A method for preparing a patterned anisotropic conductive film based on laser hybrid manufacturing

Abstract

The application belongs to the technical field of conductive film preparation, and discloses a patterning anisotropic conductive film preparation method based on laser composite manufacturing, which comprises the following steps: step S1, performing low surface energy treatment on the surface of a substrate; step S2, performing selective scanning on the surface of the substrate after the low surface energy treatment; step S3, dispersing conductive particles in a liquid and guiding the liquid to move on the surface of the substrate; step S4, covering a first transfer film on the conductive particle layer; step S5, arranging a thickness limiting piece on the surface of the first transfer film with the conductive particles anchored; step S6, performing curing treatment on the overall structure; and heating the cured overall structure to remove the first transfer film and the second transfer film, so as to obtain the patterning anisotropic conductive film. The application realizes the position control of the conductive particles by laser control of high surface energy positions; since the conductive particles are separated from each other, the short circuit problem is avoided, and the surface of the conductive particles does not need to be insulated, so that the manufacturing process is simplified.

Description

Technical Field

[0001] This invention belongs to the field of conductive film preparation technology, specifically a method for preparing patterned anisotropic conductive films based on laser composite manufacturing. Background Technology

[0002] The rapid development of microelectronics technology has driven the continuous evolution of electronic components towards miniaturization and micro-miniaturization, placing higher demands on the connection technology between electronic components and substrates. Traditional solder bonding processes are no longer suitable for the miniaturized and narrow-pitch connection requirements, while anisotropic conductive films (ACFs), as a new type of electronic packaging material, have emerged as a leader due to their significant advantages in manufacturing processes, cost, and application range. Their core characteristics are vertical conductivity and horizontal insulation, which can precisely match the core requirements of narrow-pitch electronic connections. Existing ACFs are mainly composed of randomly distributed conductive particles, prepared by uniformly mixing conductive particles with adhesives through mechanical stirring, ultrasonic dispersion, etc., and then coating them. However, the conductive particles tend to aggregate, resulting in poor distribution uniformity and a high risk of horizontal short circuits. Therefore, the surface of the conductive particles needs to be insulated, further increasing the process difficulty. To solve the problem of conductive particle arrangement, existing technologies have proposed methods for particle screening and arrangement using molds with multiple openings.

[0003] For example, Chinese Patent Publication No. CN111205788A discloses a method for manufacturing an anisotropic conductive film. This method involves supplying conductive particles to a component with multiple openings, retaining the particles within the openings, and transferring them to an adhesive film, while controlling the particle size distribution. Another Chinese Patent Publication No. CN111205788A discloses an anisotropic film by mixing particles with an adhesive and filling the mixture into a mold with a raised or recessed pattern, creating a particle group formed by bonding multiple particles together and arranging the particle group in a regular pattern. However, both methods rely on physical molds or sieves to directly constrain and transfer the conductive particles. The dimensional accuracy and consistency of the mold openings significantly affect the arrangement effect. Furthermore, these methods struggle to achieve independent position control of individual conductive particles, and the flow of the adhesive during hot-pressing curing can still cause particle displacement, affecting product consistency and reliability. In addition, both methods require pre-screening of the conductive particles or pre-mixing with the adhesive, resulting in complex processes and insufficient flexibility. Therefore, how to achieve precise, individual patterned arrangement of micron-sized conductive particles without the direct constraint of molds, and how to solve the particle displacement problem during hot pressing, remains a technical challenge that urgently needs to be addressed in this field. Summary of the Invention

