LED structure and manufacturing method thereof

Abstract

The invention discloses an LED structure and a manufacturing method thereof, the LED structure comprises a substrate, one side of the substrate is provided with a plurality of grooves, the substrate among the plurality of grooves is provided with a first insulating layer, each groove at least comprises an epitaxial side wall, and in the same groove, the area of the epitaxial side wall is larger than the maximum opening area of the groove; and a plurality of LED light-emitting units, wherein each LED light-emitting unit is located on at least one epitaxial side wall of the groove. The current density of the LED structure can be reduced, the LED structure is prevented from generating more heat, and the display effect of the LED structure is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to an LED structure and a manufacturing method thereof. Background Art

[0002] In the prior art, a high current density is often required to achieve high brightness, but the LED light-emitting unit is easily burned out under a high current density, and the high current density is not conducive to the display effect of the LED structure composed of the LED light-emitting units. Summary of the invention

[0003] The present invention provides an LED structure, which can reduce current density and improve the display effect of the LED structure.

[0004] According to one aspect of the present invention, there is provided an LED structure, comprising:

[0005] A substrate having a plurality of grooves disposed on one side of the substrate, and a first insulating layer disposed on the substrate between the plurality of grooves, wherein each groove includes at least one epitaxial sidewall, and within the same groove, the area of ​​the epitaxial sidewall is greater than the maximum opening area of ​​the groove;

[0006] A plurality of LED light-emitting units are provided, each of which is located on at least one outer side wall of the groove.

[0007] According to another aspect of the present invention, there is provided a method for manufacturing an LED structure, comprising:

[0008] Providing a substrate, and manufacturing a first insulating layer having a plurality of patterns on the substrate;

[0009] Using the first insulating layer as a mask, etching the substrate to form grooves, wherein each groove includes at least one epitaxial sidewall, and within the same groove, the area of ​​the epitaxial sidewall is larger than the maximum opening area of ​​the groove;

[0010] An LED light-emitting unit is epitaxially manufactured on at least one epitaxial side wall of the groove.

[0011] The LED structure provided by the technical solution of the embodiment of the present invention includes: a substrate, a plurality of grooves are arranged on one side of the substrate, a first insulating layer is arranged on the substrate between the plurality of grooves, wherein each groove includes at least one epitaxial sidewall, and in the same groove, the area of ​​the epitaxial sidewall is larger than the maximum opening area of ​​the groove; and a plurality of LED light-emitting units, each of which is located on at least one epitaxial sidewall of the groove. Since the area of ​​the epitaxial sidewall of the same groove is larger than the maximum opening area of ​​the groove, the area of ​​the LED light-emitting unit grown on the epitaxial sidewall is larger and the current density is lower under the same current density, thereby reducing the current density of the LED structure and improving the display effect of the LED structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, 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 invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0013] Figure 1 It is a structural schematic diagram of an LED structure provided in Embodiment 1 of the present invention.

[0014] Figure 2 This is a structural schematic diagram of another LED structure provided in the first embodiment of the present invention.

[0015] Figure 3 This is a structural schematic diagram of another LED structure provided in the first embodiment of the present invention.

[0016] Figure 4 This is a structural schematic diagram of another LED structure provided in the first embodiment of the present invention.

[0017] Figure 5 It is a schematic diagram of the three-dimensional structure of a substrate provided in Example 1 of the present invention.

[0018] Figure 6 It is a schematic diagram of the three-dimensional structure of another substrate provided in the first embodiment of the present invention.

[0019] Figure 7 It is a top view of a LED structure provided in the first embodiment of the present invention.

[0020] Figure 8 This is a top view of another LED structure provided in the first embodiment of the present invention.

[0021] Fig. 9 yes Figure 7 A schematic cross-sectional view of an LED structure along section line AA.

[0022] Fig.10 This is a top view of another LED structure provided in the first embodiment of the present invention.

[0023] Fig.11 This is a structural schematic diagram of another LED structure provided in the first embodiment of the present invention.

[0024] Fig.12 This is a structural schematic diagram of another LED structure provided in the first embodiment of the present invention.

[0025] Fig.13 This is a structural schematic diagram of another LED structure provided in the first embodiment of the present invention.

[0026] Fig.14 This is a structural schematic diagram of another LED structure provided in the first embodiment of the present invention.

[0027] Fig.15 This is a structural schematic diagram of another LED structure provided in the first embodiment of the present invention.

[0028] Fig.16 This is a top view of another LED structure provided in the first embodiment of the present invention.

