A preparation method of a display module, a chip structure and a display module

Abstract

The application relates to a display module preparation method, a chip structure and a display module. The display module preparation method comprises the following steps: S1: dividing a substrate into an etching area and a chip area, wherein one side of the substrate is a chip growth surface, and the other side is a back surface; forming a light shielding layer on the chip growth surface or the back surface of the etching area of the substrate respectively, and forming a chip array on the chip growth surface of the chip area of the substrate; S2: bonding the chip array and a substrate; and S3: irradiating the chip array on the back surface side of the substrate with laser, so that the chip array is separated from the substrate. The display module preparation method forms a light shielding layer on one surface of the etching area in advance before laser peeling, so that the laser cannot penetrate the etching area and irradiate semiconductor fragments generated on the surface of the etching area due to incomplete etching, thereby avoiding the problem that the semiconductor fragments on the surface of the etching area fall and affect the driving circuit on the substrate, and improving the electrical performance and yield of the display module.

Description

Technical Field

[0001] This invention relates to the field of chip technology, and in particular to a method for manufacturing a display module, a chip structure, and a display module. Background Technology

[0002] Micro-LEDs (μ-LEDs) are light-emitting arrays formed by assembling micron-sized light-emitting diode (LED) chips onto a driver circuit board. They are an active-emitting matrix display technology with characteristics such as high brightness, high saturation, fast response speed, thin and light structure, and long lifespan. They have extremely important applications in various fields such as micro-display products, AR (augmented reality) / VR (virtual reality), optical communication, solid-state lighting, and military aerospace.

[0003] Mass transfer technology is a key technology for the mass production of Micro-LED display modules. It involves using a high-precision chip transfer device to transfer chips grown on a substrate in batches onto the substrate, achieving a good electrical and mechanical connection between the chips and the driving circuitry. Currently, there are four main mass transfer technologies: pick-and-place technology, roller transfer technology, self-assembly technology, and laser lift-off (LLO) technology. Among them, LLO technology is suitable for chips of different sizes, shapes, and materials, and has good defect detection capabilities and high-speed transfer capabilities, making it a commonly used mass transfer method in industry.

[0004] Currently, the method for fabricating Micro-LED display modules using LLO technology includes the following steps: forming a semiconductor layer on the chip growth surface of a substrate; etching the semiconductor layer and forming two electrodes on the etched surface of the semiconductor layer to form a chip array; bonding the chip array to the substrate; and irradiating the chip array from the back of the substrate with a laser to separate the chip array from the substrate. In actual production processes, Micro-LED display modules fabricated using the above method often exhibit issues such as individual chips failing to emit light properly, flickering, or insufficient brightness, affecting the overall yield of the Micro-LED display module. Summary of the Invention

[0005] Based on this, the purpose of the present invention is to provide a method for manufacturing a display module that can improve electrical performance and yield.

[0006] This invention is achieved through the following technical solution:

[0007] A method for manufacturing a display module, characterized by comprising the following steps:

[0008] S1: Divide the substrate into an etching area and a chip area, wherein one side of the substrate is a chip growth surface and the other side is a back surface; a light-shielding layer is formed on the chip growth surface or the back surface of the etching area of ​​the substrate, and a chip array is formed on the chip growth surface of the chip area of ​​the substrate.

[0009] S2: Bond the chip array to the substrate;

[0010] S3: Irradiate the chip array with a laser on the back side of the substrate, thereby separating the chip array from the substrate.

[0011] Before laser stripping, this invention forms a light-shielding layer on one surface of the etched area, preventing the laser from penetrating the etched area and irradiating semiconductor fragments on its surface caused by incomplete etching. This avoids the problem of semiconductor fragments falling from the etched area surface and affecting the driving circuit on the substrate. In addition, the light-shielding layer can also prevent the laser from irradiating the driving circuit, preventing the surface metal of the driving circuit from being decomposed by the laser. It has a good protective effect on the driving circuit on the substrate surface, thereby significantly improving the electrical performance and yield of the display module.

