A flexible optoelectronic device packaging method based on multifunctional ultrathin glass

Abstract

The application discloses a flexible optoelectronic device packaging method based on multifunctional ultrathin glass, which uses ultrathin glass (UTG) with a thickness of 50-210 mu m as a core substrate, and constructs a symmetrical packaging structure through double-sided functional modification; through a non-periodic multilayer interference film, a patterned intermittent physical vapor deposition metal layer and a modulus gradient polymer buffer layer, 300-1000 nm waveband antireflection, 8-13 mu m atmospheric window radiation refrigeration and high-performance electrical connection are realized; the back metal pattern is optimized to separate out positive and negative electrode dedicated lead-through channels; and a ring of barrier glue cofferdam is arranged in the inner side of the external metal weld to serve as a secondary moisture interception barrier, and through a low-temperature welding process, a double-dense edge sealing network is constructed while avoiding thermal damage. The application not only reduces thermal mismatch stress, but also reduces water and oxygen transmission rate to 10 ‑5 g / m 2 / day level, and greatly improves the long-term working stability and mechanical reliability of flexible perovskite, organic and flexible silicon solar cells and other devices in complex environments.

Description

Technical Field

[0001] This invention relates to the field of flexible electronic device packaging technology, and more specifically to a flexible optoelectronic device packaging method based on multifunctional ultrathin glass. Background Technology

[0002] With the rapid development of flexible electronics technology, especially flexible perovskite solar cells (PSCs) and organic solar cells (OSCs), high-performance packaging technology has become a core bottleneck determining the industrialization process of these devices. These optoelectronic devices are extremely sensitive to moisture and oxygen in the environment, requiring the packaging material to have a water-oxygen permeability (WVTR) of 10. -6 g / m 2 The number of days is on the order of magnitude. Currently, the main technical routes used in the flexible packaging field include organic polymer film encapsulation and thin-film encapsulation (TFE) technology. Commonly used organic polymer films include polyethylene terephthalate (PET), polyimide (PI), and polyethylene naphthalate (PEN). Although these materials have excellent flexibility and low cost advantages, their large intermolecular gaps result in poor water and oxygen barrier properties, with WVTR typically only reaching 10. -1 g / m 2The current per-day capacity cannot meet the requirements of long-life optoelectronic devices. TFE technology typically employs atomic layer deposition (ALD) or plasma-enhanced chemical vapor deposition (PECVD) to alternately stack inorganic barrier layers and organic buffer layers. However, this process is costly, inefficient, and the inorganic films are prone to microcracks during repeated bending, leading to rapid failure of encapsulation performance. While traditional glass encapsulation uses rigid glass with absolute water and oxygen barrier properties, its rigidity makes it unsuitable for flexible applications. In addition, existing flexible packaging solutions generally have the following drawbacks: 1) Severe lateral water and oxygen penetration at the edges: Traditional organic encapsulants are exposed to the external environment at the edges for a long time, and water and oxygen can easily diffuse and penetrate into the device from the adhesive layer interface; 2) Electrode lead-out disrupts barrier continuity: When the positive and negative electrodes inside the device are led out of the package, conventional wire lead-out methods will cause tiny gaps at the packaging interface, which become "highways" for water and oxygen intrusion; 3) Welding thermal damage: Conventional metal weld edge sealing or crystalline silicon cell main grid welding often requires high temperatures above 180°C, which will cause irreversible damage to the perovskite layer and organic active layer with low thermal degradation threshold; 4) Lack of thermal management capability and stress mismatch: The heat generated by flexible optoelectronic devices under light is difficult to dissipate, and heat accumulation will lead to the evolution of organic layer morphology or perovskite phase transition, resulting in a sharp drop in efficiency. Existing thin films lack active thermal management functions; In addition, the difference in thermal expansion coefficient between the encapsulation layer and the flexible optoelectronic device substrate is significant. When the ambient temperature fluctuates or mechanical bending occurs, huge shear stress will be generated at the interface, leading to interlayer delamination. Furthermore, while silicon itself is stable, its mechanical strength drops drastically when silicon wafers are thinned to below 100 μm to achieve flexibility, making them highly susceptible to microcracks during encapsulation or bending. Existing polymer encapsulation films (such as EVA and POE) have low modulus, making it difficult to provide sufficient physical support for thin silicon wafers under external impact; while directly using rigid glass encapsulation would negate its flexibility advantage. Therefore, developing a flexible encapsulation solution that possesses superior water and oxygen barrier properties, excellent flexibility, optical and thermal management capabilities, and the ability to effectively suppress silicon wafer breakage is a pressing technical problem that needs to be solved in this field. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing flexible packaging materials, such as poor water and oxygen barrier properties, lack of active thermal management functions in polymer films, and susceptibility to thermal stress breakage and mechanical microcracks in thin-film silicon wafers and thin-film batteries during packaging and use. This invention provides a flexible packaging method based on multifunctional ultrathin glass. The invention aims to solve the technical challenges of achieving high barrier performance in flexible optoelectronic devices while simultaneously ensuring radiative cooling, highly reliable electrical connections, and effective stress buffering.