[0029] Fig.17 This is a flow chart of a method for manufacturing an LED structure provided in the second embodiment of the present invention. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0031] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0032] Embodiment 1

[0033] An embodiment of the present invention provides an LED structure. Figure 1 is a schematic diagram of an LED structure provided by Embodiment 1 of the present invention, Figure 2It is a structural schematic diagram of another LED structure provided in Embodiment 1 of the present invention; the LED structure comprises: a substrate 10, a plurality of grooves 11 are arranged on one side of the substrate 10, a first insulating layer 40 is arranged on the substrate 10 between the plurality of grooves 11, wherein each groove 11 comprises at least one epitaxial side wall A1, and within the same groove 11, the area of ​​the epitaxial side wall A1 is larger than the maximum opening area of ​​the groove 11; a plurality of LED light-emitting units 20, each LED light-emitting unit 20 is located on at least one epitaxial side wall A1 of the groove 11.

[0034] The substrate 10 may be a composite substrate or a silicon substrate on which a silicon layer 13 is fabricated on an insulating substrate 12; the material of the first insulating layer 40 may be silicon dioxide, silicon nitride or other mask materials; the first insulating layer 40 has a plurality of openings, and the groove 11 is fabricated using the opening of the first insulating layer 40 as a mask; the shape of the opening of the groove 11 and the bottom surface of the groove 11 may be consistent, and the area of ​​the opening is greater than or equal to the area of ​​the bottom surface of the groove 11, and the groove 11 may be formed by the groove 11. Figure 1 , when the area of ​​the quadrilateral of the opening is equal to the area of ​​the bottom quadrilateral of the groove 11, the cross-sectional shape of the groove 11 is a rectangle in the direction perpendicular to the plane where the substrate 10 is located; Figure 2 , when the area of ​​the opening quadrilateral is larger than the area of ​​the bottom quadrilateral of the groove 11, the cross-sectional shape of the groove 11 is an inverted trapezoid. Each LED light-emitting unit 20 is located on at least one epitaxial side wall of the groove 11. Exemplarily, one LED light-emitting unit 20 is respectively arranged on each epitaxial side wall of each groove 11; or, one LED light-emitting unit 20 is arranged on multiple epitaxial side walls of each groove 11; or, multiple epitaxial side walls of each groove 11 have different areas, and LED light-emitting units 20 emitting light of different colors are arranged on multiple epitaxial side walls of each groove 11. Since the area of ​​the epitaxial side wall in the same groove 11 is larger than the maximum opening area of ​​the groove 11, under the condition of inputting the same current signal, the area of ​​the LED light-emitting unit 20 grown on the epitaxial side wall is larger and the current density is lower, thereby avoiding the LED structure from generating more heat and improving the display effect of the LED structure.

[0035] Optional, reference Figure 1 and Figure 2 The substrate 10 is a composite substrate on which a silicon layer 13 is fabricated on an insulating substrate 12. The groove 11 penetrates the silicon layer 13. The epitaxial sidewall A1 is Si <111> Crystal direction.

[0036] The groove 11 penetrates the silicon layer 13, and the epitaxial sidewall A1 of the groove is Si <111> The LED light emitting unit 20 can be grown on the epitaxial side wall A1 of the groove, thereby avoiding large-area lattice defects in the LED light emitting unit 20.

[0037] Optionally, the insulating substrate 12 is made of a transparent material so that the light is emitted from a side of the insulating substrate 12 away from the silicon layer 13 .

[0038] Optionally, the substrate 10 is a SOI (Silicon On Insulator) substrate, the insulating substrate 12 is silicon dioxide, and is located between the silicon layer 13 and another silicon layer.

[0039] Optional, Figure 3 is a structural schematic diagram of another LED structure provided in the first embodiment of the present invention, Figure 4 is a schematic diagram of another LED structure provided in the first embodiment of the present invention, referring to Figure 3 and Figure 4 The substrate 10 is a silicon substrate, the groove 11 is located on one side of the silicon substrate, and the epitaxial sidewall A1 is Si <111> The LED structure further includes a second insulating layer 80, and the second insulating layer 80 is located at least on the bottom surface of the groove 11.

[0040] The material of the second insulating layer 80 may be silicon dioxide, silicon nitride or other insulating materials, which can ensure that the subsequent electrodes can be electrically connected to the LED light-emitting unit 20 and play a role in insulation protection.

[0041] Optional, reference Figure 3 and Figure 4 The second insulating layer 80 is also located on the surface of the first insulating layer 40 away from the substrate 10 .

