad and the second electrode pad can be a stack electrode pad of at least two of Cr, Al, Ti, Ni, Pt, AuSn and Au.

[0227] Exemplarily, the first electrode pad and the second electrode pad are Cr electrode pads.

[0228] S208, thinning the substrate.

[0229] By means of thinning, grinding and the like, the thickness of the chip is reduced to match the downstream market demand.

[0230] S209, cutting the light-emitting diode.

[0231] In the embodiments of the present disclosure, step S209 can include:

[0232] First, the light emitting diode is scribed.

[0233] In the embodiments of the present disclosure, the whole wafer is attached to the adhesive polymer film, and the back surface is scribed by a hidden cutting machine. According to the wafer structure, the cutting is performed in the order of first oblique fracture surface and then non-oblique fracture surface.

[0234] Second, the wafer is broken.

[0235] After the hidden cutting machine is processed, the wafer is broken.

[0236] Third, automated optical inspection (AOI) is performed.

[0237] Fourth, the film is expanded.

[0238] Table 1 is an embodiment of the present disclosure Figure 3 And Figure 4 Compared with the forward ESD voltage increase, brightness and voltage change value of the light emitting diode provided by the related art, as shown, ΔLop is the brightness. ΔVf represents the forward voltage change, and the unit is V.

[0239] Table 1

[0240]

[0241] From the verification data in Table 1 Figure 3 And Figure 4 Compared with the forward ESD of the light emitting diode provided by the related art, Figure 3 The forward ESD of the light emitting diode provided by the present disclosure is improved by 1.5KV, Figure 4 The forward ESD of the light emitting diode provided by the present disclosure is improved by 4KV.

[0242] Figure 9 An embodiment of the present disclosure Figure 3 And Figure 4 The current expansion of the light emitting diode provided by the present disclosure is intended. Referring to Figure 9 , the left side corresponds to the structure of Figure 3 , and the right side corresponds to the structure of Figure 4 . From Figure 9It can be seen that the two second electrodes ensure good diffusion effect of the current in the second epitaxial structure, the current is transmitted to the first epitaxial structure through the two connecting electrodes, and the two connecting electrodes ensure good diffusion effect of the current in the first epitaxial structure. Through the above structure, the current diffusion is more uniform, and the degree of aggregation of the current at the edge of the epitaxial structure is smaller, which prevents the aggregation of the current and enhances the positive static discharge breakdown resistance of the light emitting diode.

[0243] The following Table 2 is Figure 5 The line segment size table of the first current blocking layer of the light emitting diode provided is provided. Wherein, R is the radius of the circular arc, a is the angle of the circular arc, and L is the length of the straight line.

[0244] Table 2

[0245] Curve number R (pm) α(°) L (pm) Direction of rotation S1 12.5 180.0 / Counter clockwise S2 / / 12.5 Positive direction S3 10.0 22.0 / Clockwise S4 / / 18.5 Positive direction S5 / / 28.0 Positive direction S6 6.0 90.0 / Counter clockwise S7 / / 37.0 Negative direction S8 6.0 90.0 / Counter clockwise S9 / / 21.3 Negative direction S10 10.0 45.0 / Counter clockwise S11 / / 14.6 Negative direction S12 10.0 45.0 / Clockwise S13 / / 59 Negative direction

[0246] The following Table 3 is Figure 5 The line segment size table of the connecting electrode of the light emitting diode provided is provided. Wherein, R is the radius of the circular arc, a is the angle of the circular arc, and L is the length of the straight line.

[0247] Table 3

[0248]

[0249]

[0250] In actual situations, the size of the light emitting diode is usually enlarged by a certain percentage for the purpose of improving the brightness of the light emitting diode and other considerations. At this time, the layout used by the light emitting diode is also enlarged by the same percentage. However, when the size of the light emitting diode is enlarged beyond a certain size, the layout needs to be redesigned. For the embodiments of the present disclosure, when the light emitting diode is scaled by 0.8 to 1.2 times, the layout used by the light emitting diode is also scaled by the same ratio. At the same time, considering the process error, the length value can be permitted within ±2μm, and the angle value of the circular arc can be permitted within ±3°.

[0251] As shown in the following Table 4, the yield of the light emitting diode provided by the related art is less than 90% at 5000V in the ESD test data. The light emitting diode provided by the embodiments of the present disclosure Figure 3 The yield of the light emitting diode provided by the embodiments of the present disclosure is less than 90% at 6500V in the test data. The yield of the light emitting diode provided by the embodiments of the present disclosure Figure 4 The yield of the light emitting diode provided by the embodiments of the present disclosure is still greater than 90% at 8500V. From the above test data, it can be concluded that the yield of the light emitting diode provided by the embodiments of the present disclosure is improved.

