Array type flexible electronic device packaging and electrode leading-out method

Abstract

The invention relates to the field of photoelectric device manufacturing, and discloses an array type flexible electronic device packaging and electrode leading-out method. Comprising the following steps: preparing a flexible electronic device array on a substrate, forming a top electrode layer on the surface of the flexible electronic device array, and electrically isolating a single flexible electronic device; coating a sealant on the periphery of the active region of each flexible electronic device and on the inner side of the isolation channel to form a closed pre-sealing box dam; arranging a temporary protection layer in an area, corresponding to a preset windowing position, on the top electrode layer; removing the film layer at the preset windowing position through laser to expose the top electrode layer; and electrode leading-out is carried out in the exposed top electrode layer area, and packaging and electrode leading-out of the array type flexible electronic device are completed. According to the invention, efficient full-page packaging and electrode extraction of the array flexible device are realized, excellent air tightness of the edge of the device and electrode points is ensured through a multi-sealing structure, and integrity of a functional layer and packaging is ensured by adopting lossless laser processing.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic device manufacturing technology, and in particular to an array-type flexible electronic device packaging and electrode lead-out method. Background Technology

[0002] Perovskite solar cells, as a representative of third-generation photovoltaic technology, have attracted widespread attention from academia and industry due to their outstanding advantages such as high photoelectric conversion efficiency, low material cost, and solution-processability. Flexible perovskite photovoltaic devices, in particular, have shown enormous application potential in emerging fields such as wearable electronic devices, building-integrated photovoltaic systems, and power supplies for IoT node devices. For example, in passive IoT devices that do not require external power, there is an urgent need to develop flexible self-powered solutions with high environmental reliability, long lifespan, and moderate deformation capacity.

[0003] However, despite significant progress in the laboratory stage, flexible perovskite devices still face a series of severe challenges in engineering aspects such as packaging and electrode lead-out for practical applications, which seriously restricts their commercialization process. Existing technologies mainly suffer from the following shortcomings: First, it is difficult to balance the reliability and sealing of electrode lead-out: Currently, the common packaging method encapsulates the functional layer between a flexible substrate and a barrier layer, with electrodes typically led out directly from the packaging edge. This method creates continuous linear gaps at the packaging interface, resulting in weak mechanical bonding, easy delamination during bending, and providing direct permeation channels for moisture and oxygen in the environment, leading to rapid degradation of the perovskite active layer and severely affecting the long-term stability and lifespan of the device. Second, the flexible compatibility of the packaging structure is insufficient: In pursuit of high barrier performance, existing packaging solutions often tend to use relatively rigid multilayer stacked structures or hard barrier materials. Under repeated bending, stretching, or rolling mechanical stress, these are prone to problems such as interface delamination, barrier layer cracking, or electrode breakage, making it difficult to meet the stringent dynamic reliability requirements of flexible electronic products. Third, large-scale production is inefficient and costly: Existing packaging processes are mostly based on independent packaging of individual devices, which is complex, time-consuming, and has low material utilization. This discrete packaging method is difficult to be effectively compatible with large-area, continuous roll-to-roll production, resulting in high large-scale production costs and becoming one of the main bottlenecks to industrialization. Fourth, post-processing cutting leads to compromised seal integrity: After device fabrication and preliminary packaging are completed on a large-area substrate, cutting is usually required to obtain individual device units. This mechanical cutting process inevitably damages the integrity of the package edges, creating new unsealed cuts that expose the device side interfaces directly to the environment, reintroducing weak points for water and oxygen erosion.

[0004] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide an array-type flexible electronic device packaging and electrode lead-out method, which aims to solve the problems of unreliable contact and poor stability of existing electrode lead-out methods when fabricating flexible electronic devices on a whole board.