[0012] Further, step S1 specifically involves: dividing the substrate into an etching area and a chip area, wherein one side of the substrate is the chip growth surface and the other side is the back side; firstly, a light-shielding layer is formed on the chip growth surface of the etching area; then, a chip array is formed on the chip growth surface of the chip area.

[0013] Furthermore, before forming the chip array in step S1, a passivation layer is formed on the surface of the light-shielding layer and the chip growth surface of the chip region of the substrate. This passivation layer can solve problems such as low flatness and lattice mismatch that may occur after the light-shielding layer is formed, thereby improving the growth quality of the semiconductor layer.

[0014] Further, step S1 specifically involves: dividing the substrate into an etching area and a chip area, wherein one side of the substrate is a chip growth surface and the other side is a back surface; forming a light-shielding layer on the back surface of the etching area and forming a chip array on the chip growth surface of the chip area.

[0015] Furthermore, the light-shielding layer has a laser transmittance of less than 1%.

[0016] Furthermore, the width of the light-shielding layer is greater than or equal to the width of the etched area, and the width difference between the light-shielding layer and the etched area is less than 2 μm.

[0017] Furthermore, the formation process of the light-shielding layer is as follows: a sacrificial layer is formed on the chip growth surface or back surface of the substrate, the sacrificial layer covering the chip area of ​​the substrate; the light-shielding layer is formed in the etching area of ​​the substrate adjacent to the sacrificial layer; and the sacrificial layer is removed.

[0018] Furthermore, the process of forming the light-shielding layer is as follows: etching the chip growth surface or back surface of the etched area of ​​the substrate to form a receiving groove; filling the receiving groove with a light-shielding material to form the light-shielding layer.

[0019] The present invention also provides a chip structure, including a substrate, a chip array, and a light-shielding layer; wherein the substrate is divided into a chip region and an etching region, and one side of the substrate is a chip growth surface and the other side is a back surface; the chip array is disposed on the chip growth surface of the chip region of the substrate, and the light-shielding layer covers the chip growth surface or the back surface of the etching region of the substrate.

[0020] Furthermore, the light-shielding layer covers the chip growth surface of the etched area of ​​the substrate.

[0021] Furthermore, it also includes a passivation layer that covers the surface of the light-shielding layer and the chip growth surface of the chip region of the substrate, and is located between the substrate and the chip array.

[0022] Furthermore, the light-shielding layer covers the back side of the etched area of ​​the substrate.

[0023] The present invention also provides a chip structure, wherein the display module is prepared by the preparation method according to any one of claims 1 to 4.

[0024] Compared with existing technologies, the present invention provides a method for fabricating a display module, a chip structure, and a display module. First, the substrate is divided into an etching region and a chip region. A light-shielding layer is formed on one surface of the etching region to block laser irradiation of semiconductor fragments on the surface of the etching region. This effectively prevents problems such as short circuit failure of the substrate's driving circuit caused by falling semiconductor fragments. Simultaneously, the introduction of the light-shielding layer also blocks laser irradiation of the substrate's driving circuit, avoiding the phenomenon of laser decomposition of the surface metal of the driving circuit, further improving the protection effect on the driving circuit. The resulting display module has the advantages of high yield, good electrical performance, and excellent display effect.

[0025] To better understand and implement this invention, the following detailed description is provided in conjunction with the accompanying drawings. Attached Figure Description

[0026] Figure 1 This is a schematic diagram illustrating the principle of semiconductor debris generation during the manufacturing process of a display module.

[0027] Figure 2 This is a schematic diagram illustrating the steps of a method for manufacturing a display module provided by the present invention;

[0028] Figure 3This is a schematic diagram illustrating the steps of a method for manufacturing a display module according to an embodiment of the present invention;

[0029] Figure 4 This is a schematic flowchart illustrating a method for manufacturing a display module according to an embodiment of the present invention.

[0030] Figure 5 This is a schematic diagram of the process of forming a light-shielding layer by a boss method according to an embodiment of the present invention;

[0031] Figure 6 This is a schematic diagram of a process for forming a light-shielding layer by a filling method according to an embodiment of the present invention;

[0032] Figure 7 This is a schematic diagram of a chip structure provided in an embodiment of the present invention;

[0033] Figure 8 This is a schematic diagram of a chip structure provided in an embodiment of the present invention;

[0034] Figure 9 This is a schematic diagram illustrating the steps of a method for manufacturing a display module according to an embodiment of the present invention;

[0035] Figure 10 This is a schematic flowchart illustrating a method for manufacturing a display module according to an embodiment of the present invention.

