Mobile phone display backboard integrated with perovskite solar cell and application thereof

Abstract

The application relates to the field of photoelectric manufacturing technology and discloses a mobile phone display backboard integrated with a perovskite solar cell and application thereof, which comprises the following steps: sputtering a hole transport layer in a preset photovoltaic area of a flexible film substrate, coating and exposing to form a photosensitive liquid-repellent partition wall; spraying a ternary perovskite precursor solution into the partition wall grid, forming a black-phase ternary perovskite light-absorbing layer through vacuumizing and annealing; sequentially evaporating an electron transport layer, a hole barrier layer and a metal electrode and dividing a sub-cell; welding a chip and a patch diode in a non-photovoltaic area, printing a heat-conducting paste and baking the heat-conducting paste into a heat-conducting layer; and sequentially dropping high-refractive-index, medium-refractive-index and low-refractive-index resin liquids to complete stepwise packaging. The application limits the range of the liquid-repellent partition wall, improves crystallinity through vacuum annealing, combines the heat-conducting layer and the diode bypass to relieve heat accumulation and attenuation, coats gradient refractive indexes to reduce interface total reflection, and improves the light extraction efficiency and operation stability of the mobile phone backboard photovoltaic device.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic manufacturing technology, specifically to a mobile phone display backplate integrating perovskite solar cells and its application. Background Technology

[0002] As smart terminals develop towards longer battery life and more multifunctionality, integrating photovoltaic devices into the back panel of mobile phone displays to achieve energy self-sufficiency has become a technological trend. Perovskite solar cells, due to their high light absorption coefficient and flexible fabrication capabilities, have a foundation for application in the field of consumer electronics integration. However, in the actual integration of perovskite solar cells with mobile phone display back panels, existing fabrication processes have revealed many technical bottlenecks.

[0003] Energy level mismatch exists at heterogeneous interfaces, which hinders the extraction of internal charge carriers. In large-area liquid phase preparation, crosstalk between adjacent cell units occurs when the precursor solution is spread on the substrate, forming leakage current channels. Conventional film deposition processes have difficulty controlling solvent evaporation rate and nucleation kinetics, resulting in insufficient crystallinity of perovskite films and an increase in internal grain boundary defects, which restricts the basic photoelectric conversion performance of the device.

[0004] The enclosed space inside a mobile phone places stringent requirements on the operational stability of photovoltaic devices. Components such as the processor generate a large amount of heat during operation. Traditional backplane structures lack a lateral heat diffusion mechanism, and the accumulated heat is conducted to the photovoltaic area, causing thermal degradation of organic cations in the perovskite film. When a local battery cell is shaded by external components or the usage environment, the conventional series circuit lacks a bypass shunt design, and the reverse bias voltage causes a hot spot effect, resulting in irreversible physical damage to the film.

[0005] In terms of optical structure design, existing photovoltaic encapsulation layers mostly use a single refractive index medium. There is a sudden change in refractive index between the encapsulation material and the external air and internal electrodes. The sudden change in optical interface aggravates the total internal reflection of light at the interface, reduces the optical path, and limits the effective coupling of light flux to the internal absorption layer, resulting in limited overall light extraction efficiency of the device. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a mobile phone display backplate integrating perovskite solar cells and its application, solving the problems of heterogeneous interface energy level mismatch, poor crystal quality of perovskite thin film, heat accumulation of heat-generating chips leading to photovoltaic module degradation, and total internal reflection of optical interfaces resulting in limited light extraction efficiency when integrating photovoltaic devices in existing mobile phone backplates.

[0007] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a mobile phone display backplate integrating perovskite solar cells, wherein the fabrication process of the mobile phone display backplate includes the following steps: Polydimethylsiloxane and curing agent are spin-coated onto a carrier plate and annealed to form a temporary adhesive layer. The flexible film substrate is then bonded together and interfacial bubbles are removed. The flexible film substrate is cleaned and treated with ultraviolet ozone. A hole transport layer is sputtered into a preset photovoltaic area. A photosensitive hydrophobic barrier material is coated onto the hole transport layer, and then exposed and cured by development to form a photosensitive hydrophobic barrier. The ternary perovskite precursor solution was sprayed into the grid defined by the photosensitive hydrophobic isolation wall, and then vacuumed and annealed to form a black phase ternary perovskite light-absorbing layer. An electron transport layer, a hole blocking layer, and a metal electrode are sequentially deposited on a black ternary perovskite light-absorbing layer, and multiple series-connected sub-cell units are divided using a laser scribing process. Metal lines are sputtered in non-photovoltaic areas, and low-temperature solder paste is used to complete the surface mounting of display driver chips, photovoltaic power management chips and micro-surface diodes; patterned in-plane thermal conductive paste is printed onto the back of the heat-generating chip and the non-transparent area and baked into a thermal conductive layer. High-refractive-index resin liquid, medium-refractive-index resin liquid, and low-refractive-index resin liquid are sequentially drop-coated and cured on the outer surface of the metal electrode and the preset photovoltaic area to complete the stepped coating and obtain the mobile phone display back panel of the integrated perovskite solar cell.

[0008] By adopting the above technical solution, ultraviolet ozone treatment of the flexible thin film substrate surface initiates a photochemical oxidation reaction, decomposes hydrocarbon pollutants, and introduces hydroxyl and carboxyl functional groups on the surface of the flexible thin film substrate to increase the surface free energy. Subsequently, inorganic NiOx is sputtered and deposited as a hole transport layer, providing a valence band energy level that matches the perovskite layer, forming an ohmic contact to promote hole extraction. To achieve fluid confinement, a patterned photosensitive hydrophobic isolation wall is formed using photolithography.

[0009] The hydrophobic surface forms a low surface energy physical barrier. When the sprayed droplets come into contact with the hydrophobic surface, a large contact angle repulsion effect is formed at the three-phase contact line, which confines the precursor solution within a specific grid and suppresses crosstalk between adjacent battery cell solutions and the generation of leakage current channels. The precursor liquid film undergoes phase change crystallization under vacuum and annealing. Lead halide in the precursor undergoes coordination reaction with organic cations and alkali metal cations. The vacuum operation accelerates the removal of mixed solvent molecules, and the solution quickly crosses the solubility curve to reach a supersaturated state, forming an intermediate phase nucleus.

[0010] Annealing heat treatment provides activation energy, causing the meso phase to undergo a solid-state transformation into a photovoltaic-active black phase structure, improving the crystallinity of the perovskite film and reducing grain boundary defects. A stepped band structure is constructed by sequentially depositing C60 and BCP. C60 extracts photogenerated electrons, while BCP blocks reverse hole injection. A parallel bypass is formed by integrating micro-surface diodes. When a sub-cell cell is physically blocked and generates a hot spot effect, the reverse bias voltage applied by the series circuit activates the diode to conduct in the forward direction, guiding the current to bypass the blocked cell and preventing reverse breakdown from damaging the photovoltaic film.

[0011] After baking and curing, the patterned in-plane thermally conductive paste forms a network with in-plane thermal conductivity, which conducts and diffuses the local heat flow of the heating chip laterally, alleviating the degradation of organic cations in perovskite materials caused by thermal stress concentration. After curing, resin liquids with different refractive indices are drop-coated on the outside, forming a gradient refractive index medium according to Snell's law, reducing the total internal reflection phenomenon at the interface caused by abrupt changes in refractive index, and increasing the optical path of oblique incident light and the luminous flux coupled into the photovoltaic region.

[0012] Preferably, the parameters for preparing the temporary adhesive layer and hole transport layer are as follows: polydimethylsiloxane and a curing agent are mixed uniformly, spin-coated onto a carrier plate at a speed of 1500 to 2500 r / min, and annealed at 90 to 110°C for 50 to 70 minutes to form the temporary adhesive layer; the flexible film substrate is subjected to ultraviolet ozone treatment for 8 to 12 minutes; and the process is carried out under a vacuum degree lower than 9 × 10⁻⁶. -4 Hole transport layers were fabricated by sputtering NiOx material at a power of 50 to 60 W under Pa conditions.

