Light emitting diode panel

Abstract

The embodiment of the invention discloses a light-emitting diode panel, which is characterized in that a second conductive layer is arranged in an area corresponding to a groove to cover a first conductive layer so as to increase the thickness of the area, corresponding to the groove, of the first conductive layer, and the risk that the first conductive layer is thinned and fractured or virtually connected at the groove is made up; therefore, the connection conduction capability and the conduction stability of the first conductive layer between the light-emitting diodes are improved, and the performance and the manufacturing yield of the light-emitting diode panel are improved.

Description

Technical Field

[0001] The present application relates to the field of display technologies, and particularly to a light-emitting diode panel. Background Art

[0002] With the popularity of augmented reality (AR) and virtual reality (VR) technologies, micro-display technologies with high brightness and high pixel per inch (PPI) have become the best display solutions. Micro-display technologies based on silicon-based micro light-emitting diodes (Micro-LEDs) have become the most competitive display solutions. Different from traditional LED manufacturing processes, the manufacturing process of silicon-based micro light-emitting diodes is more complex. It is necessary to combine a driving substrate and an LED epitaxy, and then pattern the LED epitaxy and connect it to the driving substrate. When combining the LED epitaxy and the driving electrode plate, bonding metal needs to be introduced. Both the LED epitaxy and the bonding metal are relatively thick. After patterning by etching, a large trench step difference will be formed between Micro-LED pixels. When the subsequent conductive thin film is deposited again, it will become thinner or even break at the trench steps between Micro-LED pixels, affecting the performance of silicon-based micro light-emitting diodes. Summary of the Invention

[0003] Embodiments of the present application provide a light-emitting diode panel, which can improve the stability of light-emitting diode devices.

[0004] Embodiments of the present application provide a light-emitting diode panel, which includes:

[0005] A driving substrate, where the driving substrate includes a substrate and a first conductive bonding layer disposed on the substrate;

[0006] A second conductive bonding layer, which is bonded and disposed on a surface of the first conductive bonding layer away from the substrate;

[0007] A light-emitting diode epitaxial layer, where the light-emitting diode epitaxial layer includes a plurality of light-emitting diodes. The light-emitting diodes are disposed on a side of the second conductive bonding layer away from the substrate. One end of the light-emitting diode is electrically connected to the second conductive bonding layer. A trench is provided between two adjacent light-emitting diodes, and the trench penetrates through the light-emitting diode epitaxial layer, the second conductive bonding layer, and the first conductive bonding layer;

[0008] A protective layer, which covers the light-emitting diode epitaxial layer and the trench. An opening is provided on the protective layer, and the opening exposes the light-emitting diode;

[0009] A first conductive layer, which covers the protective layer and is connected to the other end of the light-emitting diode through the opening. A part of the first conductive layer covers the area of the trench;

[0010] A second conductive layer, which is directly disposed on a side of the first conductive layer away from the substrate, and the second conductive layer covers at least the area of the trench.

[0011] Optionally, in some embodiments of the present application, the first conductive layer includes a connected first portion and a second portion. The first portion is disposed in the area of the light-emitting diode, and the second portion is disposed in the area of the trench. The thickness of the first portion is greater than the thickness of the second portion.

[0012] The sum of the thickness of the second portion and the thickness of the second conductive layer is greater than or equal to the thickness of the first portion.

[0013] Optionally, in some embodiments of the present application, the trench includes a connected first groove and a second groove. The first groove penetrates through the light-emitting diode epitaxial layer, and the second groove penetrates through the second conductive bonding layer and the first conductive bonding layer.

[0014] The notch width of the first groove is greater than the notch width of the second groove. The thickness of the portion of the first conductive layer located in the first groove is greater than the thickness of the portion of the first conductive layer located in the second groove. The thickness of the portion of the second conductive layer located in the first groove is greater than the thickness of the portion of the second conductive layer located in the second groove.

[0015] The sum of the thickness of the portion of the first conductive layer located in the second groove and the thickness of the portion of the second conductive layer located in the second groove is greater than or equal to the thickness of the first portion.

[0016] Optionally, in some embodiments of the present application, the second conductive layer includes a connected covering portion and a filling portion. The covering portion covers the area of the second portion corresponding to the first groove, and the filling portion fills the recessed portion of the second portion corresponding to the second groove.

[0017] Optionally, in some embodiments of the present application, the second conductive layer covers the surface of the second portion away from the substrate.

[0018] Optionally, in some embodiments of the present application, the light-emitting diode panel further includes a third conductive layer, which is disposed between the light-emitting diode and the second conductive bonding layer, and the second groove penetrates through the third conductive layer.