[0036] Figure 11 This is a schematic diagram of a chip structure provided in an embodiment of the present invention;

[0037] Figure 12 This is a schematic diagram of a chip structure provided in an embodiment of the present invention;

[0038] Figure 13 This is a schematic diagram of a chip structure provided in an embodiment of the present invention. Detailed Implementation

[0039] After extensive testing and a thorough investigation of factors affecting product yield, the applicant discovered that conductive fragments frequently appear on the substrate after laser lift-off. These fragments easily migrate to the driving circuitry on the substrate during fabrication and use, causing short circuits and severely impacting the electrical performance and yield of the display module. Furthermore, the inventors conducted an in-depth investigation into the reasons for the fragment residue on the substrate, finding that these fragments are made of the same material as the semiconductor layer and deducing that they originate from incompletely etched semiconductor layers in the etched areas.

[0040] Please see Figure 1This diagram illustrates the principle of semiconductor debris generation during the manufacturing process of a display module. The substrate 1 has a semiconductor layer 2 epitaxially grown on one side, which is the chip growth surface. The opposite side is the back surface of the substrate 1. The substrate 1 is divided into an etching region 11 and a chip region 12. After the semiconductor layer 2 is formed on the chip growth surface of the substrate 1, the semiconductor layer 2 on the surface of the etching region 11 needs to be etched away. The unetched semiconductor layer 2 on the surface of the chip region 12 forms independent individual chips 31. However, due to insufficient precision in the etching process, the semiconductor layer 2 on the surface of the etching region 11 is often not completely etched away. Some semiconductor debris 4 remains around the interface between the chip 31 and the substrate 1. During laser stripping of the substrate 1, the interface between these semiconductor debris 4 and the substrate strongly absorbs ultraviolet laser energy, reaching a local temperature of approximately 1000°C. The interface of the semiconductor debris 4 vaporizes and decomposes, falling onto the substrate 5. When it comes into contact with the driving circuit on the substrate, it can cause a short circuit or failure of the driving circuit, ultimately affecting the yield of the display module.

[0041] Based on this, before laser stripping, the present invention first forms a light-shielding layer 6 on the chip growth surface or back side of the substrate 1. This light-shielding layer 6 covers the etched area 11 of the substrate 1, preventing the laser from irradiating semiconductor fragments on the surface of the etched area 11 of the substrate 1. This avoids the problem of semiconductor fragments 4 falling onto the surface of the substrate 5 and affecting the electrical system of the display module, providing excellent protection for the driving circuit on the surface of the substrate 5, thereby significantly improving the electrical performance and yield of the display module. Please refer to [link to previous text]. Figure 2 This is a schematic diagram illustrating the steps of a method for manufacturing a display module provided by the present invention. The manufacturing method includes the following steps:

[0042] S1: Divide the substrate 1 into an etching region 11 and a chip region 12, wherein one side of the substrate 1 is the chip growth surface and the other side is the back side; a light-shielding layer 6 is formed on the chip growth surface or the back side of the etching region 11 of the substrate 1, and a chip array 3 is formed on the chip growth surface of the chip region 12 of the substrate 1.

[0043] S2: Bond the chip array 3 to the substrate 5;

[0044] S3: The laser is used to irradiate the chip array 3 on the back side of the substrate 1, thereby separating the chip array 3 from the substrate 1.

[0045] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments are described below.

[0046] Example 1

[0047] Please also refer to Figure 3 and Figure 4 ,in, Figure 3This is a schematic diagram illustrating the steps of a method for manufacturing a display module provided in this embodiment. Figure 4 This is a schematic flowchart illustrating a method for fabricating a display module according to this embodiment. The method for fabricating the display module includes the following steps:

[0048] S1a: The substrate 1 is divided into an etching region 11 and a chip region 12, wherein one side of the substrate is the chip growth surface and the other side is the back side; a light-shielding layer 6 is formed on the back side of the etching region 11 of the substrate 1, and a chip array 3 is formed on the chip growth surface of the chip region 12 of the substrate 1.

