LED chip, preparation method thereof, and lighting equipment

Abstract

The present invention provides an LED chip, a preparation method thereof, and a lighting device, and relates to the field of semiconductor technology. The electrode pad and the electrode finger are both composed of two film layers, a reflective electrode layer and an electrode layer. The first reflective electrode layer can improve the light reflectivity at the electrode finger, and the second reflective electrode layer can improve the light reflectivity at the electrode pad, thereby achieving the purpose of improving the luminous efficiency of the LED chip. The first electrode layer and the second electrode layer can be understood as the electrode layers of a conventional LED chip. The first electrode layer covers the first reflective electrode layer, and the second electrode layer covers the second reflective electrode layer, which can prevent the reflective electrode layer from peeling off from the epitaxial layer; and the second electrode layer also contacts the protruding structure of the epitaxial layer itself. The contact stability of this part is relatively higher than the contact stability between the second electrode layer and the second reflective electrode layer, which can prevent peeling between the second electrode layer and the second reflective electrode layer, thereby comprehensively improving the stability of the electrode structure.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to an LED chip, a preparation method thereof, and a lighting device. Background Art

[0002] With the gradual development of LEDs (Light Emitting Diodes), LED lighting has completely replaced traditional lighting sources. Keeping pace with technological innovation and the continuous advancement of intelligent manufacturing towards scale, automation, and digitalization, the current LED market is extremely competitive, and LED chip manufacturers are pursuing LED chips with higher luminous efficiency.

[0003] In some current existing technologies, the electrode pads of LED chips use highly reflective electrodes such as Al, Ag or DBR to increase the light reflectivity of the electrode pad area, thereby improving the luminous efficiency of the LED chip.

[0004] However, the electrode pads in the form of highly reflective electrodes such as Al, Ag or DBR structures have poor fixing effects on the epitaxial layer, and it is easy for the electrode pads to peel off, affecting the structural stability of the LED chip. Summary of the Invention

[0005] In view of the above problems, the present application provides an LED chip and its preparation method, as well as a lighting device, which improves the luminous efficiency of the LED chip and prevents the electrode pad from peeling off. The specific solution is as follows:

[0006] In a first aspect, the present application provides an LED chip, comprising:

[0007] substrate;

[0008] an epitaxial layer located on one side of the substrate, the epitaxial layer comprising an N-type semiconductor layer, a multi-quantum well layer, and a P-type semiconductor layer stacked in sequence in a first direction; the first direction is perpendicular to the plane of the substrate and points from the substrate to the epitaxial layer;

[0009] an electrode structure comprising an N-electrode pad electrically connected to the N-type semiconductor layer and a P-electrode pad electrically connected to the P-type semiconductor layer; at least one of the N-electrode pad and the P-electrode pad further comprising an electrode finger extending outward from the electrode pad;

[0010] The epitaxial layer has a patterned film layer for setting the electrode structure, and the patterned film layer includes an electrode pad patterned area and an electrode finger patterned area;

[0011] The electrode finger is located in the electrode finger patterned area, and the electrode finger includes a first reflective electrode layer and a first electrode layer stacked in the first direction, and the first electrode layer at least completely covers the first reflective electrode layer;

[0012] The electrode pad patterned area has a convex structure, and the convex structure and the patterned film layer are an integrated structure;

[0013] The electrode pad is located in the electrode pad patterned area, and the electrode pad includes a second reflective electrode layer and a second electrode layer; in the first direction, the thickness of the second reflective electrode layer is less than or equal to the height of the protruding structure, and the second electrode layer at least completely covers the second reflective electrode layer.

[0014] Preferably, in the above LED chip, the first electrode layer and the second electrode layer are an integrally formed electrode layer.

[0015] Preferably, in the above-mentioned LED chip, the first reflective electrode layer is a combination of one or more of an Al material layer, an Ag material layer and a DBR layer, and / or the second reflective electrode layer is a combination of one or more of an Al material layer, an Ag material layer and a DBR layer.

[0016] Preferably, in the above LED chip, the material of the first electrode layer is Cr material or Ni material, and / or the material of the second electrode layer is Cr material or Ni material.

[0017] Preferably, in the above LED chip, the thickness of the first reflective electrode layer is in the range of 0.2 μm-0.5 μm, inclusive, and / or the thickness of the second reflective electrode layer is in the range of 0.2 μm-0.5 μm, inclusive.

