LED packaging structure, through hole metallization method, packaging method and packaging system

Abstract

The invention relates to the technical field of display device packaging, in particular to an LED packaging structure, a through hole metallization method, a packaging method and a packaging system. The packaging method comprises the following steps: carrying out copper glue printing on the front surface of the glass substrate to form a copper glue coating, and synchronously carrying out vacuum suction on the back surface of the glass substrate, so that a through hole is filled with copper glue to form a conductive path; and preparing a first conductive layer and a second conductive layer on the front surface and the back surface of the glass substrate, and after devices of the first conductive layer and the second conductive layer are installed, attaching the glass cover plate to the glass substrate to complete packaging. According to the application, copper glue printing on the front surface of the glass substrate is matched with synchronous vacuum suction on the back surface, so that dense metal filling, reliable interconnection and no cavity in the through hole metallization process of the glass substrate are realized. Therefore, the core problems of tedious glass substrate through hole metallization process, non-uniform filling and poor interconnection reliability are directly solved, and a high-reliability conductive path basis is provided for subsequent packaging.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display device packaging, in particular to an LED packaging structure, a through-hole metallization method, a packaging method and a packaging system. BACKGROUND

[0002] With the continuous evolution of display technology, Micro-LED display devices have become the core development direction of the new generation of high-end display field due to their advantages of high brightness, high contrast, long service life and low power consumption. In the packaging process of Micro-LED, the COB (Chip On Board) packaging technology gradually becomes the mainstream application scheme due to its high integration, simplified structure and improved device reliability. However, the existing COB process generally uses a printed circuit board (PCB) or an organic substrate as a bearing platform, which has a high coefficient of thermal expansion (CTE). In large-size, high-resolution display applications, the mismatch of thermal stress can easily cause problems such as substrate warping, solder cracking and uneven display, which seriously restricts the flatness and long-term reliability of the panel.

[0003] In related technologies, glass substrates are considered as ideal carrier materials to solve the above problems due to their low thermal expansion coefficient and excellent optical transparency, surface flatness and other characteristics. However, the through-hole metallization process of glass substrates has a significant bottleneck: conventional methods such as sputtering, electroplating or seed layer deposition have complicated process steps, high cost, and are prone to defects such as uneven metal filling, high hole porosity and poor interconnection reliability during hole filling. Specifically, the sputtering process cannot achieve uniform coverage of deep holes, electroplating requires complex seed layer deposition and is prone to stress concentration in the hole, and seed layer deposition leads to prolonged process cycle and reduced yield. These problems not only hinder the large-scale application of glass substrates in COB packaging, but also directly affect the optical performance (such as light interference) and environmental durability (such as moisture resistance and oxidation resistance) of Micro-LED display devices, and a new efficient and reliable through-hole metallization process is urgently needed to break through the technical bottleneck. SUMMARY

[0004] In related technologies, the through-hole metallization process of display devices is prone to defects such as uneven metal filling, high hole porosity and poor interconnection reliability.

[0005] In a first aspect, an embodiment of the present application provides a through-hole metallization method for an LED packaging structure, which includes: Performing copper glue printing on the front surface of the glass substrate and simultaneously performing vacuum suction on the back surface of the glass substrate to fill the through holes on the glass substrate with copper glue.

[0006] In a second aspect, the present application provides a packaging method for an LED packaging structure, which includes: Copper paste is printed on the front side of a glass substrate with through holes to form a copper paste coating, and a vacuum is simultaneously performed on the back side of the glass substrate so that the copper paste fills the through holes to form a conductive path. A first conductive layer and a second conductive layer are respectively formed on the front and back sides of the glass substrate, so that the first conductive layer and the second conductive layer are electrically connected through the copper paste in the through hole; After the devices with the first and second conductive layers are installed, the glass cover is attached to the glass substrate to complete the encapsulation.

[0007] In conjunction with the second aspect, in one embodiment, before attaching the glass cover to the glass substrate to complete the encapsulation, the method further includes: pressing a black adhesive layer onto the front side of the glass substrate so that the gaps between all LED devices on the first conductive layer are filled with black adhesive film.