[0019] Optionally, in some embodiments of the present application, the notch width of the trench is less than 0.6 micrometers.

[0020] Optionally, in some embodiments of the present application, the material of the second conductive layer is selected from at least one of metal or metal oxide.

[0021] Optionally, in some embodiments of the present application, the second conductive layer is a single film layer structure.

[0022] Optionally, in some embodiments of the present application, the second conductive layer is a multi-film layer stacked structure.

[0023] Optionally, in some embodiments of the present application, the second conductive layer includes an electroplating seed layer and an electroplating metal layer disposed on the electroplating seed layer, and the electroplating seed layer covers the first conductive layer.

[0024] In the light-emitting diode panel according to the embodiment of the present application, in the region corresponding to the trench, a second conductive layer is provided to cover the first conductive layer so as to thicken the thickness of the first conductive layer corresponding to the trench region, compensating for the risk of thinning, breaking or virtual connection of the first conductive layer at the trench, thereby improving the connection and conduction ability and the conductive stability of the first conductive layer between the light-emitting diodes, and improving the performance and manufacturing yield of the light-emitting diode panel. Description of the Drawings

[0025] Figure 1 is a schematic structural diagram of a light-emitting diode panel provided by an embodiment of the present application;

[0026] Figure 2 is Figure 1 an enlarged view of part A in

[0027] Figure 3 is Figure 1 an enlarged view of another structure of part A in

[0028] Figure 4 is a schematic structural diagram of step S1 of the method for manufacturing a light-emitting diode panel provided by an embodiment of the present application;

[0029] Figure 5 is a schematic structural diagram of step S2 of the method for manufacturing a light-emitting diode panel provided by an embodiment of the present application;

[0030] Figure 6 is a schematic structural diagram of step S3 of the method for manufacturing a light-emitting diode panel provided by an embodiment of the present application

[0031] Figure 7 is a schematic structural diagram of step S4 of the method for manufacturing a light-emitting diode panel provided by an embodiment of the present application;

[0032] Figure 8 is another schematic structural diagram of a light-emitting diode panel provided by an embodiment of the present application;

[0033] Figure 9 is Figure 8 an enlarged view of part A in Detailed implementation manners

[0034] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application. In addition, it should be understood that the specific implementation manners described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In the present application, unless otherwise stated, the orientation words such as "upper" and "lower" generally refer to the upper and lower in the actual use or working state of the device, specifically the drawing direction in the accompanying drawings; and "inner" and "outer" refer to the outline of the device; the terms "first", "second", "third", etc. are only used as labels, and no digital requirements are imposed or an order is established.

[0035] An embodiment of the present application provides a light-emitting diode panel, which will be described in detail below. It should be noted that the description order of the following embodiments does not limit the preferred order of the embodiments.

[0036] Please refer to Figure 1 and Figure 2 , an embodiment of the present application provides a light-emitting diode panel 100, which includes a driving substrate qd, a second conductive bonding layer 11, a light-emitting diode epitaxial layer 12, a protective layer 13, a first conductive layer 14, and a second conductive layer 15.

[0037] The driving substrate qd includes a substrate 16 and a first conductive bonding layer 17 disposed on the substrate 16. The second conductive bonding layer 11 is bonded and disposed on the side of the first conductive bonding layer 17 away from the substrate 16.

[0038] The light-emitting diode epitaxial layer 12 includes a plurality of light-emitting diodes LED. The light-emitting diodes LED are disposed on the side of the second conductive bonding layer 11 away from the substrate 16. One end of the light-emitting diode LED is electrically connected to the second conductive bonding layer 11. A trench g1 is disposed between two adjacent light-emitting diodes LED, and the trench g1 penetrates through the light-emitting diode epitaxial layer 12, the second conductive bonding layer 11, and the first conductive bonding layer 17.

[0039] The protective layer 13 covers the light-emitting diode epitaxial layer 12 and the trench g1. An opening 13a is disposed on the protective layer 13, and the opening 13a exposes the light-emitting diode LED.

[0040] The first conductive layer 14 covers the protective layer 13 and is connected to the other end of the light-emitting diode LED through the opening 13a. A part of the first conductive layer 14 covers the area of the trench g1. The second conductive layer 15 is directly disposed on the side of the first conductive layer 14 away from the substrate 16. The second conductive layer 15 covers at least the area of the trench g1.

[0041] In the light-emitting diode panel 100 according to the embodiment of the present application, in the area corresponding to the trench g1, the second conductive layer 15 is provided to cover the first conductive layer 14 to increase the thickness of the first conductive layer 14 in the area corresponding to the trench g1, compensate for the risk of thinning, breaking or virtual connection of the first conductive layer 14 at the trench g1, and further improve the connection and conduction ability of the first conductive layer 14 between the light-emitting diodes LED, and improve the performance and manufacturing yield of the light-emitting diode panel 100.

