Micro LED chip, growth substrate, manufacturing method of growth substrate, transfer substrate, display panel and manufacturing method of display panel

Abstract

The invention discloses a Micro LED chip, a growth substrate, a manufacturing method of the growth substrate, a transfer substrate, a display panel and a manufacturing method of the display panel, and the Micro LED chip comprises a chip main body which comprises a first side and a second side which are opposite to each other; the first side of the chip main body comprises a core epitaxial layer, a first electrode and a second electrode, and the core epitaxial layer comprises a light-emitting area; the second side of the chip main body comprises a structure epitaxial layer; the surface, away from the first side, of the structural epitaxial layer comprises a first area and a second area, the first area corresponds to the light-emitting area, and the second area is an area outside the first area; the second area comprises an overflow buffer area, and the overflow buffer area is provided with an overflow buffer structure so as to prevent the packaging glue from overflowing to affect light emitting of the light-emitting area. The overflow buffer structure can fully accommodate the excessive packaging glue due to unstable glue output during packaging, and prevents the packaging glue from overflowing to the light-emitting area of the core epitaxial layer of the chip to shield the light-emitting area, thereby effectively ensuring the light output quality of the light-emitting area.

Description

Technical Field

[0001] The present application relates to the field of Micro LED, and in particular to a Micro LED chip, a growth substrate and a manufacturing method thereof, a transfer substrate, a display panel and a manufacturing method thereof. Background Art

[0002] Inorganic micro-pixel light-emitting diodes, also known as micro-LEDs (Micro LEDs, or μ-LEDs), are widely used in self-luminous micro-displays, visible light communications, optogenetics, and other fields. Compared with traditional LEDs, Micro LEDs offer improved strain relaxation, better light extraction efficiency, more uniform current spreading, and higher output performance. Micro LEDs also offer improved thermal effects, faster response times, a wider operating temperature range, higher resolution, a wider color gamut, higher contrast, lower power consumption, and higher current density.

[0003] Existing Micro LEDs are typically packaged on an integrated circuit board (IC). A Micro LED array consisting of Micro LED units is encapsulated in the functional area on the front of the IC, forming the light-emitting area. Simultaneously, electrode structures are encapsulated in the non-functional area on the front of the IC, forming I / O ports for voltage and signal transmission. Existing Micro LED structures are susceptible to unstable control of the black matrix (BM) during the packaging process, causing BM glue to overflow into the patterned sapphire substrate (PSS), thereby affecting the light output of the Micro LED chip. Summary of the Invention

[0004] On one hand, the embodiments of the present application provide a Micro LED chip, a growth substrate and a manufacturing method thereof, and a transfer substrate to solve the problem that the existing Micro LED chip is prone to overflow of packaging glue during packaging, which affects the light emission of the Micro LED chip.

[0005] Another aspect of the present application provides a display panel and a method for manufacturing the same to improve product quality.

[0006] The embodiments of this application provide the following technical solutions:

[0007] On the one hand, an embodiment of the present application provides a Micro LED chip, comprising: a chip body, the chip body comprising a first side and a second side relative to each other; the first side of the chip body comprising a core epitaxial layer, and a first electrode and a second electrode, the core epitaxial layer comprising a light-emitting area; the second side of the chip body comprising a structural epitaxial layer; the surface of the structural epitaxial layer away from the first side comprises a first area and a second area, the first area corresponds to the light-emitting area, and the second area is an area outside the first area; the second area comprises an overflow buffer zone, the overflow buffer zone having an overflow buffer structure to prevent overflow of the encapsulation glue from affecting the light emission of the light-emitting area.

[0008] On the other hand, an embodiment of the present application also provides a growth substrate, including: a first substrate and the MicroLED chip; the upper surface of the first substrate includes a first structure, the first structure is embedded in the overflow buffer structure, and the first area surface and the second area surface outside the overflow buffer area are respectively in contact with the upper surface of the first substrate.

[0009] On the other hand, an embodiment of the present application further provides a transfer substrate, comprising:

[0010] a second substrate;

[0011] a transfer adhesive layer, the transfer adhesive layer being located on one side of the second substrate;

[0012] The first electrode and the second electrode of the plurality of Micro LED chips are located on the side of the chip body facing the second substrate, and the first electrode and the second electrode are both adhered to the transfer adhesive layer.