[0008] In conjunction with the second aspect, in one embodiment, the step of laminating the black adhesive layer onto the front side of the glass substrate includes: The black adhesive layer is arranged between the LED device and the planar mold on the first conductive layer, and the thickness of the black adhesive layer is greater than the height of the LED device in the thickness direction of the glass substrate. The black adhesive layer is pressed onto the glass substrate.

[0009] In conjunction with the second aspect, in one embodiment, the step of attaching the glass cover to the glass substrate to complete the encapsulation includes: attaching the glass cover to the adhesive layer on the surface of the black adhesive layer, and combining the glass cover, the black adhesive layer and the glass substrate.

[0010] In conjunction with the second aspect, in one embodiment, the step of performing copper paste printing on the front side of the glass substrate and simultaneously performing vacuum suction on the back side of the glass substrate includes: A continuous copper paste coating is printed on the front side of the glass substrate, the copper paste coating covering the opening area of ​​the through hole; The back side of the glass substrate is placed in a vacuum environment, and the back side of the glass substrate is simultaneously evacuated during the printing process.

[0011] In conjunction with the second aspect, in one embodiment, the fabrication of a first conductive layer and a second conductive layer on the front and back sides of the glass substrate, respectively, includes: Copper foil is applied to the front and back sides of the glass substrate while the copper paste is not fully cured, and the copper foil is bonded to the copper paste to form the first conductive layer and the second conductive layer.

[0012] In conjunction with the second aspect, in one embodiment, the device mounting on the first conductive layer and the second conductive layer includes: A circuit is constructed on the first conductive layer and the second conductive layer; An LED chip and a driver chip are mounted on the first conductive layer; Components are mounted on the second conductive layer.

[0013] Thirdly, this application provides a packaging system for an LED packaging structure, comprising: A hole-opening module, used to create through holes in a glass substrate; A through-hole metallization module is used to print copper paste on the front side of the glass substrate and simultaneously perform vacuum suction on the back side of the glass substrate so that the copper paste fills the through-hole to form a conductive path. A conductive layer fabrication module is used to fabricate a first conductive layer and a second conductive layer on the front and back sides of the glass substrate, respectively, so that the first conductive layer and the second conductive layer are electrically connected through the copper paste in the through hole. A device mounting module for mounting devices on the first conductive layer and the second conductive layer; The bonding and encapsulation module is used to bond the glass cover to the glass substrate to complete the encapsulation.

[0014] Fourthly, this application provides an LED packaging structure, which is prepared by the packaging method described in any of the above claims.

[0015] The beneficial effects of the technical solutions provided in this application include: This application achieves dense metal filling, reliable interconnection, and void-free via metallization during the glass substrate's through-hole process by simultaneously printing copper paste on the front side of the substrate and performing vacuum suction on the back side. This directly solves the core problems of cumbersome through-hole metallization processes, uneven filling, and poor interconnection reliability. It replaces traditional electroplating or seed layer deposition methods, significantly reducing process complexity, improving metallization yield, and providing a high-reliability conductive path foundation for subsequent packaging. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a flowchart illustrating a first specific embodiment of the encapsulation method of this application; Figure 2 This is a schematic diagram of the via opening step in a second specific embodiment of the encapsulation method of this application; Figure 3 This is a schematic diagram of the front copper paste printing step in the second specific embodiment of the packaging method of this application; Figure 4 This is a schematic diagram of the front copper sheet bonding step in a second specific embodiment of the encapsulation method of this application; Figure 5 This is a schematic diagram of the conductive layer preparation steps in a second specific embodiment of the encapsulation method of this application; Figure 6 This is a schematic diagram of the back copper paste printing step in the second specific embodiment of the packaging method of this application; Figure 7 This is a schematic diagram of the circuit construction steps in a second specific embodiment of the encapsulation method of this application; Figure 8 This is a schematic diagram of the LED device mounting steps in a second specific embodiment of the packaging method of this application; Figure 9 This is a front view of the LED device mounting steps in a second specific embodiment of the packaging method of this application; Figure 10 This is a schematic diagram of the back-side component mounting steps in a second specific embodiment of the packaging method of this application; Figure 11 This is a schematic diagram of the hot-pressing step of the black adhesive layer in the second specific embodiment of the encapsulation method of this application. Figure 12 This is a schematic diagram of the encapsulation structure after the black adhesive layer is hot-pressed in the second specific embodiment of the encapsulation method of this application; Figure 13 For this application Figure 12 A partial schematic diagram; Figure 14 This is a partial schematic diagram of the black adhesive layer in the second specific embodiment of the encapsulation method of this application; Figure 15 This is a schematic diagram of the cover plate hot pressing step in the second specific embodiment of the encapsulation method of this application; Figure 16 For this application Figure 15 A partial schematic diagram; Figure 17 This is a schematic diagram of the LED packaging structure in an embodiment of this application.