[0013] By adopting the above technical solution, the set rotation speed and annealing temperature jointly regulate the polymer crosslinking density, which helps to balance the substrate flatness and the interfacial bonding force required for subsequent peeling. Limiting the magnetron sputtering power can reduce substrate lattice damage caused by excessive kinetic energy of high-energy particles, and is also conducive to improving the growth density of NiOx grains and reducing pinhole density.

[0014] Preferably, the parameters for spraying the ternary perovskite precursor solution are: the gap between the spray nozzle and the flexible film substrate is set to 0.8 to 1.2 cm, the solution injection speed is 0.20 to 0.30 mm / min, and the atomization pressure is 0.12 to 0.18 MPa.

[0015] By adopting the above technical solution, the set nozzle gap, injection speed and atomization pressure jointly intervene in the droplet SOT average diameter. Droplets of appropriate size have matching kinetic energy when they reach the isolation wall grid, which facilitates rapid spread to form a continuous liquid film and suppresses local film thickness abrupt changes or coffee ring effect caused by excessively large droplets.

[0016] Preferably, the vacuuming parameters are: within 8 to 12 seconds after spraying, the vacuum level is reduced to below 8 to 12 Pa and maintained for 1.5 to 2.5 minutes.

[0017] By adopting the above technical solution, the limited negative pressure time window causes the solvent gas partial pressure on the wet film surface to drop rapidly, driving polar high-boiling-point solvent molecules to escape from the system in the early stage of film formation. This pumping operation regulates the crystal nucleus generation rate, induces heterogeneous nucleation to transform into homogeneous nucleation, and increases the nucleation density to form a small-sized, fine-grained, dense precursor film.

[0018] Preferably, the annealing parameters for forming the black phase ternary perovskite light-absorbing layer are: annealing temperature controlled at 145 to 155°C, and annealing time at 8 to 12 minutes.

[0019] By adopting the above technical solution, the set temperature window provides thermodynamic driving force for the crystal phase reconstruction of the intermediate complex of the precursor, promotes the transformation of the black phase structure, limits the annealing time to prevent the long-term high temperature exposure from causing the release of volatile cations such as formamidinium or methylammonium in the system, and helps to maintain the stability of the stoichiometry of the perovskite lattice structure.

[0020] Preferably, the parameters for the vapor-deposited electron transport layer and hole blocking layer are: at a vacuum level below 9×10⁻⁶. -4 Under Pa conditions, a C60 material with a thickness of 200 to 300 Å was deposited as an electron transport layer at a rate of 0.08 to 0.12 Å / s, followed by a BCP material with a thickness of 50 to 80 Å as a hole blocking layer at a rate of 0.05 to 0.10 Å / s.

[0021] By adopting the above technical solution, the evaporation rate of C60 molecules is controlled so that they have time to diffuse on the surface after contacting the bottom surface, passivating the uncoordinated lead ion defects on the perovskite surface, forming a dense covering layer, controlling the thickness of the BCP material layer within a limited range, maintaining the smooth progress of the electron tunneling effect, and at the same time using the deep valence band characteristics of BCP to block the migration of holes across the interface.

[0022] Preferably, the parameters for the vapor-deposited metal electrode are: a copper electrode with a thickness of 500 to 700 Å is vapor-deposited at a rate of 1.0 to 2.0 Å / s.

[0023] By adopting the above technical solution, the set evaporation rate promotes the continuous island-like growth of copper atoms on the surface of the bottom organic barrier layer and eventually merges them into a continuous film layer, providing planar conductivity to reduce series resistance; at the same time, it limits the latent heat release rate of film formation and reduces the risk of thermal penetration effect destroying the molecular arrangement morphology of the lower organic electron transport layer.

[0024] Preferably, the low-temperature solder paste is tin-bismuth low-temperature solder paste, and the environment for completing the surface mount soldering using the low-temperature solder paste is a heating table at 145 to 155°C.

[0025] By adopting the above technical solution, the eutectic melting point of the tin-bismuth solid solution is within the set heating range. Since the temperature range is close to the crystallization annealing temperature of the perovskite light-absorbing layer, when surface mounting electronic components, the additional thermal stress introduced to the photovoltaic thin film already constructed in the adjacent area can be reduced, and the thermal degradation of the crystal phase can be suppressed.

[0026] Preferably, the parameters for forming the heat-conducting layer are: baking and drying at 120 to 140°C.

[0027] By adopting the above technical solution, the set baking temperature drives the carrier solvent in the thermally conductive paste system to evaporate and promotes the cross-linking and entanglement of macromolecular chain segments, fixing the thermally conductive filler in the polymer matrix network. The operating temperature is within the thermal stability threshold of each optoelectronic functional material, which helps to maintain the overall performance of the device.

[0028] Secondly, the present invention also provides the application of a mobile phone display backplate integrating perovskite solar cells in the fabrication of smartphone electronic terminals.

[0029] By adopting the above technical solution, the mobile phone display back panel integrating perovskite solar cells is configured in the smartphone terminal. The flexible thin film substrate is mechanically compliant and fits the device shell structure. The photovoltaic area collects ambient scattered light or direct light and converts it into electrical energy input to the power management chip. The heat conduction network guides the heat generated by the processor inside the device, improving the energy self-sufficiency of the terminal device and extending its operational stability.

[0030] This invention provides a mobile phone display backplate integrating perovskite solar cells and its application. It has the following beneficial effects: 1. This invention constructs a photosensitive hydrophobic isolation wall on the surface of the hole transport layer and combines vacuuming and annealing temperature window treatment of the ternary perovskite precursor solution. The low surface energy physical barrier effect of the photosensitive hydrophobic isolation wall confines the precursor solution within a specific grid, suppressing solution crosstalk between adjacent cell units. The vacuuming operation accelerates solvent evaporation and induces homogeneous nucleation of the system. Combined with annealing treatment, it promotes the solid-phase transformation of the perovskite mesophase to the photovoltaic-active black phase structure. The fluid confinement of the isolation wall and the vacuuming crystallization annealing process work together to reduce grain boundary defects inside the film and improve the crystallinity and basic photoelectric conversion performance of the black phase ternary perovskite light-absorbing layer.

[0031] 2. This invention utilizes patterned in-plane thermally conductive paste printing to construct a thermally conductive layer, and integrates micro-surface-mount diodes on metal circuits to form a parallel bypass network. The thermally conductive layer laterally conducts and diffuses the local heat flow generated by the mobile phone's heat-generating chip within the plane, alleviating the degradation of the organic cation structure in the perovskite material caused by thermal stress concentration. When a local photovoltaic cell is physically blocked, the reverse bias voltage generated by the series circuit activates the diode to conduct in the forward direction, guiding the current around the obstructed area. The parallel bypass network formed by the thermally conductive layer and the micro-surface-mount diodes works together to slow down the heat accumulation and decay of the photovoltaic device in the sealed environment of the equipment, while preventing the hot spot effect from damaging the thin film and maintaining the stability of the device operation.

[0032] 3. This invention forms a stepped coating of a multi-stage optical encapsulation composition by sequentially drop-coating and curing high-refractive-index resin liquid, medium-refractive-index resin liquid, and low-refractive-index resin liquid on the outer surface of a preset photovoltaic area. The decreasing refractive index arrangement from the inside to the outside reduces the total internal reflection phenomenon caused by the sudden change in refractive index at the interface of different media, increases the optical path of external incident light obliquely entering the internal structure, and increases the proportion of light flux coupled to the black phase ternary perovskite light-absorbing layer. The stepped resin liquid coating provides physical protection of the encapsulation boundary while improving the overall light extraction and light utilization efficiency of the mobile phone display back panel. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the interface capacitance density as a function of bias voltage according to the present invention. Figure 2 This is a schematic diagram of the steady-state leakage current versus time curve of the present invention; Figure 3 This is a schematic diagram of the cumulative heat capacity versus cumulative thermal resistance curve of the present invention; Figure 4 This is a schematic diagram of the shear test force variation curve with the cutter head displacement according to the present invention; Figure 5 This is a schematic diagram of the average integral absorptivity as a function of the incident angle according to the present invention. Figure 6 This is a schematic diagram of the output power under low light conditions as a function of bias voltage according to the present invention; Figure 7 This is a schematic diagram of the power retention rate and hot spot temperature changing over time according to the present invention. Detailed Implementation

[0034] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] The main raw materials and reagents used in the following examples and comparative examples have the following sources and specifications. Reagents not specifically mentioned are all commercially available analytical grade or higher grade products.