[0042] Optionally, the notch width of the trench g1 is less than 0.6 microns, for example, it can be 0.59 microns, 0.55 microns, 0.5 microns, 0.4 microns, 0.3 microns, 0.2 microns or 0.1 microns.

[0043] Since the second conductive layer 15 is added, the conductivity continuity and stability between the light-emitting diodes LED are improved, so the notch width of the trench g1 can be reduced to improve the resolution of the light-emitting diode panel 100.

[0044] It should be noted that the notch width of the trench g1 is the notch width k1 of the first groove g11 in the following text.

[0045] Optionally, the driving substrate qd further includes a thin-film transistor structure layer 18, and the thin-film transistor structure layer 18 is disposed between the substrate 16 and the first conductive bonding layer 17. The first conductive bonding layer 17 is electrically connected to the thin-film transistor in the thin-film transistor structure layer 18.

[0046] Optionally, the first conductive layer 14 includes a connected first part 141 and a second part 142. The first part 141 is disposed in the area of the light-emitting diode LED. The second part 142 is disposed in the area of the trench g1. The thickness of the first part 141 is greater than the thickness of the second part 142.

[0047] In the area of the trench g1, the sum of the thickness of the second part 142 and the thickness of the second conductive layer 15 is greater than or equal to the thickness of the first part 141.

[0048] In this embodiment, by setting the total thickness of the conductive stack (the second part 142 + the second conductive layer 15) in the area of the trench g1 to be greater than or equal to the thickness of the first part 141, the risk of breakage or virtual connection of the conductive layer at the trench is reduced, and the impedance of the entire first conductive layer 14 is reduced.

[0049] It should be understood that the thickness of the second part 142 is the average thickness of the second part 142, the thickness of the second conductive layer 15 is the average thickness of the second conductive layer 15, and the thickness of the first part 141 is the average thickness of the first part 141.

[0050] In some embodiments, the thickness of the second part 142 is the minimum thickness of the second part 142, the thickness of the second conductive layer 15 is the minimum thickness of the second conductive layer 15, and the thickness of the first part 141 is the maximum thickness or the average thickness of the first part 141, so as to further improve the connection conductivity stability of the conductive stack in the trench g1 region and achieve the effect of reducing impedance.

[0051] Among them, a plurality of light-emitting diodes LED are all connected to the first conductive layer 14. The resistivity of the second conductive layer 15 is less than that of the first conductive layer 14, so as to improve the conductive performance of the connection between the light-emitting diodes LED and reduce the impedance of the first conductive layer 14.

[0052] Optionally, the material of the first conductive layer 14 is a transparent conductive material, such as indium tin oxide, indium zinc oxide and other oxides.

[0053] The material of the second conductive layer 15 can be selected from at least one of metals or metal oxides. For example, metal elements selected from chromium, copper, aluminum, gold, platinum, silver, zinc, molybdenum, tantalum, titanium, tungsten, manganese, nickel, iron, cobalt, alloys composed of any of the above metal elements, or combinations of metal oxides such as indium tin oxide and indium zinc oxide with any of the above metal elements can be used.

[0054] Optionally, the second conductive layer 15 is a single-film layer structure or a multi-film layer stacked structure.

[0055] Optionally, the light-emitting diode LED includes a light-emitting layer and a first electrode and a second electrode located on opposite sides of the light-emitting layer, where the first electrode is one end of the light-emitting diode LED and the second electrode is the other end of the light-emitting diode LED.

[0056] Optionally, the trench g1 includes a first groove g11 and a second groove g12 that are connected and communicate with each other. The first groove g11 penetrates through the light-emitting diode epitaxial layer 12. The second groove g12 penetrates through the second conductive bonding layer 11 and the first conductive bonding layer 17.

[0057] The notch width k1 of the first groove g11 is greater than the notch width k2 of the second groove g12. The thickness of the part of the first conductive layer 14 located in the first groove g11 is greater than the thickness of the part of the first conductive layer 14 located in the second groove g12. The thickness of the part of the second conductive layer 15 located in the first groove g11 is greater than the thickness of the part of the second conductive layer 15 located in the second groove g12.

[0058] The sum of the thickness of the portion of the first conductive layer 14 located in the second groove g12 and the thickness of the portion of the second conductive layer 15 located in the second groove g12 is greater than or equal to the thickness of the first portion 141.

