Patterned substrate and light emitting diode

Abstract

The invention discloses a patterned substrate and a light emitting diode. The patterned substrate comprises a first material layer and a second material layer. Wherein the second material layer comprises a plurality of pattern structures, and the plurality of pattern structures are arranged on the first surface of the first material layer at intervals. Hollow structures are contained in at least part of the graphic structures. Because the patterned substrate comprises the hollow structure, on one hand, the refractive index of air in the hollow structure is 1, the refractive index of the whole patterned substrate can be reduced, and the reflectivity of light rays of the patterned substrate reflected from the surface of the patterned structure to the direction far away from the patterned structure can be improved; and the light extraction efficiency of a subsequently formed light emitting diode is further improved. And on the other hand, as the graphic structure internally comprises a hollow structure, in the subsequent epitaxial epitaxy process, the stress for growing the epitaxial layer can be properly deformed and buffered, and the wafer warping is reduced, so that the epitaxial quality is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor devices, and in particular to a patterned substrate and a light emitting diode. Background Art

[0002] Light Emitting Diode is a semiconductor device that can directly convert electrical energy into light energy. It is a solid-state cold light source. The inherent physical properties of LED enable it to work at low voltage / current. It has the characteristics of high luminous efficiency, small size, long life, and energy saving. It is considered to be the best light source.

[0003] In order to obtain a higher quality and less dislocation density light-emitting diode epitaxial layer, sapphire substrates, silicon carbide substrates and silicon substrates are commonly used as growth carriers for light-emitting diode epitaxial layers in the prior art, among which sapphire substrates are the most widely used. In order to improve the light extraction efficiency of LEDs, a patterned substrate is often used as a substrate, that is, a pattern with a fine structure is made on the surface of a sapphire substrate, and then the LED material is epitaxially grown on the surface of such a patterned substrate. However, the existing patterned substrate structure is relatively simple and the light extraction efficiency is limited. How to further improve the light extraction efficiency of light-emitting diodes has become a technical difficulty in this field. Summary of the invention

[0004] In view of the above shortcomings of the prior art, an object of the present invention is to provide a patterned substrate and a light emitting diode to further improve the light extraction efficiency of the light emitting diode.

[0005] In order to achieve the above object and other related objects, the present invention provides a patterned substrate, comprising:

[0006] a first material layer;

[0007] The second material layer comprises a plurality of graphic structures, which are arranged at intervals on the first surface of the first material layer, and at least part of the graphic structures contain hollow structures.

[0008] According to one aspect of the present invention, there is also provided a light emitting diode, the light emitting diode comprising a patterned substrate, the patterned substrate being the patterned substrate described above;

[0009] The epitaxial structure is formed on a side of the patterned substrate having the patterned structure. The epitaxial structure includes a first semiconductor layer, an active layer and a second semiconductor layer in sequence from the side of the patterned substrate having the patterned structure.

[0010] Compared with the prior art, the patterned substrate and light-emitting diode of the present invention have at least the following beneficial effects:

[0011] The graphic substrate of the present invention comprises a first material layer and a second material layer. The second material layer comprises a plurality of graphic structures, and the plurality of graphic structures are arranged at intervals on the first surface of the first material layer. At least part of the graphic structures contain hollow structures. Thus, the graphic substrate of the present invention comprises a hollow structure. On the one hand, the refractive index of the air in the hollow structure is 1, which can reduce the refractive index of the entire graphic structure. When light is incident on the graphic substrate, since the graphic structure has a lower refractive index, most of the light can be reflected back from the surface of the graphic structure, thereby effectively improving the light extraction efficiency of the subsequently formed light-emitting diode. On the other hand, since the graphic structure contains a hollow structure, in the subsequent epitaxial epitaxial process, it can be appropriately deformed to buffer the stress of the growing epitaxial layer, reduce the wafer warping, and provide epitaxial growth quality.

[0012] The light emitting diode of the present invention includes the above-mentioned patterned substrate and also has the above-mentioned technical effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1a is a schematic structural diagram of a patterned substrate in an example of embodiment 1 of the present invention;

[0014] Figure 1b is a schematic structural diagram of a patterned substrate in another example of Embodiment 1 of the present invention;

[0015] Figure 2 A schematic structural diagram of a first material layer is provided in Example 1 of the present invention;

[0016] Figure 3 For Figure 2 A schematic structural diagram after a patterned first photoresist layer is formed on the first material layer in FIG.

