LED chip and manufacturing method thereof

Abstract

The invention relates to an LED chip and a manufacturing method thereof. A second type semiconductor layer of the LED chip comprises a first region and a remaining second region, wherein the first region is over against a second electrode; the current blocking protection layer group comprises a blocking layer and a protection layer; the barrier layer is located in the first region; the protective layer at least covers the second region and conducts the transparent conductive layer and the second type semiconductor layer; the transparent conductive layer is only stacked on the protective layer of the second area, and the second electrode is conducted with the second type semiconductor layer through the transparent conductive layer and / or the protective layer. And the current blocking protection layer group completely covers the second type semiconductor layer, so that defects caused by the fact that plasma bombards the second type semiconductor layer when the transparent conductive layer is manufactured are avoided. The current blocking protection layer group is provided with a blocking layer and a protection layer in a regional manner, so that the current blocking protection layer group can not only protect the second type semiconductor layer, but also block current.

Description

Technical Field

[0001] The present invention relates to the technical field of light emitting diodes, and more specifically, to an LED chip and a manufacturing method thereof. Background Art

[0002] With the continuous development of science and technology, LED (Light Emitting Diode) as a new type of light-emitting device, compared with traditional light-emitting devices, LED chips have many advantages such as low power consumption, high color purity, long life, small size, fast response time, energy saving and environmental protection. It has become the most popular light source at present, with an increasing market share and a wider range of applications.

[0003] As we all know, in order to make the current have better expansion capability, a transparent conductive layer will be deposited on the surface of the semiconductor layer. At present, due to the good density, good film uniformity, strong film-base bonding, and few film defects of ITO deposited by magnetron sputtering, most transparent conductive layers are deposited by magnetron sputtering. However, the plasma in magnetron sputtering will bombard the semiconductor layer, causing defects on the surface of the semiconductor layer, affecting the reliability of the LED chip, and the ln in ITO will enter the semiconductor layer, which will not only reduce the transmittance of ITO and affect the light efficiency, but also reduce the ESD capability of the chip.

[0004] In order to avoid the above problems when the ITO layer is made by the magnetron sputtering method, this case is created. Summary of the invention

[0005] In view of this, the present invention provides an LED chip and a method for manufacturing the same, which can avoid defects on the surface of the semiconductor layer when the ITO layer is manufactured by a magnetron sputtering method, and can also prevent In in the ITO from entering the semiconductor layer.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] An LED chip, characterized by comprising:

[0008] substrate;

[0009] An epitaxial structure disposed on a surface of one side of the substrate; the epitaxial structure comprises a first-type semiconductor layer, an active layer, a second-type semiconductor layer, a current blocking protection layer group and a transparent conductive layer sequentially disposed in a direction away from the substrate;

[0010] a first electrode electrically connected to the first-type semiconductor layer;

[0011] a second electrode electrically connected to the second-type semiconductor layer;

[0012] The second-type semiconductor layer includes a first region facing the second electrode and a remaining second region; the current blocking protection layer group includes a blocking layer and a protection layer; the blocking layer is located in the first region; the protection layer at least covers the second region and conducts between the transparent conductive layer and the second-type semiconductor layer;

[0013] The transparent conductive layer is only stacked on the protective layer in the second region, and the second electrode is electrically connected to the second-type semiconductor layer through the transparent conductive layer and / or the protective layer.

[0014] Preferably, the barrier layer and the protective layer are both deposited by atomic layer deposition (ALD), and before depositing the barrier layer and the protective layer, a temporary barrier layer is deposited on the second-type semiconductor layer by chemical vapor deposition (CVD) to expose the first area; and after the barrier layer is formed by atomic layer deposition and dry etching, wet etching is used to remove the temporary barrier layer, and then the protective layer is deposited.

[0015] Preferably, the material of the protection layer is a conductive material or an insulating tunneling material.

[0016] Preferably, the thickness of the insulating tunneling material is not greater than 5 nm.

[0017] Preferably, the refractive index of the protective layer is greater than the refractive index of the transparent conductive layer, and is less than the refractive index of the second-type semiconductor layer.