[0018] In the diagram: 1. Glass substrate; 11. Through hole; 12. Front side; 13. Back side; 14. Copper adhesive coating; 15. Copper adhesive; 16. Copper circuit; 2. Black adhesive layer; 21. Adhesive layer; 22. Plastic layer; 3. Copper foil; 31. First conductive layer; 32. Second conductive layer; 4. Glass cover plate; 5. Planar mold; 6. LED chip; 7. Driver chip; 8. Components; 9. Airbag. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0020] In related technologies, the through-hole metallization process of display devices is prone to defects such as uneven metal filling, high void ratio in the hole, and poor interconnect reliability.

[0021] In a first aspect, this application provides a method for metallizing through-holes in a glass substrate for an LED packaging structure, comprising: Step 1: Apply copper paste printing to the front side 12 of the glass substrate 1 with through holes 11.

[0022] Specifically, such as Figure 3 As shown, a layer of specially made highly conductive copper paste 15 is printed on the front side 12 of the glass substrate 1 using screen printing technology, so that the copper paste 15 covers the opening area of ​​the through hole 11 and forms a continuous copper paste coating 14 on the surface of the glass substrate 1.

[0023] It is worth noting that copper paste 15 needs to have good fluidity and shrinkage to facilitate subsequent hole filling steps.

[0024] In some alternative embodiments, the thickness of the copper paste coating 14 should be controlled between 20-40 μm.

[0025] Understandably, a copper plating thickness of 14mm within this threshold provides sufficient filler while avoiding excessive buildup. Copper vias provide excellent vertical electrical and thermal conductivity channels, aiding in chip heat dissipation.

[0026] Step 2: While printing is in progress, the back side 13 of the glass substrate 1 is placed in a vacuum environment, and the back side 13 of the glass substrate 1 is simultaneously evacuated during the printing process to extract the air inside the through hole 11 in real time.

[0027] It is worth noting that under negative pressure, the printed copper paste 15 is rapidly drawn into the through-hole 11, achieving simultaneous printing and filling. By combining copper paste printing on the front side of the glass substrate with synchronous vacuum suction on the back side, dense metal filling, reliable interconnection, and void-free via metallization are achieved within the vias during the glass substrate. This directly solves the core problems of cumbersome via metallization processes, uneven filling, and poor interconnection reliability, replacing traditional electroplating or seed layer deposition methods, significantly reducing process complexity, improving metallization yield, and providing a high-reliability conductive path foundation for subsequent packaging.

[0028] Furthermore, multiple printings are required to ensure that the through-holes are filled and to ensure that the thickness of the screen-printed copper coating 14 is uniform.

[0029] In some preferred real-time methods, the vacuum level of the vacuum environment during the suction process is controlled between -0.08 and -0.1 MPa, and the printing speed needs to match the copper paste penetration rate to prevent clogging or air bubble residue.

[0030] Understandably, for through holes 11 with high aspect ratios, multiple printing processes combined with simultaneous vacuum suction can be used to ensure complete density.

[0031] Secondly, this application provides a packaging method for an LED packaging structure. For example... Figure 1 As shown, in the first specific embodiment of this application, the packaging method of the LED packaging structure includes: Step S1: Copper paste is printed on the front side 12 of the glass substrate 1 with through holes to form a copper paste coating 14, and at the same time, vacuum suction is performed on the back side 13 of the glass substrate 1 so that the copper paste 15 fills the through holes 11 to form a conductive path.