[0036] Boron nitride, CAS No. 10043-11-5, is in the form of hexagonal nanosheets with a lateral size ranging from 1.0 to 5.0 μm and a thickness ranging from 5 to 20 nm, with a purity ≥99.9%.

[0037] The polyamic acid solution is a homopolymer precursor solution formed by the ring-opening condensation reaction of pyromellitic dianhydride and 4,4'-diaminodiphenyl ether in a polar aprotic solvent. The polyamic acid has a weight-average molecular weight (Mw) of 80,000 to 120,000 g / mol and a solid content of 12 wt% to 15 wt%.

[0038] Perfluoropolyether glycol is a linear polymer whose main chain is composed of carbon-oxygen-carbon in an alternating pattern of -(CF2O)- and -(CF2CF2O)-, and is capped at both ends by linear primary hydroxyl groups (-CH2OH). Its number average molecular weight Mn is 1500 to 2000 g / mol, and the terminal hydroxyl functionality is 2.

[0039] Aliphatic polyurethane diacrylate is a linear oligomer whose main chain is formed by the condensation polymerization of polycarbonate diol and aliphatic diisocyanate and is capped with hydroxyethyl acrylate. Its number average molecular weight Mn is 1500 to 2500 g / mol and its kinetic viscosity at room temperature is 50000 to 70000 cP.

[0040] Rutile titanium dioxide, CAS number 1317-80-2, is in the form of nanocrystals with an average particle size of 10 to 20 nm. Its surface is hydrophobically modified and has a refractive index range of 2.6 to 2.7.

[0041] Silica, CAS No. 7631-86-9, is in the form of hollow microspheres with an outer diameter of 50 to 70 nm, a shell thickness of 5 to 15 nm, an internal cavity filled with air, and a surface that has undergone hydrophobic modification treatment. The overall equivalent refractive index ranges from 1.15 to 1.25.

[0042] The tin-bismuth low-temperature solder paste uses commercially available electronic-grade lead-free solder paste. It is a paste-like mixture formed by mixing eutectic alloy micro powder consisting of 42% tin and 58% bismuth by mass with rosin-based flux. The solidus and liquidus temperatures of the alloy are both 138°C.

[0043] In this invention, the units of measurement for all materials and solvents are uniformly referred to as parts by weight.

[0044] Preparation Example 1: This preparation example provides a method for preparing a patterned in-plane thermally conductive paste, including the following steps: Boron nitride was added to a polyamic acid solution, and the volume percentage of boron nitride in the solids was set to 15%. The mixture was stirred evenly to obtain a high-viscosity paste. The high-viscosity paste was sheared and mixed for 2 hours using a three-roll mill at a speed of 100 r / min, so that the boron nitride was oriented in a planar direction along the shear direction in the resin matrix. The paste after grinding was collected, and then an appropriate amount of N-methylpyrrolidone was added as a diluent. The kinetic viscosity of the mixed slurry was adjusted to 10000 cP to obtain a patterned in-plane thermally conductive slurry, hereinafter referred to as patterned in-plane thermally conductive slurry A.

[0045] Preparation Example 2: This preparation example provides a method for preparing a patterned in-plane thermally conductive paste, including the following steps: Boron nitride was added to a polyamic acid solution, and the volume percentage of boron nitride in the solids was set to 22%. After mixing evenly, a high-viscosity paste was obtained. The high-viscosity paste was sheared and mixed for 3 hours using a three-roll mill at a speed of 200 r / min, so that the boron nitride was oriented in a planar direction along the shear direction in the resin matrix. The ground paste was collected, and then an appropriate amount of N-methylpyrrolidone was added as a diluent. The kinetic viscosity of the mixed slurry was adjusted to 12500 cP to obtain a patterned in-plane thermally conductive slurry, hereinafter referred to as patterned in-plane thermally conductive slurry B.

[0046] Preparation Example 3: This preparation example provides a method for preparing a patterned in-plane thermally conductive paste, including the following steps: Boron nitride was added to a polyamic acid solution, and the volume percentage of boron nitride in the solids was set to 30%. After mixing evenly, a high-viscosity paste was obtained. The high-viscosity paste was sheared and mixed for 4 hours using a three-roll mill at a speed of 300 r / min, so that the boron nitride was oriented in a planar direction along the shear direction in the resin matrix. The ground paste was collected, and then an appropriate amount of N-methylpyrrolidone was added as a diluent. The kinetic viscosity of the mixed slurry was adjusted to 15000 cP to obtain a patterned in-plane thermally conductive slurry, hereinafter referred to as patterned in-plane thermally conductive slurry C.

[0047] Preparation Example 4: This preparation example provides a method for preparing a photosensitive hydrophobic barrier material, including the following steps: In a four-necked flask equipped with a mechanical stirrer and a condenser, 40 parts by weight of perfluoropolyether glycol, 12 parts by weight of isophorone diisocyanate, and 0.005 parts by weight of dibutyltin dilaurate were added. The mixture was reacted at 60°C for 2 hours under nitrogen protection to obtain a polyurethane prepolymer. The reaction system was then cooled to 40°C, and the nitrogen flow was stopped and replaced with dry air. Next, 8 parts by weight of hydroxyethyl methacrylate and 0.08 parts by weight of hydroquinone were added dropwise, and the reaction was continued for 3 hours until the infrared absorption peak of the isocyanate group in the reaction system disappeared. After the reaction product was cooled, 2 parts by weight of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide was mixed in as a photoinitiator and stirred evenly to obtain a photosensitive liquid-repellent barrier material, hereinafter referred to as photosensitive liquid-repellent barrier material A.

[0048] Preparation Example 5: This preparation example provides a method for preparing a photosensitive hydrophobic barrier material, including the following steps: In a four-necked flask equipped with a mechanical stirrer and a condenser, 50 parts by weight of perfluoropolyether glycol, 15 parts by weight of isophorone diisocyanate, and 0.007 parts by weight of dibutyltin dilaurate were added. The mixture was reacted at 68°C for 3 hours under nitrogen protection to obtain a polyurethane prepolymer. The reaction system was then cooled to 45°C, and the nitrogen gas was stopped and replaced with dry air. Then, 10 parts by weight of hydroxyethyl methacrylate and 0.10 parts by weight of hydroquinone were added dropwise, and the reaction was continued for 4 hours until the infrared absorption peak of the isocyanate group in the reaction system disappeared. After the reaction product was cooled, 3 parts by weight of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide was mixed in as a photoinitiator and stirred evenly to obtain a photosensitive liquid-repellent barrier material, hereinafter referred to as photosensitive liquid-repellent barrier material B.

[0049] Preparation Example 6: This preparation example provides a method for preparing a photosensitive hydrophobic barrier material, including the following steps: In a four-necked flask equipped with a mechanical stirrer and a condenser, 60 parts by weight of perfluoropolyether glycol, 18 parts by weight of isophorone diisocyanate, and 0.010 parts by weight of dibutyltin dilaurate were added. The mixture was reacted at 75°C for 4 hours under nitrogen protection to obtain a polyurethane prepolymer. The reaction system was then cooled to 50°C, and the nitrogen flow was stopped and replaced with dry air. Then, 12 parts by weight of hydroxyethyl methacrylate and 0.12 parts by weight of hydroquinone were added dropwise, and the reaction was continued for 5 hours until the infrared absorption peak of the isocyanate group in the reaction system disappeared. After the reaction product was cooled, 5 parts by weight of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide was mixed in as a photoinitiator and stirred evenly to obtain a photosensitive liquid-repellent barrier material, hereinafter referred to as photosensitive liquid-repellent barrier material C.