[0018] A second aspect of the present application provides a method for preparing an LED chip, the method comprising:

[0019] providing a substrate;

[0020] forming an epitaxial layer on one side of the substrate, the epitaxial layer comprising an N-type semiconductor layer, a multi-quantum well layer, and a P-type semiconductor layer stacked in sequence in a first direction; the first direction being perpendicular to the plane of the substrate and pointing from the substrate to the epitaxial layer;

[0021] Processing the epitaxial layer so that the epitaxial layer has a patterned film layer for arranging the electrode structure, wherein the patterned film layer includes an electrode pad patterned region and an electrode finger patterned region; the electrode pad patterned region has a protruding structure, and the protruding structure and the patterned film layer are an integrated structure;

[0022] An electrode structure is prepared, the electrode structure including an N-electrode pad electrically connected to the N-type semiconductor layer, and a P-electrode pad electrically connected to the P-type semiconductor layer; at least one of the N-electrode pad and the P-electrode pad further includes an electrode finger extending outward from the electrode pad; the electrode finger is located in the electrode finger patterned area, the electrode finger includes a first reflective electrode layer and a first electrode layer stacked in the first direction, the first electrode layer at least completely covering the first reflective electrode layer; the electrode pad is located in the electrode pad patterned area, the electrode pad includes a second reflective electrode layer and a second electrode layer; in the first direction, the thickness of the second reflective electrode layer is less than or equal to the height of the protruding structure, and the second electrode layer at least completely covers the second reflective electrode layer.

[0023] Preferably, in the above-mentioned method for preparing the LED chip, the first electrode layer and the second electrode layer are an integrally formed electrode layer, and the preparation of the electrode structure includes:

[0024] A film evaporation is performed once to form an electrode layer, wherein the electrode layer at least completely covers the first reflective electrode layer and at least completely covers the second reflective electrode layer.

[0025] Preferably, in the above-mentioned method for preparing the LED chip, when the material of the reflective electrode layer is Al material and is in contact with the GaN layer, before forming the reflective electrode layer, the method for preparing the LED chip further comprises:

[0026] SiCl4 ion implantation is performed on a target region of the GaN layer to adjust the surface doping content of the target region; the target region is a contact region between the GaN layer and the reflective electrode layer.

[0027] Preferably, in the above-mentioned method for preparing an LED chip, when the reflective electrode layer is made of Al and is in contact with the ITO layer, after forming the reflective electrode layer, the method for preparing an LED chip further comprises:

[0028] The reflective electrode layer is subjected to high-temperature alloy treatment.

[0029] A third aspect of the present application provides a lighting device, comprising any one of the above-mentioned LED chips.

[0030] By means of the above technical solution, the present application provides an LED chip and its preparation method, and lighting equipment. The electrode pads and electrode fingers are both composed of two film layers, a reflective electrode layer and an electrode layer. The first reflective electrode layer can improve the light reflectivity at the electrode fingers, and the second reflective electrode layer can improve the light reflectivity at the electrode pads, thereby achieving the purpose of improving the luminous efficiency of the LED chip. The first electrode layer and the second electrode layer can be understood as the electrode layers of a conventional LED chip. By covering the first reflective electrode layer with the first electrode layer and the second reflective electrode layer with the second electrode layer, peeling of the reflective electrode layer and the epitaxial layer can be avoided. The second electrode layer also contacts the raised structure of the epitaxial layer itself, which is equivalent to the contact method between the electrode layer and the epitaxial layer of a conventional LED chip. The contact stability of this part is relatively higher than the contact stability between the second electrode layer and the second reflective electrode layer, which can avoid peeling between the second electrode layer and the second reflective electrode layer, thereby comprehensively improving the stability of the electrode structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and other features, advantages, and aspects of the various embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. Throughout the drawings, the same or similar reference numerals represent the same or similar elements. It should be understood that the drawings are schematic and that the originals and elements are not necessarily drawn to scale.