[0013] On the other hand, an embodiment of the present application further provides a display panel, comprising a display substrate, a display array layer, and a molded encapsulation layer;

[0014] The display substrate includes a plurality of display units, each display unit including a first bonding electrode and a second bonding electrode;

[0015] The display array layer includes a plurality of the Micro LED chips; the first electrode of the Micro LED chip is electrically connected to the first bonding electrode, and the second electrode of the Micro LED chip is electrically connected to the second bonding electrode;

[0016] The molded encapsulation layer surrounds the periphery of the Micro LED chip and covers the surface and sidewalls of the overflow buffer structure of the Micro LED chip.

[0017] On the other hand, an embodiment of the present application further provides a method for manufacturing a growth substrate, the method comprising:

[0018] providing a first substrate;

[0019] Etching the upper surface of the first substrate to form a first structure in a specific area;

[0020] Epitaxially growing a structural epitaxial layer on the upper surface of the first substrate; the lower surface of the structural epitaxial layer includes a first region and a second region, the second region includes an overflow buffer region, and the overflow buffer region has an overflow buffer structure embedded with the first structure;

[0021] Epitaxially growing a core epitaxial layer on the upper surface of the structural epitaxial layer and patterning the core epitaxial layer; the core epitaxial layer includes a light-emitting area; the first area corresponds to the light-emitting area;

[0022] A first electrode and a second electrode are fabricated in the light emitting region of the core epitaxial layer.

[0023] On the other hand, an embodiment of the present application further provides a method for manufacturing a display panel, the method comprising:

[0024] Providing the transfer substrate;

[0025] Providing a display substrate, the display substrate comprising a plurality of display units, the display units comprising a first bonding electrode and a plurality of second bonding electrodes;

[0026] Transferring the Micro LED chip on the transfer substrate to the display substrate;

[0027] bonding the first electrode and the first bonding electrode, and the second electrode and the second bonding electrode;

[0028] The Micro LED chip is packaged, and a molded packaging layer is formed around the periphery of the Micro LED chip, and the molded packaging layer covers the surface and sidewalls of the overflow buffer structure of the Micro LED chip.

[0029] Compared with the prior art, the Micro LED chip, growth substrate and manufacturing method thereof, transfer substrate, display panel and manufacturing method thereof provided in this application achieve at least the following beneficial effects:

[0030] The Micro LED chip provided in the present application includes a chip body, which includes a first side and a second side relative to each other. The first side of the chip body includes a core epitaxial layer, which includes a light-emitting area. The second side of the chip body includes a structural epitaxial layer, and the surface of the structural epitaxial layer away from the first side corresponds to an area outside the light-emitting area and is provided with an overflow buffer. An overflow buffer structure is formed in the overflow buffer. The overflow buffer structure can fully accommodate excess packaging glue due to unstable glue output during packaging, thereby preventing the packaging glue from overflowing into the light-emitting area of ​​the core epitaxial layer of the chip and causing obstruction of the light-emitting area, thereby effectively ensuring the light output quality of the light-emitting area.

[0031] Furthermore, other areas outside the overflow buffer zone of the surface of the structural epitaxial layer away from the first side have a patterned structure, which not only makes the second side of the chip body have a rough surface, which is beneficial to improving the light extraction efficiency of the chip; but also in the subsequent display panel production process, when transferring chips in large quantities, a variety of transfer methods can be used to pick up the chips, such as stamp transfer method or laser transfer method, etc. Moreover, when using the stamp transfer method, the fixed picking effect between the transfer head and the chip can be improved, which can better ensure that the chip is picked up and transferred normally, thereby improving the transfer yield and transfer efficiency when using the Micro LED chip to produce display panels. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0033] Figure 1 Schematic diagram of the structure of a Micro LED chip provided in an embodiment of the present application;

[0034] Figure 2 2 is another structural schematic diagram of the Micro LED chip provided in an embodiment of the present application;

[0035] Figure 3 2 is another structural schematic diagram of the Micro LED chip provided in an embodiment of the present application;

[0036] Figure 4 This is a schematic structural diagram of a growth substrate provided in an embodiment of the present application;

[0037] Figure 5 yes Figure 3 A schematic structural diagram of a first substrate in the growth substrate shown;

[0038] Figure 6 is another structural schematic diagram of the first substrate in an embodiment of the present application;

[0039] Figure 7 is another structural schematic diagram of a growth substrate provided in an embodiment of the present application;