[0018] Preferably, it also includes a passivation layer and a microsphere anti-reflection coating stacked on the transparent conductive layer;

[0019] The microsphere anti-reflective coating at least covers the exposed surface of the transparent conductive layer;

[0020] The transparent conductive layer is ITO;

[0021] The passivation layer is made of SiO2 material, covers the exposed surfaces of the epitaxial structure, the first electrode, the second electrode and the microsphere anti-reflection coating, and is provided with through holes exposing the electrodes.

[0022] Preferably, the microsphere anti-reflection coating contains at least two kinds of microspheres with different diameters.

[0023] Preferably, the microsphere anti-reflection coating uses SiO2 microspheres.

[0024] Preferably, the microsphere anti-reflective coating comprises SiO2 microspheres no larger than 2um, SiO2 microspheres no larger than 20nm, sodium dodecyl sulfate and anhydrous ethanol; wherein the volume ratio of SiO2 microspheres no larger than 2um: SiO2 microspheres no larger than 20nm: sodium dodecyl sulfate: anhydrous ethanol is 1:10:10:10.

[0025] The present invention also provides a method for manufacturing an LED chip, which is characterized by comprising the following steps:

[0026] providing a substrate;

[0027] Growing an epitaxial structure on the surface of one side of the substrate; growing the epitaxial structure includes sequentially growing a first-type semiconductor layer, an active layer, a second-type semiconductor layer, a current blocking protection layer group and a transparent conductive layer in a direction away from the substrate;

[0028] Making a first electrode electrically connected to the first-type semiconductor layer;

[0029] Making a second electrode electrically connected to the second-type semiconductor layer;

[0030] The second-type semiconductor layer includes a first region facing the second electrode and a remaining second region; manufacturing the current blocking protection layer group includes manufacturing a blocking layer and a protection layer; the blocking layer is located in the first region; the protection layer at least covers the second region and conducts the transparent conductive layer and the second-type semiconductor layer;

[0031] The transparent conductive layer is only stacked on the protective layer in the second region, and the second electrode is electrically connected to the second-type semiconductor layer through the transparent conductive layer and / or the protective layer.

[0032] Preferably, when manufacturing the current blocking protective layer group, the blocking layer is manufactured first, and then the protective layer is manufactured;

[0033] Before making the barrier layer, the method further includes depositing a temporary barrier material layer covering the second-type semiconductor layer by chemical vapor deposition, and performing photolithography and wet etching on the temporary barrier material layer to form a temporary barrier layer exposing the first area;

[0034] Forming a barrier material layer on the temporary barrier layer by atomic layer deposition, and performing photolithography and inductively coupled plasma (ICP) etching on the barrier material layer to form a barrier layer covering the first region;

[0035] Placing the semi-finished LED chip in a BOE etching tank for wet etching to remove the temporary barrier layer;

[0036] A protective layer covering at least the second region is deposited by atomic layer deposition.

[0037] Preferably, the material of the protection layer is a conductive material or an insulating tunneling material.

[0038] Preferably, the refractive index of the protective layer is greater than the refractive index of the transparent conductive layer, and is less than the refractive index of the second-type semiconductor layer.

[0039] Preferably, the method further comprises preparing a microsphere anti-reflection coating layer covering at least the exposed surface of the transparent conductive layer;

[0040] The transparent conductive layer is ITO;

[0041] After the first electrode and the second electrode are manufactured, a passivation layer is manufactured; the passivation layer is made of SiO2 material, covers the exposed surfaces of the epitaxial structure, the first electrode, the second electrode and the microsphere anti-reflection coating, and is provided with through holes to expose the electrodes.

[0042] Preferably, the microsphere anti-reflection coating contains at least two kinds of microspheres with different diameters.

[0043] Compared with the prior art, the technical solution provided by the present invention has at least the following advantages:

[0044] 1. The current blocking protection layer group of the LED chip of the present application completely covers the second-type semiconductor layer. When the transparent conductive layer is made by magnetron sputtering, the second-type semiconductor layer and the transparent conductive layer are isolated to prevent plasma bombardment on the second-type semiconductor layer to produce defects, thereby increasing the reliability of the chip, improving the transmittance of the transparent conductive layer, and increasing the ESD capability of the chip. In addition, the current blocking protection layer group can protect the second-type semiconductor layer and block the current by arranging the blocking layer and the protective layer in different regions.

