Micro LED display panel and forming method thereof

Abstract

The application provides a MicroLED display panel and a forming method thereof, and the MicroLED display panel comprises a driving wafer and a MicroLED device; the driving wafer has opposite first and second surfaces, and a region close to the first surface of the driving wafer is distributed with a driving circuit; a plurality of through silicon vias are arranged between the second surface and the driving circuit, and the through silicon vias are filled with an interconnection layer; the MicroLED device is located on the side of the second surface of the driving wafer; and the MicroLED device is electrically connected with the driving circuit through the interconnection layer. The application is a kind of BSI image sensor process, so that the high-stress MicroLED device is located on the side of the second surface of the driving wafer, that is, the high-stress MicroLED device is far away from the driving circuit, so as to avoid the damage caused by the stress such as thermal expansion of the MicroLED device (for example, GaN layer) directly applied to the driving circuit, and thus the reliability is improved.

Description

Technical Field

[0001] This invention belongs to the field of integrated circuit manufacturing technology, specifically relating to a MicroLED display panel and its forming method. Background Technology

[0002] MicroLED (Micro Light Emitting Diode) display is a next-generation display technology that has emerged after LCD and OLED displays. MicroLED displays use LED chips (MicroLED chips) with dimensions ranging from a few micrometers to tens of micrometers as pixel units, arranged closely in an array. Each chip can be independently driven to emit light. MicroLED displays offer numerous advantages, including self-illumination, high efficiency, long lifespan, and ultra-high resolution. Potential applications for MicroLED displays range from near-eye displays such as AR / VR, to power-sensitive wearable devices and mobile devices, and even ultra-large screens exceeding 100 inches.

[0003] MicroLED (also known as MicroLED, mLED, or μLED) displays are fabricated using two traditional architectures. The first involves directly attaching (bonding) a μLED single-chip or die to the surface of the driver wafer closest to the driver circuit. In this method, the GaN layer within the μLED single-chip or die experiences high stress directly on the driver circuit, easily causing it to collapse and fail. The second method involves directly fabricating epitaxial layers (LED epitaxial layers) on the surface of the driver wafer closest to the driver circuit. These LED epitaxial layers consist of high-stress GaN stacks, and this high stress can easily cause the driver circuit to split and fail. Summary of the Invention

[0004] The purpose of this invention is to provide a MicroLED display panel and its forming method, which avoids damage to the driving circuit and improves reliability.

[0005] The present invention provides a MicroLED display panel, comprising: a driving wafer and a MicroLED device; the driving wafer has a first surface and a second surface opposite to each other, and a driving circuit is distributed in the region of the driving wafer adjacent to the first surface; a plurality of through-silicon vias are disposed between the second surface and the driving circuit, and the through-silicon vias are filled with an interconnect layer; the MicroLED device is located on one side of the second surface of the driving wafer; the MicroLED device is electrically connected to the driving circuit through the interconnect layer.

[0006] Furthermore, the MicroLED device includes a MicroLED wafer, a MicroLED chip block, or an array of MicroLED chip particles.

[0007] Furthermore, an isolation layer is formed between the second surface of the driving wafer and the MicroLED chip chips distributed in the MicroLED chip block or array, and the through silicon via also penetrates the isolation layer.

[0008] Furthermore, the MicroLED wafer includes a growth substrate, a Ga base layer, and an epitaxial structure layer sequentially located on the second surface of the driving wafer, and the through-silicon via also penetrates the growth substrate.

[0009] Furthermore, the growth substrate includes a SiC substrate or a sapphire substrate; the Ga base layer includes an N-type GaN layer or an N-type GaAs layer; and the epitaxial structure layer includes a quantum well layer, a P-type GaN layer, or a P-type GaAs layer.

[0010] Furthermore, the driving wafer includes a driving substrate, which is a silicon substrate with a (111) crystal plane.

[0011] Furthermore, it also includes: a carrier wafer; the carrier wafer is bonded to the first surface of the driving wafer.