[0017] Figure 4 Based on Figure 3 A schematic diagram of a top view of a substrate having a groove obtained after etching the patterned first photoresist layer;

[0018] Figure 5 For along Figure 4 Sectional view after cutting along A-A' direction;

[0019] Figure 6 For Figure 5 A schematic diagram of a structure after a second material layer is deposited on a substrate having a groove formed therein;

[0020] Figure 7 For Figure 6 A schematic diagram of a structure after a patterned second photoresist layer is formed on the patterned structure layer;

[0021] Figure 8 Based on Figure 7 A schematic diagram of the structure after the second patterned photoresist layer is etched;

[0022] Fig. 9 Schematic diagram of the structure of the light emitting diode in Example 2 of the present invention.

[0023] List of reference numerals:

[0024] 10 Patterned substrate

[0025] 100 First material layer

[0026] 101 Groove

[0027] 110 first photoresist layer

[0028] 102 First Surface

[0029] 200 Graphic Structure

[0030] 210 Second material layer

[0031] 220 second photoresist layer

[0032] 300 Hollow Structure

[0033] 20 Epitaxial structure

[0034] 21. First semiconductor layer

[0035] 22 Active layer

[0036] 23. Second semiconductor layer

[0037] 31. First electrode

[0038] 32. Second electrode DETAILED DESCRIPTION

[0039] The following specific embodiments illustrate the embodiments of the present invention, and those familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0040] It should be noted that the diagrams provided in the embodiments of the present invention are only used to illustrate the basic concept of the present invention in a schematic manner. Although the diagrams only show the components related to the present invention rather than being drawn according to the number, shape and size of the components in actual implementation, the form, quantity and proportion of each component can be changed at will during actual implementation, and the layout of the components may also be more complex. The structures, proportions, sizes, etc. illustrated in the drawings of the specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions that can be implemented in this application, so they have no technical substantive significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the effects and purposes that can be achieved by the present invention.

[0041] Patterned substrates currently include two types: single crystal substrates and composite substrates. Regardless of whether it is a single crystal substrate or a composite substrate, the refractive index of the pattern material of the patterned substrate is greater than 1. The inventors have found through simulation and experimental verification that the lower the refractive index of the pattern material of the patterned substrate, the easier it is for the light irradiated on the substrate to be totally reflected, thereby improving the light extraction efficiency.

[0042] In order to further improve the light extraction efficiency of the light emitting diode, this embodiment provides a patterned substrate, which includes:

[0043] a first material layer;

[0044] The second material layer includes a plurality of graphic structures, and the plurality of graphic structures are arranged at intervals on the first surface of the first material layer, and at least part of the graphic structures contain hollow structures. Therefore, the graphic substrate in the present invention includes a hollow structure. On the one hand, the refractive index of the air in the hollow structure is 1, and the outside and inside of the hollow structure have a large refractive index change, which can enhance the total reflection effect, thereby improving the reflectivity of the light incident on the graphic substrate reflected back by the surface of the graphic structure, which is beneficial to the light extraction efficiency of the subsequently formed light-emitting diode. On the other hand, since the graphic structure contains a hollow structure, in the subsequent epitaxial epitaxial process, it can be appropriately deformed to buffer the stress of the growing epitaxial layer, reduce the wafer warping, and make the epitaxy quality higher.

[0045] Optionally, the patterned substrate further comprises:

[0046] A plurality of grooves are arranged at intervals on the first surface of the first material layer, and the pattern structure fills the grooves one by one, covering a portion of the first surface of the first material layer connected to the grooves. Since the first material layer in this embodiment includes grooves, the sidewalls of the grooves can increase the reflection area and the reflection angle of the light, so that more light can be reflected back to the pattern structure, reducing the loss of light inside the pattern, and further improving the light extraction efficiency.

[0047] Optionally, the bottom of the hollow structure is lower than the first surface of the first material layer.

[0048] Optionally, the volume of each hollow structure occupies 10% to 35% of the volume of the corresponding graphic structure. The setting of the volume of the hollow structure maximizes the interface between the hollow structure and the graphic structure, increases the reflection area of ​​total reflection, and is conducive to further improving the light extraction efficiency.

[0049] Optionally, a cross-sectional area of ​​a side of the hollow structure close to the first material layer is larger than a cross-sectional area of ​​a side away from the first material layer.