[0032] Figure 1 A schematic diagram of a partial structure of an LED chip provided by an embodiment of the present invention;

[0033] Figure 2 A schematic diagram of a partial structure of another LED chip provided by an embodiment of the present invention;

[0034] Figure 3 A schematic diagram of a partial structure of another LED chip provided by an embodiment of the present invention;

[0035] Figure 4 A schematic diagram of a partial structure of another LED chip provided by an embodiment of the present invention;

[0036] Figure 5 A schematic diagram of a top view of an LED chip provided by an embodiment of the present invention;

[0037] Figure 6 A schematic flow chart of a method for preparing an LED chip provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application. The terms used in the implementation methods of the present application are only used to explain the specific embodiments of the present application and are not intended to limit the present application. It is known to those skilled in the art that with the development of technology and the emergence of new scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems. It should be noted that the directional words appearing in the present invention are based on the relative position relationship shown in the drawings and cannot be used as absolute limitations on the present application.

[0039] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0040] refer to Figure 1 , Figure 1 FIG1 is a partial structural diagram of an LED chip provided by an embodiment of the present invention. The LED chip provided by an embodiment of the present invention includes: a substrate 11.

[0041] The epitaxial layer located on one side of the substrate 11 includes an N-type semiconductor layer 12, a multi-quantum well layer 13 and a P-type semiconductor layer 14 stacked in sequence in a first direction; the first direction is perpendicular to the plane of the substrate 11 and points from the substrate 11 to the epitaxial layer.

[0042] An electrode structure includes an N-electrode pad 15 electrically connected to the N-type semiconductor layer 12 and a P-electrode pad 16 electrically connected to the P-type semiconductor layer 14 .

[0043] It should be noted that in Figure 1 In the description, only the contact between the N-electrode pad 15 and the N-type semiconductor layer 12 is used as an example, and the contact between the P-electrode pad 16 and the P-type semiconductor layer 14 is used as an example. The N-electrode pad 15 can obviously be electrically connected to the N-type semiconductor layer 12 through some other functional film layers, and the P-electrode pad 16 can obviously be electrically connected to the P-type semiconductor layer 14 through some other functional film layers. In other words, as long as the N-electrode pad 15 is electrically connected to the N-type semiconductor layer 12, the relative positional relationship between the two is not strictly limited; similarly, as long as the P-electrode pad 16 is electrically connected to the P-type semiconductor layer 14, the relative positional relationship between the two is not strictly limited.

[0044] refer to Figure 2 , Figure 2 A schematic diagram of a partial structure of another LED chip provided by an embodiment of the present invention, referring to Figure 3 , Figure 3 A schematic diagram of a partial structure of another LED chip provided by an embodiment of the present invention, referring to Figure 4 , Figure 4This is a partial structural diagram of another LED chip provided by an embodiment of the present invention. In the LED chip provided by an embodiment of the present invention, at least one of the N-electrode pad 15 and the P-electrode pad 16 further includes electrode fingers extending outward from the electrode pad.

[0045] like Figure 2 and Figure 4 As shown, the N-electrode pad 15 has an N-electrode finger 151 extending outward from the N-electrode pad 15, and the P-electrode pad 16 has a P-electrode finger 161 extending outward from the P-electrode pad 16. Figure 2 The electrode fingers shown are in the form of discontinuous electrode fingers. Figure 4 The electrode fingers shown are in the form of continuous electrode fingers.

[0046] like Figure 3 As shown, the P-electrode pad 16 has a P-electrode finger 161 extending outward from the P-electrode pad 16 , while the N-electrode pad 15 does not have an N-electrode finger extending outward from the N-electrode pad 15 .

[0047] However, no matter which form is adopted, the N-electrode pad 15 and the P-electrode pad 16 are necessary structures to realize the electrical connection between the LED chip and the outside.

[0048] It should be noted that the technical solution of the present application can improve any one of the four parts, namely, the N-electrode pad 15, the N-electrode finger 151 corresponding to the N-electrode pad 15, the P-electrode pad 16, and the P-electrode finger 161 corresponding to the P-electrode pad 16, or improve at least two of the above parts.

[0049] In the LED chip provided by the embodiments of the present invention, the epitaxial layer includes a patterned film layer for providing the electrode structure. The patterned film layer includes a patterned electrode pad region and a patterned electrode finger region. For a P-electrode structure, the patterned film layer can be a P-type semiconductor layer 14, a transparent conductive layer (also known as an ITO layer), or other functional film layer. For an N-electrode structure, the patterned film layer can be an N-type semiconductor layer 12, a transparent conductive layer (also known as an ITO layer), or other functional film layer.