[0032] It is worth noting that under negative pressure, the printed copper paste 15 is rapidly drawn into the through-hole 11, achieving simultaneous printing and filling. By combining copper paste printing on the front side of the glass substrate with synchronous vacuum suction on the back side, dense metal filling, reliable interconnection, and void-free via metallization are achieved within the vias during the glass substrate. This directly solves the core problems of cumbersome via metallization processes, uneven filling, and poor interconnection reliability, replacing traditional electroplating or seed layer deposition methods, significantly reducing process complexity, improving metallization yield, and providing a high-reliability conductive path foundation for subsequent packaging.

[0033] Step S2: A first conductive layer 31 and a second conductive layer 32 are respectively prepared on the front side 12 and the back side 13 of the glass substrate 1, so that the first conductive layer 31 and the second conductive layer 32 are electrically connected through the copper paste 15 in the through hole 11.

[0034] It is understood that the first conductive layer 31 and the second conductive layer 32 are electrically connected through the conductive path formed by the copper paste 15 in the through hole 11.

[0035] Optionally, the above-mentioned step S2 preparation process includes: attaching copper foil 3 to the incompletely cured copper adhesive 15, and then using hot pressing technology to tightly bond the copper foil 3 to the copper adhesive 15 to form a first conductive layer 31 and a second conductive layer 32.

[0036] It should be noted that this application is not limited to using methods other than hot pressing to prepare the first conductive layer 31 and the second conductive layer 32. In actual operation, the preparation process can be selected according to actual needs.

[0037] Step S3: After the devices of the first conductive layer 31 and the second conductive layer 32 are installed, the glass cover plate 4 is attached to the glass substrate 1 to complete the encapsulation.

[0038] It is worth noting that in the first specific embodiment of the packaging method of this application, the packaging method uses the process of "copper paste printing combined with synchronous vacuum suction" to achieve dense metal filling, reliable interconnection, and no voids in the through-hole metallization process of the glass substrate.

[0039] In the second specific embodiment provided in this application, the packaging method of the LED packaging structure includes: Step S1, as follows Figure 2 As shown, a through hole 11 is formed on the glass substrate 1.

[0040] It is understandable that a special glass plate with a low coefficient of thermal expansion and high flatness is selected as the substrate.

[0041] Step S1 above includes: Step S1a: Thoroughly clean and dry the glass substrate 1 to remove surface contaminants.

[0042] Understandably, thoroughly cleaning and drying the glass substrate surface effectively removes contaminants such as grease, dust, and oxides, ensuring that the substrate surface meets high cleanliness requirements and providing a reliable foundation for subsequent copper paste printing, vacuum filling, and copper foil bonding processes.

[0043] Step S1b: Open a hole in glass substrate 1.

[0044] In the first specific embodiment of step S1b of this application, the through hole can be etched by laser or dry etching.

[0045] Specifically, ultraviolet / picosecond lasers are used for drilling, combined with dry plasma etching to modify the hole walls.

[0046] It is worth noting that laser drilling can effectively avoid microcracks, and combined with hole wall modification, it can improve the smoothness of the hole wall and the uniformity of metal filling.

[0047] In a second specific embodiment of step S1b of this application, a diamond-coated micro drill bit (30–100 μm in diameter) is used to drill holes in the glass substrate 1.

[0048] It is worth noting that diamond-coated miniature drills are suitable for processing high-hardness glass. To avoid glass breakage during drilling, the drill speed and feed rate need to be controlled. Operators can choose one of the two specific implementation methods described above for drilling operations, depending on their actual needs.

[0049] Furthermore, to reduce thermal stress and prevent microcracks, the coolant needs to be heated during drilling. Deionized water or water-based lubricant can be used as the coolant.

[0050] Preferably, a CNC drilling machine is used to achieve arrayed high-precision positioning, controlling the diameter of the through hole 11 within ±3μm and the positional accuracy within ±5μm.

[0051] Step S1c: Stress relief treatment of through holes.

[0052] Specifically, chemical strengthening (such as K) is performed after drilling. + (Exchange) or low-temperature annealing can eliminate micro-cracks at the hole edges and improve mechanical strength.