[0049] Specifically, step S1a includes the following sub-steps:

[0050] S11a: The substrate 1 is divided into an etching region 11 and a chip region 12, with one side of the substrate being the chip growth surface and the other side being the back side; a light-shielding layer 6 is formed on the back side of the etching region 11 of the substrate 1.

[0051] For Micro-LED display modules, substrate 1 can be a sapphire (Al2O3) substrate, a Si substrate, or a SiC substrate. The light-shielding layer 6 has a laser transmittance of less than 1% and a thickness of 1–100 μm; preferably, the thickness of the light-shielding layer 6 is 50 μm. A smaller thickness simplifies the formation process and ensures uniformity of the light-shielding layer thickness, while also ensuring complete laser blocking within this thickness range. The width of the light-shielding layer 6 should be greater than or equal to the width of the etched area 11, and the width difference should be controlled within 2 μm to avoid problems such as difficulty in peeling off the chip 31 or the laser penetrating the etched area 11 and irradiating the semiconductor fragment 4; preferably, the light-shielding layer 6 exactly covers the etched area 11. The light-shielding layer 6 is made of light-absorbing or reflective materials. Considering that the uniformity of the laser spot is reduced after the laser is reflected, and the overall effect of laser stripping is affected, the material of the light-shielding layer 6 is preferably a light-absorbing material, such as black ink made of photocurable resin mixed with carbon black particles, high-temperature resistant ferrous metal materials such as iron and chromium, laser-absorbing resin or laser-absorbing coating.

[0052] The light-shielding layer 6 can be formed using three methods: the boss method, the mask method, and the filling method.

[0053] Please see Figure 5This is a schematic diagram of the process for forming a light-shielding layer using the boss method provided in this embodiment. The formation process is as follows: a sacrificial layer 7 is formed on the back side of the chip region 12 of the substrate 1 using photolithography; that is, the sacrificial layer 7 covers the chip region 12 of the substrate 1 but does not cover the etched region 11 of the substrate 1; a light-shielding layer 6 is formed on the back side of the etched region 11 of the substrate 1 using spin coating, inkjet printing, or vapor deposition; and then the sacrificial layer 7 is removed. Specifically, when the light-shielding layer 6 uses black ink, the black ink can be filled onto the back side of the etched region 11 of the substrate 1 by spin coating or inkjet printing, and the sacrificial layer 7 is removed after the black ink has cured; when the light-shielding layer 6 uses a black metal material, the metal material can be filled onto the back side of the etched region 11 of the substrate 1 by vapor deposition, and then the sacrificial layer 7 is removed.

[0054] The mask method is a variation of the boss method. Its formation process involves: pre-forming a light-shielding mask whose shape corresponds to the etched area 11 of the substrate 1; and attaching the mask to the back side of the etched area 11 of the substrate 1 to form a light-shielding layer 6. Unlike the boss method, the mask method has the advantages of simple process, ease of implementation, and the ability to separate the light-shielding layer 6 from the substrate 1.

[0055] Since the light-shielding layer 6 formed by the boss method and the mask method both protrude from the surface of the substrate 1, it is prone to wear in practical applications, leading to a reduction in thickness. This causes its transmittance to the laser to gradually increase, failing to meet the requirement of blocking the laser from penetrating the etched area 11. Please refer to... Figure 6 This is a schematic diagram of the process for forming a light-shielding layer by filling method provided in this embodiment. The specific formation process is as follows: the back side of the etched area 11 of the substrate 1 is etched to form a receiving groove 1a; light-shielding material is filled into the receiving groove 1a by spin coating, inkjet printing or vapor deposition to form a light-shielding layer 6 covering the surface of the etched area 11. The etching process includes laser etching, dry etching or wet etching. When using laser etching, a point light source can be used to directly perform local laser etching on the back side of the etched area 11 to form receiving grooves 1a one by one; if a surface light source is used for laser etching, a template layer needs to be formed on the back side of the chip area 12 in advance, and then a large area is etched by the laser of the surface light source to form multiple receiving grooves 1a at one time, and finally the template layer is removed. When forming the receiving trench 1a by dry etching or wet etching, a template layer also needs to be formed in advance. When dry etching is used, the etching gas is BCl3 gas or a mixture of BCl3 and Cl2 gas, and the substrate 1 is placed in an ICP etching equipment for etching. When wet etching is used, the SiO2 film is used as the template layer, and the back side of the etching area 11 of the substrate 1 is etched using a sulfuric acid-phosphoric acid system.