[0045] 2. Both the barrier layer and the protective layer are deposited by atomic layer deposition (ALD), which will not cause defects in the second-type semiconductor layer. A temporary barrier layer is added, and wet etching is used to remove the temporary barrier layer after the barrier layer is formed by atomic layer deposition and dry etching, so as to avoid defects in the second-type semiconductor layer when the barrier layer is formed by dry etching. Wet etching is used to remove the temporary barrier layer, which will not cause defects in the second-type semiconductor layer.

[0046] 3. The refractive index of the protective layer is greater than that of the transparent conductive layer, and less than that of the second-type semiconductor layer, which can play a role in enhancing transmittance and increase the light output of the LED chip.

[0047] 4. Since the SiO2 passivation layer is usually deposited by chemical vapor deposition, SiH4 is the gas used for the reaction during deposition. The H free radicals decomposed during the deposition process will reduce the ln2O3 in the transparent conductive layer ITO to In metal, affecting the transmittance of ITO and reducing the light efficiency of the LED chip. In addition, the surface of the passivation layer is too smooth and dense, which will limit the light extraction efficiency of the chip by reflection, reducing the light efficiency of the chip. A layer of microsphere anti-reflection coating that at least covers the exposed surface of the transparent conductive layer can, on the one hand, block the H free radicals from contacting the transparent conductive layer, and on the other hand, the surface of the microsphere anti-reflection coating is rough, which can increase the scattering effect, reduce reflection, increase the critical angle, allow more light to be refracted, and increase the light extraction efficiency of the LED chip.

[0048] 5. The microsphere anti-reflective coating contains at least two microspheres with different diameters, which can increase its surface roughness and increase the light extraction efficiency of the LED chip.

[0049] 6. The microsphere anti-reflective coating uses SiO2 microspheres, which are the same material as the passivation layer. When the microsphere anti-reflective coating and the passivation layer are patterned, they can be photolithographically processed together, which will not increase the photolithography cost and reduce the process steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0051] Figure 1 This is a schematic diagram of the structure of the LED chip in this application;

[0052] Figure 2 -10 is a structural schematic diagram of the LED chip manufacturing process in this application.

[0053] Reference numerals:

[0054] Substrate 1; first type semiconductor layer 2; active layer 3; second type semiconductor layer 4; current blocking protection layer group 5; blocking layer 51; protection layer 52; transparent conductive layer 6; microsphere anti-reflection coating 7; passivation layer 8; first electrode 9; second electrode 10; temporary blocking layer 20. DETAILED DESCRIPTION

[0055] To make the content of the present invention clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0056] In the following description, many specific details are set forth to facilitate a full understanding of the present application, but the present application may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0057] Secondly, the present application is described in detail with reference to the schematic diagram. When describing the embodiments of the present application in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present application. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0058] The present invention provides an LED chip, such as Figure 1 As shown, it includes a substrate 1, an epitaxial structure arranged on one side surface of the substrate 1, a first electrode 9 electrically connected to the first type semiconductor layer 2, and a second electrode 10 electrically connected to the second type semiconductor layer 4.

[0059] The epitaxial structure includes a first-type semiconductor layer 2, an active layer 3, a second-type semiconductor layer 4, a current blocking protection layer group 5 and a transparent conductive layer 6 arranged in sequence in a direction away from the substrate 1. Among them, one of the first-type semiconductor layer 2 and the second-type semiconductor layer 4 is a P-type semiconductor layer, and the other is an N-type semiconductor layer. This application is described by taking the first-type semiconductor layer 2 as an N-type semiconductor layer and the second-type semiconductor layer 4 as a P-type semiconductor layer as an example. Among them, the N-type semiconductor layer can be N-type GaN, and the P-type semiconductor layer can be P-type GaN.

[0060] like Figure 1 , 7 As shown, the second-type semiconductor layer 4 includes a first region facing the second electrode 10 and a remaining second region. The current blocking protection layer group 5 includes a blocking layer 51 and a protection layer 52; the blocking layer 51 is located in the first region; the protection layer 52 at least covers the second region and conducts the transparent conductive layer 6 and the second-type semiconductor layer 4.

[0061] The transparent conductive layer 6 is only stacked on the protective layer located in the second region, and the second electrode 10 is electrically connected to the second-type semiconductor layer 4 through the transparent conductive layer 6 and / or the protective layer.