[0053] Step S2: Copper paste is printed on the front side 12 of the glass substrate 1 and vacuum suction is performed on the back side 13 of the glass substrate 1 simultaneously, so that the copper paste 15 fills the conductive path of the through hole 11.

[0054] The above step S2 specifically includes: Step S2a: Copper paste printing is performed on the front side 12 of the glass substrate 1 with through holes 11.

[0055] Specifically, such as Figure 3 As shown, a layer of specially made highly conductive copper paste 15 is printed on the front side 12 of the glass substrate 1 using screen printing technology, so that the copper paste 15 covers the opening area of ​​the through hole 11 and forms a continuous copper paste coating 14 on the surface of the glass substrate 1.

[0056] It is worth noting that copper paste 15 needs to have good fluidity and shrinkage to facilitate subsequent hole filling steps.

[0057] In some alternative embodiments, the thickness of the copper paste coating 14 should be controlled between 20-40 μm.

[0058] Understandably, keeping the copper coating thickness within this threshold of 14mm provides sufficient filler while avoiding excessive buildup.

[0059] Step S2b: While printing is in progress, the back side 13 of the glass substrate 1 is placed in a vacuum environment, and the back side 13 of the glass substrate 1 is simultaneously evacuated during the printing process to extract the air inside the through hole 11 in real time.

[0060] It is worth noting that under negative pressure, the printed copper paste 15 is rapidly drawn into the through-hole 11, achieving simultaneous printing and filling. By combining copper paste printing on the front side of the glass substrate with synchronous vacuum suction on the back side, dense metal filling, reliable interconnection, and void-free via metallization are achieved within the vias during the glass substrate. This directly solves the core problems of cumbersome via metallization processes, uneven filling, and poor interconnection reliability, replacing traditional electroplating or seed layer deposition methods, significantly reducing process complexity, improving metallization yield, and providing a high-reliability conductive path foundation for subsequent packaging.

[0061] Furthermore, multiple printings are required to ensure that the through-holes are filled and to ensure that the thickness of the screen-printed copper paste 3 is uniform.

[0062] In some preferred real-time methods, the vacuum level of the vacuum environment during the suction process is controlled between -0.08 and -0.1 MPa, and the printing speed needs to match the copper paste penetration rate to prevent clogging or air bubble residue.

[0063] Understandably, for through holes 11 with high aspect ratios, multiple printing processes combined with simultaneous vacuum suction can be used to ensure complete density.

[0064] Step S3: A first conductive layer 31 and a second conductive layer 32 are respectively prepared on the front side 12 and the back side 13 of the glass substrate 1.

[0065] It is understood that the first conductive layer 31 and the second conductive layer 32 are electrically connected through the conductive path formed by the copper paste 15 in the through hole 11.

[0066] The above step S3 specifically includes: Step S3a, as follows Figure 4 As shown, an ultra-thin copper sheet 3 is applied to the front side 12 of the glass substrate 1 while the copper paste 15 is not fully cured to form a continuous metal layer.

[0067] It should be noted that the copper sheet needs to have good ductility to accommodate curing shrinkage. Optionally, the thickness of the copper foil 3 can be controlled between 5 and 20 μm.

[0068] Preferably, the copper foil 3 is bonded under vacuum or reduced pressure.

[0069] It is worth noting that the vacuum / reduced pressure environment removes residual air from the interface in real time, preventing the interruption of the conductive path or the increase in resistance caused by trapped air bubbles, and avoiding interconnection failure problems caused by air bubbles in traditional bonding processes.

[0070] Step S3b, as follows Figure 5 As shown, the copper foil 3 and the copper adhesive 15 are tightly bonded together by hot pressing, thus forming the first conductive layer 31.

[0071] Specifically, the glass substrate 1 is placed entirely into a hot-press curing device, where the copper adhesive is cured under specific temperature and pressure conditions. The hot-pressing conditions can be selected as follows: processing for 30 to 90 minutes at a temperature of 150 to 220°C and a pressure of 0.5–2 MPa.