[0004] The objective of this invention is achieved through the following technical solution: This invention discloses a method for packaging flexible optoelectronic devices based on multifunctional ultrathin glass, comprising the following steps: Step 1: Select ultra-thin glass with a thickness of 50-210μm as the encapsulation substrate, and perform surface cleaning and surface activation treatment in sequence to enhance surface energy; Step 2: A non-periodic HfO2 / MgF2 multilayer interference film is prepared on the first surface of the ultrathin glass by thin film deposition process, and then annealed to induce microcrystallization of the film and release surface stress. Step 3: On the second surface of the ultrathin glass, multiple metal electrode layers are continuously deposited in a single vacuum cycle using physical vapor deposition. During the deposition process, an intermittent deposition protocol is executed to control thermal stress, and the metal layers are patterned using masking or laser patterning processes to separate dedicated conductive channels for the positive and negative electrodes of the device and peripheral metal weld beads. Step 4: On the inner side of the outer metal weld bead, a barrier adhesive containing moisture-absorbing components is set up using a precision dispensing process to serve as a secondary moisture interception barrier. Step 5: Prepare a liquid polymer resin containing a UV shielding agent and apply it as a buffer layer between the ultra-thin glass and the flexible optoelectronic device through a vacuum lamination process. Use a UV gradient curing process to form a modulus gradient distribution. Finally, at a process temperature of 45-98℃, perform low-temperature welding and sealing on the positive and negative electrode lead-out channels and the peripheral metal weld beads to construct a symmetrical encapsulation structure with double edge barriers.

[0005] Furthermore, in step two, an aperiodic HfO2 / MgF2 multilayer interference film is prepared using a thin film deposition process. Specifically, the thin film deposition process employs an ion-assisted deposition process, in which an argon ion beam generated by an ion source continuously bombards the grown film layer during the deposition process. The momentum transfer effect of high-energy particles is utilized to suppress the formation of columnar crystals, increase the film layer packing density, and seal the water and oxygen permeability micropores. The HfO2 deposition rate is controlled at 0.15-0.25 nm / s, and the MgF2 deposition rate is controlled at 0.3-0.5 nm / s. The ion energy is set to 200-500 eV.

[0006] Specifically, the aperiodic HfO2 / MgF2 multilayer interference film in step two is composed of 10 functional layers of different physical thicknesses stacked alternately, from the surface of the ultrathin glass outwards as follows: (1) Layer 1: HfO2, 15-25 nm; (2) Layer 2: MgF2, 85-100 nm; (3) Layer 3: HfO2, 35-50 nm; (4) Layer 4: MgF2, 110-130 nm; (5) Layer 5: HfO2, 160-200 nm, serving as the core layer for radiation cooling; (6) Layer 6: MgF2, 60-80 nm; (7) Layer 7: HfO2, 55-80 nm; (8) Layer 8: MgF2, 105-125 nm; (9) Layer 9: HfO2, 30-55 nm; (10) Layer 1: HfO2, 30-55 nm; (10) Layer 1: HfO2, 15-25 nm; (11) Layer 2: MgF2, 85-100 nm; (2) Layer 2: HfO2, 85-100 nm; (3) Layer 3: HfO2, 35-50 nm; (4) Layer 4: MgF2, 110-130 nm; (5) Layer 5: HfO2, 160-200 nm, serving as the core layer for radiation cooling; (6) Layer 6: MgF2, 60-80 nm; (7) Layer 7: HfO2, 55-80 nm; (8) Layer 8: MgF2, 105-125 nm; (9) Layer 9: HfO2, 30-55 nm; (10) Layer 1: HfO2, 30-55 nm 10: MgF2, 85-95 nm.

[0007] Furthermore, step three is implemented through the following sub-steps: (3.1) Before or after each metal deposition layer, a physical mask is used to pattern and partition the metal layers, creating electrically insulated positive electrode lead-out areas, negative electrode lead-out areas, and peripheral metal weld beads surrounding the device. During each metal deposition process, the sputtering power density is set to a range of 0.5-2.0 W / cm². 2 And control the ratio of single splash time to pause time to 1:2; (3.2) In a vacuum degree better than 5×10 -4 Within the chamber of Pa, the target material is selected in sequence as the metal seed layer, the anti-diffusion layer, the conductive main layer, and the anti-oxidation welding layer. (3.3) First, a chromium or titanium layer with a thickness of 30-50 nm is deposited on the second surface of the ultrathin glass as a seed layer; (3.4) Subsequently, a nickel or platinum layer with a thickness of 100-200 nm is deposited on the surface of the metal seed layer as an anti-diffusion layer; (3.5) Next, deposit a copper, silver or aluminum layer with a thickness of 200-400 nm on the surface of the anti-diffusion layer as the conductive main layer; (3.6) Finally, deposit a gold or platinum layer with a thickness of 40-80 nm on the surface of the conductive main layer as the anti-oxidation welding layer.

[0008] Specifically, the barrier adhesive dam containing moisture-absorbing functional components in step four has a matrix of any one of modified isobutylene-isoprene rubber, polyisobutylene rubber, or silicone rubber, and is uniformly dispersed with 5-20 wt% inorganic moisture-absorbing nanoparticles inside; the inorganic moisture-absorbing nanoparticles are nano-calcium powder with a particle size between 50-200 nm or inorganic molecular sieve powder with a pore size of 0.3-0.5 nm.

[0009] Specifically, the low-temperature welding process in step five uses indium-based solder, bismuth-tin-based local eutectic solder paste or conductive adhesive with a melting point range of 45-98℃. The welding heating temperature is set to 80-95℃ and the hot pressing pressure is 0.1-0.4MPa to prevent the welding heat from being conducted to the interior of the flexible optoelectronic device and causing thermal degradation.

[0010] Specifically, the liquid polymer resin containing the UV masking agent in step five is obtained by physically mixing liquid polyurethane acrylate resin or epoxy acrylate resin with a UV absorber. The mixing process involves dispersing 0.5-2.0 wt% of the UV masking agent in the resin matrix and stirring it evenly by high-speed centrifugation. The UV absorber is UV-326 or TINUVIN series. The UV gradient curing process utilizes the deep attenuation effect of the UV masking agent on light intensity to form a modulus gradient structure in the resin layer with high crosslinking degree near the ultrathin glass side and low crosslinking degree near the flexible optoelectronic device side.

[0011] Specifically, the symmetrical packaging structure consists of, from top to bottom, a first functionalized ultrathin glass layer, a first modulus gradient buffer layer, a secondary barrier ring and an outer low-temperature metal weld network, a flexible optoelectronic device, a second modulus gradient buffer layer, and a second functionalized ultrathin glass layer.