[0040] Figure 8 This is a flow chart of a method for manufacturing a growth substrate provided in an embodiment of the present application;

[0041] Figure 9 This is a schematic structural diagram of a transfer substrate provided in an embodiment of the present application;

[0042] Figure 10 This is a schematic structural diagram of a display panel provided in an embodiment of the present application;

[0043] Figure 11 This is a flow chart of a method for manufacturing a display panel provided in an embodiment of the present application. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0045] In response to the problem that existing Micro LED chips are prone to BM glue overflow during packaging, affecting the light emission of the Micro LED chips, the embodiments of the present application provide a Micro LED chip, a growth substrate, a manufacturing method thereof, and a transfer substrate. A core epitaxial layer is arranged on the first side of the chip body, and a structural epitaxial layer is arranged on the opposite second side. In addition, an overflow buffer zone is provided in the area outside the light-emitting area corresponding to the surface of the structural epitaxial layer away from the first side. An overflow buffer structure is formed in the overflow buffer zone, so that it can fully accommodate the excess BM glue due to unstable glue output during packaging, thereby preventing the BM glue from overflowing into the light-emitting area of ​​the core epitaxial layer of the chip and causing obstruction of the light-emitting area.

[0046] like Figure 1 , which is a schematic structural diagram of a Micro LED chip provided in an embodiment of the present application.

[0047] The Micro LED chip 100 includes a chip body 10 , which includes a first side F1 and a second side F2 opposite to each other.

[0048] The first side F1 of the chip body 10 includes a core epitaxial layer 11 and a first electrode 12 and a second electrode 13 . The core epitaxial layer 11 includes a light-emitting region S0 .

[0049] Among them, the second side F2 of the chip body 10 includes a structural epitaxial layer 21; the surface of the structural epitaxial layer 21 away from the first side F1 includes a first area S1 and a second area S2, the first area S1 corresponds to the light-emitting area S0 of the first side F1, and the second area S2 is the area outside the first area S1; the second area S2 includes an overflow buffer zone, and the overflow buffer zone has an overflow buffer structure 210 to prevent the overflow of the packaging glue from affecting the light emission of the light-emitting area.

[0050] It should be noted that the overflow buffer area may be a partial area of ​​the second area S2, such as an edge area of ​​the second area S2 adjacent to or away from the first area S1; or the entire area of ​​the second area S2, which is not limited in this embodiment of the present application.

[0051] In some embodiments, the first region S1 and the second region outside the overflow buffer zone have a patterned structure 211 , and the shape of the overflow buffer structure 210 may be the same as or different from the shape of the patterned structure 211 .

[0052] like Figure 2 In a non-limiting embodiment shown, the core epitaxial layer 11 includes, from top to bottom, a buffer layer 111, an N-GaN layer 112, an MQW (multi-quantum well) layer 113, a P-GaN layer 114, and an ITO (conductive thin film) layer 115. A passivation layer (not shown) may also be included.

[0053] It should be noted that Figure 2 The structure of the core epitaxial layer 11 is merely an example. For different applications, the structure of the core epitaxial layer 11 may have other variations. The Micro LED chip provided in the embodiment of the present application is not limited to the specific structure of the core epitaxial layer 11, nor is it limited to the material and manufacturing process of each layer.

[0054] The structural epitaxial layer 21 can be a PSS (Patterned Sapphire Substrate), which can be designed and manufactured on the sapphire substrate by etching (dry etching or wet etching) to form a micron- or nanometer-scale pattern with specific microstructure rules, thereby controlling the output light form of the Micro LED. The concave and convex pattern on the sapphire substrate will produce light scattering or refraction effects to increase the light extraction rate.

[0055] For example, in some embodiments, the shape of the patterned structure 211 can be a groove, or a strip, a dome, a column, etc., which is not limited in the embodiments of the present application, as long as it can improve the light extraction efficiency of the Micro LED chip.

[0056] In some embodiments, the overflow buffer structure 210 may be in the form of a groove or the like. The groove may be in any of the following shapes: honeycomb, conical, trapezoidal, and the like.

[0057] Continue to refer to Figure 1 As shown, the depth d1 of the overflow buffer structure 210 is greater than the depth d2 of the patterned structure 211. The depth d1 of the overflow buffer structure 210 refers to the distance between the top surface of the overflow buffer structure 210 and the top surface of the second region S2 of the epitaxial layer 21. Similarly, the depth d2 of the patterned structure 211 refers to the distance between the top surface of the patterned structure 211 and the top surface of the first region S1 of the epitaxial layer 21.