[0050] The electrode finger is located in the electrode finger patterned area. The electrode finger includes a first reflective electrode layer and a first electrode layer stacked in the first direction. The first electrode layer at least completely covers the first reflective electrode layer.

[0051] The electrode pad patterned area has a protruding structure 17, and the protruding structure 17 and the patterned film layer are an integral structure; the electrode pad is located in the electrode pad patterned area, and the electrode pad includes a second reflective electrode layer and a second electrode layer; in the first direction, the thickness of the second reflective electrode layer is less than or equal to the height of the protruding structure 17, and the second electrode layer at least completely covers the second reflective electrode layer.

[0052] like Figure 2-Figure 4 As shown, the shape of the protrusion structure 17 can be a column or a ring or other shapes, and the arrangement can also be Figure 4 The array arrangement shown is not limited in the embodiment of the present invention.

[0053] In the first direction, the thickness of the second reflective electrode layer is less than or equal to the height of the protruding structure 17 to ensure that the second electrode layer can directly contact the protruding structure 17 and avoid the second reflective layer completely covering the protruding structure 17. Ultimately, the second electrode layer can partially contact the protruding structure 17 and partially contact the second reflective layer.

[0054] Specifically, in embodiments of the present invention, the first reflective electrode layer can improve the light reflectivity at the electrode fingers, and the second reflective electrode layer can improve the light reflectivity at the electrode pads, thereby achieving the purpose of improving the luminous efficiency of the LED chip. The first electrode layer and the second electrode layer can be understood as the electrode layers of a conventional LED chip. With the first electrode layer covering the first reflective electrode layer and the second electrode layer covering the second reflective electrode layer, peeling between the reflective electrode layer and the epitaxial layer can be prevented. The second electrode layer also contacts the raised structure of the epitaxial layer itself, which is equivalent to the contact between the electrode layer and the film layer of the epitaxial layer in a conventional LED chip. The contact stability of this part is relatively higher than the contact stability between the second electrode layer and the second reflective electrode layer, which can prevent peeling between the second electrode layer and the second reflective electrode layer. In other words, the contact stability between the second electrode layer and the second reflective electrode layer is further improved, thereby comprehensively improving the stability of the electrode structure.

[0055] In another embodiment of the present invention, the first reflective electrode layer is a combination of one or more of an Al material layer, an Ag material layer and a DBR layer, and / or the second reflective electrode layer is a combination of one or more of an Al material layer, an Ag material layer and a DBR layer.

[0056] The material of the first electrode layer is Cr material or Ni material or other electrode materials of conventional LED chips, and / or the material of the second electrode layer is Cr material or Ni material or other electrode materials of conventional LED chips.

[0057] The thickness of the first reflective electrode layer is in a range of 0.2 μm to 0.5 μm, inclusive; and / or the thickness of the second reflective electrode layer is in a range of 0.2 μm to 0.5 μm, inclusive.

[0058] Specifically, in the embodiment of the present invention, the film layers to which the LED chip is finally welded to the welding wire are the first electrode layer and the second electrode layer. The first electrode layer and the second electrode layer are made of Cr material or Ni material, that is, conventional LED chip electrode materials are used as the materials of the first electrode layer and the second electrode layer. The eutectic ability with the welding wire is good, which avoids the abnormality of loose welding wire and falling off of solder balls, thereby improving the welding wire effect of the LED chip.

[0059] It should be noted that the material of the first reflective electrode layer and the material of the second reflective electrode layer can be the same or different, and is not limited in the embodiments of the present application; the material of the first electrode layer and the material of the second electrode layer can be the same or different, and is not limited in the embodiments of the present application; the thickness of the first reflective electrode layer and the thickness of the second reflective electrode layer can be the same or different, and is not limited in the embodiments of the present application.

[0060] In another embodiment of the present invention, referring to Figure 5 , Figure 5 This is a schematic diagram of a top view of an LED chip provided by an embodiment of the present invention, wherein the first electrode layer and the second electrode layer are an integrally formed electrode layer.

[0061] Specifically, in the embodiment of the present invention, the entire surface of the first electrode layer and the second electrode layer can be prepared through one process, thereby simplifying the preparation method of the LED chip and reducing the manufacturing cost.

[0062] For example, when the N-electrode pad 15 and the N-electrode finger 151 corresponding to the N-electrode pad 15 are improved, the first electrode layer corresponding to the N-electrode finger 151 and the second electrode layer corresponding to the N-electrode pad 15 are an integrally formed electrode layer, that is, the preparation of the entire film layer of the first electrode layer and the second electrode layer is achieved through one process.