[0050] Preparation Example 7: This preparation example provides a method for preparing a multi-level optical packaging composition, including the following steps: 60 parts by weight of aliphatic polyurethane diacrylate and 40 parts by weight of isobornyl acrylate were mixed evenly to form a matrix resin. 2 parts by weight of 2-hydroxy-2-methyl-1-phenyl-1-propanone were added as a photoinitiator. The matrix resin was then divided into three equal parts by weight: a first part, a second part, and a third part. 30% by weight of surface-hydrophobic modified rutile titanium dioxide relative to the first part of the matrix resin was ultrasonically dispersed into the first part to obtain a high-refractive-index resin liquid. Then, 10% by weight of surface-hydrophobic modified rutile titanium dioxide relative to the second part of the matrix resin was ultrasonically dispersed into the second part to obtain a medium-refractive-index resin liquid. Finally, 6% by weight of silica relative to the third part of the matrix resin was ultrasonically dispersed into the third part to obtain a low-refractive-index resin liquid. This yielded a multi-stage optical encapsulation composition, hereinafter referred to as Multi-stage Optical Encapsulation Composition A.

[0051] Preparation Example 8: This preparation example provides a method for preparing a multi-level optical packaging composition, including the following steps: 65 parts by weight of aliphatic polyurethane diacrylate and 35 parts by weight of isobornyl acrylate were mixed evenly to form a matrix resin. 2.5 parts by weight of 2-hydroxy-2-methyl-1-phenyl-1-propanone were added as a photoinitiator. The matrix resin was then divided into three equal parts by weight: a first part, a second part, and a third part. 35% by weight of surface-hydrophobic modified rutile titanium dioxide was ultrasonically dispersed in the first part of the matrix resin to obtain a high-refractive-index resin solution. Then, 15% by weight of surface-hydrophobic modified rutile titanium dioxide was ultrasonically dispersed in the second part of the matrix resin to obtain a medium-refractive-index resin solution. Finally, 8% by weight of silica was ultrasonically dispersed in the third part of the matrix resin to obtain a low-refractive-index resin solution. This yielded a multi-stage optical encapsulation composition, hereinafter referred to as Multi-stage Optical Encapsulation Composition B.

[0052] Preparation Example 9: This preparation example provides a method for preparing a multi-level optical packaging composition, including the following steps: 70 parts by weight of aliphatic polyurethane diacrylate and 30 parts by weight of isobornyl acrylate were mixed evenly to form a matrix resin. 3 parts by weight of 2-hydroxy-2-methyl-1-phenyl-1-propanone were added as a photoinitiator. The matrix resin was then divided into three equal parts by weight: a first part, a second part, and a third part. 40% by weight of surface-hydrophobic modified rutile titanium dioxide relative to the first part of the matrix resin was ultrasonically dispersed into the first part to obtain a high-refractive-index resin solution. Then, 20% by weight of surface-hydrophobic modified rutile titanium dioxide relative to the second part of the matrix resin was ultrasonically dispersed into the second part to obtain a medium-refractive-index resin solution. Finally, 10% by weight of silica relative to the third part of the matrix resin was ultrasonically dispersed into the third part to obtain a low-refractive-index resin solution. This yielded a multi-stage optical encapsulation composition, hereinafter referred to as multi-stage optical encapsulation composition C.

[0053] Preparation Example 10: This preparation example provides a method for preparing a ternary perovskite precursor solution, including the following steps: Cesium iodide, formamidinium hydroiodate, methylammonium hydroiodate, and lead iodide solid powder in a molar ratio of 0.05:0.10:1.10:1.30 were added to a mixed solvent composed of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone in a volume ratio of 8:2:1. The molar concentration of lead ions in the mixed solution was controlled to be 0.8 mol / L. The mixture was continuously magnetically stirred at 40°C for 1 hour. After the mixed solution cooled, it was filtered through a 0.22 μm polytetrafluoroethylene filter membrane to obtain a ternary perovskite precursor solution, hereinafter referred to as ternary perovskite precursor solution A.

[0054] Preparation Example 11: This preparation example provides a method for preparing a ternary perovskite precursor solution, including the following steps: Cesium iodide, formamidinium hydroiodate, methylammonium hydroiodate, and lead iodide solid powder in a molar ratio of 0.07:0.15:1.25:1.52 were added to a mixed solvent composed of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone in a volume ratio of 9:2.5:1.5. The molar concentration of lead ions in the mixed solution was controlled at 1.1 mol / L, and the mixture was continuously magnetically stirred at 50°C for 1.5 hours. After the mixed solution cooled, it was filtered through a 0.33 μm polytetrafluoroethylene filter membrane to obtain a ternary perovskite precursor solution, hereinafter referred to as ternary perovskite precursor solution B.

[0055] Preparation Example 12: This preparation example provides a method for preparing a ternary perovskite precursor solution, including the following steps: Cesium iodide, formamidinium hydroiodate, methylammonium hydroiodate, and lead iodide solid powder in a molar ratio of 0.10:0.20:1.40:1.75 were added to a mixed solvent composed of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone in a volume ratio of 10:3:2. The molar concentration of lead ions in the mixed solution was controlled at 1.5 mol / L, and the mixture was continuously magnetically stirred at 60°C for 2 hours. After the mixed solution cooled, it was filtered through a 0.45 μm polytetrafluoroethylene filter membrane to obtain a ternary perovskite precursor solution, hereinafter referred to as ternary perovskite precursor solution C.

[0056] Example 1: This embodiment provides a method for fabricating a mobile phone display backplane integrating a perovskite solar cell, including the following steps: Polydimethylsiloxane and curing agent were mixed uniformly at a mass ratio of 10:1 and spin-coated onto the surface of a glass substrate at 1500 r / min. A temporary adhesive layer was prepared by annealing at 90°C for 70 minutes. A flexible polyimide film was then bonded to the temporary adhesive layer, and interfacial bubbles were removed under vacuum. Subsequently, the surface of the flexible polyimide film was cleaned sequentially with deionized water and isopropanol, followed by UV ozone treatment for 8 minutes. The treated flexible polyimide film was then placed in a magnetron sputtering apparatus and subjected to a vacuum degree below 9 × 10⁻⁶. -4 Under Pa conditions, a NiOx hole transport layer was sputtered in a preset photovoltaic region of a polyimide flexible film at a power of 50W.

[0057] A photosensitive hydrophobic barrier material A is uniformly coated on the surface of the NiOx hole transport layer. The photosensitive hydrophobic barrier material A is exposed to ultraviolet light and developed using a preset grid mask. After curing, a photosensitive hydrophobic barrier is formed distributed on the surface of the NiOx hole transport layer.

[0058] Ternary perovskite precursor solution A was injected into the spraying equipment. The gap between the nozzle and the polyimide flexible film was set to 0.8 cm, the solution injection speed to 0.20 mm / min, and the atomization pressure to 0.12 MPa. Ternary perovskite precursor solution A was sprayed onto the grid defined by the photosensitive hydrophobic isolation wall. Immediately after spraying, the wetted polyimide flexible film was transferred to the vacuum chamber. The vacuum was reduced to below 8 Pa within 8 seconds and maintained for 1.5 minutes. Subsequently, it was annealed at 145°C for 12 minutes to form a black phase ternary perovskite light-absorbing layer.

[0059] A flexible polyimide film with a black-phase ternary perovskite light-absorbing layer was placed in a vacuum evaporation chamber at a vacuum level below 9 × 10⁻⁶. -4Under Pa conditions, a 200 Å thick C60 electron transport layer was deposited sequentially at a rate of 0.08 Å / s, followed by a 50 Å thick BCP hole blocking layer at a rate of 0.05 Å / s. Then, a 500 Å thick copper electrode was deposited at a rate of 1.0 Å / s. The photovoltaic region was then divided into multiple series-connected sub-cell units using a laser scribing process, thus completing the construction of the perovskite solar cell.

[0060] Copper metal lines were sputtered onto the non-photovoltaic areas of the polyimide flexible film, and diode mounting pads were reserved. Then, the display driver chip, photovoltaic power management chip, and micro-surface diode were surface-mounted and soldered using tin-bismuth low-temperature solder paste on a 145°C heating stage to construct a parallel bypass network. Next, patterned in-plane thermal conductive paste A was printed onto the back of the heat-generating chip and the non-transparent area using screen printing technology, and then baked and dried at 120°C to form a thermally conductive layer with a heat dissipation network pattern.

