Light emitting diode, product and manufacturing method therefor

Abstract

Provided are an LED, a product and a manufacturing method therefor, belonging to the technical field of photoelectrons. The LED comprises a substrate, a first light-emitting unit, a second light-emitting unit, an insulating layer and a transparent conductive layer; the first light-emitting unit and the second light-emitting unit are spaced apart and each comprises a first semiconductor layer, a multi-quantum well layer and a second semiconductor layer which are sequentially stacked, a groove exposing a first semiconductor layer is provided in each second semiconductor layer; the insulating layer covers the first light-emitting unit and the second light-emitting unit and is located on the surface of the substrate, and the insulating layer is provided with first through holes respectively exposing the second semiconductor layers of the first light-emitting unit and the second light-emitting unit, and second through holes respectively exposing the grooves of the first light-emitting unit and the second light-emitting unit; the transparent conductive layer is located on the second semiconductor layers of the first light-emitting unit and the second light-emitting unit and is separately connected to the corresponding second semiconductor layers via the first through holes, and the first semiconductor layer of the first light-emitting unit is electrically connected to the second semiconductor layer of the second light-emitting unit.

Description

Light-emitting diode, product and preparation method thereof

[0001] This application claims priority to Chinese patent application No. 202311101498.6, filed on August 29, 2023, entitled “Light Emitting Diode Devices and Articles,” the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present disclosure relates to the field of optoelectronic manufacturing technology, and in particular to a light emitting diode, a product and a preparation method thereof. Background Art

[0003] Light Emitting Diodes (LEDs) are common light-emitting devices. LEDs are typically manufactured by fabricating various film layers on a substrate and performing patterning, then cutting the substrate to form individual LED cores.

[0004] Summary of the Invention

[0005] The embodiments of the present disclosure provide an LED, a product, and a method for manufacturing the same.

[0006] On the one hand, an embodiment of the present disclosure provides a product, which includes a substrate and a plurality of LED devices located on the substrate, each of the LED devices including an epitaxial layer, an insulating layer and a transparent conductive layer stacked in sequence on the substrate, the insulating layer having a first through hole exposing the epitaxial layer, and the transparent conductive layer being connected to the epitaxial layer through the first through hole; the substrate having a central area and an annular area, the annular area surrounding the central area, and a plurality of the LED devices being arranged in both the central area and the annular area; the area of ​​the contact surface between the first through hole of the LED device in the central area and the epitaxial layer is larger than the area of ​​the contact surface between the first through hole of the LED device in the annular area and the epitaxial layer, and the thickness of the transparent conductive layer of the LED device in the central area is larger than the thickness of the transparent conductive layer of the LED device in the annular area.

[0007] Optionally, the substrate is a wafer, the central area is circular, the annular area is annular, and the central area and the annular area are concentrically distributed.

[0008] Optionally, a ratio of a radius of the central region to a radius of the substrate is 0.8 to 0.9, and a ratio of a width of the annular region to a radius of the substrate is 0.1 to 0.2.

[0009] Optionally, the annular area includes multiple sub-annular areas, which are sequentially surrounded by the central area; for any two adjacent sub-annular areas among the multiple sub-annular areas, the maximum width of the first through hole of the LED device in the sub-annular area close to the central area is greater than the maximum width of the first through hole of the LED device in the sub-annular area away from the central area, and the thickness of the transparent conductive layer of the LED device in the sub-annular area close to the central area is greater than the thickness of the transparent conductive layer of the LED device in the sub-annular area away from the central area.

[0010] Optionally, the annular area includes a first sub-annular area, a second sub-annular area and a third sub-annular area sequentially surrounding the central area; the ratio of the width of the first sub-annular area to the radius of the substrate is 0.05 to 0.15, the ratio of the width of the second sub-annular area to the radius of the substrate is 0.03 to 0.1, and the ratio of the width of the third sub-annular area to the radius of the substrate is 0.02 to 0.05.

[0011] Optionally, the first through holes of each of the LED devices have the same shape, the maximum width of the first through holes of the LED devices in the first sub-annular area is 6 μm to 8 μm, the maximum width of the first through holes of the LED devices in the second sub-annular area is 4 μm to 6 μm, and the maximum width of the LED devices in the third sub-annular area is 3 μm to 5 μm.

[0012] Optionally, the maximum width of the first through holes of the LED devices in the central region is 9 μm to 11 μm.

[0013] Optionally, the LED device includes a first light-emitting unit, a second light-emitting unit, an insulating layer and a transparent conductive layer, the first light-emitting unit and the second light-emitting unit both include a first semiconductor layer, a multi-quantum well layer and a second semiconductor layer stacked in sequence, and the second semiconductor layer has a groove exposing the first semiconductor layer; the insulating layer has a first through hole exposing the second semiconductor layer of the first light-emitting unit and the second semiconductor layer of the second light-emitting unit, and a second through hole exposing the groove of the first light-emitting unit and the groove of the second light-emitting unit; the transparent conductive layer is located on the two second semiconductor layers and is connected to the two second semiconductor layers through the two first through holes respectively; the first semiconductor layer of the first light-emitting unit is electrically connected to the second semiconductor layer of the second light-emitting unit.

[0014] Optionally, the LED device further includes a connecting electrode, a first electrode, and a second electrode, the connecting electrode being located on the insulating layer, and the first part of the connecting electrode being connected to the first semiconductor layer of the first light-emitting unit through the second through hole, and the second part of the connecting electrode being connected to the transparent conductive layer of the second light-emitting unit; the first electrode being located on the transparent conductive layer of the first light-emitting unit, the second electrode being located in the groove of the second light-emitting unit, and being connected to the first semiconductor layer through the second through hole.

[0015] Optionally, the transparent conductive layer includes two conductive parts, each of the conductive parts has a connected rectangular area and a raised area, the raised area is located on the long side of the rectangular area, one of the two conductive parts is located on the second semiconductor layer of the first light-emitting unit, and the other of the two conductive parts is located on the second semiconductor layer of the second light-emitting unit; the first light-emitting unit and the second light-emitting unit each have two grooves, the two grooves of the first light-emitting unit are located on both sides of the raised area corresponding to the first light-emitting unit, and the two grooves of the second light-emitting unit are located on both sides of the raised area corresponding to the second light-emitting unit.

[0016] Optionally, the center of the first through hole passes through the midline of the long side of the rectangular area and the midline of the perpendicular line between the side of the convex area away from the rectangular area and the long side of the rectangular area away from the convex area.

[0017] Optionally, the first light-emitting unit has two first electrodes, and the two first electrodes are symmetrically distributed on the transparent conductive layer; the second light-emitting unit has two second electrodes, and the two second electrodes are respectively located in two grooves of the second light-emitting unit and are symmetrically arranged; the two first electrodes and the two second electrodes are symmetrically distributed.

[0018] Optionally, the light emitting diode includes two connecting electrodes, and the two connecting electrodes are symmetrically arranged.

[0019] Optionally, the insulating layer includes an aluminum oxide layer and a silicon oxide layer stacked in sequence.

[0020] In another aspect, a method for preparing an article is provided. The method comprises: providing a substrate having a central region and an annular region, the annular region surrounding the central region; forming a plurality of LED devices on the substrate, each LED device comprising an epitaxial layer, an insulating layer, and a transparent conductive layer sequentially stacked on the substrate, the insulating layer having a first through-hole exposing the epitaxial layer, the transparent conductive layer being connected to the epitaxial layer via the first through-hole; wherein the plurality of LED devices are arranged in both the central region and the annular region, the area of ​​the contact surface between the first through-hole of the LED device in the central region and the epitaxial layer being larger than the area of ​​the contact surface between the first through-hole of the LED device in the annular region and the epitaxial layer, and the thickness of the transparent conductive layer of the LED device in the central region being larger than the thickness of the transparent conductive layer of the LED device in the annular region.