[0004] This invention aims to solve at least one of the technical problems existing in the prior art; Therefore, this invention proposes a method for preparing patterned anisotropic conductive films based on laser composite manufacturing, comprising the following steps: Step S1: Perform a low surface energy treatment on the substrate surface to make it hydrophobic overall, with a water contact angle greater than 120°; Step S2: Using a laser beam, selectively scan the surface of the substrate after the low surface energy treatment according to the preset conductive particle patterned arrangement position coordinates, so that the scanned area changes from hydrophobic to hydrophilic, and forms micro-pits in the scanned area to limit individual conductive particles. Step S3: Disperse conductive particles in a liquid and guide the liquid to move on the substrate surface. Utilize the wettability difference between the scanned area and the unscanned area to selectively retain and position the conductive particles in the micro-pits of the hydrophilic scanned area, forming a patterned conductive particle layer. Step S4: Cover the patterned conductive particle layer with the first transfer film, use the adhesion of the first transfer film to transfer the conductive particles from the substrate to the surface of the first transfer film, and then remove the substrate after anchoring the position of the conductive particles. Step S5: A thickness limiting member is provided around the conductive particle arrangement area on the surface of the first transfer film anchored with conductive particles, and an adhesive is applied; then the second transfer film is covered on the upper surface of the adhesive, and pressure is applied to clamp and fix the first transfer film and the second transfer film to form an adhesive layer. Step S6: The clamped and fixed overall structure is cured at a first temperature, which is the curing temperature of the adhesive; then the cured overall structure is heated to a second temperature to reduce the adhesion between the first transfer film and the second transfer film, which is the unadhesion temperature of the first transfer film and the second transfer film; then the first transfer film and the second transfer film are removed to obtain the patterned anisotropic conductive film.

[0005] Furthermore, in step S1, the low surface energy treatment of the substrate surface includes: introducing active groups on the substrate surface by oxygen plasma etching, and then forming a hydrophobic coating on the substrate surface by vapor deposition or spraying a hydrophobic reagent. The hydrophobic reagent is 1H,1H,2H,2H-perfluorooctyltriethoxysilane; the vapor deposition conditions are: under vacuum, heated to 110℃ to volatilize into vapor, and reacted for 2-3 hours.

[0006] Furthermore, in step S2, the laser beam is a femtosecond laser; the laser scanning parameters are configured to partially or completely remove the hydrophobic coating of the scanned area to expose the intrinsic hydrophilic surface of the substrate, while simultaneously etching micropits.

[0007] Furthermore, the micro-pits formed in step S2 have a diameter configured to be 1.2-1.5 times the diameter of the conductive particles and a depth configured to be 1.25 times the diameter of the conductive particles, in order to achieve the confinement and filling of a single conductive particle.

[0008] Furthermore, in step S3, the liquid is deionized water; the deionized water with adsorbed conductive particles is guided by a guide plate to move as a whole on the substrate surface.

[0009] Furthermore, both the first transfer membrane and the second transfer membrane are double-sided pyrolysis membranes.

[0010] Furthermore, in step S5, the thickness of the thickness limiting member is equal to the diameter of the conductive particles, and the thickness limiting member is a polyimide film.

[0011] Furthermore, in step S5, after applying the adhesive, a vacuum degassing process is performed to remove air bubbles from the adhesive and allow it to spontaneously level.

[0012] Furthermore, the substrate is an intrinsically hydrophilic ceramic substrate or metal substrate; the conductive particles are one of tin balls, gold particles, nickel particles, copper particles, silver particles or core-shell structured composite conductive particles; and the adhesive is one of polydimethylsiloxane, epoxy resin or acrylate resin.

[0013] The present invention also proposes a patterned anisotropic conductive film, which is prepared by the method described above.

[0014] Compared with the prior art, the beneficial effects of the present invention are: This invention proposes a laser-based composite manufacturing method for patterned anisotropic conductive films. This method achieves precise patterning of micron-sized particles without the need for external force fields such as magnetic or electric fields. The position of the conductive particles is controlled by laser-mediated manipulation of high surface energy. Because the conductive particles are separated, short circuits are avoided, and the surface insulation of the conductive particles is eliminated, simplifying the manufacturing process and preventing short circuits caused by subsequent peeling and breakage of the insulating material. The required number of conductive particles can be adjusted according to the size and position of the circuit board electrodes, reducing the amount of precious metals used and saving costs. The adhesive properties of the pyrolytic film anchor the conductive particles, solving the problem of particle displacement caused by adhesive flow during hot-pressing curing. Furthermore, the non-adhesive properties after pyrolysis prevent the problem of difficulty in separation after curing. Attached Figure Description