[0006] The technical solution of the present invention is as follows: This invention provides a method for packaging and leading out electrodes of an array-type flexible electronic device, the method comprising the following steps: S1. Fabricate a flexible electronic device array on a substrate, then form a common top electrode layer on the surface of the flexible electronic device array, and then perform electrical isolation of individual flexible electronic devices. S2. Apply sealant to the inner side of the isolation channel around the active area of ​​each flexible electronic device to form a closed pre-sealed dam. S3. A temporary protective layer is provided on the top electrode layer in the area corresponding to the preset window position; S4. Remove the film layer at the preset window opening position using a laser device to expose the top electrode layer; S5. Electrode leads are made in the exposed top electrode layer region to complete the packaging and electrode lead-out of the array-type flexible electronic device.

[0007] Optionally, the temporary protective layer is formed by coating, and the material of the temporary protective layer is a material that can be removed by laser.

[0008] Optionally, the temporary protective layer is an attached laser-release pad.

[0009] Optionally, the method for leading out the electrode includes one of the following: coating and curing low-temperature conductive silver paste, welding metal foil, connecting prefabricated conductive terminals, coating and curing anisotropic conductive adhesive film, wire bonding, and pad bonding.

[0010] Optionally, the shape of the pre-sealed dam matches the outer shape of the active area of ​​the flexible electronic device, and its width is smaller than the width of the isolation trench.

[0011] Optionally, before removing the film layer at the preset window opening position by laser, the method further includes the following steps: After completing steps S2 and S3, an encapsulating film and a barrier film are sequentially covered on the surface of the conductive substrate layer and the top electrode layer of the overall structure, and then laminated.

[0012] Optionally, the electrical isolation may employ an infrared nanosecond laser.

[0013] Optionally, the laser device includes one of an ultraviolet picosecond laser device and an ultraviolet femtosecond laser device.

[0014] Optionally, the flexible electronic device includes one of flexible perovskite solar cells, flexible photodetectors, and flexible sensors.

[0015] The present invention has the following beneficial effects: This invention provides a method for packaging and leading out electrodes for array-type flexible electronic devices. Compared with existing technologies, it achieves the following significant advantages: First, it significantly improves production efficiency and scalability. This invention employs a "whole-plate preparation, whole-plate packaging" process, enabling simultaneous and integrated packaging and electrode leading out of hundreds or even thousands of flexible electronic device units arranged in an array on a substrate. This method completely changes the inefficient traditional method of packaging individual devices one by one, greatly simplifying the process flow, reducing production steps and time, significantly improving production efficiency and capacity. Furthermore, it is highly compatible with large-area, continuous roll-to-roll (R2R) or sheet-to-sheet (S2S) manufacturing processes, providing a practical and feasible technical path for the low-cost, large-scale production of flexible electronic devices. Second, the reliability and long-term stability of the device packaging are fundamentally enhanced: This invention combines an original "edge pre-sealed dam" with "laminated packaging." This system not only effectively eliminates water and oxygen permeation channels from the packaging edges and electrode exit points, but also ensures the sealing integrity of the device under repeated bending through structural design. This results in each individual flexible electronic device unit possessing excellent environmental barrier performance and hermeticity, laying a solid foundation for its long-term reliable operation and extended service life. Third, precision machining and device integrity are perfectly balanced: The core processing steps of this invention (such as electrical isolation) preferably employ infrared nanosecond laser processing technology. The processing mechanism of this type of laser is "cold processing," with a very small heat-affected zone (HAZ) and almost no heat diffusion. This characteristic ensures that when removing the functional layer, opening the electrode window, and cutting and separating the units, the laser energy is strictly limited to the target processing area, effectively avoiding secondary damage such as thermal damage, microcracks, or delamination to the heat-sensitive perovskite active layer, flexible polymer substrate, and the formed packaging structure during the processing. This allows for high-precision, high-degree-of-freedom patterning while preserving the intrinsic properties of the functional materials and the integrity of the packaging structure to the greatest extent possible, ensuring the high performance and high yield of the final device. Attached Figure Description

[0016] Figure 1 This is a schematic flowchart illustrating the array-type flexible electronic device packaging, electrode lead-out, and single-unit separation method in a preferred embodiment of the present invention. Detailed Implementation

[0017] This invention provides a method for packaging and leading out electrodes for an array-type flexible electronic device. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0018] In the industrialization of novel electronic devices such as flexible perovskite solar cells, encapsulation and electrode lead-out technologies are crucial factors determining their reliability, lifespan, and feasibility for large-scale production. Currently, the mainstream technological approach in this field mainly draws on the encapsulation model of mature crystalline silicon photovoltaic modules, making adaptive adjustments based on the flexibility characteristics. However, a series of fundamental technological bottlenecks remain to be overcome.