[0021] In yet another aspect, an LED is provided, comprising the aforementioned LED device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] FIG1 is a schematic structural diagram of a product provided by an embodiment of the present disclosure;

[0024] FIG2 is a schematic structural diagram of an LED provided by an embodiment of the present disclosure;

[0025] FIG3 is a cross-sectional view taken along line AA of FIG2 ;

[0026] FIG4 is a partial enlarged view of point M in FIG1 ;

[0027] FIG5 is a flow chart of a method for preparing a product provided in an embodiment of the present disclosure.

[0028] The descriptions of the marks in the figure are as follows: 10, substrate; 11, central area; 12, annular area; 121, first sub-annular area; 122, second sub-annular area; 123, third sub-annular area; 200, LED device; 210, epitaxial layer; 211, first light-emitting unit; 212, second light-emitting unit; 213, first semiconductor layer; 214, multi-quantum well layer; 215, second semiconductor layer; 220, insulating layer; 221, first through hole; 222, second through hole; 230, transparent conductive layer; 230a, conductive part; 231, rectangular area; 232, raised area; 30, connecting electrode; 31, first electrode; 32, second electrode; 40, passivation layer; 51, first solder joint block; 52, second solder joint block. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0030] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by persons of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” “third,” and similar words used in the patent specification and claims of this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish between different components. Similarly, terms such as “a” or “an” do not indicate a quantitative limitation, but rather indicate the presence of at least one. Terms such as “include” or “comprise” mean that the elements or objects preceding “include” or “comprises” encompass the elements or objects listed following “include” or “comprises,” and their equivalents, and do not exclude other elements or objects. Terms such as “connected” or “connected” are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Terms such as “upper,” “lower,” “left,” “right,” “top,” and “bottom” are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0031] LEDs typically consist of a substrate, epitaxial layers, a transparent conductive layer, and electrodes. The epitaxial layers include a first semiconductor layer, a multi-quantum well layer, and a second semiconductor layer, stacked sequentially on the substrate. The transparent conductive layer is located on the second semiconductor layer, and the electrodes are located on the transparent conductive layer. The transparent conductive layer can spread current to various areas of the second semiconductor layer. The transparent conductive layer is typically produced using an evaporation machine.

[0032] Due to the volatility of vapor deposition equipment, the transparent conductive layers of multiple LEDs formed in different areas of the substrate can have uneven thickness. Specifically, the thickness of the transparent conductive layer of the LEDs in the center of the substrate is greater than that of the LEDs in the edge areas of the substrate. The thinner the transparent conductive layer, the less light it absorbs, and the higher the brightness of the corresponding LED. Conversely, the thicker the transparent conductive layer, the more light it absorbs, and the lower the brightness of the corresponding LED. Therefore, the uneven thickness of the transparent conductive layer in different areas of the substrate will result in poor brightness consistency of the LEDs in different areas of the substrate.

[0033] To this end, an embodiment of the present disclosure provides a product for preparing LEDs, which can improve the brightness consistency of multiple LEDs formed based on the same substrate.

[0034] Figure 1 is a schematic diagram of the structure of an article provided by an embodiment of the present disclosure. As shown in Figure 1 , the article includes a substrate 10 and a plurality of LED devices 200 disposed on substrate 10. Substrate 10 has a central region 11 and an annular region 12. Annular region 12 surrounds central region 11, and multiple LED devices 200 are arranged in both central region 11 and annular region.

[0035] Figure 2 is a schematic diagram of the structure of an LED provided by an embodiment of the present disclosure. Figure 3 is a cross-sectional view taken along line AA of Figure 2. As shown in Figures 2 and 3, each LED device 200 includes an epitaxial layer 210, an insulating layer 220, and a transparent conductive layer 230 sequentially stacked on a substrate 10. The insulating layer 220 has a first through-hole 221 exposing the epitaxial layer 210. The transparent conductive layer 230 is connected to the epitaxial layer 210 through the first through-hole 221.

[0036] As shown in Figure 1, the maximum width of the first through hole 221 of the LED device 200 in the central area 11 is greater than the maximum width of the first through hole 221 of the LED device 200 in the annular area 12, and the thickness of the transparent conductive layer 230 of the LED device 200 in the central area 11 is greater than the thickness of the transparent conductive layer 230 of the LED device 200 in the annular area 12.

[0037] In the embodiment of the present disclosure, the maximum width of the first through hole refers to the distance between the two points on the contact surface between the first through hole and the epitaxial layer that are farthest apart.

[0038] For example, when the first through hole is a circular hole, the maximum width of the first through hole is the diameter of the first through hole. Here, the circular hole refers to a hole with a circular cross section parallel to the supporting surface of the substrate.

[0039] For another example, when the first through hole is a rectangular hole, the maximum width of the first through hole is the length of the diagonal line of the first through hole. Here, the rectangular hole refers to a hole with a rectangular cross section parallel to the supporting surface of the substrate.

[0040] The supporting surface of the substrate refers to the surface of the substrate having the LED device.

[0041] In the disclosed embodiment, the first through holes 221 of each LED device 200 have the same shape, for example, all are circular or rectangular. When the first through holes 221 of each LED device 200 have the same shape, the maximum width of the first through hole is positively correlated with the area of ​​the contact surface between the first through hole and the epitaxial layer. The larger the maximum width of the first through hole, the larger the area of ​​the contact surface between the first through hole and the epitaxial layer; conversely, the smaller the maximum width of the first through hole, the smaller the area of ​​the contact surface between the first through hole and the epitaxial layer.

[0042] In other embodiments, all LED devices 200 may have different first through holes 221. For example, the first through holes 221 of the LED devices 200 in the central region 11 may be circular, while the first through holes 221 of the LED devices 200 in the annular region 12 may be rectangular. The present disclosure does not impose any restrictions on this, as long as the area of ​​the contact surface between the first through holes 221 and the epitaxial layer in the LED devices 200 in the central region 11 is greater than the area of ​​the contact surface between the first through holes 221 and the epitaxial layer in the LED devices 200 in the annular region 12.

[0043] The LED device 200 provided in the embodiment of the present disclosure includes an epitaxial layer 210, an insulating layer 220, and a transparent conductive layer 230 stacked in sequence. The transparent conductive layer 230 is connected to the underlying epitaxial layer 210 via a first through-hole 221 in the insulating layer 220. The light-emitting area of ​​the LED device 200 is limited to the area of ​​the first through-hole 221.

[0044] Furthermore, the maximum width of the first through hole 221 in the LED device 200 in the central region 11 is greater than the maximum width of the first through hole 221 in the LED device 200 in the annular region 12 .

[0045] This means that the contact surface area between the first through-holes 221 of the LED devices 200 near the edge of the substrate 10 and the epitaxial layer 210 is smaller, while the contact surface area between the first through-holes 221 of the LED devices 200 near the center of the substrate 10 and the epitaxial layer 210 is larger. If the thickness of the transparent conductive layer 230 deposited in the central region 11 of the substrate is greater than that of the transparent conductive layer 230 at the edge of the substrate, the smaller contact surface area corresponding to the first through-holes 221 of the LED devices 200 at the edge of the substrate 10 reduces the light-emitting area of ​​the LED devices 200, thereby offsetting the improved luminous efficiency due to the thinner thickness of the transparent conductive layer 230. Similarly, the larger contact surface area corresponding to the first through-holes 221 of the LED devices 200 at the center of the substrate 10 increases the light-emitting area of ​​the LED devices 200, thereby reducing the problem of increased light absorption due to the thicker transparent conductive layer 230. Therefore, the embodiments of the present disclosure can improve the consistency of LED brightness in different regions of the substrate.

[0046] During implementation, the evaporation machine used to deposit the transparent conductive layer 230 can be a plasma-enhanced chemical vapor deposition (PECVD) machine. Magnetron sputtering is used to form the transparent conductive layer 230. Due to the volatility of the PECVD machine, the thickness of the transparent conductive layer 230 formed on the substrate 10 can be uneven. Furthermore, the thickness of the transparent conductive layer 230 of the LED device 200 located in the central region 11 of the substrate 10 is greater than the thickness of the transparent conductive layer 230 of the LED device 200 located in the annular region 12 at the edge of the substrate 10.