[0012] Specifically, the flexible optoelectronic device is a flexible silicon solar cell, a flexible perovskite solar cell, or a flexible organic solar cell.

[0013] Furthermore, the flexible organic solar cell and the flexible perovskite solar cell have an average transmittance of less than 5% in the wavelength range below 300nm, so as to achieve ultraviolet shielding protection for the organic active layer and the perovskite layer.

[0014] The beneficial effects of this invention are that it uses ultra-thin glass with high barrier properties as the substrate, combined with patterned metal weld beads and moisture-absorbing barrier adhesive dikes, polymer resin buffer layers, ultra-low temperature welding processes, and symmetrical packaging designs, achieving 10 -5 g / m 2 The extremely low water and oxygen permeability at the per-day level provides excellent environmental stability. The integration of broadband antireflection and passive radiative cooling through a non-periodic interference film effectively reduces device operating temperature, improves photoelectric conversion efficiency, and extends material lifetime. The use of intermittent sputtering technology and a modulus-gradient PUA resin buffer layer effectively absorbs thermal and mechanical stress, reducing the breakage rate of ultra-thin glass during encapsulation and significantly suppressing microcrack formation in flexible silicon cells during bending. Its scientific methodology and highly controllable process provide a high-performance solution for the large-scale industrial encapsulation of flexible perovskite, organic, and flexible silicon solar cells. Attached Figure Description

[0015] Figure 1 This is a schematic cross-sectional view of the packaging device structure of the present invention; Figure 2 This is a schematic diagram of the planar layout of the packaged device of the present invention. Detailed Implementation

[0016] The present invention will be described in further detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0017] To more clearly illustrate the flexible optoelectronic device packaging method based on multifunctional ultrathin glass and the symmetrical packaging structure constructed according to the present invention, the accompanying drawings are provided. Figure 1 and attached Figure 2 The spatial layout, connections and interrelationships between the structural layers are described in detail.

[0018] like Figure 1 The schematic cross-sectional view of the encapsulated device structure shown indicates that the encapsulation structure of the present invention includes, from top to bottom: a first aperiodic interference film 101, a first ultrathin glass layer 102, a first peripheral metal weld bead 103, a first modulus gradient buffer layer 104, a first butyl rubber dam 105, a flexible optoelectronic device 106, a second butyl rubber dam 107, a second modulus gradient buffer layer 108, a second peripheral metal weld bead 109, a second ultrathin glass layer 1010, and a second aperiodic interference film 1011.

[0019] like Figure 2 The schematic diagram of the planar layout shows that the symmetrical packaging structure constructed by the present invention is located in the functionalized ultrathin glass 203. The central gray area is the effective working area of ​​the flexible optoelectronic device 106. Positive electrode lead-out channels 201 and negative electrode lead-out channels 202 are symmetrically distributed on both sides of the gray area. The outermost ring is the outer metal weld bead 204. The butyl rubber cofferdam 205 is located on the inner edge of the metal weld bead, forming a complete annular sealing barrier. The remaining area is filled with a modulus gradient buffer layer 206.

[0020] Each component is integrated within two pieces of functionalized ultrathin glass 203. The central area is the effective working area of ​​the flexible optoelectronic device 106, with symmetrically distributed positive electrode lead-out channels 201 and negative electrode lead-out channels 202 for discrete conductivity on both sides. The outermost ring is surrounded by peripheral metal weld beads 204 (corresponding to the first peripheral metal weld bead 103 and the second peripheral metal weld bead 109 in cross-section). On the inner edge of the peripheral metal weld beads 204, a closed-loop annular butyl rubber weir 205 (corresponding to the first butyl rubber weir 105 and the second butyl rubber weir 107 in cross-section) is provided. The butyl rubber weir 205 is located between the metal weld beads 204 and the central effective working area, forming a continuous, uninterrupted closed secondary moisture interception barrier. The remaining gaps within the aforementioned sealed network are filled with modulus gradient buffer layers 206 (corresponding to the first modulus gradient buffer layer 104 and the second modulus gradient buffer layer 108 in cross-section) to provide mechanical support and stress buffering.

[0021] From a spatial vertical stacking perspective, this fully symmetrical packaging structure, from top to bottom, includes: a first aperiodic interference film 101: deposited on the outermost surface of the top glass layer, used for broadband anti-reflection and atmospheric window radiative cooling; a first ultrathin glass layer 102: serving as the core substrate of the top packaging, providing absolute water and oxygen barrier properties and flexibility; a first peripheral metal weld bead 103: constructed on the inner edge of the first ultrathin glass layer 102, used for edge primary alloying fusion sealing; a first modulus gradient buffer layer 104: sandwiched between the first ultrathin glass layer 102 and the flexible optoelectronic device 106, filling the gaps and achieving a modulus gradient transition; a first butyl rubber dike 105: precisely applied to the inner side of the first peripheral metal weld bead 103, closely adhering to the periphery of the first modulus gradient buffer layer 104, constructing a secondary moisture interception barrier; and a flexible optoelectronic device 106: located on the geometric center vertical axis of the entire packaging structure. The core photoelectric conversion unit under protection includes: a second butyl rubber cofferdam 107, which is symmetrically arranged above and below the first butyl rubber cofferdam 105 and is constructed in the outer periphery below the flexible optoelectronic device 106; a second modulus gradient buffer layer 108, which is symmetrically arranged above and below the first modulus gradient buffer layer 104 and sandwiched between the flexible optoelectronic device 106 and the bottom glass; a second peripheral metal weld bead 109, which is symmetrically arranged above and below the first peripheral metal weld bead 103 and is constructed on the inner surface edge of the second ultrathin glass layer 1010, and is fused and bonded to the first peripheral metal weld bead 103 by low-temperature welding; a second ultrathin glass layer 1010, which serves as the core substrate for the bottom encapsulation and together with the first ultrathin glass layer 102 forms a symmetrical outer shell of "double-sided glass sandwich"; and a second aperiodic interference film 1011, which is deposited on the outermost surface of the bottom glass and together with the first aperiodic interference film 101 maintains the symmetrical stress balance of the device and assists in heat dissipation.