[0062] The current blocking protective layer group 5 of the LED chip of the present application completely covers the second type semiconductor layer 4, isolates the second type semiconductor layer 4 and the transparent conductive layer 6, and avoids plasma bombardment on the second type semiconductor layer 4 to produce defects when the transparent conductive layer 6 is made by magnetron sputtering, thereby increasing the reliability of the chip, improving the transmittance of the transparent conductive layer, and increasing the ESD capability of the chip. In addition, the current blocking protective layer group 5 can protect the second type semiconductor layer 4 and block the current by setting the blocking layer 51 and the protective layer 52 in different regions.

[0063] Preferably, the thickness of the protective layer 52 is smaller than that of the barrier layer 51 , and the transparent conductive layer 6 only covers the protective layer 52 , thereby reducing the thickness of the LED chip increased due to protecting the second-type semiconductor layer 4 .

[0064] Furthermore, both the barrier layer 51 and the protective layer 52 are deposited by atomic layer deposition (ALD), and before depositing the barrier layer 51 and the protective layer 52, a temporary barrier layer 20 exposing the first region is deposited on the second type semiconductor layer 4 by chemical vapor deposition (CVD); and after the barrier layer 51 is formed by atomic layer deposition and dry etching, the temporary barrier layer 20 is removed by wet etching, and then the protective layer 52 is deposited. In the present application, the temporary barrier layer 20 includes but is not limited to SiO2, and its thickness can be set to 100nm-300nm, including the end value; the protective layer 52 covers the second region of the second type semiconductor layer 4 and the barrier layer 51.

[0065] Among them, the barrier layer 51 and the protective layer 52 are both deposited by atomic layer deposition (ALD), which will not cause defects in the second-type semiconductor layer 4. A temporary barrier layer 20 is added and wet etching is used to remove the temporary barrier layer 20 after the barrier layer 51 is formed by atomic layer deposition and dry etching, so as to avoid defects in the second-type semiconductor layer 4 when the barrier layer 51 is formed by dry etching. The temporary barrier layer 20 is removed by wet etching, which will not cause defects in the second-type semiconductor layer 4.

[0066] In a preferred embodiment, the material of the protection layer 52 is a conductive material or an insulating tunneling material.

[0067] The insulating tunneling material refers to an insulating material through which current can tunnel when a certain thickness is met. The thickness of the insulating tunneling layer is not greater than 5 nm. When the protective layer 52 is made of insulating tunneling material, the same material as the barrier layer 51 can be used.

[0068] For example, the barrier layer 51 includes but is not limited to Al2O3. The protective layer 52 can be made of Al2O3, HfO2, SnO2, AZO, ZrO2, etc.

[0069] Preferably, the thickness of the barrier layer 51 ranges from 50 nm to 200 nm, including the end points.

[0070] Among them, when the protection layer 52 is made of insulating tunneling material and the thickness is set to be no more than 5nm, it is to meet the current tunneling requirements. When the protection layer 52 is made of conductive material, the thickness range can be set to 5nm-10nm, including the end value.

[0071] For example, when the protective layer 52 is made of HfO2, Al2O3, or ZrO2, the thickness is not greater than 5 nm. When the protective layer 52 is made of SnO2 or AZO, the thickness can be set to a range of 5 nm to 10 nm.

[0072] In a preferred embodiment, the refractive index of the protective layer 52 is greater than the refractive index of the transparent conductive layer 6, and less than the refractive index of the second-type semiconductor layer 4. The refractive index of the protective layer 52 is greater than the refractive index of the transparent conductive layer 6, and less than the refractive index of the second-type semiconductor layer 4, which can play a role in enhancing transmittance and increase the light output of the LED chip. In the present application, the second-type semiconductor is P-GaN, and the transparent conductive layer is ITO, so the refractive index A of the protective layer 52 is in the range of 1.8<A<2.3. Among them, when the protective layer 52 is made of HfO2, SnO2, AZO, and ZrO2, its refractive index is greater than the refractive index of the transparent conductive layer 6, and less than the refractive index of the second-type semiconductor layer 4.