[0056] The light-shielding layer 6, formed by the filling method, is embedded inside the substrate 1, which helps to reduce wear during the manufacturing process of the display module. In addition, an anti-wear layer can be formed on the surface of the light-shielding layer 6 by spraying, electroplating or deposition processes, which can better protect the light-shielding layer 6, extend the service life of the substrate 1 covered with the light-shielding layer 6, and reduce the production cost of the display module.

[0057] S12a: A semiconductor layer 2 is formed on the chip growth surface of substrate 1;

[0058] Specifically, a buffer layer, an n-type transport layer, a light-emitting layer, and a p-type transport layer are sequentially formed on the chip growth surface of substrate 1 through an epitaxial growth process, thereby forming semiconductor layer 2.

[0059] S13a: Etch the semiconductor layer 2 and form two electrodes 32 on the surface of the etched semiconductor layer 2, thereby forming a chip array 3 on the surface of the chip region of the substrate 1;

[0060] The schematic diagram of the chip structure prepared by steps S11a to S13b is shown below. Figure 7 and Figure 8 As shown. The chip 31 can be a GaN-based chip or a GaAs-based chip. Taking a GaN-based chip as an example, its buffer layer is undoped GaN, the n-type transport layer is n-type doped GaN, the light-emitting layer is a multiple quantum well (MQW), and the p-type transport layer is p-type doped GaN. The two electrodes 31 are a p electrode and an n electrode, respectively. The p electrode is in contact with the p-type transport layer of the chip, and the n electrode is in contact with the n-type transport layer of the chip.

[0061] S2: Bond the chip array 3 to the substrate 5;

[0062] The substrate 1 and the chip array 3 on it are placed at predetermined positions on the substrate 5. Then, the electrodes 32 on the surface of each chip 31 are bonded to the substrate 5 using pre-applied solder paste technology, metal eutectic bonding technology, or microtube technology. The substrate 5 can be a printed circuit board (PCB), a silicon substrate, a transparent glass substrate, or a flexible substrate, etc.

[0063] S3: Allow the laser to penetrate the chip region 12 and irradiate the chip array 3, so as to separate the chip array 3 from the substrate 1;

[0064] LLO (Limited Optical Loop) technology utilizes a high-energy pulsed laser beam to uniformly scan the interface between substrate 1 and chip 31 on the back side of substrate 1, causing the semiconductor material at this interface to decompose, thereby achieving the separation of substrate 1 from chip 31. The laser source for this pulsed laser can be a point source, but point sources have limitations such as slow transfer speed and low production efficiency. Therefore, a surface source composed of multiple point sources or a surface source with a large single spot is often used. The photon energy of the pulsed laser should be between the band gap of chip 31 and the band gap of substrate 1, i.e., Ei. g (chip) < E g (Laser) < E g (Substrate). Taking sapphire substrates and GaN-based chips as an example, the wavelength of the pulsed laser used during laser stripping should be 248nm or 266nm. At this time, its photon energy is greater than the band gap of GaN and less than the band gap of the sapphire substrate.

[0065] Since a light-shielding layer 6 has been formed on the back side of the etched area 11 of the substrate 1, the laser can only penetrate the chip area 12 to irradiate the chip array 3 on the back side of the substrate 1, but cannot penetrate the etched area 11 and irradiate the semiconductor fragments 4 that have not been etched cleanly. This achieves the purpose of avoiding the impact on the driving circuit and improving the electrical performance of the display module.