[0072] Understandably, the hot-pressing process allows the copper adhesive 15 to fully harden, forming a continuous conductive path within the through-hole 11. Simultaneously, the copper foil 3 firmly bonds to the glass substrate 1, forming a stable surface conductive layer. Furthermore, this application is not limited to using methods other than hot-pressing to prepare the first conductive layer 31 and the second conductive layer 32; in practice, the preparation process can be selected according to actual needs.

[0073] Step S3c, as follows Figure 5 As shown, copper paste printing is performed on the back side of the glass substrate 1, and copper foil 3 is then applied. Subsequently, as... Figure 6 As shown, the second conductive layer 32 is prepared by hot pressing before the copper paste is fully cured.

[0074] It should be noted that the preparation of the first conductive layer 31 and the second conductive layer 32 in this application includes, but is not limited to, hot pressing processes.

[0075] Step S4: Precision circuit construction.

[0076] Specifically, photoresist is coated on both the front and back sides of the glass substrate 1, and the circuit pattern is transferred after exposure and development. Then, a copper sheet is etched using a wet etching process, such as... Figure 7 As shown, remove the non-circuit areas and retain the required copper lines 16. Finally, remove the photoresist and clean the surface of the glass substrate 1.

[0077] Step S5: Complete the device installation of the first conductive layer 31 and the second conductive layer 32.

[0078] The above step S5 specifically includes: Step S5a: Print solder paste or eutectic solder at the pad location.

[0079] Step S5b, as follows Figure 8 and Figure 9 As shown, an LED chip 6 and a driver chip 7 are mounted on the first conductive layer 31 using a high-precision die bonder.

[0080] It is understandable that since there are two layers of circuitry on the glass substrate 1, each pixel needs to be driven by a separate driver chip 7 (i.e., IC), which can reduce the number of glass substrates and components.

[0081] Step S5b, as follows Figure 10As shown, components 8 are mounted on the second conductive layer 32 on the back side of the glass substrate 1 using dispensing or solder paste printing. The mounting of the back-side components is completed by curing or reflow soldering.

[0082] Understandably, component 8 includes capacitors and ports.

[0083] Step S6: Press the black adhesive layer 2 onto the front side 12 of the glass substrate 1.

[0084] It is understood that the gaps between all LED devices (i.e., driver chip 7 and LED chip 6) on the first conductive layer 31 are filled with black adhesive film by pressing the black adhesive layer 2 together. This application achieves optical isolation between pixels through the black adhesive layer 2, eliminates crosstalk between chips, and thus directly improves the contrast and color saturation of high-resolution Micro-LED displays, avoids light interference between adjacent pixels, and ensures the clarity and color accuracy of the displayed image, meeting the core requirements of high-resolution display scenarios.

[0085] In some preferred embodiments, such as Figure 14 As shown, the black adhesive film has a three-layer structure. A transparent adhesive layer 21 is attached to the side of the black adhesive layer 2 away from the glass substrate 1, and a plastic layer 22 is attached to the adhesive layer 21.

[0086] It should be noted that the plastic layer 22 is used to prevent the adhesive layer 21 from sticking to the flat mold 5 during subsequent hot pressing. Since the black adhesive layer 2 has a certain degree of fluidity during hot pressing, it can gradually fill the gaps in the LED devices under high temperature and negative pressure through the thrust of the airbag 9.

[0087] In conjunction with the above preferred embodiments, this application provides a specific embodiment of step S6, which includes: Step S6a: Cover the array surface formed by the glass substrate 1 and the installed LED devices with a pre-made black functional adhesive film (i.e., black adhesive layer 2).

[0088] Preferably, the thickness of the black adhesive layer 2 should be slightly thicker than the height of the LED device in the thickness direction of the glass substrate 1.

[0089] It is understandable that the thickness of the black adhesive layer 2 is adjusted in advance to prevent the LED beads from being damaged during the hot-press bonding process.

[0090] Step S6b, as follows Figure 11 As shown, the glass substrate 1 is placed in an airbag vacuum hot press, and the black adhesive layer 2 is arranged between the LED device on the first conductive layer 31 and the planar mold 5. The black adhesive layer 2 is placed face down on the planar mold 5.