[0073] In a preferred embodiment, if Figure 1 As shown, the LED chip further includes a passivation layer 8 and a microsphere anti-reflection coating 7 stacked on the transparent conductive layer 6. The microsphere anti-reflection coating 7 covers at least the exposed surface of the transparent conductive layer 6. The passivation layer 8 is made of SiO2 material, which covers the exposed surface of the epitaxial structure, the first electrode 9, the second electrode 10 and the microsphere anti-reflection coating 7, and is provided with a through hole to expose the electrode. The transparent conductive layer 6 is ITO.

[0074] Since the SiO2 passivation layer 8 is made by chemical vapor deposition, the reaction gas during deposition will select SiH4. The H free radicals decomposed during the deposition process will reduce the ln2O3 in the transparent conductive layer 6 and ITO to In metal, affecting the transmittance of ITO and reducing the light efficiency of the LED chip. In addition, the surface of the passivation layer 8 is too smooth and dense, which will limit the light extraction efficiency of the chip by reflection, reducing the light efficiency of the chip. A layer of microsphere anti-reflection coating 7 that at least covers the exposed surface of the transparent conductive layer 6 can, on the one hand, block the H free radicals from contacting the transparent conductive layer 6. On the other hand, the surface of the microsphere anti-reflection coating 7 is a rough surface, which can increase the scattering effect, reduce reflection, increase the critical angle, allow more light to be refracted, and increase the light extraction efficiency of the LED chip.

[0075] Preferably, the microsphere anti-reflection coating 7 contains at least two microspheres with different diameters. Such an arrangement can increase its surface roughness and increase the light extraction efficiency of the LED chip.

[0076] Preferably, the microsphere anti-reflection coating 7 uses SiO2 microspheres, and the material of the microspheres is the same as that of the passivation layer 8. When the microsphere anti-reflection coating 7 and the passivation layer 8 are patterned, they can be photolithographically processed together, which does not increase the photolithography cost and reduces the process steps.

[0077] Specifically, Figure 1 As shown, the microsphere anti-reflection coating 7 of the present application also covers the exposed surfaces of the epitaxial structure, the first electrode 9 and the second electrode 10, and is provided with through holes exposing the electrodes. In this way, after the microsphere anti-reflection coating 7 and the passivation layer 8 are both manufactured, the through holes exposing the electrodes can be processed together. In this application, a horizontal structure LED chip in upright position is taken as an example, and the through holes exposing the first electrode 9 and the second electrode 10 need to be processed.

[0078] Preferably, the microsphere anti-reflective coating 7 includes SiO2 microspheres no larger than 2um, SiO2 microspheres no larger than 20nm, sodium dodecyl sulfate and anhydrous ethanol; wherein the volume ratio of SiO2 microspheres no larger than 2um: SiO2 microspheres no larger than 20nm: sodium dodecyl sulfate: anhydrous ethanol is 1:10:10:10.

[0079] The present application also provides a method for manufacturing an LED chip, such as Figure 2 -10, which includes the following steps:

[0080] S01: providing a substrate 1.

[0081] S02: growing an epitaxial structure on the surface of one side of the substrate 1; growing the epitaxial structure includes sequentially growing a first-type semiconductor layer 2, an active layer 3, a second-type semiconductor layer 4, a current blocking protection layer group 5 and a transparent conductive layer 6 in a direction away from the substrate 1.

[0082] S03: manufacturing a first electrode 9 electrically connected to the first-type semiconductor layer 2 .

[0083] S04: manufacturing a second electrode 10 electrically connected to the second-type semiconductor layer 4 .

[0084] like Figure 7 As shown, the second-type semiconductor layer 4 includes a first area facing the second electrode 10 and a remaining second area; the production of the current blocking protection layer group 5 includes producing a blocking layer 51 and a protective layer 52; the blocking layer 51 is located in the first area; the protective layer 52 at least covers the second area and conducts the transparent conductive layer 6 and the second-type semiconductor layer 4.

[0085] like Figure 8 As shown, the transparent conductive layer 6 is only stacked on the protective layer 52 in the second region, and the second electrode 10 is electrically connected to the second-type semiconductor layer 4 through the transparent conductive layer 6 and / or the protective layer 52 .