[0058] For example, in some embodiments, the depth of the overflow buffer structure 210 may be at least 2 times greater than the depth of the patterned structure 211 .

[0059] For another example, in some embodiments, the depth of the overflow buffer structure 210 can be designed to be greater than or equal to 2 microns.

[0060] It should be noted that, depending on the application scenario of the Micro LED chip 100 and the design of the pattern shape of the overflow buffer structure 210, the depth of the overflow buffer structure 210 can be adjusted as needed, as long as it can accommodate the overflow packaging glue during packaging. In addition, the bottom surface S21 of the overflow buffer structure 210 facing the second side F2 and the bottom surface S11 of the patterned structure 211 facing the second side F2 can be located on different planes, such as Figure 1 as shown in , or in different planes, such as Figure 3 As shown in , this embodiment of the present application is not limited to this.

[0061] The Micro LED chip 100 provided in the embodiment of the present application is designed with the above-mentioned overflow buffer structure 210 on the structural epitaxial layer 21, which can fully accommodate the excess packaging glue due to unstable glue output during packaging, and prevent the packaging glue from overflowing into the light-emitting area of ​​the core epitaxial layer of the chip and blocking the light-emitting area, thereby effectively ensuring the light output quality of the light-emitting area.

[0062] Accordingly, the present invention also provides a growth substrate, such as Figure 4 The figure shows a structural diagram of the growth substrate.

[0063] The growth substrate 200 includes a first substrate 20 and the aforementioned Micro LED chip 100. The top surface S02 of the first substrate 20 includes a first structure 201 that interlocks with the overflow buffer structure 210 of the Micro LED chip 100. The surface of the first region S1 and the surface of the second region S2 outside the overflow buffer region are in contact with the top surface S02 of the first substrate 20. In other words, the top surface S02 of the first substrate 20 has a pattern that interlocks with the patterned surface of the structural epitaxial layer 21 of the Micro LED chip 100.

[0064] In order to more clearly illustrate the structure of the upper surface of the first substrate 20, Figure 5 Shown separately Figure 4 The structure of the first substrate 20 in the growth substrate 200 is shown.

[0065] Also refer to Figure 4 and Figure 5 The upper surface S02 of the first substrate 20 can also be divided into Figure 3 The first region S1 and the second region S2 of the structural epitaxial layer 21 in the Micro LED chip correspond to the first corresponding region S1 ′ and the second corresponding region S2 ′ respectively.

[0066] The second corresponding region S2' and the first corresponding region S1' may have the same or different patterns, for example, grooves, strips, domes, columns, etc., which are not limited in this embodiment of the present application. Furthermore, the depth d1' of the second corresponding region S2' is greater than the depth d2' of the first corresponding region S1'.

[0067] In actual manufacturing, the pattern on the upper surface S02 of the first substrate 20 can be formed by two etching processes.

[0068] For example, in some embodiments, in the first etching process, a pattern of a certain depth is first etched on the entire upper surface S02 of the first substrate 20, and a pattern that matches the overflow buffer structure 210 is formed in the second corresponding area S2'; then, the second corresponding area S2' is covered with a mask, and the first corresponding area S1' is etched for the second time, and a pattern that matches the patterned structure 211 is formed in the first corresponding area S1'. The depth d1' of the second corresponding area S2' is greater than the depth d2' of the first corresponding area S1'. Figure 5 shown.

[0069] For another example, in some embodiments, in the first etching process, the first mask is first used to shield the second corresponding area S2' on the upper surface S02 of the first substrate 20, and a first pattern of a certain depth is etched in the first corresponding area S1'. Then, the second mask is used to shield the first corresponding area S1', and a second pattern of a certain depth is etched in the second corresponding area S2'. The depth d1' of the second corresponding area S2' is greater than the depth d2' of the first corresponding area S1'. Figure 6 As shown in .

[0070] After forming the corresponding patterned structure on the upper surface S02 of the first substrate 20 , the epitaxial layer 11 , the core epitaxial layer 21 , the first electrode 12 and the second electrode 13 may be grown layer by layer on the upper surface S02 to form the above-mentioned structure.

[0071] The first substrate 20 and the structural epitaxial layer 11 of the Micro LED chip 100 may be made of sapphire.