[0042] Optional, Figure 5 is a schematic diagram of a three-dimensional structure of a substrate provided in Example 1 of the present invention, with reference to Figure 2 , Figure 4 and Figure 5 , Figure 2 and Figure 4 The LED light-emitting unit provided in Figure 5 On the epitaxial side wall A1 of the substrate along the section line BB, the surface of the substrate 10 close to the first insulating layer 40 is Si <100> When the crystal orientation is 90°, the angle between the epitaxial side wall A1 and the bottom surface of the groove 11 is greater than 90°, and the cross-sectional shape of the groove 11 is an inverted trapezoid.

[0043] Optional, Figure 6 is a schematic diagram of a three-dimensional structure of another substrate provided in the first embodiment of the present invention, with reference to Figure 1 , Figure 3 and Figure 6 , Figure 1 and Figure 3 The LED light-emitting unit provided in Figure 6On the epitaxial sidewall of the substrate along the section line CC, the surface of the substrate 10 close to the first insulating layer 40 is Si <110> When the crystal direction is oriented, the angle between the epitaxial side wall A1 and the bottom surface of the groove 11 is greater than 90°; or, the LED light-emitting unit is made in Figure 6 On the epitaxial side wall A1 of the middle substrate along the section line DD, the angle between the epitaxial side wall A1 and the bottom surface of the groove 11 is 90°.

[0044] It should be noted that the reference Figure 5 The surface of the substrate 10 close to the first insulating layer 40 is Si <100> In the crystal orientation, one groove 11 includes four epitaxial side walls A1, and the angle between the epitaxial side walls A1 and the bottom surface of the groove 11 is greater than 90°.

[0045] It should be noted that the surface of the substrate 10 close to the first insulating layer 40 is Si <110> When the crystal orientation is , a groove 11 may include six epitaxial sidewalls, wherein four epitaxial sidewalls are perpendicular to the bottom surface of the groove 11, and two epitaxial sidewalls are opposite to each other and the angle between them and the bottom surface of the groove 11 is greater than 90° (not shown); or, referring to Figure 6 A groove 11 includes four epitaxial side walls, wherein two epitaxial side walls are opposite to each other and perpendicular to the bottom surface of the groove 11 , and the two epitaxial side walls are opposite to each other and the angle between them and the bottom surface of the groove 11 is >90°.

[0046] Among them, when the angle between the epitaxial side wall and the bottom surface of the groove 11 is greater than 90°, the groove forms a bowl-shaped structure with a larger light outlet area, which is conducive to reflecting more light and improving the light output efficiency.

[0047] It should be noted that the reference Figures 1 to 6 The LED light-emitting unit 20 is grown on the epitaxial sidewall made of silicon material, wherein the silicon material serves as the epitaxial growth site, and because the silicon material is opaque, the sidewall can directly form a retaining wall structure to block the light crosstalk between the two grooves 11, thereby simplifying the process of later manufacturing the retaining wall structure.

[0048] Optional, Figure 7 is a top view of an LED structure provided by Embodiment 1 of the present invention, Figure 8 is a top view of another LED structure provided in the first embodiment of the present invention. Fig. 9 yes Figure 7 A schematic cross-sectional view of an LED structure along the section line AA, see Figures 7 to 9 The LED light emitting unit 20 includes a buffer layer 21, a first semiconductor layer 22, an active layer 23 and a second semiconductor layer 24 which are stacked in sequence.

[0049] The buffer layer 21 has n-type doping, which can improve the crystal growth quality of the first semiconductor layer 22. Exemplarily, the first semiconductor layer 22 can be an n-type semiconductor layer, the second semiconductor layer 24 can be a p-type semiconductor layer, the active layer 23 can be a light-emitting layer, and the active layer 23 can be a blue light-emitting layer, a red light-emitting layer, or a green light-emitting layer.

[0050] Optional, reference Fig. 9 , the first semiconductor layer 22 covers the buffer layer 21, the active layer 23 covers the first semiconductor layer 22, the second semiconductor layer 24 covers the active layer 23, and the second semiconductor layer 24 is not in electrical contact with the substrate 10. Optionally, a nucleation layer (not shown in the figure) is also included between the epitaxial sidewall and the buffer layer 21. Specifically, the above-mentioned layer-by-layer structure is formed by lateral epitaxy of the semiconductor material, and one end of the first semiconductor layer 22, the active layer 23 and the second semiconductor layer 24 are all in contact with the first insulating layer 40 or the second insulating layer 80, which not only avoids the contact short circuit between the first semiconductor layer 22 and the second semiconductor layer 24, but also facilitates the later production of electrodes electrically connected to the second semiconductor layer 24.

[0051] Optionally, the material of the LED structure includes any one of GaN-based materials, GaAs-based materials and InP-based materials or a combination thereof.