[0050] Optionally, all boundaries of each hollow structure are covered by the corresponding graphic structure. Therefore, since the refractive index of the material of the graphic structure is lower than the reflectivity of the material of the first material layer, the light of different incident angles partially reflected or refracted to the graphic structure on the surface of the first material layer can also be reflected as much as possible, thereby reducing the light emitted through the first material layer.

[0051] Optionally, there is a spacing between adjacent graphic structures, and the size of the spacing is between 0.05 μm and 0.5 μm. The setting of the spacing can provide a growth area for epitaxial growth, which is beneficial to the quality of epitaxial growth.

[0052] Optionally, along a first surface direction parallel to the first material layer, a bottom opening size of the groove is between 0.6 μm and 2 μm.

[0053] Optionally, along a direction perpendicular to the first surface of the first material layer, a depth of the groove is between 0.5 μm and 1.5 μm.

[0054] Optionally, the material of the first material layer is the same as the material of the graphic structure; or the material of the first material layer is different from the material of the graphic structure.

[0055] This embodiment also provides a light emitting diode, including:

[0056] A patterned substrate, wherein the patterned substrate is the above-mentioned patterned substrate;

[0057] An epitaxial structure is formed on a side of a patterned substrate having a patterned structure, and the epitaxial structure includes a first semiconductor layer, an active layer, and a second semiconductor layer in sequence from the side of the patterned substrate having a patterned structure. Since the light-emitting diode includes the above-mentioned patterned substrate, the arrangement of the hollow structure in the patterned substrate can totally reflect most of the light emitted from the epitaxial layer, thereby improving the light extraction efficiency. Optionally, a groove is also arranged on the first material layer of the patterned substrate, and the groove can also increase the reflection area and reflection angle of the light, further increase the reflection of the incident light, and improve the light extraction efficiency. In addition, the arrangement of the hollow structure in the patterned substrate can also buffer the stress of the epitaxial layer formed on the patterned structure, thereby improving the quality of the grown epitaxial layer and the reliability of the light-emitting diode.

[0058] The present invention is described in detail below with reference to specific embodiments.

[0059] Example 1

[0060] This embodiment provides a patterned substrate, referring to Figure 1a Or 1b, the patterned substrate 10 includes a first material layer 100 and a second material layer, and the second material layer includes a plurality of pattern structures 200. Among them, the plurality of pattern structures 200 are arranged at intervals on the first surface 102 of the first material layer 100, and at least part of the pattern structures 200 contain hollow structures. Therefore, the patterned substrate 10 in this embodiment includes a hollow structure 300. On the one hand, the refractive index of the air in the hollow structure 300 is 1, and the external material of the hollow structure 300 and the internal (air) have a large refractive index difference, which can enhance the total reflection effect and thus the light incident on the patterned substrate 10 can be reflected back as much as possible from the surface of the pattern structure 200, avoiding the light from being emitted from the first material layer 100, which is beneficial to the light extraction efficiency of the subsequently formed light-emitting diode. On the other hand, since the pattern structure 200 contains a hollow structure 300, in the subsequent epitaxial epitaxial process, it can be appropriately deformed to buffer the stress of the growing epitaxial layer, reduce the wafer warping, and make the epitaxial quality higher.

[0061] Specifically, the first material layer 100 includes one of sapphire, SiC, Si, GaN, AlN or ZnO, and this embodiment is described by taking a sapphire substrate as an example. The refractive index of the sapphire substrate is 1.7.

[0062] Reference Figure 1a Or 1b, a plurality of graphic structures 200 are arranged at intervals on the surface of the first material layer 100. The shape of the graphic structure 200 can be any shape, and this embodiment does not limit the shape of the graphic structure 200. For example, the graphic structure 200 can be conical, cylindrical, hemispherical, truncated cone, or polygonal cone.

[0063] The cross-sectional width D1 of the side of the graphic structure 200 close to the first material layer 100 is between 2 μm and 4 μm, and there is a spacing D2 between adjacent graphic structures 200, and the size of the spacing D2 is between 0.05 μm and 0.5 μm. The purpose of setting the spacing is to perform epitaxial growth and improve the quality of epitaxial growth. Optionally, the material of the graphic structure 200 is Al 2 O 3 、SiO 2 、Si 3 N 4 、ZnO 2 、Si、SiC、GaAs、Ti 3 O 5 or TiO 2 One of a kind.