[0072] When manufacturing the above-mentioned growth substrate 200, a plurality of Micro LED chips 100 can be manufactured on the first substrate 20 to form a chip array, such as Figure 7 shown.

[0073] In some embodiments, to facilitate mass transfer, a colloid layer may be further included between the upper surface S02 of the first substrate 20 and the patterned surface of the structural epitaxial layer 11 of the Micro LED chip 100 .

[0074] Accordingly, the present invention also provides a method for manufacturing a growth substrate, such as Figure 8 FIG. 1 is a flow chart of the method.

[0075] In step 801 , a first substrate is provided.

[0076] In step 802 , the upper surface of the first substrate is etched to form a first structure in a specific area.

[0077] For example, in some embodiments, the upper surface of the first substrate can be etched for the first time to form a patterned structure; then, a mask is used to cover areas outside the specific area of ​​the first substrate, and the upper surface of the first substrate is etched for the second time to form a first structure in the specific area.

[0078] Of course, there may be other etching methods, which are not limited in the embodiments of the present application.

[0079] In step 803, a structural epitaxial layer is epitaxially grown on the upper surface of the first substrate; the lower surface of the structural epitaxial layer includes a first region and a second region, the second region includes an overflow buffer region, and the overflow buffer region has an overflow buffer structure embedded with the first structure.

[0080] The depth of the overflow buffer structure is greater than the depth of the patterned structure, thereby effectively preventing the packaging glue from overflowing and affecting the light emission of the light-emitting area.

[0081] In some embodiments, the depth of the overflow buffer structure may be at least twice greater than the depth of the patterned structure.

[0082] In some embodiments, the depth of the overflow buffer structure may be greater than or equal to 2 microns, for example.

[0083] In step 804 , a core epitaxial layer is epitaxially grown on the upper surface of the structural epitaxial layer and the core epitaxial layer is patterned.

[0084] The core epitaxial layer includes a light-emitting region; the first region corresponds to the light-emitting region.

[0085] In step 805 , a first electrode and a second electrode are formed in the light emitting region of the core epitaxial layer.

[0086] Accordingly, the present application also provides a transfer substrate, such as Figure 9 Shown is a structural schematic diagram of the transfer substrate.

[0087] The transfer substrate 300 includes a second substrate 30, a transfer adhesive layer 31 located on one side of the second substrate 30, and a plurality of the aforementioned Micro LED chips 100. The first and second electrodes 12, 13 of the Micro LED chips 100 are located on the side of the chip body 10 facing the second substrate 30, and are bonded to the transfer adhesive layer 31.

[0088] During the production process, after the above-mentioned growth substrate 200 is completed, the side of the growth substrate 200 where the electrode of the Micro LED chip 100 is located is bonded to the transfer adhesive layer 31 of the second substrate 30 coated with the transfer adhesive layer 31, and then the first substrate 20 on the growth substrate 200 is removed to obtain the above-mentioned transfer substrate 300, providing the corresponding Micro LED chip 100 for the production of the display panel.

[0089] Accordingly, the embodiment of the present application further provides a display panel, such as Figure 10 The figure shows a structural diagram of the display panel.

[0090] The display panel 400 includes: a display substrate 40, a display array layer, and a molded encapsulation layer 50;

[0091] The display substrate includes a plurality of display units, each of which includes a first bonding electrode 41 and a second bonding electrode 42;

[0092] The display array layer includes a plurality of the aforementioned Micro LED chips 100 ; the first electrode 12 of the Micro LED chip 100 is electrically connected to the first bonding electrode 41 , and the second electrode 13 of the Micro LED chip 100 is electrically connected to the second bonding electrode 42 .

[0093] The molded encapsulation layer 50 surrounds the periphery of the Micro LED chip 100 and covers the surface and sidewalls of the overflow buffer structure 210 of the Micro LED chip 100 .

[0094] In some embodiments, the display panel 400 further includes a reflective layer 61 positioned between the Micro LED chip 100 and the molded encapsulation layer 50 and surrounding the first region S1 on the surface of the epitaxial layer 21 of the Micro LED chip 100. The reflective layer 61 reflects light, thereby increasing the number of photons received by the Micro LED chip 100, reducing light loss, and improving the image quality displayed by the display panel 400.