[0015] Figure 1 This is a schematic diagram showing the change in water contact angle before and after surface treatment of the substrate in this invention; Figure 2 This is a graph showing the change in surface element content after laser scanning treatment of the substrate surface according to the present invention; wherein: Figure 2 In part (a), the laser-scanned area does not display pixels of a specific color, indicating that the area does not contain the target element; Figure 2 In part (b), electron microscopy images confirm that the fluorosilane deposit in the area has been completely removed by laser. Figure 3 This is a schematic diagram of the shape of the deep micro-pits formed after laser scanning processing of the substrate surface according to the present invention; wherein: Figure 3 Part (a) shows an electron microscope image and a magnified view of the shape of the micro-pits at the depth of the un-laser-scanned processing. Figure 3 Part (b) represents the three-dimensional shape measured by confocal microscopy; Figure 3 Part (c) represents the results of width and depth measurements of the micro-pit shape at the depth of the machining process; Figure 4 This is a schematic diagram illustrating how the present invention guides deionized water to move on the surface of the substrate through a guide plate. Figure 5 This is a schematic diagram of the patterned arrangement of individual conductive particles in this invention; Figure 6 This is a schematic diagram illustrating the steps of fabricating an ACF using patterned conductive particles according to the present invention; wherein: Figure 6 Part (a) is represented as the arraying of conductive particles by liquid water guided by differences in substrate wettability. Figure 6 Part (b) represents the bonding of a pyrolytic film attached to the glass surface to an array substrate, wherein the pyrolytic film with an adhesive surface can adhere conductive particles to its surface. Figure 6 Part (c) represents the separation of the substrate from the pyrolysis film after the particles adhere to the surface of the pyrolysis film; Figure 6 Part (d) is represented by adding a PI film around the structure to form a closed rectangle, and placing the adhesive inside the rectangular area; Figure 6 Part (e) indicates that the overall structure is placed in a vacuum environment, which removes air bubbles inside the adhesive and allows the adhesive to self-level. Figure 6 Part (f) represents the bonding of the pyrolytic film to the glass on the upper surface of the leveling adhesive and the clamping under the action of the clamp. The entire structure is placed in the curing temperature for 4 hours. Figure 6 Part (g) indicates that after curing, the entire structure is placed in an environment with a pyrolysis temperature to perform pyrolysis of the pyrolysis film. Figure 6 The (h) part indicates that after cooling, the pyrolytic film is separated from the adhesive; Figure 6 Part (i) is shown as a schematic diagram of the fabricated anisotropic conductive film; Figure 7 This is a schematic diagram illustrating the patterned conductive particles of the present invention being fixed under the adhesion of a pyrolytic film and then easily peeled off without adhesion after pyrolysis; wherein: Figure 7 Part (a) indicates that before the pyrolysis of the pyrolysis film, the conductive particles are adhered to the pyrolysis film, and the flow of the adhesive does not cause the conductive particles to move. Figure 7 Part (b) indicates that the surface of the pyrolytic film loses its adhesiveness after pyrolysis, and the cured adhesive can be easily peeled off. Figure 8 The diagram shows a patterned anisotropic conductive film prepared according to the present invention, along with an electron microscope image and a magnified partial image of the anisotropic conductive film; wherein: Figure 8 Part (a) represents an anisotropic conductive film produced by the method of the present invention; Figure 8 Part (b) represents the conductivity characteristics of an anisotropic conductive film, that is, it is not conductive in the horizontal direction of the film, but conductive in the vertical direction. Figure 8 Part (c) shows an electron microscope image and a magnified view of the anisotropic conductive film, which shows that the surface of the conductive particles is exposed to the cured adhesive, giving them vertical conductivity, while the lack of direct contact between adjacent conductive particles results in no horizontal current conduction. Figure 9 This is a schematic diagram of the patterned anisotropic conductive film of the present invention used for vertical conduction in flexible circuits. Detailed Implementation

[0016] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. 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.