[0059] It should be understood that the second groove g12 is located in the deepest area of the groove g1. Therefore, compared with the area of the first groove g11, the second portion 142 of the first conductive layer 14 and the portion of the second conductive layer 15 located in the second groove g12 are both thinner. Thus, the second portion 142 located in the area of the second groove g12 is more likely to break or have a poor connection.

[0060] Therefore, setting the thickness of the conductive stack located in the area of the second groove g12 to be greater than or equal to the thickness of the first portion 141 of the first conductive layer 14 can more accurately compensate for the area with a thinner thickness of the second portion 142, improving the electrical connection and stability.

[0061] In addition, it can be understood that since both the first conductive layer 14 and the second conductive layer 15 are formed by a deposition process, and the first groove g11 is located in the upper area of the groove g1, the thickness of the conductive stack located in the area of the first groove g11 is thicker than that in the area of the second groove g12.

[0062] Therefore, the thickness of the conductive stack located in the area of the first groove g11 is greater than the thickness of the first portion 141 of the first conductive layer 14, further improving the electrical connection and stability, as well as reducing the impedance effect.

[0063] Optionally, the light-emitting diode panel 100 may further include a third conductive layer 19. The third conductive layer 19 is disposed between the light-emitting diode LED and the second conductive bonding layer 11, and the second groove g12 penetrates through the third conductive layer 19.

[0064] Optionally, the inclination angle a1 of the groove wall of the first groove g11 is less than the inclination angle a2 of the groove wall of the second groove g12, and the notch width k2 of the second groove g12 is less than the notch width k1 of the first groove g11, such that the volume of the second groove g12 is relatively small, making it easier for the second conductive layer 15 to fill the area of the second groove g12, thereby further improving the continuity and stability of the electrical connection of the conductive stack located in the area of the channel g1.

[0065] Optionally, the second conductive layer 15 includes a connected covering portion 151 and a filling portion 152. The covering portion 151 covers the area of the second portion 142 corresponding to the first groove g11. The filling portion 152 fills the recess ax of the second portion 142 corresponding to the second groove g12.

[0066] Among them, the filling part 152 fills the recessed part ax corresponding to the second groove g12, which not only maximally ensures the electrical conductivity stability and continuity of the conductive stack in the area of the second groove g12, but also enables the current to bypass the bottom area of the recessed part ax, reducing the current transmission path and thus improving the electrical conductivity performance.

[0067] Optionally, in some embodiments, as Figure 3 shown, the second conductive layer 15 covers the surface of the second part 142 away from the substrate 16.

[0068] The method for manufacturing the light-emitting diode panel 100 according to the embodiments of the present application includes the following steps:

[0069] Step S1, please refer to Figure 4 , pattern the light-emitting diode epitaxial material layer, the first conductive bonding material layer, the second conductive bonding material layer, and the third conductive material layer of the driving substrate qd to form the second conductive bonding layer 11, the light-emitting diode epitaxial layer 12, the first conductive bonding layer 17, and the trench g1. Subsequently, a protective material layer bh is formed on the driving substrate qd, and the protective material layer bh covers the second conductive bonding layer 11, the light-emitting diode epitaxial layer 12, the first conductive bonding layer 17, and the trench g1.

[0070] Optionally, the substrate 16 of the driving substrate qd can be a silicon-based substrate or a glass substrate, etc. The materials of the first conductive bonding layer 17 and the second conductive bonding layer 11 can each be at least one of Cr, Ti, Pt, Sn, Au, and Cu or a combination of any of the above metal elements.

[0071] Step S2, please refer to Figure 5 , pattern the protective material layer bh to form the protective layer 13 and the opening 13a, and the opening 13a exposes the light-emitting diode LED; subsequently, a first conductive layer 14 is formed on the protective layer 13. The first conductive layer 14 is connected to a plurality of light-emitting diodes LED and extends to cover the trench g1 area.

[0072] Step S3, please refer to Figure 6 , form a patterned photoresist layer pr on the first conductive layer 14, and the photoresist layer pr is correspondingly arranged in the area of the light-emitting diode LED; subsequently, a conductive material layer dd is formed on the photoresist layer pr, and the conductive material layer dd is disconnected at the edge of the photoresist layer pr to form the second conductive layer 15 covering the trench g1 area.

[0073] Step S4, please refer to Figure 7 , remove the photoresist layer pr and the conductive material layer dd located on the photoresist layer pr.

[0074] Optionally, in some embodiments, as Figure 8 and Figure 9 shown, compared withFigure 1 For a corresponding embodiment, the difference of this embodiment lies in that: the second conductive layer 15 includes an electroplating seed layer 15a and an electroplated metal layer 15b disposed on the electroplating seed layer 15a, and the electroplating seed layer 15a covers the first conductive layer 14.