[0095] In some embodiments, the display panel 400 further includes a light-transmitting plate 62, which is applied to and completely covers the first region S1 of the epitaxial layer 21 of the structure 100. The light-transmitting plate 62 can better protect the surface of the Micro LED chip 100. The light-transmitting plate 62 can completely cover the reflective layer 61 or be in contact with the reflective layer 61, which is not limited in this embodiment.

[0096] Accordingly, the present invention also provides a method for manufacturing a display panel, such as Figure 11 FIG. 1 is a flow chart of the method, comprising the following steps:

[0097] In step 1101 , a transfer substrate is provided.

[0098] The structure of the transfer substrate can refer to the previous Figure 7 The description in the illustrated embodiment will not be repeated here.

[0099] In step 1102 , a display substrate is provided. The display substrate includes a plurality of display units. The display units include a first bonding electrode and a plurality of second bonding electrodes.

[0100] In step 1103 , the Micro LED chip on the transfer substrate is transferred to the display substrate.

[0101] For example, the Micro LED chip on the transfer substrate can be transferred to the display substrate by methods including but not limited to laser transfer and stamp transfer.

[0102] In step 1104 , the first electrode and the first bonding electrode are bonded, and the second electrode and the second bonding electrode are bonded.

[0103] For example, the display substrate may be heated to electrically connect the first electrode to the first bonding electrode and the second electrode to the second bonding electrode.

[0104] In step 1105 , the Micro LED chip is packaged, and a molded packaging layer is formed around the periphery of the Micro LED chip, and the molded packaging layer covers the surface and sidewalls of the overflow buffer structure of the Micro LED chip.

[0105] For example, Micro LED chips can be packaged using inkjet printing technology.

[0106] In some embodiments, before packaging the Micro LED chip, a reflective layer may be disposed around the first region S1 on the surface of the structural epitaxial layer 21 of the Micro LED chip 100, and a light-transmitting plate may be disposed on the surface of the first region S1. The light-transmitting plate may completely cover the reflective layer or be in contact with the reflective layer, and then the Micro LED chip may be packaged.

[0107] It should be understood that in the description of the embodiments of this application, the term "and / or" is merely a description of the association relationship between associated objects, indicating that three relationships can exist. For example, "A and / or B" can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document indicates that the associated objects are in an "or" relationship.

[0108] In addition, the orientation or position relationship indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present application.

[0109] In addition, the terms "first" and "second" are used for descriptive purposes only, and are only used to illustrate and distinguish the objects being described. There is no order, and they cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated, and cannot constitute any limitation on the embodiments of this application. Therefore, the features defined as "first" and "second" can explicitly or implicitly include at least one of such features. In the description of the embodiments of this application, the meaning of "multiple" is at least two, for example, two, three, etc., unless otherwise clearly and specifically defined.

[0110] In the embodiments of this application, unless otherwise specified or limited, terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections, electrical connections, or communication between them; direct connections, indirect connections through an intermediate medium, and internal connections between two components or interactions between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0111] In the embodiments of the present application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0112] In the embodiments of the present application, if the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" appear, it means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0113] Although the embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application. Any person skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments without departing from the spirit and scope of the present application.

Claims

1. A Micro LED chip, characterized in that: include: A chip body, the chip body including a first side and a second side relative to each other; the first side of the chip body includes a core epitaxial layer, and a first electrode and a second electrode, the core epitaxial layer including a light-emitting area; the second side of the chip body includes a structural epitaxial layer; the surface of the structural epitaxial layer away from the first side includes a first area and a second area, the first area corresponds to the light-emitting area, and the second area is an area outside the first area; the second area includes an overflow buffer area, and the overflow buffer area has an overflow buffer structure to prevent overflow of the packaging glue from affecting the light emission of the light-emitting area.

2. The Micro LED chip according to claim 1, wherein: The overflow buffer zone is an edge area of ​​the second area adjacent to or away from the first area; or the overflow buffer zone is the entire area of ​​the second area.

3. The Micro LED chip according to claim 1, wherein: The first region and a second region outside the overflow buffer zone have a patterned structure, and a shape of the overflow buffer structure is the same as or different from a shape of the patterned structure.

4. The Micro LED chip according to claim 3, wherein: The depth of the overflow buffer structure is greater than the depth of the patterned structure.

5. The Micro LED chip according to claim 4, wherein: The depth of the overflow buffer structure is at least 2 times greater than the depth of the patterned structure.

6. The Micro LED chip according to claim 4, wherein: The depth of the overflow buffer structure is greater than or equal to 2 microns.