[0047] Optionally, as shown in FIG. 1 , the substrate 10 is a wafer, the central region 11 is circular, the annular region 12 is annular, and the annular region 12 is concentrically distributed with the central region 11 .

[0048] In the embodiment of the present disclosure, the substrate 10 is a four-inch wafer with a radius of 50,000 μm. The embodiment of the present disclosure does not limit the size of the substrate 10 and can be any size that causes uneven thickness of the transparent conductive layer 230 .

[0049] Optionally, the substrate is a sapphire substrate, a silicon substrate or a silicon carbide substrate. The substrate can be a flat substrate or a patterned substrate.

[0050] In some examples, the substrate is a sapphire substrate. Sapphire substrates have high light transmittance, meaning they are transparent. Furthermore, sapphire is a hard material with relatively stable chemical properties, which enables the LED to have good luminous effects and stability.

[0051] Alternatively, the transparent conductive layer 230 may be an indium tin oxide (ITO) layer. The ITO layer has good transmittance and low resistivity. Using an ITO layer as the transparent conductive layer 230 allows more light to be transmitted through the transparent conductive layer 230, thereby ensuring a good light extraction effect. Furthermore, due to its low resistivity, it also facilitates carrier conduction and improves injection efficiency.

[0052] For example, the transparent conductive layer 230 can be an indium zinc oxide (IZO) layer. IZO layers have good transmittance and low resistivity. Using an IZO layer as the transparent conductive layer 230 allows more light to be transmitted through the transparent conductive layer 230, thereby ensuring effective light extraction. Furthermore, due to its low resistivity, it facilitates carrier conduction and improves injection efficiency.

[0053] Exemplarily, the thickness of the transparent conductive layer 230 may be 600 angstroms to 2000 angstroms. For example, the thickness of the transparent conductive layer is 1500 angstroms.

[0054] Exemplarily, the ratio of the radius of the central region 11 to the radius of the substrate 10 is 0.8 to 0.9.

[0055] When the evaporation machine forms the transparent conductive layer 230, the thickness of most of the film layer located in the center of the substrate 10 is uniform. Therefore, the ratio of the radius of the central region 11 to the radius of the substrate 10 is determined based on the thickness of the transparent conductive layer 230 in each LED device. This ensures that transparent conductive layers 230 of the same thickness can be connected to the epitaxial layer 210 through first through-holes 221 of the same size, thereby improving the brightness consistency of the LED.

[0056] For example, the ratio of the radius of the central region 11 to the radius of the substrate 10 is 0.85, and the thickness of the transparent conductive layer 230 located in the central region 11 on the substrate 10 is 900 angstroms.

[0057] Optionally, the maximum width of the first through hole 221 of the LED device 200 in the central region 11 is 9 μm to 11 μm. For example, the maximum width of the first through hole 221 of the LED device 200 in the central region 11 may be 10 μm.

[0058] When the thickness of the transparent conductive layer 230 is 900 angstroms, the maximum width of the first through hole 221 of the LED device 200 in the central area 11 is limited to the above range, which can increase the light-emitting area of ​​the LED device 200 in the central area 11 and increase the brightness so that the brightness of the LED devices 200 in various areas on the substrate 10 tends to be consistent.

[0059] Exemplarily, the ratio of the width of the annular region 12 to the radius of the substrate 10 is 0.1 to 0.2. That is, the region excluding the central region 11 is regarded as the annular region 12. For example, the ratio of the width of the annular region 12 to the radius of the substrate 10 is 0.15.

[0060] When the evaporation machine forms the transparent conductive layer 230, the thickness of the film layer at the edge of the substrate 10 is less than that of the film layer in the central region 11. Therefore, the transparent conductive layer 230 in the annular region 12 is thinner and is connected to the epitaxial layer 210 via the smaller first through-hole 221. This reduces the brightness of the LED in the annular region 12 and makes the brightness of the LED devices at different locations on the substrate 10 more uniform.

[0061] It should be noted that the number of LED devices 200 in Figure 1 is for illustration only. In actual production, the number of LED devices 200 will far exceed the number shown. Due to the relatively small number of LED devices 200 shown in Figure 1, for ease of illustration, the circular central region 11 does not encompass all of the LED devices 220 where the largest first through-holes 221 are located. In actual applications, the transparent conductive layer 230 in the circular central region 11 is thicker and can encompass all of the LED devices 220 where the largest first through-holes 221 are located.

[0062] Fig. 4 is a partial enlarged view of point M in Fig. 1. As shown in Fig. 4, the annular region 12 includes a first sub-annular region 121, a second sub-annular region 122 and a third sub-annular region 123 which surround the central region 11 in sequence.

[0063] Exemplarily, the ratio of the width of the first sub-annular region 121 to the radius of the substrate 10 is 0.05 to 0.15. For example, the ratio of the width of the first sub-annular region 121 to the radius of the substrate 10 is 0.08.

[0064] In the embodiment of the present disclosure, the thickness of the transparent conductive layer 230 in the first sub-annular region 121 is 860 angstroms.

[0065] Since the thickness of the transparent conductive layer 230 in the first sub-annular region 121 is smaller than the thickness of the transparent conductive layer 230 in the central region 11, the maximum width of the first through hole 221 in the first sub-annular region 121 can be smaller than the maximum width of the first through hole 221 in the central region 11 to balance the brightness of the LED device 200 in the first sub-annular region 121 and the central region 11.

[0066] Optionally, the maximum width of the first through hole 221 of the LED device 200 in the first sub-annular region 121 is 6 μm to 8 μm. Exemplarily, the maximum width of the first through hole 221 of the LED device 200 in the first sub-annular region 121 is 7 μm.

[0067] When the thickness of the transparent conductive layer 230 in the first sub-annular region 121 is 860 angstroms, the maximum width of the first through hole 221 of the LED device 200 in the first sub-annular region 121 is limited to the above range. Compared with the central region, the maximum width of the first through hole 221 in the first sub-annular region 121 is reduced, so that the area of ​​the first through hole through which the transparent conductive layer 230 injects current into the epitaxial layer is smaller, thereby reducing the brightness of the LED device 200 in the first sub-annular region 121, so that the brightness of the LED devices 200 in various regions on the substrate 10 tends to be consistent.

[0068] For example, the ratio of the width of the second sub-annular region 122 to the radius of the substrate 10 is 0.05 to 0.1. For example, the ratio of the width of the second sub-annular region 121 to the radius of the substrate 10 is 0.05.

[0069] In the embodiment of the present disclosure, the thickness of the transparent conductive layer 230 in the second sub-annular region 122 is 840 angstroms.

[0070] Since the thickness of the transparent conductive layer 230 in the second sub-annular region 122 is smaller than the thickness of the transparent conductive layer 230 in the central region 11 in the first sub-annular region 121, the maximum width of the first through hole 221 in the second sub-annular region 122 can be smaller than the maximum width of the first through hole 221 in the first sub-annular region 121 to balance the brightness of the LED device 200 in the two sub-regions.

[0071] Optionally, the maximum width of the first through hole 221 of the LED device 200 in the second sub-annular region 122 is 4 μm to 6 μm. Exemplarily, the maximum width of the first through hole 221 of the LED device 200 in the second sub-annular region 122 is 5.5 μm.

[0072] It should be noted that the maximum width of the first through hole 221 of the LED device 200 in the second sub-annular area 122 is smaller than the maximum width of the first through hole 221 of the LED device 200 in the first sub-annular area 121; when the maximum width of the first through hole 221 of the LED device 200 in the second sub-annular area 122 is 6 μm, the maximum width of the first through hole 221 of the LED device 200 in the first sub-annular area 121 needs to be greater than 6 μm.