[0012] Furthermore, it also includes:

[0013] An insulating layer covering the surface of the carrier wafer away from the driving wafer and the sidewall surface;

[0014] A lead-out hole, wherein the lead-out hole penetrates the insulating layer and the carrier wafer;

[0015] A lead-out metal layer is provided, which fills the lead-out hole and is electrically connected to the drive circuit.

[0016] Furthermore, it also includes:

[0017] An insulating layer covering the surface of the carrier wafer away from the driving wafer and the sidewall surface;

[0018] A redistributed metal layer covers the insulating layer located on the sidewall of the wafer, covers the insulating layer at both ends of the side of the wafer away from the driving wafer, and covers the surface of the wafer periphery on the first surface of the driving wafer. The redistributed metal layer located on the first surface is electrically connected to the driving circuit.

[0019] Furthermore, the material of the carrier wafer includes at least one of Si, Al2O3, AlN, PCB, Cu, or graphene.

[0020] The present invention also provides a method for forming a MicroLED display panel, comprising:

[0021] A driving wafer is provided, the driving wafer having opposing first and second surfaces, and driving circuits are distributed in the region of the driving wafer adjacent to the first surface;

[0022] Multiple through-silicon vias are formed, the through-silicon vias penetrating a portion of the thickness of the driving wafer from the second surface, and the through-silicon vias are located above the driving circuit;

[0023] An interconnect layer is formed, which fills the through-silicon via and is electrically connected to the driving circuit.

[0024] A MicroLED device is formed, the MicroLED device being located on one side of the second surface of the driving wafer; the MicroLED device is electrically connected to the interconnect layer.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] This invention provides a MicroLED display panel and its formation method. The MicroLED display panel includes a driving wafer and MicroLED devices. The driving wafer has a first surface and a second surface facing each other. A driving circuit is distributed in the region of the driving wafer adjacent to the first surface. A plurality of through-silicon vias (TSVs) are disposed between the second surface and the driving circuit, and the TSVs are filled with an interconnect layer. The MicroLED devices are located on one side of the second surface of the driving wafer. The MicroLED devices are electrically connected to the driving circuit through the interconnect layer. This invention is a BSI (Backside Illumination) image sensor manufacturing process, which places the high-stress MicroLED devices on one side of the second surface of the driving wafer. This keeps the high-stress MicroLED devices away from the driving circuit, avoiding direct application of thermal expansion stress (e.g., GaN layer) of the MicroLED devices to the driving circuit, thus preventing damage and improving product reliability. Attached Figure Description

[0027] Figure 1a This is a schematic diagram of the first type of lead-out hole wiring method for a MicroLED display panel according to an embodiment of the present invention.

[0028] Figure 1b This is a schematic diagram of the structure of the first MicroLED display panel redistribution metal layer lead-out method according to an embodiment of the present invention.

[0029] Figure 2 This is a schematic diagram of a second type of MicroLED display panel according to an embodiment of the present invention.

[0030] Figure 3 This is a schematic diagram of a third type of MicroLED display panel according to an embodiment of the present invention.

[0031] Figure 4 This is a schematic diagram of the MicroLED display panel forming method according to an embodiment of the present invention.

[0032] Figures 5 to 12 This is a schematic diagram of each step in the MicroLED display panel formation method according to an embodiment of the present invention.

[0033] The accompanying figure is labeled as follows:

[0034] 10-Carrier wafer; 20-Driver wafer; 201-Driver circuit; V1-Through silicon via; 30-Isolation layer; 40-Interconnect layer; 51-MicroLED chip; 52-MicroLED chip block; 53-MicroLED wafer; 53a-Growth substrate; 53b-Ga base layer; 53c-Epipolar structure layer; 60-Insulating layer; 70-Lead-out metal layer; 80-Insulating layer; 90-Redistribution metal layer. Detailed Implementation

[0035] Based on the above research, embodiments of the present invention provide a MicroLED display panel and a method for forming the same. The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description. It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0036] This invention provides a MicroLED display panel, comprising: a driving wafer and a MicroLED device; the driving wafer has a first surface and a second surface opposite to each other, and a driving circuit is distributed in the region of the driving wafer adjacent to the first surface; a plurality of through-silicon vias are disposed between the second surface and the driving circuit, and the through-silicon vias are filled with an interconnect layer; the MicroLED device is located on one side of the second surface of the driving wafer; the MicroLED device is electrically connected to the driving circuit through the interconnect layer.