[0019] 1. Limitations of mainstream packaging structures and large-scale production models Currently, the industry commonly uses a "sandwich" lamination structure for packaging: a flexible substrate is used as the base, covered with a perovskite active functional layer, and then adhesive films (such as POE or EVA) and high-barrier films are laminated on top and bottom to achieve overall encapsulation and protection of the core active area. For electrode lead-out, conductive tape is mainly used to attach or weld metal busbars to conduct current from the packaging edge.

[0020] However, this packaging and lead-out model, which originates from a single large-area device, has revealed serious inadequacies when addressing the emerging demand for high-density array-type flexible devices. Specifically, to meet the needs of wearable electronics, IoT distributed power supply, and other applications for small-size, lightweight, and deformable devices, the industry trend is to fabricate hundreds or thousands of independent small device units on a large-size flexible substrate at once. If the traditional discrete model of "fabrication-packaging a single device" is used, it will result in extremely low production efficiency, high costs, and an inability to achieve economies of scale. Therefore, the integrated manufacturing route of "full-board fabrication followed by cutting and separation" has become an inevitable choice. But it is precisely this efficient production model that renders traditional electrode lead-out methods completely ineffective: First, after completing the full-board packaging and cutting the units, the size of each independent device is tiny, and the electrode lead-out area is limited, far smaller than the minimum reliable attachment area required for conductive tape or busbars; second, the device units are arranged closely to improve the utilization rate of substrate materials, leaving insufficient space to accommodate the wiring and stacking of traditional lead-out structures. Therefore, developing a novel electrode lead-out scheme suitable for high-density arrayed flexible devices and compatible with efficient whole-plane fabrication processes has become a core challenge to promote the practical application of this technology.

[0021] 2. Inherent defects of existing electrode extraction methods Even for individual devices, the current mainstream conductive tape lead-out technology itself has many inherent defects, making it difficult to meet the high reliability and long lifespan requirements of flexible perovskite devices: (1) Poor reliability of the contact interface: The contact between the conductive tape and the vapor-deposited thin film electrode of the device mainly relies on the physical adhesion of the adhesive to achieve contact, which makes it difficult to form a stable, low-resistance ohmic contact. During the service of the device, especially under stress conditions such as repeated bending, twisting or temperature cycling, the contact interface is prone to micro-slippage and delamination, which leads to a sharp increase in contact resistance, unstable signal or even instantaneous open circuit.

[0022] (2) Insufficient long-term environmental stability: The organic adhesives in conductive tapes are prone to aging, cracking, or chemical migration under long-term light exposure and humid heat. This will not only directly lead to the decay of conductivity, but the migrated substances may also penetrate into the sensitive perovskite active layer, accelerating its performance degradation and seriously affecting the overall lifespan of the device.

[0023] (3) Challenges in process precision and integration compatibility: Precisely attaching sized conductive tapes to the electrode points of micro-devices at the millimeter or even sub-millimeter scale places extremely high demands on the alignment accuracy and process stability of the mounting equipment, making yield control difficult. In addition, the tape itself has a certain thickness and steps, which can easily lead to gaps or voids at the edges of the tape during subsequent local sealing protection, becoming weak points for water and oxygen intrusion and compromising the integrity of the overall package.

[0024] 3. Inherent risks of post-lamination processing To expose the electrodes, a window must be created at a specific location after the overall lamination encapsulation is completed. Currently, the commonly used post-windowing process, such as laser ablation, is a destructive process. When a high-energy laser locally burns through the barrier layer and the encapsulant film, the resulting thermal stress impacts and weakens the bonding strength of the encapsulation interface around the windowed area, easily inducing microscopic delamination between the electrode and the functional layer or between different encapsulation layers. This initial defect will further expand under subsequent thermodynamic loads, ultimately leading to encapsulation failure. Therefore, the "post-lamination windowing" process itself is a critical step that introduces reliability risks.