[0073] When the thickness of the transparent conductive layer 230 in the second sub-annular region 122 is 840 angstroms, the maximum width of the first through hole 221 of the LED device 200 in the second sub-annular region 122 is limited to the above range. Compared with the first sub-annular region, the maximum width of the first through hole in the second sub-annular region is further reduced, so that the area of ​​the first through hole for the transparent conductive layer to inject current into the epitaxial layer is smaller, thereby reducing the brightness of the LED device 200 in the second sub-annular region, so that the brightness of the LED devices 200 in various areas on the substrate 10 tends to be consistent.

[0074] Exemplarily, the ratio of the width of the third sub-annular region 123 to the radius of the substrate 10 is 0.02 to 0.05. For example, the ratio of the width of the third sub-annular region 123 to the radius of the substrate 10 is 0.02.

[0075] In the embodiment of the present disclosure, the thickness of the transparent conductive layer 230 in the third sub-annular region 123 is 820 angstroms.

[0076] Since the thickness of the transparent conductive layer 230 in the third sub-annular region 123 is smaller than the thickness of the transparent conductive layer 230 in the central region 11 in the second sub-annular region 122, the maximum width of the first through hole 221 in the third sub-annular region 123 can be smaller than the maximum width of the first through hole 221 in the second sub-annular region 122 to balance the brightness of the LED device 200 in the two sub-regions.

[0077] Optionally, the maximum width of the first through hole 221 of the LED device 200 in the third sub-annular region 123 is 3 μm to 5 μm. Exemplarily, the maximum width of the first through hole 221 of the LED device 200 in the third sub-annular region 123 is 4 μm.

[0078] It should be noted that the maximum width of the first through hole 221 of the LED device 200 in the third sub-annular area 123 is smaller than the maximum width of the first through hole 221 of the LED device 200 in the second sub-annular area 122; when the maximum width of the first through hole 221 of the LED device 200 in the third sub-annular area 123 is 4 μm, the maximum width of the first through hole 221 of the LED device 200 in the second sub-annular area 122 needs to be greater than 4 μm; when the maximum width of the first through hole 221 of the LED device 200 in the third sub-annular area 123 is 5 μm, the maximum width of the first through hole 221 of the LED device 200 in the second sub-annular area 122 needs to be greater than 5 μm.

[0079] When the thickness of the transparent conductive layer 230 in the third sub-annular region 123 is 820 angstroms, the maximum width of the first through hole 221 of the LED device 200 in the third sub-annular region 123 is limited to the above range. Compared with the second sub-annular region 122, the maximum width of the first through hole in the third sub-annular region 123 is further reduced, so that the area of ​​the first through hole for the transparent conductive layer to inject current into the epitaxial layer is smaller, thereby reducing the brightness of the LED device 200 in the third sub-annular region, so that the brightness of the LED devices 200 in various areas on the substrate 10 tends to be consistent.

[0080] It should be noted that, in Figures 1 and 4, the annular region 12 is illustrated as including three sub-annular regions. In other embodiments, the annular region 12 may not be divided into sub-annular regions, or may include two, four, or more sub-annular regions. In the embodiment of the present disclosure, the number and division positions of the annular regions may be determined based on the thickness of the transparent conductive layer 230 formed on the substrate, and the embodiment of the present disclosure does not impose any limitation on this.

[0081] When the number of sub-annular regions included in the annular region 12 is greater than one, for any two adjacent sub-annular regions, the maximum width of the first through-hole 221 of the LED device 200 in the sub-annular region near the central region 11 is greater than the maximum width of the first through-hole 221 of the LED device 200 in the sub-annular region far from the central region 11, and the thickness of the transparent conductive layer 230 of the LED device 200 in the sub-annular region near the central region 11 is greater than the thickness of the transparent conductive layer 230 of the LED device 200 in the sub-annular region far from the central region 11. In other words, the maximum width of the first through-hole 221 of the LED device in each sub-annular region decreases along a direction away from the center of the substrate 10, and the thickness of the transparent conductive layer 230 of the LED device in each annular region decreases along a direction away from the center of the substrate 10.

[0082] As shown in FIG3 , in one implementation, the epitaxial layer 210 of each LED device 200 includes a first light-emitting unit 211 and a second light-emitting unit 212 arranged at intervals. The first light-emitting unit 211 and the second light-emitting unit 212 each include a first semiconductor layer 213, a multi-quantum well layer 214, and a second semiconductor layer 215 stacked in sequence. The second semiconductor layer 215 has a groove that exposes the first semiconductor layer 213. The first semiconductor layer 213 of the first light-emitting unit 211 is electrically connected to the second semiconductor layer 215 of the second light-emitting unit 212.

[0083] Illustratively, one of the first semiconductor layer 213 and the second semiconductor layer 215 is a p-type layer, and the other of the first semiconductor layer 213 and the second semiconductor layer 215 is an n-type layer.

[0084] Illustratively, the first semiconductor layer 213 is an n-type layer, and the second semiconductor layer 215 is a p-type layer.

[0085] For example, the first semiconductor layer 213 is a silicon-doped n-type GaN layer. The thickness of the n-type GaN layer may be 0.5 μm to 3 μm. As shown in FIG3 , the groove exposes the n-type GaN layer.

[0086] For example, the multi-quantum well layer 214 includes alternately grown InGaN quantum well layers and GaN quantum barrier layers, wherein the multi-quantum well layer 214 may include 3 to 8 periods of alternately stacked InGaN quantum well layers and GaN quantum barrier layers.

[0087] As an example, in the embodiment of the present disclosure, the multi-quantum well layer 214 includes five periods of alternately stacked InGaN quantum well layers and GaN quantum barrier layers.

[0088] By way of example, the thickness of the multi-quantum well layer 214 may be 150 nm to 200 nm.

[0089] For example, the second semiconductor layer 215 is a magnesium-doped p-type GaN layer, and the thickness of the p-type GaN layer may be 0.5 μm to 3 μm.

[0090] In the embodiment of the present disclosure, after the current is transmitted to the transparent conductive layer, the current on the transparent conductive layer flows downwardly into the epitaxial layer from the first through hole in the insulating layer, so that the epitaxial layer emits light.

[0091] Because the transparent conductive layer can only contact the underlying second semiconductor layer through the first through-hole, the second semiconductor layer in other areas is in direct contact with the insulating layer. Without the current spreading and ohmic contact of the transparent conductive layer, the second semiconductor layer in these areas emits almost no light. Therefore, the area of ​​the epitaxial layer corresponding to the first through-hole is the epitaxial layer's light-emitting area, and the area defined by the first through-hole is the epitaxial layer's light-emitting area.

[0092] As shown in FIG3 , the insulating layer 220 covers the first light-emitting unit 211 and the second light-emitting unit 212 and is located on the surface of the substrate 10. The insulating layer 220 has first through holes 221 that expose the two second semiconductor layers 215, and second through holes 222 that expose the grooves of the first light-emitting unit 211 and the grooves of the second light-emitting unit 212. The transparent conductive layer 230 is located on the two second semiconductor layers 215 and is connected to the two second semiconductor layers 215 via the two first through holes 221.

[0093] In the above implementation, each epitaxial layer 210 includes two light-emitting units arranged side by side. Both light-emitting units include a first semiconductor layer 213, a multi-quantum well layer 214, and a second semiconductor layer 215 stacked in sequence. The insulating layer 220 of each light-emitting unit is provided with a first through-hole 221 exposing the second semiconductor layer 215. The transparent conductive layer 230 of each light-emitting unit is connected to the second semiconductor layer 215 via the first through-hole 221. Furthermore, the first semiconductor layer 213 of the first light-emitting unit 211 is electrically connected to the second semiconductor layer 215 of the second light-emitting unit 212. This connects the first light-emitting unit 211 and the second light-emitting unit 212 in series. By applying power to the second semiconductor layer 215 of the first light-emitting unit 211 and the first semiconductor layer 213 of the second light-emitting unit 212, both light-emitting units can be controlled to emit light simultaneously, thereby enhancing the luminous effect of the epitaxial layer 210. This LED device with multiple light-emitting units connected in series can be called a high-voltage LED device.