[0022] The aforementioned components work together to achieve primary metal alloy sealing at the edges through peripheral metal welds (first peripheral metal weld 103, second peripheral metal weld 109), and secondary moisture interception through butyl rubber dikes (105, 107) on the inner side. Together with the internal modulus gradient buffer layers (first modulus gradient buffer layer 104, second modulus gradient buffer layer 108), they jointly construct a high-barrier, low-stress, double-dense edge sealing network.

[0023] Comparative Example 1: Flexible Symmetrical Encapsulation Based on PET / Al2O3 / Parylene C This comparative example uses a conventional flexible polymer film as the substrate, and a barrier layer is constructed through atomic layer deposition and chemical vapor deposition (CVD). Its structure from top to bottom is as follows: PET substrate (125 μm) / Al2O3 barrier layer (40 nm) / Parylene C buffer layer (2 μm) / flexible optoelectronic device / Parylene C buffer layer (2 μm) / Al2O3 barrier layer (40 nm) / PET substrate (125 μm).

[0024] The specific process is as follows: First, a 125 μm thick PET film was used for PET substrate pretreatment. It was ultrasonically cleaned sequentially with isopropyl alcohol and deionized water, followed by nitrogen gas to remove adsorbed moisture. Then, an inorganic barrier layer was prepared using atomic layer deposition (ALD). The PET substrate was placed in the ALD reaction chamber. Using trimethylaluminum as the aluminum source and water vapor as the oxygen source, cyclic deposition was performed at a low temperature of 80°C. The growth rate per cycle was approximately 0.1 nm, with a total of 400 cycles, resulting in a dense Al2O3 film with a thickness of approximately 40 nm. Next, an organic buffer layer was prepared using chemical vapor deposition (CVD), depositing Parylene C on the Al2O3 layer surface. Specifically, Parylene C particles were first heated to 150°C for sublimation, and then the dimer was cleaved into monomers at 650°C. The monomers then polymerized on the PET surface at room temperature, forming a transparent film layer with a thickness of approximately 2 μm. Finally, the device was encapsulated and integrated into two functionalized PET encapsulation films prepared above. In a vacuum laminator, optically transparent adhesive was used to clamp the flexible optoelectronic device between the two encapsulation films. Set the bonding pressure to 0.3 MPa and maintain it for 10 minutes to remove air bubbles from the interface.

[0025] Example 1: Symmetrical encapsulation of flexible silicon solar cells based on multifunctional ultrathin glass This embodiment details the complete experimental process of using a 100μm thick flexible crystalline silicon solar cell as the encapsulated device, employing double-sided functionalized and patterned optimized electrodes, and ultra-thin glass with a secondary moisture barrier for fully symmetrical encapsulation.

[0026] (1) Fabrication of functionalized top / bottom UTG substrates (1.1) Substrate pretreatment: Flexible ultrathin glass with a thickness of 100μm was selected and subjected to conventional ultrasonic cleaning with acetone, anhydrous ethanol, and deionized water, as well as oxygen plasma surface activation.

[0027] (1.2) Deposition of aperiodic optical films on the front side: Using ion-assisted electron beam evaporation (IAD), ten aperiodic HfO2 / MgF2 films were deposited on the first surface of the UTG in strict order of physical thickness, specifically: HfO2 (15.2 nm) / MgF2 (98.6 nm) / HfO2 (42.5 nm) / MgF2 (128.4 nm) / HfO2 (195.0 nm) / MgF2 (62.8 nm) / HfO2 (75.3 nm) / MgF2 (118.6 nm) / HfO2 (48.2 nm) / MgF2 (85.5 nm). After deposition, the films were annealed at 250°C for 30 minutes to induce HfO2 microcrystallization. The resulting films were then... Figure 1 The first aperiodic interference film 101 and the second aperiodic interference film 1011 are shown in the figure.

[0028] (1.3) Backside Multilayer Metallization Deposition and Patterning Optimization: DC magnetron sputtering was used on the second surface of the UTG (opposite to the optical film). The UTG was placed on a substrate with a high-precision stainless steel physical mask, which was designed with a 2 mm wide peripheral metal bond bead that closed around the edge of the substrate. This step formed... Figure 2 The planar layout shown indicates that 204 represents the outer metal weld bead (corresponding to the following on the cross-section). Figure 1 The first outer metal weld bead 103 and the second outer metal weld bead 109 were deposited sequentially in a vacuum cycle: Cr (40 nm) / Ni (150 nm) / Cu (350 nm) / Au (60 nm). Each layer was subjected to an intermittent control protocol, and real-time temperature measurement showed that the peak temperature of the UTG surface remained at 55°C, with no thermal cracking occurring.

[0029] (1.4) Secondary moisture barrier setup: Using a dispensing machine, precisely spray a ring of moisture-absorbing butyl adhesive along the inner edge of the outer metal weld bead with a line width of 2 mm (spaced 0.5 mm apart). Figure 2 Butyl rubber cofferdam 205 (corresponding to) Figure 1 The first butyl rubber weir 105 and the second butyl rubber weir 107 are shown in the figure. 10 wt% of nano-calcium powder (average particle size 80 nm) is uniformly dispersed within the butyl rubber. The dispensing strip height is controlled at 35 μm, forming a closed-loop secondary moisture interception weir adjacent to the inner side of the metal weld bead.