[0017] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that the embodiments described below are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0018] Example Reference Figures 1-9 In this embodiment, a method for preparing a patterned anisotropic conductive film based on laser composite manufacturing is provided, the specific implementation of which is as follows: (I) Preparation of experimental components and materials In this embodiment, the experimental components and materials used include: laser processing equipment and XY scanning galvanometer system, deionized water, fluorosilane hydrophobic reagent, ceramic conductive particle arrangement substrate, hydrophilic glass scraper, solder microparticles (conductive particles), PDMS prepolymer, PDMS curing agent, first transfer film and second transfer film (both of which are double-sided pyrolysis films in this embodiment), vacuum degassing box, and constant temperature oven.

[0019] It is worth mentioning that the laser processing equipment used in this embodiment generates a laser with a center wavelength of 1030nm, a pulse width of 290fs, a laser repetition frequency of 5kHz, and a maximum output power of 2W, which has advantages such as low thermal effect and high processing precision. The galvanometer system can precisely focus the output energy onto the pre-processing area and control the laser scanning trajectory. Furthermore, different laser parameters can be used depending on the substrate material and the size of the conductive particles. For example, to prevent the micro-pits from deforming due to high temperatures during processing of copper substrates, a femtosecond laser with a center wavelength of 800nm, a pulse width of 35fs, a laser repetition frequency of 1kHz, and a maximum output power of 1W can be used. The shorter pulse width results in a smaller thermal effect during processing, thus enabling the processing of undeformed micro-pits.

[0020] (ii) Substrate cleaning and low surface energy modification First, the surface of the ceramic substrate used for conductive particle arrangement is cleaned to obtain a clean arrangement substrate. For example... Figure 1 As shown, the intrinsic water contact angle of the substrate surface after cleaning is approximately 19 degrees, exhibiting hydrophilic properties.

[0021] Furthermore, the dried substrate is placed in a plasma treatment instrument, where oxygen plasma etching introduces a large number of hydroxyl (-OH) active groups onto the substrate surface. Then, under vacuum, fluorosilane reagent vapor deposition is performed on the cleaned and dried substrate surface. Specifically, a measured amount of 1H,1H,2H,2H-perfluorooctyltriethoxysilane is heated to 110°C and volatilized into vapor within the vapor deposition chamber, reacting for 2-3 hours to form a hydrophobic coating on the substrate surface.

[0022] After the above-mentioned low surface energy modification, the intrinsic hydrophilicity of the substrate surface is transformed into hydrophobicity. The contact angle of the water droplet is measured using a contact angle meter, and the contact angle is approximately 143 degrees, and it must be ensured that the contact angle is greater than 120°. Figure 1 The changes in water contact angle before and after surface treatment of the substrate arrangement are shown.

[0023] (III) Laser selective scanning and micropit formation The substrate with the low surface energy treatment described above is placed on a three-dimensional moving platform under an XY scanning galvanometer and adjusted to the processing position and laser focal point. Laser parameters are set as follows: average power 1.5W, center wavelength 1030nm, pulse width 290fs, laser repetition frequency 5kHz, and scanning speed 50mm / s. Using the XY scanning galvanometer, the laser focal spot scans the designated area of ​​the substrate.

[0024] In this embodiment, the scanned area is approximately 200 μm × 200 μm, and the scanned area is arranged in an array. Laser scanning can effectively remove the hydrophobic coating on the surface of the substrate after the low surface energy treatment, break surface carbon-fluorine bonds, and reduce fluorine content (e.g., ...). Figure 2 As shown in the figure, the intrinsic hydrophilic properties of the substrate surface are restored. Measurements showed that the water contact angle in the laser-scanned area was 46.5 degrees. This demonstrates the difference in wettability between the overall hydrophobicity of the substrate surface and the superhydrophilicity of the scanned area after the low surface energy treatment.

[0025] It should be noted that the elements such as fluorine, silicon, oxygen, and carbon contained in the fluorosilane on the substrate surface are present throughout the entire substrate surface before the femtosecond laser scan. Therefore, the elements represented by specific pixel colors can be detected across the entire substrate surface. The indicator of this detection is the uniform distribution of specific color pixels in the elemental content analysis chart.