[0094] In the related art, for high-voltage LED devices, the light-emitting area is usually reduced to improve the uniformity of light emission. For example, when the size of the LED chip remains unchanged, the area of ​​the transparent conductive layer is reduced. Since the primary electrode needs to be connected to the second semiconductor layer through the transparent conductive layer (such as the first electrode 31 below), if the area of ​​the transparent conductive layer is too small, the primary electrode will cover the entire transparent conductive layer, and the light absorption of the primary electrode will seriously affect the light efficiency of the LED chip. In addition, if the area of ​​the transparent conductive layer is smaller than the area of ​​the primary electrode, part of the primary electrode will directly contact the second semiconductor layer, resulting in poor ohmic contact effect, which is not conducive to current expansion and is very likely to cause reliability problems.

[0095] In the disclosed embodiment, the area defined by the first through-holes 221 in the insulating layer 220 corresponds to the light-emitting area of ​​the epitaxial layer. This reduces the light-emitting area without reducing the area of ​​the transparent conductive layer 230, thereby improving the uniformity of the LED device's light emission. Furthermore, since the area of ​​the transparent conductive layer 230 does not need to be reduced, it can completely separate the primary electrode from the second semiconductor layer, avoiding the problem of poor ohmic contact.

[0096] Alternatively, the insulating layer 220 may be a single-layer structure or a multi-layer structure. The single-layer structure may be a silicon oxide layer, a silicon nitride layer, or an aluminum oxide layer. The multi-layer structure may be formed by stacking at least two of the silicon oxide layer, the silicon nitride layer, or the aluminum oxide layer.

[0097] In some examples, the insulating layer 220 includes an aluminum oxide layer and a silicon oxide layer stacked in sequence. Because the etching rate of the aluminum oxide layer is lower than that of the silicon oxide layer, the opening formed by etching in the aluminum oxide layer is smaller, while the opening formed by etching in the silicon oxide layer is larger. Thus, after the aluminum oxide layer and the silicon oxide layer are stacked, the two openings can be combined to form a through hole with inclined hole walls.

[0098] Optionally, the thickness of the silicon oxide layer is greater than that of the aluminum oxide layer, so that the hole wall of the first through hole and the surface of the insulating layer away from the substrate form a smaller angle, which is convenient for subsequent transparent conductive layer coverage and better coverage.

[0099] Exemplarily, the thickness of the aluminum silicon oxide layer is 600 angstroms to 1200 angstroms. For example, the thickness of the aluminum silicon oxide layer is 1000 angstroms; and the thickness of the silicon oxide layer is 2400 angstroms to 5000 angstroms. For example, the thickness of the silicon oxide layer is 3000 angstroms.

[0100] In the embodiment of the present disclosure, as shown in FIG3 , the first through hole 221 is a tapered hole, with the larger end of the first through hole 221 being away from the substrate 10. The cross-section of the first through hole 221 in a direction parallel to the substrate 10 is circular. In other embodiments, the cross-section of the first through hole 221 in a direction parallel to the substrate 10 may also have other shapes, such as a rectangle.

[0101] Optionally, the angle between the wall of the first through hole 221 and the surface of the insulating layer 220 away from the substrate 10 is 10° to 60°. For example, the angle between the wall of the first through hole 221 and the surface of the insulating layer 220 away from the substrate 10 is 30°.

[0102] In other embodiments, the first through hole 221 is a cylindrical hole.

[0103] For example, as shown in Figure 3, each LED device 200 also includes a connecting electrode 30, which is located on the insulating layer 220, and the first part of the connecting electrode 30 is connected to the first semiconductor layer 213 of the first light-emitting unit 211 through the second through hole 222, and the second part of the connecting electrode 30 is connected to the transparent conductive layer 230 of the second light-emitting unit 212.

[0104] The connection electrode 30 is provided so that the connection electrode 30 can connect the first semiconductor layer 213 of the first light emitting unit 211 and the transparent conductive layer 230 of the second light emitting unit 212 respectively, thereby achieving the purpose of connecting the first light emitting unit 211 and the second light emitting unit 212 in series.

[0105] For example, as shown in Figures 2 and 3, the connecting electrode 30 is a long strip structure, one end of the long strip structure is connected to the first semiconductor layer 213 of the first light-emitting unit 211 through the second through hole 222, and the other end of the long strip structure is connected to the transparent conductive layer 230 of the second light-emitting unit 212. The middle part of the long strip structure is located on the insulating layer 220 between the first light-emitting unit 211 and the second light-emitting unit 212.

[0106] In another implementation, the epitaxial layer of each LED device includes a first semiconductor layer, a multi-quantum well layer, and a second semiconductor layer stacked in sequence, with each second semiconductor layer having a groove exposing the first semiconductor layer. That is, each LED device includes only one light-emitting unit.

[0107] The insulating layer covers the epitaxial layer and is located on the surface of the substrate. The insulating layer has a first through hole exposing the second semiconductor layer and a second through hole exposing the groove. The transparent conductive layer is located on the second semiconductor layer and connected to the second semiconductor layer through the first through hole.

[0108] For the relevant contents of the first semiconductor layer, the second semiconductor layer, and the multi-quantum well layer, please refer to the previous embodiment, and detailed description is omitted here.

[0109] Optionally, as shown in Figure 3, each LED device 200 also includes a first electrode 31 and a second electrode 32, the first electrode 31 is located on the transparent conductive layer 230 of the first light-emitting unit 211, and the second electrode 32 is located in the groove of the second light-emitting unit 212 and is connected to the first semiconductor layer 213 through the second through hole 222.

[0110] When the first semiconductor layer 213 is an n-type layer and the second semiconductor layer 215 is a p-type layer, the first electrode 31 is a p-electrode and the second electrode 32 is an n-electrode. The first electrode 31 is located on the first light-emitting unit 211 and is connected to the transparent conductive layer 230. The second electrode 32 is located in the groove and is connected to the n-type layer exposed in the groove. In this way, only the first electrode 31 and the second electrode 32 need to be energized to achieve the purpose of controlling the light emission of the two light-emitting units, thereby improving the light efficiency of the LED device 200.

[0111] Optionally, as shown in FIG3 , the LED device 200 further includes a passivation layer 40, a first soldering block 51, and a second soldering block 52. The passivation layer 40 is located on the insulating layer 220 and within the groove, and covers the first electrode 31 and the second electrode 32. The passivation layer 40 has a first recessed hole exposing the first electrode 31 and a second recessed hole exposing the second electrode 32. The first soldering block 51 and the second soldering block 52 are both located on the surface of the passivation layer 40 away from the substrate 10, and the first soldering block 51 is connected to the first electrode 31 through the first recessed hole, and the second soldering block 52 is connected to the second electrode 32 through the second recessed hole.

[0112] Exemplarily, the passivation layer 40 has two first recessed holes exposing the first electrode 31 and two second recessed holes exposing the second electrode 32, so that the solder joint blocks provided on the surface of the passivation layer 40 away from the substrate 10 are respectively connected to the two electrodes (i.e., the first electrode 31 and the second electrode 32), so that an external power source supplies power to the two electrodes through the recessed holes.

[0113] For example, the passivation layer 40 may be a distributed Bragg reflector (DBR) layer, which includes a plurality of periodically alternating SiO2 layers and TiO2 layers. The number of periods in the DBR layer may be between 20 and 50. For example, the number of periods in the DBR layer is 32.

[0114] The thickness of the SiO2 layer in the DBR layer may be 800 angstroms to 1200 angstroms, and the thickness of the TiO2 layer may be 500 angstroms to 900 angstroms.

[0115] In addition to the passivation effect, the DBR layer can also reflect the light emitted from the multi-quantum well layer 214 to the DBR layer to the substrate 10, thereby improving the light extraction effect.