[0063] Similarly, when the P-electrode pad 16 and the P-electrode finger 161 corresponding to the P-electrode pad 16 are improved, the first electrode layer corresponding to the P-electrode finger 161 and the second electrode layer corresponding to the P-electrode pad 16 are an integrally formed electrode layer, that is, the preparation of the entire film layer of the first electrode layer and the second electrode layer is achieved through one process.

[0064] Based on the above embodiment of the invention, another embodiment of the present invention further provides a method for preparing an LED chip, referring to Figure 6 , Figure 6A schematic flow chart of a method for preparing an LED chip according to an embodiment of the present invention. The method for preparing an LED chip according to an embodiment of the present invention comprises:

[0065] S101: Provide a substrate 11.

[0066] S102: Forming an epitaxial layer on one side of the substrate, the epitaxial layer including an N-type semiconductor layer 12, a multi-quantum well layer 13, and a P-type semiconductor layer 14 stacked in sequence in a first direction; the first direction is perpendicular to the plane of the substrate 11 and points from the substrate 11 to the epitaxial layer.

[0067] S103: Processing the epitaxial layer so that the epitaxial layer has a patterned film layer for setting the electrode structure, the patterned film layer includes an electrode pad patterned area and an electrode finger patterned area; the electrode pad patterned area has a protruding structure 17, and the protruding structure 17 and the patterned film layer are an integrated structure.

[0068] Specifically, the steps for processing the epitaxial layer include but are not limited to the following steps:

[0069] In an optional embodiment of the present invention, the method for preparing an LED chip may further include: cleaning the above-mentioned epitaxial layer, including but not limited to preparing a mesa photolithography pattern through processes such as coating, exposure, and development, including but not limited to etching a mesa area through an ICP process, and then removing the photoresist.

[0070] In an optional embodiment of the present invention, the method for preparing the LED chip may further include: depositing a SiO2 barrier layer with a thickness ranging from 2100 angstroms to 4100 angstroms (including end points) on the surface of the above-mentioned source chip, including but not limited to using a PECVD machine.

[0071] In an optional embodiment of the present invention, the method for preparing an LED chip may further include: preparing a CB (also known as a current blocking layer in the field) photolithography pattern on the surface of the above-mentioned source through processes such as coating, exposure, and development, including but not limited to etching through a BOE process, and then removing the photoresist.

[0072] In an optional embodiment of the present invention, the method for preparing the LED chip may also include: including but not limited to depositing a transparent conductive layer (also known as ITO layer in the field) with a thickness ranging from 600 angstroms to 1100 angstroms (including end points) on the surface of the above-mentioned source through a sputtering process.

[0073] In an optional embodiment of the present invention, the method for preparing the LED chip may further include: annealing the transparent conductive layer in a rapid annealing furnace, the annealing temperature range may be 500°C-650°C (including endpoint values), and the annealing time range may be 1min-10min (including endpoint values).

[0074] In an optional embodiment of the present invention, the method for preparing the LED chip may further include: including but not limited to using a conformal photoresist as a mask, wet etching the transparent conductive layer, and removing the photoresist after etching.

[0075] It should be noted that, based on the P-electrode structure, the patterned film layer can be a P-type semiconductor layer 14 or a transparent conductive layer (also known as an ITO layer), or other functional film layer; based on the N-electrode structure, the patterned film layer can be an N-type semiconductor layer 12 or a transparent conductive layer (also known as an ITO layer), or other functional film layer. This is not limited in the embodiments of the present application.

[0076] S104: Prepare an electrode structure, wherein the electrode structure includes an N-electrode pad 15 electrically connected to the N-type semiconductor layer 12, and a P-electrode pad 16 electrically connected to the P-type semiconductor layer 14; at least one of the N-electrode pad 15 and the P-electrode pad 16 further includes an electrode finger extending outward based on the electrode pad; the electrode finger is located in the electrode finger patterned area, and the electrode finger includes a first reflective electrode layer and a first electrode layer stacked in the first direction, and the first electrode layer at least completely covers the first reflective electrode layer; the electrode pad is located in the electrode pad patterned area, and the electrode pad includes a second reflective electrode layer and a second electrode layer; in the first direction, the thickness of the second reflective electrode layer is less than or equal to the height of the protruding structure 17, and the second electrode layer at least completely covers the second reflective electrode layer.