7. The Micro LED chip according to any one of claims 1 to 4, wherein: The overflow buffer structure is in the shape of a groove.

8. The Micro LED chip according to claim 7, wherein: The groove is in any one of the following shapes: honeycomb, cone, or trapezoid.

9. A growth substrate, characterized in that include: A first substrate and the MicroLED chip according to any one of claims 1 to 8; the upper surface of the first substrate includes a first structure, the first structure is embedded in the overflow buffer structure, and the first area surface and the second area surface outside the overflow buffer area are respectively in contact with the upper surface of the first substrate.

10. A transfer substrate, characterized in that: include: a second substrate; a transfer adhesive layer, the transfer adhesive layer being located on one side of the second substrate; The Micro LED chip according to any one of claims 1 to 8, wherein the first electrode and the second electrode of the Micro LED chip are located on a side of the chip body facing the second substrate, and the first electrode and the second electrode are both adhered to the transfer adhesive layer.

11. A display panel, characterized in that: It includes a display substrate, a display array layer, and a molded packaging layer; The display substrate includes a plurality of display units, each display unit including a first bonding electrode and a second bonding electrode; The display array layer comprises a plurality of Micro LED chips according to any one of claims 1 to 8; the first electrode of the Micro LED chip is electrically connected to the first bonding electrode, and the second electrode of the Micro LED chip is electrically connected to the second bonding electrode; The molded encapsulation layer surrounds the periphery of the Micro LED chip and covers the surface and sidewalls of the overflow buffer structure of the Micro LED chip.

12. A method for manufacturing a growth substrate, characterized in that: The method comprises: providing a first substrate; Etching the upper surface of the first substrate to form a first structure in a specific area; Epitaxially growing a structural epitaxial layer on the upper surface of the first substrate; the lower surface of the structural epitaxial layer includes a first region and a second region, the second region includes an overflow buffer region, and the overflow buffer region has an overflow buffer structure embedded with the first structure; Epitaxially growing a core epitaxial layer on the upper surface of the structural epitaxial layer and patterning the core epitaxial layer; the core epitaxial layer includes a light-emitting area; the first area corresponds to the light-emitting area; A first electrode and a second electrode are fabricated in the light emitting region of the core epitaxial layer.

13. The method for manufacturing a growth substrate according to claim 12, wherein: The etching the upper surface of the first substrate to form a first structure in a specific area includes: performing a first etching on the upper surface of the first substrate to form a patterned structure; A mask is used to shield the area outside the specific area of ​​the first substrate, and a second etching is continued on the upper surface of the first substrate to form a first structure in the specific area.

14. The method for manufacturing a growth substrate according to claim 13, wherein: The depth of the overflow buffer structure is greater than the depth of the patterned structure.

15. The method for manufacturing a growth substrate according to claim 14, wherein: The depth of the overflow buffer structure is at least 2 times greater than the depth of the patterned structure.

16. The method for manufacturing a growth substrate according to claim 13, wherein: The depth of the overflow buffer structure is greater than or equal to 2 microns.

17. A method for manufacturing a display panel, characterized in that: The method comprises: Providing the transfer substrate according to claim 10; Providing a display substrate, the display substrate comprising a plurality of display units, the display units comprising a first bonding electrode and a plurality of second bonding electrodes; Transferring the Micro LED chip on the transfer substrate to the display substrate; bonding the first electrode and the first bonding electrode, and the second electrode and the second bonding electrode; The Micro LED chip is packaged, and a molded packaging layer is formed around the periphery of the Micro LED chip, and the molded packaging layer covers the surface and sidewalls of the overflow buffer structure of the Micro LED chip.

18. The method for manufacturing a display panel according to claim 17, wherein: Transferring the Micro LED chip on the transfer substrate to the display substrate includes: The Micro LED chip on the transfer substrate is transferred to the display substrate by a stamp transfer method or a laser transfer method.

19. The method for manufacturing a display panel according to claim 17, wherein: The bonding of the first electrode and the first bonding electrode, and the bonding of the second electrode and the second bonding electrode comprises: The display substrate is heated to electrically connect the first electrode to the first bonding electrode and to electrically connect the second electrode to the second bonding electrode.

20. The method for manufacturing a display panel according to any one of claims 17 to 19, wherein: The packaging of the Micro LED chip includes: The Micro LED chip is packaged by an inkjet printing process.

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