[0116] Optionally, the first soldering point block 51 and the second soldering point block 52 are both metal structures, and may be single-layer metal structures or multi-layer metal structures stacked in sequence.

[0117] Exemplarily, each of the first solder bump 51 and the second solder bump 52 may include a first Al layer, a first Ti layer, a second Al layer, a second Ti layer, and an Au layer stacked in sequence.

[0118] The thickness of the first Al layer is 8000 angstroms to 12000 angstroms, the thickness of the first Ti layer is 100 angstroms to 500 angstroms, the thickness of the second Al layer is 8000 angstroms to 12000 angstroms, the thickness of the second Ti layer is 500 angstroms to 1500 angstroms, and the thickness of the Au layer is 2000 angstroms to 5000 angstroms.

[0119] For example, the thickness of the first Al layer is 10,000 angstroms, the thickness of the first Ti layer is 200 angstroms, the thickness of the second Al layer is 10,000 angstroms, the thickness of the second Ti layer is 1,000 angstroms, and the thickness of the Au layer is 3,000 angstroms.

[0120] In the embodiment of the present disclosure, the solder joint block may also be referred to as a pad electrode.

[0121] Optionally, as shown in FIG2 , the transparent conductive layer 230 includes two conductive portions 230 a. Each conductive portion 230 a has a connected rectangular region 231 and a raised region 232, with the raised region 232 located along the long side of the rectangular region 231. One conductive portion 230 a is located on the second semiconductor layer 215 of the first light-emitting unit 211, and the other conductive portion 230 a is located on the second semiconductor layer 215 of the second light-emitting unit 212.

[0122] The first light-emitting unit 211 and the second light-emitting unit 212 each have two grooves X. In the first light-emitting unit 211, the two grooves X are located on both sides of the raised area 232 corresponding to the first light-emitting unit 211. In the second light-emitting unit 212, the two grooves X are located on both sides of the raised area 232 corresponding to the second light-emitting unit 212.

[0123] By designing the transparent conductive layer to include two conductive portions, each consisting of a rectangular area and a raised area, the conductive portions form a convex shape. This allows the transparent conductive layer to cover a larger area of ​​the second semiconductor layer, facilitating flexible arrangement of the relative positions of the solder pads and electrodes. Furthermore, grooves are provided on both sides of the raised areas to facilitate electrical connection between the first and second light-emitting units, as well as between the second light-emitting unit and the second solder pad.

[0124] For example, as shown in Figure 2, the first light-emitting unit 211 and the second light-emitting unit 212 are connected in series via two connecting electrodes 30. A connecting electrode 30 is provided in each of the two grooves of the first light-emitting unit 211, thereby improving the connection reliability between the two light-emitting units. At the same time, the second solder joint 52 can also be connected to the first semiconductor layer 213 via the second electrodes 32 in the two grooves, thereby stably transmitting current to the first semiconductor layer of the epitaxial layer.

[0125] Exemplarily, the two connecting electrodes 30 are arranged symmetrically. As shown in FIG2 , the width of the portion of each connecting electrode 30 located in the groove is greater than the width of the portion of the connecting electrode 30 connected to the transparent conductive layer 230 of the second light-emitting unit 212. That is, in FIG2 , the width of the upper end of the connecting electrode 30 is greater than the width of the lower end of the connecting electrode 30, thereby improving the reliability of the connection between the connecting electrode 30 and the first semiconductor layer 213 of the first light-emitting unit 211. Here, the width refers to the dimension of the connecting electrode 30 in a direction perpendicular to the first light-emitting unit 211 and the second light-emitting unit 212.

[0126] 2 , the center of the first through hole 221 passes through the midline of the long side of the rectangular region 231 and the midline of the perpendicular line between the side of the raised region 232 away from the rectangular region 231 and the long side of the rectangular region 231 away from the raised region 232 .

[0127] In this way, the first through hole can be set at the geometric center of the convex transparent conductive layer, so that the light-emitting area of ​​the light-emitting unit is located in the center of the light-emitting unit, ensuring the light-emitting effect of the light-emitting unit.

[0128] Optionally, as shown in FIG2 , the first light-emitting unit 211 has two first electrodes 31 symmetrically distributed on the transparent conductive layer 230. The second light-emitting unit 212 has two second electrodes 32 symmetrically distributed in two grooves of the second light-emitting unit 212. The two first electrodes 31 and the two second electrodes 32 are symmetrically distributed.

[0129] In the above implementation, four electrodes (i.e., two first electrodes 31 and two second electrodes 32) are distributed at the four corners of the LED device, and the four electrodes are symmetrical to each other, so that current is injected from the edge of the LED device, and the first through hole of each light-emitting unit is set in the center of the light-emitting unit. Therefore, the current can be transmitted from the edge of the LED device to the middle, so that the current expands laterally, which can improve the current injection effect.

[0130] For example, the orthographic projection of the first electrode 31 on the supporting surface of the substrate 10 is located inside the orthographic projection of the transparent conductive layer 230 on the supporting surface of the substrate 10, and the orthographic projection of the first electrode 31 on the supporting surface of the substrate 10 does not overlap with the orthographic projection of the first through hole 221 on the supporting surface of the substrate 10. In this way, the first electrode 31 is prevented from absorbing light and affecting the luminous efficiency of the LED device.

[0131] FIG5 is a flow chart of a method for preparing a product provided by an embodiment of the present disclosure. The method is used to prepare the LED shown in FIG2. As shown in FIG5, the preparation method includes:

[0132] S11: providing a substrate.

[0133] Optionally, the substrate is a sapphire substrate, a silicon substrate or a silicon carbide substrate. The substrate can be a flat substrate or a patterned substrate.

[0134] As an example, the substrate is a sapphire substrate. Sapphire substrate is a commonly used substrate with mature technology and low cost. The sapphire substrate can be a patterned sapphire substrate or a flat sapphire substrate.

[0135] Optionally, before S12, the sapphire substrate may be pre-treated by placing the sapphire substrate in a metal-organic chemical vapor deposition (MOCVD) reaction chamber and baking the sapphire substrate for 12 to 18 minutes. As an example, in the embodiment of the present disclosure, the sapphire substrate is baked for 15 minutes.

[0136] Specifically, the baking temperature may be 1000° C. to 1200° C., and the pressure in the MOCVD reaction chamber during baking may be 100 mbar to 200 mbar.

[0137] S12: forming a plurality of LED devices on a substrate.

[0138] Each LED device includes an epitaxial layer, an insulating layer and a transparent conductive layer stacked in sequence on a substrate. The insulating layer has a first through hole exposing the epitaxial layer, and the transparent conductive layer is connected to the epitaxial layer through the first through hole.

[0139] In an embodiment of the present disclosure, a substrate has a central region and an annular region surrounding the central region, with multiple LED devices arranged in both the central region and the annular region. The area of ​​the contact surface between the first through-holes of the LED devices in the central region and the epitaxial layer is greater than the area of ​​the contact surface between the first through-holes of the LED devices in the annular region and the epitaxial layer, and the thickness of the transparent conductive layer of the LED devices in the central region is greater than the thickness of the transparent conductive layer of the LED devices in the annular region.

[0140] The formation of the LED device in S12 may include the following steps:

[0141] In the first step, a first light emitting unit and a second light emitting unit are formed on a substrate and arranged at intervals.

[0142] The first light-emitting unit and the second light-emitting unit both include a first semiconductor layer, a multi-quantum well layer, and a second semiconductor layer stacked in sequence, and the second semiconductor layer has a groove exposing the first semiconductor layer.

[0143] Optionally, in the first step, a first semiconductor layer, a multi-quantum well layer and a second semiconductor layer are sequentially formed on a sapphire substrate by MOCVD technology; and each film layer is processed by a patterning process to form a first light-emitting unit and a second light-emitting unit.

[0144] For example, the first semiconductor layer is an n-type GaN layer, the growth temperature of the n-type GaN layer may be 1000° C. to 1100° C., and the growth pressure of the n-type GaN layer may be 100 torr to 300 torr.