[0030] (2) Preparation of the packaged device for vacuum lamination (2.1) Preparation of flexible silicon cell: A single crystal silicon wafer thinned to 90 μm is selected, and a 20 nm SnO2 passivation layer is deposited on the electrode surface as the flexible optoelectronic device 106 to be packaged.

[0031] (2.2) Modulus gradient buffer layer preparation: 1.0 wt% photoinitiator TPO, 0.8 wt% UV-326 UV-blocking agent, 0.5 wt% hindered amine light stabilizer HALS and 0.2 wt% silane coupling agent KH-560 are added to polyurethane acrylate prepolymer.

[0032] (2.3) Lamination Assembly: A 30 μm layer of liquid modulus gradient PUA resin is coated on the metal surface of the bottom UTG (i.e., the second ultrathin glass layer 1010). The flexible silicon cell is then bonded together, ensuring that the positive and negative main grid lines of the cell are aligned and overlapped with the patterned discrete positive and negative electrode lead-out channels (201, 202) on the UTG. A 30 μm layer of liquid polyurethane acrylate resin is also coated on the back of the cell, and a top UTG substrate (i.e., the first ultrathin glass layer 102) with the same electrode pattern and butyl rubber dam is placed on top, and symmetrical alignment is performed. At this time, uncured resin layers are symmetrically formed on the upper and lower sides of the flexible optoelectronic device 106, filling the gaps. Figure 2 The area where component 206 is located.

[0033] (2.4) Gradient curing: using 365 nm single-sided light intensity of 15 mW / cm 2 The UV radiation originates from the top glass side and is irradiated for 60 seconds. Utilizing the layer-by-layer attenuation effect of the UV-blocking agent within the resin, a gradient cross-linked network buffer layer, hard at the top and soft at the bottom, is formed, ultimately curing to form... Figure 1 and Figure 2 The first modulus gradient buffer layer 104, the second modulus gradient buffer layer 108, and the plane-filled modulus gradient buffer layer 206 are shown.

[0034] (3) Low-temperature electrical welding and weld sealing The laminated, fully symmetrical assembly is moved into a local hot press welding machine. A 20 μm thick layer of low-melting-point special indium-based eutectic solder paste is pre-applied to the exposed contact points of the outer metal weld bead 204 and the positive and negative electrode lead-out channels (201, 202). The welding head heating temperature is set to 95°C, the hot press pressure to 0.25 MPa, and the holding time to 15 seconds. The local heat rapidly melts the solder, achieving low-resistance lead-out of the positive and negative electrodes, while simultaneously completing the non-destructive, low-temperature, hermetically tight alloying welding between the first outer metal weld bead 103 and the second outer metal weld bead 109, ultimately resulting in the assembly shown below. Figure 1 The double edge-barrier fully symmetrical package assembly shown.

[0035] (4) Performance test results of the embodiment The packaged parts prepared through the above precision process were tested and the following data were obtained: (1) Water and oxygen barrier performance: The overall water and oxygen permeability of the system was reduced from the original 10 -3 The order of magnitude was successfully reduced to 1.8 × 10⁻⁶. -5 g / m 2 / day. (2) Optical and thermal management: The weighted average transmittance of UTG in the 300-1000 nm band is 93%. Under simulated 1-Sun illumination, the radiation cooling equilibrium operating temperature of the packaged device is 52℃ (reduced by 11℃). (3) Mechanical reliability: After 1500 cycles of bending with a bending radius R=20 mm, there are no visible microcracks in the silicon wafer, and the electrical performance degradation is <5%. (4) Environmental stability: After 1000 hours of damp heat aging test in dual 85 (85℃ / 85%RH), the photoelectric conversion efficiency remains above 95.5% of the initial value; even if the test is extended to 2000 hours, the efficiency can still remain above 90%.

[0036] Example 2: Symmetrical encapsulation of PM6:Y6 organic solar cells based on multifunctional ultrathin glass This embodiment details the complete experimental process of achieving high-performance flexible encapsulation using PM6:Y6 organic solar cells with a wide spectral response as the encapsulated device and employing double-sided functionalized modified UTG (top and bottom encapsulation layers).

[0037] (1) Fabrication of functionalized top and bottom UTG substrates (1.1) Substrate cleaning and activation: UTG with a thickness of 100 μm was selected as the first ultrathin glass layer 102 and the second ultrathin glass layer 1010 for encapsulation. It was cleaned by conventional acetone, anhydrous ethanol, and deionized water ultrasonic cleaning and oxygen plasma surface activation according to standard process to enhance the adhesion of subsequent film layers.

[0038] (1.2) Fabrication of the front optical functional layer: A 10-layer aperiodic HfO2 / MgF2 film system optimized for organic solar cells was deposited on the first surface of two UTG wafers using an ion-assisted electron beam evaporation process, forming the first aperiodic interference film 101 and the second aperiodic interference film 1011. The physical thickness and sequence of the film layers were: HfO2 (22.4 nm) / MgF2 (86.8 nm) / HfO2 (45.2 nm) / MgF2 (115.6 nm) / HfO2 (168.4 nm) / MgF2 (72.1 nm) / HfO2 (58.7 nm) / MgF2 (108.3 nm) / HfO2 (32.5 nm) / MgF2 (91.2 nm). The HfO2 deposition rate was set to 0.2 nm / s, and the MgF2 deposition rate was set to 0.4 nm / s. After deposition, the layers were annealed at 250 °C for 30 minutes.

[0039] (1.3) Backside Multilayer Metallized Electrode Deposition and Patterning Optimization: On the second surface of the UTG, patterned deposition is performed using a high-resolution mask magnetron sputtering process. The electrode pattern completely physically separates the large-area collector area from the edge sealing weld beads, such as... Figure 2 The outer metal weld bead 204 (with cross-sections corresponding to the first outer metal weld bead 103 and the second outer metal weld bead 109) is formed. Parallel positive and negative patterned guide rails are drawn out. The metal layer sequence is: Cr (40nm) / Ni (150 nm) / Cu (300nm) / Au (60nm). Each layer is sputtered intermittently to keep the temperature rise below 50°C.