[0052] Optionally, the LED structure further includes a DBR layer, which is located between the LED light-emitting unit and the epitaxial sidewall, and the material of the DBR layer is a semiconductor material. Specifically, along the direction of the epitaxial sidewall pointing to the LED light-emitting unit, the LED light-emitting unit includes a first semiconductor layer, an active layer, and a second semiconductor layer stacked in sequence, and the DBR layer is located between the first semiconductor layer and the epitaxial sidewall, which can avoid the substrate material from absorbing the light and reflect the light emitted by the active layer; Optionally, the LED structure also includes a buffer layer and a nucleation layer located between the first semiconductor layer and the epitaxial sidewall, and the positional relationship between the DBR layer, the buffer layer, and the nucleation layer is not limited. Optionally, when the material of the LED structure is a GaN-based material, the DBR layer is composed of a GaN layer and a porous GaN layer.

[0053] Optional, reference Figure 7 The LED structure further includes a third insulating layer 90 located at the angle formed by two adjacent epitaxial sidewalls. The third insulating layer 90 allows the same groove 11 to include multiple independently controllable LED light-emitting units 20. The material of the third insulating layer 90 can be the same as that of the first insulating layer 40 or the second insulating layer 80, which will not be described in detail here. Specifically, Figure 7 Only one recess including four epitaxial side walls is illustrated.

[0054] Optionally, the opening shape of the groove 11 includes any one of a triangle, a quadrilateral, and a hexagon. It should be noted that, unless otherwise specified, the following embodiments all take the opening shape of the groove 11 as a quadrilateral as an example. Specifically, when the opening shape of the groove 11 is a triangle, one groove includes only one extension side wall, corresponding to one LED light-emitting unit; when the opening shape of the groove 11 is a quadrilateral, one groove may include four extension side walls, corresponding to four LED light-emitting units; when the opening shape of the groove 11 is a hexagon, one groove may include six extension side walls, corresponding to six LED light-emitting units.

[0055] Optional, reference Figure 8 The buffer layer 21, the first semiconductor layer 22, the active layer 23 and the second semiconductor layer 24 form an annular structure surrounding the inner circle of the groove 11. An electrical signal is transmitted to the first semiconductor layer 22 of the annular structure, and an electrical signal is transmitted to the second semiconductor layer 24 of the annular structure, and the active layer 23 on different side walls is controlled at the same time.

[0056] Optional, Fig.10 is a top view of another LED structure provided in the first embodiment of the present invention, referring to Fig.10 The third insulating layer 90 only isolates the buffer layer 21, the first semiconductor layer 22 and the active layer 23 of the adjacent epitaxial sidewalls in the same groove 11, and the second semiconductor layers 24 at the four epitaxial sidewalls form a ring structure surrounding the inner circle of the groove 11. The second semiconductor layer 24 of the ring structure shares one electrical signal and transmits another electrical signal to the four first semiconductor layers 22 in the same groove 11. Therefore, the active layer 23 in the same groove 11 can be independently controlled.

[0057] It should be noted that the electrical signal may be a current magnitude, a voltage magnitude or a switch signal.

[0058] It should be noted that the area of ​​the epitaxial side wall is the four side walls of the same groove 11 minus the area covered by the third insulating layer 90, that is, the effective side wall area used to grow the LED light-emitting unit 20. The effective side wall area is larger than the maximum opening area of ​​the groove 11. Under the condition of inputting the same current signal, the current density can be reduced, thereby avoiding the LED structure from generating too much heat and improving the display effect of the LED structure.

[0059] Optional, Fig.11 is a schematic diagram of another LED structure provided in the first embodiment of the present invention, referring to Fig.11 The LED structure further includes: a first electrode 60 , and the first electrode 60 is electrically connected to the second semiconductor layer 24 .

[0060] Optional, reference Fig.11The LED structure further includes: a current spreading layer 50 , which is located on a side of the first insulating layer 40 away from the substrate 10 , wherein the current spreading layer 50 contacts the second semiconductor layer 24 , and the first electrode 60 is electrically connected to the second semiconductor layer 24 through the current spreading layer 50 .

[0061] When the substrate 10 is a silicon substrate, the current spreading layer 50 is an ITO layer, which has good conductivity and visible light transmittance, so that the light emitted by the LED light-emitting unit can be emitted through the current spreading layer 50; when the substrate 10 is a composite substrate in which a silicon layer 13 is grown on an insulating substrate 12, the current spreading layer 50 can be a metal alloy layer, and the light emitted by the LED light-emitting unit can be emitted from the insulating substrate. In this case, the insulating substrate is a transparent substrate. Fig.11 , a current spreading layer 50 can cover a groove, and the current spreading layer 50 can contact and be electrically connected with all the second semiconductor layers 24 in a groove. At this time, all the LED light-emitting units in the same groove 11 are controlled simultaneously. Figure 7 In the LED structure shown, a current spreading layer 50 ( Figure 7 The four second semiconductor layers 24 in the same groove 11 are controlled by four current spreading layers 50 , that is, the four LED light-emitting units 20 in the same groove 11 can be independently controlled.