[0025] In summary, existing technologies face the challenge of large-scale electrode lead-out failures as they evolve from "single large devices" to "arrayed small devices." Furthermore, their inherent electrode lead-out methods suffer from serious deficiencies in contact reliability, long-term stability, and compatibility with packaging processes. Coupled with the risk of damage to packaging integrity caused by the post-lamination windowing process, these factors collectively constitute the fundamental technical obstacles hindering the industrialization of high-performance, high-reliability arrayed flexible perovskite devices. This invention is proposed to systematically address these problems.

[0026] Based on this, embodiments of the present invention provide a method for packaging and leading out electrodes of an array-type flexible electronic device, the method comprising the following steps: S1. Fabricate a flexible electronic device array on a substrate, then form a common top electrode layer on the surface of the flexible electronic device array, and then perform electrical isolation of individual flexible electronic devices. S2. Apply sealant to the inner side of the isolation channel around the active area of ​​each flexible electronic device to form a closed pre-sealed dam. S3. A temporary protective layer is provided on the top electrode layer in the area corresponding to the preset window position; S4. Remove the film layer at the preset window opening position using a laser to expose the top electrode layer; S5. Electrode leads are made in the exposed top electrode layer region to complete the packaging and electrode lead-out of the array-type flexible electronic device.

[0027] The core innovation of the array-type flexible electronic device packaging and electrode lead-out method provided in this invention lies in proposing a disruptive reverse process flow of "first overall packaging, then separating individual cells". Specifically, after the device fabrication is completed, this invention does not package individual devices one by one, but performs a one-time, synchronous overall packaging and electrode lead-out process on hundreds or even thousands of battery cells arranged in an array on a large-size flexible substrate. This fundamental process reconstruction greatly simplifies and integrates the cumbersome steps of traditional discrete packaging, achieving a leapfrog improvement in production efficiency and large-scale production capacity, and providing a new technical paradigm for the large-scale, low-cost manufacturing of flexible electronic devices.

[0028] This method significantly improves production efficiency while systematically addressing the long-term reliability bottleneck faced by flexible electronic devices, especially perovskite solar cells, through a series of collaboratively designed sub-steps: First, regarding encapsulation reliability: This invention creatively combines "edge pre-sealing damming" with "lamination encapsulation." A robust physical and chemical barrier is formed at the device edge. This barrier, together with the main encapsulation layer, constitutes a three-dimensional, redundant sealing system, completely blocking the edges and electrode leads where moisture and oxygen are most likely to penetrate, significantly improving the overall environmental barrier capability and long-term operational stability of the device. Second, regarding electrode protection and high-quality windowing: The temporary protective layer set in the preset windowing area in step S3 plays a crucial bridging role. During lamination, it effectively isolates the encapsulation film (such as POE film) from direct contact with the precision-deposited top electrode below, preventing adhesion or damage that may occur under high temperature and high pressure conditions. During laser windowing in step S4, the temporary protective layer precisely absorbs and dissipates laser energy, ensuring that the laser removal process acts only on the target film layer without causing thermal shock or mechanical abrasion effects on the underlying electrode interface. This achieves high-quality, low-damage electrode exposure, creating clean and intact interface conditions for subsequent reliable electrode extraction. Third, regarding the universality and application advantages of the solution: The method described in this invention has broad compatibility with flexible substrate types (such as PET, PI, etc.) and specific electronic device types (such as perovskite, organic photovoltaic cells, etc.). Its process advantages are particularly prominent in the fabrication of large-size substrates and high-density arrayed devices. This method perfectly adapts to the industry trend of fabricating numerous micro-devices at once through large-area processes such as slot coating and vapor deposition, solving the core contradiction that traditional electrode extraction methods cannot be implemented in micro-unit, high-integration layouts. It provides key manufacturing process support for the application of flexible electronics technology in a wide range of fields such as wearable devices, building-integrated photovoltaics, and IoT power supply.