[0145] Optionally, the multi-quantum well layer includes alternating InGaN quantum well layers and GaN quantum barrier layers. During the growth of the multi-quantum well layer, the MOCVD chamber pressure is controlled at 200 Torr. During the growth of the InGaN quantum well layer, the chamber temperature is 760°C to 780°C. During the growth of the GaN quantum barrier layer, the chamber temperature is 860°C to 890°C.

[0146] For example, the second semiconductor layer is a p-type GaN layer. When growing the p-type GaN layer, the growth pressure of the p-type GaN layer may be 200 Torr to 600 Torr, and the growth temperature of the p-type GaN layer may be 800° C. to 1000° C.

[0147] Exemplarily, each film layer is processed by a patterning process to form the first light-emitting unit and the second light-emitting unit, including: etching the LED device area and forming a groove on the surface of the second semiconductor layer away from the substrate.

[0148] The etching of the grooves can be achieved by dry etching, or by using photolithography combined with wet etching, such as etching with a mixed solution of H3PO4 / H2SO4.

[0149] In the second step, an insulating layer is formed on the surface of the substrate, the first light emitting unit and the second light emitting unit.

[0150] The insulating layer has first through holes respectively exposing the two second semiconductor layers, and second through holes respectively exposing the groove of the first light emitting unit and the groove of the second light emitting unit.

[0151] In the embodiment of the present disclosure, the insulating layer includes an aluminum oxide layer and a silicon oxide layer stacked in sequence.

[0152] Optionally, forming the insulating layer may include: forming a silicon oxide aluminum layer on the surface of the substrate, the first light-emitting unit and the second light-emitting unit; forming a silicon oxide layer on the surface of the aluminum oxide layer; and forming a through hole in the insulating layer by etching.

[0153] Since the etching rate of the aluminum oxide layer is lower than that of the silicon oxide layer, the opening formed by etching on the aluminum oxide layer is smaller, while the opening formed by etching on the silicon oxide layer is larger. In this way, after the aluminum oxide layer and the silicon oxide layer are stacked, the two openings can be combined to form a through hole with inclined hole walls.

[0154] The thickness of the silicon oxide layer is greater than that of the aluminum oxide layer, which allows the hole wall of the first through hole to form a smaller angle with the surface of the insulating layer away from the substrate, facilitating subsequent covering with a transparent conductive layer and achieving better coverage.

[0155] In the third step, a transparent conductive layer is formed on the insulating layer. The transparent conductive layer is located on the two second semiconductor layers and is connected to the two second semiconductor layers through two first through holes respectively.

[0156] After forming the insulating layer, the preparation method further includes forming a transparent conductive layer on the surface of the insulating layer, and the transparent conductive layer extends to the surfaces of the second semiconductor layers of the two light-emitting units through the first through hole.

[0157] After step S12 , the method further includes: manufacturing a first electrode on the surface of the transparent conductive layer of the first light-emitting unit, and manufacturing a second electrode in the groove of the second light-emitting unit.

[0158] Among them, the first electrode is mainly composed of gold beryllium, and the second electrode is evaporated with gold germanium as the base material. When evaporating the gold germanium alloy, the evaporation power must be guaranteed to avoid the evaporation time exceeding seconds to prevent the deviation of the alloy composition, and annealing is performed.

[0159] Optionally, after forming the first electrode and the second electrode, the preparation method further includes: forming a passivation layer on the surface of the insulating layer, the surface of the transparent conductive layer, the surface of the first electrode, and the surface of the second electrode; after forming the passivation layer, etching the surface of the passivation layer to form a first recessed hole and a second recessed hole. The first recessed hole exposes the first electrode, and the second recessed hole exposes the second electrode.

[0160] After etching the passivation layer to form the first concave hole and the second concave hole, the preparation method further includes: making a first soldering point block and a second soldering point block on the surface of the passivation layer.

[0161] The first soldering point block is connected to the first electrode through the first concave hole, and the second soldering point block is connected to the second electrode through the second concave hole.

[0162] In the embodiment of the present disclosure, the preparation method may further include: forming a protective layer on the surface of the passivation layer.

[0163] For example, in the embodiment of the present disclosure, the protective layer may be a silicon oxide layer, and the thickness of the silicon oxide layer is 2000 angstroms.

[0164] Finally, the sapphire substrate can be invisible cut and cleaved, which can effectively reduce the loss of brightness. Then, the LED is tested.

[0165] The embodiment of the present disclosure further provides an LED, which includes the aforementioned LED device. Optionally, the LED further includes a substrate, and the LED device is located on the substrate.

[0166] The above description is merely an optional embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the scope of protection of the present disclosure.

Claims

1. A light emitting diode, characterized in that: The light emitting diode comprises a substrate (10), a first light emitting unit (211), a second light emitting unit (212), an insulating layer (220) and a transparent conductive layer (230); the first light emitting unit (211) and the second light emitting unit (212) are arranged at intervals and each comprises a first semiconductor layer (213), a multi-quantum well layer (214) and a second semiconductor layer (215) stacked in sequence; and the second semiconductor layer (215) has a groove exposing the first semiconductor layer (213); The insulating layer (220) covers the first light-emitting unit (211) and the second light-emitting unit (212), and is located on the surface of the substrate (10); the insulating layer (220) has first through holes (221) respectively exposing the two second semiconductor layers (215), and second through holes (222) respectively exposing the two grooves; The transparent conductive layer (230) is located on the two second semiconductor layers (215), and is connected to the two second semiconductor layers (215) through the two first through holes (221) respectively; The first semiconductor layer (213) of the first light-emitting unit (211) is electrically connected to the second semiconductor layer (215) of the second light-emitting unit (212).

2. The light emitting diode according to claim 1, characterized in that: The light emitting diode further comprises a connecting electrode (30), a first electrode (31) and a second electrode (32). The connecting electrode (30) is located on the insulating layer (220), and a first portion of the connecting electrode (30) is connected to the first semiconductor layer (213) of the first light-emitting unit (211) through the second through hole (222), and a second portion of the connecting electrode (30) is connected to the transparent conductive layer (230) of the second light-emitting unit (212); The first electrode (31) is located on the transparent conductive layer (230) of the first light-emitting unit (211), and the second electrode (32) is located in the groove of the second light-emitting unit (212) and is connected to the first semiconductor layer (213) through the second through hole (222).

3. The light emitting diode according to claim 1 or 2, characterized in that: The transparent conductive layer (230) comprises two conductive parts (230a), each of the conductive parts (230a) has a connected rectangular area (231) and a convex area (232), the convex area (232) is located on the long side of the rectangular area (231), one of the two conductive parts (230a) is located on the second semiconductor layer (215) of the first light-emitting unit (211), and the other of the two conductive parts (230a) is located on the second semiconductor layer (215) of the second light-emitting unit (212); The first light-emitting unit (211) and the second light-emitting unit (212) both have two grooves, the two grooves of the first light-emitting unit (211) are located on both sides of the raised area (232) corresponding to the first light-emitting unit (211), and the two grooves of the second light-emitting unit (212) are located on both sides of the raised area (232) corresponding to the second light-emitting unit.

4. The light emitting diode according to claim 3, characterized in that: The center of the first through hole (221) passes through the midline of the long side of the rectangular area (231), and passes through the midline of the perpendicular line between the side of the raised area (232) away from the rectangular area (231) and the long side of the rectangular area (231) away from the raised area (232).

5. The light emitting diode according to any one of claims 2 to 4, characterized in that: The first light-emitting unit (211) has two first electrodes (31), and the two first electrodes (31) are symmetrically distributed on the transparent conductive layer (230); The second light-emitting unit (212) has two second electrodes (32), and the two second electrodes (32) are respectively located in two grooves of the second light-emitting unit (212) and are arranged symmetrically; The two first electrodes (31) and the two second electrodes (32) are symmetrically distributed.