[0062] It should be noted that Fig. 9 The substrate 10 is shown as a silicon substrate, so a second insulating layer 80 is provided on the bottom surface of the groove to facilitate the subsequent production of electrodes; Fig.11 It is shown that the substrate 10 is a composite substrate, so the second insulating layer is not provided on the bottom surface of the groove, and the insulating property of the insulating substrate 12 is utilized to facilitate the subsequent manufacture of electrodes.

[0063] The conductivity type of the second semiconductor layer 24 is P type, and the first electrode 60 is an anode. The first electrode 60 is electrically connected to the second semiconductor layer 24 through the current spreading layer 50 to provide an electrical signal to the second semiconductor layer 24 .

[0064] Optionally, the LED structure also includes: a second electrode 70, the second electrode 70 penetrates the first insulating layer 40 and contacts the substrate 10, the substrate 10 and the buffer layer 21 include N-type doped material, and the second electrode 70 is electrically connected to the first semiconductor layer 22 through the substrate 10 and the buffer layer 21.

[0065] The substrate 10 and the buffer layer 21 include N-type doped materials, which can make the substrate 10 and the buffer layer 21 conductive, and the second electrode 70 is a cathode, which can be electrically connected to the first semiconductor layer 22 through the substrate 10 and the buffer layer 21 to provide an electrical signal to the first semiconductor layer 22. At this time, the LED structure controls the electrical signal through the common cathode.

[0066] Optional, reference Figure 1 and Figure 2 The maximum width of the shape of the vertical projection of the groove 11 on the substrate 10 is 2-50 μm, and the depth of the groove 11 is greater than 0.25 times the maximum width of the groove 11.

[0067] Among them, when the maximum width of the shape of the vertical projection of the groove 11 on the substrate 10 is less than 2μm, the process is complicated; when the maximum width of the shape of the vertical projection of the groove 11 on the substrate 10 is greater than 50μm, the device structure size is too large, which is not conducive to integration; therefore, when the maximum width of the shape of the vertical projection of the groove 11 on the substrate 10 is set to 2-50μm, the process is simple and easy to operate, and is conducive to integration. The depth of the groove 11 is greater than the maximum width, so that under the condition of inputting the same current signal, the area of ​​the LED light-emitting unit grown by the epitaxial sidewall is larger and the current density is lower, thereby avoiding the LED structure from generating more heat and improving the display effect of the LED structure. Optionally, the width of the shape of the vertical projection of the groove 11 on the substrate 10 is 2μm, 5μm, 10μm, 20μm or 50μm.

[0068] The depth of the groove 11 is greater than 0.25 times the maximum width of the groove 11, so that the area of ​​the epitaxial sidewall in the same groove is greater than the maximum opening area of ​​the groove. Optionally, the maximum depth of the groove 11 can be controlled according to Si substrates with different crystal orientations. For example, in Si <100> The above production Figure 5 For the grooves shown, the groove depth is a maximum of 0.7 times the groove width.

[0069] Optional, reference Figure 7 On the multiple outer side walls of each groove 11, LED light-emitting units 20 emitting light of the same color are arranged.

[0070] Among them, reference Figure 7 , an LED light emitting unit 20 is respectively arranged on each outer side wall of each groove 11, and the multiple LED light emitting units 20 formed on multiple outer side walls of a groove 11 emit light of the same color, and the multiple LED light emitting units 20 formed by multiple grooves emit light of the same color; or, refer to Figure 8 , an LED light-emitting unit 20 is disposed on the multiple extended side walls of each groove 11, one groove forms one LED light-emitting unit 20, and multiple LED light-emitting units 20 formed by multiple grooves emit light of the same color. Exemplarily, the LED light-emitting unit 20 can be a blue LED light-emitting unit. Exemplarily, the LED light-emitting unit 20 can also be a red LED light-emitting unit or a green LED light-emitting unit.

[0071] Optional, Fig.12is a schematic diagram of another LED structure provided in the first embodiment of the present invention, referring to Fig.11 and Fig.12 The LED structure further includes: a first light conversion layer 301, the first light conversion layer 301 is located between the multiple LED light-emitting units 20 in the groove 11, and the first light conversion layer 301 is used to convert the color of the light emitted by the LED light-emitting unit 20. Optionally, the first light conversion layer 301 covers a portion of the surface of the LED light-emitting unit 20 away from the side of the epitaxial side wall.