[0086] Among them, one of the first-type semiconductor layer 2 and the second-type semiconductor layer 4 is a P-type semiconductor layer, and the other is an N-type semiconductor layer. This application is described by taking the first-type semiconductor layer 2 as an N-type semiconductor layer and the second-type semiconductor layer 4 as a P-type semiconductor layer as an example. Among them, the N-type semiconductor layer can be N-type GaN, and the P-type semiconductor layer can be P-type GaN.

[0087] In step S02, after the first type semiconductor layer 2, the active layer 3 and the second type semiconductor layer 4 are grown on the substrate, a groove exposing the N type semiconductor layer is processed through photolithography and etching steps. The etching method is inductively coupled plasma etching, and the gases used for etching are: chlorine (Cl2), boron trichloride (BCl3), argon (Ar). The etching depth is 0.5um-4um, including the end value. After the groove processing is completed, the current blocking protection layer group 5 and the transparent conductive layer 6 are processed.

[0088] Preferably, the thickness of the protection layer 52 is smaller than the thickness of the barrier layer 51 .

[0089] Furthermore, in step S02, when manufacturing the current blocking protective layer group 5, the blocking layer 51 is manufactured first, and then the protective layer 52 is manufactured;

[0090] Before making the blocking layer 51, a temporary blocking material layer covering the second semiconductor layer 4 is deposited by chemical vapor deposition, and the temporary blocking material layer is photolithographically and wet-etched to form a temporary blocking layer 20 exposing the first area; the thickness of the temporary blocking layer 20 is 100nm-300nm.

[0091] A barrier material layer is formed on the temporary barrier layer 20 by atomic layer deposition, and the barrier material layer is subjected to photolithography and inductively coupled plasma ICP etching to form a barrier layer 51 covering the first region; specifically, as Figure 5 As shown, a photoresist layer covering only the first region is formed on the blocking material layer 20. Figure 6 As shown, the barrier layer 51 is further etched. Preferably, when the barrier material layer is etched by inductively coupled plasma ICP, the reaction gases are CF4 and O2, the reaction chamber pressure is 5-10 mTorr (including the endpoint value), and the RF power of the upper electrode and the lower electrode are 1000-1200 W (including the endpoint value) and 300-800 W (including the endpoint value) respectively.

[0092] like Figure 6 As shown, the semi-finished LED chip is placed in a BOE etching tank for wet etching to remove the temporary barrier layer 20 ; specifically, after removing the temporary barrier layer 20 , the photoresist layer on the barrier layer 51 also needs to be removed.

[0093] like Figure 7 As shown, a protective layer 52 covering at least the second region is deposited by atomic layer deposition. In the present application, the protective layer 52 covers the second region and the barrier layer 51.

[0094] When making the transparent conductive layer 6, a layer of transparent conductive layer material is first deposited on the protective layer 52 by magnetron sputtering, and then through lithography and etching are performed to make a through hole corresponding to the first area of ​​the second-type semiconductor layer 4, and the transparent conductive layer 6 is obtained after degumming.

[0095] Preferably, the material of the protection layer 52 is a conductive material or an insulating tunneling material.

[0096] The insulating tunneling material refers to an insulating material through which current can tunnel when a certain thickness is met.

[0097] Furthermore, the thickness of the insulating tunneling material is not greater than 5 nm. When the protective layer 52 is made of the insulating tunneling material, it can be made of the same material as the barrier layer 51 .

[0098] For example, the barrier layer 51 includes but is not limited to Al2O3. The protective layer 52 can be made of Al2O3, HfO2, SnO2, AZO, ZrO2, etc.

[0099] Preferably, the thickness of the barrier layer 51 ranges from 50 nm to 200 nm, including the end points.

[0100] When the protective layer 52 is made of insulating tunneling material and the thickness is set to be no greater than 5 nm, it is to meet the current tunneling requirements. When the protective layer 52 is made of conductive material, the thickness range can be set to 5 nm-10 nm, including the end value.

[0101] For example, when the protective layer 52 is made of HfO2, Al2O3, or ZrO2, the thickness is not greater than 5 nm. When the protective layer 52 is made of SnO2 or AZO, the thickness can be set to a range of 5 nm to 10 nm.