[0037] Specifically, the MicroLED device includes a MicroLED wafer, a MicroLED chip block, or an array of MicroLED chip particles.

[0038] like Figure 1a , Figure 1b and Figure 2 As shown, the MicroLED display panel includes a driver wafer 20 and MicroLED devices; Figure 1a and Figure 1b The MicroLED device described herein is an array of MicroLED chip particles (single chip) 51; Figure 2 The MicroLED device described herein is a MicroLED chip block 52. The driving wafer 20 has a first surface f1 and a second surface f2 opposite to each other. A driving circuit 201 is distributed in the region of the driving wafer 20 adjacent to the first surface f1. A plurality of through-silicon vias (TSVs) are disposed between the second surface f2 and the driving circuit 201, and the TSVs are filled with an interconnect layer 40. An isolation layer 30 is formed between the second surface f2 of the driving wafer 20 and the MicroLED chips distributed in the MicroLED chip block or array, and the TSVs also penetrate the isolation layer. Figure 1a and Figure 1b Each MicroLED chip 51 is electrically connected to the driving circuit 201 through an interconnect layer 40 in a through-silicon via. Figure 2 The MicroLED chip block 52 is a collection of multiple MicroLED chips that have not been diced. The MicroLED chips in the MicroLED chip block 52 are electrically connected to the driving circuit 201 through the interconnect layer 40 in the through silicon via.

[0039] The driving wafer 20 includes a driving substrate (not shown) and driving circuitry 201 located on the driving substrate. One or more dielectric layers, such as silicon dioxide (SiO2) layers, are formed over the driving substrate. Wiring and / or contacts of the driving circuitry 201 may be formed in or over one or more dielectric layers. The driving substrate may be a semiconductor substrate, such as an amorphous semiconductor substrate, a polycrystalline semiconductor substrate, or a single-crystal semiconductor substrate. The semiconductor substrate is, for example, a silicon substrate; preferably, the driving substrate is a silicon substrate with a (111) crystal plane, which has high single-crystal structure strength and overall single-crystal lattice stability, providing better support for subsequent deposited growth substrates (e.g., SiC) and epitaxial structure layers, or isolation layers and MicroLED devices.

[0040] The driving circuit 201 is used to control millions of pixels on the MicroLED chip to present an image on the MicroLED display panel. Each driving circuit may include a single semiconductor device, such as a metal-oxide-semiconductor field-effect transistor (MOSFET), a thin-film transistor (TFT), a high electron mobility transistor (HEMT), a heterojunction bipolar transistor (HBT), a metal-semiconductor FET (MESFET), or a metal-insulator-semiconductor FET (MISFET), or an integrated circuit including two or more of the above types of devices.

[0041] Examples of MicroLED chips include GaN-based UV / blue / green MicroLEDs, AlInGaP-based red / orange MicroLEDs, and GaAs or InP-based infrared (IR) MicroLEDs. MicroLEDs offer the high density required for light field displays. Also known as mLEDs or μLEDs, MicroLEDs provide superior performance, including brightness and energy efficiency, compared to other display technologies such as liquid crystal displays (LCDs) or organic LED (OLEDs).

[0042] The driving circuit 201 can be configured to provide appropriate signals, voltages, and / or currents to drive or operate the MicroLED chip (e.g., select the light-emitting element, control settings, or control brightness). The driving circuit 201 can be configured to drive a single MicroLED chip or multiple MicroLED chips. In some embodiments, a one-to-one correspondence may exist, where one driving circuit 201 can be used to drive or operate a corresponding MicroLED chip. In other embodiments, a one-to-many correspondence may exist, where one driving circuit 201 can be used to drive or operate multiple MicroLED chips. The MicroLED chip produces one or more colors of light. The MicroLED chip may emit red, green, and blue light.