[0040] (1.4) Secondary moisture interception barrier setup: On the inner wall of the patterned outer metal weld bead, a ring of modified butyl rubber strip containing 15 wt% 4A molecular sieve inorganic micro powder is continuously sprayed using a dispensing machine, thus constructing a secondary moisture interception barrier. Figure 1 and Figure 2 The butyl rubber weir 205 (including the first butyl rubber weir 105 and the second butyl rubber weir 107) is used to intercept and absorb trace amounts of water molecules that penetrate from the side of the rubber layer.

[0041] (2) Preparation of the packaged device for vacuum lamination (2.1) Flexible PM6:Y6 organic solar cell device: A device with a PEDOT:PSS / PM6:Y6 / PNDIT-F3N / Ag structure was fabricated on a flexible transparent electrode substrate, which was used as the core of the flexible optoelectronic device 106. The original positive and negative electrodes of the device were led out to the edge through silver paste and thin copper foil.

[0042] (2.2) Modulus gradient buffer layer preparation: 1.5 wt% UV-326, 0.5 wt% hindered amine light stabilizer and 0.2 wt% silane coupling agent are added to polyurethane acrylate prepolymer.

[0043] (2.3) Vacuum Symmetric Lamination: First, a 30 μm layer of prepared liquid PUA resin is coated onto the patterned metal surface of the bottom UTG (second ultrathin glass layer 1010). The prepared flexible organic device is then attached to it, ensuring that the thin copper foil attached to the device is precisely attached to the positive and negative electrode channel guides patterned on the back of the UTG. Subsequently, another 30 μm layer of liquid PUA resin is coated onto the back surface of the organic device, and the top UTG (first ultrathin glass layer 102) is aligned and covered with its metallized surface facing down. The spatial position is adjusted so that the outer metal welds (including the first outer metal weld 103 and the second outer metal weld 109), the positive and negative electrode lead-out channels, and the first butyl rubber weir 105 and the second butyl rubber weir 107 of the top and bottom UTGs are completely overlapped in the vertical projection direction, forming a structure as shown in the figure. Figure 1 The “double-sided UTG sandwich” symmetrical assembly is shown.

[0044] (2.4) Gradient Curing: A uniform pressure of 0.15 MPa is applied in a vacuum laminator, and 365 nm single-sided ultraviolet light is used to irradiate the top glass side for 60 s. Utilizing the deep attenuation effect of the ultraviolet masking agent inside the resin on the light intensity, the resin undergoes gradient cross-linking curing, thus transforming into... Figure 1 The first modulus gradient buffer layer 104 and the second modulus gradient buffer layer 108 are sandwiched between the upper and lower sides of the flexible organic device (corresponding to...). Figure 2 (Modulus gradient buffer layer 206 in the middle filling region).

[0045] (3) Low-temperature electrical welding seal To protect the active layer of the organic solar cell, this embodiment uses bismuth-tin-based low-melting-point eutectic solder paste for edge sealing. The soldering head process temperature is 90°C, a local pressure of 0.2 MPa is applied, and the soldering time is 10 seconds. The local high heat causes the Au anti-oxidation solder layer on the first peripheral metal weld bead 103 and the second peripheral metal weld bead 109 to eutecticly melt with the low-melting-point solder paste, completing the non-destructive low-temperature hermetically sealed connection between the peripheral annular metal weld beads 204 and at the electrode lead-out channels.

[0046] (4) Performance test results of the example (4.1) Barrier performance: Due to the seamless and sealed space formed by the molecular sieve butyl rubber and the surrounding low-melting-point metal solder, the water and oxygen permeability reaches 2.2×10 -5 g / m 2 / day. (2) Thermal management effect: The equilibrium temperature under 1-Sun illumination is 49℃, which is 13℃ lower than that of the non-integrated functional membrane. (3) Mechanical stability: After 1500 cycles of reciprocating bending test with R=15 mm, the efficiency retention rate is 93%, and there is no delamination phenomenon in the lead-out channel and edge. (4) Long-term stability: After being placed in a humid heat aging environment of 85℃ / 85%RH for 30 days, the energy conversion efficiency retention rate is as high as 93.2%; after continuous aging for 60 days, the efficiency retention rate is still greater than 87%.

[0047] Example 3: Symmetrical encapsulation of flexible perovskite solar cells based on multifunctional ultrathin glass This embodiment details the complete experimental process of achieving high-performance, fully symmetrical flexible encapsulation by using flexible perovskite solar cells as the encapsulated device and modifying UTG with double-sided functionalization.

[0048] (1) Fabrication of functionalized top and bottom UTG substrates (1.1) Substrate cleaning and activation: UTG with a thickness of 100 μm was selected as the first ultrathin glass layer 102 and the second ultrathin glass layer 1010 for encapsulation. It was cleaned by conventional acetone, anhydrous ethanol, and deionized water ultrasonic cleaning and oxygen plasma surface activation according to standard process to enhance the adhesion of subsequent film layers.

[0049] (1.2) Fabrication of the front optical functional layer: A 10-layer aperiodic HfO2 / MgF2 film system optimized for organic solar cells was deposited on the first surface of two UTG wafers using an ion-assisted electron beam evaporation process, forming the first aperiodic interference film 101 and the second aperiodic interference film 1011 on the outer side, respectively. The physical thickness and sequence of the film layers are: HfO2 (20.5 nm) / MgF2 (92.4 nm) / HfO2 (40.8 nm) / MgF2 (120.2 nm) / HfO2 (180.5 nm) / MgF2 (65.6 nm) / HfO2 (60.2 nm) / MgF2 (112.5 nm) / HfO2 (35.6 nm) / MgF2 (88.9 nm). After deposition, the layers were annealed at 250 °C for 30 minutes.