6. The light emitting diode according to any one of claims 2 to 5, characterized in that: The light emitting diode comprises two connecting electrodes (30), and the two connecting electrodes (30) are symmetrically arranged.

7. The light emitting diode according to any one of claims 1 to 5, characterized in that: The insulating layer (220) includes an aluminum oxide layer and a silicon oxide layer stacked in sequence.

8. A product, characterized in that The product comprises a substrate (10) and a plurality of light-emitting diode devices (200) located on the substrate (10), each of the light-emitting diode devices (200) comprising an epitaxial layer (210), an insulating layer (220) and a transparent conductive layer (230) sequentially stacked on the substrate (10), the insulating layer (220) having a first through hole (221) exposing the epitaxial layer (210), and the transparent conductive layer (230) being connected to the epitaxial layer (210) through the first through hole (221); The substrate (10) has a central region (11) and an annular region (12), wherein the annular region (12) Surrounding the central area (11), a plurality of the light emitting diode devices (200) are arranged in both the central area (11) and the annular area (12); The area of ​​the contact surface between the first through hole (221) of the light emitting diode device (200) in the central area (11) and the epitaxial layer is greater than the area of ​​the contact surface between the first through hole (221) of the light emitting diode device (200) in the annular area (12) and the epitaxial layer, and the thickness of the transparent conductive layer (230) of the light emitting diode device (200) in the central area (11) is greater than the thickness of the transparent conductive layer (230) of the light emitting diode device (200) in the annular area (12).

9. The product according to claim 8, characterized in that The substrate (10) is a disc, the central area (11) is circular, the annular area (12) is annular, and the central area (11) and the annular area (12) are concentrically distributed.

10. The product according to claim 9, characterized in that The ratio of the radius of the central region (11) to the radius of the substrate (10) is 0.8 to 0.9, and the ratio of the width of the annular region (12) to the radius of the substrate (10) is 0.1 to 0.

2.

11. The product according to claim 9 or 10, characterized in that The annular region (12) includes a plurality of sub-annular regions, and the plurality of sub-annular regions are sequentially surrounded by the central region (11); For any two adjacent sub-annular regions among the plurality of sub-annular regions, the maximum width of the first through hole (221) of the light emitting diode device (200) in the sub-annular region close to the central region (11) is greater than the maximum width of the first through hole (221) of the light emitting diode device (200) in the sub-annular region far from the central region (11), and the thickness of the transparent conductive layer (230) of the light emitting diode device (200) in the sub-annular region close to the central region (11) is greater than the thickness of the transparent conductive layer (230) of the light emitting diode device (200) in the sub-annular region far from the central region (11).

12. The product according to claim 11, characterized in that The annular region comprises a first sub-annular region (121), a second sub-annular region (122) and a third sub-annular region (123) which are sequentially surrounded outside the central region (11); The ratio of the width of the first sub-annular region (121) to the radius of the substrate (10) is 0.05 to 0.15, and the ratio of the width of the second sub-annular region (122) to the radius of the substrate (10) is The ratio of the width of the third sub-annular region (123) to the radius of the substrate (10) is 0.02 to 0.

05.

13. The product according to claim 12, characterized in that The first through holes (221) of the light emitting diode devices are of the same shape, the maximum width of the first through holes (221) of the light emitting diode devices (200) in the first sub-annular region (121) is 6 μm to 8 μm, the maximum width of the first through holes (221) of the light emitting diode devices (200) in the second sub-annular region (122) is 4 μm to 6 μm, and the maximum width of the light emitting diode devices (200) in the third sub-annular region (123) is 3 μm to 5 μm.

14. The product according to any one of claims 8 to 13, characterized in that The maximum width of the first through hole (221) of the light emitting diode device (200) in the central region (11) is 9 μm to 11 μm.

15. The product according to any one of claims 8 to 14, characterized in that The epitaxial layer (210) comprises a first light-emitting unit (211) and a second light-emitting unit (212), wherein the first light-emitting unit (211) and the second light-emitting unit (212) each comprise a first semiconductor layer (213), a multi-quantum well layer (214) and a second semiconductor layer (215) stacked in sequence, and the second semiconductor layer (215) each has a groove exposing the first semiconductor layer (213); The insulating layer (220) covers the first light-emitting unit (211) and the second light-emitting unit (212), and is located on the surface of the substrate (10); the insulating layer (220) has a first through hole (211) exposing the second semiconductor layer (215) of the first light-emitting unit (211) and the second semiconductor layer (215) of the second light-emitting unit (212), and a second through hole (212) exposing the groove of the first light-emitting unit (211) and the groove of the second light-emitting unit (212); The transparent conductive layer (230) is located on the two second semiconductor layers (215), and is connected to the two second semiconductor layers (215) through the two first through holes (221) respectively; The first semiconductor layer (213) of the first light-emitting unit (211) is electrically connected to the second semiconductor layer (215) of the second light-emitting unit (212).

16. The article according to claim 15, characterized in that The light emitting diode device (200) further comprises a connecting electrode (30), a first electrode (31) and a second electrode (32). The connecting electrode (30) is located on the insulating layer (220), and a first portion of the connecting electrode (30) is connected to the first semiconductor layer (213) of the first light-emitting unit (211) through the second through hole (222), and a second portion of the connecting electrode (30) is connected to the transparent conductive layer (230) of the second light-emitting unit (212); The first electrode (31) is located on the transparent conductive layer (230) of the first light-emitting unit (211), and the second electrode (32) is located in the groove of the second light-emitting unit (212) and is connected to the first semiconductor layer (213) through the second through hole (222).

17. The product according to claim 15 or 16, characterized in that The transparent conductive layer (230) comprises two conductive parts (230a), each of the conductive parts (230a) has a connected rectangular area (231) and a convex area (232), the convex area (232) is located on the long side of the rectangular area (231), one of the two conductive parts (230a) is located on the second semiconductor layer (215) of the first light-emitting unit (211), and the other of the two conductive parts (230a) is located on the second semiconductor layer (215) of the second light-emitting unit (212); The first light-emitting unit (211) and the second light-emitting unit (212) both have two grooves, the two grooves of the first light-emitting unit (211) are located on both sides of the raised area (232) corresponding to the first light-emitting unit (211), and the two grooves of the second light-emitting unit (212) are located on both sides of the raised area (232) corresponding to the second light-emitting unit.

18. The article according to claim 17, characterized in that The center of the first through hole (221) passes through the midline of the long side of the rectangular area (231), and passes through the midline of the perpendicular line between the side of the raised area (232) away from the rectangular area (231) and the long side of the rectangular area (231) away from the raised area (232).

19. The product according to claim 16 or 17, characterized in that The first light-emitting unit (211) has two first electrodes (31), and the two first electrodes (31) are symmetrically distributed on the transparent conductive layer (230); The second light-emitting unit (212) has two second electrodes (32), and the two second electrodes (32) are respectively located in two grooves of the second light-emitting unit (212) and are symmetrically arranged; The two first electrodes (31) and the two second electrodes (32) are symmetrically distributed.

20. A method for preparing a product, characterized in that: The preparation method comprises: Providing a substrate having a central region and an annular region, wherein the annular region surrounds the central region; forming a plurality of light-emitting diode devices on the substrate, each of the light-emitting diode devices comprising an epitaxial layer, an insulating layer and a transparent conductive layer sequentially stacked on the substrate, the insulating layer having a first through hole exposing the epitaxial layer, and the transparent conductive layer being connected to the epitaxial layer through the first through hole; Among them, a plurality of the light-emitting diode devices are arranged in the central area and the annular area, the area of ​​the contact surface between the first through hole of the light-emitting diode device in the central area and the epitaxial layer is larger than the area of ​​the contact surface between the first through hole of the light-emitting diode device in the annular area and the epitaxial layer, and the thickness of the transparent conductive layer of the light-emitting diode device in the central area is larger than the thickness of the transparent conductive layer of the light-emitting diode device in the annular area.

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