[0064] Reference Figure 1a Or 1b, a plurality of hollow structures 300 are arranged in a one-to-one correspondence in the pattern structure 200, and at least part of the boundary of the hollow structure 300 is covered by the material of the pattern structure 200. Thus, when light is incident from the side of the patterned substrate 10 having the pattern structure 200, the light is incident from the pattern structure 200 with a larger refractive index to the air in the hollow structure 300. Since the refractive index of the air is 1, the light is incident from the medium with a larger refractive index to the medium with a smaller refractive index, and total reflection occurs, so that most of the incident light is emitted from the side of the patterned substrate 100 having the pattern structure 200, thereby preventing the light from emitting through the first material layer 100. Optionally, the shape of the hollow structure 300 can be arbitrary, for example, it can be an irregular structure formed based on the control of the formation process. Optionally, refer to Figure 1a Alternatively, 1b, the hollow structure 300 is formed such that the cross-sectional area of ​​the side close to the first material layer 100 is larger than the cross-sectional area of ​​the side away from the first material layer 100, that is, a structure that is narrow at the top and wide at the bottom. Optionally, the volume of the hollow structure 300 occupies 10 to 35% of the volume of the graphic structure 200. The volume of the hollow structure 300 is relatively large, that is, its boundary size is relatively large, which can increase the interface where total reflection occurs, thereby further increasing the total reflection of light. Optionally, the bottom of the hollow structure 300 is lower than the surface of the first material layer 100, which can increase the interface area of ​​the hollow structure 300 and improve the reflection efficiency of light.

[0065] The material of the first material layer 100 and the material of the pattern structure 200 may be the same, for example, both are sapphire, or may be different, for example, the material of the first material layer 100 is sapphire and the material of the pattern structure 200 is silicon dioxide.

[0066] In one example of this embodiment, Figure 1aAs shown, the material of the graphic structure 200 is the same as that of the first material layer 100, both of which are sapphire. Optionally, the height H1 of the graphic structure 200 is 0.5 μm to 1.5 μm. In this embodiment, since the first material layer 100 is made of the same material as the graphic structure 200, it can also be regarded that the hollow structure 300 is partially located in the graphic structure 200 and partially located in the first material layer 100. The bottom of the hollow structure 300 is lower than the first surface 102 of the first material layer 100. The volume of the hollow structure 300 trapped in the first material layer 100 occupies more than 1 / 5 of the volume of the entire hollow structure 300. The hollow structure 300 trapped in the first material layer 100 is as shown in FIG. Figure 1a As shown in the dotted oval box.

[0067] In this embodiment, the portion of the pattern structure 200 is higher than the first surface 102 (including the portion of the hollow structure 300 higher than the first surface 102). Figure 1a As shown by the middle shaded area, in this embodiment, the complete hollow structure 300 occupies 10-35% of the volume of the graphic structure 200 (shaded area).

[0068] In another example of this embodiment, referring to Figure 1b , the materials of the first material layer 100 and the graphic structure 200 are different. At this time, a number of grooves 101 are also arranged at intervals on the first material layer 100. At this time, the first surface 102, the sidewalls of the groove 101, and the surface of the groove 101 are all boundaries of the first material layer, the first surface 102 is higher than the surface of the groove 101, and the sidewalls of the groove connect the first surface 102 and the surface of the groove 101. The graphic structure 200 fills the groove 101 one by one, and covers the first surface 102 of the first material layer 100 that is partially located at the periphery of the groove 101. In this embodiment, the graphic structure 200 can be regarded as two parts, the part above the first surface 102 is conical, and the part below the first surface 102 is consistent with the shape of the groove 101. The part of the graphic structure 200 is as follows Figure 1bAs shown in the middle shade (including the complete hollow structure 300). Since in this example, the first material layer 100 and the graphic structure 200 are made of different materials, the two have different refractive indices, which is conducive to the reflection of light, and the first material layer 100 includes a groove 101, the side wall of the groove 101 can increase the reflection area and light reflection angle of the light, so that more light can be reflected back to the graphic structure 200, reducing the loss of light inside the graphic, and further improving the light extraction efficiency. Optionally, the bottom opening size of the groove 101 is smaller than the top opening size. For example, the opening size of the groove 101 gradually increases from the bottom to the top. In this embodiment, along the direction parallel to the first surface 102 of the first material layer 100, the opening size D3 of the groove 101 is between 0.6μm and 2μm. Along the direction perpendicular to the first surface 102 of the first material layer 100, the depth H2 of the groove 101 is between 0.5μm and 1.5μm. At this time, the graphic structure 200 includes a portion filled in the groove 101 and a portion formed above the groove 101. The hollow structure 300 has a portion located in the groove 101, such as Figure 1b The portion framed by the dotted ellipse, and the volume of the portion of the hollow structure 300 formed in the groove 101 occupies more than 1 / 5 of the volume of the entire hollow structure 300. In this example, the material of the first material layer 100 is sapphire, and the material of the graphic structure 200 is silicon dioxide. The height H1 of the graphic structure 200 is 1 μm to 3 μm.