[0043] The MicroLED display panel further includes a carrier wafer 10; the carrier wafer 10 is bonded to the first surface f1 of the driving wafer 20. In a cross-section perpendicular to the upper and lower surfaces of the carrier wafer 10, the carrier wafer 10 is inverted trapezoidal or rectangular. The material of the carrier wafer 10 includes at least one of Si, Al2O3, AlN, PCB, Cu, or graphene.

[0044] Figure 1a A schematic diagram of the first type of lead-out hole wiring method for MicroLED display panels is shown. Figure 1b A schematic diagram of the first MicroLED display panel redistribution metal layer lead-out method is shown.

[0045] like Figure 1a As shown, the MicroLED display panel further includes: an insulating layer 60 covering the side surface and sidewall surface of the carrier wafer 10 away from the driving wafer 20; a lead-out hole penetrating the insulating layer 60 and the carrier wafer 10; and a lead-out metal layer 70 filling the lead-out hole and electrically connected to the driving circuit 201. In this embodiment, the electrical signals of the driving circuit 201 are led out through the lead-out hole.

[0046] like Figure 1b As shown, the MicroLED display panel further includes: an insulating layer 80, which covers the side surface of the carrier wafer 10 away from the driving wafer 20 and the sidewall surface; a redistributed metal layer 90, which covers the insulating layer 80 located on the sidewall of the carrier wafer 10, covers the insulating layers 80 at both ends of the bottom of the carrier wafer 10 (the side away from the driving wafer 20), and covers the surface of the carrier wafer 10 on the first surface f1 of the driving wafer 20. The redistributed metal layer 90 located on the first surface f1 is electrically connected to the driving circuit 201. In this embodiment, the electrical signals of the driving circuit 201 are led out by means of the redistributed metal layer.

[0047] Figure 1a , Figure 1b and Figure 2 In the illustrated embodiment, the arrayed MicroLED chip particles (single chips) 51 or MicroLED chip blocks 52 are located on one side of the second surface f2 of the driving wafer 20; there is a driving substrate and an isolation layer 30 between the driving circuit 201 and the MicroLED chip particles 51 or MicroLED chip blocks 52, and the MicroLED device is electrically connected to the driving circuit 201 through the interconnect layer 40 in the through-silicon via, so that the high-stress MicroLED chip particles 51 or MicroLED chip blocks 52 are kept away from the driving circuit 201, avoiding the direct application of stress such as thermal expansion of the MicroLED device (e.g., GaN layer) to the driving circuit and causing damage, thereby improving reliability.

[0048] like Figure 3 As shown, the MicroLED display panel includes a driver wafer 20 and MicroLED devices; Figure 3 The MicroLED device described herein is a MicroLED wafer 53. Figure 3 The driver wafer 20 and carrier wafer 10 are described above. Figure 1a , Figure 1b and Figure 2The same as in the previous embodiment will not be repeated. In this embodiment, a MicroLED wafer 53 is formed on the second surface f2 of the driving wafer 20. The MicroLED wafer 53 includes a growth substrate 53a, a Ga base layer 53b, and an epitaxial structure layer 53c sequentially located on the second surface f2 of the driving wafer 20. The through-silicon via (TSV) also penetrates the growth substrate 53a. The growth substrate 53a includes a SiC substrate or a sapphire substrate; the Ga base layer 53b includes an N-type GaN layer or an N-type GaAs layer; and the epitaxial structure layer 53c includes a quantum well layer, a P-type GaN layer, or a P-type GaAs layer. In this embodiment, through the interconnect layer 40 in the TSV, the electrodes of each MicroLED chip in the MicroLED wafer 53 are electrically connected to the driving circuit 201 on the driving wafer 20, so that the pixels of each MicroLED chip can be driven; that is, through the interconnect layer 40 in the TSV, the driving circuit 201 provides pixel driving for the MicroLED chip.