[0075] The electroplated metal layer 15b fills the recess ax of the electroplating seed layer 15a located in the second groove g12 region.

[0076] Among them, compared with the chemical vapor deposition process, the electroplating process is used to form the second conductive layer 15, and the thickness of the second conductive layer 15 is more uniform, which can improve the thickness uniformity of the conductive stack in the trench g1 region, and further improve the continuity and stability of the conductive performance of the conductive stack.

[0077] It should be noted that the other structures of the light-emitting diode panel 100 in this embodiment are similar or the same as those of the corresponding Figure 1 embodiment.

[0078] In the light-emitting diode panel of the embodiment of the present application, in the region corresponding to the trench, a second conductive layer is provided to cover the first conductive layer to thicken the thickness of the first conductive layer corresponding to the trench region, to make up for the risk of thinning, breaking or virtual connection of the first conductive layer at the trench, and further improve the connection and conduction ability of the first conductive layer between the light-emitting diodes, and improve the performance and manufacturing yield of the light-emitting diode panel.

[0079] The above has introduced in detail a light-emitting diode panel provided by an embodiment of the present application. Specific examples are used in this article to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those skilled in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A light-emitting diode panel, characterized in that, comprising: a driving substrate, the driving substrate comprising a substrate and a first conductive bonding layer provided on the substrate; a second conductive bonding layer, the second conductive bonding layer being bonded and provided on a surface of the first conductive bonding layer away from the substrate; a light-emitting diode epitaxial layer, the light-emitting diode epitaxial layer comprising a plurality of light-emitting diodes, the light-emitting diodes being provided on a side of the second conductive bonding layer away from the substrate, one end of the light-emitting diode being electrically connected to the second conductive bonding layer, a trench being provided between adjacent two of the light-emitting diodes, the trench penetrating through the light-emitting diode epitaxial layer, the second conductive bonding layer and the first conductive bonding layer; a protective layer, the protective layer covering the light-emitting diode epitaxial layer and the trench, an opening being provided on the protective layer, the opening exposing the light-emitting diode; a first conductive layer, the first conductive layer covering the protective layer and being connected to the other end of the light-emitting diode through the opening, a part of the first conductive layer covering the area of the trench; a second conductive layer, the second conductive layer being directly provided on a surface of the first conductive layer away from the substrate, the second conductive layer at least covering the area of the trench.

2. The light-emitting diode panel according to claim 1, characterized in that, the first conductive layer comprises a connected first part and a second part, the first part being provided in the area of the light-emitting diode, the second part being provided in the area of the trench, the thickness of the first part being greater than the thickness of the second part; in the trench area, the sum of the thickness of the second part and the thickness of the second conductive layer is greater than or equal to the thickness of the first part.

3. The light-emitting diode panel according to claim 2, characterized in that, the trench comprises a connected first groove and a second groove, the first groove penetrating through the light-emitting diode epitaxial layer, the second groove penetrating through the second conductive bonding layer and the first conductive bonding layer; the notch width of the first groove is greater than the notch width of the second groove, the thickness of the part of the first conductive layer located in the first groove is greater than the thickness of the part of the first conductive layer located in the second groove, the thickness of the part of the second conductive layer located in the first groove is greater than the thickness of the part of the second conductive layer located in the second groove; the sum of the thickness of the part of the first conductive layer located in the second groove and the thickness of the part of the second conductive layer located in the second groove is greater than or equal to the thickness of the first part.

4. The light-emitting diode panel according to claim 3, characterized in that, the second conductive layer comprises a connected covering part and a filling part, the covering part covering the area of the second part corresponding to the first groove, the filling part filling in a recessed part of the second part corresponding to the second groove.

5. The light-emitting diode panel according to claim 3, characterized in that, the second conductive layer covers a surface of the second part away from the substrate.

6. The light-emitting diode panel according to claim 3, characterized in that, The light-emitting diode panel further includes a third conductive layer disposed between the light-emitting diode and the second conductive bonding layer, and the second groove penetrates through the third conductive layer.

7. The light-emitting diode panel according to claim 1, wherein, the notch width of the groove is less than 0.6 micrometers.

8. The light-emitting diode panel according to any one of claims 1-7, wherein, the second conductive layer is a single film layer structure.

9. The light-emitting diode panel according to any one of claims 1-7, wherein, the second conductive layer is a multi-film layer stacked structure.

10. The light-emitting diode panel according to claim 9, wherein, the second conductive layer includes an electroplating seed layer and an electroplating metal layer disposed on the electroplating seed layer, and the electroplating seed layer covers the first conductive layer.

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