[0061] The high-refractive-index resin liquid, medium-refractive-index resin liquid, and low-refractive-index resin liquid contained in the multi-stage optical encapsulation composition A are sequentially drop-coated and cured to complete the step-by-step coating of the encapsulation resin layer, and finally obtain the mobile phone display back panel integrating perovskite solar cells.

[0062] Example 2: This embodiment provides a method for fabricating a mobile phone display backplane integrating a perovskite solar cell, including the following steps: Polydimethylsiloxane and curing agent were mixed uniformly at a mass ratio of 10:1 and spin-coated onto the surface of a glass substrate at 2000 r / min. A temporary adhesive layer was then formed by annealing at 100℃ for 60 minutes. A flexible polyimide film was then bonded to the temporary adhesive layer, and interfacial bubbles were removed under vacuum. Subsequently, the surface of the flexible polyimide film was cleaned sequentially with deionized water and isopropanol, followed by UV ozone treatment for 10 minutes. The treated flexible polyimide film was then placed in a magnetron sputtering apparatus and subjected to a vacuum degree below 9 × 10⁻⁶. -4 Under Pa conditions, a NiOx hole transport layer was sputtered in a preset photovoltaic region of a polyimide flexible film at a power of 55W.

[0063] A photosensitive hydrophobic barrier material B is uniformly coated on the surface of the NiOx hole transport layer. The photosensitive hydrophobic barrier material B is exposed to ultraviolet light and developed using a preset grid mask. After curing, a photosensitive hydrophobic barrier is formed distributed on the surface of the NiOx hole transport layer.

[0064] Ternary perovskite precursor solution B was injected into the spraying equipment. The gap between the nozzle and the polyimide flexible film was set to 1.0 cm, the solution injection speed to 0.25 mm / min, and the atomization pressure to 0.15 MPa. The ternary perovskite precursor solution B was sprayed onto the grid defined by the photosensitive hydrophobic isolation wall. Immediately after spraying, the wetted polyimide flexible film was transferred to the vacuum chamber. The vacuum was reduced to below 10 Pa within 10 seconds and maintained for 2 minutes. Subsequently, it was annealed at 150°C for 10 minutes to form a black phase ternary perovskite light-absorbing layer.

[0065] A flexible polyimide film with a black-phase ternary perovskite light-absorbing layer was placed in a vacuum evaporation chamber at a vacuum level below 9 × 10⁻⁶. -4 Under Pa conditions, a 250 Å thick C60 electron transport layer was deposited sequentially at a rate of 0.10 Å / s, followed by a 65 Å thick BCP hole blocking layer at a rate of 0.08 Å / s. Then, a 600 Å thick copper electrode was deposited at a rate of 1.5 Å / s. The photovoltaic region was then divided into multiple series-connected sub-cell units using a laser scribing process, thus completing the construction of the perovskite solar cell.

[0066] Copper metal lines were sputtered onto the non-photovoltaic areas of the polyimide flexible film, and diode mounting pads were reserved. Then, the display driver chip, photovoltaic power management chip, and micro-surface diode were surface-mounted and soldered using tin-bismuth low-temperature solder paste on a 150°C heating stage to construct a parallel bypass network. Next, patterned in-plane thermal conductive paste B was printed onto the back of the heat-generating chip and the non-transparent area using screen printing technology, and then baked and dried at 130°C to form a thermally conductive layer with a heat dissipation network pattern.

[0067] The high-refractive-index resin liquid, medium-refractive-index resin liquid, and low-refractive-index resin liquid contained in the multi-stage optical encapsulation composition B are sequentially drop-coated and cured to complete the step-by-step coating of the encapsulation resin layer, and finally obtain the mobile phone display back panel integrating perovskite solar cells.

[0068] Example 3: This embodiment provides a method for fabricating a mobile phone display backplane integrating a perovskite solar cell, including the following steps: Polydimethylsiloxane and curing agent were mixed uniformly at a mass ratio of 10:1 and spin-coated onto the surface of a glass substrate at 2500 r / min. A temporary adhesive layer was prepared by annealing at 110℃ for 50 minutes. A flexible polyimide film was then bonded to the temporary adhesive layer, and interfacial bubbles were removed under vacuum. Subsequently, the surface of the flexible polyimide film was cleaned sequentially with deionized water and isopropanol, followed by UV ozone treatment for 12 minutes. The treated flexible polyimide film was then placed in a magnetron sputtering apparatus and subjected to a vacuum degree below 9 × 10⁻⁶. -4Under Pa conditions, a NiOx hole transport layer was sputtered in a preset photovoltaic region of a polyimide flexible film at a power of 60W.

[0069] A photosensitive hydrophobic barrier material C is uniformly coated on the surface of the NiOx hole transport layer. The photosensitive hydrophobic barrier material C is exposed and developed under ultraviolet light using a preset grid mask. After curing, a photosensitive hydrophobic barrier is formed distributed on the surface of the NiOx hole transport layer.

[0070] Ternary perovskite precursor solution C was injected into the spraying equipment. The gap between the nozzle and the polyimide flexible film was set to 1.2 cm, the solution injection speed to 0.30 mm / min, and the atomization pressure to 0.18 MPa. The ternary perovskite precursor solution C was sprayed onto the grid defined by the photosensitive hydrophobic isolation wall. Immediately after spraying, the wetted polyimide flexible film was transferred to the vacuum chamber. The vacuum was reduced to below 12 Pa within 12 seconds and maintained for 2.5 minutes. Subsequently, it was annealed at 155°C for 8 minutes to form a black phase ternary perovskite light-absorbing layer.

[0071] A flexible polyimide film with a black-phase ternary perovskite light-absorbing layer was placed in a vacuum evaporation chamber at a vacuum level below 9 × 10⁻⁶. -4 Under Pa conditions, a 300 Å thick C60 electron transport layer was deposited sequentially at a rate of 0.12 Å / s, followed by an 80 Å thick BCP hole blocking layer at a rate of 0.10 Å / s. Then, a 700 Å thick copper electrode was deposited at a rate of 2.0 Å / s. The photovoltaic region was then divided into multiple series-connected sub-cell units using a laser scribing process, thus completing the construction of the perovskite solar cell.

[0072] Copper metal lines were sputtered onto the non-photovoltaic areas of the polyimide flexible film, and diode mounting pads were reserved. Then, the display driver chip, photovoltaic power management chip, and micro-surface diode were surface-mounted and soldered on a 155°C heating stage using tin-bismuth low-temperature solder paste to build a parallel bypass network. Next, patterned in-plane thermal conductive paste C was printed onto the back of the heat-generating chip and the non-transparent area using screen printing technology, and then baked and dried at 140°C to form a thermally conductive layer with a heat dissipation network pattern.

[0073] The high-refractive-index resin liquid, medium-refractive-index resin liquid, and low-refractive-index resin liquid contained in the multi-stage optical encapsulation composition C are sequentially drop-coated and cured to complete the step-by-step coating of the encapsulation resin layer, and finally obtain the mobile phone display back panel integrating perovskite solar cells.

[0074] Example 4: This embodiment provides a method for fabricating a mobile phone display backplane integrating a perovskite solar cell, including the following steps: Polydimethylsiloxane and curing agent were mixed uniformly at a mass ratio of 10:1 and spin-coated onto the surface of a glass substrate at 1500 r / min. A temporary adhesive layer was prepared by annealing at 90°C for 70 minutes. A flexible polyimide film was then bonded to the temporary adhesive layer, and interfacial bubbles were removed under vacuum. Subsequently, the surface of the flexible polyimide film was cleaned sequentially with deionized water and isopropanol, followed by UV ozone treatment for 8 minutes. The treated flexible polyimide film was then placed in a magnetron sputtering apparatus and subjected to a vacuum degree below 9 × 10⁻⁶. -4 Under Pa conditions, a NiOx hole transport layer was sputtered in a preset photovoltaic region of a polyimide flexible film at a power of 50W.

[0075] A photosensitive hydrophobic barrier material A is uniformly coated on the surface of the NiOx hole transport layer. The photosensitive hydrophobic barrier material A is exposed to ultraviolet light and developed using a preset grid mask. After curing, a photosensitive hydrophobic barrier is formed distributed on the surface of the NiOx hole transport layer.