[0026] After scanning with a femtosecond laser, the fluorosilane deposition layer on the substrate surface is removed, resulting in very low or absent levels of elements such as fluorine, silicon, oxygen, and carbon in the scanned area. The changes in elemental content are indicated by the following: if the scanned area does not contain these elements, it will appear as a black area in the elemental content analysis graph; colored areas indicate the presence of the element, while colorless black areas indicate its absence.

[0027] Therefore, through analysis Figure 2 The presence or absence of specific color pixels in part (a) (to determine whether an element exists) and their spatial distribution characteristics (to determine whether the element is relatively rich or missing in the plane) can effectively reflect the changing trend of the element content in the corresponding region.

[0028] It is worth mentioning that the area scanned by the laser will form micro-pits with a depth approximately 1.25 times the diameter of the conductive particles. For example... Figure 3 As shown, the scanning diameter of the micropit is configured to be 1.2-1.5 times the diameter of the conductive particle, and the depth of the micropit is approximately 1.25 times the diameter of the conductive particle, which is used for subsequent confinement of individual conductive particles.

[0029] (iv) Selective arrangement and patterning of conductive particles Conductive particles (tin ball microparticles in this embodiment) with a diameter of approximately 150 μm are randomly distributed on the surface of the laser-scanned substrate. Then, deionized water is poured onto the transfer substrate, where it adsorbs the conductive particles to form aggregates. Simultaneously, a glass guide plate guides the movement of the deionized water and conductive particles across the substrate surface.

[0030] It should be noted that, because the surface of the substrate after the low surface energy treatment is hydrophobic, the contact area between deionized water and the substrate surface is small, resulting in low adhesion. Therefore, it can flow controllably on the surface of the substrate after the low surface energy treatment (e.g., Figure 4 As shown, water is guided to move on the surface of the substrate by a guide plate, regulating the scattered conductive particles into a regularly distributed array. The adhesion of the hydrophilic region causes some conductive particles to remain in the hydrophilic region, while the physical confinement of the micro-pits binds one conductive particle, ensuring that each micro-pit is filled with exactly one conductive particle. Conductive particles in the hydrophobic region are adsorbed and carried away by the interfacial adsorption energy at the water-air interface, and do not remain in the hydrophobic region. Therefore, the deep micro-pit design of this invention can achieve a particle arrangement and filling rate close to 100%, forming an array as shown in the diagram. Figure 5 The patterned arrangement of single particles is shown.

[0031] (v) Transfer and anchoring of conductive particles A first transfer film (in this embodiment, a double-sided pyrolytic film) is attached to a smooth glass surface. The pyrolysis temperature of the double-sided pyrolytic film is 90°C. Then, as follows... Figure 6 As shown in part (b), a glass substrate with a double-sided pyrolytic film is attached to the surface of the substrate with the patterned arrangement of the aforementioned single conductive particles. Subsequently, as... Figure 6 As shown in section (c), the entire structure is rotated 90° so that the glass is at the bottom and the substrate is at the top. Conductive particles fall onto the surface of the double-sided pyrolysis film under gravity, and then the substrate is removed. At this point, the conductive particles are anchored to the surface of the first transfer film.

[0032] (vi) Adhesive filling and thickness control After removing the upper substrate, as shown Figure 6 As shown in section (d), a PI film with a thickness approximately equal to the diameter of the conductive particles (about 150 μm in this embodiment) is attached around the area where the conductive particles are patterned, forming a closed rectangular region. This PI film is the "thickness limiting element". Figure 6 As shown in section (e), the adhesive is poured into the closed rectangular area.

[0033] In this embodiment, PDMS is used as the adhesive. The specific preparation method is as follows: Weigh the PDMS prepolymer and curing agent into a clean beaker at a ratio of 10:1, and stir with an electric stirrer at 300-500 rpm for 5-10 minutes to ensure uniform mixing. After pouring the PDMS adhesive into a closed rectangular area, place the entire assembly in a vacuum chamber and evacuate for 20 minutes to remove air bubbles. The specific vacuum level is generally in the range of 1 kPa to 2 kPa; for PDMS vacuuming, a commonly used laboratory vacuum level is around 1.3 kPa. This vacuuming step simultaneously achieves degassing and promotes the self-leveling of the adhesive. It is worth mentioning that a vacuum environment can accelerate the self-leveling of the adhesive, resulting in a uniform thickness of the manufactured anisotropic conductive film.