[0050] (1.3) Backside Multilayer Metallized Electrode Deposition: On the second surface of the UTG, patterned deposition is performed using a high-resolution mask magnetron sputtering process to form a multilayer metallized electrode. Figure 2 The diagram shows the back side pattern of the outer metal weld bead 204. The deposited metal layer sequence is: Cr (40 nm) / Ni (150 nm) / Cu (300 nm) / Au (60 nm). Each layer was sputtered intermittently to keep the temperature rise below 50°C.

[0051] (1.4) Secondary moisture interception barrier setting: On the inner wall side of the patterned outer metal weld 204, a ring of modified butyl rubber containing 12 wt% nano molecular sieve powder is continuously sprayed with a dispensing machine to construct a butyl rubber dam 205 surrounding the effective working area, which is used to intercept and absorb trace impurity water molecules that penetrate from the side of the adhesive layer.

[0052] (2) Preparation of the packaged device and vacuum lamination (2.1) Flexible perovskite device: A flexible perovskite solar cell based on a PEN substrate was selected (structure: PEN / ITO / MeO-4PACz / perovskite layer / PC). 61 BM / BCP / Ag), which is used as a flexible optoelectronic device 106 located on the central axis, and the device lead-out electrodes are pretreated with conductive adhesive.

[0053] (2.2) Modulus gradient buffer layer preparation: 1.2 wt% UV-326 and 0.3 wt% silane coupling agent are added to polyurethane acrylate prepolymer.

[0054] (2.3) Vacuum symmetric lamination: A 25μm thick layer of prepared liquid PUA resin is coated on the patterned metal surface of the bottom UTG (second ultrathin glass layer 1010), and the perovskite device (flexible optoelectronic device 106) is aligned and bonded. Then, PUA resin of the same thickness is coated on the top surface of the device, and the top UTG (first ultrathin glass layer 102) is covered. The spatial alignment of the two glass layers is adjusted to ensure that the first peripheral metal weld 103, the second peripheral metal weld 109, and the upper and lower butyl rubber cofferdams (first butyl rubber cofferdam 105, second butyl rubber cofferdam 107) are completely and precisely overlapped in the vertical projection. The layers are then pressed together under vacuum to remove interface bubbles.

[0055] (2.4) Gradient curing: Irradiate the top glass side with 365 nm ultraviolet light for 80 s. Utilizing the light intensity gradient effect of the ultraviolet masking agent, a modulus gradient distribution is formed, characterized by "high cross-linking near the UTG side and low cross-linking near the perovskite side". Finally, it is cured and transformed into... Figure 1 The first modulus gradient buffer layer 104 and the second modulus gradient buffer layer 108 (filled in the plane) Figure 2 The medium modulus gradient buffer layer 206 is used to buffer the stress of the brittle perovskite layer.

[0056] (3) Low-temperature electrical welding seal A special indium bismuth tin low-temperature eutectic solder paste is used for sealing in a localized hot-press soldering machine. The solder head temperature is set to 90°C, a pressure of 0.2 MPa is applied, and held for 12 seconds. Under this process, the solder paste flows and eutectic bonds, allowing the first peripheral metal weld bead 103 and the second peripheral metal weld bead 109 to be tightly welded and cured, completing the hermetic seal. At the same time, it avoids excessive heat conduction to the perovskite active layer, ensuring the sealing reliability of the package at room temperature.

[0057] (4) Performance test results of the example (4.1) Water and oxygen barrier: Thanks to the dual barrier of symmetrical double-layer UTG and molecular sieve butyl rubber, the water and oxygen permeability of the system reaches 1.5×10 -5 g / m 2 / day. (2) Optical and thermal management: Under this packaging structure, the device operating temperature is reduced by about 12℃ compared with the unpackaged sample. (3) Mechanical stability: After 1000 cycles of reciprocating bending test with R=15 mm, the efficiency retention rate is 93%, the perovskite layer has no microcrack propagation, and the photoelectric conversion efficiency retention rate is better than 94%. (4) Long-term stability: After aging for 1000 hours under 85℃ / 85%RH humid heat conditions, the energy conversion efficiency retention rate is as high as 93.4%, proving that this symmetrical UTG packaging scheme has excellent protection effect on perovskite devices.

[0058] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.

[0059] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope.

Claims

1. A method for packaging flexible optoelectronic devices based on multifunctional ultrathin glass, characterized in that, Includes the following steps: Step 1: Select ultra-thin glass with a thickness of 50-210μm as the encapsulation substrate, and perform surface cleaning and surface activation treatment in sequence to enhance surface energy; Step 2: A non-periodic HfO2 / MgF2 multilayer interference film is prepared on the first surface of the ultrathin glass by thin film deposition process, and then annealed to induce microcrystallization of the film and release surface stress. Step 3: On the second surface of the ultrathin glass, multiple layers of metal electrode layers are continuously deposited in a single vacuum cycle using a physical vapor deposition process. During the deposition process, an intermittent deposition protocol is executed to control thermal stress, and the metal layer is patterned using a mask or laser patterning process to separate dedicated conductive channels for the positive and negative electrodes of the device and peripheral metal weld beads. Step 4: On the inner side of the outer metal weld bead, a barrier adhesive containing moisture-absorbing components is set up using a precision dispensing process to serve as a secondary moisture interception barrier. Step 5: Prepare a liquid polymer resin containing a UV shielding agent and apply it as a buffer layer between the ultra-thin glass and the flexible optoelectronic device through a vacuum lamination process. Use a UV gradient curing process to form a modulus gradient distribution. Finally, at a process temperature of 45-98℃, perform low-temperature welding and sealing on the positive and negative electrode lead-out channels and the peripheral metal weld beads to construct a symmetrical encapsulation structure with double edge barriers.