[0049] Figure 3 In the embodiment shown, the MicroLED wafer 53 is located on the second surface f2 side of the driving wafer 20; there is a driving substrate between the driving circuit 201 and the MicroLED wafer 53, and the MicroLED wafer 53 is electrically connected to the driving circuit 201 through the interconnect layer 40, so that the high-stress MicroLED wafer 53 is away from the driving circuit 201, avoiding the direct application of stress such as thermal expansion of the MicroLED wafer 53 (e.g., GaN layer) to the driving circuit and causing damage, thereby improving reliability.

[0050] It should be understood that Figure 1b The diagram shows a schematic of the first MicroLED display panel with a redistributed metal layer 90-way lead-out method. Figure 2 The second type of MicroLED display panel, wherein the MicroLED device is a MicroLED chip block 52. Figure 3 The third type of MicroLED display panel uses a MicroLED wafer 53 as the MicroLED device. Both the second and third types of MicroLED display panels can employ a redistributed metal layer wiring method, which is similar to... Figure 1b The description of the first type of MicroLED display panel is the same as that in the previous article, so it will not be repeated here.

[0051] This invention also provides a method for forming a MicroLED display panel, such as... Figure 4 As shown, it includes:

[0052] Step S1: Provide a driving wafer, the driving wafer having a first surface and a second surface opposite each other, and driving circuits are distributed in the region of the driving wafer adjacent to the first surface;

[0053] Step S2: Form a plurality of through-silicon vias (TSVs), wherein the TSVs penetrate a portion of the thickness of the driving wafer from the second surface, and the TSVs are located above the driving circuit;

[0054] Step S3: Form an interconnect layer, wherein the interconnect layer fills the through-silicon via and is electrically connected to the driving circuit;

[0055] Step S4: Form a MicroLED device, wherein the MicroLED device is located on one side of the second surface of the driving wafer; the MicroLED device is electrically connected to the interconnect layer.

[0056] The following is combined with Figures 5 to 12 This invention provides a detailed description of each step in the method for forming a MicroLED display panel according to an embodiment of the present invention.

[0057] like Figure 5 As shown, a driving wafer 20 is provided, the driving wafer 20 having a first surface f1 and an initial surface f0 opposite each other, and a driving circuit 201 is distributed in the region of the driving wafer 20 adjacent to the first surface f1.

[0058] like Figure 6 and Figure 7 As shown, the first surface f1 of the driving wafer 20 is bonded to the carrier wafer 10. One side of the initial surface f0 of the driving wafer 20 is thinned, and the thinned surface of the driving wafer 20 becomes the second surface f2.

[0059] like Figure 8 As shown, a through-silicon via (TSV) V1 is formed on the thinned driving wafer 20. The TSV V1 penetrates a portion of the thickness of the driving wafer 20 from the second surface f2 and is located above the driving circuit 201. The TSV V1 can be formed using a dry etching method.

[0060] like Figure 9 As shown, an isolation layer 30 is formed, which at least covers the second surface f2; preferably, the insulating layer may also cover the sidewall of the through-silicon via V1. Exemplarily, the isolation layer 30 is, for example, a silicon oxide layer.

[0061] like Figure 10As shown, an interconnect layer 40 is formed, which fills the through-silicon via V1 and is electrically connected to the driving circuit 201. A MicroLED chip 51 is formed above the isolation layer 30 and the interconnect layer 40. Forming the MicroLED chip 51 is a post-processing step and can be achieved using a die-mount method. The MicroLED chip 51 is electrically connected to the interconnect layer 40; the MicroLED chip is also referred to as mLED or μLED.

[0062] Next, as Figure 1a As shown, a chamfer is formed on the carrier wafer 10, so that the carrier wafer 10 is inverted trapezoidal in cross-section perpendicular to the upper and lower surfaces of the carrier wafer 10. In an alternative embodiment, the cross-sectional shape of the carrier wafer 10 may also be rectangular. The chamfer can be formed by wet etching or dry etching. An insulating layer 60 is formed on the side surface of the carrier wafer 10 away from the driving wafer 20 and on the sidewall surface; a lead-out hole is formed, the lead-out hole penetrating the insulating layer 60 and the carrier wafer 10; a lead-out metal layer 70 is formed, the lead-out metal layer 70 filling the lead-out hole and electrically connected to the driving circuit 201. The signal of the driving circuit 201 is led out through the lead-out metal layer 70 for easy external electrical connection.