[0069] Optionally, the side of the hollow structure 300 close to the first material layer 100 is directly in contact with the first material layer 100, and the boundaries of the remaining hollow structures 300 are covered by the graphic structure 200, so that no matter whether the light is incident from any position on the side with the graphic structure 200, it is incident from the graphic structure 200 to the hollow structure 300, that is, total reflection will occur, which is beneficial to the light extraction efficiency. In this embodiment, all boundaries of the hollow structure 300 are covered by the corresponding graphic structure 200. Generally, light with different incident angles that is partially reflected or refracted to the surface of the first material layer 100 can also be reflected. Since the material of the graphic structure 200 in this embodiment is silicon dioxide, the refractive index of silicon dioxide at the bottom of the hollow structure 300 is less than the refractive index of the sapphire first material layer, which is more conducive to the reflection of the incident light and improves the reflectivity of light.

[0070] The patterned substrate 10 in the above examples can be obtained by the following preparation method:

[0071] S1: providing a first material layer, and forming grooves arranged at intervals on the first material layer;

[0072] Specifically, refer to Figure 2, providing a first material layer 100, the first material layer 100 is a sapphire substrate, and the first material layer 100 is a planar substrate, and its surface has no pattern structure. Figure 3 , a first photoresist layer 110 is formed by spin coating on the surface of the first material layer 100, and the first photoresist layer 110 is a negative photoresist layer. The first photoresist layer 110 is patterned by photolithography and development, so that a plurality of groove areas arranged at intervals are exposed on the surface of the first material layer 100. Based on the groove areas exposed by etching the patterned first photoresist layer 110, a method such as dry etching can be used to form grooves 101, such as Figure 4 Or as shown in 5.

[0073] S2: depositing a second material layer on the surface of the first material layer having the groove;

[0074] Specifically, based on step S1, refer to Figure 5 and 6 , a second material layer 210 is deposited on the surface of the first material layer 100 having the groove 101. For example, a silicon dioxide optical film can be formed by chemical vapor deposition. The thickness of the silicon dioxide optical film can be 2 μm to 5 μm. Since the surface of the first material layer 100 has the groove 101, the deposition rate at the corner of the end of the groove 101 is greater than the deposition rate at other positions. As the deposition thickness increases, the deposition thickness at the corner of the end of the groove 101 gradually increases in the horizontal and vertical directions. The silicon dioxide at the corner of the port eventually forms a closure at a certain position, that is, a closed hollow structure 300 is formed in the graphic structure 200 corresponding to the position of the groove 101, such as Figure 6 shown.

[0075] S3: forming a patterned second photoresist layer on the pattern structure layer;

[0076] Specifically, refer to Figure 7 , a second photoresist layer 220 is formed on the second material layer 210, and the second photoresist layer 220 is patterned. Similarly, when the photoresist layer is patterned, a photolithography plus development method is adopted. In the present embodiment, the second photoresist layer 220 is a positive photoresist layer. The patterned second photoresist layer 220 is formed on the second material layer 210, and corresponds to the position of the hollow structure 300 in the second material layer 210, exposing the surface area of ​​the second material layer 210 above the adjacent hollow structures 300.

[0077] S4: etching the pattern structure layer based on the patterned second photoresist layer to form a pattern structure above the first material layer.

[0078] Specifically, continue to refer to Figure 7Based on the patterned second photoresist layer 220, the exposed surface area of ​​the second material layer 210 is etched to form a pattern structure 200 above the first material layer 100. For example, the exposed second material layer 210 can be etched by dry etching, so that a hollow structure 300 is formed in each of the formed pattern structures 200, and finally a structure such as Figure 8 shown.