[0102] Preferably, the refractive index of the protective layer 52 is greater than the refractive index of the transparent conductive layer 6, and less than the refractive index of the second-type semiconductor layer 4. The refractive index of the protective layer 52 is greater than the refractive index of the transparent conductive layer 6, and less than the refractive index of the second-type semiconductor layer 4, which can play a role in enhancing transmittance and increase the light output of the LED chip. In the present application, when the second-type semiconductor is P-GaN and the transparent conductive layer is ITO, the refractive index A of the protective layer 52 is in the range of 1.8<A<2.3. Among them, when the protective layer 52 is made of HfO2, SnO2, AZO, and ZrO2, its refractive index is greater than the refractive index of the transparent conductive layer 6, and less than the refractive index of the second-type semiconductor layer 4.

[0103] Furthermore, if Fig. 9 As shown, the method for manufacturing an LED chip further includes manufacturing a microsphere anti-reflection coating 7 that at least covers the exposed surface of the transparent conductive layer 6. The transparent conductive layer 6 is ITO. After manufacturing the first electrode 9 and the second electrode 10, it also includes manufacturing a passivation layer 8; the passivation layer 8 is made of SiO2 material, which covers the exposed surface of the epitaxial structure, the first electrode 9, the second electrode 10 and the microsphere anti-reflection coating 7, and is provided with a through hole to expose the electrode.

[0104] Preferably, the microsphere anti-reflection coating 7 contains at least two kinds of microspheres with different diameters.

[0105] Preferably, the microsphere anti-reflection coating 7 is made of SiO2 microspheres. Fig. 9 As shown, the microsphere anti-reflection coating 7 of the present application also covers the exposed surfaces of the epitaxial structure, the first electrode 9 and the second electrode 10, and is provided with through holes exposing the electrodes. In this way, after the microsphere anti-reflection coating 7 and the passivation layer 8 are both manufactured, the through holes exposing the electrodes can be processed together. In this application, a horizontal structure LED chip mounted upright is taken as an example. Fig.10 As shown, it is necessary to process through holes to expose the first electrode 9 and the second electrode 10, forming Figure 1 The chip structure shown.

[0106] Preferably, the microsphere anti-reflective coating 7 includes SiO2 microspheres no larger than 2um, SiO2 microspheres no larger than 20nm, sodium dodecyl sulfate and anhydrous ethanol; wherein the volume ratio of SiO2 microspheres no larger than 2um: SiO2 microspheres no larger than 20nm: sodium dodecyl sulfate: anhydrous ethanol is 1:10:10:10.

[0107] Preferably, in steps S03 and S04, the first electrode 9 and the second electrode 10 are deposited by metal evaporation, and the thickness of the two electrodes is 0.5 um-8 um, including end values.

[0108] The manufacturing method of the LED chip of the present application corresponds to the above-mentioned LED chip, and has all the beneficial effects mentioned in the above-mentioned LED chip, which will not be repeated again. The parts not mentioned in the manufacturing method of the LED chip can be set with reference to the contents of the above-mentioned LED chip.

[0109] Those skilled in the art should understand that, in the disclosure of the present invention, the terms "horizontal", "vertical", "upper", "lower", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0110] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0111] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An LED chip, characterized in that: include: substrate; An epitaxial structure disposed on a surface of one side of the substrate; the epitaxial structure comprises a first-type semiconductor layer, an active layer, a second-type semiconductor layer, a current blocking protection layer group and a transparent conductive layer sequentially disposed in a direction away from the substrate; a first electrode electrically connected to the first-type semiconductor layer; a second electrode electrically connected to the second-type semiconductor layer; The second-type semiconductor layer includes a first region facing the second electrode and a remaining second region; the current blocking protection layer group includes a blocking layer and a protection layer; the blocking layer is located in the first region; the protection layer at least covers the second region and conducts between the transparent conductive layer and the second-type semiconductor layer; The transparent conductive layer is only stacked on the protective layer in the second region, and the second electrode is electrically connected to the second-type semiconductor layer through the transparent conductive layer and / or the protective layer.

2. The LED chip according to claim 1, characterized in that: The barrier layer and the protective layer are both deposited by atomic layer deposition (ALD), and before depositing the barrier layer and the protective layer, a temporary barrier layer is deposited on the second type semiconductor layer by chemical vapor deposition (CVD) to expose the first area; After the barrier layer is formed by atomic layer deposition and dry etching, wet etching is used to remove the temporary barrier layer, and then a protective layer is deposited.