[0063] Figure 2 The method for forming the MicroLED display panel shown is as follows: Figure 9 and Figure 2 As shown, an interconnect layer 40 is formed, which fills the through-silicon via V1 and is electrically connected to the driving circuit 201. A MicroLED chip block 52 is formed, which is electrically connected to the interconnect layer 40.

[0064] Figure 3 The method for forming the MicroLED display panel shown below Figure 8 ,like Figure 11 As shown, a growth substrate 53a is formed, which covers the second surface f2 of the driving wafer 20. Specifically, a filling layer can be formed in the through-silicon via V1, preferably a free-flowing organic solvent BARC (Bottom Anti-Reflective Coating). The growth substrate 53a is formed, covering the second surface f2 of the driving wafer 20 and the upper surface of the filling layer. The growth substrate 53a is etched to form an opening directly above the through-silicon via V1, which penetrates the growth substrate 53a and communicates with the through-silicon via. This can also be understood as the through-silicon via V1 extending upwards to the upper surface of the growth substrate 53a, i.e., the through-silicon via V1 penetrates the growth substrate 53a and a portion of the thickness of the driving wafer 20. Next, the filling layer in the through-silicon via V1 is removed.

[0065] like Figure 12 As shown, an interconnect layer 40 is formed, which fills the through-silicon via V1 and is electrically connected to the driving circuit 201. A Ga substrate 53b is formed on the growth substrate 53a, and then an epitaxial structure layer 53c is formed on the Ga substrate 53b. The Ga substrate 53b has pads (not shown) distributed corresponding to the interconnect layer 40, and the pads are electrically connected to the interconnect layer 40. The Ga substrate 53b is, for example, an N-type GaN layer, and the epitaxial structure layer 53c may include a quantum well layer, a P-type GaN layer, or other multilayer structures.

[0066] like Figure 12 and Figure 3 As shown, a chamfer and a metal layer 70 are formed on the carrier wafer 10. Referring to the formation method of the MicroLED display panel in Figure 1, further details are omitted. A MicroLED wafer 53 is formed on the driver wafer 20, and includes several MicroLED chips. Through the interconnect layer 40 in the through-silicon vias, the electrodes of each MicroLED chip in the MicroLED wafer 53 are electrically connected to the driver circuit 201 on the driver wafer 20, thereby enabling each MicroLED chip to be driven. Each MicroLED chip may have two contacts: one connected to the driver circuit 201 through the interconnect layer 40 in the through-silicon via, and the other connected to ground (i.e., the common electrode).

[0067] In summary, this invention provides a MicroLED display panel and its forming method. The MicroLED display panel includes a driving wafer and MicroLED devices. The driving wafer has a first surface and a second surface facing each other. A driving circuit is distributed in the region of the driving wafer adjacent to the first surface. A plurality of through-silicon vias (TSVs) are disposed between the second surface and the driving circuit, and the TSVs are filled with an interconnect layer. The MicroLED devices are located on one side of the second surface of the driving wafer. The MicroLED devices are electrically connected to the driving circuit through the interconnect layer. This invention is a BSI (Backside Illumination) image sensor manufacturing process that places the high-stress MicroLED devices on one side of the second surface of the driving wafer. This keeps the high-stress MicroLED devices away from the driving circuit, avoiding direct application of stress such as thermal expansion of the MicroLED devices (e.g., GaN layers) to the driving circuit, thus improving product reliability.

[0068] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. The methods disclosed in the embodiments are described simply because they correspond to the devices disclosed in the embodiments; relevant details can be found in the method section.