[0029] In summary, the technical solutions defined in the embodiments of the present invention have achieved significant progress in three aspects: production efficiency, packaging reliability, and process applicability through fundamental innovation in the process flow and collaborative design of key steps, systematically overcoming the inherent defects of the prior art.

[0030] This invention provides a method for packaging, electrode lead-out, and individual device separation of an array-type flexible electronic device, the detailed process of which is as follows: Figure 1 As shown, the specific steps include: Step S1, Overall Fabrication and Electrode Formation: On a flexible substrate (e.g., a 300mm × 300mm PET substrate), multiple single-junction perovskite solar cell functional layers arranged in a regular array are fabricated using large-area film deposition processes such as slot coating and vacuum evaporation. Subsequently, a common metal top electrode layer, such as a silver (Ag) or gold (Au) electrode, is formed on the entire substrate surface using a mask-assisted evaporation process.

[0031] Step S2, Cell Electrical Isolation (First Laser Processing): Using a first laser device (e.g., an infrared nanosecond laser), all functional layer materials and the metal top electrode layer in the area surrounding the planned cutting path of each battery cell are precisely removed, forming an isolation trench around the active area of ​​each battery cell. This step achieves electrical isolation between battery cells and reserves space for subsequent edge sealing structures.

[0032] Step S3: Constructing an edge pre-sealed dam: Around the active area of ​​each battery cell, inside the isolation trench formed in step S2, a ring of sealant (such as epoxy resin, UV-curable adhesive, etc.) is applied using a high-precision dispensing device to form an annular pre-sealed dam. This dam constitutes the first edge sealing structure of the encapsulation system.

[0033] Step S4: Set a temporary protective layer for the windowed area: On the metal top electrode layer, a temporary protective layer is set for the preset windowed area where the electrode will be led out later. This temporary protective layer can be formed by coating a functional material (such as a light-absorbing polymer) that can be effectively removed by a laser of a specific wavelength, or it can be achieved by precisely attaching a laser release liner. Its main function is to protect the underlying electrode during the subsequent lamination process and to provide a clean release interface for the laser windowing.

[0034] Step S5, Full-Panel Lamination and Encapsulation: On the front and back sides (PET substrate side) of the completed full-panel substrate, a sealing film (e.g., polyolefin elastomer POE film) and a high water and oxygen barrier film (e.g., Al2O3 / PET composite barrier film) are sequentially laminated. Then, it is placed in a vacuum laminator and laminated under specific temperature, pressure, and vacuum conditions. During lamination, the sealing film melts and flows, fusing with the pre-sealed dam from step S3, ultimately forming a complete sandwich-style integral encapsulation structure that encapsulates all battery cells together with the upper and lower barrier films and the substrate.

[0035] Step S6: Laser windowing to expose the electrode: Using a second laser device (e.g., an ultraviolet picosecond laser), the windowed area preset in step S4 is precisely processed. The laser sequentially removes the barrier film, encapsulating film, and temporary protective layer above the area, thereby cleanly and undamagedly exposing the underlying metal top electrode layer, forming a window for the electrode to extend.

[0036] Step S7, Electrode Lead-out and Local Secondary Sealing: Electrode lead-out is performed on the metal top electrode area exposed in Step S6. Specifically, this can be achieved by spot-applying and low-temperature curing conductive silver paste, ultrasonically welding metal foil (such as copper foil), or crimping pre-fabricated conductive terminals (such as Pogo Pin connectors), to achieve a reliable electrical connection with external circuits or adjacent devices. Next, a local sealing material (such as silicone gel, polyurethane adhesive, or UV-curable adhesive) is applied to the windowed area where the electrode lead-out is completed and its surroundings, completely covering the exposed electrode, lead wire, and part of the surrounding encapsulation layer. This local seal, in conjunction with the edge pre-sealing dam formed in Step S3, constitutes a robust secondary seal for the electrode lead-out point, completely blocking the environmental intrusion channel at this location.