[0072] Optional, Fig.13 is a schematic diagram of another LED structure provided in the first embodiment of the present invention, referring to Fig.13 The LED structure further includes: a second light conversion layer 302 , and the second light conversion layer 302 is located on a side of the LED light emitting unit 20 away from the substrate 10 .

[0073] Optional, reference Fig.13 , the second light conversion layer 302 is located on the side of the first light conversion layer 301 away from the substrate 10. Optionally, refer to Fig.13 Along the direction from the silicon layer 13 to the first insulating layer 40 , the thickness of the first light conversion layer 301 and the second light conversion layer 302 is not less than 10 μm, so as to improve the light conversion efficiency of the light conversion layer.

[0074] Optional, reference Fig.13 , the epitaxial side wall A1 is perpendicular to the insulating substrate 12; optionally, Fig.14 is a schematic diagram of another LED structure provided in the first embodiment of the present invention, referring to Fig.14 , the epitaxial side wall A1 is not perpendicular to the insulating substrate 12.

[0075] Optional, Fig.15 is a schematic diagram of another LED structure provided in the first embodiment of the present invention, referring to Fig.15 After the LED light-emitting unit 20 is epitaxially produced on the epitaxial side wall A1 of the groove 11, a second light conversion layer 302 is arranged on the side of the LED light-emitting unit 20 away from the insulating substrate 12, and the thickness of the second light conversion layer 302 is not less than 10μm to improve the light conversion efficiency of the light conversion layer; a light blocking layer 401 is arranged between the multiple LED light-emitting units 20 in the groove 11, so that one groove 11 includes multiple LED light-emitting units 20 with independent light emission, thereby improving the resolution.

[0076] The materials of the first light conversion layer 301 and the second light conversion layer 302 include any one of phosphors and quantum dots, so that the LED light-emitting unit is converted into light of any color through the first light conversion layer 301 and the second light conversion layer 302 to achieve full-color display.

[0077] Optional, reference Fig.11 The upper surface of the first light conversion layer 301 is lower than the upper surface of the second semiconductor layer 24 . The upper surface of the second semiconductor layer 24 is a surface away from the insulating substrate 12 . The first light conversion layer 301 does not cover the upper surface of the second semiconductor layer 24 , so that the current spreading layer 50 is electrically connected to the second semiconductor layer 24 .

[0078] Optional, reference Fig.12 , the groove 11 includes a first groove 111, a second groove 112 and a third groove 113; the first light conversion layer 301 includes a first color light conversion layer 31 and a second color light conversion layer 32, the first color light conversion layer 31 is used to convert the first color light emitted by the LED light-emitting unit 20 into a second color, and the second color light conversion layer 32 is used to convert the first color light emitted by the LED light-emitting unit 20 into a third color; the second groove 112 is filled with the first color light conversion layer 31, and the third groove 113 is filled with the second color light conversion layer 32.

[0079] The LED light-emitting unit 20 may be a blue LED light-emitting unit, the first color light conversion layer 31 may convert the blue light emitted by the blue LED light-emitting unit into green light, and the second color light conversion layer 32 may convert the blue light emitted by the blue LED light-emitting unit into red light, thereby realizing full-color display of the LED structure. Optionally, the LED light-emitting unit 20 may be a blue LED light-emitting unit, and the first groove 111 may be filled with a brightening material, a blue light phosphor, or a blue light quantum dot to improve the purity and luminous efficiency of the blue light in the first groove 111.

[0080] Optional, Fig.16 is a top view of another LED structure provided in the first embodiment of the present invention, referring to Fig.16 The multiple epitaxial side walls of each groove 11 have different areas, and the multiple epitaxial side walls of each groove 11 are provided with LED light-emitting units 20 that emit light of different colors.

[0081] Among them, the multiple epitaxial side walls of each groove 11 have different areas. The smaller the area, the faster the In doping rate / the slower the Al doping rate, and the longer the wavelength of the light emitted by the active layer in the LED light-emitting unit 20, so that three LED light-emitting units 20 with different colors of light can be grown in one groove 11. Optionally, the multiple LED light-emitting units 20 in one groove 11 are independently controlled to emit light at the same time, and the light is mixed in the groove to emit white light, and finally the LED structure as a whole emits white light; optionally, the multiple LED light-emitting units 20 in one groove 11 are independently controlled not to emit light at the same time, and finally the LED structure is used for full-color display.