[0077] Specifically, in the embodiments of the present invention, including but not limited to using a negative photoresist as a mask, including but not limited to performing a first metal evaporation by electron beam evaporation to form a reflective electrode layer, and performing metal stripping and photoresist removal after evaporation to form an Al material layer, an Ag material layer or a DBR layer. The reflective electrode layer can have a thickness ranging from 0.2 μm to 0.5 μm, including the end values.

[0078] Including but not limited to using a negative photoresist as a mask, including but not limited to performing a second metal evaporation by electron beam evaporation to form an electrode layer, performing metal stripping and photoresist removal after evaporation, forming an electrode layer of Cr material or Ni material or other conventional LED chip electrode material, the thickness of which can range from 1.3μm to 2.1μm, including end points.

[0079] It should be noted that when forming the electrode layer, the first electrode layer and the second electrode layer can be formed in steps, or the preparation of the entire film layer of the first electrode layer and the second electrode layer can be achieved in one process, thereby simplifying the preparation method of the LED chip and reducing the manufacturing cost.

[0080] In an optional embodiment of the present invention, when the reflective electrode layer is made of Al and is in contact with the GaN layer, before forming the reflective electrode layer, the method for preparing the LED chip further includes:

[0081] SiCl4 ion implantation is performed on a target region of the GaN layer to adjust the surface doping content of the target region; the target region is a contact region between the GaN layer and the reflective electrode layer.

[0082] Specifically, by changing the surface doping content of the target area of ​​the GaN layer, the problem of poor ohmic contact between the reflective electrode layer of the Al material and the GaN layer is solved, thereby further improving the photoelectric performance of the LED chip.

[0083] In an optional embodiment of the present invention, when the reflective electrode layer is made of Al and is in contact with the ITO layer, after forming the reflective electrode layer, the method for preparing the LED chip further includes:

[0084] The reflective electrode layer is subjected to high-temperature alloy treatment.

[0085] Specifically, by subjecting the reflective electrode layer to high-temperature alloy treatment, the problem of poor adhesion between the reflective electrode layer made of Al and the ITO layer in direct contact can be solved, thereby improving the contact stability between the reflective electrode layer made of Al and the ITO layer.

[0086] In an optional embodiment of the present invention, the method for preparing the LED chip may further include: including but not limited to using a PECVD process to deposit a SiO2 insulating layer with a thickness ranging from 2300 angstroms to 10000 angstroms (including end points) on the surface of the above-mentioned source.

[0087] In an optional embodiment of the present invention, the method for preparing the LED chip may further include: including but not limited to using a positive photoresist as a mask, wet etching the insulating layer, and removing the photoresist after etching.

[0088] In an optional embodiment of the present invention, the method for preparing an LED chip may further include: performing electrical sampling on the prepared wafer based on COW.

[0089] In an optional embodiment of the present invention, the method for preparing the LED chip may further include: grinding to thin the wafer to a fixed thickness, for example, thinning it to 100μm-120μm (including the endpoint values), and evaporating a DBR structure with a thickness of approximately 3μm-5μm (including the endpoint values) on the back.

[0090] In an optional embodiment of the present invention, the method for preparing an LED chip may further include: cutting the wafer to obtain an LED chip with a single core particle.

[0091] Based on the above embodiment of the present invention, another embodiment of the present invention provides a lighting device, which includes the LED chip described in the above embodiment.

[0092] The above is a detailed introduction to an LED chip, a preparation method thereof, and a lighting device provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

[0093] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.

[0094] It should also be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that the process, method, article, or apparatus comprising a series of elements inherent to the elements, or also including elements inherent to these processes, methods, articles, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element.