[0076] Ternary perovskite precursor solution A was injected into the spraying equipment. The gap between the nozzle and the polyimide flexible film was set to 0.8 cm, the solution injection speed to 0.20 mm / min, and the atomization pressure to 0.12 MPa. Ternary perovskite precursor solution A was sprayed onto the grid defined by the photosensitive hydrophobic isolation wall. Immediately after spraying, the wetted polyimide flexible film was transferred to the vacuum chamber. The vacuum was reduced to below 8 Pa within 8 seconds and maintained for 1.5 minutes. Subsequently, it was annealed at 145°C for 12 minutes to form a black phase ternary perovskite light-absorbing layer.

[0077] A flexible polyimide film with a black-phase ternary perovskite light-absorbing layer was placed in a vacuum evaporation chamber at a vacuum level below 9 × 10⁻⁶. -4 Under Pa conditions, a 200 Å thick C60 electron transport layer was deposited sequentially at a rate of 0.08 Å / s, followed by a 50 Å thick BCP hole blocking layer at a rate of 0.05 Å / s. Then, a 500 Å thick copper electrode was deposited at a rate of 1.0 Å / s. The photovoltaic region was then divided into multiple series-connected sub-cell units using a laser scribing process, thus completing the construction of the perovskite solar cell.

[0078] Copper metal lines were sputtered onto the non-photovoltaic areas of the polyimide flexible film, and diode mounting pads were reserved. Then, the display driver chip, photovoltaic power management chip, and micro-surface diode were surface-mounted and soldered using tin-bismuth low-temperature solder paste on a 145°C heating stage to construct a parallel bypass network. Next, patterned in-plane thermal conductive paste A was printed onto the back of the heat-generating chip and the non-transparent area using screen printing technology, and then baked and dried at 120°C to form a thermally conductive layer with a heat dissipation network pattern.

[0079] The high-refractive-index resin liquid, medium-refractive-index resin liquid, and low-refractive-index resin liquid contained in the multi-stage optical encapsulation composition C are sequentially drop-coated and cured to complete the step-by-step coating of the encapsulation resin layer, and finally obtain the mobile phone display back panel integrating perovskite solar cells.

[0080] Comparative Example 1: Compared with Example 1, the difference is that the photosensitive hydrophobic barrier material A containing perfluoropolyether segments was not used. Instead, a conventional commercially available polyurethane acrylate photoresist without fluorine was used to prepare the barrier. All other aspects are the same.

[0081] Comparative Example 2: Compared to Example 1, the difference is that the patterned in-plane thermal paste A containing highly horizontally oriented boron nitride is not used; instead, it is replaced in equal amounts with an isotropic commercially available spherical alumina thermal grease. All other aspects are the same.

[0082] Comparative Example 3: Compared with Example 1, the difference lies in reversing the process order. First, the display driver chip and the photovoltaic power management chip are surface-mounted and soldered using tin-bismuth low-temperature solder paste on a 145°C heating stage. Then, the ternary perovskite precursor solution is sprayed and the film is annealed at 145°C. The rest are the same.

[0083] Comparative Example 4: Compared with Example 1, the difference is that the outer surface is not coated with a multi-stage optical encapsulation composition in a stepped manner, but only a matrix resin with a single refractive index is used for uniform overall encapsulation of the same thickness, and no rutile titanium dioxide and silicon dioxide are added to the matrix resin, while the rest are the same.

[0084] Comparative Example 5: Compared with Example 1, the difference is that no physically isolated diode mounting pads were reserved when sputtering copper metal lines, and no miniature surface-mount diode bypass network was connected in parallel during the subsequent surface-mount soldering process; otherwise, they are the same.

[0085] Test Example 1: The mobile phone display backplates of the integrated perovskite solar cells prepared in Examples 1, 2 and Comparative Example 1 were placed in a shielded dark box with a temperature of 24 to 26°C and a relative humidity of 35 to 45% and left to stand for 2 hours.

[0086] A microwave probe station was used to perform high-frequency scanning of capacitance and voltage. Tungsten carbide microprobes were placed in contact with the copper electrode of the mobile phone display backplate integrated with perovskite solar cells and the pad of the display driver chip adjacent to the photosensitive hydrophobic isolation wall. An AC bias voltage of 1MHz was applied to both ends of the tungsten carbide microprobes using a semiconductor parameter analyzer, and a bidirectional DC bias voltage was superimposed. The scanning path of the DC bias voltage was set from -5V to +5V and back to -5V, with a scanning step of 0.1V. The interface capacitance values ​​during the bidirectional scanning process were recorded, and the hysteresis characteristics of the bidirectional scanning process of capacitance and voltage were evaluated.

[0087] Keeping the connection position of the tungsten carbide miniature probe unchanged, the test circuit is switched to the high resistance meter to perform leakage current characteristic test. First, a DC bias voltage of 0V to 20V is applied between the metal copper electrode and the display driver chip pad, and the leakage current value and the breakdown voltage threshold data at the time of insulation breakdown are recorded. Then, a constant voltage stress of 10V is applied between the metal copper electrode and the display driver chip pad, and the test is continued for 300 seconds. The steady-state leakage current value at the end of the test is recorded.

[0088] The test results are shown in Table 1.

[0089] Table 1. Test data of interface capacitance and insulation leakage current performance of the examples and comparative examples: According to Table 1 and appendix Figure 1 and attached Figure 2 The data shows that the interface capacitance densities of Examples 1 and 2 under a 0V DC bias are 12.34 pF / cm², respectively. 2 and 14.78pF / cm 2 It is lower than the 385.62 pF / cm of Comparative Example 1. 2 The smaller hysteresis loop areas in Examples 1 and 2 during the forward and reverse voltage scanning processes indicate that the photosensitive hydrophobic barrier surface forms and maintains a Cassie-Baxter wetted state.

[0090] The low surface free energy provided by the perfluoropolyether segments tends to reduce the contact area between the polar solvent and the solid phase interface. The low dielectric constant of the air layer trapped at the interface helps to reduce the overall interfacial capacitance density and interfacial trap charge accumulation in the test area. In contrast, Comparative Example 1 did not form a Cassie-Baxter wetting state, and the liquid penetrated into the interior of the microstructure, resulting in an increase in interfacial capacitance density and a large hysteresis phenomenon in the bidirectional voltage scan.

[0091] In the insulation breakdown voltage threshold test, no breakdown was observed in Examples 1 and 2 within the 20V test range. Comparative Example 1 recorded a breakdown phenomenon when the voltage was applied to 3.15V. Under a constant 10V bias, the leakage current in Examples 1 and 2 remained stable at 10V over time. -10 The leakage current of Comparative Example 1 is above the microampere level and shows a trend of degradation over time. Introducing a photosensitive liquid-repellent barrier material containing perfluoropolyether segments helps reduce the probability of lateral spread of polar solvents, provides spatial confinement for both physical and chemical boundaries, and helps reduce the formation of corrosion paths, thereby maintaining the insulation performance between the photovoltaic area inside the back panel of the mobile phone display integrated with perovskite solar cells and the microelectronic system.

[0092] Test Example 2: The mobile phone display backplates of integrated perovskite solar cells prepared in Examples 1, 3, 2, and 3 were selected as test objects. All test objects were fixed on a test optical platform without ambient wind, and the ambient temperature was controlled at a constant 24.5 to 25.5°C.

[0093] Thermal resistance analysis of the mobile phone display backplane with integrated perovskite solar cells was performed using a transient thermal impedance spectroscopy (TIS) tester. The power test probe of the TIS tester was connected to the power supply pin of the display driver chip, and a step heating current signal with a duration of 150 seconds and a power of 2.5W was injected into the display driver chip. The voltage transient change data during the system temperature cooling period was recorded using the acquisition module of the TIS tester. The voltage transient change data was converted into cumulative thermal resistance and thermal capacity integral values ​​using the built-in function of the TIS tester. The in-plane equivalent thermal resistance and out-of-plane equivalent thermal resistance of the heat-conducting layer of the mobile phone display backplane with integrated perovskite solar cells were extracted and recorded respectively.