[0069] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A MicroLED display panel, characterized in that, include: Driver wafers and MicroLED devices; The driving wafer has a first surface and a second surface opposite to each other, and the driving circuit is distributed in the region of the driving wafer adjacent to the first surface; A plurality of through-silicon vias are provided between the second surface and the driving circuit, and the through-silicon vias are filled with an interconnect layer; the MicroLED device is located on one side of the second surface of the driving wafer; the MicroLED device is electrically connected to the driving circuit through the interconnect layer; The MicroLED device includes a MicroLED wafer, a MicroLED chip block, or an array of MicroLED chip particles; the MicroLED device includes a GaN layer; the MicroLED wafer includes a plurality of MicroLED chips, and the electrodes of each MicroLED chip are electrically connected to the driving circuit, so that each MicroLED chip can be driven; the MicroLED display panel further includes a carrier wafer; the carrier wafer is bonded to the first surface of the driving wafer; A through-hole is formed in the carrier wafer, and a lead-out metal layer fills the lead-out hole and is electrically connected to the driving circuit; or a redistributed metal layer covers the sidewall of the carrier wafer, and the redistributed metal layer is electrically connected to the driving circuit.

2. The MicroLED display panel as described in claim 1, characterized in that, An isolation layer is formed between the second surface of the driving wafer and the MicroLED chip particles distributed in the MicroLED chip block or array, and the through silicon via also penetrates the isolation layer.

3. The MicroLED display panel as described in claim 1, characterized in that, The MicroLED wafer includes a growth substrate, a Ga base layer, and an epitaxial structure layer sequentially located on the second surface of the driving wafer, and the through-silicon via also penetrates the growth substrate.

4. The MicroLED display panel as described in claim 3, characterized in that, The growth substrate includes a SiC substrate or a sapphire substrate; the Ga base layer includes an N-type GaN layer or an N-type GaAs layer; the epitaxial structure layer includes a quantum well layer, a P-type GaN layer or a P-type GaAs layer.

5. The MicroLED display panel as described in any one of claims 1 to 4, characterized in that, The driving wafer includes a driving substrate, which is a silicon substrate with a (111) crystal plane.

6. The MicroLED display panel as described in claim 1, characterized in that, Also includes: An insulating layer covering the surface of the carrier wafer away from the driving wafer and the sidewall surface; The lead-out hole penetrates the insulating layer and the carrier wafer.

7. The MicroLED display panel as described in claim 1, characterized in that, Also includes: An insulating layer covering the surface of the carrier wafer away from the driving wafer and the sidewall surface; The redistributed metal layer covers the insulating layer located on the sidewall of the wafer, covers the insulating layer at both ends of the side of the wafer away from the driving wafer, and covers the surface of the wafer periphery on the first surface of the driving wafer. The redistributed metal layer located on the first surface is electrically connected to the driving circuit.

8. The MicroLED display panel as described in claim 1, characterized in that, The carrier wafer is made of at least one of Si, Al2O3, AlN, PCB, Cu, or graphene.

9. A method for forming a MicroLED display panel, characterized in that, include: A driving wafer is provided, the driving wafer having opposing first and second surfaces, and driving circuits are distributed in the region of the driving wafer adjacent to the first surface; Provide a carrier wafer; bond the carrier wafer to the first surface of the driving wafer; A through-hole is formed in the carrier wafer, and the lead-out metal layer fills the lead-out hole and is electrically connected to the driving circuit. Alternatively, a redistributed metal layer may be used to cover the sidewalls of the wafer carrier, and the redistributed metal layer may be electrically connected to the driving circuit. Multiple through-silicon vias are formed, the through-silicon vias penetrating a portion of the thickness of the driving wafer from the second surface, and the through-silicon vias are located above the driving circuit; An interconnect layer is formed, which fills the through-silicon via and is electrically connected to the driving circuit. A MicroLED device is formed, wherein the MicroLED device is located on one side of the second surface of the driving wafer; the MicroLED device is electrically connected to the interconnect layer; the MicroLED device includes a MicroLED wafer, a block of MicroLED chips, or an array of MicroLED chips; the MicroLED device includes a GaN layer; the MicroLED wafer includes a plurality of MicroLED chips, and the electrodes of each MicroLED chip are electrically connected to the driving circuit, so that each MicroLED chip can be driven.

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