3. The LED chip according to claim 1, characterized in that: The material of the protection layer is a conductive material or an insulating tunneling material.

4. The LED chip according to claim 3, characterized in that: The thickness of the insulating tunneling material is no more than 5 nm.

5. The LED chip according to claim 1, characterized in that: The refractive index of the protective layer is greater than the refractive index of the transparent conductive layer, and is less than the refractive index of the second-type semiconductor layer.

6. The LED chip according to claim 1, characterized in that: Also includes a passivation layer and a microsphere anti-reflection coating layer stacked on the transparent conductive layer; The microsphere anti-reflective coating at least covers the exposed surface of the transparent conductive layer; The transparent conductive layer is ITO; The passivation layer is made of SiO2 material, covers the exposed surfaces of the epitaxial structure, the first electrode, the second electrode and the microsphere anti-reflection coating, and is provided with through holes exposing the electrodes.

7. The LED chip according to claim 6, characterized in that: The microsphere anti-reflection coating contains at least two kinds of microspheres with different diameters.

8. The LED chip according to claim 6, characterized in that: The microsphere anti-reflection coating adopts SiO2 microspheres.

9. The LED chip according to claim 7, characterized in that: The microsphere anti-reflection coating includes SiO2 microspheres no larger than 2um, SiO2 microspheres no larger than 20nm, sodium dodecyl sulfate and anhydrous ethanol; wherein the volume ratio of SiO2 microspheres no larger than 2um: SiO2 microspheres no larger than 20nm: sodium dodecyl sulfate: anhydrous ethanol is 1:10:10:

10.

10. A method for manufacturing an LED chip, characterized in that: The following steps are involved: providing a substrate; Growing an epitaxial structure on the surface of one side of the substrate; growing the epitaxial structure includes sequentially growing a first-type semiconductor layer, an active layer, a second-type semiconductor layer, a current blocking protection layer group and a transparent conductive layer in a direction away from the substrate; Making a first electrode electrically connected to the first-type semiconductor layer; Making a second electrode electrically connected to the second-type semiconductor layer; The second-type semiconductor layer includes a first region facing the second electrode and a remaining second region; manufacturing the current blocking protection layer group includes manufacturing a blocking layer and a protection layer; the blocking layer is located in the first region; the protection layer at least covers the second region and conducts the transparent conductive layer and the second-type semiconductor layer; The transparent conductive layer is only stacked on the protective layer in the second region, and the second electrode is electrically connected to the second-type semiconductor layer through the transparent conductive layer and / or the protective layer.

11. A method for manufacturing an LED chip according to claim 10, characterized in that: When manufacturing the current blocking protective layer group, the blocking layer is manufactured first, and then the protective layer is manufactured; Before making the barrier layer, the method further includes depositing a temporary barrier material layer covering the second-type semiconductor layer by chemical vapor deposition, and performing photolithography and wet etching on the temporary barrier material layer to form a temporary barrier layer exposing the first area; Forming a barrier material layer on the temporary barrier layer by atomic layer deposition, and performing photolithography and inductively coupled plasma (ICP) etching on the barrier material layer to form a barrier layer covering the first region; Placing the semi-finished LED chip in a BOE etching tank for wet etching to remove the temporary barrier layer; A protective layer covering at least the second region is deposited by atomic layer deposition.

12. The method for manufacturing an LED chip according to claim 10, characterized in that: The material of the protection layer is a conductive material or an insulating tunneling material.

13. The LED chip according to claim 10, characterized in that: The refractive index of the protective layer is greater than the refractive index of the transparent conductive layer, and is less than the refractive index of the second-type semiconductor layer.

14. The LED chip according to claim 10, characterized in that: It also includes making a microsphere anti-reflective coating covering at least the exposed surface of the transparent conductive layer; The transparent conductive layer is ITO; After the first electrode and the second electrode are manufactured, a passivation layer is manufactured; the passivation layer is made of SiO2 material, covers the exposed surfaces of the epitaxial structure, the first electrode, the second electrode and the microsphere anti-reflection coating, and is provided with through holes to expose the electrodes.

15. The LED chip according to claim 14, characterized in that: The microsphere anti-reflection coating contains at least two kinds of microspheres with different diameters.

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