[0066] As a supplement to this embodiment, the formation of the light-shielding layer 6 is not necessarily limited to before the formation of the semiconductor layer 2; it can be formed at any stage before the chip array 3 is bonded to the substrate 5. However, in actual production, to avoid damage to the chip array, it is preferable to form the light-shielding layer 6 before the formation of the semiconductor layer 2.

[0067] Example 2

[0068] The difference between this embodiment and Embodiment 1 is that the light-shielding layer 6 covers the chip growth surface of the etched area 11 of the substrate 1.

[0069] Please also refer to Figure 9 and Figure 10 ,in, Figure 9 This is a schematic diagram illustrating the steps of a method for manufacturing a display module provided in this embodiment. Figure 10 This is a flowchart illustrating a method for fabricating a display module according to this embodiment. Specifically, step S1 involves:

[0070] S1b: The substrate 1 is divided into an etching region 11 and a chip region 12, wherein one side of the substrate is the chip growth surface and the other side is the back side; firstly, a light-shielding layer 6 is formed on the chip growth surface of the etching region 11 of the substrate 1, and then a chip array 3 is formed on the chip growth surface of the chip region 12 of the substrate 1.

[0071] Specifically, step S1b includes the following sub-steps:

[0072] S11b: The substrate 1 is divided into an etching region 11 and a chip region 12, with one side of the substrate being the chip growth surface and the other side being the back side; a light-shielding layer 6 is formed on the chip growth surface of the etching region 11 of the substrate 1; wherein, the method for forming the light-shielding layer 6 on the chip growth surface of the etching region 11 of the substrate 1 includes two methods: the boss method and the filling method, and the specific formation process is as described in Example 1.

[0073] S12b: A flat passivation layer 8 is formed on the surface of the light-shielding layer 6 and the chip growth surface of the chip region 12 of the substrate 1.

[0074] The flatness of the chip growth surface of substrate 1 and the lattice matching degree between substrate 1 and semiconductor layer 2 have a significant impact on the growth quality of semiconductor layer 2. After the light-shielding layer 6 is formed on the chip growth surface of the etched area 11 of substrate 1, the heights of substrate 1 and light-shielding layer 6 may be different, resulting in low surface flatness of the epitaxial growth of semiconductor layer 2. Furthermore, there is a lattice mismatch problem between light-shielding layer 6 and semiconductor layer 2. All of these factors lead to poor quality of semiconductor layer 2, and the yield of the final prepared display module is also very low. Therefore, after step 12b, a flat passivation layer 8 needs to be formed on the surface of the light-shielding layer 6 and the chip growth surface of the chip region 12 of the substrate 1, and this passivation layer 8 matches the lattice of the semiconductor layer 2. Preferably, the materials of the passivation layer 8 and the substrate 1 are consistent. For example, when the substrate 1 is a sapphire substrate, the passivation layer 8 is made of Al2O3, which is generally prepared by plasma-enhanced chemical vapor deposition (PECVD). When the substrate 1 is a Si substrate or a SiC substrate, the passivation layer 8 can be formed by depositing SiC by PECVD, which has a high lattice compatibility with the epitaxially generated semiconductor layer 2. In addition, the passivation layer 8 also helps to prevent wear of the light-shielding layer 6, extend its service life, and reduce the cost of the display module.

[0075] S13b: A semiconductor layer 2 is formed on the surface of the passivation layer 8;

[0076] S14b: The semiconductor layer 2 is etched, and two electrodes 32 are formed on the surface of the etched semiconductor layer 2, thereby forming a chip array 3 above the chip region 12 of the substrate 1; the schematic diagram of the chip structure prepared by steps S11b to S14b is shown below. Figure 11 and Figure 12 As shown.

[0077] As a supplement to Embodiment 2, a light-shielding layer 6 can also be formed after the chip array 3 is formed. In this case, step S1 specifically involves:

[0078] S1c: The substrate 1 is divided into an etching region 11 and a chip region 12, wherein one side of the substrate is the chip growth surface and the other side is the back side; firstly, a chip array 3 is formed on the chip growth surface of the chip region 12 of the substrate 1, and then a light-shielding layer 6 is formed on the chip growth surface of the etching region 11 of the substrate 1.