[0094] A system-level full-load heating temperature rise test was conducted. A continuous full-load operating voltage was applied to the display driver chip of the mobile phone display back panel with integrated perovskite solar cells, causing the display driver chip to be in a continuous heating state. A K-type thin-wire thermocouple was fixed to the surface position of the geometric center of the perovskite photovoltaic area of ​​the mobile phone display back panel with integrated perovskite solar cells using thermally conductive adhesive. A multi-channel temperature recorder was started to continuously record the temperature value of the center of the perovskite photovoltaic area within 600 seconds at a sampling frequency of 1Hz. The steady-state temperature value of the perovskite photovoltaic layer at steady-state equilibrium was obtained and recorded.

[0095] The physical connection strength of the chip on the back panel of a mobile phone display integrated with a perovskite solar cell was evaluated using a microelectronic push-pull force tester. The flexible polyimide film substrate of the mobile phone display back panel with integrated perovskite solar cell was fixed, and the wedge-shaped test head of the microelectronic push-pull force tester was aligned with the bottom end of the side wall of the display driver chip. The horizontal movement speed of the wedge-shaped test head was set to 50 μm / s, and a push force was applied in the horizontal direction parallel to the flexible polyimide film until the display driver chip separated from the pad. The microelectronic push-pull force test system simultaneously recorded the push force value and the movement displacement of the wedge-shaped test head, and extracted the chip shear fracture force value corresponding to the highest peak value of the push force.

[0096] The test results are shown in Table 2.

[0097] Table 2. Test data of thermal resistance, photovoltaic layer temperature and microelectronic connection strength of the examples and comparative examples: According to Table 2 and appendix Figure 3 and attached Figure 4 The data shows that the in-plane equivalent thermal resistances of Examples 1 and 3 are 3.24 K / W and 2.87 K / W, respectively, which are significantly lower than the 14.53 K / W of Comparative Example 2. The out-of-plane equivalent thermal resistances of Examples 1 and 3 are 18.67 K / W and 19.42 K / W, respectively, which are higher than the 4.86 K / W of Comparative Example 2. This data distribution of low in-plane thermal resistance and high out-of-plane thermal resistance indicates that the patterned thermal conductive layer composed of two-dimensional hexagonal boron nitride provides a lateral phonon conduction path and blocks longitudinal heat flow.

[0098] Comparative Example 2 uses isotropic thermally conductive silicone grease and does not form a thermal blocking layer. The steady-state temperature data of the photovoltaic layer in Table 2 further reflects the influence of physical phenomena. In Comparative Example 2, the heat directly reaches the perovskite layer, causing the steady-state temperature to climb to 78.43℃. In contrast, Examples 1 and 3 control the steady-state temperature of the perovskite photovoltaic layer at 42.15℃ and 40.82℃ respectively during the full-load operation of the heat source. The difference in test data verifies that the anisotropic thermally conductive design helps to achieve thermal decoupling at the system level and reduces the efficiency of heat transfer from the underlying microelectronic components to the photovoltaic thin film layer.

[0099] Furthermore, the data in Table 2 shows that the chip shear fracture forces of Examples 1 and 3 are 24.36N and 26.11N, respectively, while the chip shear fracture force of Comparative Example 3 is only 3.42N. The low chip shear fracture force of Comparative Example 3 indicates that the mechanical properties of the microelectronic connection parts have degraded. Since Comparative Example 3 has the tin-bismuth low-temperature solder paste soldering process placed in advance, the subsequent annealing process of the perovskite light-absorbing layer above 145°C exceeds the melting point of the tin-bismuth low-temperature solder paste.

[0100] Excessive thermal budgets can lead to secondary melting of the established metal interconnect interfaces and the accumulation of micropores in the welds. The reverse ordering strategy adopted in this embodiment, which involves first preparing a high-temperature photovoltaic thin film and then performing low-temperature bonding, protects the microelectronic components from direct damage by the high-temperature heat source during photovoltaic thin film processing. This helps maintain the mechanical stability of the heterogeneous device interconnect nodes on the back panel of the mobile phone display integrated with perovskite solar cells.

[0101] Test Example 3: The mobile phone display backplates of the integrated perovskite solar cells prepared in Examples 1, 4 and Comparative Example 4 were selected as test objects.

[0102] Optical performance was tested using an ultraviolet-visible-near-infrared spectrometer with an integrating sphere attachment. The back panel of a mobile phone display with integrated perovskite solar cells was fixed to the integrating sphere test port. The incident angle of the spectrometer's probe light source was adjusted using a precision rotating stage, so that the beam was incident laterally from the outer packaging area. The spectral scanning wavelength range was set to 400 nm to 800 nm. The full-structure reflectivity and absorptivity data at different discrete incident angles from 0° to 85° were recorded and extracted. The average integrated absorptivity value in the visible light band at each incident angle was calculated. In particular, the average integrated reflectivity and average integrated absorptivity values ​​at an incident angle of 75° were extracted and recorded.

[0103] The mobile phone display back panel with integrated perovskite solar cells was transferred to a completely light-shielded electrical shielded dark room for low-light power generation performance evaluation. Low-illuminance LED light source was used to simulate the light leakage environment on the side of the display screen. The position of the low-illuminance LED light source was adjusted so that the test light with an illuminance of 500 lux irradiated the side of the outer packaging area of ​​the mobile phone display back panel with integrated perovskite solar cells at a grazing angle of 75°.

[0104] The source measurement unit is connected to the photovoltaic electrode power supply terminal of the mobile phone display back panel with integrated perovskite solar cells. A voltage scan from -0.5V to 8.0V is performed with a scan step of 10mV. The current and voltage values ​​in the output circuit are recorded. The output power in the full voltage scan range is calculated using the current and voltage values. The short-circuit current density and maximum output power values ​​during the test are extracted.

[0105] The test results are shown in Table 3.

[0106] Table 3. Test data on optical response and weak light power generation performance of the examples and comparative examples: According to Table 3 and appendix Figure 5 and attached Figure 6The data shows that, under an incident angle of 75°, the average integrated reflectance of Examples 1 and 4 is 12.83% and 11.26%, respectively, and the average integrated absorptivity is 82.47% and 84.91%, respectively. The average integrated reflectance of Comparative Example 4 is as high as 67.52%, and the average integrated absorptivity is only 16.38%. The difference in optical data suggests that the gradient refractive index distribution constructed inside the multilayer encapsulating resin satisfies the condition of total internal reflection. The encapsulating resin layer with gradient refractive index forms an asymmetric optical waveguide medium, which guides and confines the large-angle lateral stray light from the external environment to the bottom photosensitive area. Comparative Example 4 uses a single refractive index encapsulating resin, which fails to establish a gradient internal reflection boundary, resulting in the grazing beam directly penetrating or escaping along the surface.

[0107] In the low-light power generation test under a 500 lux lateral light leakage environment, Table 3 shows that the short-circuit current densities of Examples 1 and 4 are 45.16 μA / cm², respectively. 2 and 47.53 μA / cm 2 The maximum output power reached 21.94μW and 23.82μW respectively; the short-circuit current density of Comparative Example 4 was only 4.12μA / cm. 2 The maximum output power drops to 1.37 μW. The improvement in electrical output indicates that the asymmetric waveguide structure converts the optical potential energy trapped in space into physical output power.

[0108] The diffusely reflected light beam received at the edge of the mobile phone display back panel with integrated perovskite solar cells undergoes path reconstruction through the refractive index gradient within the resin encapsulation layer, reaches the active layer, and participates in the photoelectric excitation process of charge carriers. The gradient waveguide design reduces the absolute dependence of the mobile phone display back panel with integrated perovskite solar cells on the forward direct light source, which helps to improve the energy recovery and utilization rate of microelectronic mobile terminals in edge light leakage and low ambient light scenarios.

[0109] Test Example 4: The mobile phone display backplates of the integrated perovskite solar cells prepared in Examples 1, 2 and 5 were selected as test objects.

[0110] Bypass network conduction mechanism tests were conducted under no-light conditions. The mobile phone display back panel with integrated perovskite solar cells was placed in a dark room with complete electromagnetic and optical shielding. A precision source measurement unit was connected to the power management interface of the mobile phone display back panel with integrated perovskite solar cells. A reverse bias voltage scan from 0V to -5.0V was applied to the photovoltaic array, with the scan step set to 0.1V. The source measurement unit simultaneously recorded the dark current values ​​at each discrete voltage point during the reverse bias voltage scan. The bypass network conduction threshold voltage when the dark current grows exponentially was extracted, and the absolute value of the reverse dark current under the -3.0V reverse bias condition was recorded.