[0034] In addition, such as Figure 7 As shown in part (a), the conductive particles are anchored to the surface of the pyrolysis film due to the adhesion effect. Therefore, when the adhesive is poured in, the conductive particles on the surface will not be moved, resulting in poor dispersion, thus effectively solving the problem of conductive particle displacement.

[0035] (vii) Covering and clamping the second layer of pyrolysis film Another glass slide, also with a double-sided pyrolytic film adhered to its surface, is placed on the aforementioned vacuum-sealed adhesive surface and clamped under pressure. Specifically, a commercially available spiral clamping mechanism can be used for clamping. This other double-sided pyrolytic film constitutes the second transfer film. This forms a film as follows: Figure 6 The sample shown in part (f) consists of a glass layer with a double-sided pyrolytic film on the top and bottom, and an adhesive layer with conductive particles in the center.

[0036] (viii) Curing, heating, debonding and peeling The prepared sample was cured at the first curing temperature (75°C in this embodiment) for 4 hours. Figure 6 As shown in section (g), after curing, the temperature is further increased to a second temperature (90°C in this embodiment, i.e., the debonding temperature of the pyrolysis film). This second temperature is higher than the first temperature, causing a sharp decrease in the adhesive strength of the pyrolysis film. It should be noted that, as... Figure 7 As shown in part (b), at the debonding temperature, the liquid inside the microspheres of low-boiling-point hydrocarbons encased in the thermoplastic shell of the double-sided pyrolytic film vaporizes and expands, breaking the continuity of the adhesive layer, drastically reducing the contact area and decreasing the adhesive strength. After cooling, it can be easily peeled off without residue. After removing the glass and the pyrolytic film, the following is obtained: Figure 8 The patterned anisotropic conductive film shown in part (a).

[0037] It is worth mentioning that, because the adhesive film thickness is controlled by using a PI film, the conductive particles are not completely encapsulated within the film. In specific experiments, the optimal effect is achieved when the PI film thickness and the diameter of the conductive particles are equal. Figure 8 Part (c) and its enlarged view are shown. For example... Figure 8 As shown in part (b), the conductive particles have insulating properties in the horizontal direction because they have no physical contact, while the exposure of the conductive particles allows them to conduct electricity in the vertical direction, thus producing anisotropic conductivity.

[0038] (ix) Application Validation The anisotropic conductive film fabricated above is bonded to the flexible circuit and then joined under thermo-pressing. By connecting it to an LED, it can achieve conductivity only in the vertical direction, such as... Figure 9 As shown.

[0039] It should be noted that, based on the above embodiments, the present invention can also employ various alternative solutions, as long as they do not deviate from the inventive concept of the present invention. Specifically: 1. Replaceability of substrate materials The above embodiments use a ceramic substrate, but the substrate can be selected according to specific application requirements, or it can be a metal substrate or other intrinsically hydrophilic materials, all of which are applicable to the conductive particle patterning self-arrangement method of the present invention.

[0040] 2. Replaceability of low surface energy modification methods The above embodiments achieve hydrophobic treatment of the substrate through fluorosilane vapor deposition. This method is not the only treatment approach; other surface energy modification methods can be used to achieve low surface energy, such as surface spraying with silica hydrophobic reagents, which can also achieve low surface energy modification.

[0041] 3. Replaceability of laser systems and parameters The above embodiments use a femtosecond laser with a center wavelength of 1030 nm, a pulse width of 290 fs, and a repetition frequency of 5 kHz for processing. Without changing the process objective, laser systems with other parameter combinations can also be used, such as a femtosecond laser source with a center wavelength of 800 nm, a pulse width of 30 fs, and a repetition frequency of 1 kHz, which can also achieve localized removal of hydrophobic coatings.

[0042] 4. Substitutability of conductive particles The above embodiments use tin ball microparticles, but the conductive particles can be replaced with gold particles, nickel particles, copper particles, silver particles or core-shell structure composite conductive particles (such as polystyrene core-plated gold / nickel) as needed.