[0095] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily 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 is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An LED chip, characterized in that: The LED chip includes: substrate; an epitaxial layer located on one side of the substrate, the epitaxial layer comprising an N-type semiconductor layer, a multi-quantum well layer, and a P-type semiconductor layer stacked in sequence in a first direction; the first direction is perpendicular to the plane of the substrate and points from the substrate to the epitaxial layer; an electrode structure comprising an N-electrode pad electrically connected to the N-type semiconductor layer and a P-electrode pad electrically connected to the P-type semiconductor layer; at least one of the N-electrode pad and the P-electrode pad further comprising an electrode finger extending outward from the electrode pad; The epitaxial layer has a patterned film layer for setting the electrode structure, and the patterned film layer includes an electrode pad patterned area and an electrode finger patterned area; The electrode finger is located in the electrode finger patterned area, and the electrode finger includes a first reflective electrode layer and a first electrode layer stacked in the first direction, and the first electrode layer at least completely covers the first reflective electrode layer; The electrode pad patterned area has a protruding structure, and the protruding structure and the patterned film layer are an integrated structure; the protruding structure is in the shape of a column or a ring; The N-electrode pad and the P-electrode pad are both located in the electrode pad patterned area, and the N-electrode pad and the P-electrode pad both include a second reflective electrode layer and a second electrode layer; in the first direction, the thickness of the second reflective electrode layer is less than or equal to the height of the protruding structure, and the second electrode layer at least completely covers the second reflective electrode layer.

2. The LED chip according to claim 1, wherein: The first electrode layer and the second electrode layer are an integrally formed electrode layer.

3. The LED chip according to claim 1, wherein: The first reflective electrode layer is a combination of one or more of an Al material layer, an Ag material layer and a DBR layer, and / or the second reflective electrode layer is a combination of one or more of an Al material layer, an Ag material layer and a DBR layer.

4. The LED chip according to claim 1, wherein The material of the first electrode layer is Cr material or Ni material, and / or the material of the second electrode layer is Cr material or Ni material.

5. The LED chip according to claim 1, wherein: The thickness of the first reflective electrode layer is in a range of 0.2 μm to 0.5 μm, inclusive, and / or the thickness of the second reflective electrode layer is in a range of 0.2 μm to 0.5 μm, inclusive.

6. A method for preparing an LED chip, characterized in that: The method for preparing the LED chip comprises: providing a substrate; forming an epitaxial layer on one side of the substrate, the epitaxial layer comprising an N-type semiconductor layer, a multi-quantum well layer, and a P-type semiconductor layer stacked in sequence in a first direction; the first direction being perpendicular to the plane of the substrate and pointing from the substrate to the epitaxial layer; The epitaxial layer is processed so that the epitaxial layer has a patterned film layer for arranging an electrode structure, the patterned film layer includes an electrode pad patterned region and an electrode finger patterned region; the electrode pad patterned region has a protruding structure, the protruding structure and the patterned film layer are an integral structure; the protruding structure is in the shape of a column or a ring; An electrode structure is prepared, the electrode structure including an N-electrode pad electrically connected to the N-type semiconductor layer, and a P-electrode pad electrically connected to the P-type semiconductor layer; at least one of the N-electrode pad and the P-electrode pad further includes an electrode finger extending outward from the electrode pad; the electrode finger is located in the electrode finger patterned area, the electrode finger includes a first reflective electrode layer and a first electrode layer stacked in the first direction, the first electrode layer at least completely covering the first reflective electrode layer; the N-electrode pad and the P-electrode pad are both located in the electrode pad patterned area, the N-electrode pad and the P-electrode pad each include a second reflective electrode layer and a second electrode layer; in the first direction, the thickness of the second reflective electrode layer is less than or equal to the height of the protruding structure, and the second electrode layer at least completely covers the second reflective electrode layer.

7. The method for preparing an LED chip according to claim 6, wherein: The first electrode layer and the second electrode layer are an integrally formed electrode layer, and the preparation of the electrode structure includes: A film evaporation is performed once to form an electrode layer, wherein the electrode layer at least completely covers the first reflective electrode layer and at least completely covers the second reflective electrode layer.

8. The method for preparing an LED chip according to claim 6, wherein: When the reflective electrode layer is made of Al and is in contact with the GaN layer, before forming the reflective electrode layer, the method for preparing the LED chip further includes: SiCl4 ion implantation is performed on a target region of the GaN layer to adjust the surface doping content of the target region; the target region is a contact region between the GaN layer and the reflective electrode layer.

9. The method for preparing an LED chip according to claim 6, wherein: When the reflective electrode layer is made of Al and contacts the ITO layer, after forming the reflective electrode layer, the method for preparing the LED chip further includes: The reflective electrode layer is subjected to high-temperature alloy treatment.

10. A lighting device, characterized in that: The lighting device comprises the LED chip according to any one of claims 1 to 5.

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