[0111] Global power robustness and hotspot temperature rise tests were conducted under illumination conditions. The mobile phone display backplane with integrated perovskite solar cells was placed under an AM1.5G standard solar simulator with a constant irradiance of 1000 W / m². 2 The ambient temperature was controlled at 24.5 to 25.5°C. A single sub-cell cell at the geometric center of the photovoltaic area of ​​the mobile phone display back panel with integrated perovskite solar cells was completely covered with opaque black polyimide film tape to simulate conventional physical shading.

[0112] Before and after the shading operation, a maximum power point tracking test system was connected to record the global output power data of the mobile phone display back panel with integrated perovskite solar cells within 600 seconds at discrete time intervals. A K-type thin-wire thermocouple was attached to the center of the back of the shaded sub-cell, and the temperature values ​​at each time point within the 600-second test cycle were recorded synchronously using a multi-channel temperature recorder. The steady-state global output power retention rate at 600 seconds of the test record was extracted, which is the percentage value of the shading steady-state power to the initial full-load power before shading, and the corresponding shading steady-state hot spot temperature value was obtained.

[0113] The test results are shown in Table 4.

[0114] Table 4. Test data on hot spot resistance and power robustness of the examples and comparative examples: According to Table 4 and appendix Figure 7 The data shows that in the dark-state reverse bias test, the bypass network conduction threshold voltages of Examples 1 and 2 are -0.68V and -0.62V, respectively, and the absolute values ​​of the reverse dark current under a reverse bias of -3.0V reach 45.32mA and 48.15mA, respectively. The bypass network conduction threshold voltage of Comparative Example 5 is not conducting, and the absolute value of the reverse dark current under a reverse bias of -3.0V is only 0.08mA. The difference in electrical characteristics indicates that the surface-mount bypass network integrated in the examples undergoes physical forward conduction when the photovoltaic unit is subjected to reverse bias. The bypass structure forms a low-impedance current discharge branch to guide and shunt the reverse-loaded electrical energy. Comparative Example 5 lacks a bypass network, and the photovoltaic unit exhibits a high-impedance breakdown precursor state.

[0115] In the partial shading test, Table 4 shows that the steady-state global output power retention rates of Examples 1 and 2 were maintained at 89.2% and 87.5%, respectively, and the steady-state hot spot temperature under shading was suppressed to 34.6℃ and 35.1℃. In Comparative Example 5, the steady-state global output power retention rate dropped to 21.6%, and the steady-state hot spot temperature under shading climbed to 94.3℃. The contrast in the test data indicates that when a single sub-cell cell of a mobile phone display back panel with integrated perovskite solar cells loses its photocurrent generation capability due to physical shading, the reverse bias voltage forcibly applied by the series circuit activates the bypass structure.

[0116] The current generated by the unshaded sub-units passes through the shaded area via the bypass network, avoiding the conversion of electrical energy into destructive heat energy in the high-impedance shaded area. The bypass current discharge mechanism maintains the connectivity of the global series branches, reducing the probability of local thermal damage to the mobile phone display back panel with integrated perovskite solar cells in complex grip scenarios, and helps to improve the power robustness of the photovoltaic power supply system of microelectronic mobile terminals.

[0117] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations can be made to the equipment structure, process flow, step sequence, operating parameters, or working medium type in these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the core technical solutions disclosed above and their equivalent substitutions.

Claims

1. A mobile phone display back panel integrating perovskite solar cells, characterized in that, The manufacturing process of the mobile phone display back panel includes the following steps: Polydimethylsiloxane and curing agent are spin-coated onto a carrier plate and annealed to form a temporary adhesive layer. The layer is then bonded to a flexible film substrate and interface bubbles are removed. The flexible film substrate is cleaned and treated with ultraviolet ozone. A hole transport layer is sputtered into a preset photovoltaic area. A photosensitive hydrophobic barrier material is coated onto the hole transport layer, and then exposed and cured to form a photosensitive hydrophobic barrier. The ternary perovskite precursor solution was sprayed into the grid defined by the photosensitive hydrophobic isolation wall, and then vacuumed and annealed to form a black phase ternary perovskite light-absorbing layer. An electron transport layer, a hole blocking layer, and a metal electrode are sequentially deposited on the black phase ternary perovskite light-absorbing layer, and multiple series-connected sub-cell units are divided using a laser scribing process. Metal lines are sputtered in non-photovoltaic areas, and low-temperature solder paste is used to complete the surface mounting of display driver chips, photovoltaic power management chips and micro-surface diodes; patterned in-plane thermal conductive paste is printed onto the back of the heat-generating chip and the non-transparent area and baked into a thermal conductive layer. High-refractive-index resin liquid, medium-refractive-index resin liquid, and low-refractive-index resin liquid are sequentially drop-coated and cured on the outer surface of the metal electrode and the preset photovoltaic area to complete the stepped coating and obtain the mobile phone display back panel of the integrated perovskite solar cell.

2. The mobile phone display back panel with integrated perovskite solar cells according to claim 1, characterized in that, The parameters for preparing the temporary adhesive layer and the hole transport layer are as follows: polydimethylsiloxane and curing agent are mixed evenly, spin-coated onto the carrier plate at a speed of 1500 to 2500 r / min, and annealed at 90 to 110°C for 50 to 70 minutes to form the temporary adhesive layer. The flexible thin film substrate is subjected to ultraviolet ozone treatment for 8 to 12 minutes; under a vacuum degree lower than 9 × 10⁻⁶. -4 The hole transport layer is fabricated by sputtering NiOx material at a power of 50 to 60 W under Pa conditions.

3. The mobile phone display back panel with integrated perovskite solar cells according to claim 1, characterized in that, The parameters for spraying the ternary perovskite precursor solution are as follows: the gap between the nozzle of the spraying equipment and the flexible film substrate is set to 0.8 to 1.2 cm, the solution injection speed is 0.20 to 0.30 mm / min, and the atomization pressure is 0.12 to 0.18 MPa.

4. The mobile phone display back panel with integrated perovskite solar cells according to claim 1, characterized in that, The vacuuming parameters are as follows: within 8 to 12 seconds after spraying, the vacuum level is reduced to below 8 to 12 Pa and maintained for 1.5 to 2.5 minutes.

5. The mobile phone display back panel with integrated perovskite solar cells according to claim 1, characterized in that, The annealing parameters for forming the black phase ternary perovskite light-absorbing layer are: annealing temperature controlled at 145 to 155°C, and annealing time of 8 to 12 minutes.

6. The mobile phone display back panel with integrated perovskite solar cells according to claim 1, characterized in that, The parameters for the electron transport layer and hole blocking layer deposited by vapor deposition are as follows: at a vacuum level below 9 × 10⁻⁶ -4 Under Pa conditions, a C60 material with a thickness of 200 to 300 Å is deposited at a rate of 0.08 to 0.12 Å / s as the electron transport layer, followed by a BCP material with a thickness of 50 to 80 Å being deposited at a rate of 0.05 to 0.10 Å / s as the hole blocking layer.

7. The mobile phone display back panel with integrated perovskite solar cells according to claim 1, characterized in that, The parameters for vapor deposition of the metal electrode are as follows: a copper electrode with a thickness of 500 to 700 Å is vapor deposited at a rate of 1.0 to 2.0 Å / s.

8. The mobile phone display back panel with integrated perovskite solar cells according to claim 1, characterized in that, The low-temperature solder paste is a tin-bismuth low-temperature solder paste, and the environment for completing the surface mount soldering using the low-temperature solder paste is a heating table at 145 to 155°C.

9. The mobile phone display back panel with integrated perovskite solar cells according to claim 1, characterized in that, The parameters for forming the heat-conducting layer are: baking and drying at 120 to 140°C.

10. The application of a mobile phone display backplane with an integrated perovskite solar cell as described in any one of claims 1 to 9 in the fabrication of a smartphone electronic terminal.

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