[0252] Table 4

[0253]

[0254] The above merely provides the optional embodiments of the present disclosure, but does not intend to limit the present disclosure. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A light-emitting diode, characterized in that, The light-emitting diode includes: a first epitaxial structure (11), a second epitaxial structure (12), a first current blocking layer (104), a second electrode (202), and a connecting electrode (203); The first epitaxial structure (11) includes a first step structure (1001), which includes a first step bottom surface and a first step top surface; the second epitaxial structure (12) includes a second step structure (1002), which includes a second step bottom surface and a second step top surface; a groove (1003) is provided between the first epitaxial structure (11) and the second epitaxial structure (12); the first current blocking layer (104) extends from the first step structure (1001) to the second step structure (1002), and the connecting electrode (203) is located on the first current blocking layer (104) and is electrically connected to the first epitaxial structure (11) and the second epitaxial structure (12) respectively; The distance from the edge of the projection of the second electrode (202) onto the second epitaxial structure (12) to the edge of the top surface of the second step is 30-45 μm.

2. The light-emitting diode according to claim 1, characterized in that, The light-emitting diode includes two circular second electrodes (202).

3. The light-emitting diode according to claim 2, characterized in that, The two circular second electrodes (202) are symmetrical about a straight line parallel to the long side of the light-emitting diode.

4. The light-emitting diode according to any one of claims 1 to 3, characterized in that, The light-emitting diode includes two first current blocking layers (104) and two connecting electrodes (203), with the two first current blocking layers (104) and the two connecting electrodes (203) corresponding one-to-one; the two first current blocking layers (104) are spaced apart; The connecting electrode (203) is elongated, and the first current blocking layer (104) is elongated. The width of the middle part of the connecting electrode (203) is greater than the width of both sides, and the width of one side of the first current blocking layer (104) is less than the width of the other side.

5. The light-emitting diode according to any one of claims 1 to 3, characterized in that, The light-emitting diode also includes a substrate (100), and the projection of the first current blocking layer (104) on the substrate (100) is scaled by 0.8 to 1.2 times and located within a closed first curve. The first curve includes 13 line segments Si connected end to end, 1≤i≤13. The line segments S1, S3, S6, S8, S10 and S12 are arcs, and the line segments S2, S4, S5, S7, S9, S11 and S13 are straight lines; The arc angle α of line segments S1, S3, S6, S8, S10 and S12 are 180.0±3°, 22.0±3°, 90.0±3°, 90.0±3°, 45.0±3° and 45±3° respectively. The rotation directions of line segments S1, S3, S6, S8, S10 and S12 are respectively: counterclockwise, clockwise, counterclockwise, counterclockwise, counterclockwise and clockwise.

6. The light-emitting diode according to claim 5, characterized in that, The radius R of the line segments S1, S3, S6, S8, S10 and S12 are 12.5±2μm, 10.0±2μm, 6.0±2μm, 6.0±2μm, 10.0±2μm and 10.0±2μm, respectively.

7. The light-emitting diode according to claim 5, characterized in that, The lengths L of the line segments S2, S4, S5, S7, S9, S11 and S13 are 12.5±2μm, 18.5±2μm, 28.0±2μm, 37.0±2μm, 21.3±2μm, 14.6±2μm and 59±2μm, respectively.

8. The light-emitting diode according to any one of claims 1 to 3, characterized in that, The light-emitting diode also includes a substrate (100), and the projection of the connecting electrode (203) on the substrate is scaled by 0.8 to 1.2 times and located within a closed second curve. The second curve includes 22 line segments Si connected end to end, where 1≤i≤22. The line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are arcs, and the line segments S2, S4, S6, S8, S10, S12, S14, S16, S18, S20 and S22 are straight lines. The arc angle α of line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are 180.0±3°, 20.0±3°, 20.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 90.0±3°, 50.0±3° and 50±3° respectively. The rotation directions of line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are respectively: counterclockwise, clockwise, counterclockwise, clockwise, counterclockwise, counterclockwise, counterclockwise, counterclockwise, clockwise, counterclockwise and clockwise.

9. The light-emitting diode according to claim 8, characterized in that, The radius R of the line segments S1, S3, S5, S7, S9, S11, S13, S15, S17, S19 and S21 are 2.5±2μm, 20.0±2μm, 5.0±2μm, 5.0±2μm, 3.0±2μm, 3.0±2μm, 3.0±2μm, 3.0±2μm, 5.0±2μm, 10.0±2μm and 20.0±2μm, respectively.

10. The light-emitting diode according to claim 8, characterized in that, The lengths L of the line segments S2, S4, S6, S8, S10, S12, S14, S16, S18, S20 and S22 are 57.4±2μm, 13.0±2μm, 23.0±2μm, 1.0±2μm, 1.0±2μm, 37.0±2μm, 1.0±2μm, 1.0±2μm, 19.0±2μm, 4.0±2μm and 102.0±2μm, respectively.

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