2. The flexible packaging method according to claim 1, characterized in that, In step two, a non-periodic HfO2 / MgF2 multilayer interference film is prepared by thin film deposition. Specifically, the thin film deposition process adopts ion-assisted deposition, in which an argon ion beam generated by an ion source continuously bombards the grown film during the deposition process. The momentum transfer effect of high-energy particles is used to suppress the formation of columnar crystals, increase the film packing density, and block water and oxygen permeability micropores. The HfO2 deposition rate is controlled at 0.15-0.25 nm / s, the MgF2 deposition rate is controlled at 0.3-0.5 nm / s, and the ion energy is set at 200-500 eV.

3. The flexible packaging method according to claim 1, characterized in that, The aperiodic HfO2 / MgF2 multilayer interference film in step two is composed of 10 functional layers of different physical thicknesses stacked alternately, from the surface of the ultrathin glass outwards as follows: (1) Layer 1: HfO2, 15-25 nm; (2) Layer 2: MgF2, 85-100 nm; (3) Layer 3: HfO2, 35-50 nm; (4) Layer 4: MgF2, 110-130 nm; (5) Layer 5: HfO2, 160-200 nm, serving as the radiative cooling core layer; (6) Layer 6: MgF2, 60-80 nm; (7) Layer 7: HfO2, 55-80 nm; (8) Layer 8: MgF2, 105-125 nm; (9) Layer 9: HfO2, 30-55 nm; (10) Layer 1: HfO2, 30-55 nm; (10) Layer 1: HfO2, 15-25 nm; (11) Layer 2: MgF2, 85-100 nm; (2) Layer 2: HfO2, 85-100 nm; (3) Layer 3: HfO2, 35-50 nm; (4) Layer 4: MgF2, 110-130 nm; (5) Layer 5: HfO2, 160-200 nm, serving as the radiative cooling core layer; (6) Layer 6: MgF2, 60-80 nm; (7) Layer 7: HfO2, 55-80 nm; (8) Layer 8: MgF2, 105-125 nm; (9) Layer 9: HfO2, 30-55 nm; (10) Layer 1: HfO2, 30-55 nm 10: MgF2, 85-95 nm.

4. The flexible packaging method according to claim 1, characterized in that, Step three is achieved through the following sub-steps: (3.1) Before or after each metal deposition layer, a physical mask is used to pattern and partition the metal layers, creating electrically insulated positive electrode lead-out areas, negative electrode lead-out areas, and peripheral metal weld beads surrounding the device. During each metal deposition process, the sputtering power density is set to a range of 0.5-2.0 W / cm². 2 And control the ratio of single splash time to pause time to 1:2; (3.2) When the vacuum degree is better than 5×10 -4 Within the chamber of Pa, the target material is selected in sequence as the metal seed layer, the anti-diffusion layer, the conductive main layer, and the anti-oxidation welding layer. (3.3) First, a chromium or titanium layer with a thickness of 30-50 nm is deposited on the second surface of the ultrathin glass as a seed layer; (3.4) Subsequently, a nickel or platinum layer with a thickness of 100-200 nm is deposited on the surface of the metal seed layer as an anti-diffusion layer; (3.5) Next, deposit a copper, silver or aluminum layer with a thickness of 200-400 nm on the surface of the anti-diffusion layer as the conductive main layer; (3.6) Finally, deposit a gold or platinum layer with a thickness of 40-80 nm on the surface of the conductive main layer as the anti-oxidation welding layer.

5. The flexible packaging method according to claim 1, characterized in that, The barrier adhesive dam containing moisture-absorbing functional components in step four has a matrix of any one of modified isobutylene-isoprene rubber, polyisobutylene rubber, or silicone rubber, and is uniformly dispersed with 5-20 wt% inorganic moisture-absorbing nanoparticles inside; the inorganic moisture-absorbing nanoparticles are nano-calcium powder with a particle size between 50-200 nm or inorganic molecular sieve powder with a pore size of 0.3-0.5 nm.

6. The flexible packaging method according to claim 1, characterized in that, The low-temperature welding process in step five uses indium-based solder, bismuth-tin-based local eutectic solder paste, or conductive adhesive with a melting point range of 45-98℃. The welding heating temperature is set to 80-95℃, and the hot pressing pressure is 0.1-0.4MPa to prevent the welding heat from being conducted to the interior of the flexible optoelectronic device and causing thermal degradation.

7. The flexible packaging method according to claim 1, characterized in that, The liquid polymer resin containing the UV masking agent in step five is obtained by physically mixing liquid polyurethane acrylate resin or epoxy acrylate resin with a UV absorber. The mixing process involves dispersing 0.5-2.0 wt% of the UV masking agent in the resin matrix and stirring it evenly by high-speed centrifugation. The UV absorber is UV-326 or TINUVIN series. The UV gradient curing process utilizes the deep attenuation effect of the UV masking agent on light intensity to form a modulus gradient structure in the resin layer with high crosslinking degree near the ultrathin glass side and low crosslinking degree near the flexible optoelectronic device side.

8. The flexible packaging method according to claim 1, characterized in that, The symmetrical packaging structure consists of, from top to bottom, a first functionalized ultrathin glass layer, a first modulus gradient buffer layer, a secondary barrier ring and an outer low-temperature metal weld network, a flexible optoelectronic device, a second modulus gradient buffer layer, and a second functionalized ultrathin glass layer.

9. The flexible packaging method according to claim 1, characterized in that, The flexible optoelectronic device is a flexible silicon solar cell, a flexible perovskite solar cell, or a flexible organic solar cell.

10. The flexible packaging method according to claim 9, characterized in that, The flexible organic solar cell and flexible perovskite solar cell have an average transmittance of less than 5% in the wavelength range below 300nm, so as to achieve ultraviolet shielding protection for the organic active layer and the perovskite layer.

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