[0082] Optional, reference Fig.16The LED light-emitting unit 20 includes a first color LED light-emitting unit 201, a second color LED light-emitting unit 202 and a third color LED light-emitting unit 203; the first color LED light-emitting unit 201, the second color LED light-emitting unit 202 and the third color LED light-emitting unit 203 are respectively arranged on the outer side walls with different areas of each groove 11.

[0083] The first color LED light emitting unit 201 is a blue LED light emitting unit, the second color LED light emitting unit 202 is a green LED light emitting unit, and the third color LED light emitting unit 203 is a red LED light emitting unit.

[0084] Optionally, in each groove 11, a third insulating layer 90 is disposed between two adjacent epitaxial side walls, so that the multiple epitaxial side walls of each groove 11 have different areas. Specifically, the LED light-emitting unit is grown only on the epitaxial side walls, and by growing on epitaxial side walls of different areas, an LED light-emitting unit emitting three colors of light is finally realized in one groove.

[0085] It should be noted that Fig.16 Only Si <100> Take the inverted trapezoidal groove with four epitaxial sidewalls formed by the crystal direction as an example; <110> In the groove with six epitaxial side walls formed by the crystal orientation, two groups of epitaxial side walls are formed by the third insulating layer, each group of epitaxial side walls includes three epitaxial side walls with different areas. After the LED light-emitting units are grown, one groove includes two groups of LED light-emitting units emitting three colors of light.

[0086] Embodiment 2

[0087] The embodiment of the present invention provides a method for manufacturing an LED structure based on the above embodiment. Fig.17 is a flow chart of a method for manufacturing an LED structure provided in the second embodiment of the present invention, referring to Fig.17 , the preparation method comprises:

[0088] S110, providing a substrate, and manufacturing a first insulating layer having a plurality of patterns on the substrate.

[0089] S120, using the first insulating layer as a mask, etching the substrate to form grooves, wherein each groove includes at least one epitaxial sidewall, and within the same groove, the area of ​​the epitaxial sidewall is larger than the maximum opening area of ​​the groove.

[0090] S130, epitaxially fabricating an LED light-emitting unit on at least one epitaxial side wall of the groove.

[0091] Among them, reference Figure 1 and Figure 2, a first insulating layer 40 having a plurality of openings may be formed on the substrate 10 by photolithography or wet etching.

[0092] Optionally, the side wall of the epitaxially manufactured LED light emitting unit is Si <111> Crystal direction, can be etched into <100> The silicon material is formed as Figure 5 The groove shown in the figure can be formed by etching the crystal direction <110> The silicon material is formed as Figure 6 Optionally, the sidewalls are treated with an alkaline solution to form a Si <111> Crystal direction.

[0093] Optionally, LED light-emitting units emitting light of the same color are arranged on the multiple epitaxial side walls of each groove. After the LED light-emitting units are epitaxially manufactured on at least one epitaxial side wall of the groove, it also includes: filling a light conversion layer between the multiple LED light-emitting units in the groove, the light conversion layer covering part of the LED light-emitting units, and the light conversion layer being used to convert the color of the light emitted by the LED light-emitting unit.

[0094] Among them, the light conversion layer can convert the color of the light emitted by the LED light-emitting unit to achieve full-color display.

[0095] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

Claims

1. An LED structure, characterized in that: include: A substrate (10), wherein a plurality of grooves (11) are arranged on one side of the substrate (10), and a first insulating layer (40) is arranged on the substrate (10) between the plurality of grooves (11), wherein each of the grooves (11) comprises at least one epitaxial sidewall (A1), and within the same groove (11), the area of ​​the epitaxial sidewall (A1) is greater than the maximum opening area of ​​the groove (11); A plurality of LED light-emitting units (20), each of the LED light-emitting units (20) being located on at least one of the extension side walls (A1) of the groove (11).

2. The LED structure according to claim 1, characterized in that: The substrate (10) is a composite substrate on which a silicon layer (13) is fabricated on an insulating substrate (12); the groove (11) penetrates the silicon layer (13); and the epitaxial sidewall (A1) is Si <111> Crystal direction.

3. The LED structure according to claim 1, characterized in that: The substrate (10) is a silicon substrate, the groove (11) is located on one side of the silicon substrate, and the epitaxial sidewall (A1) is Si <111> Crystal orientation; The LED structure further comprises a second insulating layer (80), wherein the second insulating layer (80) is at least located on the bottom surface of the groove (11).

4. The LED structure according to any one of claims 2 and 3, characterized in that: The surface of the substrate (10) close to the first insulating layer (40) is Si <100> When the epitaxial sidewall (A1) is oriented in the same direction as the bottom surface of the groove (11), the angle between the epitaxial sidewall (A1) and the bottom surface of the groove (11) is greater than 90°; or, The surface of the substrate (10) close to the first insulating layer (40) is Si <110> When the crystal orientation is the same, the angle between the epitaxial side wall (A1) and the bottom surface of the groove (11) is ≥90°.