[0037] Step S8, Precision Cutting and Separation of Individual Cells (Third Laser Processing): Finally, using a third laser device (preferably a picosecond ultraviolet laser with an extremely small heat-affected zone), a final precision cut is performed along a planned path outside the sealant dam formed in step S3, around the periphery of each cell. This step separates the entire substrate, which has been fully encapsulated and has its electrodes extended, into multiple independent, fully encapsulated flexible perovskite solar cell individual devices. Because the cutting path is designed within the sealant area, it ensures that all edges of each individual cell are completely encapsulated by sealant after separation, with no active material or interface exposed.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0039] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. An array-type flexible electronic device packaging and electrode lead-out method, characterized by, The method comprises the following steps: S1, preparing an array of flexible electronic devices on a substrate, forming a common top electrode layer on the surface of the array of flexible electronic devices, and then performing electrical isolation of individual flexible electronic devices; S2, applying a sealant to the inner side of the isolation channel at the periphery of the active area of each flexible electronic device to form a closed pre-sealing dam; S3, setting a temporary protective layer on the top electrode layer corresponding to the area of the pre-set windowing position; S4, removing the film layer at the pre-set windowing position by a laser device to expose the top electrode layer; S5, electrode lead-out is performed on the exposed top electrode layer area to complete the packaging and electrode lead-out of the array flexible electronic device.

2. The array-type flexible electronic device package and electrode lead-out method according to claim 1, wherein The temporary protective layer is formed by coating, and the material of the temporary protective layer is a material that can be removed by laser.

3. The arrayed flexible electronic device package and electrode lead-out method according to claim 1, wherein The temporary protective layer is a laser stripping liner.

4. The arrayed flexible electronic device package and electrode lead-out method according to claim 1, wherein The electrode lead-out method comprises one of the following: coating and curing low-temperature conductive silver paste, welding metal foil, connecting pre-made conductive terminals, coating and curing anisotropic conductive adhesive film, wire bonding, and solder pad.

5. The arrayed flexible electronic device package and electrode lead-out method according to claim 1, wherein The shape of the pre-sealing dam matches the shape of the periphery of the active area of the flexible electronic device, and the width is less than the width of the isolation channel.

6. The arrayed flexible electronic device package and electrode lead-out method according to claim 1, wherein Before removing the film layer at the pre-set windowing position by laser, the method further comprises the following steps: After completing the conductive substrate layer surface and the top electrode layer surface of the whole plate structure of steps S2 and S3, the surface is sequentially covered with packaging adhesive film and barrier film for lamination.

7. The arrayed flexible electronic device package and electrode lead-out method according to claim 1, wherein The device used for electrical isolation comprises an infrared nanosecond laser.

8. The arrayed flexible electronic device package and electrode lead-out method according to claim 1, wherein The laser device comprises one of the following: an ultraviolet picosecond laser device and an ultraviolet femtosecond laser device.

9. The arrayed flexible electronic device package and electrode lead-out method according to claim 1, wherein The flexible electronic device comprises one of the following: a flexible perovskite solar cell, a flexible photodetector, and a flexible sensor. The temporary protective layer is formed by coating, and the material of the temporary protective layer is a material that can be removed by laser. The temporary protective layer is a laser stripping liner. The electrode lead-out method comprises one of the following: coating and curing low-temperature conductive silver paste, welding metal foil, connecting pre-made conductive terminals, coating and curing anisotropic conductive adhesive film, wire bonding, and solder pad. The shape of the pre-sealing dam matches the shape of the periphery of the active area of the flexible electronic device, and the width is less than the width of the isolation channel. Before removing the film layer at the pre-set windowing position by laser, the method further comprises the following steps: After completing the conductive substrate layer surface and the top electrode layer surface of the whole plate structure of steps S2 and S3, the surface is sequentially covered with packaging adhesive film and barrier film for lamination. The device used for electrical isolation comprises an infrared nanosecond laser. The laser device comprises one of the following: an ultraviolet picosecond laser device and an ultraviolet femtosecond laser device. The flexible electronic device comprises one of the following: a flexible perovskite solar cell, a flexible photodetector, and a flexible sensor.

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