[0043] 5. Adhesive replaceability The above embodiments use PDMS adhesive, but it can be replaced with resin adhesives such as epoxy resin or acrylate resin, or photosensitive polymer materials, as needed.

[0044] The embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for preparing patterned anisotropic conductive films based on laser composite manufacturing, characterized in that, Includes the following steps: Step S1: Perform a low surface energy treatment on the substrate surface to make it hydrophobic overall, with a water contact angle greater than 120°; Step S2: Using a laser beam, selectively scan the surface of the substrate after the low surface energy treatment according to the preset conductive particle patterned arrangement position coordinates, so that the scanned area changes from hydrophobic to hydrophilic, and forms micro-pits in the scanned area to limit individual conductive particles. Step S3: Disperse conductive particles in a liquid and guide the liquid to move on the substrate surface. Utilize the wettability difference between the scanned area and the unscanned area to selectively retain and position the conductive particles in the micro-pits of the hydrophilic scanned area, forming a patterned conductive particle layer. Step S4: Cover the patterned conductive particle layer with the first transfer film, use the adhesion of the first transfer film to transfer the conductive particles from the substrate to the surface of the first transfer film, and then remove the substrate after anchoring the position of the conductive particles. Step S5: A thickness limiting member is provided around the conductive particle arrangement area on the surface of the first transfer film anchored with conductive particles, and an adhesive is applied; then the second transfer film is covered on the upper surface of the adhesive, and pressure is applied to clamp and fix the first transfer film and the second transfer film to form an adhesive layer; Step S6: The clamped and fixed overall structure is cured at a first temperature, which is the curing temperature of the adhesive; then the cured overall structure is heated to a second temperature to reduce the adhesion between the first transfer film and the second transfer film, which is the unadhesion temperature of the first transfer film and the second transfer film; then the first transfer film and the second transfer film are removed to obtain the patterned anisotropic conductive film.

2. The method according to claim 1, characterized in that, In step S1, the low surface energy treatment of the substrate surface includes: introducing active groups on the substrate surface by oxygen plasma etching, and then forming a hydrophobic coating on the substrate surface by vapor deposition or spraying a hydrophobic reagent. The hydrophobic reagent is 1H,1H,2H,2H-perfluorooctyltriethoxysilane; the vapor deposition conditions are: under vacuum, heated to 110°C to volatilize into vapor, and reacted for 2-3 hours.

3. The method according to claim 2, characterized in that, In step S2, the laser beam is a femtosecond laser; the laser scanning parameters are configured to partially or completely remove the hydrophobic coating of the scanned area to expose the intrinsic hydrophilic surface of the substrate, and simultaneously etch the micropits.

4. The method according to claim 1, characterized in that, The micro-pits formed in step S2 have a diameter configured to be 1.2-1.5 times the diameter of the conductive particles and a depth configured to be 1.25 times the diameter of the conductive particles, so as to achieve the confinement and filling of a single conductive particle.

5. The method according to claim 4, characterized in that, In step S3, the liquid is deionized water; the deionized water with adsorbed conductive particles is guided by a guide plate to move as a whole on the substrate surface.

6. The method according to claim 1, characterized in that, Both the first transfer membrane and the second transfer membrane are double-sided pyrolysis membranes.

7. The method according to claim 1, characterized in that, In step S5, the thickness of the thickness limiting member is equal to the diameter of the conductive particles, and the thickness limiting member is a polyimide film.

8. The method according to claim 1, characterized in that, In step S5, after applying the adhesive, a vacuum degassing process is performed to remove air bubbles from the adhesive and allow it to spontaneously level.

9. The method according to claim 1, characterized in that, The substrate is an intrinsically hydrophilic ceramic substrate or metal substrate; the conductive particles are one of tin balls, gold particles, nickel particles, copper particles, silver particles, or core-shell structured composite conductive particles; the adhesive is one of polydimethylsiloxane, epoxy resin, or acrylate resin.

10. A patterned anisotropic conductive film, characterized in that, It is prepared by any one of claims 1 to 9.

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