[0091] Step S6c, as follows Figure 12As shown, under appropriate temperature, pressure and vacuum conditions, the black adhesive layer 2 is softened and filled into the gap between the LED chip 6 and the driver chip 7 under the pressure of the airbag 9. During the pressing process, the adhesive layer 21 on the black adhesive layer 2 is squeezed out and discharged from the black adhesive between itself and the LED device.

[0092] It is worth noting that the black adhesive layer 2, combined with hot pressing, has good light-shielding properties after molding, ensuring that the gaps between LED devices are completely filled without voids, avoiding lateral light leakage, thereby strengthening the optical isolation between pixels and further improving display contrast and color saturation.

[0093] Step S7: Attach the glass cover plate 4 to the glass substrate 1 to complete the encapsulation.

[0094] Specifically, step S7 includes: Step S7a: Remove the plastic layer 22 from the surface of the black adhesive layer 2, and attach the glass cover plate 4 with optical structure to the black adhesive layer 2.

[0095] Step S7b: The glass cover plate 4, the black adhesive layer 2 and the glass substrate 1 are bonded together by hot pressing.

[0096] Specifically, the integral substrate obtained in the aforementioned steps is placed in an airbag vacuum hot press, and under appropriate temperature and vacuum conditions, the pressure applied by the airbag 9 is used to activate the adhesion of the transparent adhesive layer 21. Figure 15 and Figure 16 As shown, the glass cover plate 4, the black adhesive layer 2, and the glass substrate 1 are tightly bonded together.

[0097] It is worth noting that in the above steps, the glass cover plate and the black adhesive film are permanently bonded together by vacuum hot pressing to form a fully sealed protective layer to resist moisture, dust and mechanical impact. At the same time, the cover plate surface integrates optical structures to optimize display performance.

[0098] Step S7c: The substrate structure obtained in the previous steps is formed by baking and curing. Figure 17 As shown, this is an LED display device.

[0099] In some alternative implementations, the baking curing should be performed at 120 to 150°C for 3-4 hours.

[0100] Fourthly, this application provides a packaging system for an LED packaging structure, comprising: an opening module, a through-hole metallization module, a conductive layer preparation module, a device mounting module, and a bonding and packaging module; wherein, The system includes: an opening module for creating through holes 11 on the glass substrate 1; a through-hole metallization module for printing copper paste on the front side 12 of the glass substrate 1 to form a copper paste coating 14 and simultaneously vacuum-suctioning the back side 13 of the glass substrate 1 so that the copper paste 15 fills the through holes 11 to form a conductive path; a conductive layer preparation module for preparing a first conductive layer 31 and a second conductive layer 32 on the front side 12 and back side 13 of the glass substrate 1, respectively, so that the first conductive layer 31 and the second conductive layer 32 are electrically connected through the copper paste 15 in the through holes 11; a device mounting module for mounting devices on the first conductive layer 31 and the second conductive layer 32; and a bonding and encapsulation module for bonding a glass cover plate 4 to the glass substrate 1 to complete the encapsulation.

[0101] The functions of each module in the above packaging system correspond to the steps in the above packaging method embodiments, and their functions and implementation processes will not be described in detail here.

[0102] In summary, the packaging method of this application achieves dense metal filling, reliable interconnection, and no voids within the vias during the metallization process of the glass substrate vias through a process of "copper paste printing combined with synchronous vacuum suction". Simultaneously, a dual vacuum hot-pressing process (including black adhesive lamination and glass cover plate bonding) is used to achieve precise integrated bonding of the glass cover plate, black adhesive film, and substrate, ensuring uniform overall thickness. Furthermore, this application utilizes the high optical absorption characteristics of the black adhesive film to precisely fill the gaps between LED chips and completely block light crosstalk between adjacent pixels, significantly improving display contrast and color saturation.

[0103] Fourthly, this application provides an LED packaging structure, which is prepared by the above-described packaging method. Since this LED packaging structure employs all the technical solutions of all the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated upon here.

[0104] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0105] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0106] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for metallizing through-holes in a glass substrate for LED packaging structures, characterized in that, include: Copper paste is printed on the front side (12) of the glass substrate (1) and vacuum suction is performed on the back side (13) of the glass substrate (1) simultaneously so that the copper paste (15) fills the through holes (11) on the glass substrate (1).