5. The LED structure according to claim 1, characterized in that: The LED light-emitting unit (20) comprises a buffer layer (21), a first semiconductor layer (22), an active layer (23) and a second semiconductor layer (24) which are stacked in sequence.

6. The LED structure according to claim 5, characterized in that: Also includes: A third insulating layer (90) is located at an angle formed by two adjacent epitaxial side walls, wherein the third insulating layer (90) enables the same groove (11) to include a plurality of independent LED light-emitting units (20).

7. The LED structure according to claim 5, characterized in that: The buffer layer (21), the first semiconductor layer (22), the active layer (23) and the second semiconductor layer (24) form an annular structure surrounding the inner circle of the groove (11), so that the same groove (11) includes an independent LED light-emitting unit (20).

8. The LED structure according to claim 5, characterized in that: Also includes: The first semiconductor layer (22) covers the buffer layer (21), the active layer (23) covers the first semiconductor layer (22), and the second semiconductor layer (24) covers the active layer (23).

9. The LED structure according to claim 8, characterized in that: Also includes: A first electrode (60), wherein the first electrode (60) is electrically connected to the second semiconductor layer (24).

10. The LED structure according to claim 9, characterized in that: Also includes: a current spreading layer (50), the current spreading layer (50) being located on a side of the first insulating layer (40) away from the substrate (10), wherein the current spreading layer (50) is in contact with the second semiconductor layer (24); The first electrode (60) is electrically connected to the second semiconductor layer (24) through the current spreading layer (50).

11. The LED structure according to claim 10, characterized in that: Also includes: A second electrode (70), wherein the second electrode (70) penetrates the first insulating layer (40) and contacts the substrate (10), the substrate (10) and the buffer layer (21) comprising an N-type doped material, and the second electrode (70) is electrically connected to the first semiconductor layer (22) through the substrate (10) and the buffer layer (21).

12. The LED structure according to claim 1, characterized in that: The maximum width of the shape of the vertical projection of the groove (11) on the substrate (10) is 2-50 μm, and the depth of the groove (11) is greater than 0.25 times the maximum width of the groove (11).

13. The LED structure according to claim 1, characterized in that: LED light-emitting units (20) emitting light of the same color are arranged on the multiple outer side walls of each groove (11).

14. The LED structure according to claim 13, characterized in that: Also includes: A first light conversion layer (301), wherein the first light conversion layer (301) is located between the plurality of LED light-emitting units (20) in the groove (11).

15. The LED structure according to claim 13, characterized in that: Also includes: A second light conversion layer (302), wherein the second light conversion layer (302) is located on a side of the LED light emitting unit (20) away from the substrate (10).

16. The LED structure according to claim 1, characterized in that: Also includes: A DBR layer is located between the LED light-emitting unit (20) and the epitaxial side wall, and the material of the DBR layer is a semiconductor material.

17. The LED structure according to claim 1, characterized in that: The multiple epitaxial side walls of each of the grooves (11) have different areas, and the multiple epitaxial side walls of each of the grooves (11) are provided with LED light-emitting units (20) that emit light of different colors.

18. The LED structure according to claim 16, characterized in that: In each of the grooves (11), a third insulating layer (90) is arranged between two adjacent epitaxial side walls, so that the plurality of epitaxial side walls of each of the grooves (11) have different areas.

19. A method for manufacturing an LED structure, characterized in that: include: Providing a substrate (10), and manufacturing a first insulating layer (40) having a plurality of patterns on the substrate (10); Using the first insulating layer (40) as a mask, etching the substrate (10) to form grooves (11), wherein each groove (11) comprises at least one epitaxial sidewall (A1), and within the same groove (11), the area of ​​the epitaxial sidewall (A1) is greater than the maximum opening area of ​​the groove (11); An LED light-emitting unit (20) is epitaxially manufactured on at least one of the epitaxial side walls (A1) of the groove (11).

20. The manufacturing method according to claim 19, characterized in that: LED light-emitting units (20) emitting light of the same color are arranged on the multiple outer side walls of each of the grooves (11). After epitaxially manufacturing an LED light-emitting unit (20) on at least one of the epitaxial side walls of the groove (11), the method further comprises: A light conversion layer (30) is filled between the plurality of LED light-emitting units (20) in the groove (11), the light conversion layer (30) covering a portion of the LED light-emitting unit (20), and the light conversion layer (30) is used to perform color conversion on light emitted by the LED light-emitting unit (20).

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