[0079] Example 2

[0080] This embodiment provides a light emitting diode, referring to Fig. 9 The light emitting diode comprises a patterned substrate 10 and an epitaxial structure 20 formed on one side of the patterned substrate 10 having a patterned structure 200. The patterned substrate is the patterned substrate in Example 1, and the epitaxial structure 20 comprises a first semiconductor layer 21, an active layer 22, and a second semiconductor layer 23 in sequence from one side of the patterned substrate 10 having the patterned structure 200.

[0081] Specifically, refer to Fig. 9 , providing the patterned substrate in Example 1, and sequentially forming an epitaxial structure 20 consisting of a first semiconductor layer 21, an active layer 22, and a second semiconductor layer 23 of opposite type to the first semiconductor layer 21 on a side of the patterned substrate 10 having the patterned structure 200. Optionally, etching is performed downward from the surface of the second semiconductor layer 23 until the first semiconductor layer 21 is exposed. A first electrode 31 is formed on the exposed first semiconductor layer 21, so that the first electrode 31 is electrically connected to the first semiconductor layer 21. A second electrode 32 is formed on the second semiconductor layer 23, so that the second electrode 32 is electrically connected to the second semiconductor layer 23. Optionally, a transparent conductive layer (ITO) or an ohmic contact layer is also formed on the first semiconductor layer 21 and the second semiconductor layer 23. The first electrode 31 and / or the second electrode 32 are formed on the transparent conductive layer or the ohmic contact layer. Optionally, other structural layers are formed between the first electrode 31 and the first semiconductor layer 21, and between the second electrode 32 and the second semiconductor layer 23. The structural layer settings are all common structures in the prior art and are not described in detail here. Optionally, the first semiconductor layer 21 may be an N-type gallium nitride layer, and the second semiconductor layer 23 may be a P-type gallium nitride layer.

[0082] The light emitting diode in this embodiment includes the above-mentioned patterned substrate, and the hollow structure in the patterned substrate can fully reflect most of the light emitted from the epitaxial layer, thereby improving the light extraction efficiency. The patterned substrate is also provided with grooves, which can also increase the reflection area and reflection angle of the light, further increase the reflection of the incident light, and improve the light extraction efficiency. In addition, the hollow structure in the patterned substrate can also buffer the stress of the epitaxial layer formed on the patterned structure, thereby improving the quality of the grown epitaxial layer and the reliability of the light emitting diode.

[0083] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A patterned substrate, characterized in that: include: a first material layer; The second material layer comprises a plurality of graphic structures, wherein the plurality of graphic structures are arranged at intervals on the first surface of the first material layer, and at least part of the graphic structures contain hollow structures.

2. The patterned substrate according to claim 1, characterized in that The patterned substrate further comprises: A plurality of grooves are arranged at intervals on the first surface of the first material layer, and the graphic structure fills the grooves one by one and covers a portion of the first surface of the first material layer connected to the grooves.

3. The patterned substrate according to claim 1, characterized in that The bottom of the hollow structure is lower than the first surface of the first material layer.

4. The patterned substrate according to claim 1, characterized in that The volume of each hollow structure occupies 10% to 35% of the volume of the corresponding graphic structure.

5. The patterned substrate according to claim 1, characterized in that The cross-sectional area of ​​the hollow structure at a side close to the bottom of the first material layer is larger than the cross-sectional area of ​​the hollow structure at a side away from the bottom of the first material layer.

6. The patterned substrate according to claim 1, characterized in that All boundaries of each hollow structure are covered by the corresponding graphic structure.

7. The patterned substrate according to claim 1, characterized in that: There is a gap between adjacent graphic structures, and the size of the gap is between 0.05 μm and 0.5 μm.

8. The patterned substrate according to claim 2, characterized in that Along a first surface direction parallel to the first material layer, a bottom opening size of the groove is between 0.6 μm and 2 μm.

9. The patterned substrate according to claim 2, characterized in that: Along a direction perpendicular to the first surface of the first material layer, a depth of the groove is between 0.5 μm and 1.5 μm.

10. The patterned substrate according to claim 1, characterized in that The material of the first material layer is the same as that of the second material layer; or the material of the first material layer is different from that of the second material layer.

11. A light emitting diode, characterized in that: include: A patterned substrate, wherein the patterned substrate is the patterned substrate according to any one of claims 1 to 10; The epitaxial structure is formed on the side of the patterned substrate having the patterned structure, and the epitaxial structure includes a first semiconductor layer, an active layer and a second semiconductor layer in sequence from the side of the patterned substrate having the patterned structure.

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