2. A packaging method for an LED packaging structure, characterized in that, include: Copper paste is printed on the front side (12) of the glass substrate (1) with through holes (11) to form a copper paste coating (14), and the back side (13) of the glass substrate (1) is vacuumed simultaneously so that the copper paste (15) fills the through holes (11) to form a conductive path. A first conductive layer (31) and a second conductive layer (32) are respectively prepared on the front side (12) and the back side (13) of the glass substrate (1) so that the first conductive layer (31) and the second conductive layer (32) are electrically connected through the copper paste (15) in the through hole (11). After the device with the first conductive layer (31) and the second conductive layer (32) is installed, the glass cover plate (4) is attached to the glass substrate (1) to complete the encapsulation.

3. The packaging method as described in claim 2, characterized in that, Before attaching the glass cover plate (4) to the glass substrate (1) to complete the encapsulation, the method further includes: pressing the black adhesive layer (2) onto the front side (12) of the glass substrate (1) so that the gaps between all LED devices on the first conductive layer (31) are filled with black adhesive film.

4. The packaging method as described in claim 3, characterized in that, The step of pressing the black adhesive layer (2) onto the front side (12) of the glass substrate (1) includes: The black adhesive layer (2) is arranged between the LED device and the planar mold (5) on the first conductive layer (31), and the thickness of the black adhesive layer (2) is higher than the height of the LED device in the thickness direction of the glass substrate (1). The black adhesive layer (2) is pressed onto the glass substrate (1).

5. The packaging method as described in claim 3, characterized in that, The process of attaching the glass cover plate (4) to the glass substrate (1) to complete the encapsulation includes: attaching the glass cover plate (4) to the adhesive layer (21) on the surface of the black glue layer (2), and combining the glass cover plate (4), the black glue layer (2) and the glass substrate (1).

6. The packaging method as described in claim 2, characterized in that, The process of applying copper paste printing on the front side (12) of the glass substrate (1) and simultaneously performing vacuum suction on the back side (13) of the glass substrate (1) includes: A continuous copper paste coating (14) is printed on the front side (12) of the glass substrate (1), and the copper paste coating (14) covers the opening area of ​​the through hole (11). The back side (13) of the glass substrate (1) is placed in a vacuum environment, and the back side (13) of the glass substrate (1) is simultaneously evacuated during the printing process.

7. The packaging method as described in claim 2, characterized in that, The fabrication of a first conductive layer (31) and a second conductive layer (32) on the front side (12) and back side (13) of the glass substrate (1) respectively includes: Copper foil (3) is attached to the front (12) and back (13) of the glass substrate (1) while the copper paste (15) is not fully cured, and the copper foil (3) is combined with the copper paste (15) to form the first conductive layer (31) and the second conductive layer (32).

8. The packaging method as described in claim 2, characterized in that, The device mounting on the first conductive layer (31) and the second conductive layer (32) includes: A circuit is constructed on the first conductive layer (31) and the second conductive layer (32); An LED chip (6) and a driver chip (7) are mounted on the first conductive layer (31). Components (8) are mounted on the second conductive layer (32).

9. A packaging system for an LED packaging structure, characterized in that, include: An opening module is used to open through holes (11) on a glass substrate (1). The through-hole metallization module is used to print copper paste on the front side (12) of the glass substrate (1) and simultaneously perform vacuum suction on the back side (13) of the glass substrate (1) so that the copper paste (15) fills the through hole (11) to form a conductive path. A conductive layer preparation module is used to prepare a first conductive layer (31) and a second conductive layer (32) on the front side (12) and back side (13) of the glass substrate (1), respectively, so that the first conductive layer (31) and the second conductive layer (32) are electrically connected through the copper paste (15) in the through hole (11). A device mounting module for mounting devices on the first conductive layer (31) and the second conductive layer (32); A bonding and encapsulation module is used to bond the glass cover plate (4) to the glass substrate (1) to complete the encapsulation.

10. An LED packaging structure, characterized in that: The LED packaging structure is prepared by the packaging method described in any one of claims 2-8.

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