[0079] Since the light-shielding layer 6 is formed after the chip array 3 is formed, there are no issues such as low surface flatness of the epitaxial growth of the semiconductor layer 2 or lattice mismatch between the semiconductor layer 2 and the substrate 1 during the growth of the semiconductor layer 2. Therefore, it is not necessary to grow an additional passivation layer 8. A schematic diagram of the chip structure prepared by step S1c is shown below. Figure 13 As shown, the semiconductor fragment 4 is fixed between the etched area 11 of the substrate 1 and the light-shielding layer 6. Therefore, the laser can also penetrate the etched area 11 of the substrate 1 to irradiate the semiconductor fragment 4 and vaporize and decompose it. At this time, although the semiconductor fragment 4 is fixed on the light-shielding layer 6, the gas generated during its vaporization and decomposition process may still knock it onto the substrate, thereby causing problems such as short circuit failure of the driving circuit. Therefore, in this embodiment, it is preferable to form the light-shielding layer 6 before forming the semiconductor layer 2.

[0080] Compared with existing technologies, the present invention provides a method for fabricating a display module, a chip structure, and a display module. First, the substrate is divided into an etching region and a chip region. A light-shielding layer is formed on one surface of the etching region to block laser irradiation of semiconductor fragments on the surface of the etching region. This effectively prevents problems such as short circuit failure of the substrate's driving circuit caused by falling semiconductor fragments. Simultaneously, the introduction of the light-shielding layer also blocks laser irradiation of the substrate's driving circuit, avoiding the phenomenon of laser decomposition of the surface metal of the driving circuit, further improving the protection effect on the driving circuit. The resulting display module has the advantages of high yield, good electrical performance, and excellent display effect.

[0081] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A method for manufacturing a display module, characterized in that, Including the following steps: S1: The substrate is divided into an etching area and a chip area, wherein one side of the substrate is a chip growth surface and the other side is a back surface; a light-shielding layer is formed on the chip growth surface or the back surface of the etching area of ​​the substrate, and a chip array is formed on the chip growth surface of the chip area of ​​the substrate, wherein the process of forming the light-shielding layer is as follows: etching the chip growth surface or the back surface of the etching area of ​​the substrate to form a receiving groove; filling the receiving groove with a light-shielding material to form the light-shielding layer; S2: Bond the chip array to the substrate; S3: Irradiate the chip array with a laser on the back side of the substrate, thereby separating the chip array from the substrate.

2. The method for preparing a display module according to claim 1, characterized in that: Step S1 specifically involves: dividing the substrate into an etching area and a chip area, wherein one side of the substrate is the chip growth surface and the other side is the back side; firstly, a light-shielding layer is formed on the chip growth surface of the etching area; then, a chip array is formed on the chip growth surface of the chip area.

3. The method for preparing a display module according to claim 2, characterized in that, Before forming the chip array in step S1, the method further includes the step of forming a passivation layer on the surface of the light-shielding layer and the chip growth surface of the chip region of the substrate.

4. The method for preparing a display module according to claim 1, characterized in that: Step S1 specifically involves dividing the substrate into an etching area and a chip area, wherein one side of the substrate is the chip growth surface and the other side is the back side; a light-shielding layer is formed on the back side of the etching area, and a chip array is formed on the chip growth surface of the chip area.

5. The method for preparing a display module according to any one of claims 1 to 4, characterized in that: The light-shielding layer has a laser transmittance of less than 1%.

6. The method for manufacturing a display module according to any one of claims 5, characterized in that: The width of the light-shielding layer is greater than or equal to the width of the etched area, and the width difference between the light-shielding layer and the etched area is less than 2 μm.

7. The method for preparing a display module according to claim 6, characterized in that: The process of forming the light-shielding layer is as follows: a sacrificial layer is formed on the chip growth surface or back surface of the substrate, the sacrificial layer covering the chip area of ​​the substrate; the light-shielding layer is formed in the etching area of ​​the substrate adjacent to the sacrificial layer; and the sacrificial layer is removed.

8. A display module, characterized in that: The display module is prepared by the preparation method according to any one of claims 1 to 4.

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